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driven by the visions of data science, recent years have seen a paradigm shift in natural language processing ( nlp ). nlp has set the milestone in text processing and proved to be the preferred choice for researchers in the healthcare domain. the objective of this paper is to identify the potential of nlp, especially, how nlp is used to support the knowledge management process in the healthcare domain, making data a critical and trusted component in improving the health outcomes. this paper provides a comprehensive survey of the state - of - the - art nlp research with a particular focus on how knowledge is created, captured, shared, and applied in the healthcare domain. our findings suggest, first, the techniques of nlp those supporting knowledge management extraction and knowledge capture processes in healthcare. second, we propose a conceptual model for the knowledge extraction process through nlp. finally, we discuss a set of issues, challenges, and proposed future research areas.
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arxiv:2007.09134
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function dom : mor ( c ) → ob ( c ), a codomain or target class function cod : mor ( c ) → ob ( c ), for every three objects a, b and c, a binary operation hom ( a, b ) × hom ( b, c ) → hom ( a, c ) called composition of morphisms. here hom ( a, b ) denotes the subclass of morphisms f in mor ( c ) such that dom ( f ) = a and cod ( f ) = b. morphisms in this subclass are written f : a → b, and the composite of f : a → b and g : b → c is often written as g ∘ f or gf. such that the following axioms hold : the associative law : if f : a → b, g : b → c and h : c → d then h ∘ ( g ∘ f ) = ( h ∘ g ) ∘ f, and the ( left and right unit laws ) : for every object x, there exists a morphism 1x : x → x ( some authors write idx ) called the identity morphism for x, such that every morphism f : a → x satisfies 1x ∘ f = f, and every morphism g : x → b satisfies g ∘ 1x = g. we write f : a → b, and we say " f is a morphism from a to b ". we write hom ( a, b ) ( or homc ( a, b ) when there may be confusion about to which category hom ( a, b ) refers ) to denote the hom - class of all morphisms from a to b. some authors write the composite of morphisms in " diagrammatic order ", writing f ; g or fg instead of g ∘ f. from these axioms, one can prove that there is exactly one identity morphism for every object. often the map assigning each object its identity morphism is treated as an extra part of the structure of a category, namely a class function i : ob ( c ) → mor ( c ). some authors use a slight variant of the definition in which each object is identified with the corresponding identity morphism. this stems from the idea that the fundamental data of categories are morphisms and not objects. in fact, categories can be defined without reference to objects at all
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https://en.wikipedia.org/wiki/Category_(mathematics)
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an iterative coupling algorithm based on restricted additive schwarz domain decomposition is investigated to co - simulate electrical circuits with hybrid electromagnetic ( emt ) and transient stability ( ts ) modeled using dynamic phasors. this co - simulation algorithm does not introduce any delay between the data exchanged at the co - simulation step. the pure linear convergence property of the iterative method allows it to be accelerated towards the true solution by a non - intrusive aitken ' s acceleration of the convergence post - processing, even if the domain decomposition interface conditions make the iterative method divergent. this provides a method less sensitive to the splitting. numerical tests on a linear rlc circuit combining emt and ts modeling are provided.
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arxiv:2212.05232
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we study the instability of a reissner - nordstr \ " om - ads ( rnads ) black hole under perturbations of a massive scalar field coupled to einstein tensor. calculating the potential of the scalar perturbations we find that as the strength of the coupling of the scalar to einstein tensor is increasing, the potential develops a negative well outside the black hole horizon, indicating an instability of the background rnads. we then investigate the effect of this coupling on the quasinormal modes. we find that there exists a critical value of the coupling which triggers the instability of the rnads. we also find that as the charge of the rnads is increased towards its extremal value, the critical value of the derivative coupling is decreased.
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arxiv:1903.10850
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uniformly finite homology is a coarse homology theory, defined via chains that satisfy a uniform boundedness condition. by construction, uniformly finite homology carries a canonical $ \ ell ^ \ infty $ - semi - norm. we show that, for uniformly discrete spaces of bounded geometry, this semi - norm on uniformly finite homology in degree 0 with integral coefficients allows for a new formulation of whyte ' s rigidity result. in contrast, we prove that this semi - norm is trivial on uniformly finite homology in higher degrees with real coefficients.
