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The annular ligament provides a compliant connection of the stapes to the oval window. To estimate the stiffness characteristics of the annular ligament, human temporal bone measurements were conducted. A force was applied sequentially at several points on the stapes footplate leading to different patterns of displacement with different amounts of translational and rotational components. The spatial displacement of the stapes footplate was measured using a laser vibrometer. The experiments were performed on several stapes with dissected chain and the force was increased stepwise, resulting in load-deflection curves for each force application point. The annular ligament exhibited a progressive stiffening characteristic in combination with an inhomogeneous stiffness distribution. When a centric force, orientated in the lateral direction, was applied to the stapes footplate, the stapes head moved laterally and in the posterior-inferior direction. Based on the load-deflection curves, a mechanical model of the annular ligament was derived. The mathematical representation of the compliance of the annular ligament results in a stiffness matrix with a nonlinear dependence on stapes displacement. This description of the nonlinear stiffness allows simulations of the sound transfer behavior of the middle ear for different preloads.
Techniques and biomaterials for reconstructive middle ear surgery are under steady, ongoing development. At the same time, clinical post-surgery results are evaluated to determine success or failure of the therapy. Routine quality assessment and assurance is of growing importance in the medical field, and therefore also in middle ear surgery. The exact definition and acquisition of outcome parameters is essential for both a comprehensive and detailed quality assurance. These parameters are not the audiological results alone, but also additional individual parameters which influence the postoperative outcome after tympanoplasty. Selection of patients and the preoperative clinical situation, the extent of the ossicular chain destruction, the chosen reconstruction technique and material, the audiometric frequency selection and the observational interval are only some of them. If these parameters are not well documented comparative analyses between different studies are of limited value. The present overview aims to describe, compare and evaluate some of the existing assessment and scoring systems for middle ear surgery. Additionally, new methods for an intraoperative quality assessment in ossiculoplasty and the postoperative evaluation of suboptimal hearing results with imaging techniques are available. In the area of implant development functional elements were integrated in prostheses to enable not only good sound transmission but also compensation of occurring atmospheric pressure changes. In combination with other components for ossicular repair they can be used in a modular manner which, so far show experimentally and clinically promising results.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,200
Sarcoidosis is a multisystem granulomatous disease of unknown cause. It may have several diverse manifestations that may be progressive yet develop slowly. Ocular disease may occur with inactive systemic disease. We describe two patients in whom optic nerve involvement was the first manifestation of sarcoidosis and clinically mimicked an optic nerve tumour. Sarcoidosis involving the optic nerve should be considered when an optic nerve tumour is suspected.
PURPOSE ::: To identify and characterize the MR findings of sarcoidosis when it involves the orbit and visual pathways. ::: ::: ::: METHODS ::: The MR scans of 15 patients, 3 with presumed and 12 with proved orbital or optic pathway sarcoidosis were retrospectively reviewed. ::: ::: ::: RESULTS ::: Eight patients had MR evidence of optic nerve involvement by sarcoid granuloma. Perineural enhancement was seen in four cases, optic atrophy in one. Three who had had unenhanced scans showed optic nerve enlargement. Nine patients had optic chiasmal involvement. One patient had increased T2 signal in the optic radiations. Three patients had orbital masses that had MR signal characteristics similar to pseudotumor. Five patients had periventricular white matter abnormalities closely resembling multiple sclerosis. ::: ::: ::: CONCLUSIONS ::: Sarcoidosis should be considered in the differential diagnosis of optic nerve or nerve sheath enhancement on MR. Orbital sarcoidosis has MR characteristics very similar to pseudotumor.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,201
Two distinct masses in the left orbit were incidentally found in a 48-year-old woman during a computed tomographic scan done to evaluate neurologic complaints. Initial diagnostic considerations focused on a lymphoproliferative disorder or other systemic disease. Orbitotomy revealed two discrete tumors, both cavernous hemangiomas. Although uncommon, cavernous hemangioma should be considered in the differential diagnosis of the patient with multiple orbital lesions.
Purpose: To report late recurrence of orbital cavernous hemangioma in a patient ten years after complete resection of the primary tumor. Case Report: A 32-year-old woman with a history of progressive visual loss and proptosis underwent lateral orbitotomy for resection of a large cavernous hemangioma. Ten years later, proptosis recurred and the patient developed progressive ocular deviation. Imaging studies were in favor of a recurrent cavernous hemangioma and the tumor was excised via the previous incision site. Reassessment of previous orbital images suggested the presence of two separate tumors, only one of which had been excised at the time of initial surgery. Conclusion: Recurrent orbital cavernous hemangioma may follow incomplete excision of multiple orbital lesions with gradual growth of unidentified residual tumors. Accordingly, when an encapsulated cavernous hemangioma is removed, exploration is recommended to rule out multiple lesions.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,202
Clinical investigation of female pelvic floor dysfunction has advanced significantly in recent decades. Although a careful and thorough physical examination performed to detect all defects remains paramount, even experienced clinicians can sometimes be misled by the findings. 27 A wide range of imaging modalities can confirm clinical suspicions, narrow a differential diagnosis, or reveal unsuspected defects that may influence the surgical approach. 4,14,31 This article briefly reviews pelvic floor anatomy from a radiologic perspective and discusses the clinical applications, strengths, and limitations of various imaging techniques.
The purpose of this study was to measure the internal and external anal sphincters using translabial ultrasound (TLU) at the proximal, mid, and distal levels of the anal sphincter complex. The human review committee approval was obtained and all women gave written informed consent. Sixty women presenting for gynecologic ultrasound for symptoms other than pelvic organ prolapse or urinary or anal incontinence underwent TLU. Thirty-six (60%) were asymptomatic and intact, 13 symptomatic and intact, and 11 disrupted. Anterior-posterior diameters of the internal anal sphincter at all levels and the external anal sphincter at the distal level were measured in four quadrants. Mean sphincter measurements are given for symptomatic and asymptomatic intact women and are comparable to previously reported endoanal MRI and ultrasound measurements.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,203
Tetrology of Fallot (TOF) is the most commonly encountered congenital cardiac lesion in pregnancy. Although there are controversies regarding safe anesthetic technique for parturient with TOF, we use low-dose sequential combined-spinal epidural anesthesia in such a case posted for Cesarean section and found that low dose (0.5 ml of 0.5%) intrathecal bupivacaine and fentanyl with sequential epidural bupivacaine supplementation was adequate for the performance of an uncomplicated Cesarean section with minimal side effects and good fetal outcome. Thus, though the choice of anesthesia can vary in such patients, low-dose sequential combined-spinal epidural can be a safe alternate to achieve good anesthesia with impressive cardiovascular stability.
Epidural volume extension is a technical modification of the combined spinal epidural block. It involves the epidural injection of normal saline or a small volume of local anaesthetic after an intrathecal injection, aiming to augment the post-spinal sensory level. Although the consequent sensory block augmentation has been adequately documented, the probable factors influencing epidural volume extension and its implications for clinical practice are not well defined. This article reviews published literature relating to the probable factors affecting epidural volume extension, its clinical implications, case reports of its successful clinical application and summarises its unexplored effects.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,204
Pooling specimens, a well-accepted sampling strategy in biomedical research, can be applied to reduce the cost of studying biomarkers. Even if the cost of a single assay is not a major restriction in evaluating biomarkers, pooling can be a powerful design that increases the efficiency of estimation based on data that is censored due to an instrument's lower limit of detection (LLOD). However, there are situations when the pooling design strongly aggravates the detection limit problem. To combine the benefits of pooled assays and individual assays, hybrid designs that involve taking a sample of both pooled and individual specimens have been proposed. We examine the efficiency of these hybrid designs in estimating parameters of two systems subject to a LLOD: (1) normally distributed biomarker with normally distributed measurement error and pooling error; (2) Gamma distributed biomarker with double exponentially distributed measurement error and pooling error. Three-assay design and two-assay design with replicates are applied to estimate the measurement and pooling error. The Maximum likelihood method is used to estimate the parameters. We found that the simple one-pool design, where all assays but one are random individuals and a single pooled assay includes the remaining specimens, under plausible conditions, is very efficient and can be recommended for practical use.
A storm of favorable or critical publications regarding p-values-based procedures has been observed in both the theoretical and applied literature. We focus on valid definitions of p-values in the scenarios when composite null models are in effect. A valid p-value (VpV) statistic can be used to make a prefixed level-decision. In this context, Kolmogorov Smirnov goodness-of-fit tests and the normal two sample problem are considered. In particular, we examine an issue regarding the goodness-of-fit testability based on a single observation. This article exemplifies constructions of new test procedures, advocating practical reasons to implement VpV-based mechanisms. The VpV framework induces an extension of the conventional expected p-value (EPV) tool for measuring the performance of a test. Associating the EPV concept with the receiver operating characteristic (ROC) curve methodology, a well-established biostatistical approach, we propose a Youden index based optimality principle to derive critical values of decision making procedures. In these terms, the significance level alpha=0.05 can be suggested, in many situations. In light of an ROC curve analysis, we introduce partial EPVs to characterize properties of tests including their unbiasedness. We also provide the intrinsic relationship between the Bayes Factor (BF) test statistic and the BF of test statistics. ::: Keywords: AUC; Bayes Factor; Expected p-value; Kolmogorov Smirnov tests; Likelihood ratio; Nuisance parameters; P-value; ROC curve; Pooled data; Single observation; Type I error rate; Youden index
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,205
This article considers the relevant international law pertaining to territorial sea baselines and reviews the application of that law to ice-covered coasts. The international literature concerning the status of ice in international law is examined and state practice for both the Arctic and Antarctic is reviewed. The Law of the Sea Convention contains virtually no provisions pertaining to ice, as during its negotiation, in an effort to reach a consensus, all discussion of Antarctica was avoided. International lawyers appear to favour the notion that where ice persists for many years and is fixed to land or at least is connected to ice that is connected to land, it may be able to generate territorial sea baselines. Neither the International Court of Justice nor any other international tribunal has had the opportunity to consider the status of ice, except in the most general terms. This article considers some alternatives and difficulties in their application. The impact of the Antarctic Treaty on any system...
The Antarctic has a unique political and physical architecture which is going to be difficult to reconcile with the guidelines and obligations contained within the LOS Convention. This is particularly so in relation to the LOS Convention's rules regarding the delimitation of a baseline from which both the EEZ and continental shelf are measured because of the presence of ice obscuring the true coastline. Of the seven states claiming sovereignty over Antarctic territory, Australia is one which has formally declared an EEZ off its Australian Antarctic Territory. However it has done so without first deciding where its coastal baseline will be positioned. Notwithstanding the possible political ramifications of Australia's pre- emptive declaration, there are choices available for baseline positioning which are not necessarily contained within the LOS Convention but, if treated in the usual consensual manner of Antarctic Treaty Party negotiations and the general rules of international law, represent a possible solution to this dilemma.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,206
Polycystic ovary syndrome (PCOS) increases the risk of depression, poor quality of life, and low sexual satisfaction of women. The aim of the study was to evaluate the prevalence of these disorders and to assess the need for psychological consultation at the time of PCOS diagnosis. A case-control single-center study of 250 women who were diagnosed with PCOS voluntarily filled in an anonymous, interactive questionnaire. The inquiry form included 27 questions covering the woman's characteristics, satisfaction with their outer appearance and sexual life, as well as the Beck Depression Inventory (BDI). Based on the BDI, 52% (130/250) of studied women presented depressive symptoms. This group had significantly higher body mass index (29.5 ± 8.1 vs. 24.6 ± 5.8; p<.001) and a lower level of self-attractiveness than other studied women (3.3 ± 2.2 vs. 5.4 ± 2.3; p<.001). Forty two percent (106/250) of women viewed themselves as unattractive. A correlation between reduced sexual satisfaction and a sense of low attractiveness was noted (r = 0.465, p<.001). Sixty four percent (160/250) of women believed that psychological consultation should be offered to all PCOS women. Treatment of PCOS women should be multidisciplinary and include psychological counseling, especially in obese PCOS women with inadequate family support and dissatisfied with their sexual life.
Introduction ::: Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting 5–10% of women of reproductive age. It is characterized by chronic anovulation leading to menstrual disorders, and increased infertility. The syndrome can also manifest as hirsutism and acne.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,207
This article re-examines the dating of two Psalms of lamentat (74 and 79) in the light of the Exile. The author's work on the Psalms of Asaph (76, 77 and 78) convinced him that these psalms result from the events which occurred around 721 B.C. (the fall of the Northern Kingdom) and around 701 B.C. (the Assyrian attack on Jerusalem), especially because the Asaph Psalms not only appear to have been compiled but also show a strong group identity. This re-examination shows that Psalm 74, just like Psalms 76-78, which were studied previously, dates from the time of the Assyrian hegemony and that this Psalm laments the destruction of the sanctuaries in the Northern Kingdom (especially at Bethel). On the other hand the exilic origin of Psalm 79 is to be maintained. The author of Psalm 79 was acquainted with Psalm 74, which had been re-interpreted in the Exile, and was likewise in contact with the Asaph guild, namely with those who were responsible for the exilic composition of their psalm group.
The reference to mythical traditions in Psalm 74 is not just an allusion to a common set of motifs. It is an essential strategy to gain hope in desperate times, when the country is completely destroyed. The article shows this mainly by working on the structure and the metaphors of the psalm. The authors of Psalm 74 created hope in a hopeless situation by referring to a dimension beyond the visible sphere. The deeds of YHWH/Elohim in the mythical traditions cannot be reached by the enemies: the God-established orders of time and space cannot be destroyed by their violence.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,208
“J. Edgar Hoover was like a sewer that collected dirt. I now believe he was the worst public servant in our history” (Summers, 193). These words, obviously holding nothing back, were spoken by Attorney General Laurence Silberman, the first person to go through Hoover’s secret files after his sudden death in 1972. Considering that things had started out so well for J. Edgar Hoover—born on January 1st, he was 1895’s “Baby New Year” and was later voted 1930’s “Bachelor of the Year,” two quite notable if strikingly incongruent honors—how did it all go so wrong? How did he wind up being compared to a “sewer that collected dirt,” and what circumstances led to his being called “a martinet, a preposterous figure” (Robins, 353) by poet Theodore Roethke in a 1963 issue of Harper’s Bazaar?
The war on terrorism weakened the distinction between observing suspicious bodies and torturing them. This article examines ‘enhanced interrogation’ (or torture) practices developed after 9/11 and considers that techniques used overseas by the United States may be applied domestically. The role of the FBI is highlighted since it now has assumed the central authority to interrogate all terrorist suspects held by the United States. Although enhanced interrogation no longer is permitted, the conservative perspective still views it as legitimate conduct and ignores the victimization of innocent people misidentified as terrorists.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,209
1. The Secular Moral Concept of Evil 2. Evil Action 3. Evil, Extremity, and Incomprehensibility 4. Thick and Thin Accounts of Evil Action 5. Assessing Thick and Thin Accounts 6. Conceptual Pluralism about Evil Action 7. Aggregative Accounts of Evil Personhood 8. Dispositional Accounts of Evil Personhood 9. Evil Feelings 10. Evil and Explanation 11. Doing Away with Evil? Bibliography Index
A commonly accepted claim by philosophers investigating the nature of evil is that the evil person is, in some way, the mirror image of the moral saint. In this paper I will defend a new version of this thesis. I will argue that both the moral saint and the morally evil person are characterized by a lack of conflict between moral and non-moral concerns. However, while the saint achieves this unity through a reconciliation of the two, the evil person does so by eliminating moral concerns from her character.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,210
Contents Foreword / Mario Vargas Llosa Acknowledgments Introduction / Efrain Kristal Los heraldos negros --The Black Heralds Plafones agiles -- Agile Soffits Buzos -- Divers De la tierra -- Of the Earth Nostalgias imperiales -- Imperial Nostalgias Truenos -- Thunderclaps Canciones de hogar -- Songs of Home Trilce Poemas humanos -- Human Poems I II Espana, aparta de mi este caliz -- Spain, Take This Cup from Me Afterword: A Translation Memoir Appendix: A Chronology of Vallejo's Life and Works / Stephen M. Hart Notes Bibliography Index of Spanish Titles and First Lines Index of English Titles and First Lines
Considering the implicit North American and Anglophone core of Asian American literature traditionally conceived, this essay discusses two examples of literatures of the Asian Americas. A narrative of a Chinese coolie’s heroic escape from a Peruvian guano mine, Ruthanne Lum McCunn’s novel God of Luck (2008) introduces a lesser-known point of view to the field: the nineteenth-century Chinese coolie in Peru. Rather than embrace the emblematic hero who accedes to voice, this essay attempts to read outside of an anticipated rubric of individual politico-economic repletion. In the poetry of Peruvian writer Jose Watanabe (1946–2007), motifs of animal encounter abound—yet dogs, fish, and other kinds of life are never deployed as a discrete metaphor through which we can see and know ourselves. As readers we are shifted to the edge of the world, in a “becoming-animal” that explores not the Asian American, but its restless morphing, illegibly human or otherwise.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
kor_Hang
24,211
The protracted struggle of Fedor Glinka (1786-1880) to publish his poetic imitation of the Book of Job (1859) reveals some of the tensions inherent in the relationship between literature, church and state during a period of critical change. Glinka was inspired by the desire of Protestant theologians such as Herder to refashion the Bible in a new, post-Enlightenment spirit. In Russia, where literary adaptations of the Bible were a highly contested site, he encountered strong opposition. At the heart of this battle lies the question of who could lay claim to the authority defined by ‘ownership’ of the sacred word – the poet, the ecclesiastical censor, the civil censor, or the tsar?
