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we report on x - ray observations of the 5. 54 s transient magnetar xte j1810 - 197 using the xmm - newton and chandra observatories, analyzing new data from 2008 through 2014, and re - analyzing data from 2003 through 2007 with the benefit of these six years of new data. from the discovery of xte j1810 - 197 during its 2003 outburst to the most recent 2014 observations, its 0. 3 - 10 kev x - ray flux has declined by a factor of about 50 from 4. 1e - 11 to 8. 1e - 13 erg / cm ^ 2 / s. its x - ray spectrum has now reached a steady state. pulsations continue to be detected from a 0. 3 kev thermal hot - spot that remains on the neutron star surface. the luminosity of this hot - spot exceeds xte j1810 - 197 ' s spin down luminosity, indicating continuing magnetar activity. we find that xte j1810 - 197 ' s x - ray spectrum is best described by a multiple component blackbody model in which the coldest 0. 14 kev component likely originates from the entire neutron star surface, and the thermal hot - spot is, at different epochs, well described by an either one or two - component blackbody model. a 1. 2 kev absorption line, possibly due to resonant proton scattering, is detected at all epochs. the x - ray flux of the hot spot decreased by approximately 20 % between 2008 march and 2009 march, the same period during which xte j1810 - 197 became radio quiet.
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arxiv:1601.00757
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we have obtained data for 41 star forming galaxies in the muse atlas of disks ( mad ) survey with vlt / muse. these data allow us, at high resolution of a few 100 pc, to extract ionized gas kinematics ( $ v, \ sigma $ ) of the centers of nearby star forming galaxies spanning 3 dex in stellar mass. this paper outlines the methodology for measuring the ionized gas kinematics, which we will use in subsequent papers of this survey. we also show how the maps can be used to study the kinematics of diffuse ionized gas for galaxies of various inclinations and masses. using two different methods to identify the diffuse ionized gas, we measure rotation velocities of this gas for a subsample of 6 galaxies. we find that the diffuse ionized gas rotates on average slower than the star forming gas with lags of 0 - 10 km / s while also having higher velocity dispersion. the magnitude of these lags is on average 5 km / s lower than observed velocity lags between ionized and molecular gas. using jeans models to interpret the lags in rotation velocity and the increase in velocity dispersion we show that most of the diffuse ionized gas kinematics are consistent with its emission originating from a somewhat thicker layer than the star forming gas, with a scale height that is lower than that of the stellar disk.
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arxiv:1911.06070
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in this paper, we study self - dual gravity in the newman - penrose formalism. we specify the self - dual solution space from the newman - unti solutions. we show that the asymptotic symmetries of the self - dual gravity are still the ( extended ) bms symmetries. we transform the self - dual taub - nut solution into the newman - unti gauge in analytical form.
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arxiv:2203.17080
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in this work, we demonstrate a chinese classical poetry generation system called deep poetry. existing systems for chinese classical poetry generation are mostly template - based and very few of them can accept multi - modal input. unlike previous systems, deep poetry uses neural networks that are trained on over 200 thousand poems and 3 million ancient chinese prose. our system can accept plain text, images or artistic conceptions as inputs to generate chinese classical poetry. more importantly, users are allowed to participate in the process of writing poetry by our system. for the user ' s convenience, we deploy the system at the wechat applet platform, users can use the system on the mobile device whenever and wherever possible. the demo video of this paper is available at https : / / youtu. be / jd1r _ u9ta3m.
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arxiv:1911.08212
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large - area bilayer graphene ( bg ) is grown epitaxially on ru ( 0001 ) surface and characterized by low temperature scanning tunneling microscopy. the lattice of the bottom layer of bg is stretched by 1. 2 %, while strain is absent from the top layer. the lattice mismatch between the two layers leads to the formation of a moire pattern with a periodicity of ~ 21. 5 nm and a mixture of aa - and ab - stacking. the root3 x root3 superstructure around atomic defects is attributed to the inter - valley scattering of the delocalized pi - electrons, demonstrating that the as - grown bg behaves like intrinsic free - standing graphene.
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arxiv:1406.1094
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a signature changing spacetime is one where an initially riemannian manifold with euclidean signature evolves into the lorentzian universe we see today. this concept is motivated by problems in causality implied by the isotropy and homogeneity of the universe. as initially time and space are indistinguishable in signature change, these problems are removed. there has been some dispute as to the nature of the junction conditions across the signature change, and in particular, whether or not the metric is continuous there. we determine to what extent the colombeau algebra of new generalised functions resolves this dispute by analysing both types of signature change within its framework. a covariant formulation of the colombeau algebra is used, in which the usual properties of the new generalised functions are extended. we find that the colombeau algebra is insufficient to preclude either continuous or discontinuous signature change, and is also unable to settle the dispute over the nature of the junction conditions.
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arxiv:gr-qc/0004057
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the gauge theory approach to the geometric langlands program is extended to the case of wild ramification. the new ingredients that are required, relative to the tamely ramified case, are differential operators with irregular singularities, stokes phenomena, isomonodromic deformation, and, from a physical point of view, new surface operators associated with higher order singularities.
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arxiv:0710.0631
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there are constructed exact solutions of the quantum - mechanical dirac equation for a spin s = 1 / 2 particle in riemannian space of constant negative curvature, hyperbolic lobachevsky space, in presence of an external magnetic field, analogue of the homogeneous magnetic field in the minkowski space. a generalized formula for energy levels, describing quantization of the motion of the particle in magnetic field on the background of the lobachevsky space geometry, has been obtained.
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arxiv:1005.3487
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hard photon emitted from energetic heavy ion collisions is of very interesting since it does not experience the late - stage nuclear interaction, therefore it is useful to explore the early - stage information of matter phase. in this work, we have presented a first calculation of azimuthal asymmetry, characterized by directed transverse flow parameter $ f $ and elliptic asymmetry coefficient $ v _ 2 $, for proton - neutron bremsstrahlung hard photons in intermediate energy heavy - ion collisions. the positive $ f $ and negative $ v _ 2 $ of direct photons are illustrated and they seem to be anti - correlated to the corresponding free proton ' s flow.
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arxiv:0712.0299
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in this paper we address practical aspects of the implementation of the 0 - 1 test for chaos in deterministic systems. in addition, we present a new formulation of the test which significantly increases its sensitivity. the test can be viewed as a method to distill a binary quantity from the power spectrum. the implementation is guided by recent results from the theoretical justification of the test as well as by exploring better statistical methods to determine the binary quantities. we give several examples to illustrate the improvement.
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arxiv:0906.1418
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motivated by the matrix spencer conjecture, we study the problem of finding signed sums of matrices with a small matrix norm. a well - known strategy to obtain these signs is to prove, given matrices $ a _ 1, \ dots, a _ n \ in \ mathbb { r } ^ { m \ times m } $, a gaussian measure lower bound of $ 2 ^ { - o ( n ) } $ for a scaling of the discrepancy body $ \ { x \ in \ mathbb { r } ^ n : \ | \ sum _ { i = 1 } ^ n x _ i a _ i \ | \ leq 1 \ } $. we show this is equivalent to covering its polar with $ 2 ^ { o ( n ) } $ translates of the cube $ \ frac { 1 } { n } b ^ n _ \ infty $, and construct such a cover via mirror descent. as applications of our framework, we show : $ \ bullet $ matrix spencer for low - rank matrices. if the matrices satisfy $ \ | a _ i \ | _ { \ mathrm { op } } \ leq 1 $ and $ \ mathrm { rank } ( a _ i ) \ leq r $, we can efficiently find a coloring $ x \ in \ { \ pm 1 \ } ^ n $ with discrepancy $ \ | \ sum _ { i = 1 } ^ n x _ i a _ i \ | _ { \ mathrm { op } } \ lesssim \ sqrt { n \ log ( \ min ( rm / n, r ) ) } $. this improves upon the naive $ o ( \ sqrt { n \ log r } ) $ bound for random coloring and proves the matrix spencer conjecture when $ r m \ leq n $. $ \ bullet $ matrix spencer for block diagonal matrices. for block diagonal matrices with $ \ | a _ i \ | _ { \ mathrm { op } } \ leq 1 $ and block size $ h $, we can efficiently find a coloring $ x \ in \ { \ pm 1 \ } ^ n $ with $ \ | \ sum _ { i = 1 } ^ n x _ i a _ i \ | _ { \ mathrm { op } } \ lesssim \ sqrt { n \ log ( hm / n ) } $. using our proof, we reduce the matrix spencer conjecture to the existence of a $ o ( \ log (
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arxiv:2111.03171
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large multimodal models ( lmms ) have enabled new ai - powered applications that help people with visual impairments ( pvi ) receive natural language descriptions of their surroundings through audible text. we investigated how this emerging paradigm of visual assistance transforms how pvi perform and manage their daily tasks. moving beyond usability assessments, we examined both the capabilities and limitations of lmm - based tools in personal and social contexts, while exploring design implications for their future development. through interviews with 14 visually impaired users of be my ai ( an lmm - based application ) and analysis of its image descriptions from both study participants and social media platforms, we identified two key limitations. first, these systems ' context awareness suffers from hallucinations and misinterpretations of social contexts, styles, and human identities. second, their intent - oriented capabilities often fail to grasp and act on users ' intentions. based on these findings, we propose design strategies for improving both human - ai and ai - ai interactions, contributing to the development of more effective, interactive, and personalized assistive technologies.
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arxiv:2502.16098
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the nasa kepler mission has discovered thousands of new planetary candidates, many of which have been confirmed through follow - up observations. a primary goal of the mission is to determine the occurrance rate of terrestrial - size planets within the habitable zone ( hz ) of their host stars. here we provide a list of hz exoplanet candidates from the kepler data release 24 q1 - q17 data vetting process. this work was undertaken as part of the kepler habitable zone working group. we use a variety of criteria regarding hz boundaries and planetary sizes to produce complete lists of hz candidates, including a catalog of 104 candidates within the optimistic hz and 20 candidates with radii less than two earth radii within the conservative hz. we cross - match our hz candidates with the data release 25 stellar properties and confirmed planet properties to provide robust stellar parameters and candidate dispositions. we also include false positive probabilities recently calculated by morton et al. ( 2016 ) for each of the candidates within our catalogs to aid in their validation. finally, we performed dynamical analysis simulations for multi - planet systems that contain candidates with radii less than two earth radii as a step toward validation of those systems.