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arxiv:1502.01177
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topic classification systems on spoken documents usually consist of two modules : an automatic speech recognition ( asr ) module to convert speech into text and a text topic classification ( ttc ) module to predict the topic class from the decoded text. in this paper, instead of using the asr transcripts, the fusion of deep acoustic and linguistic features is used for topic classification on spoken documents. more specifically, a conventional ctc - based acoustic model ( am ) using phonemes as output units is first trained, and the outputs of the layer before the linear phoneme classifier in the trained am are used as the deep acoustic features of spoken documents. furthermore, these deep acoustic features are fed to a phoneme - to - word ( p2w ) module to obtain deep linguistic features. finally, a local multi - head attention module is proposed to fuse these two types of deep features for topic classification. experiments conducted on a subset selected from switchboard corpus show that our proposed framework outperforms the conventional asr + ttc systems and achieves a 3. 13 % improvement in acc.
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arxiv:2106.08637
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we study the effect of squark - generation mixing on gluino decays in the minimal supersymmetric standard model ( mssm ). we show that due to the effect the quark - flavor violating ( qfv ) gluino decay branching ratio b ( gluino - > c bar { t } ( t bar { c } ) + neutralino _ 1 ) can be very large ( up to ~ 50 % ) in a significant part of the mssm parameter space despite the very strong experimental constraints on qfv from b meson observables. this could have an important impact on the search for gluinos and the determination of the mssm parameters at lhc.
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arxiv:1005.0547
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encapsulated bulk mode microresonators in the megahertz range are used in commercial timekeeping and sensing applications but their performance is limited by the current state of the art of readout methods. we demonstrate a readout using dispersive coupling between a high - q encapsulated bulk mode micromechanical resonator and a lumped element microwave resonator that is implemented with commercially available components and standard printed circuit board fabrication methods and operates at room temperature and pressure. a frequency domain measurement of the microwave readout system yields a displacement resolution of $ 522 \, \ mathrm { fm / \ sqrt { hz } } $, which demonstrates an improvement over the state of the art of displacement measurement in bulk - mode encapsulated microresonators. this approach can be readily implemented in cryogenic measurements, allowing for future work characterizing the thermomechanical noise of encapsulated bulk mode resonators at cryogenic temperatures.
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arxiv:2207.08343
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most fake news detection ( fnd ) methods often struggle with data scarcity for emerging news domain. recently, prompt learning based on pre - trained language models ( plm ) has emerged as a promising approach in domain adaptive few - shot learning, since it greatly reduces the need for labeled data by bridging the gap between pre - training and downstream task. furthermore, external knowledge is also helpful in verifying emerging news, as emerging news often involves timely knowledge that may not be contained in the plm ' s outdated prior knowledge. to this end, we propose cool, a comprehensive knowledge enhanced prompt learning method for domain adaptive few - shot fnd. specifically, we propose a comprehensive knowledge extraction module to extract both structured and unstructured knowledge that are positively or negatively correlated with news from external sources, and adopt an adversarial contrastive enhanced hybrid prompt learning strategy to model the domain - invariant news - knowledge interaction pattern for fnd. experimental results demonstrate the superiority of cool over various state - of - the - arts.
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arxiv:2406.10870
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the formalism of subdynamics is extended to the functional approach of quantum systems, and used for the friedrichs model, in which diagonal singularities in states and observables are included. we compute in this approach the generalized eigenvectors and eigenvalues of the liouvulle - von newmann operator, using an iterative scheme. as complex generalized eigenvalues are obtained, the decay rates of unstable modes are included in the spectral decomposition.
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arxiv:quant-ph/9903079
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we show that the canonical formulation of a generic action for 1 + 1 - dimensional models of gravity coupled to matter admits a description in terms of ashtekar - type variables. this includes the cghs model and spherically symmetric reductions of 3 + 1 gravity as particular cases. this opens the possibility of discussing models of black hole evaporation using loop representation techniques and verifying which paradigm emerges for the possible elimination of the black hole singularity and the issue of information loss.