The Russian image of the artist as a prophet is generally regarded as a verbal construct, developed through literary tradition. The paper introduces a new perspective: the role of the visual arts. Focusing on the relationship between Aleksandr Ivanov (1806-58) and Nikolai Gogol' (1809-52), it argues that Ivanov's visual treatment of prophecy (in 'The Appearance of the Messiah to the People', 1833-57) interacted with and influenced Gogol's literary approach (in Dead Souls, 'The Portrait', Selected Passages from Correspondence with Friends). Tensions over the relative value of the image and the word in creating new forms of religious art and competition over assuming the role of leading prophet led to a crisis point in their relationship around 1848.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,212
Starting from Frances Tustin's description of failure of the containing function in autistic children due to a splitting between the masculine and feminine aspects of the containing object, the author suggests that the first stage in the psychoanalytic treatment of an autistic child consists in restoring that function by working through what he calls the transference on to the container. His description of container bisexuality differs slightly from that given by Tustin. In the author's description, the masculine elements of the container do not penetrate the female ones, but rather strengthen them in the same way as buttresses strengthen a building. Once the transference on to the container is sufficiently worked through, the child can begin to trust the containing capacities of the object. Thereafter, an infantile transference, as defined by Melanie Klein, begins to develop. That transference tends to have a special intensity in autistic children, with the emergence of a fantasy that Tustin called the ‘...
This paper gives a detailed account of a participative observation in a home setting. The careful observation of the interaction between the baby and the observer, the mother and the observer and the baby and his mother clearly demonstrates that there was no constitutional factor involved in the diagnosed risk of autism for this baby. This paper also proposes that the establishment of a particular quality of containing space between observe and observed, which the author identifies as a musical space, was an essential element in the recovery of this baby to ordinary development.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,213
Dynamic textures are temporally continuous and infinitely varying sequences of images with certain spatial and temporal stationarity properties and have many potential applications such as computer graphics, computer vision, animation, and computer games. These applications usually require dynamic texture segmentation that is not an easy task especially when the background is cluttered and textured. In this paper, we analyze the spatio-temporal slices of dynamic texture using Fourier analysis and then we propose a simple and efficient approach to dynamic texture segmentation using 3D Fourier transform. Experiments on several dynamic texture sequences show the effectiveness of the proposed approach.
A method for detection of dynamic textures in video is proposed. It is observed that the motion vectors of most of the dynamic textures (e.g. sea waves, swaying tree leaves and branches in the wind, etc.) exhibit random motion. On the other hand, regular motion of ordinary video objects has well-defined directions. In this paper, motion vectors of moving objects are estimated and tracked based on a minimum distance based metric. The direction of the motion vectors are then quantized to define two three-state Markov models corresponding to dynamic textures and ordinary moving objects with consistent directions. Hidden Markov models (HMMs) are used to classify the moving objects in the final step of the algorithm.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,214
This paper proposes and compares the state estimation scheme and performance of the Extended Kalman Filter and the Unscented Kalman Filter. A highly nonlinear flexible manipulator is targeted by the study to evaluate the effectiveness and robustness of the proposed filters facing an online accurate estimation problem. An Euler-Bernoulli cantilever beam models the manipulator, and the elastic movement is approximated using the assumed modes method. The Hamilton’s principle yields the system nonlinear equations. This article compares, via the included numerical simulation results, the efficiency of the state estimate reflected by the estimation error and the time required by the filters to converge.
The input–output control strategy needs all of the states feedback. However, in flexible link robot manipulators, measuring the time rate of elastic degrees of freedom is practically impossible. In this paper, a new nonlinear high gain observer has been developed to estimate the elastic degrees of freedom and their time derivatives. The control strategy is based on an output redefinition approach which stabilizes the zero dynamics of the manipulator. Finally, the results are presented by implementing the proposed observer and controller on a single link flexible manipulator. Numerical simulations will support the validity of our research results.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,215
We investigate the stability of asymptotically anti-de Sitter gravity coupled to tachyonic scalar fields with mass at or slightly above the Breitenlohner-Freedman bound. The boundary conditions in these ``designer gravity'' theories are defined in terms of an arbitrary function W. Previous work had suggested that the energy in designer gravity is bounded below if i) W has a global minimum and ii) the scalar potential admits a superpotential P. More recently, however, certain solutions were found (numerically) to violate the proposed energy bound. We resolve the discrepancy by observing that a given scalar potential can admit two possible branches of the corresponding superpotential, P_{\pm}. When there is a P_- branch, we rigorously prove a lower bound on the energy; the P_+ branch alone is not sufficient. Our numerical investigations i) confirm this picture, ii) confirm other critical aspects of the (complicated) proofs, and iii) suggest that the existence of P_- may in fact be necessary (as well as sufficient) for the energy of a designer gravity theory to be bounded below.
We address proposed alternatives to the black hole firewall. We show that embedding the interior Hilbert space of an old black hole into the Hilbert space of the early radiation is inconsistent, as is embedding the semi-classical interior of an AdS black hole into any dual CFT Hilbert space. We develop the use of large AdS black holes as a system to sharpen the firewall argument. We also reiterate arguments that unitary non-local theories can avoid firewalls only if the non-localities are suitably dramatic.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,216
C. Thomassen classified Klein-bottle polyhexes into five classes [C. Thomassen, Tilings of the torus and the Klein bottle and vertex-transitive graphs on a fixed surface, Trans. Amer. Math. Soc. 323 (1991) 605-635]. In this paper, by implementing cutting and gluing operations, we reclassify the five classes of Klein-bottle polyhexes into two classes-the bipartite case K(p,q,t) and the non-bipartite case N(p,q,t). Further, we completely characterize 2-extendable and k-resonant non-bipartite Klein-bottle polyhexes, respectively.
Fowler and Pisanski showed that the Fries number for a fullerene on surface Σ is bounded above by , and fullerenes which attain this bound are exactly the class of leapfrog fullerenes on surface Σ. We showed that the Clar number of a fullerene on surface Σ is bounded above by , where stands for the Euler characteristic of Σ. By establishing a relation between the extremal fullerenes and the extremal (4,6)-fullerenes on the sphere, Hartung characterized the fullerenes on the sphere for which Clar numbers attain . We prove that, for a (4,6)-fullerene on surface Σ, its Clar number is bounded above by and its Fries number is bounded above by , and we characterize the (4,6)-fullerenes on surface Σ attaining these two bounds in terms of perfect Clar structure. Moreover, we characterize the fullerenes on the projective plane for which Clar numbers attain in Hartung’s method.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,217
A dynamic priority discipline called head-of-the-line with priority jumps is proposed as an efficient link schedule for a packet switch serving multiple classes of delay-sensitive traffic. Implementation of this discipline is considered to be relatively simple, and the processing overhead relatively small. It is shown that, by properly adjusting the control parameters, the discipline can: (i) satisfy any relative average delay requirements for the different classes, thus bringing fairness of service, and resulting in resource saving, and (ii) make the tail probability of the delay distributions for the different classes beyond their targeted maximum delays approximately the same, thus approximately minimizing the overall maximum tail probability in the system. >
This letter suggests a modified priority scheduling policy for the asynchronous transfer mode (ATM) multiplexer, which is called DQLT. In the dual queue length threshold (DQLT) method, there exist two queues: (1) Q/sub 1/ is for nonreal-time traffic and (2) Q/sub 2/ is for real-time traffic and each queue has its own threshold to adaptively control the buffer congestion. If Q/sub 1/ is congested over the threshold T/sub 1/ one cell at the head of Q/sub 1/ moves into Q/sub 2/ in a slot time. It is shown that the DQLT method gives intermediate performance between those of minimum laxity threshold (MLT) and queue length threshold (QLT) policy, but its control method is quite simpler.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
eng_Latn
24,218
After the research and analyze of demand and capacity management in supply chain, the paper proposed an analysis model of MRP and supplier's capacity based on the demand data model and capacity data model to cover the limitations in current management of demand and capacity. Through the practical application of the model in enterprise, the results showed that the bottleneck of capacity can be found in advanced under the normal and maximal production capacity and the decision supports to adjust the production plan and capacity of suppliers were provided.
To provide customers with products on time,the Manufacturing Resource Planning(MRPⅡ)systems or Enterprise Resource Planning(ERP)systems are introduced to many manufacturers The Capacity Requirements Planning(CRP)is a basic function of MRPⅡ/ERP systems.But the CRP has some weaknesses.For example,it has no capability to adjust the processes and the work centers when they are out of work or the loads on them are out beyond their capacities,and it is on the hypothesis of infinite capacities when calculating the loads of work centers.The author of this paper presents the concept of adaptable processes set and work centers set for a single step in a material process plan after analyzing the mechanism and algorithm of CRP.A new idea including conditions such as the finite capacities of work centers,the workers and the devices for CRP is puts forward by the author.The author also presents an improved algorithm of CRP that reduces the quantity of calculation.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We investigate the capacity and mutual information of a broadband fading channel consisting of a finite number of time-varying paths. We show that the capacity of the channel in the wideband limit is the same as that of a wideband Gaussian channel with the same average received power. However, the input signals needed to achieve the capacity must be "peaky" in time or frequency. In particular, we show that if white-like signals are used instead (as is common in spread-spectrum systems), the mutual information is inversely proportional to the number of resolvable paths L/spl tilde/ with energy spread out, and in fact approaches 0 as the number of paths gets large. This is true even when the paths are assumed to be tracked perfectly at the receiver. A critical parameter L/spl tilde//sub crit/ is defined in terms of system parameters to delineate the threshold on L over which such overspreading phenomenon occurs.
We consider using DS-CDMA over channels which decorrelate in frequency. We allow the bandwidth to increase while maintaining a fixed total average power. The bandwidth over which we transmit is divided into several slices, each of which has its own spreading sequence. We show that for a large bandwidth DS-CDMA spreading is not advantageous when the channel truly decorrelates in frequency or when the channel bandwidth slices are correlated but not jointly estimated.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This paper presents an intelligent decision algorithm and an on-board architecture designed to enable an autonomous underwater vehicle (AUV) to carry out a survey mission autonomously. The connotation of global model in decision algorithm is analyzed, including environment information, mission information and Self-states of AUV. The survey mission of multi-objective operation areas in an unsafe zone including forbidden areas and obstacles is defined. Based on these, the intelligent decision algorithm including global path optimization and speed optimization is researched. Operational research method is used to optimize the path and genetic algorithm is used to optimize the speed. The on-line mission management architecture is designed to call the decision algorithm and supervise the implementation of the autonomous mission based on Petri net formalism. The feasibility and the algorithm effectiveness of the architecture and intelligent decision algorithm are checked by lake experiment in nominal and degraded situations.
Autonomous robots are complex machines embedding: software modules implementing basic functions such as servo loops to follow a path, or to compute stereo correlation of a pair of images; software to take into account the interactions between the robot components; programs which deal with the supervision and the planning of the mission. These components are integrated within an architecture which defines an organization and a methodology for robot operation.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Estimation of multivariate regression functions from i.i.d. data is considered. We construct estimates by empiricalL2-error minimization over data-dependent spaces of polynomial spline functions. For univariate regression function estimation these spaces are spline spaces with data-dependent knot sequences. In the multivariate case, we use so-called hierarchical spline spaces which are defined as linear span of tensor product B-splines with nested knot sequences. The knot sequences of the chosen B-splines depend locally on the data. We show the strongL2-consistency of the estimators without any condition on the underlying distribution. The estimators are similar to histogram regression estimators using data-dependent partitions and partitioning regression estimators based on local polynomial fits. The main difference is that the estimators considered here are smooth functions, which seems to be desirable especially in the case that the regression function to be estimated is smooth.
The paper deals with kernel estimates of Nadaraya-Watson type for a regression function with square integrable response variable. For usual bandwidth sequences and smooth nonnegative kernels, e.g., Gaussian and quartic kernels, strongL2-consistency is shown without any further condition on the underlying distribution. The proof uses a Tauberian theorem for Cesàro summability.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The theory of rotating open-channel flow between two basins is presented and experimentally verified for three cases. The first case considered is the submerged weir-flow, i.e. the height of the channel floor is below the free-surface height of the fluid in the lower basin. Flow for this case is found to depend on the fluid level in the downstream basin when the fluid level there is high and is independent of the fluid level downstream as soon as the level falls below a critical height; at that point the flow in the channel becomes critical (controlled). The dependence of the flow on upstream potential vorticity and on rotation rate is also examined. It is shown that transport of the flow decreases whenever rotation rate or upstream potential vorticity is increased. The second case studied is controlled flow through a channel of irregular cross section (the truncated channel). Transport of this flow is shown to increase at some moderate rotations if the channel floor has a cross-channel slope similar to that of the surface of the current. Otherwise, the transport always decreases with rotation rate. The final case is concerned with supercritical separation of the current downstream of the control section, i.e. the current separates from the left wall of the channel (looking downstream). Visual evidence and measurements of formation of such a boundary current are obtained. Comparisons between the theory and the experiment for the three cases are generally reasonable except when flow separates in the control section; the theory is found inapplicable to such separation.
Saddle points between neighboring deep ocean basins are the sites of unidirectional flow from one basin to the next, depending on the source of bottom water. Flow in these sites appears to be topographically controlled so the interface between the bottom water and the water above adjusts itself to permit bottom water flow from the basin that contains a source of bottom water into the next. Examples in the Atlantic include flow in the Romanche Fracture Zone, the Vema Channel, the Ceara Abyssal Plain, the Anegada-Jungfern passage, and the Discovery Gap, but there are many more. Theoretical predictions of volume flux using a method that requires only conductivity-temperature-depth data archives and detailed knowledge of bathymetry near the saddle point are compared with volume flux estimates using current meters and/or geostrophic estimates for seven cases. The ratio of prediction to volume flux estimate ranges from 1.0 to 2.7. Some ocean straits that separate adjacent seas are also found to critically control bidirectional flows between basins. Theory of the influence of rotation on such critical flows is reviewed. Predictions of volume flux in eight cases are compared with ocean estimates of volume flux from traditional methods.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The aim of this research was to enhance the physicochemical properties of potato starch (PS), tapioca starch (TS) and chitosan (CS) based bionanocomposite films by incorporating with different levels of turmeric nanofiber (TNF). The TNF was prepared from turmeric spent by acid hydrolysis accompanied with high pressure homogenization. The morphology of the bionanocomposites was analyzed by SEM and it revealed their large aggregation cluster with dense structure through tightly packed TNF in the biocomposite films. The attainment of bionanocomposites due to the formation of fresh hydrogen bonds between the hydroxyl groups of PS, TS and CS with TNF authenticated by FT-IR spectroscopy. XRD results exhibited the disappearances of peaks of TNF indicating the reinforcement of TNF in the prepared bionanocomposite matrixes. The tensile strength and Young's modulus of the bionanocomposites were improved tremendously through increasing TNF concentration due to the formation of starch-TNF and chitosan-TNF network. DSC data indicated the addition of TNF significantly increased the onset temperature, peak temperature and conclusion temperature of bionanocomposites; however, the enthalpy change values considerably decreased. The antibacterial test showed the bionanocomposites exhibited excellent antibacterial performance against Bacillus cereus, Escherichia coli, Staphylococcus aureus and Salmonella typhimurium due to the addition of TNF in the biopolymer matrixes.