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arxiv:1608.00620
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visible - infrared person re - identification ( vi - reid ) plays a crucial role in applications such as search and rescue, infrastructure protection, and nighttime surveillance. however, it faces significant challenges due to modality discrepancies, varying illumination, and frequent occlusions. to overcome these obstacles, we propose \ textbf { aminet }, an adaptive modality interaction network. aminet employs multi - granularity feature extraction to capture comprehensive identity attributes from both full - body and upper - body images, improving robustness against occlusions and background clutter. the model integrates an interactive feature fusion strategy for deep intra - modal and cross - modal alignment, enhancing generalization and effectively bridging the rgb - ir modality gap. furthermore, aminet utilizes phase congruency for robust, illumination - invariant feature extraction and incorporates an adaptive multi - scale kernel mmd to align feature distributions across varying scales. extensive experiments on benchmark datasets demonstrate the effectiveness of our approach, achieving a rank - 1 accuracy of $ 74. 75 \ % $ on sysu - mm01, surpassing the baseline by $ 7. 93 \ % $ and outperforming the current state - of - the - art by $ 3. 95 \ % $.
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arxiv:2502.21163
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we establish a strong monogamy - of - entanglement property for subspace coset states, which are uniform superpositions of vectors in a linear subspace of $ \ mathbb { f } _ 2 ^ n $ to which has been applied a quantum one - time pad. this property was conjectured recently by [ coladangelo, liu, liu, and zhandry, crypto ' 21 ] and shown to have applications to unclonable decryption and copy - protection of pseudorandom functions. we present two proofs, one which directly follows the method of the original paper and the other which uses an observation from [ vidick and zhang, eurocrypt ' 20 ] to reduce the analysis to a simpler monogamy game based on bb ' 84 states. both proofs ultimately rely on the same proof technique, introduced in [ tomamichel, fehr, kaniewski and wehner, new journal of physics ' 13 ].
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arxiv:2107.13324
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we revisit a multi - spacecraft study of the element abundances of solar energetic particles ( seps ) in the 23 january 2012 event, where the power - law pattern of enhancements versus the mass - to - charge ratio a / q for the elements c through fe was partly disrupted by a break near mg, which turned out to be an unfortunate distraction. in the current article we find that extending that least - squares fits for c - fe down to h at a / q = 1 lends much more credence to the power laws, even though h itself was not included in the fits. we also investigate the extent of an adiabatically invariant " reservoir " of magnetically - trapped particles behind the shock wave in this event.
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arxiv:2004.12229
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kernel phase is a method to interpret stellar point source images by considering their formation as the analytical result of an interferometric process. using fourier formalism, this method allows for observing planetary companions around nearby stars at separations down to half a telescope resolution element, typically 20 \, mas for a 8 \, m class telescope in h band. the kernel - phase analysis has so far been mainly focused on working with a single monochromatic light image, recently providing theoretical contrast detection limits down to $ 10 ^ { - 4 } $ at 200 \, mas with jwst / niriss in the mid - infrared by using hypothesis testing theory. in this communication, we propose to extend this approach to data cubes provided by integral field spectrographs ( ifs ) on ground - based telescopes with adaptive optics to enhance the detection of planetary companions and explore the spectral characterization of their atmosphere by making use of the kernel - phase multi - spectral information. using ground - based ifs data cube with a spectral resolution r = 20, we explore different statistical tests based on kernel phases at three wavelengths to estimate the detection limits for planetary companions. our tests are first conducted with synthetic data before extending their use to real images from ground - based exoplanet imagers such as subaru / scexao and vlt / sphere in the near future. future applications to multi - wavelength data from space telescopes are also discussed for the observation of planetary companions with jwst.
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arxiv:2208.04594
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we consider a class of stochastic dynamical systems, called piecewise deterministic markov processes, with states $ ( x, \ s ) \ in \ o \ times \ g $, $ \ o $ being a region in $ \ bbr ^ d $ or the $ d $ - - dimensional torus, $ \ g $ being a finite set. the continuous variable $ x $ follows a piecewise deterministic dynamics, the discrete variable $ \ s $ evolves by a stochastic jump dynamics and the two resulting evolutions are fully - - coupled. we study stationarity, reversibility and time - - reversal symmetries of the process. increasing the frequency of the $ \ s $ - - jumps, we show that the system behaves asymptotically as deterministic and we investigate the structure of fluctuations ( i. e. deviations from the asymptotic behavior ), recovering in a non markovian frame results obtained by bertini et al. \ cite { bdgjl1, bdgjl2, bdgjl3, bdgjl4 }, in the context of markovian stochastic interacting particle systems. finally, we discuss a gallavotti - - cohen - - type symmetry relation with involution map different from time - - reversal. for several examples the above results are recovered by explicit computations.
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arxiv:0902.4195
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exploration of novel electromagnetic phenomena is a subject of great interest in topological quantum materials. one of the unprecedented effects to be experimentally verified is topological magnetoelectric ( tme ) effect originating from an unusual coupling of electric and magnetic fields in materials. a magnetic heterostructure of topological insulator ( ti ) hosts such an exotic magnetoelectric coupling and can be expected to realize the tme effect as an axion insulator. here we designed a magnetic ti with tricolor structure where a non - magnetic layer of ( bi, sb ) 2te3 is sandwiched by a soft ferromagnetic cr - doped ( bi, sb ) 2te3 and a hard ferromagnetic v - doped ( bi, sb ) 2te3. accompanied by the quantum anomalous hall ( qah ) effect, we observe zero hall conductivity plateaus, which are a hallmark of the axion insulator state, in a wide range of magnetic field between the coercive fields of cr - and v - doped layers. the resistance of the axion insulator state reaches as high as 10 ^ 9 ohm, leading to a gigantic magnetoresistance ratio exceeding 10, 000, 000 % upon the transition from the qah state. the tricolor structure of ti may not only be an ideal arena for the topologically distinct phenomena, but also provide magnetoresistive applications for advancing dissipationless topological electronics.
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arxiv:1708.05387
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we propose a parallel graph - based data clustering algorithm using cuda gpu, based on exact clustering of the minimum spanning tree in terms of a minimum isoperimetric criteria. we also provide a comparative performance analysis of our algorithm with other related ones which demonstrates the general superiority of this parallel algorithm over other competing algorithms in terms of accuracy and speed.
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arxiv:1702.04739
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we argue that, in order to obtain decoherence of spacetime, we should consider quantum conformal metric fluctuations of spacetime. this could be the required environment in the problem of selfmeasurement of spacetime in quantum gravity.
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arxiv:gr-qc/9704056
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we first extract the binding energy $ \ bar \ lambda $ and decay constants of the d wave heavy meson doublets $ ( 1 ^ { - }, 2 ^ { - } ) $ and $ ( 2 ^ { - }, 3 ^ { - } ) $ with qcd sum rule in the leading order of heavy quark effective theory. then we study their pionic $ ( \ pi, k, \ eta ) $ couplings using the light cone sum rule, from which the parameter $ \ bar \ lambda $ can also be extracted. we then calculate the pionic decay widths of the strange / non - strange d wave heavy $ d / b $ mesons and discuss the possible candidates for the d wave charm - strange mesons. further experimental information, such as the ratio between $ d _ s \ eta $ and $ dk $ modes, will be very useful to distinguish various assignments for $ d _ { sj } ( 2860, 2715 ) $.
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arxiv:hep-ph/0612066
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, abilities, and limitations when the procedures and products of technology are being designed. this field utilizes knowledge from several fields such as mechanical engineering, psychology, and industrial engineering to design instruments. human factors is broader than engineering psychology, which is focused specifically on designing systems that accommodate the information - processing capabilities of the brain. although the work in the respective fields differ, there are some similarities between these. these fields share the same objectives which are to optimize the effectiveness and efficiency with which human activities are conducted as well as to improve the general quality of life through increased safety, reduced fatigue and stress, increased comfort, and satisfaction. = = = importance of engineering psychologists = = = engineering psychologists contribute to the design of a variety of products, including dental and surgical tools, cameras, toothbrushes and car - seats. they have been involved in the re - design of the mailbags used by letter carriers. more than 20 % of letter carriers suffer from musculoskeletal injury such as lower back pain from carrying mailbags slung over their shoulders. a mailbag with a waist - support strap, and a double bag that requires the use of both shoulders, has been shown to reduce muscle fatigue. research by engineering psychologists has demonstrated that using cell - phones while driving degrades performance by increasing driver reaction time, particularly among older drivers, and can lead to higher accident risk among drivers of all ages. research findings such as these have supported governmental regulation of cell - phone use. = = references = = = = bibliography = = stanley n. roscoe ( 1997 ), the adolescence of engineering psychology, human factors and ergonomics society, archived from the original on 28 september 2011, retrieved 2 july 2011 francis durso, patricia delucia ( 2010 ), " engineering psychology ", the corsini encyclopedia of psychology, vol. 2, john wiley and sons, pp. 573 – 576, isbn 978 - 0 - 470 - 17026 - 7 wickens, christopher d. ; hollands, j. g. ( 2000 ), engineering psychology and human performance, prentice - hall, isbn 978 - 0 - 321 - 04711 - 3 journal of engineering psychology howell, william carl ( 1971 ). engineering psychology : current perspectives in research. new york : appleton - century - crofts. isbn 978 - 0 - 390 - 46456 - 9. wickens, christopher d. ( 1984 ). engineering psychology and human performance. columbus : merrill.