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arxiv:0909.0459
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we consider the variational approach to prove the existence of solutions of second order stationary mean field games on a bounded domain $ \ omega \ subseteq \ mathbb { r } ^ { d } $, with neumann boundary conditions, and with and without density constraints. we consider hamiltonians which growth as $ | \ cdot | ^ { q ' } $, where $ q ' = q / ( q - 1 ) $ and $ q > d $. despite this restriction, our approach allows us to prove the existence of solutions in the case of rather general coupling terms. when density constraints are taken into account, our results improve those in \ cite { messil }. furthermore, our approach can be used to obtain solutions of systems with multiple populations.
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arxiv:1704.02125
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quantum batteries, composed of quantum cells, are expected to outperform their classical analogs. the origin of such advantages lies in the role of quantum correlations, which may arise during the charging and discharging processes performed on the battery. in this theoretical work, we introduce a systematic characterization of the relevant quantities of quantum batteries, i. e., the capacity and the power, in relation to such correlations. for these quantities, we derive upper bounds for batteries that are a collection of noninteracting quantum cells with fixed hamiltonians. the capacity, that is, a bound on the stored or extractable energy, is derived with the help of the energy - entropy diagram, and this bound is respected as long as the charging and discharging processes are entropy preserving. while studying power, we consider a geometric approach for the evolution of the battery state in the energy eigenspace of the battery hamiltonian. then, an upper bound for power is derived for arbitrary charging process, in terms of the fisher information and the energy variance of the battery. the former quantifies the speed of evolution, and the latter encodes the nonlocal character of the battery state. indeed, due to the fact that the energy variance is bounded by the multipartite entanglement properties of batteries composed of qubits, we establish a fundamental bound on power imposed by quantum entanglement. we also discuss paradigmatic models for batteries that saturate the bounds both for the stored energy and power. several experimentally realizable quantum batteries, based on integrable spin chains, the lipkin - meshkov - glick and the dicke models, are also studied in the light of these newly introduced bounds.
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arxiv:1811.04005
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the problem of burning of high - velocity gas streams in channels is revisited. previous treatments of this issue are found to be incomplete. it is shown that despite relative smallness of the transversal gas velocity, it plays crucial role in determining flame structure. in particular, it is necessary in formulating boundary conditions near the flame anchor, and for the proper account of the flame propagation law. using the on - shell description of steady anchored flames, a consistent solution of the problem is given. equations for the flame front position and gas - velocity at the front are obtained. it is demonstrated that they reduce to a second - order differential equation for the front position. numerical solutions of the derived equations are found.
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arxiv:0902.4379
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this paper studies the $ n $ - particle systems as well as the hjb / master equations for a class of generalized mean field control ( mfc ) problems and the corresponding potential mean field games of control ( mfgc ). a local in time classical solution for the hjb equation is generated via a probabilistic approach based on the mean field maximum principle. given an extension of the so called displacement convexity condition, we obtain the uniform estimates on the hjb equation for the $ n $ - particle system. such estimates imply the displacement convexity / semi - concavity and thus the prior estimates on the solution to the hjb equation for generalized mfc problems. the global well - posedness of hjb / master equation for generalized mfc / potential mfgc is then proved thanks to the local well - posedness and the prior estimates. in view of the nature of the displacement convexity condition, such well - posedness is also true for the degenerated case. our analysis on the $ n $ - particle system also induces an lipschitz approximator to the optimal feedback function in generalized mfc / potential mfgc where an algebraic convergence rate is obtained. furthermore, an alternative approximate nash equilibrium is proposed based on the $ n $ - particle system, where the approximation error is quantified thanks to the aforementioned uniform estimates.
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arxiv:2412.11742
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a key challenge towards the goal of multi - part assembly tasks is finding robust sensorimotor control methods in the presence of uncertainty. in contrast to previous works that rely on a priori knowledge on whether two parts match, we aim to learn this through physical interaction. we propose a hierarchical approach that enables a robot to autonomously assemble parts while being uncertain about part types and positions. in particular, our probabilistic approach learns a set of differentiable filters that leverage the tactile sensorimotor trace from failed assembly attempts to update its belief about part position and type. this enables a robot to overcome assembly failure. we demonstrate the effectiveness of our approach on a set of object fitting tasks. the experimental results indicate that our proposed approach achieves higher precision in object position and type estimation, and accomplishes object fitting tasks faster than baselines.