The aim of study was to investigate the influence of kaolin on the physical properties and utility of film produced from native starch. The work involved measurements of strength, structure, and thermal properties. The films were prepared by the casting method. Composite films with 0%, 5%, 10%, and 15% kaolin additives were examined. Measurements of mechanical properties were carried out using the uniaxial tensile test, the nanoindentation test, and nanoscratching. Surface properties were examined by atomic force microscopy and contact angle measurements. Structure was determined by the X-ray diffraction method, and thermal properties were determined by differential scanning calorimetry. A significant influence of kaolin on the strength parameters and thermal and barrier properties of composite films was found. An increase in kaolin content reduced the tensile strength, Young’s modulus, and Poisson’s ratio. Structural analysis showed a partial intercalation and the layered arrangement of kaolin particles. Kaolin additives increased the barrier properties of water vapor in composite films of about 9%. Biopolymer modification by nanoclay reduced the thermal stability of composite films by 7% and could accelerate the biodegradation process. Increasing the concentration of kaolin in the biopolymer matrix led to heightened surface roughness (approximately 64%) and wettability of the surfaces of the film composites of 58%.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We present results of transmittance measurements on periodic layers of ZrO2/SiO2 at optical frequencies. These one- dimensional photonic band gap materials exhibit transparency bands and a huge stop band at optical frequencies. A unique feature of these dielectric/dielectric photonic band gap (MM- PBG) materials is that the overall reflectance in the stop band may increase as more periods are deposited. The center frequency and width of the stop bands are adjustable and generally depend on the thickness of the layers and the number of ZrO2/SiO2 periods. These simple periodic structures have applications as microcavity reflector in microcavity lasers.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Two class AB GaAs field-effect transistor (FET) power amplifiers have been designed and fabricated in the 4.4-4.8 GHz range. In the first case, a dielectric PBG line was incorporated in the design to tune the second harmonic. In the second case, a 50-/spl Omega/ line is used with no harmonic tuning. The PBG structure allows broad-band harmonic tuning and is inexpensive to fabricate. A 5% improvement in power-added efficiency was achieved at the design frequency of 4.5 GHz, in both simulation and measurement.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Central Europe, Moravia, and Past Paleolithic Research. Pleistocene Paleoenvironments V. Lozek. Patterns of Human Evolution E. Vlcek Lower and Middle Paleolithic Background. Origins of the Upper Paleolithic. Culmination and Decline of the Upper Paleolithic. Western Invasion. Creating Settlement Systems. Appendix A: Catalog of Important Sites. Appendix B: List of Sites. Index.
This research was funded by the German Science Foundation (DFG) (grant MO-2369/1). M.B.'s research is funded by the Austrian Academy of Sciences. PRN's research is funded by an EC FP7 Career Integration Grant (NEMO-ADAP, Grant nr. 322261), the Leakey Foundation, the University of Cambridge and the Max-Planck-Society. We would like to thank Walpurga Antl-Weiser (Department of Prehistory, Natural History Museum, Vienna) for access to the Willendorf II assemblages and assistence during the data collection. We are also indebted to Anton Kern (Department of Prehistory, Natural History Museum, Vienna) for providing working space during extended stays in Vienna and the hospitability of his team at the Department of Prehistory. Further, we would like to thank Gerhard Trnka (Department of Prehistoric and Historic Archaeology, University of Vienna) for access to his Lithothek and discussion of raw material sources.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This chapter surveys the methods available for extracting information from option prices that can be used in forecasting. We consider option-implied volatilities, skewness, kurtosis, and densities. More generally, we discuss how any forecasting object that is a twice differentiable function of the future realization of the underlying risky asset price can utilize option-implied information in a well-defined manner. Going beyond the univariate option-implied density, we also consider results on option-implied covariance, correlation and beta forecasting, as well as the use of option-implied information in cross-sectional forecasting of equity returns. We discuss how option-implied information can be adjusted for risk premia to remove biases in forecasting regressions.
We use the information in intraday data to forecast the volatility of crude oil at a horizon of 1-66days using a variety of models relying on the decomposition of realized variance in its positive or negative (semivariances) part and its continuous or discontinuous part (jumps). We show the importance of these decompositions in predictive (in-sample) regressions using a number of specifications. Nevertheless, an important empirical finding comes from an out-of-sample analysis which unambiguously shows the limited interest of considering these components. Overall, our results indicates that a simple autoregressive specification mimicking long memory and using past realized variances as predictors does not perform significantly worse than more sophisticated models which include the various components of realized variance.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In this article, a technique based on the acoustic emission (AE) signal fractal and wavelet analysis are proposed for tool condition monitoring. it is difficult to obtain an effective result by these raw acoustic emission data. The local characterize of frequency band, which contains the main energy of AE signals, is depicted by the wavelet multi-resolution analysis, fractal dimension can describe the complexity of time series. It is found that the fault signal can effectively be extracted by wavelet transform and fractal dimension. Experimental results prove that this method is effectively.
The cutting sound in the audible range includes plenty of tool wear information. The sound is sampled by the acoustic emission (AE) sensor as a short-time sequence, then worn wear can be detected by the Duffing-Holmes oscillator. A novel engineering method is proposed for determining the chaotic threshold of the Duffing-Holmes oscillator. First, a rough threshold value is calculated by local Lyapunov exponents with a step size 0.1. Second, the exact threshold value is calculated by the Duffing-Holmes system in terms of the law of the golden section. The advantage of the method is low computation cost. The feasibility for tool condition detection is demonstrated by the 27 kinds of cutting conditions with sharp tool and worn tool in turning experiments. The 54 group data sampled as noisy are embedded into the Duffing-Holmes oscillator, respectively. Finally, one chaotic threshold is determined conveniently which can distinguish between worn tool or sharp tool.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This paper presents a multi-objective optimization model to determine the optimal solutions for the problem of sizing and locating distributed generation facilities. Cost minimization is achieved through the minimization of system losses; complex power acquired from DG units and the number of connected DG units. A Simulated annealing technique is implemented to optimize the proposed multi-objective model. A typical case study is presented and the results obtained are discussed.
In this paper, a new probabilistic model using measures of classifier competence and diversity is proposed. The multiple classifier system (MCS) based on the dynamic ensemble selection scheme was constructed using both developed measures. Two different optimization problems of ensemble selection are defined and a solution based on the simulated annealing algorithm is presented. The influence of minimum value of competence and diversity in the ensemble on classification performance was investigated. The effectiveness of the proposed dynamic selection methods and the influence of both measures were tested using seven databases taken from the UCI Machine Learning Repository and the StatLib statistical dataset. Two types of ensembles were used: homogeneous or heterogeneous. The results show that the use of diversity positively affects the quality of classification. In addition, cases have been identified in which the use of this measure has the greatest impact on quality.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Transitional flow structures in the shear layer of a laminar ::: separation bubble downstream of a backward facing step ::: (BFS) have been investigated by means of 2D-2C- und highly ::: resolved 3D-3C- tomographic Particle Image Velocimetry ::: (PIV) for Reynolds numbers between Re = 1420 and 3000 ::: based on free-stream velocity U and step height h. By using an external acoustic excitation of the shear layer it was possible to arrange phase locked measurements of the wavy flow structures which emanate from instabilities according to ::: Kelvin-Helmholtz (KH). Snapshots of fully 3D-3C velocity vector volumes show complex flow topologies of the ::: non-linear part of the laminar-turbulent transition scenario. ::: This part seems to be governed by hairpin-like, streamwise ::: elongated vortices on top of the classical spanwise oriented 2- ::: D waves. These vortices organize a rapid fluid exchange ::: normal to the shear layer leading to turbulent reattachment of ::: the flow and subsequent development of a turbulent boundary ::: layer.
The flow behind a backward facing step of 6 mm in height has been investigated by means of high-resolution tomographic PIV. The shedding of vortices was stabilized by acoustic excitation, enabling phase-locked measurements of the flow field in a volume of 70x95x7 mm3. The gathered vector volumes with a vector spacing of approx. 0.25 mm in each direction were investigated by the method of conditional averaging. Basic flow structures, related to Q2 and Q4-events were extracted and their development in time was characterized, using methods of joint probability density functions of the fluctuations and of the invariants of the velocity gradient tensor.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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An analytical model is presented to predict the static behavior of the long-span prestressed concrete bridge deck(the long-span PSC deck). The finite element analysis is performed and the results are compared with that of the previous experimental test. The load-deflection relationship curves by FEM are in good agreement with the results reported in the previous study. The failure mode of all test specimens is predicted by the punching shear in this study. It is also observed in the previous experimental test. The main objective of this paper is presenting supportive method to predict static behavior of the long-span PSC deck slab. It is not simulating the punching shear behavior graphically.
This paper presents part of an investigation on the failure modes in reinforced concrete bridge decks subjected to monotonic static concentrated wheel-loads. The punching shear deck failure appears to be interrelated with a snap-through instability of an “arching” action mechanism activated in the deck. The predicted critical deflection of about 25% of the deck thickness at instability of a two-dimensional laterally restrained three-hinge compressive strut mechanism correlates well with the measured static ultimate deck deflection values of bridge decks that failed primarily in punching. There is also good agreement between the predicted critical applied static concentrated load at instability of the proposed three-hinge truss and the experimental static deck ultimate strength values.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We propose an optimization algorithm to solve the brachytherapy seed localization problem in prostate brachytherapy. Our algorithm is based on novel geometric approaches to exploit the special structure of the problem and relies on a number of key observations which help us formulate the optimization problem as a minimization integer program (IP). Our IP model precisely defines the feasibility polyhedron for this problem using a polynomial number of half-spaces; the solution to its corresponding linear program is rounded to yield an integral solution to our task of determining correspondences between seeds in multiple projection images. The algorithm is efficient in theory as well as in practice and performs well on simulation data (approximately 98% accuracy) and real X-ray images (approximately 95% accuracy). We present in detail the underlying ideas and an extensive set of performance evaluations based on our implementation.
This paper presents a hybrid approach for developing radiation plans for high dose rate brachytherapy in cancer treatment. In order to take care of the computationally hard dose volume constraints, linear programming (LP) is alternated with heuristic neighborhood search which allows for a quick generation of multiple feasible treatment plans. The simulated annealing neighborhood search is guided by both the primal and dual information available after each LP optimization. The approach is very promising compared to a traditional mixed integer programming approach for dealing with the dose volume constraints.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A monolithic microwave and digital integrated circuit (MMDIC) consisting of a 12-b serial-to-parallel converter, 6-b phase shifter, 4-b attenuator, and a single-pole double-throw (SPDT) switch has been designed and fabricated using the standard multifunction self-aligned gate (MSAG) process, with a full functional yield of over 27%. By combining digital circuitry with these microwave control circuits, the number of control lines is reduced from 16 to 3. The on-chip combination of multiple circuit functions, including both digital and microwave, not only simplifies the bonding connections, but also reduces the subsystem cost, and increases its reliability. >
In this contribution, several Multi-Functional Chips featuring different functionalities and integration levels are presented. A X-Band Core-Chip integrating a 6-bit attenuator, a 6-bit phase shifter, a T/R switch and a digital serial-to-parallel converter has been fabricated with 0.18 μm OMMIC ED02AH process. The MMIC exhibits 6 dB and 8 dB average insertion gain for transmit and receive mode respectively, full 360° phase coverage with 5.6° phase steps and 31.5 dB attenuation dynamic range with 0.5 dB amplitude resolution in less than 16 mm2. Two C-Band Multi-Functional Chips, one consisting of a bidirectional 6-bit phase shifter with on-board digital controls and the other integrating a 6-bit phase shifter, a buffer amplifier and a 5-bit attenuator have been fabricated with the 0.4 μm E/D GaAs process developed by SELEX Sistemi Integrati. The former exhibits full 360 degree phase coverage with 5.6° phase resolution in less than 18 mm2. The latter is an unidirectional MMIC featuring 8 dB average gain, full 360 degree phase coverage with 5.6° phase steps and 31 dB attenuation range with 1 dB amplitude resolution in less than 26 mm2.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A space frame model for the analysis and design of cargo containers used in marine, rail and road transportation is proposed. The analysis of the model is based on the stiffness method. Some loading conditions are simulated in accordance with International Standards Organization (ISO) requirements. The stresses and deflections obtained from the model are compared with experimental results.
This paper does some research on the mechanical property of multilayer container structure under high temperature and gives some suggestions on how to make fire protection based on the performance-based fire design. Firstly, using the software of FDS (Fire Dynamics Simulator), the fire background and fire heating release curve are determined. Through the simulation, the actual temperature curves (of the top and bottom temperature curves of the middle, door, and corner position in the container) are obtained and compared with the standard temperature curve of ISO-834. Secondly, using the software of Abaqus, a full scale finite element model of multilayer container structure is established. Two temperature fields under the standard temperature curve of ISO-834 and the actual temperature curve (of the most unfavorable curve of the top temperature curve of the middle position in the container) are obtained, respectively. Thirdly, the thermal-mechanical coupled analysis is carried out for the container structure under the wind loading and temperature field. The research result can be feasible in design and construction of container buildings and provides some references to corresponding specification preparation.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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InnoWEE is a four-year project (from 2016 to 2020) financed by the European Community that involves ten partners from different European countries, as Greece, Italy, Belgium, Romania, Slovenia, Spain and Poland. The aim is to use the waste materials coming from construction and demolition processes of buildings and include them into a geopolymeric matrix with the purpose of producing prefabricated panels for different applications. Construction and demolition waste (CDW) materials with suitable characteristics have been selected to develop high performance geopolymeric panels for building walls envelopes and radiant panels for indoor walls and ceilings with low environmental impact. Field tests will be carried out in different sites in Europe characterized by different climatic conditions to check the simplicity of the installation procedure and the performance of the panels in terms of energy efficiency and environmental impact.
Electric radiant heating panels are frequently selected during the design phase of residential and industrial heating systems, especially for retrofit of existing buildings, as an alternative to other common heating systems, such as radiators or air conditioners. The possibility of saving living and working space and the ease of installation are the main advantages of electric radiant solutions. This paper investigates the thermal performance of a typical electric radiant panel. A climatic room was equipped with temperature sensors and heat flow meters to perform a steady state experimental analysis. For the dynamic behavior, a mathematical model was created and compared to a thermographic measurement procedure. The results showed for the steady state an efficiency of energy transformation close to one, while in a transient thermal regime the time constant to reach the steady state condition was slightly faster than the typical ones of hydronic systems.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Subglacial water modulates glacier-bed friction and therefore is of ::: fundamental importance when characterising the dynamics of ice masses. The ::: state of subglacial pore water, whether liquid or frozen, is associated with ::: differences in electrical resistivity that span several orders of magnitude; ::: hence, liquid water can be inferred from electrical resistivity depth ::: profiles. Such profiles can be obtained from inversions of transient ::: (time-domain) electromagnetic (TEM) soundings, but these are often ::: non-unique. Here, we adapt an existing Bayesian transdimensional algorithm ::: (Multimodal Layered Transdimensional Inversion – MuLTI) to the inversion of TEM data using independent depth constraints ::: to provide statistical properties and uncertainty analysis of the ::: resistivity profile with depth. The method was applied to ground-based TEM ::: data acquired on the terminus of the Norwegian glacier, Midtdalsbreen, with ::: depth constraints provided by co-located ground-penetrating radar data. Our ::: inversion shows that the glacier bed is directly underlain by material of ::: resistivity 10 2 Ω m ± 1000 %, with thickness 5–40 m, in ::: turn underlain by a highly conductive basement (10 0 Ω m ± 15 %). ::: High-resistivity material, 5×104 Ω m ± 25 %, ::: exists at the front of the glacier. All uncertainties are defined by the ::: interquartile range of the posterior resistivity distribution. Combining ::: these resistivity profiles with those from co-located seismic shear-wave ::: velocity inversions to further reduce ambiguity in the hydrogeological ::: interpretation of the subsurface, we propose a new 3-D interpretation in ::: which the Midtdalsbreen subglacial material is partitioned into partially ::: frozen sediment, frozen sediment/permafrost and weathered/fractured bedrock ::: with saline water.