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https://en.wikipedia.org/wiki/Engineering_psychology
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repetitive counting ( repcount ) is critical in various applications, such as fitness tracking and rehabilitation. previous methods have relied on the estimation of red - green - and - blue ( rgb ) frames and body pose landmarks to identify the number of action repetitions, but these methods suffer from a number of issues, including the inability to stably handle changes in camera viewpoints, over - counting, under - counting, difficulty in distinguishing between sub - actions, inaccuracy in recognizing salient poses, etc. in this paper, based on the work done by [ 1 ], we integrate joint angles with body pose landmarks to address these challenges and achieve better results than the state - of - the - art repcount methods, with a mean absolute error ( mae ) of 0. 211 and an off - by - one ( obo ) counting accuracy of 0. 599 on the repcount data set [ 2 ]. comprehensive experimental results demonstrate the effectiveness and robustness of our method.
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arxiv:2308.08632
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this is a paper for a special issue of the journal " studia semiotyczne " devoted to stanislaw krajewski ' s paper [ 30 ]. this paper gives some supplementary notes to krajewski ' s [ 30 ] on the anti - mechanist arguments based on g \ " { o } del ' s incompleteness theorem. in section 3, we give some additional explanations to section 4 - 6 in krajewski ' s [ 30 ] and classify some misunderstandings of g \ " { o } del ' s incompleteness theorem related to anti - mechanist arguments. in section 4 and 5, we give a more detailed discussion of g \ " { o } del ' s disjunctive thesis, g \ " { o } del ' s undemonstrability of consistency thesis and the definability of natural numbers as in section 7 - 8 in krajewski ' s [ 30 ], describing how recent advances bear on these issues.
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arxiv:1902.05902
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we propose a novel active learning framework capable to train effectively a convolutional neural network for semantic segmentation of medical imaging, with a limited amount of training labeled data. our contribution is a practical cost - effective active learning approach using dropout at test time as monte carlo sampling to model the pixel - wise uncertainty and to analyze the image information to improve the training performance. the source code of this project is available at https : / / marc - gorriz. github. io / ceal - medical - image - segmentation /.
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arxiv:1711.09168
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recent studies reveal that a double - quantum - dot system hosting more than two electrons may be superior in certain aspects as compared to the traditional case in which only two electrons are confined ( a singlet - triplet qubit ). we study the electron - phonon dephasing occurring in a gaas multi - electron double - quantum - dot system, in a biased case in which the singlet state is hybridized, as well as in an unbiased case in which the hybridization is absent. we have found that while the electron - phonon dephasing rate increases with the number of electrons confined in the unbiased case, this does not hold in the biased case. we define a merit figure as a ratio between the exchange energy and the dephasing rate, and have shown that in experimentally relevant range of the exchange energy, the merit figure actually increases with the number of electrons in the biased case. our results show that the multi - electron quantum - dot system has another advantage in mitigating the effect of electron - phonon dephasing, which is previously under - appreciated in the literature.
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arxiv:2203.16138
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recent angle resolved photoemission data, which found evidence for a d - wave - like modulation of the antiferromagnetic gap, suggest an intimate interrelation between the antiferromagnetic insulator and the superconductor with its d - wave gap. it is shown here that a projected so ( 5 ) theory, which explicitly takes the mott - hubbard gap into account, correctly describes the observed gap characteristics. specifically, it accounts for the order of magnitude difference between the antiferromagnetic gap modulation and the superconducting gap and is also consistent with the gap dispersion.
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arxiv:cond-mat/9912161
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a simple approach to gyro and accelerometer bias estimation is proposed. it does not involve kalman filtering or similar formal techniques. instead, it is based on physical intuition and exploits a duality between gimbaled and strapdown inertial systems. the estimation problem is decoupled into two separate stages. at the first stage, inertial system attitude errors are corrected by means of a feedback from an external aid. in the presence of uncompensated biases, the steady - state feedback rebalances those biases and can be used to estimate them. at the second stage, the desired bias estimates are expressed in a closed form in terms of the feedback signal. the estimator has only three tunable parameters and is easy to implement and use. the tests proved the feasibility of the proposed approach for the estimation of low - cost mems inertial sensor biases on a moving land vehicle.
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arxiv:1212.0892
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let $ [ n ] = \ { 1, \ ldots, n \ } $ be the $ n $ - chain. we give presentations for the following transformation semigroups : the semigroup of full order - decreasing mappings of $ [ n ] $, the semigroup of partial one - to - one order - decreasing mappings of $ [ n ] $, the semigroup of full order - preserving and order - decreasing mappings of $ [ n ] $, the semigroup of partial one - to - one order - preserving and order - decreasing mappings of $ [ n ] $, and the semigroup of partial order - preserving and order - decreasing mappings of $ [ n ] $.
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arxiv:1702.02788
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the status of qcd phenomena and open problems are reviewed
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arxiv:hep-ph/0306287
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we study analytically and numerically the magnetotransport of strained graphene in a corbino geometry gating in the presence of an external perpendicular magnetic field. the conductance of the corbino disc of deformed graphene with a uniaxial and an inhomogeneous strain is calculated by using the landauer - b \ " { u } ttiker method. we show that the oscillation period of the conductance as a function of the magnetic flux depends on uniaxial strain and the conductance sharply drops along the direction of graphene stretching. the conductance amplitude, on the other hand, can be manipulated by induced pseudomagnetic flux. a valley polarized regime, caused by the inhomogeneous strain, is obtained and in addition we find a wide energy interval in which the system is fully valley polarized.
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arxiv:1309.0307
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the giant arcs in the clusters of galaxies are modeled in the framework of the superbubbles. the density of the intracluster medium is assumed to follow a hyperbolic behavior. the analytical law of motion is function of the elapsed time and the polar angle. as a consequence the flux of kinetic energy in the expanding thin layer decreases with increasing polar angle making the giant arc invisible to the astronomical observations. in order to calibrate the arcsec - parsec conversion three cosmologies are analyzed.
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arxiv:1904.04029
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we report a systematic enhancement of the pressure dependence of tn in a2 + [ v2 ] o4 spinels as the v - v separation approaches the critical separation for a transition to itinerant - electron behavior. an intermediate phase between localized and itinerant electron behavior is identified in zn [ v2 ] o4 and mg [ v2 ] o4 exhibiting mobile holes as large polarons. in zn [ v2 ] o4, cooperative ordering of v - v pairs below a ts = tn does not totally suppress the v3 + - ion spins at ambient pressure, but makes tn to decrease with pressure. our results demonstrate that zn [ v2 ] o4 and mg [ v2 ] o4 are less localized than previously thought.
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arxiv:0706.1468
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^ { ( 1 ) } \ neq u _ { \ infty } ^ { ( 2 ) } \ in h _ { 0 } ^ { 2 } ( \ omega ) $ are two nontrivial solutions of dirichlet bvps on the bounded domain $ \ omega $. it is worth noting that the regularity of weak solutions $ u _ { \ infty } ^ { ( i ) } ( i = 1, 2 ) $ here is explored. finally, the nonexistence of nontrivial solutions is also obtained for $ a $ large enough.
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arxiv:1812.03043
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we investigate the connections between patterns in permutations and forbidden configurations in restricted elections, first discovered by lackner and lackner, in order to enhance the approach initiated by the two mentioned authors. more specifically, our achievements are essentially two. first, we define a new type of domain restriction, called enriched group - separable. enriched group - separable elections are a subset of group - separable elections, which describe a special, still natural, situation that can arise in the context of group - separability. the exact enumeration of group - separable elections has been very recently determined by karpov. here we give a recursive characterization for enriched group - separable elections, from which we are able to find a recurrence relation and a closed formula expressing their number. our second achievement is a generalization of a result of lackner and lackner, concerning the connection between permutation patterns and forbidden configurations with 3 voters. our result relates forbidden configurations with the strong order on pairs of permutations, a notion which is still largely undeveloped, and suggests a potential approach for the determination of upper bounds for restricted elections whose forbidden configurations contains at least one configuration with 3 voters.
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arxiv:1906.10553
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we present an updated measurement of time - dependent cp - violating asymmetries in neutral b decays with the babar detector at the pep - ii asymmetric b factory at slac. this result uses an additional sample of upsilon ( 4s ) decays collected in 2001, bringing the data available to 32 million b - anti - b pairs. we select events in which one neutral b meson is fully reconstructed in a final state containing charmonium and the flavor of the other neutral b meson is determined from its decay products. the amplitude of the cp - violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. the result sin2beta = 0. 59 + / - 0. 14 ( stat ) + / - 0. 05 ( syst ) establishes cp violation in the b ^ 0 meson system. we also determine | lambda | = 0. 93 + / - 0. 09 { stat } + / - 0. 03 { syst }, consistent with no direct cp violation.
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arxiv:hep-ex/0107013
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interpretability allows the domain - expert to directly evaluate the model ' s relevance and reliability, a practice that offers assurance and builds trust. in the healthcare setting, interpretable models should implicate relevant biological mechanisms independent of technical factors like data pre - processing. we define personalized interpretability as a measure of sample - specific feature attribution, and view it as a minimum requirement for a precision health model to justify its conclusions. some health data, especially those generated by high - throughput sequencing experiments, have nuances that compromise precision health models and their interpretation. these data are compositional, meaning that each feature is conditionally dependent on all other features. we propose the deep compositional data analysis ( deepcoda ) framework to extend precision health modelling to high - dimensional compositional data, and to provide personalized interpretability through patient - specific weights. our architecture maintains state - of - the - art performance across 25 real - world data sets, all while producing interpretations that are both personalized and fully coherent for compositional data.
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arxiv:2006.01392
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the flow - induced flutter has a significant role in aircraft stability, renewable energy extraction, animal locomotion, among many other applications. while being a ubiquitous phenomenon, the control of the flutter response has been primarily limited to simplified systems and, often, with the help of linear inviscid flow theories. in this paper, we numerically investigate how the plunging response of a foil can be regulated using an active flap to improve structural safety or enhance the energy extraction efficiency of the foil with a tightly coupled fluid - structure interaction algorithm. a broad range of foil and flap settings was tested and their flow dynamics have been investigated. a novel multi - scale modal analysis technique suitable for fluid - structure interaction systems successfully isolates the active flap - induced and the flow - induced modes. it is observed that the competition between these two modes dictates the plunging response of the foil. the active flap can modulate the leading edge vortex shedding with larger flapping amplitude and regulate the foil heaving motion. the ratio of the competing modal energy is proposed to evaluate the control efficacy of the morphing surface, and the onset of the lock - in is associated with the ratio approaching unity. it is shown that the morphing flap is a good candidate for active flow control.