Satellite observations have revealed active hydrologic systems beneath Antarctic ice streams, but sources and sinks of water within these systems are uncertain. Here we use numerical simulations of ice streams to estimate the generation, flux, and budget of water beneath five ice streams on the Siple Coast. We estimate that 47% of the total hydrologic input (0.98 km3 yr−1) to Whillans (WIS), Mercer (MIS), and Kamb (KIS) ice streams comes from the ice sheet interior and that only 8% forms by local basal melting. The remaining 45% comes from a groundwater reservoir, an overlooked source in which depletion significantly exceeds recharge. Of the total input to Bindschadler (BIS) and MacAyeal (MacIS) ice streams (0.56 km3 yr−1), 72% comes from the interior, 19% from groundwater, and 9% from local melting. This contrasting hydrologic setting modulates the ice streams flow and has important implications for the search for life in subglacial lakes.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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[Context and motivation] Service Orientation has been heralded as the solution for seamless alignment of the business and IT. [Question/problem] Alignment, however, remains far from being resolved. [Principal ideas/results] While alignment research typically concentrates on mapping the counterpart elements, this paper provides a case for what we coin consonance—the mutual adjustment of conflicting requirements between business and IT perspectives. In previous work, we have identified inherent discrepancies between the requirements of the business- and IT perspectives. [Contribution] In this paper, to better understand such discrepancies and the kind of support needed for their consonance, we have carried out a real-world example in the music industry. Moreover, we study consonance in a networked setting; both in terms of a business network of enterprises, and in terms of a cross-organizational IT network. The use of the consonance approach in this example reveals important lessons learned.
This paper presents the Architecture Tradeoff Analysis Method (ATAM), a structured technique for understanding the tradeoffs inherent in the architectures of software-intensive systems. This method was developed to provide a principled way to evaluate a software architecture's fitness with respect to multiple competing quality attributes: modifiability, security, performance, availability, and so forth. These attributes interact-improving one often comes at the price of worsening one or more of the others-as is shown in the paper, and the method helps us to reason about architectural decisions that affect quality attribute interactions. The ATAM is a spiral model of design: one of postulating candidate architectures followed by analysis and risk mitigation, leading to refined architectures.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Application of a new area efficient body contact to LDMOSFET devices in silicon-on-insulator (SOI) material has been investigated using three-dimensional simulation. A comparative study of the new body contact and a conventional body-contacted structure for high voltage SOI devices is presented. Using the new body contact, current drive (IDS) was increased by 14% and current gain cut-off frequency (fT) by 10%. In addition, improved performance is achieved when comparing on-resistance (Ron) and breakdown voltage (VBR). The new body contact structure is applicable to both high-voltage planar or trench SOI and bulk devices.
Detailed experimental results are used to develop a new model for the linear region of operation of lateral DMOSFETs (LDMOSFETs) on silicon-on-insulator (SOI) that includes the influence of the buried oxide and back-gate. Back-gate biasing results in double-channel conduction and bias-dependent series resistance. Pertinent techniques for parameter extraction are presented and contrasted to those currently used in low-voltage SOI MOSFETs. The typical feature of LDMOSFETs is the significant change in series resistance as the back-gate is driven from accumulation to inversion. The model allows a clear identification of the architectural and technological parameters of the device.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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It is the duty of every employer to provide its employees with safe, hygienic and ergonomic working conditions. Available information suggests that working conditions in Poland improve each year, thanks to the ever-growing security culture prevailing in Polish enterprises. In spite of everything, there is still a problem of hazards in the workplace, and special attention should be paid to acoustic threats - vibrations and audible noise. Although entities operating on the market offering comprehensive services to reduce the exposure of employees to vibroacoustic hazards, there is still a need to develop new methods to protect the health of employees. Excessive exposure to vibrations and noise is associated with negative health effects that are exposed to, among others, employees involved in the mechanical processing of steel structures. Employees also experience the impact of local and general vibrations. Local vibrations can be relatively easily eliminated using anti-vibration gloves, while the reduction of general vibrations is often an unresolved problem for employees and employers. The publication presents the results of research on the development of the method of damping mechanical vibrations generated during grinding steel constructions. The research included several stages, among others: selection and preparation of the research material, design and construction of the test stand, measurements of vibration acceleration and industrial verification of the obtained results.
A strong issue on the development of new vehicles is the weight reduction, required for the reduction of the fuel consumption and the CO2 emissions. The current vehicles have already a structure optimised to have low weight without reducing the required performances. However, there are some components of the structure that can be further reduced in weight still matching the resistance, crash and fatigue performances, but giving a poor performance in terms of noise and vibrations and increasing both the structure-borne and air-borne sound transmission.In the European FP7 project Green City Car, flexible, integrated passive and active solutions are developed permitting noise and vibration attenuation in vehicles equipped with the next generation of highly fuel-efficient two- or three cylinder internal combustion engines (ICE). Among others, shunted piezoelectric patches and electro-magnetic actuation as well as smart Helmholtz resonators are considered. Additionally, dedicated active noise control systems for the control of broadband rolling noise are developed. Besides, Green City Car addresses and implements novel damping materials and acoustic treatments as well as design approaches for tyres which are an important acoustic source for exterior and interior noise. This holistic approach should lead to a reduction in noise and vibrations levels in the order of 10 dB(A) and more measurable in the city car provided (not on component level). Currently, Green City Car finished its second year and first results are presented and discussed in this paper
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Personal construct theory provides both a plausible theoretical foundation for knowledge acquisition and a practical approach to modeling. Yet, only a fraction of the ideas latent in this theory have been tapped. Recently, several researchers have been taking a second look at the theory, to discover new ways that it can shed light on the foundations and practice of knowledge acquisition. These efforts have led to the development of three “second-generation” constructivist knowledge acquisition systems: DDUCKS, ICONKAT, and KSSn/KRS. These tools extend repertory grid techniques in various ways and integrate them with tools springing from complementary perspectives. New understandings of relationships between personal construct theory, assimilation theory, logic, semantic networks, and decision analysis have formed the underpinnings of these systems. Theoretical progress has fostered practical development in system architecture, analysis and induction techniques, and group use of knowledge acquisition tools.
We give a preliminary perspective on the basic principles and pitfalls of adjustable autonomy and human-centered teamwork. We then summarize the interim results of our study on the problem of work practice modeling and human-agent collaboration in space applications, the development of a broad model of human-agent teamwork grounded in practice, and the integration of the Brahms, KAoS, and NOMADS agent frameworks We hope our work will benefit those who plan and participate in work activities in a wide variety of space applications, as well as those who are interested in design and execution tools for teams of robots that can function as effective assistants to humans.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The annealing of voids and vacancy dislocation loops previously found in slowly cooled crystals of NiAl (Fraser, Loretto, Smallman and Wasilewski, 1971) has been studied using transmission electron microscopy. It is observed that both types of defect grow during annealing even when it is carried out in a vacuum of about 10−7 torr and that the detailed behaviour is consistent with vacancy introduction by surface oxidation. The occurrence of voids in as-grown single crystals, and the formation of vacancy-type loops in quenched NiAl (Ball and Smallman 1968) may now be interpreted in terms of surface oxidation rather than a low energy of formation of vacancies in NiAl.
▪ We review here the theory of the early stages of oxidation of the (110) surface of Ni1−x Alx, based on ab initio calculations using a plane-wave pseudopotential method. The clean surface and several oxidized surfaces have been investigated, with oxygen coverages up to 2ML of oxygen (1ML = 3 O atoms per 2 surface Al atoms). The theory to date is a description in terms of equilibrium thermodynamics, with a comparison of the free energies of several surfaces of different composition, implemented at the atomic scale. Three environmental parameters are singled out as control variables in this treatment, namely the alloy composition x (assumed to be near 0.5), the temperature T and the partial pressure of oxygen pO2. With certain reasonable approximations an analytic formula for the surface energy σ is derived in terms of these variables and some constants that are calculated ab initio together with others that are derived from experimental thermodynamic tables. At oxygen pressures just above the thr...
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The applicability and analytical power of political ecology is improved by study of the 'ethno-ecological context', which is based on the concept of socio-ecological systems (SES). It represents an operating principle of interactions between the ecological and social systems of a specific locality, developing under different historical, political and climatic regimes. We compare two socio-ecological systems in the high mountain regions of Georgia – the Skhalta Gorge and the Upper Svaneti. These are on the southern and northern borders of Georgia. Historically, their socio-ecological systems were similar but today the Skhalta Gorge is rapidly depopulating, whilst in the Upper Svaneti the population is stable. The comparison of the ethno-ecological context and today's state of affairs suggests that (i) "self-regulation" and conserving local culture and traditions, whilst the country undergoes rapid social and political changes, can lead to degradation or even destruction of either the ecological or the social components; (ii) conversely, sustainable development results from active intervention rather than abstaining from it; (iii) tourism appears as a mechanism that restores the ethno-ecological context by providing a source of income - under certain conditions, it supports traditional agriculture. Key words: Political ecology, ethno-ecological context, socio-ecological systems, Georgia, Adjara, Svaneti, Mulakhi community, Skhalta Gorge, sustainability, tourism.
The present invention is an interferometric SAR system and processing method that combines multi-pass SAR interferometry with dual-antenna SAR interferometry to obtain elevation maps with accuracy unobtainable by either method alone. A single pass of the dual-antenna system provides coarse elevation maps. High accuracy maps are obtained through additional passes, with accuracy determined by the number of passes. The processing method combines the acquired data to provide a calibrated, high precision, low ambiguity elevation map, using approximate least-squares and maximum-likelihood processing methods. The present dual-antenna SAR interferometer collects two complex SAR images from slightly different elevation angles on a single pass using two antennas on the same platform. The present invention provides calibrated maps that have coarse precision but are nearly unambiguous because of the small interferometer baseline. The multi-pass method collects two or more complex images using multiple passes of a radar platform with each antenna. Alone, the multipass method provides much more precise, but ambiguous and uncalibrated, elevation maps. However, the present invention combines the dual-antenna and multi-pass techniques to provide unambiguous and highly precise maps.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We focus our attention on the selection processes and turn-on delay for the switch-on of different transverse modes in VCSELs. We consider different excitation conditions and active-region diameters, addressing the experimental situations in which the transient response of gain-guided VCSELs to a current pulse is taken into account (1 ns duration, 100 ps rise-time). We consider two thermal effects, namely, a temperature dependent detuning between the band-gap and the cavity resonance and the thermal lensing (TL) effect.
We study theoretically the non linear polarization dynamics of Vertical-Cavity Surface-Emitting Lasers in the presence of an external cavity providing delayed optical feedback and cross polarization re-injection. We show that far from the laser threshold, the dynamics remains confined close to the equatorial plane of a Stokes sphere of a given radius and we reduce the dynamics to a dynamical system composed of two phases: the orientation phase of the quasi-linear polarization and the optical phase of the field. We explore the complex modal structure given by the double feedback configuration and recovers as particular cases the Lang-Kobayashi modes and the modes founds by Giudici et al. [1]. We also re-interpret the square waves switching dynamics as phase kinks.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A repetitive X-band relativistic backward-wave oscillator (BWO) driven by a SINUS-881 accelerator is described. Relativistic electron beams with peak current of 5.4 kA and voltage of 610 kV at a repetition rate of 100 Hz were generated by the SINUS-881 and then guided through the corrugated waveguide by an axial magnetic field of 3.0 T produced by a superconducting magnet. An electron collector was used to collect the electron beams in order to mitigate the effect of secondary emission electrons and to prevent ionization and breakdown near the electron beam dump. This BWO produces a microwave pulse power of 1.1 GW at a 100-Hz repetition rate, a frequency of 9.38 GHz, a pulse duration of 23 ns, and a power transforming efficiency of 33%.
A high power microwave (HPM) device packaged with permanent magnet is realized experimentally based on a relativistic backward wave oscillator (RBWO). The experimental results show that the frequency of the $\textit {Ku}$ -band device is 16.15 GHz and the microwave power is 1.06 GW with an efficiency of about 25% in the case in which the diode voltage is 620 kV, the beam current is 6.9 kA, and the guiding magnetic flux density is 0.94 T. The result of continuous operation for 1 s at a repetition rate of 50 Hz indicates that the RBWO with permanent magnet can operate at a high repetition rate.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The analysis of the disinfection effect of Nd:YAG laser radiation was investigated for patients with high ::: concentration of Streptococcus mutans in saliva (positive result in Saliva-check mutans test). For the interaction the ::: Nd:YAG laser system generated separate switchable wavelengths with the maximum output energies 1.1, 0.6, and ::: 0.3 J for wavelength 1.06 μm, 1.32, μm and 1.44 μm, respectively, was used. Our study proved that after the laser ::: irradiation the Saliva-check test showed negative presence of Streptococcus mutans. The disinfection effect was ::: confirmed for all used radiation wavelength. For 1.44 μm this effect was reached with a smallest energy density.
The Nd3+:YAG laser pumped by a CW 5-kW krypton arc-lamp was tuned to 19 different transitions from 1.052 to 1.444 μm by means of intracavity thin solid etalons and appropriately coated resonator mirrors. Each transition was tunable over 6-12 wavenumbers and most exhibited 10-30-W CW output, attaining 37 W at 1.319 μm and 52 W at 1.112 μm. The 1.061-μm line is 90 percent as strong as at 1.064 μm, and wavelength shift with temperature variation was measured for both. TEM 00 output of 20 W was available by using apertures, and compensation of thermal lensing resulted in 60 W combined TEM 00 + TEM 01 output.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We propose a censored quantile regression estimator motivated by unbiased estimating equations. Under the usual conditional independence assumption of the survival time and the censoring time given the covariates, we show that the proposed estimator is consistent and asymptotically normal. We develop an efficient computational algorithm which uses existing quantile regression code. As a result, bootstrap-type inference can be efficiently implemented. We illustrate the finite-sample performance of the proposed method by simulation studies and analysis of a survival data set.
A generalized Kaplan-Meier estimator has been considered in the literature on conditional survival analysis (Beran (1981), Gonzalez-Manteiga and Cadarso-Suarez (1991) and Gentleman and Crowley (1991)). An almost sure representation as a sum of independent variables is given here for this estimator. Some applications are obtained as consequences of these results.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The International Technology Roadmap for Semiconductors [3] predicts chip complexities by the end of this decade silicon of around 1 billion transistors integrated on a single piece of silicon. It will open new frontiers in terms of applications in areas/devices ranging from security systems (e.g. video surveillance), control systems (e.g. automotive control), individual health systems (e.g. hearing aids) to main stream consumer products in such areas as personal communication (e.g. cell phones), personal computing (e.g. PDA), entertainment (e.g. MP3 players), video/photo (e.g. digital still/video cameras) and many more. It can be observed that especially the latter group of main stream consumer products is subject to severe competition between major manufacturers and thus leading to two effects from a consumer’s point of view:
Successfully applying formal methods to software development promises to move us closer to a true engineering discipline. The authors offer suggestions for overcoming the problems that have hindered the use of formal methods thus far.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The accurate prediction of laminar-turbulent transition in hypersonic boundary layers is a critical part of the aerodynamic heating analyses on hypersonic vehicles. Since 1950s, extensive wind-tunnel and flight-test experiments on boundary layer transition and a number of stability experiments have been conducted for hypersonic flows over circular cones [1, 2]. Schneider [1, 2] did an extensive review of the existing literature on these experiments for both flight test and wind tunnel experiments. Though many of these experiments did not measure transition mechanisms and were carried out in noisy wind tunnels, the experimental studies have led to better understanding of the effects on transition of many parameters, including nose bluntness, Mach number, freestream noise, surface and stagnation temperatures, freestream unit Reynolds numbers, cone half angles, angles of attack, and surface roughness, etc. Nevertheless, so far, the effects of many of these parameters on transition are still not well understood.
A highly polished 15 degree included-angle cone-cylinder with hemispherical tip has been flown to obtain boundary-layer transition and heat-transfer data. The model was launched from a carrier plane at an altitude of 47,500 feet. Laminar flow existed at a Reynolds number greater than 38.5 x 10(exp) 6 on the cylinder when the model was at the peak free-stream Mach number of 8.17. The results indicate an appreciable and favorable effect of tip bluntness in raising the allowable skin temperature for a given boundary-layer transition Reynolds number.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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VLF sprites are identified by high angle scattering of VLF transmissions by the conducting plasma columns which appear as the luminous columns of “red sprites”. VLF sprites are “early/fast Trimpis” and probably vice versa. Recently discovered properties of early/fast Trimpis are the logarithmic decay of the amplitude of the scattered signal and monotonic variation of its phase. These properties are explained in terms of scattering from a vertical column or set of columns extending from 50 km (or lower) altitude to about 80 km.
Lightning produces electromagnetic fields and waves in all frequency ranges. In the extremely low frequency (ELF) range below 100 Hz, the global Schumann Resonances (SR) are excited at frequencies of 8 Hz, 14 Hz, 20 Hz, etc. This review is aimed at the reader generally unfamiliar with the Schumann Resonances. First some historical context to SR research is given, followed by some theoretical background and examples of the extensive use of Schumann resonances in a variety of lightning-related studies in recent years, ranging from estimates of the spatial and temporal variations in global lighting activity, connections to global climate change, transient luminous events and extraterrestrial lightning. Both theoretical and experimental results of the global resonance phenomenon are presented. It is our hope that this review will increase the interest in SR among researchers previously unfamiliar with this phenomenon.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A fully on-chip CMOS relaxation oscillator (ROSC) with a PVT variation compensation circuit is proposed in this paper. The circuit is based on a conventional ROSC and has a distinctive feature in the compensation circuit that compensates for comparator's non-idealities caused by offset voltage and delay time. We also developed a bias circuit consisting of positive and negative temperature coefficient resistors to obtain the temperature compensated clock frequency. Measurement results demonstrated that the circuit can generate a stable clock frequency of 6.66 kHz. The power dissipation was 940 nW. The measured line regulation and temperature coefficient were 0.98%/V and 56ppm/°C, respectively.
In this paper, we present a novel on-chip relaxation oscillator (RO) with high temperature stability. By employing delay compensation circuit (DCC) in the delay loop, the transmission delay, which is highly sensitive to the temperature variation, is well-suppressed, leading to significantly elevated temperature stability of the RO's period. In addition, the proposed RO implementation features a low power consumption of 0.11μW at 25° C, using 65nm 1.2V standard CMOS process. Moreover, according to our extensive simulation results, the variation of our proposed RO's output frequency is reduced to ±0.18% with the working temperature ranged from −55° C to 125° C, outperforming the other state of art RO designs.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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An analysis is made of the velocity, temperature and pressure distributions in a turbulent vortex with radial and axial flow. For making the calculations the vortex is divided into a core and an annular region, each with a different uniform axial mass velocity, although the equations obtained are applicable to an arbitrary axial mass velocity distribution. Tangential velocity, temperature and pressure distributions, as well as curves for overall energy or temperature separation, are presented and compared with experiment. Using the analytical results, the causes of the energy separation are studied. It is concluded that the most important factor affecting the total temperature of a fluid element in a compressible vortex is the turbulent shear work done on or by the element.
The buoyancy-induced vorticity concentration produced as the fluid in a vortex accelerates vertically was studied. The boiloff from liquid nitrogen, to which a small amount of initial vorticity was added, provided a source of cool, heavy gas in which a concentration of vorticity took place. Condensation streamers made the flow visible. It is shown that the presence of a surface boundary layer is not necessary for the effective concentration of vorticity. A simple theoretical analysis of the phenomenon was also made. A radial contraction of the flow with vertical position and a characteristic hook shape in the top view of the streamlines were observed in both theory and experiment. The vorticity concentration observed may be similar to that which occurs in tornadoes.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Analytical expressions of AC magnetic susceptibility χ AC were given for some critical state models of superconductor, such as Rollins–Silcox, Kimishima, Bean, and Anderson–Kim models. From the AC field dependence of magnetization, the in-phase and out-of-phase linear χ AC of χ 0 ′ and χ 0 ″, and nonlinear third harmonic components of χ 2 ′ and χ 2 ″ are represented by the function of α . Here α is the (mean) penetration field normalized by the AC field amplitude H AC , and it is proportional to the (mean) critical (surface) current density. The α 3/2 -dependence of χ 0 ′ against small α was obtained for each model, except for the A–K model with the α 3 -dependence of χ 0 ′. It was found that the analytical expressions for χ 0 ″ were most simple and useful to estimate the (mean) critical (surface) current density from the experimental data, and the validity of each model should be confirmed by the behaviors of non-linear χ 2 ′ and χ 2 ″.
We have measured the critical current density ( ${J_{{C}}}$ ) of a sample of SuNAM HTS tape using ac susceptibility (ACS) and dc magnetization (DCM) techniques. In DCM measurements, inhomogeneity ( $\delta B$ ) in the applied dc field causes a systematic underestimate of ${J_{{C}}}$ . The error in DCM measurements is characterized by the penetration parameter, $\gamma = \frac{{3\pi {\chi _0}\delta B}}{{({3w - \frac{{{w^2}}}{l}}){\mu _0}{J_{{C}}}}}$ , and grows as ${J_{{C}}}$ decreases. Using a harmonic ACS analysis, we have obtained more accurate measurements of ${J_{{C}}}$ as a function of applied dc field and temperature for $\gamma \approx 1$ .
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A transparent model was developed to directly observe phenomena occurring in the slag and metal layers during electro-slag remelting. The stirring pattern observed in the slag layer is attributed to an electromagnetic effect and a theory for this is proposed. Other qualitative observations of temperature distributions, boundary layers, submerged arcing and droplet formation and fragmentation are also reported. The effect of the droplets on heat transfer and the final ingot structure are briefly discussed.
A better understanding of droplet formation and dripping behavior would be useful in the efficient removal of impurity elements and nonmetallic inclusions from liquid metals. In the present work, we developed a transparent experimental apparatus to study the mechanisms of droplet formation and the effects of filling ratio on droplet behavior during the electroslag remelting (ESR) process. A high-speed camera was used to clearly observe, at small time scales, the droplet formation and dripping phenomenon at the slag/metal interface during a stable ESR process. The results illustrate that a two-stage process for droplet formation and dripping occurs during the ESR process and that the droplet diameter exhibits a parabolic distribution with increasing filling ratio because of the different shape and thermal state of the electrode tip. This work also confirms that a relatively large filling ratio reduces electricity consumption and improves ingot quality.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We have investigated the use of an object database as a platform for storing and retrieving Standard Generalized Markup Language (SGML) documents. Qualitative studies convinced us that object databases are a perfect fit for supporting SGML document management. Unfortunately, quantitative benchmark results showed that the particular object database management system (ODBMS) product we used was not capable of supporting large scale SGML applications due to certain defects in its system architecture. The most critical defect was a weak support for location-independent persistent object identifiers. We strongly believe however, ODBMSs in general are perfect platforms and continue the experiment using another ODBMS product. We explain why and how an ODBMS fits well with SGML document management applications, describe how the benchmark experiment was performed and what were the results, and finally present a list of features as a recommendation to those interested in developing or using an ODBMS in support for SGML document management.
This paper presents a taxonomy of previous work on infrastructures, architectures and development environments for representing and processing Language Resources (LRs), corpora, and annotations. This classification is then used to derive a set of requirements for a Software Architecture for Language Engineering (SALE). The analysis shows that a SALE should address common problems and support typical activities in the development, deployment, and maintenance of LE software. The results will be used in the next phase of construction of an infrastructure for LR production, distribution, and access.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The Voigt‐Reuss‐Hill (VRH) approximation, a useful scheme by which anisotropic single‐crystal elastic constants can be converted into isotropic polycrystalline elastic moduli, is shown to apply for moderately anisotropic cubic crystals like MgO, CaF2, β‐ZnS, ZnSe, and CdTe. Experimental values of polycrystalline isotropic elastic moduli for these materials are presented here, and the validity of the VRH approximation is established. The VRH approximation is then discussed for these materials with respect to their elastic anisotropy of crystals. To provide further support to this work, a numerical confirmation on the VRH moduli is made with the use of a high‐speed computer by calculating the mean velocity of sound in crystals and comparing this result with the corresponding quantity calculated from the actual polycrystalline elastic moduli. The general agreement is observed.
The stability of cubic HfV2 ( F d 3 ¯ m ) was investigated as a function of temperature as well as interstitially solved oxygen and hydrogen using density functional theory. Mechanical and energetic instability of pristine cubic HfV2 is obtained in the ground state at 0 K, which is unexpected as it can readily be synthesized. Combined Debye–Gruneisen and electronic entropy calculations indicate that HfV2 is stabilized with increasing temperature primarily as a result of lattice vibrations. In contrast, temperature-induced mechanical stabilization, considering the Born stability criteria, is achieved due to the electronic entropy. Interstitial incorporation of hydrogen and oxygen into the cubic structure contributes to the energetic and mechanical stabilization in the ground state for impurity concentrations as low as 1 at%, owing to strong ionic/covalent bond formation with the matrix atoms.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This paper presents a method for analysing the unstable vibration of a car disc brake, and numerical results are compared with squeal frequencies from an experimental test. The stationary components of the disc brake are modelled using many thousands of solid and special finite elements, and the contacts between the stationary components and between the pads and the disc are considered. The disc is modelled as a thin plate and its modes are obtained analytically. These two parts (stationary and rotating) of the disc brake are brought together with the contact conditions at the disc/pads interface in such a way that the friction-induced vibration of the disc brake is treated as a moving load problem. Predicted unstable frequencies are seen to be close to experimental squeal frequencies. The numerical simulation indicates that the stability can be improved by shifting the centre of the piston line pressure towards the trailing side of the pad.
This article presents an overview of the acoustics of friction by covering friction sounds, friction-induced vibrations and waves in solids, and descriptions of other frictional phenomena related to acoustics. Friction, resulting from the sliding contact of solids, often gives rise to diverse forms of waves and oscillations within solids which frequently lead to radiation of sound to the surrounding media. Among the many everyday examples of friction sounds, violin music and brake noise in automobiles represent the two extremes in terms of the sounds they produce and the mechanisms by which they are generated. Of the multiple examples of friction sounds in nature, insect sounds are prominent. Friction also provides a means by which energy dissipation takes place at the interface of solids. Friction damping that develops between surfaces, such as joints and connections, in some cases requires only microscopic motion to dissipate energy. Modeling of friction-induced vibrations and friction damping in mechanical systems requires an accurate description of friction for which only approximations exist. While many of the components that contribute to friction can be modeled, computational requirements become prohibitive for their contemporaneous calculation. Furthermore, quantification of friction at the atomic scale still remains elusive. At the atomic scale, friction becomes a mechanism that converts the kinetic energy associated with the relative motion of surfaces to thermal energy. However, the description of the conversion to thermal energy represented by a disordered state of oscillations of atoms in a solid is still not well understood. At the macroscopic level, friction interacts with the vibrations and waves that it causes. Such interaction sets up a feedback between the friction force and waves at the surfaces, thereby making friction and surface motion interdependent. Such interdependence forms the basis for friction-induced motion as in the case of ultrasonic motors and other examples. Last, when considered phenomenologically, friction and boundary layer turbulence exhibit analogous properties and, when compared, each may provide clues to a better understanding of the other.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Synchronous-CDMA (S-CDMA) techniques are protected against co-channel interference by employing orthogonal codes. In an actual mobile radio environment, however, multipath may cause the orthogonality of S-CDMA signals to suffer from the increased cross correlation. In this scenario, multiuser detection is imperative to recover the orthogonality of the code. Liu and Xu (see Proc. 29th Asilomar Conf. on Signals, Systems and Computers, 1996) have proposed a blind-estimation scheme that provides closed-form estimates of the signature waveforms by exploiting the structure information of the data output. The approach is deterministic in the sense that noise or signal statistics are not required for the estimation. However the estimation utilizes only users' code information. We present a modified method that uses the known information of the pulse shaping filter as well as code information to improve the signature waveform estimates. We then extend this approach to overloaded systems by employing smart antennas.
Blind channel identification has been a popular research subject in recent years. We introduce the concept of knowledge-based blind channel identification. By relying on known information such as the pulse shaping filter and the antialiasing filter responses, the performance of channel identification and equalization can be significantly enhanced in digital communication systems. We present two simple methods: one in time-domain and one in frequency domain. Our simulation results demonstrate the performance of these two approaches.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Tests are reported on composite slabs with trapezoidal sheeting and longitudinal reinforcing bars above the troughs. The contribution from this reinforcement to resistance to longitudinal shear is found to be substantial. Analyses of the results lead to a design method that allows for it. It may not be possible to take full advantage in the design of this extra resistance, because the predicted deflection in service may then become excessive. ::: ::: An appendix gives an elastic–plastic model that accurately predicts the deflection of the slabs just before failure. A list of the principal nomenclature is included.
In recent years, composite slab has received utmost demand as a floor ::: system in the construction industry. The composite slab is an economical type of ::: structure and able to accelerate the construction process. Basically, the ::: composite slab can be casting by using a combination of corrugated steel deck ::: and normal concrete in which selfweight represents a very large proportion of ::: the total action. Therefore, foamed concrete become an attractive alternative to ::: be utilized as a replacement of normal concrete. However, foamed concrete has ::: high flexibility due to the presence of large amount of air-void and low modulus ::: elasticity. It may result in vibration responses being greater. Hence, this ::: experimental study investigates the vibration responses of composite slab made ::: of corrugated steel deck and foamed concrete. The specimens were prepared ::: with dimension of 750mm width, 1600mm length and 125mm thickness. The ::: hammer-impact test was conducted to obtain the acceleration-time history. The ::: analysis revealed that the first natural frequency is around 27.97Hz to 40.94Hz, ::: while the maximum acceleration reaches 1.31m/s2 to 1.88m/s2. The first mode ::: shape depicts normal pattern and favourable agreement of deformation.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This paper’s thesis of human agency derived from the South Carolina Successful School Principalship Project’s (SCSSPP) findings. In these schools, principals had leveraged a variety of schoolwide initiatives to enact the vision that all students would be successful despite their rurality and poverty. These findings were the underlying design for two regional cross-district pilot programs. Known as Leadership 2.0 and Leadership 3.0, the development of agency was constructed through cognitive coaching and based on principles of adult learning. Initial evaluation of participants’ first year reactions show consistently high perceptions of all aspects of the principles used for their professional learning.