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arxiv:2201.09957
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let $ p $ be a prime. we show that if a pro - $ p $ group with at most 2 defining relations has quadratic $ \ mathbb { f } _ p $ - cohomology, then such algebra is universally koszul. this proves the " universal koszulity conjecture " formulated by j. min \ ' a \ v { c } et al. in the case of maximal pro - $ p $ galois groups of fields with at most 2 defining relations.
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arxiv:2003.09186
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we define and study kinematical observables involving fermion spin, such as the total spin of a collection of particles, in loop quantum gravity. due to the requirement of gauge invariance, the relevant quantum states contain strong entanglement between gravity and fermionic degrees of freedom. interestingly we find that properties and spectra of the observables are nevertheless similar to their counterparts from quantum mechanics. however, there are also new effects. due to the entanglement between gravity and fermionic degrees of freedom, alignment of quantum spins has consequences for quantized geometry. we sketch a particular effect of this kind that may in principle be observable.
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arxiv:2011.00233
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we present an algorithm that exploits quantum parallelism to simulate randomness in a quantum system. in our scheme, all possible realizations of the random parameters are encoded quantum mechanically in a superposition state of an auxiliary system. we show how our algorithm allows for the efficient simulation of dynamics of quantum random spin chains with known numerical methods. we also propose an experimental realization based on atoms in optical lattices in which disorder could be simulated in parallel and in a controlled way through the interaction with another atomic species.
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arxiv:cond-mat/0505288
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we introduce a variational quantum solver for combinatorial optimizations over $ m = \ mathcal { o } ( n ^ k ) $ binary variables using only $ n $ qubits, with tunable $ k > 1 $. the number of parameters and circuit depth display mild linear and sublinear scalings in $ m $, respectively. moreover, we analytically prove that the specific qubit - efficient encoding brings in a super - polynomial mitigation of barren plateaus as a built - in feature. this leads to unprecedented quantum - solver performances. for $ m = 7000 $, numerical simulations produce solutions competitive in quality with state - of - the - art classical solvers. in turn, for $ m = 2000 $, an experiment with $ n = 17 $ trapped - ion qubits featured maxcut approximation ratios estimated to be beyond the hardness threshold $ 0. 941 $. to our knowledge, this is the highest quality attained experimentally on such sizes. our findings offer a novel heuristics for quantum - inspired solvers as well as a promising route towards solving commercially - relevant problems on near term quantum devices.
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arxiv:2401.09421
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in this paper, we give new characterizations of modular riesz bases in hilbert $ c ^ * $ - modules. we prove that modular riesz bases share many properties with riesz bases in hilbert spaces. moreover we show that there are also important differences ; for example, there exist exact frames that are not modular riesz bases.
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arxiv:1910.07243
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retrieval - augmented generation ( rag ) has emerged as a way to complement the in - context knowledge of large language models ( llms ) by integrating external documents. however, real - world applications demand not only accuracy but also interpretability. while dense retrieval methods provide high accuracy, they lack interpretability ; conversely, sparse retrieval methods offer transparency but often fail to capture the full intent of queries due to their reliance on keyword matching. to address these issues, we introduce iterkey, an llm - driven iterative keyword generation framework that enhances rag via sparse retrieval. iterkey consists of three llm - driven stages : generating keywords for retrieval, generating answers based on retrieved documents, and validating the answers. if validation fails, the process iteratively repeats with refined keywords. across four qa tasks, experimental results show that iterkey achieves 5 % to 20 % accuracy improvements over bm25 - based rag and simple baselines. its performance is comparable to dense retrieval - based rag and prior iterative query refinement methods using dense models. in summary, iterkey is a novel bm25 - based approach leveraging llms to iteratively refine rag, effectively balancing accuracy with interpretability.
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arxiv:2505.08450
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in this article we consider hook removal operators on odd partitions, i. e., partitions labelling odd - degree irreducible characters of finite symmetric groups. in particular we complete the discussion, started by isaacs, navarro, olsson and tiep in 2016, concerning the commutativity of such operators.
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arxiv:1711.08908
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we systematically studied in - plane optical conductivity of fese $ _ { 1 - x } $ te $ _ { x } $ thin films fabricated on caf $ _ { 2 } $ substrates for $ x $ = 0, 0. 1, 0. 2, and 0. 4. this system shows a large enhancement of superconducting transition temperature $ t _ { \ mathrm { c } } $ at $ x \ sim $ 0. 2 and a gentle decrease in $ t _ { \ mathrm { c } } $ with further increasing $ x $. the low - energy optical conductivity spectrum is described by the sum of narrow and broad drude components, associated with coherent and incoherent charge dynamics, respectively. with increasing te content, the spectral weight of the narrow drude component decreases, while the total weight of the two drude components increases. as a consequence, the fraction of the narrow drude weight significantly decreases, indicating that te substitution leads to stronger electronic correlations. below the nematic transition temperature, the narrow drude weight decreases with decreasing temperature. this indicates the reduction of the coherent carrier density, resulting from the fermi - surface modification induced by the development of the orbital order. the reduction of the narrow drude weight with temperature stopped at $ x \ sim $ 0. 2, corresponding to the disappearance of the nematic transition. our result suggests that the increase in the coherent carrier density induced by the suppression of the nematic transition gives rise to the enhancement of $ t _ { \ mathrm { c } } $. the decrease in $ t _ { \ mathrm { c } } $ with further te substitution likely arises from too strong electronic correlations, which are not favorable for superconductivity.
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arxiv:2103.13659
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we introduce a new method to evaluate algebraic integrals over the simplex numerically. this new approach employs techniques from tropical geometry and exceeds the capabilities of existing numerical methods by an order of magnitude. the method can be improved further by exploiting the geometric structure of the underlying integrand. as an illustration of this, we give a specialized integration algorithm for a class of integrands that exhibit the form of a generalized permutahedron. this class includes integrands for scattering amplitudes and parametric feynman integrals with tame kinematics. a proof - of - concept implementation is provided with which feynman integrals up to loop order 17 can be evaluated.
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arxiv:2008.12310
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this paper investigates the distributed continuous - time nonconvex optimization problem over unbalanced directed networks. the objective is to cooperatively drive all the agent states to an optimal solution that minimizes the sum of the local cost functions. based on the topology balancing technique and adaptive control approach, a novel fully distributed algorithm is developed for each agent with neither prior global information concerning network connectivity nor convexity of local cost functions. by viewing the proposed algorithm as a perturbed system, its input - to - state stability with a vanishing perturbation is first established, and asymptotic convergence of the decision variables toward the optimal solution is then proved under the relaxed condition. a key feature of the algorithm design is that it removes the dependence on the smallest strong convexity constant of local cost functions, and the left eigenvector corresponding to the zero eigenvalue of the laplacian matrix of unbalanced directed topologies. the effectiveness of the proposed fully distributed algorithm is illustrated with two examples.
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arxiv:2211.16977
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this study provides the first comprehensive assessment of consistency and reproducibility in large language model ( llm ) outputs in finance and accounting research. we evaluate how consistently llms produce outputs given identical inputs through extensive experimentation with 50 independent runs across five common tasks : classification, sentiment analysis, summarization, text generation, and prediction. using three openai models ( gpt - 3. 5 - turbo, gpt - 4o - mini, and gpt - 4o ), we generate over 3. 4 million outputs from diverse financial source texts and data, covering md & as, fomc statements, finance news articles, earnings call transcripts, and financial statements. our findings reveal substantial but task - dependent consistency, with binary classification and sentiment analysis achieving near - perfect reproducibility, while complex tasks show greater variability. more advanced models do not consistently demonstrate better consistency and reproducibility, with task - specific patterns emerging. llms significantly outperform expert human annotators in consistency and maintain high agreement even where human experts significantly disagree. we further find that simple aggregation strategies across 3 - 5 runs dramatically improve consistency. we also find that aggregation may come with an additional benefit of improved accuracy for sentiment analysis when using newer models. simulation analysis reveals that despite measurable inconsistency in llm outputs, downstream statistical inferences remain remarkably robust. these findings address concerns about what we term " g - hacking, " the selective reporting of favorable outcomes from multiple generative ai runs, by demonstrating that such risks are relatively low for finance and accounting tasks.
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arxiv:2503.16974
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gait analysis using computer vision is an emerging field in ai, offering clinicians an objective, multi - feature approach to analyse complex movements. despite its promise, current applications using rgb video data alone are limited in measuring clinically relevant spatial and temporal kinematics and establishing normative parameters essential for identifying movement abnormalities within a gait cycle. this paper presents a data - driven method using rgb video data and 2d human pose estimation for developing normative kinematic gait parameters. by analysing joint angles, an established kinematic measure in biomechanics and clinical practice, we aim to enhance gait analysis capabilities and improve explainability. our cycle - wise kinematic analysis enables clinicians to simultaneously measure and compare multiple joint angles, assessing individuals against a normative population using just monocular rgb video. this approach expands clinical capacity, supports objective decision - making, and automates the identification of specific spatial and temporal deviations and abnormalities within the gait cycle.