This article provides a context for understanding how social networks among teachers support or constrain school improvement in terms of instructional practice, professional development, and educational reform. It comments on the articles in this special issue, summarizing their contributions to the field. This analysis reveals several important lessons including the finding that teachers’ social networks can be leveraged to work toward positive change, and yet teachers’ social networks may also thwart change. Moreover, the architecture of teachers’ social networks may change during the process of reform. Implications for further research are discussed.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Psychoacoustical tuning curves and narrow‐band masking were measured in normal and groups of moderately hearing‐impaired observers (conductive, otosclerosis, noise‐induced, and degenerative). The SPL of pure tones needed to just mask an intermittent 4‐kHz tone at 10 dB SL was measured as a function of the masker's frequency. Results support Schorn, Wurzer, Zollner, and Zwicker [Laryngol. Rhinol. 56, 121 –127 (1977)] and show wider tuning curves for the noise‐induced and degenerative groups than for the other groups. In the same observers, thresholds for 600‐ms pure tones were measured as a function of frequency in the presence and absence of a continuous 40‐dB‐SL narrow‐band noise centered at 4 kHz. Results show an enlarged upward spread of masking only for the noise induced and degenerative groups. However, at equal SPL the differences between observers with normal hearing and those with cochlear impairment were considerably reduced. [Work supported by Rotary Foundation and Deutsche Forshungsgemeinschaft...
Recent studies of frequency analysis in listeners with normal hearing and in those with sensorineural hearing losses are reviewed and compared with related physiological data. These studies suggest that it is now possible to obtain detailed audiological or psychoacoustic data for human listeners that closely parallel physiological data obtained in eighth nerve recordings from animals. Implications of these developments for future research with impaired listeners are discussed.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Oxygen converting of hot metal (LD/BOF) is contemplated as an object of simulation. Oxygen converting is a highly complex thermo-chemical process comprising a series of matter and energy transformation and transportation steps that makes the simulation very challenging. The basic principles of CONSIM 5 oxygen converter simulator are presented. Simulator is a comprehensive combination of a physical model with several empirical submodels describing all properties and processes that affect the final result of a converter blow, final mass and composition of steel, slag, dust and converter gas as well as the end temperature of steel. CONSIM simulator is used for simulation of series of high and low carbon steel blows. Simulated steel temperatures, oxygen consumption, blow time and iron oxide content of slag are compared with measured values. Problems of simulation and requirements for quantitative simulation of oxygen converter process are discussed.
A mathematical model for simulating the interdendritic solidification of low-alloyed and stainless steels is presented based on thermodynamic and diffusion calculations made in one volume element in the mushy zone. The method involves the determination of stable phases (ferrite, austenite, liquid, and FeMnS) as well as their fractions and compositions at any temperature during solidification. The model was tested by comparing calculations with experiments, and reasonable agreement was demonstrated. The model also includes a routine for predicting the liquid undercooling caused by solute accumulation ahead of the dendrite tips.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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My intention is to present some results related to the construction of coherent states [Perelomov, 1987] in a Hilbert space whose elements are cohomology classes. Such spaces appear in twistor theory and they have very important physical aplications as the quantum spaces of massless particles. This work is a small part of my doctoral thesis which will be published soon. It contains details and proofs of all facts I mention below.
L'article fournit la description complete des espaces de phase pour les particules sans masses, avec differentes helicites, Nous donnons une formule explicite pour les noyaux reproduisants des espaces d'Hilbert en question. Nous exhibons une symetrie entre produits scalaires et noyaux reproduisants directement reliee au propagateur des twisteurs.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We performed Johnson noise thermometry (JNT) using an integrated quantum voltage noise source (IQVNS) that generates pseudorandom noise with an RMS value determined by the product of the flux quantum, the clock frequency of IQVNS, $f_{\mathrm{clk}}$ , and a calculable coefficient. The working principle is different from the conventional QVNS. The waveform of the IQVNS was analyzed thoroughly, and the source checked to see that it worked properly as intended, particularly in regard to its applicability as a reference for JNT measurements. The thermal noise power of a resistor at the triple point of water was measured with the IQVNS to derive a value of the Boltzmann constant.
This paper gives the 2010 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. The 2010 adjustment takes into account the data considered in the 2006 adjustment as well as the data that became available from 1 January 2007, after the closing date of that adjustment, until 31 December 2010, the closing date of the new adjustment. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2010 set replaces the previously recommended 2006 CODATA set and may also be found on the World Wide Web at physics.nist.gov/constants.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Good modelling of the axial compressive stress–strain behaviour of confined reinforced-concrete (RC) columns is necessary for the structural analysis and design to assess their strength and ductili...
Most existing studies conducted on fiber-reinforced polymer (FRP)-confined concrete have considered circular and square concrete columns, while limited studies have considered columns with rectangular sections. Studies have confirmed that the circular cross-sections exhibited higher confinement effectiveness, whereas in the case of non-circular cross-sections the efficiency of FRP confinement decreases with an increase of the sectional aspect ratio and there is no significant increase, particularly for columns with the aspect ratio of 2.0. As recently suggested by researchers, to significantly increase the effectiveness of FRP-confinement for these columns involves changing a rectangular section into an elliptical or oval section. According to the literature, most of the existing confinement models for FRP-confined concrete under axial compression have been proposed for columns with circular and rectangular cross-sections. However, modeling of the axial strength and strain of concrete confined with FRP in elliptical cross-sections under compression is limited. Therefore, this paper provides new expressions based on limited experimental data available in the literature. For a sufficient amount of FRP-confinement, the threshold value was proposed to be 0.02. Finally, the accuracy of the proposed model was verified by comparing its predictions with the same test database, together with those from the existing models.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Zinc Oxide nanoparticles' thick film sensors doped with tungsten,has been developed and its response towards alcohol has been measured. The nanoparticles were synthesised by the chemical combustion technique and characterised by XRD, FESEM and EDS. It was established that the nanoparticles exist in a hexagonal system in a primitive lattice with no other impurities. A study on the sensing performance of the sensors hence prepared to the three primary alcohols has been carried out with the help of a new index which we call rate of response (sensitivity/sensing time). The sensors exhibit rate of responses as high as 22%/s with a sensitivity of around 80% with good selectivity and reproducibility.
Volatile methyl compounds are formed by the majority of elements standing up to six places before a rare gas, so that as a class they represent all groups and periods of the Periodic System with the exception of Group I. Accordingly, the volatile methyls provide a particularly suitable class of compounds for a comparative study of the covalent bonds which the metals and non-metals concerned form with carbon; and this study in turn throws light on the magnitudes of the internal excitation energies possessed by these elements when engaged in covalent bonding. Former approaches to this problem have been almost entirely theoretical. For convenience, the term" metal-carbon bond" will be used throughout this paper to denote all bonds of the type stated, whether the element linked to carbon is a metal or not.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This article explores the application of data-driven machine translation (MT) to sign languages (SLs). The provision of an SL MT system can facilitate communication between Deaf and hearing people by translating information into the native and preferred language of the individual. In this paper we address data-driven SL MT predominantly for Irish SL (ISL) but also for German SL (DGS/Deutsche Gebardensprache). We take two different purpose-built corpora to feed our MaTrEx MT system and in a set of experiments translating both to and from the SLs, we investigate the effects of SL data on statistical MT (SMT). Exploiting the bidirectionality of the MaTrEx system, we demonstrate how additional modules, such as recognition and SL animation, can potentially build a full SL MT model for spoken and SL communication in addition to promising evaluation scores. A secondary focus of the article is on the two main issues affecting SL MT, those of transcription and evaluation. We offer a discussion on both these common problems before concluding.
We discuss the problems of translating English to Sign Language in the ViSiCAST project. An overview of the language-processing component of an English-Text to Sign-Languages translation system is described focusing upon the inherent problems of knowledge elicitation of sign language grammar and its implementation within a HPSG framework.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In this paper, we present a comparative study of three distributed strategies for task allocation in a multirobot system. The objective is to determine the course of action for each robot and the targets it needs to service. A theoretical section is provided to support the dynamics of these techniques and some of the results. The first technique is a neural network-based approach, known as self-organizing map (SOM), that assigns targets to the robot on the basis of competition. The second technique is a combinatorial technique, known as the Hungarian method for solving assignment problems. The third technique is an integer linear programming-based optimization approach that tries to minimize the cost of task allocation. By implementing these three techniques, we observed that SOM tends to yield better results in terms of cost of assignment and execution time, but suffers from lack of fairness and workload balancing. In contrast, the other two methods fulfill the two criteria, but at the expense of a relatively higher cost.
It is important to know the orientation of the robot in coordination. Because it is useful for making maps that are uniform and can be matched to a particular area. In this paper, we discuss how the robots can uniformly face direction. With the assisted compass sensor to determine the orientation of the robot. True-North became a reference point for robots to equalize orientation. We conducted this experiment on 2 robots and got a relatively small error value. The value of error obtained by robot 1 of 2, 05% and robot 2 obtained an error value of 1, 33%.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Although the success of online encyclopedias such as Wiki-pedia is indisputable, researchers have questioned usefulness of Wikipedia in educational settings. Problems such as copy&paste syndrome, unchecked quality, or fragmentation of knowledge have been recognized as serious drawbacks for a wide spread application of Wikipedia in universities or high schools. In this paper we present a Wiki-based encyclopedia called Austria-Forum that aims to combine openness and collaboration aspects of Wikipedia with approaches to build a structured, quality inspected, and context-sensitive online encyclopedia. To ensure tractability of the publishing process the system focuses on providing information within a local Austrian context. It is our experience that such an approach represents a first step of a proper application of online encyclopedias in educational settings.
Usability specialists were better than non-specialists at performing heuristic evaluation, and “double experts” with specific expertise in the kind of interface being evaluated performed even better. Major usability problems have a higher probability than minor problems of being found in a heuristic evaluation, but more minor problems are found in absolute numbers. Usability heuristics relating to exits and user errors were more difficult to apply than the rest, and additional measures should be taken to find problems relating to these heuristics. Usability problems that relate to missing interface elements that ought to be introduced were more difficult to find by heuristic evaluation in interfaces implemented as paper prototypes but were as easy as other problems to find in running systems.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Reshock and release experiments performed on fused quartz over the stress range 13 to 21 GPa indicate the onset of a low to high density phase change at 13 GPa. The rapid release structure observed suggests unloading from a frozen mixed phase, while transformation rate effects are believed to be responsible for the dispersive reshock structure observed. Complete release experiments combined with quenched shock recovery experiments would be useful in addressing kinetics of the reverse phase transformation.
Under elastic shock compression silica glass exhibits a very specific behaviour. A shock propagating inside a material is usually seen as the propagation of a discontinuity. However in silica glass, shocks are unstable and lead to the propagation of a ramp wave where the shock front becomes gradually larger over time. Ramp waves were already reported in the literature, however their origin remain uncertain. This work presents an original study combining laser shock-induced experiments and molecular dynamics simulation aiming to improve the understanding of the mechanisms involved. Experimental ramp waves were directly observed using shadowgraphy technique allowing for an estimation of the head and tail velocities. Molecular dynamics simulations were carried out in order to reproduce ramp waves and to gain insight into the material properties. Ramp waves were observed for both elastic and plastic shockwaves. In the latter case, the plastic waves were preceded by an elastic ramp precursor. The sound speed, related to the material compressibility, was found to decrease with increasing pressure, as observed experimentally for quasi-static hydrostatic loading, thus providing an explanation for the instabilities that lead to the propagation of ramp waves.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Mn-doped black pigments CuMnxCr2-xO4(x=0, 0.05, 0.10, 0.15, 0.20 and 0.25) were synthesized by precursor coprecipitation method, and characterized by TG-DTA, XRD, FTIR and colorimetric analysis. The TG-DTA curves showed the crystal transition temperature was at about 800°C and mass loss ended at about 450°C. The infrared spectra displayed vibrations of spinel phase. XRD patterns displayed the characteristic peaks of the tetragonal phase spinel structure and proved that Mn substituted Cr in the spinel crystal lattice. L*a*b* analysis showed that all samples are black pigments with blue intensity, and Mn-doping could strengthen the black intensity and weaken the blue intensity of such black pigments.
Decomposition of mixed Cu-Fe-Cr hydroxycarbonates was investigated by thermal analysis and in situ XRD and FTIR. TGA and DTA showed that increased preheating temperature removes modifying anions and decreases the spinel crystallization temperature. A disordered oxide phase containing carbonate is initially formed. The carbonate contents and crystallization temperature decreases depend on the Fe3+/Cr3+ ratio. The residual anion content may affect interlayer and interblock distances in this amorphous phase, changing the spinel crystallization temperature. Understanding the modifying anion effects on the spinel crystallization makes it possible to select the thermal treatment.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A comprehensive analysis was conducted to develop DC characteristic equations for single-inductor dual-output (SIDO) boost converters and SIDO bipolar converters. From the analysis results, it was discovered, contrary to conventional thinking, that the SIDO boost converters can step-down one of the output voltages. And the SIDO bipolar can also step down the positive output voltage previously deemed not possible. These findings extend the application ranges of both converter types, e.g., both types can possibly be used in the applications where a single lithium-ion battery is deemed not possible previously. Experimental results validated the findings and the analytical results.
A load-dependant peak-current control single-inductor multiple-output (SIMO) DC-DC converter with hysteresis mode is proposed. It includes multiple buck and boost output voltages. Owing to the adaptive adjustment of the load-dependant peak-current control technique and the hysteresis mode, the cross-regulation can be minimized. Furthermore, a new delta-voltage generator can automatically switch the operating mode from pulse width modulation (PWM) mode to hysteresis mode, thereby avoiding inductor current accumulation when the total power of the buck output terminals is larger than that of the boost output terminals. The proposed SIMO DC-DC converter was fabricated in TSMC 0.25 mum 2P5M technology. The experimental results show high conversion efficiency at light loads and small cross-regulation within 0.35%. The power conversion efficiency varies from 80% at light loads to 93% at heavy loads.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Measurements made in a laser heated diamond-anvil cell are reported that extend the melting curve of Xe to 80 GPa and 3350 K. The steep lowering of the melting slope (dT/dP) that occurs near 17 GPa and 2750 K results from the hybridization of the 5p-like valence and 5p-like conduction states with the formation of clusters in the liquid having icosahedral short-range order (ISRO).
The noble gases are elements of broad importance across science and technology and are primary constituents of planetary and stellar atmospheres, where they segregate into droplets or layers that affect the thermal, chemical, and structural evolution of their host body. We have measured the optical properties of noble gases at relevant high pressures and temperatures in the laser-heated diamond anvil cell, observing insulator-to-conductor transformations in dense helium, neon, argon, and xenon at 4,000-15,000 K and pressures of 15-52 GPa. The thermal activation and frequency dependence of conduction reveal an optical character dominated by electrons of low mobility, as in an amorphous semiconductor or poor metal, rather than free electrons as is often assumed for such wide band gap insulators at high temperatures. White dwarf stars having helium outer atmospheres cool slower and may have different color than if atmospheric opacity were controlled by free electrons. Helium rain in Jupiter and Saturn becomes conducting at conditions well correlated with its increased solubility in metallic hydrogen, whereas a deep layer of insulating neon may inhibit core erosion in Saturn.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In this paper we study the inuence of semantics in the Text Categorization (TC) and Information Retrieval (IR) tasks. The K Nearest Neighbours (K-NN) method was used to perform the text categorization. The experimental results were obtained taking into account for a relevant term of a document its corresponding WordNet synset. For the IR task, three techniques were investigated: the direct use of a weighted matrix, the Singular Value Decomposition (SVD) technique in the Latent Semantic Indexing (LSI) model, and the bisecting spherical k-means clustering technique. The experimental results we obtained taking into account the semantics of the documents, allowed for an improvement of the performance for the text categorization whereas they were not so promising for the IR task.
Geographical entities often appears in very different forms in text collections, such as when a foreign name is used instead of the English one, or when the citation of some region or place omits the name of a larger geographical entity containing them. This is a known problem in the field of Information Retrieval. The use of an ontology like WordNet can help in addressing this issue. In this paper we propose an automatic method to expand the geographical terms in queries by using the WordNet ontology and another method that expands the terms during the indexing phase. The proposed methods exploits the synonymy, meronymy and holonymy relationships provided by WordNet, together with some information extracted from the gloss.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Surface adhesion forces in few layers of layered transition metal dichalcogenides (ReS 2 , NbS 2 , n-type WSe 2 , MoS 2 , p-type MoSe 2 , TaS 2 ) hexagonal BN (hBN) and graphene were determined using atomic force microscope with conducting silicon tip in dark and under illumination to identify material for integrated optical sensor in NEMS/MEMS switches. In all cases the surface adhesion forces increased under illumination. WSe 2 , an indirect band gap with 1.66 eV energy, showed the largest change of ∼165% in its adhesion force. Hexagonal BN, a wide band gap energy material of 5.5 eV, showed the smallest change of 7.2% comparable to changes in our control samples of 90 nm SiO 2 on Si and 100 nm Au on SiO 2 /Si. NbS 2 and graphene, samples with the smallest energy band gaps, respectively showed 54.8% and 8.4% increase in surface adhesion forces under illumination.
In order for the rapidly emerging field of MicroElectroMechanical Systems (MEMS) to meet its extraordinary expectations regarding commercial impact, issues pertaining to how they fail must be understood. We identify and address failure modes common to a broad range of MEMS actuation systems, including adhesion (stiction) and friction-induced failures caused by improper operational methods, mechanical instabilities, and electrical instabilities. Demonstrated methods to mitigate these failure modes include implementing optimized designs, model-based operational methods, and chemical surface treatments.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We maximized the information transmission for an integrating photosensor by optimizing the integration time. As a case study, experimentally determined reset, readout and photocurrent shot noise was used to determine the capacity of a differential active pixel sensor as a function of illumination level and integration time. Experimentally derived data show that the information rate is poor at both small and large integration times, with a maximum information rate occurring between these extremes. This maximum occurs at different integration times for different illumination levels and is used to determine the optimal integration time for the sensor.
Noise measurements of the 1/f noise in PMOS and NMOS transistors for analog applications are reported under wide bias conditions ranging from subthreshold to saturation. Two "low noise" CMOS processes of 2 /spl mu/m and 0.5 /spl mu/m technologies are compared and it is found that the more advanced process, with 0.5 /spl mu/m technology, exhibits significantly reduced 1/f noise, due to optimized processing. The input referred noise and the power spectral density (PSD) of the drain current 1/f noise are modeled in saturation as well as in subthreshold and are compared with the common empirical approaches such as the SPICE models. The results of this study are useful to the design and modeling of 1/f noise of CMOS analog circuits.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The convective heat transfer coefficient during deep-fat frying of potatoes was determined at different temperatures. The temperature, 0.1 cm below the top and bottom surfaces of a 0.05×0.05×0.005 m potato sample was monitored over time. The thermal conductivity and specific heat of the sample were expressed as a function of time, and the data were analyzed using the heat transfer equation with an explicit finite difference method. Crust formation occurred primarily at the bottom surface of the potato slice. Therefore, the frying was examined at the bottom surface; before and after the crust formation. The convective heat transfer coefficient ranged between 300 to 335 W / m 2 °C for the top, and 450 to 480 W/m 2 °C for the bottom surface before crust formation. After crust formation, it varied between 70 to 150 W/m 2 °C for the bottom surface within the studied temperature range of 150 to 190 °C.
Jerusalem artichoke has been cultivated in various regions without any special breeding technique. As a food, Jerusalem artichoke has a characteristic flavour and functional ingredients including inulin, other dietary fibers, minerals and traces of polyphenol. The production of chips from Jerusalem artichoke was examined in this study because it contains high amount of inulin. Inulin gives health promoting effects especially for the people suffering from diabetes. Firstly,chips production from Jerusalem artichoke was studied in the scope of properties like moisture, oil, color, texture, sensory. After cleaning, tubers prepared in specified size and slices were cooked in the deep fat fryer or microwave oven. The best results obtained for frying and microwave oven application of Jerusalem artichoke were obtained at 180℃ for 240s treatment time and at 600 W for105s, respectively.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In this paper, we introduce a pipe interface that recognizes touch on tone holes by the resonances in the pipe instead of a touch sensor. This work was based on the acoustic principles of woodwind instruments without complex sensors and electronic circuits to develop a simple and durable interface. The measured signals were analyzed to show that di!erent fingerings generate various sounds. The audible resonance signal in the pipe interface can be used as a sonic event for musical expression by itself and also as an input parameter for mapping di!erent sounds.
This paper introduces the design of a handheld musical input device that produces control data by measuring, and analyzing, the resonances of carefully tuned pipes. The device provides input control information to several virtual reed instruments running in parallel, responsible for producing the sound. Inspired by the khaen, a musical instrument from Northeast Thailand and Laos, the controller consists of a row of acoustic tubes, with finger holes that change the tube's resonance when covered. Each tube is equipped with both a microphone recording the change in pressure variations at a set location along the tube. The mic outputs are mixed, and input to the computer via the mic level audio ports, allowing the controller to interface very reliably (and conveniently) to most laptop computers.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Kidder-Parker Architects' and Builders' Handbook pdf ebook ctn4z free download By The Late Frank E. , C.E., Ph. D. Kidder · ctn4z · Eight Tales for Eight Nights:. Up for sale is KidderParker Architects & Builders Handbook 1950 18th Edition Engineers Contractors with some wear as seen in pictures. Any. -by-american-architects/-/john-wiley-and-sonsincorporated/9780471468455 /textbook/architects-and-builders-handbook/frank-e-kidder-andharry-parker/.
Government regulations are semi-structured text documents that are often voluminous, heavily cross-referenced between provisions and even ambiguous. Multiple sources of regulations lead to difficulties in both understanding and complying with all applicable codes. In this work, we propose a framework for regulation management and similarity analysis. An online repository for legal documents is created with the help of text mining tool, and users can access regulatory documents either through the natural hierarchy of provisions or from a taxonomy generated by knowledge engineers based on concepts. Our similarity analysis core identifies relevant provisions and brings them to the user's attention, and this is performed by utilizing both the hierarchical and referential structures of regulations to provide a better comparison between provisions. Preliminary results show that our system reveals hidden similarities that are not apparent between provisions based on node content comparisons.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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An analysis was made of cantilever beam specimens used for crack propagation studies, Included in this analysis were the effects of a plastic zone at the crack tip, beam rotation, and the viscoelastic response of the material. This analysis showed that application of a constant bending moment to the specimen rather than a constant load provides a test in which the strain energy release rate,G, is independent of crack length. Other advantages of this test configuration are that corrections for shear or beam rotation effects are not necessary. Results of this test on both glass and ceramics are reported.
A ZBLAL fluoride glass produced at NRL was characterized mechanically both in bulk and fiber forms. Fracture toughness measurements gave Ki values of 0.38 ± 0.05 MPa.m1/2, about 1/2 that of Si0 2 glasses. Flexural strength of machined bars of the current ZBLAL glasses was about 60MPa, about 80% of similarly finished silicate glasses. While the fluoride glass has lower strength than Si0 2 glass, it had much less slow crack growth, which should give it a longer useful life over a range of stresses. Although the average tensile strength of fibers from initial fiber drawing trials was only about 170 MPa, fractographic examinations indicated that the useful strength of this fiber could be raised considerably with improved processing.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In this work a method to estimate the contribution to tidal residues originated by non-linear interaction between tides and low frequency phenomena is presented. In order to perform the validation, the method is applied on current data series taken from the Strait of Gibraltar which allows us to find a clear relationship between current tidal residues and low frequency fluctuations in the flow, which may be explained in terms of the non-linear interaction between tidal and sub-inertial signals in the current velocity.
Summary ::: ::: The intensive application of the conventional harmonic method of analysis to the distorted tidal regime of the Thames estuary leads to the identification of some 54 ‘new’ tidal lines of significant amplitude, and hence to an extended harmonic method (E.H.M.) of analysing and predicting shallow water tides. The improvement in predictions is evaluated and compared with the Doodson harmonic shallow water process. ::: ::: ::: ::: The frequency dependence and coherence of residual energies in the data sets are examined. They are a maximum in the 2 c.p.d. band, and are shown to be consistent with short bursts of phase modulation of the tidal line by meteorological disturbances. The typical ‘hump’ in the spectrum associated with this phenomenon is compared with the tidal ‘cusp’ suggested by Munk et al., leading to the possibility that tides are not strictly a time-stationary phenomenon.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A split-gate (SG) flash memory cell has been embedded in a 65nm ground-rule high performance (HP) CMOS logic process with copper low K interconnects. A gate spacer processing sequence self-aligned (SA) process provides a reliability-robust cell and high degree of modularity with one extra mask to form the SG structure. The proposed cell is optimized for minimum module area overhead, high endurance and can be integrated in a standard stacked gate Technology in a modular way.
Compressed Sensing (CS) can be introduced in the processing chain of a sensor node as a mean to globally reduce its operating cost, while maximizing the quality of the acquired signal. We exploit CS as a simple early-digital compression stage that performs a multiplication of the signal by a matrix. The operating costs (e.g., the consumed power) of such an encoding stage depend on the number of rows of the matrix, but also on the value and position of the rows’ coefficients. Our novel design flow yields optimized sparse matrices with very few rows. It is a non-trivial extension of the rakeness-based approach to CS and yields an extremely lightweight stage implemented by a very small number of possibly signed sums with an excellent compression performance. By means of a general signal model we explore different corners of the design space and show that, for example, our method is capable of compressing the signal by a factor larger than 2.5 while not considering 30% of the original samples (so that they may not be acquired at all, leaving the analog front-end and ADC stages inactive) and by processing each of the considered samples with not more than three signed sums.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A cylindrical Fresnel zone antenna as a candidate for a base station in wireless indoor LAN systems is described. An arbitrary angle-tilted fan beam in azimuth can be achieved by moving the position of the strip dipole feed at the cylinder center. A simple theory based on the diffraction integral is developed which predicts the antenna radiation characteristics. The antenna fabrication and measurement are carried out at 9 GHz with good agreement between calculated and measured results.
—ConicalinshapeFresnelzone(CFZ)lensofflatdielec-tricringsisintroducedandstudiedinthisresearch.ItiscontrastedtoaplaneFresnelzone(PFZ)lens,aCFZlensofconicalringsandarefractiveplane-hyperbolic(PH)lens.Forthesameaperturedi-ameterofabout25mmandfocallengthof30mm,a229-GHzCFZlensofflatringswitha30-degreeopeningsemi-anglesignificantlysurpassesthePFZ and PH lensesin focusinggain and efficiency.Also,itexhibitsasubwavelength transverseresolutionandmuchhigheraxialresolution.Thecited30-degreeflat-ringCFZlenshas4.5timessmallerweightthanthePHlens,andiseasytomanufac-tureasaplanemultilayerpackagebymeansofprecisemachiningor modernphotolithographicandother microelectronictechnolo-gies.Nevertheless,theCFZ lensbenefitsover thecorrespondingPH refractive lensareattained on account of smaller frequencybandwidthandbigger lensthickness.Thenewflat-ringCFZlensdesign can be applied in accurate imaging systemsor for a cre-ation oflight and efficient microwave,terahertzand opticallensantennas.Index Terms—Focusing, Fresnel zone lens, lens, lens antenna,mm/sub-millimeter lens.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We present methods for finding common fixed points of finitely many firmly nonexpansive mappings on a Hilbert space. At every iteration, an approximation to each mapping generates a halfspace containing its set of fixed points. The next iterate is found by projecting the current iterate on a surrogate halfspace formed by taking a convex combination of the halfspace inequalities. This acceleration technique extends one for convex feasibility problems (CFPs), since projection operators onto closed convex sets are firmly nonexpansive. The resulting methods are block iterative and, hence, lend themselves to parallel implementation. We extend to accelerated methods some recent results of Bauschke and Borwein [SIAM Rev., 38 (1996), pp. 367--426] on the convergence of projection methods.
Recently, S. Reich and S. Simons provided a novel proof of the Kirszbraun-Valentine extension theorem using Fenchel duality and Fitzpatrick functions. In the same spirit, we provide a new proof of an extension result for firmly nonexpansive mappings with an optimally localized range.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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This paper presents the development of an ultrasonic tomography system for multiphase flow imaging. Ultrasonic tomography (UT) modality has a hard-field sensing principle which makes feasible to measure liquid-gas, liquid-liquid and liquid-solid flow composition within a pipe vessel. The sensor configuration for the UT system is discussed along with its signal conditioning circuitry and image reconstruction technique. The feasibility of the system is experimentally carried out on a 100 mm acrylic pipe for a stratified multiphase flow measurement to reconstruct tomographic images.
We demonstrate the use of Tikhonov regularisation as a data inversion technique to determine the velocity distributions of flowing liquid streams. Regularisation is applied to the signal produced by a nuclear magnetic resonance (NMR) flow measurement system consisting of a pre-polarising permanent magnet located upstream of an Earth's magnetic field NMR detection coil. A simple free induction decay (FID) NMR signal is measured for the flowing stream in what is effectively a 'time-of-flight' measurement. The FID signal is then modelled as a function of fluid velocity and acquisition time, enabling determination of the velocity probability distributions via regularisation. The mean values of these velocity distributions were successfully validated against in-line rotameters. The ability to quantify multi-modal velocity distributions was also demonstrated using a two-pipe system.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Digital divide research has benefitted from theories that account for unevenness between individuals, households, and geographic units in access to, and uses of information and communications technologies (ICTs). The objective of this paper is to explain and examine important digital divide theories, compare and contrast their major features, and identify appropriate methodologies to test them. Four theories examined are Adoption-Diffusion Theory (ADT), van Dijk's Theory of Digital Technology Access and Societal Impacts, Unified Theory of Acceptance and Use of Technology (UTAUT), and Spatially Aware Technology Utilization Model (SATUM). The theories are compared based on their independent and outcome factors, units of analysis, spatial components, and amount of scholarly literature. The methodologies utilized depend on sample size and range from varied regression and multinominal logit models to structured equation modeling, event history, and spatial analyses. The strengths and weaknesses of the digital divide theories are compared and can inform investigators on appropriate theoretical choice for particular settings.
1: Introduction.- 2: Origins, Growth, and Geographies of the Global Internet.- 3: Global Internet Censorship.- 4: Global E-Commerce.- 5: Global E-Government.- 6: Social Media.- 7: References
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Let $\Sigma_{\alpha=m}\;s_{\alpha}z^{\alpha},\;z\;{\in}\;{\mathbb{C}}^n$ be a unimodular m-homogeneous polynomial in n variables (i.e. $s_{\alpha}\;=\;1$ for all multi indices ), and let be a (bounded complete) Reinhardt domain. We give lower bounds for the maximum modules $sup_{z\;{\in}\;R\;\Sigma_{\alpha=m}\;s_{\alpha}z^{\alpha}$, and upper estimates for the average of these maximum moduli taken over all possible m-homogeneous Bernoulli polynomials (i.e. for all multi indices ). Examples show that for a fixed degree m our estimates, for rather large classes of domains R, are asymptotically optimal in the dimension n.
Let ℱ(R) be a set of holomorphic functions on a Reinhardt domain R in a Banach sequence space (as e.g. all holomorphic functions or all m-homogeneous polynomials on the open unit ball of ). We give a systematic study of the sets dom ℱ(R) of all z ∈ R for which the monomial expansion of every ƒ ∈ ℱ(R) converges. Our results are based on and improve the former work of Bohr, Dineen, Lempert, Matos and Ryan. In particular, we show that up to any ε > 0 is the unique Banach sequence space X for which the monomial expansion of each holomorphic function ƒ converges at each point of a given Reinhardt domain in X. Our study shows clearly why Hilbert's point of view to develop a theory of infinite dimensional complex analysis based on the concept of monomial expansion, had to be abandoned early in the development of the theory.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Purpose – The Hermite collocation method of discretization can be used to determine highly accurate solutions to the steady‐state one‐dimensional convection‐diffusion equation (which can be used to model the transport of contaminants dissolved in groundwater). This accuracy is dependent upon sufficient refinement of the finite‐element mesh as well as applying upstream or downstream weighting to the convective term through the determination of collocation locations which meet specified constraints. Owing to an increase in computational intensity of the application of the method of collocation associated with increases in the mesh refinement, minimal mesh refinement is sought. Very often this optimization problem is the one where the feasible region is not connected and as such requires a specialized optimization search technique. This paper aims to focus on this method.Design/methodology/approach – An original hybrid method that utilizes a specialized adaptive genetic algorithm followed by a hill‐climbing ...