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arxiv:2411.13716
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are of no value and may be harmful. adaptive instructional materials tailor questions to each student ' s ability and calculate their scores, but this encourages students to work individually rather than socially or collaboratively ( kruse, 2013 ). social relationships are important, but high - tech environments may compromise the balance of trust, care, and respect between teacher and student. massively open online courses ( moocs ), although quite popular in discussions of technology and education in developed countries ( more so in the us ), are not a major concern in most developing or low - income countries. one of the stated goals of moocs is to provide less fortunate populations ( i. e., in developing countries ) an opportunity to experience courses with us - style content and structure. however, research shows only 3 % of the registrants are from low - income countries, and although many courses have thousands of registered students only 5 – 10 % of them complete the course. this can be attributed to lack of staff support, course difficulty, and low levels of engagement with peers. moocs also implies that certain curriculum and teaching methods are superior, and this could eventually wash over ( or possibly washing out ) local educational institutions, cultural norms, and educational traditions. with the internet and social media, using educational apps makes students highly susceptible to distraction and sidetracking. even though proper use has been shown to increase student performance, being distracted would be detrimental. another disadvantage is an increased potential for cheating. a disadvantage of e - learning is that it can cause depression, according to a study made during the 2021 covid - 19 quarantines. = = = over - stimulation = = = electronic devices such as cell phones and computers facilitate rapid access to a stream of sources, each of which may receive cursory attention. michel rich, an associate professor at harvard medical school and executive director of the center on media and child health in boston, said of the digital generation, " their brains are rewarded not for staying on task, but for jumping to the next thing. the worry is we ' re raising a generation of kids in front of screens whose brains are going to be wired differently. " students have always faced distractions ; computers and cell phones are a particular challenge because the stream of data can interfere with focusing and learning. although these technologies affect adults too, young people may be more influenced by it as their developing brains can easily become habituated to switching tasks and become unaccustomed to sustaining attention. too much information, coming too rapidly,
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https://en.wikipedia.org/wiki/Educational_technology
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we construct fundamental solutions of second - order parabolic systems of divergence form with bounded and measurable leading coefficients and divergence free first - order coefficients in the class of $ bmo ^ { - 1 } _ x $, under the assumption that weak solutions of the system satisfy a certain local boundedness estimate. we also establish gaussian upper bound for such fundamental solutions under the same conditions.
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arxiv:1707.09162
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we study the limiting behavior of the $ k $ - th eigenvalue $ x _ k $ of unitary invariant ensembles with freud - type and uniform convex potentials. as both $ k $ and $ n - k $ tend to infinity, we obtain gaussian fluctuations for $ x _ k $ in the bulk and soft edge cases, respectively. multi - dimensional central limit theorems, as well as moderate deviations, are also proved. this work generalizes earlier results in the gue and unitary invariant ensembles with monomial potentials of even degree. in particular, we obtain the precise asymptotics of corresponding christoffel - darboux kernels as well.
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arxiv:1409.4008
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in this short note, we hope to give a rapid induction for non - experts into the world of differential harnack inequalities, which have been so influential in geometric analysis and probability theory over the past few decades. at the coarsest level, these are often mysterious - looking inequalities that hold for ` positive ' solutions of some parabolic pde, and can be verified quickly by grinding out a computation and applying a maximum principle. in this note we emphasise the geometry behind the harnack inequalities, which typically turn out to be assertions of the convexity of some natural object. as an application, we explain how hamilton ' s differential harnack inequality for mean curvature flow of a $ n $ - dimensional submanifold of $ r ^ { n + 1 } $ can be viewed as following directly from the well - known preservation of convexity under mean curvature flow, but this time of a $ ( n + 1 ) $ - dimensional submanifold of $ r ^ { n + 2 } $. we also briefly survey the earlier work that led us to these observations.
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arxiv:1301.1543
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we report experimental test - beam results on dielectric - loaded waveguide detectors that utilize microwave cherenkov signals to time and characterize high energy particle showers. these results are used to validate models and produce high - fidelity simulations of timing plane systems which yield picosecond time tags and millimeter spatial coordinates for the shower centroid. these timing planes, based on the askaryan effect in solid dielectrics, are most effective at the high center - of - momentum energies planned for the future circular collider ( fcc - hh ), and are of particular interest in the forward region due to their high radiation immunity. we use our beam test results and geant4 simulations to validate a hybrid microwave detector model, which is used to simulate a reference timing plane design for the fcc forward calorimeters. our results indicate that 0. 5 - 3 ps particle timing is possible for a wide range of collision products in the reference fcc hadron collider detector, even with current technology.
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arxiv:2112.00936
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in the simpson moduli space $ m $ of semi - stable sheaves with hilbert polynomial $ dm - 1 $ on a projective plane we study the closed subvariety $ m ' $ of sheaves that are not locally free on their support. we show that for $ d \ ge 4 $ it is a singular subvariety of codimension $ 2 $ in $ m $. the blow up of $ m $ along $ m ' $ is interpreted as a ( partial ) modification of $ m \ setminus m ' $ by vector bundles ( on support ).
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arxiv:1511.01847
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we propose an inexact variable - metric proximal point algorithm to accelerate gradient - based optimization algorithms. the proposed scheme, called qning can be notably applied to incremental first - order methods such as the stochastic variance - reduced gradient descent algorithm ( svrg ) and other randomized incremental optimization algorithms. qning is also compatible with composite objectives, meaning that it has the ability to provide exactly sparse solutions when the objective involves a sparsity - inducing regularization. when combined with limited - memory bfgs rules, qning is particularly effective to solve high - dimensional optimization problems, while enjoying a worst - case linear convergence rate for strongly convex problems. we present experimental results where qning gives significant improvements over competing methods for training machine learning methods on large samples and in high dimensions.
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arxiv:1610.00960
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we propose a generalization of the minkowski average of two subsets of a riemannian manifold, in which geodesics are replaced by an arbitrary family of parametrized curves. under certain assumptions, we characterize families of curves on a riemannian surface for which a brunn - minkowski inequality holds with respect to a given volume form. in particular, we prove that under these assumptions, a family of constant - speed curves on a riemannian surface satisfies the brunn - minkowski inequality with respect to the riemannian area form if and only if the geodesic curvature of its members is determined by a function $ \ kappa $ on the surface, and $ \ kappa $ satisfies the inequality $ $ k + \ kappa ^ 2 - | \ nabla \ kappa | \ ge 0 $ $ where $ k $ is the gauss curvature.
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arxiv:2211.04585
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we analyze effects due to transverse degrees of freedom in qcd calculations of the fundamental hard exclusive amplitude of $ \ gamma ^ * \ gamma \ to \ pi ^ 0 $ transition. a detailed discussion is given of the relation between the modified factorization approach ( mfa ) of sterman et al. and standard factorization ( sfa ). working in feynman gauge, we construct basic building blocks of mfa from the one - loop coefficient function of the sfa, demonstrating that sudakov effects are distinctly different from higher - twist corrections. we show also that the handbag - type diagram, contrary to naive expectations, does not contain an infinite chain of $ ( m ^ 2 / q ^ 2 ) ^ n $ corrections : they come only from diagrams with transverse gluons emitted from the hard propagator. a simpler picture emerges within the qcd sum rule approach : the sum over soft $ \ bar q g... g q $ fock components is dual to $ \ bar qq $ states generated by the local axial current. we combine the results based on qcd sum rules with pqcd radiative corrections and observe that the gap between our curves for the asymptotic and cz distribution amplitudes is sufficiently large for an experimental discrimination between them.
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arxiv:hep-ph/9702443
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the purpose of this paper is to review the concept of cryptocurrencies in our economy. first, bitcoin and alternative cryptocurrencies ' histories are analyzed. we then study the implementation of bitcoin in the airline and real estate industries. our study finds that many bitcoin companies partner with airlines in order to decrease processing times, to provide ease of access for spending in international airports, and to reduce fees on foreign exchanges for fuel expenses, maintenance, and flight operations. bitcoin transactions have occurred in the real estate industry, but many businesses are concerned with bitcoin ' s potential interference with the u. s. government and its high volatility. as bitcoin ' s price has been growing rapidly, we assessed bitcoin ' s real value ; bitcoin derives value from its scarcity, utility, and public trust. in the conclusion, we discuss bitcoin ' s future and conclude that bitcoin may change from a short - term profit investment to a more steady industry as we identify bitcoin with the " greater fool theory ", and as the number of available bitcoins to be mined dwindles and technology becomes more expensive.
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arxiv:2010.01337
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using school choice as a motivating example, we introduce a stylized model of a many - to - one matching market where the clearinghouse aims to implement contingent priorities, i. e., priorities that depend on the current assignment, to prioritize students with siblings and match them together. we provide a series of guidelines and introduce two natural approaches to implement them : ( i ) absolute, whereby a prioritized student can displace any student without siblings assigned to the school, and ( ii ) partial, whereby prioritized students can only displace students that have a less favorable lottery than their priority provider. we study several properties of the corresponding mechanisms, including the existence of a stable assignment under contingent priorities, the complexity of deciding whether there exists one, and its incentive properties. furthermore, we introduce a soft version of these priorities to guarantee existence, and we provide mathematical programming formulations to find such stable matching or certify that one does not exist. finally, using data from the chilean school choice system, we show that our framework can significantly increase the number of students assigned to their top preference and the number of siblings assigned together relative to current practice.
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arxiv:2409.04914
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we present the status of the unitarity triangle analysis focused on the analyses connected to the ckm angles extraction. the angle values are found to be $ \ alpha = ( 90. 6 \ pm 6. 6 ) ^ { \ circ } $, $ \ sin ( 2 \ beta ) = 0. 68 \ pm 0. 023 $, and $ \ gamma = ( 72. 2 \ pm 9. 2 ) ^ { \ circ } $.
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arxiv:1301.3300
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using the spectral functions measured in $ \ tau $ decays, we investigate the actual numerical impact of duality violations on the extraction of the strong coupling. these effects are tiny in the standard $ \ alpha _ s ( m _ \ tau ^ 2 ) $ determinations from integrated distributions of the hadronic spectrum with pinched weights, or from the total $ \ tau $ hadronic width. the pinched - weight factors suppress very efficiently the violations of duality, making their numerical effects negligible in comparison with the larger perturbative uncertainties. however, combined fits of $ \ alpha _ s $ and duality - violation parameters, performed with non - protected weights, are subject to large systematic errors associated with the assumed modelling of duality - violation effects. these uncertainties have not been taken into account in the published analyses, based on specific models of quark - hadron duality.