A non-linear mathematical model for displacement washing of pulp fibers with suitable boundary conditions is presented. Model equations are divided into two phases: particle phase and external fluid phase. The Hermite collocation method (HCM) is employed to solve the non-linear model equations. The validity and efficiency of the proposed model is demonstrated by comparing the numerical results with the experimental ones. Stability of the proposed method is checked by evaluating L2 and L? norms at different time intervals. Industrial parameters such as displacement ratio and wash yield have been calculated to check the validity of the model. Numerical values obtained from the model equations are presented in terms of 2D graphs.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We study multivariate time-series generated by coupled map lattices exhibiting spatio-temporal chaos and investigate to what extent we are able to estimate various intensive measures of the underlying system without explicit knowledge of the system dynamics. Using the rescaling and interleaving properties of the Lyapunov spectrum of systems in a spatio-temporally chaotic regime and paying careful attention to errors introduced by sub-system boundary effects, we develop algorithms that are capable of estimating the Lyapunov spectrum from time-series. We analyse the performance of these and find that the choice of basis used to fit the dynamics is crucial: when the local dynamics at a lattice site is well approximated by this basis we are able to accurately determine the full Lyapunov spectrum. However, as the local dynamics moves away from the space spanned by this basis, the performance of our algorithm deteriorates.
We use a mix of temporal and spatial delay embedding techniques to carry out reconstruction and cross-prediction on a time series generated by a coupled map lattice. We find that spatio-temporal delay reconstructions give better predictability than standard methods using either time delays only or spatial delays only. We also observe that in all these cases it is completely infeasible to rigorously embed the original spatio-temporal system since this would require impractically large embedding dimensions. Despite this, it proves possible to make good short term predictions in embedding dimensions as low as 4. We discuss a possible explanation of this apparent paradox and briefly describe a tentative theoretical framework for reconstructing high-dimensional systems that this suggests.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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We consider the problem of estimating CPU (distance computations) and I/O costs for processing range and k-nearest neighbors queries over metric spaces. Unlike the specific case of vector spaces, where information on data distribution has been exploited to derive cost models for predicting the performance of multi-dimensional access methods, in a generic metric space there is no such a possibility, which makes the problem quite different and requires a novel approach. We insist that the distance distribution of objects can be profitably used to solve the problem, and consequently develop a concrete cost model for the M-tree access method [10]. Our results rely on the assumption that the indexed dataset comes from a metric space which is “homogeneous” enough (in a probabilistic sense) to allow reliable cost estimations even if the distance distribution with respect to a specific query object is unknown. We experimentally validate the model over both real and synthetic datasets, and show how the model can be used to tune the M-tree in order to minimize a combination of CPU and I/O costs. Finally, we sketch how the same approach can be applied to derive a cost model for the vp-tree index structure [8].
A genomic database consists of a set of nucleotide sequences, for which an important kind of query is the focal sequence alignment. The paper investigates two different indexing techniques, namely the variations of GNAT trees and M-trees to support fast query evaluation for local alignment, by transforming the alignment problem to a variant metric space neighborhood search problem.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The delay of a square SRAM array is dominated by the bit line delay due to the high capacitance per unit length attached to the bit line. Hence, SRAM arrays are usually longer in the word line direction. However, the word line delay also increases dramatically in a simple naive topology and can be a dominating factor when the word line dimension is much longer than that of the bit line. Therefore, word line optimization is an important part of SRAM delay optimization. Buffer insertion, which is commonly used for long interconnects, can also be used to improve word line delay. This paper proposes an approach to place and size the buffers to reduce word line and overall SRAM delay. The proposed methodology improves the read critical path delay by 15.7%, at the cost of only 5.26% extra area in a 128 Kbit SRAM.
Computer systems research is often inhibited by the availability of memory designs. Existing Process Design Kits (PDKs) frequently lack memory compilers, while expensive commercial solutions only provide memory models with immutable cells, limited configurations, and restrictive licenses. Manually creating memories can be time consuming and tedious and the designs are usually inflexible. This paper introduces OpenRAM, an open-source memory compiler, that provides a platform for the generation, characterization, and verification of fabricable memory designs across various technologies, sizes, and configurations. It enables research in computer architecture, system-on-chip design, memory circuit and device research, and computer-aided design.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In the context of a continuum theory of crystals with defects, one can define a particular list of invariants so that elements of this list do not change when the crystal is deformed elastically. Here we characterize (most of) the deformations which leave these elements unchanged and find that these “defect-preserving” deformations.strictly include the elastic deformations. This characterization allows a judgement of the completeness of the list of invariants. Furthermore it turns out that the defect-preserving deformations which are not elastic generally involve some kind of rearrangement, or slip, of the crystal lattice, and that if one admits such deformations in variational principles determining equilibria of the lattice, then the crystal is necessarily weak, in some sense; for example, the crystal may be able to equilibrate only simple pressure over its boundary.
We show that an abstract notion of defectiveness yields the slip mechanism of classic plasticity theory by reasoning in purely kinematical terms, and we catalogue the canonical forms of slip that occur in this way. There appears, in consequence, a precise version of the idea of elastic-plastic decomposition.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Distributions of droplet size, axial velocity and liquid flux have been measured downstream of a model inlet valve with a phase-Doppler velocimeter. The valve had a diameter of 40mm, a 45° bevelled edge and was arranged at the exit of a straight tube of inside diameter 34mm with the lifts of 2, 4 and 6mm. Suction was applied by a variable speed electric fan to simulate the intake stroke of a cylinder of 400cc displacement at 1200 RPM, with an air flow rate for the 4mm valve lift of 0.99m3/min, corresponding to the bulk velocity of 38m/s in the valve gap. Gasoline was supplied either by a commercial injector located 70mm from the valve or by its introduction on the surfaces of the valve and port. The injection of fuel with an open valve led to Sauter mean diameters between 80 and 1001.m, lower than the 130µm appropriate to the free unconfined spray. With 2mm valve lift, the spray emerged between angles of 10° to 70° to the horizontal axis and with larger valve lifts it emerged with narrow angle close to that of the valve head surface immediately upstream of the valve bevel, that is 25°. The introduction of fuel as a liquid streams led to a Sauter mean diameter of 240µm with the maximum flux emerging from the edges of the valve and seat bevels, at angles of 50° and 40° to the horizontal axis, respectively.
A comparatively inexpensive instrument has been developed for the measurement of local concentrations of gaseous fuel and evaluated in terms of its application to the flow in the cylinders of internal-combustion engines. It is based on the absorption of infrared light by hydrocarbons with computer tomography to provide spatially local information. This paper describes the instrument and its application to the flow in simple arrangements intended to represent the cylinders of an internal-combustion engine. The optical system comprised a helium-neon laser, a lead-selenium sensor, a chopper, an amplifier and a microcomputer. It can readily be modified to improve spatial resolution by monitoring the temporal fluctuations in the intensity of the laser beam, the error from which was reduced to less than 0.8% in the present experiment. A translation and rotation scanning method formed the basis for tomography and the spatial distribution of gaseous fuel was reconstructed by convolution. The instrument was applied to a simulation of the flow in a lean-burn gasoline engine with a cylinder made of quartz glass. The methane fuel was injected at the intake valve or 100 mm upstream of the valve to simulate evaporated fuel with steady airflow, and the port geometry provided swirl corresponding to ratios of 1.3 and 2.9. The cylindrical cylinder implied that the fibre location was adjusted to detect the laser light absorption at known positions along the light path. Distributions of the concentration of methane are presented by infrared light passing through hydrocarbons and computer tomography to provide spatially local information.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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In order to determine the radar cross section of a semi-infinite elliptic cone first the solution of the pertinent canonical boundary value problem in sphero-conal coordinates is derived. For this purpose one has to solve a two-parameter eigenvalue problem with two coupled Lame differential equations. The exact nose-on radar cross section of the semi-infinite elliptic cone has been evaluated for two orthogonal polarizations of the incident plane wave. In the degenerate case of a circular cone the known formula first deduced by Hansen and Schiff is obtained. The theoretical results also hold for the case of a plane angular sector which is another degenerate case of the elliptic cone.
The scattering and diffraction of a complex-source beam (CSB) by an acoustically soft or hard plane angular sector is treated by a rigorous spherical-multipole analysis in sphero-conal coordinates. By assigning a complex-valued radial source coordinate to the corresponding Green's function, the CSB is directed exactly towards the corner of the sector. Since the CSB can be interpreted as a localized plane wave, its interaction with the corner in the presence of the semi-infinite structure can be analyzed in detail. In opposite to the classical case of a non-localized incident plane wave, the resulting multipole series is strongly convergent and no summation techniques are necessary to obtain meaningful results. The numerical results include a convergence analysis, total near fields as well as scattered far fields and prove the applicability of this new approach.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Scholars of early Islamic history and texts suggest that early Muslim interest in its acclaimed Rock of Foundation, the Sakhra, was directly influenced by the Muslim assimilation and re-imagination of Jerusalem's religious significance to both Jews and Christians. The Sakhra's mythology developed through political and theological absorption and reaction to Jewish and Christian Jerusalem-centered sacred rock mythologies. The Even Shetiyah, Golgotha, and the Sakhra, three mythological rocks, symbolized more than just a natural connection to the divine. They each embodied or witnessed The Truth for their particular religious teachings and community, especially in the face of polemical opposition from other competing communities. By the time the Dome of the Rock was built, to protect one rendition of that stone, sacred Jerusalem stones proliferated and functioned as a multiplicity of competing and real rather than fictive "sites of memory." The focus of this essay is on those Rocks, the symbolism they absorb, and the function they play in the imagination of these late ancient communities, particularly as they jostled for spiritual advantage one against the other. Each sacred rock embodied the religious truths and self-proclaimed superiority of the community for whom that specific rock was sacred.
Introduction 1. Visual theory 2. God-gazing and homovisuality 3. Heterovisuality, face-bread and cherubs 4. Visual eros 5. Eyeing idols 6. Seeing sages Conclusion.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Igneous dikes buried beneath as much as 2 m of alluvium in the Mojave Desert of California were detected by the SEASAT L-band (23.5-cm wavelength) synthetic-aperture radar (SAR) in 1978. The roughness and dihedral configuration of the dikes are favorable to generation of strong radar echos. The soil-moisture levels in 1978 were likely below the critical 1% level. The other permissive conditions for radar penetration of a fine-grained and thin alluvial cover are present. Our findings suggest that subsurface features with potential tectonic or geomorphic significance may be revealed in other orbital radar images of semiarid terrains.
Land subsidence due to slow compaction sediments is one of the most dangerous cases in nature. Human activities such as removal of hydrocarbons are one of the environmental issues. While traditional mapping can determine the rate of subsidence factors in depression but according to the criteria and the cost of this type of mapping it always need to use modern techniques. Nowadays, one of the most advanced methods to obtain the reservoir subsidence in centimeter accurately is INSAR(Interferometry synthetic aperture radar) .The main purpose of this research is estimating and studying about one of oil fields, that the rate of subsidence is significant in it and in addition the main reasons of it has been studied. The results are consistent so much with the observed changes of field production data. The results show that the INSAR method can be used so extensively in industrial and research projects. We think the results of study the subsidence effect will be useful to detection of chemical properties variations the oil resources such as concentration, viscosity and other chemical properties.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Ignition and stabilization of pulverized coal combustion by plasma assist is investigated with a 10 kW plasma torch for three different kinds of coal, such as high, medium and low volatile matter coals. Not only high volatile matter coal but also low quality coal can be successfully burned with plasma assist. Research for volatile component of coal shows that a higher temperature field is necessary to extract the volatile matter from inferior coal, while their compositions are almost the same.
Experimental studies were carried out on a 600 MWe supercritical boiler that was ignited by the technology of less-oil ignition. The variation of steam temperature and pressure, wall temperature of heat exchange surfaces and combustion status were investigated. Test results demonstrated that the pulverized coal is able to be combusted fully and stably in the less-oil ignition combustor, and the wall temperature of the combustor remains less than 300°C. It was also shown that the wall temperature of heat exchange surfaces is also not overheated, which expands uniformly, and the rising rate of the steam temperature and pressure satisfies the requirement of operation rules. In addition, compared to the cases using conventional ignition techniques, the economical benefit by employing the technology of less-oil ignition is pronounced.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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A novel compact design of a fully printable chipless RFID tag and two near-field reading techniques for the designed tag are presented in this paper. The tag is made of two multiple slot-loaded rectangular patches. Slots with adjacent frequencies are placed alternately into two patches to reduce the mutual coupling between the slot resonators. The tag measurements are done for both proximity reading and slot card reading techniques. This single sided compact tag has higher data capacity and lower cost compared to the existing printable chipless tags. It can be incorporated in paper or plastic-based items such as ID cards, tickets and banknotes as an enhancement in security in a user friendly way.
The paper presents the design and development of a low cost chipless RFID system for secure near field data transfer. This system is ideal for use in credit cards and similar identification cards which are based on "data transfer by contact" which at present uses the conventional using integrated circuits (IC) or magnetic strips. The system consists of the design of a compatible low cost tag as well as the measurement set up using a metallic cavity. Using the presented technique it is easily possible to code 23 bits within the dimensions of a conventional credit card. Emphasis is given to security as well as larger data capability. It can be seen that the presented technique is robust and cost effective compared to the existing techniques and can be used as a viable alternative in identification cards based on data transfer by contact.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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The paper analyses the problem of beer bottles detection techniques on the beer bottles production line, uses digital image processing technique on the beer bottles online defect detection. The paper puts forward the designing ideas of the hardware, developing flow of the software and the algorithm of beer bottles detection. TMSDM642 is used to set up the real-time video processing system of the hardware .The hardware system is mainly composed of three parts: the part of memory, the part of the input and the part of the output. When beer bottles are put into the work area, the video images of the bottle-mouth and bottle-bottom will be gained by the CCD camera, firstly, preprocessing is used to eliminate video image noise. Secondly, the image segmentation algorithm is used to detect defects in video images. Lastly the goal of extracting defects will be accomplished. The experimental result indicated that this system may effectively exam the flaw or the unqualified beer bottles.
According to the characteristics of glass defects, through analyzing the advantages and disadvantages of the traditional BP algorithm, an improved BP neural network recognition algorithm is applied to the glass defect classification and character recognition. Experimental results show that compared with traditional BP recognition algorithm, convergence speed of the algorithm is fast and the identification of false positives is low.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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Intelligent video analysis is a problem of great importance for applications such as surveillance and automatic annotation. We present, in this paper, a hybrid, knowledge – based approach for object recognition in video sequences. Objects are modelled, in the signal level, through the visual descriptors defined by MPEG-7, the ISO standard for description of audiovisual content and in the semantic level, through the semantic relations defined by MPEG7. The method of video analysis is synopsised as follows: first, moving regions are extracted using an active contour technique. Second, visual descriptions of the moving regions are extracted and are matched with the ones defined for recognizable objects.
Efficient video content management and exploitation requires extraction of the underlying semantics, a non-trivial task associating low-level features of the image domain and high-level semantic descriptions. In this paper, a knowledge-assisted approach for extracting semantics of domain-specific video content is presented. Domain knowledge considers both low-level features (color, motion, shape) and spatial behavior (topological and directional information). During the preprocessing step, a set of over-segmented homogenous atom-regions is generated and their low-level and spatial descriptions are extracted. A genetic algorithm is then applied in order to find the optimal interpretation according to a specific domain conceptualization. The proposed approach was tested on the formula one, tennis and beach vacations domains showing promising results.
We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.
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