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arxiv:2205.07587
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this paper has been withdrawn by the author, since one of the key results duplicates existing work, as pointed out by a reader. i am currently revising the manuscript.
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arxiv:cond-mat/0011409
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animal re - identification ( reid ) has become an indispensable tool in ecological research, playing a critical role in tracking population dynamics, analyzing behavioral patterns, and assessing ecological impacts, all of which are vital for informed conservation strategies. unlike human reid, animal reid faces significant challenges due to the high variability in animal poses, diverse environmental conditions, and the inability to directly apply pre - trained models to animal data, making the identification process across species more complex. this work introduces an innovative keypoint propagation mechanism, which utilizes a single annotated image and a pre - trained diffusion model to propagate keypoints across an entire dataset, significantly reducing the cost of manual annotation. additionally, we enhance the vision transformer ( vit ) by implementing keypoint positional encoding ( kpe ) and categorical keypoint positional embedding ( ckpe ), enabling the vit to learn more robust and semantically - aware representations. this provides more comprehensive and detailed keypoint representations, leading to more accurate and efficient re - identification. our extensive experimental evaluations demonstrate that this approach significantly outperforms existing state - of - the - art methods across four wildlife datasets. the code will be publicly released.
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arxiv:2412.00818
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prediction sets have recently been shown to be a promising strategy for quantifying the uncertainty of deep neural networks in a way that provides theoretical guarantees. however, existing techniques have largely targeted settings where the space of labels is simple, so prediction sets can be arbitrary subsets of labels. for structured prediction problems where the space of labels is exponential in size, even prediction sets containing a small fraction of all labels can be exponentially large. in the context of code generation, we propose a solution that considers a restricted set of prediction sets that can compactly be represented as partial programs, which are programs with portions replaced with holes. given a trained code generation model, our algorithm leverages a programming language ' s abstract syntax tree to generate a set of programs such that the correct program is in the set with high - confidence. valuable applications of our algorithm include a codex - style code generator with holes in uncertain parts of the generated code, which provides a partial program with theoretical guarantees. we evaluate our approach on picard ( a t5 model for sql semantic parsing ) and codex ( a gpt model for over a dozen programming languages, including python ), demonstrating that our approach generates compact pac prediction sets. this is the first research contribution that generates pac prediction sets for generative code models.
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arxiv:2302.08703
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in this paper we develop the basic homotopy theory of g - symmetric spectra ( that is, symmetric spectra with a g - action ) for a finite group g, as a model for equivariant stable homotopy with respect to a g - set universe. this model lies in between mandell ' s equivariant symmetric spectra and the g - orthogonal spectra of mandell and may and is quillen equivalent to the two. we further discuss equivariant semistability, construct model structures on module, algebra and commutative algebra categories and describe the homotopical properties of the multiplicative norm in this context.
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arxiv:1411.2290
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in this paper, we present ur - air system submission to the logical access ( la ) and the speech deepfake ( df ) tracks of the asvspoof 2021 challenge. the la and df tasks focus on synthetic speech detection ( ssd ), i. e. detecting text - to - speech and voice conversion as spoofing attacks. different from previous asvspoof challenges, the la task this year presents codec and transmission channel variability, while the new task df presents general audio compression. built upon our previous research work on improving the robustness of the ssd systems to channel effects, we propose a channel - robust synthetic speech detection system for the challenge. to mitigate the channel variability issue, we use an acoustic simulator to apply transmission codec, compression codec, and convolutional impulse responses to augmenting the original datasets. for the neural network backbone, we propose to use emphasized channel attention, propagation and aggregation time delay neural networks ( ecapa - tdnn ) as our primary model. we also incorporate one - class learning with channel - robust training strategies to further learn a channel - invariant speech representation. our submission achieved eer 20. 33 % in the df task ; eer 5. 46 % and min - tdcf 0. 3094 in the la task.
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arxiv:2107.12018
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surface tension tends to minimize the area of interfaces between pieces of matter in different thermodynamic phases, be they in the solid or the liquid state. this can be relevant for the macroscopic shape of very soft solids, and lead to a roughening of initially sharp edges. we calculate this effect for a neo - hookean elastic solid, with assumptions corresponding to actual experiments, namely the case where an initially sharp edge is rounded by the effect of surface tension felt when the fluid surrounding the soft solid ( and so surface tension ) is changed at the solid / liquid boundary. we consider two opposite limits where the analysis can be carried to the end, the one of a shallow angle and the one of a very sharp angle. both cases yield a discontinuity of curvature in the state with surface tension although the initial state had a discontinuous slope.
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arxiv:1408.2266
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we present an algorithm that fully reverses the shoebox image source method ( ism ), a popular and widely used room impulse response ( rir ) simulator for cuboid rooms introduced by allen and berkley in 1979. more precisely, given a discrete multichannel rir generated by the shoebox ism for a microphone array of known geometry, the algorithm reliably recovers the 18 input parameters. these are the 3d source position, the 3 dimensions of the room, the 6 - degrees - of - freedom room translation and orientation, and an absorption coefficient for each of the 6 room boundaries. the approach builds on a recently proposed gridless image source localization technique combined with new procedures for room axes recovery and first - order - reflection identification. extensive simulated experiments reveal that near - exact recovery of all parameters is achieved for a 32 - element, 8. 4 - cm - wide spherical microphone array and a sampling rate of 16 ~ khz using fully randomized input parameters within rooms of size 2x2x2 to 10x10x5 meters. estimation errors decay towards zero when increasing the array size and sampling rate. the method is also shown to strongly outperform a known baseline, and its ability to extrapolate rirs at new positions is demonstrated. crucially, the approach is strictly limited to low - passed discrete rirs simulated using the vanilla shoebox ism. nonetheless, it represents to our knowledge the first algorithmic demonstration that this difficult inverse problem is in - principle fully solvable over a wide range of configurations.
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arxiv:2405.03385
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using complete - count register data spanning three generations, we compare inter - and multigenerational transmission processes across municipalities in sweden. we first document spatial patterns in intergenerational ( parent - child ) mobility, and study whether those patterns are robust to the choice of mobility statistic and the quality of the underlying microdata. we then ask whether there exists similar geographic variation in multigenerational mobility. interpreting those patterns through the lens of a latent factor model, we identify which features of the transmission process vary across places.
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arxiv:2504.10721
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instrumental variables ( ivs ) are widely used to study the causal effect of an exposure on an outcome in the presence of unmeasured confounding. ivs require an instrument, a variable that is ( a1 ) associated with the exposure, ( a2 ) has no direct effect on the outcome except through the exposure, and ( a3 ) is not related to unmeasured confounders. unfortunately, finding variables that satisfy conditions ( a2 ) or ( a3 ) can be challenging in practice. this paper reviews works where instruments may not satisfy conditions ( a2 ) or ( a3 ), which we refer to as invalid instruments. we review identification and inference under different violations of ( a2 ) or ( a3 ), specifically under linear models, non - linear models, and heteroskedatic models. we conclude with an empirical comparison of various methods by re - analyzing the effect of body mass index on systolic blood pressure from the uk biobank.
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arxiv:2407.19558
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this paper is concerned with the density - suppressed motility model : $ u _ { t } = \ delta ( \ displaystyle \ frac { u ^ m } { v ^ \ alpha } ) + \ beta uf ( w ), v _ { t } = d \ delta v - v + u, w _ { t } = \ delta w - uf ( w ) $ in a smoothly bounded convex domain $ \ omega \ subset { \ mathbb { r } } ^ 2 $, where $ m > 1 $, $ \ alpha > 0, \ beta > 0 $ and $ d > 0 $ are parameters, the response function $ f $ satisfies $ f \ in c ^ 1 ( [ 0, \ infty ) ), f ( 0 ) = 0, f ( w ) > 0 $ in $ ( 0, \ infty ) $. this system describes the density - suppressed motility of eeshcrichia coli cells in process of spatio - temporal pattern formation via so - called self - trapping mechanisms. based on the duality argument, it is shown that for suitable large $ d $ the problem admits at least one global weak solution $ ( u, v, w ) $ which will asymptotically converge to the spatially uniform equilibrium $ ( \ overline { u _ 0 } + \ beta \ overline { w _ 0 }, \ overline { u _ 0 } + \ beta \ overline { w _ 0 }, 0 ) $ with $ \ overline { u _ 0 } = \ frac1 { | \ omega | } \ int _ { \ omega } u ( x, 0 ) dx $ and $ \ overline { w _ 0 } = \ frac1 { | \ omega | } \ int _ { \ omega } w ( x, 0 ) dx $ in $ l ^ \ infty ( \ omega ) $.
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arxiv:2103.00420
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extreme - ultraviolet and x - ray jets occur frequently in magnetically open coronal holes on the sun, especially at high solar latitudes. some of these jets are observed by white - light coronagraphs as they propagate through the outer corona toward the inner heliosphere, and it has been proposed that they give rise to microstreams and torsional alfv \ ' { e } n waves detected in situ in the solar wind. to predict and understand the signatures of coronal - hole jets, we have performed a detailed statistical analysis of such a jet simulated with an adaptively refined magnetohydrodynamics model. the results confirm the generation and persistence of three - dimensional, reconnectiondriven magnetic turbulence in the simulation. we calculate the spatial correlations of magnetic fluctuations within the jet and find that they agree best with the m \ " { u } ller - biskamp scaling model including intermittent current sheets of various sizes coupled via hydrodynamic turbulent cascade. the anisotropy of the magnetic fluctuations and the spatial orientation of the current sheets are consistent with an ensemble of nonlinear alfv \ ' { e } n waves. these properties also reflect the overall collimated jet structure imposed by the geometry of the reconnecting magnetic field. a comparison with ulysses observations shows that turbulence in the jet wake is in quantitative agreement with that in the fast solar wind.
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arxiv:1607.03843
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we describe the design and 3d sensing performance of an omnidirectional stereo - vision system ( omnistereo ) as applied to micro aerial vehicles ( mavs ). the proposed omnistereo model employs a monocular camera that is co - axially aligned with a pair of hyperboloidal mirrors ( folded catadioptric configuration ). we show that this arrangement is practical for performing stereo - vision when mounted on top of propeller - based mavs characterized by low payloads. the theoretical single viewpoint ( svp ) constraint helps us derive analytical solutions for the sensor ' s projective geometry and generate svp - compliant panoramic images to compute 3d information from stereo correspondences ( in a truly synchronous fashion ). we perform an extensive analysis on various system characteristics such as its size, catadioptric spatial resolution, field - of - view. in addition, we pose a probabilistic model for uncertainty estimation of the depth from triangulation for skew back - projection rays. we expect to motivate the reproducibility of our solution since it can be adapted ( optimally ) to other catadioptric - based omnistereo vision applications.
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arxiv:1510.00771
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emotions are the intrinsic or extrinsic representations of our experiences. the importance of emotions during a human - human interaction is immense as it formulates the basis of our interaction framework. there are several approaches in psychology to evaluate emotional states in humans based on the perceived stimuli. however, the topic has been less explored as far as human - robot interaction is concerned. this paper uses an appropriate emotion appraisal mechanism from psychology, generating an emotional state in a humanoid robot on - the - fly during human - robot interaction. since the exhibition of only six basic emotions is not sufficient to cater to diverse situations, the use of the circumplex model in this work has allowed the life - sized robot called robin to experience 28 emotional states in different interaction scenarios. realistic robot behaviour has been generated based on the proposed appraisal system in various interaction scenarios.
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arxiv:2202.09813
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clinical diagnosis of the eye is performed over multifarious data modalities including scalar clinical labels, vectorized biomarkers, two - dimensional fundus images, and three - dimensional optical coherence tomography ( oct ) scans. clinical practitioners use all available data modalities for diagnosing and treating eye diseases like diabetic retinopathy ( dr ) or diabetic macular edema ( dme ). enabling usage of machine learning algorithms within the ophthalmic medical domain requires research into the relationships and interactions between all relevant data over a treatment period. existing datasets are limited in that they neither provide data nor consider the explicit relationship modeling between the data modalities. in this paper, we introduce the ophthalmic labels for investigating visual eye semantics ( olives ) dataset that addresses the above limitation. this is the first oct and near - ir fundus dataset that includes clinical labels, biomarker labels, disease labels, and time - series patient treatment information from associated clinical trials. the dataset consists of 1268 near - ir fundus images each with at least 49 oct scans, and 16 biomarkers, along with 4 clinical labels and a disease diagnosis of dr or dme. in total, there are 96 eyes ' data averaged over a period of at least two years with each eye treated for an average of 66 weeks and 7 injections. we benchmark the utility of olives dataset for ophthalmic data as well as provide benchmarks and concrete research directions for core and emerging machine learning paradigms within medical image analysis.
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arxiv:2209.11195
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social scientists have long appreciated that relationships between individuals cannot be described from observing a single domain, and that the structure across domains of interaction can have important effects on outcomes of interest ( e. g., cooperation ). 1 one debate explicitly about this surrounds food sharing. some argue that failing to find reciprocal food sharing means that some process other than reciprocity must be occurring, whereas others argue for models that allow reciprocity to span domains in the form of trade. 2 multilayer networks, high - dimensional networks that allow us to consider multiple sets of relationships at the same time, are ubiquitous and have consequences, so processes giving rise to them are important social phenomena. the analysis of multi - dimensional social networks has recently garnered the attention of the network science community. 3 recent models of these processes show how ignoring layer interdependencies can lead one to miss why a layer formed the way it did, and / or draw erroneous conclusions. 6 understanding the structuring processes that underlie multiplex networks will help understand increasingly rich datasets, giving more accurate and complete pictures of social interactions.
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arxiv:1903.11183
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we derive a class of non - static inhomogeneous dust solutions in f ( r ) gravity described by the lemaitre - tolman - bondi ( ltb ) metric. the field equations are fully integrated for all parameter subcases and compared with analogous subcases of ltb dust solutions of gr. since the solutions do not admit regular symmetry centres, we have two possibilities : ( i ) a spherical dust cloud with angle deficit acting as the source of a vacuum schwarzschild - like solution associated with a global monopole, or ( ii ) fully regular dust wormholes without angle deficit, whose rest frames are homeomorphic to the schwarzschild - kruskal manifold or to a 3d torus. the compatibility between the ltb metric and generic f ( r ) ansatzes furnishes an " inverse procedure " to generate ltb solutions whose sources are found from the f ( r ) geometry. while the resulting fluids may have an elusive physical interpretation, they can be used as exact non - - perturbative toy models in theoretical and cosmological applications of f ( r ) theories.
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arxiv:1707.00191
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let $ g $ and $ h $ be real - valued arithmetic functions, positive and normalized. specific choices within the following general scheme of recursively defined polynomials \ begin { equation * } p _ n ^ { g, h } ( x ) : = \ frac { x } { h ( n ) } \ sum _ { k = 1 } ^ { n } g ( k ) \, p _ { n - k } ^ { g, h } ( x ), \ end { equation * } with initial value $ p _ { 0 } ^ { g, h } ( x ) = 1 $ encode information about several classical, widely studied polynomials. this includes chebyshev polynomials of the second kind, associated laguerre polynomials, and the nekrasov - - okounkov polynomials. in this paper we prove that for $ g ( n ) = n $ and fixed $ h $ we obtain orthogonal polynomial sequences for positive definite functionals. let $ h ( n ) = n ^ s $ with $ 0 \ leq s \ leq 1 $. then the sequence satisfies tur \ ' an inequalities for $ x \ geq 0 $.
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arxiv:2204.01008
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a model for the coherent output coupler of the bose - einstein condensed atoms from a trap in the recent mit experiment ( phys. rev. lett., 78 ( 1997 ) 582 ) is established with a simple many - boson system of two states with linear coupling. its exact solution for the many - body problem shows a factorization of dynamical evolution process, i. e., the wave function initially prepared in a direct product of a vacuum state and a coherent state remains in a direct product of two coherent states at any instance in the evolution of the total system. this conclusion always holds even for a system with a finite average particle number in the initial state. its thermodynamical limit can be directly dealt with in the bogoliubov approximation and manifests that an ideal condensate in the trap will remain in a coherent state after the r. f. interaction while the output - coupler pulse of atoms is also in a coherent state, which means a coherent output of atomic beam to form a macroscopic quantum state in a propagating mode.
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arxiv:quant-ph/9706041
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in this paper, we consider for any free presentation $ g = f / r $ of a group $ g $ the coinvariance $ h _ { 0 } ( g, r _ { ab } ^ { \ otimes n } ) $ of the $ n $ - th tensor power of the relation module $ r _ { ab } $ and show that the homology group $ h _ { 2n } ( g, { \ mathbb z } ) $ may be identified with the limit of the groups $ h _ { 0 } ( g, r _ { ab } ^ { \ otimes n } ) $, where the limit is taken over the category of these presentations of $ g $. we also consider the free lie ring generated by the relation module $ r _ { ab } $, in order to relate the limit of the groups $ \ gamma _ { n } r / [ \ gamma _ { n } r, f ] $ to the $ n $ - torsion subgroup of $ h _ { 2n } ( g, { \ mathbb z } ) $.
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arxiv:0812.2092
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##umber \ end { align }
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arxiv:1503.03156
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we try to understand the recently observed anomalous behavior of the photon - to - pion transition form factor in the holographic qcd approach. first the holographic description of the anomalous \ gamma ^ * \ gamma ^ * \ pi ^ 0 form factor is reviewed and applied to various models. it is illustrated that in describing the anomalous form factor, the holographic approach is asymptotically dual to the perturbative qcd ( pqcd ) framework, with the pion mode \ pi ( z ) \ sim z corresponding to the asymptotic pion distribution amplitude. this indicates some inconsistency in light - front holography, since \ pi ( z ) \ sim z would be dual to \ varphi ( x ) \ sim \ sqrt { x ( 1 - x ) } there. after clarifying these subtleties, we employ the relation between the holographic and the perturbative expressions to study possible asymptotic violation of the transition form factor. it is found that if one require that the asymptotic form factor possess a pqcd - like expression, the pion mode can only be ultraviolet - enhanced by logarithmic factors. the minimally deformed pion mode will then be of the form \ pi ( z ) \ sim z \ ln ( z \ lambda ) ^ { - 1 }. we suppose that this deformation may be due to the coupling of the pion with a nontrivial open string tachyon field, and then the parameter $ \ lambda $ will be related to the quark condensate. interestingly, this pion mode leads immediately to radyushkin ' s logarithmic model, which fitted very well the experimental data in the large - q ^ 2 region. on the other side, the pqcd interpretation with a flat - like pion distribution amplitude, proposed by radyushkin and polyakov, fails to possess a holographic expression.
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arxiv:1105.6008
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a state - of - the - art method that combines a quantum computational algorithm and machine learning, so - called quantum machine learning, can be a powerful approach for solving quantum many - body problems. however, the research scope in the field was mainly limited to organic molecules and simple lattice models. here, we propose a workflow of quantum machine learning applications for periodic systems on the basis of an effective model construction from first principles. the band structures of the hubbard model of graphene with the mean - field approximation are calculated as a benchmark, and the calculated eigenvalues show good agreement with the exact diagonalization results within a few mev by employing the transfer learning technique in quantum machine learning. the results show that the present computational scheme has the potential to solve many - body problems quickly and correctly for periodic systems using a quantum computer.
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arxiv:1911.10330
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let $ s _ { g, p } $ denote the genus $ g $ orientable surface with $ p $ punctures. we show that nested train track sequences constitute $ o ( ( g, p ) ^ { 2 } ) $ - quasiconvex subsets of the curve graph, effectivizing a theorem of masur and minsky. as a consequence, the genus $ g $ disk set is $ o ( g ^ { 2 } ) $ - quasiconvex. we also show that splitting and sliding sequences of birecurrent train tracks project to $ o ( ( g, p ) ^ { 2 } ) $ - unparameterized quasi - geodesics in the curve graph of any essential subsurface, an effective version of a theorem of masur, mosher, and schleimer.
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arxiv:1306.1428
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this study was aimed to consider the ng - group that consisting of transformations on a nonempty set a has no bijection as its element. in addition, it tried to find the maximal order of these groups. it found the order of ng - group not greater than n. our results proved by showing that any kind of ng - group in the theorem be isomorphic to a permutation group on a quotient set of a with respect to an equivalence relation on a.
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arxiv:2105.11973
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we propose a family of spectral gradient methods, whose stepsize is determined by a convex combination of the long barzilai - borwein ( bb ) stepsize and the short bb stepsize. each member of the family is shown to share certain quasi - newton property in the sense of least squares. the family also includes some other gradient methods as its special cases. we prove that the family of methods is $ r $ - superlinearly convergent for two - dimensional strictly convex quadratics. moreover, the family is $ r $ - linearly convergent in the any - dimensional case. numerical results of the family with different settings are presented, which demonstrate that the proposed family is promising.
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arxiv:1812.02974
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the potential energy loss of aging buildings traps building owners in a cycle of underfunding operations and overpaying maintenance costs. energy auditors intending to generate an energy model of a target building for performance assessment may struggle to obtain accurate results as the spatial distribution of temperatures is not considered when calculating the u - value of the building envelope. this paper proposes a pixel - level method based on infrared thermography ( irt ) that considers two - dimensional ( 2d ) spatial temperature distributions of the outdoor and indoor surfaces of the target wall to generate a 2d u - value map of the wall. the result supports that the proposed method can better reflect the actual thermal insulation performance of the target wall compared to the current irt - based methods that use a single - point room temperature as input.
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arxiv:2401.07163
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we study the effects of strong $ 1 / r $ long - range coulomb interactions in a weyl semimetal. we consider a three - dimensional ( 3d ) dirac fermion system on a lattice with a time - reversal symmetry breaking term, and take into account $ 1 / r $ long - range coulomb interactions between the bulk electrons. this model is regarded as the case where magnetic impurities are doped into the bulk of a 3d topological insulator. with the use of the strong coupling expansion of the lattice gauge theory and the mean - field approximation, we analyze the system from the strong coupling limit. it is shown that parity symmetry of the system is spontaneously broken in the strong coupling limit, and a different type of the weyl semimetal, in which time - reversal and parity symmetries are broken, appears in the strong coupling limit. a possible global phase diagram of a correlated weyl semimetal is presented.
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arxiv:1309.1079
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lhcb has collected the world ' s largest sample of charmed hadrons. this sample is used to measure the mixing parameters in the $ d ^ 0 $ - $ \ bar { d } ^ 0 $ system and to search for indirect $ cp $ violation. this contribution focuses on measurements of $ a _ { \ gamma } $ with $ d ^ * $ and semileptonic $ b $ decays and on mixing measurements and a search for $ cp $ violation in $ d \ to k \ pi $ decays.
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arxiv:1508.04975
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we obtain a class of anisotropic spherically symmetric relativistic solutions of compact objects in hydrostatic equilibrium in the $ f ( r, t ) = r + 2 \ chi t $ modified gravity, where $ r $ is the ricci scalar, $ t $ is the trace of the energy momentum tensor and $ \ chi $ is a dimensionless coupling parameter. the matter lagrangian is $ l _ { m } = - \ frac { 1 } { 3 } ( 2p _ { t } + p _ { r } ) $, where $ p _ r $ and $ p _ t $ represents the radial and tangential pressures. compact objects with dense nuclear matter is expected to be anisotropic. stellar models are constructed for anisotropic neutron stars working in the modified finch - skea ( fs ) ansatz without preassuming an equation of state. the stellar models are investigate plotting physical quantities like energy density, anisotropy parameter, radial and tangential pressures in all particular cases. the stability of stellar models are checked using the causality conditions and adiabatic index. using the observed mass of a compact star we obtain stellar models that predicts the radius of the star and eos for matter inside the compact objects with different values of gravitational coupling constant $ \ chi $. it is also found that a more massive star can be accommodated with $ \ chi < 0 $. the stellar models obtained here obey the physical acceptability criteria which show consistency for a class of stable compact objects in modified $ f ( r, t ) $ gravity.
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arxiv:2009.08277
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in this study, we explore the correlation functions of thin - shell operators, represented semiclassically by a homogeneous, thin interface of dust particles. employing the monodromy method, we successfully compute the contribution from the virasoro vacuum block and present the monodromy equation in a closed form without assuming the probe limit. although an analytical solution to the monodromy equation remains difficult, we demonstrate that it is perturbatively solvable within specific limits, including the probe, the heavy - shell, and the early - time limits. moreover, we compare our results with gravitational calculations and find precise agreement. we strengthen our findings by proving that the thermal correlation functions in gravity, after an inverse laplace transformation, satisfy the field theory ' s monodromy equation. additionally, we identify an infinite series of unphysical solutions to the monodromy equation and discuss their potential geometrical duals.
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arxiv:2404.11423
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in this report, an analytic model to predict phase transitions of confined fluids in nano systems is presented and it is used to predict the behavior of the confined fluid in nanotubes and nanoslits. in our approach besides including a third degree of freedom due to wall effect to define the state of the system, the tensorial character for pressure is considered. using the perturbation theory of statistical mechanics it is shown that the van der waals equation of state is equally valid for small as well as large systems. the model proposed is shown to predict the liquid - vapor phase transition as well as the critical point in any size confined fluid systems. it is also shown that the critical temperature increases with the size of the nano system and finally it reaches the macroscopic critical temperature value as the diameter of the nanotube ( or width of the nanoslit ) approaches infinity. the proposed model can also demonstrate the existence of the local density and phase fragmentations during phase transitions in a confined nano system.
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arxiv:1803.11499
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the moral foundations theory supports that people, across cultures, tend to consider a small number of dimensions when classifying issues on a moral basis. the data also show that the statistics of weights attributed to each moral dimension is related to self - declared political affiliation, which in turn has been connected to cognitive learning styles by recent literature in neuroscience and psychology. inspired by these data, we propose a simple statistical mechanics model with interacting neural networks classifying vectors and learning from members of their social neighborhood about their average opinion on a large set of issues. the purpose of learning is to reduce dissension among agents even when disagreeing. we consider a family of learning algorithms parametrized by \ delta, that represents the importance given to corroborating ( same sign ) opinions. we define an order parameter that quantifies the diversity of opinions in a group with homogeneous learning style. using monte carlo simulations and a mean field approximation we find the relation between the order parameter and the learning parameter \ delta at a temperature we associate with the importance of social influence in a given group. in concordance with data, groups that rely more strongly on corroborating evidence sustains less opinion diversity. we discuss predictions of the model and propose possible experimental tests.
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arxiv:1307.3203
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adjustment in early elementary school age " in which they declare how the positive or negative effects of mobile technology depend entirely on its context and use. the authors offer studies that illustrate that even where there is positive development of cognitive and academic skills via increased technological time, there are much more negative effects on a child ' s social and psychological development which can include anything from reduced face to face interaction for children to affecting a child ' s sleep and behavior. in family life, this technological invention has caused positive and negative effects of equal measure. while others may view this gadget as having eased communication among people and families, some researchers have proved otherwise. these gadgets have strengthened family units. for example, families compensate for daily stress through text messages, phone calls, and e - mails. internet - enabled phones have also assisted in the connection through social sites where family members can discuss their issues even if they are far apart ( alamenciak, 2012 ). in america, for instance, parents have adjusted to modern technology thus increasing their connection with their children who may be working in different states. cell phones are bringing families together as they increase the quality of communication among the family members are living separately in the distance. families use cell phones to get in touch with their children by the use of e - mails and web ( george, 2008 ). these families contact their children to know how they ' re redoing and entertain them in the process. moreover, cell phone communication brings families more closely increasing the relationship between family members. during this time, family heads promote values and set good examples to their children. they encourage openness and communication in case problems arise in the family as well as security since family members get the opportunity to know each other well. also, cell phones have enhanced accountability either in working premises or at homes. people keep in touch with their core - workers and employees as well as their family members ( good connection, bad example : cell phones and the family, 2007 ). = = future of smartphones = = the next generation of smartphones will be context - aware, taking advantage of the growing availability of embedded physical sensors and data exchange abilities. one of the main features applying to this is that phones will start keeping track of users ' personal data, and adapt to anticipate the information will need. all - new applications will come out with the new phones, one of which is an x - ray device that reveals information about any location at which the phone is pointed. companies are developing software to take advantage of more accurate location - sensing
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https://en.wikipedia.org/wiki/Mobile_technology
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the scaling properties of the cluster size distribution of a system of diffusing clusters is studied in terms of a simple kinetic mean field model. it is shown that a one parameter family of mathematically valid scaling solutions exists. despite this, the kinetics reaches a unique scaling solution independent of initial conditions. this selected scaling solution is marginally physical ; i. e., it is the borderline solution between the unphysical and physical branches of the family of solutions.
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arxiv:cond-mat/9804150
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low - mass cluster galaxies are the most common galaxy type in the universe and are at a cornerstone of our understanding of galaxy formation, cluster luminosity functions, dark matter and the formation of large scale structure. i describe in this summary recent observational results concerning the properties and likely origins of low - mass galaxies in clusters and the implications of these findings in broader galaxy formation issues.
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arxiv:astro-ph/0212219
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in the study of trapped two - component bose gases, a widely used dynamical protocol is to start from the ground state of a one - component condensate and then switch half the atoms into another hyperfine state. the slightly different intra - component and inter - component interactions can then lead to highly nontrivial dynamics. we study and classify the possible subsequent dynamics, over a wide variety of parameters spanned by the trap strength and by the inter - to intra - component interaction ratio. a stability analysis suited to the trapped situation provides us with a framework to explain the various types of dynamics in different regimes.
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arxiv:1210.0030
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