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arxiv:2101.02725
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the sum of the first $ n \ geq 1 $ eigenvalues of the laplacian is shown to be maximal among triangles for the equilateral triangle, maximal among parallelograms for the square, and maximal among ellipses for the disk, provided the ratio $ \ text { ( area ) } ^ 3 / \ text { ( moment of inertia ) } $ for the domain is fixed. this result holds for both dirichlet and neumann eigenvalues, and similar conclusions are derived for robin boundary conditions and schr \ " odinger eigenvalues of potentials that grow at infinity. a key ingredient in the method is the tight frame property of the roots of unity. for general convex plane domains, the disk is conjectured to maximize sums of neumann eigenvalues.
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arxiv:1009.5326
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at first we give a little formalism to show some features of spontaneous cp violation theory. then we give a convincing argument show that cronin etc ' s experiment is a evidence of cpt violation and spontaneous cp violation is absolutely necessary. final we discuss some possible cpt violation mechanism.
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arxiv:1104.5319
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in this paper we study a subordinate brownian motion with a gaussian component and a rather general discontinuous part. the assumption on the subordinator is that its laplace exponent is a complete bernstein function with a l \ ' evy density satisfying a certain growth condition near zero. the main result is a boundary harnack principle with explicit boundary decay rate for non - negative harmonic functions of the process in $ c ^ { 1, 1 } $ open sets. as a consequence of the boundary harnack principle, we establish sharp two - sided estimates on the green function of the subordinate brownian motion in any bounded $ c ^ { 1, 1 } $ open set $ d $ and identify the martin boundary of $ d $ with respect to the subordinate brownian motion with the euclidean boundary.
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arxiv:1106.5858
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in the setting of the classical cramer - lundberg risk insurance model, albrecher and hipp ( 2007 ) introduced the idea of tax payments. more precisely, if $ x = \ { x _ t : t \ geq 0 \ } $ represents the cramer - lundberg process and, for all $ t \ geq 0 $, $ s _ t = \ sup _ { s \ leq t } x _ s $, then albrecher and hipp ( 2007 ) study $ x _ t - \ gamma s _ t $, $ t \ geq 0 $, where $ \ gamma \ in ( 0, 1 ) $ is the rate at which tax is paid. this model has been generalised to the setting that $ x $ is a spectrally negative l \ ' evy process by albrecher et al. \ cite { albr _ ren _ zhou }. finally kyprianou and zhou ( 2009 ) extend this model further by allowing the rate at which tax is paid with respect to the process $ s = \ { s _ t : t \ geq 0 \ } $ to vary as a function of the current value of $ s $. specifically, they consider the so - called perturbed spectrally negative levy process, \ [ u _ t = x _ t - \ int _ { ( 0, t ] } \ gamma ( s _ u ) \, { \ rm d } s _ u, \ qquad t \ geq 0, \ ] under the assumptions $ \ gamma : [ 0, \ infty ) \ rightarrow [ 0, 1 ) $ and $ \ int _ 0 ^ \ infty ( 1 - \ gamma ( s ) ) { \ rm d } s = \ infty $. in this article we show that a number of the identities in kyprianou and zhou ( 2009 ) are still valid for a much more general class of rate functions $ \ gamma : [ 0, \ infty ) \ rightarrow \ mathbb { r } $. moreover, we show that, with appropriately chosen $ \ gamma $, the perturbed process can pass continuously ( ie. creep ) into $ ( - \ infty, 0 ) $ in two different ways.
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arxiv:1204.1676
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we prove cases of a conjectural rule of h. yadav, a. yong, and the author for structure coefficients of the d. anderson - w. fulton ring. in particular, we give a combinatorial description for certain localization coefficients of this ring, which is related to the equivariant cohomology of isotropic grassmannians.
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arxiv:2111.02971
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women in sociological studies, analysis, and courses. in 1969, feminist sociologists challenged the discipline ' s androcentrism at the american sociological association ' s annual conference. this led to the founding of the organization sociologists for women in society, and, eventually, a new sociology journal, gender & society. today, the sociology of gender is considered to be one of the most prominent sub - fields in the discipline. new sociological sub - fields continue to appear — such as community studies, computational sociology, environmental sociology, network analysis, actor - network theory, gender studies, and a growing list, many of which are cross - disciplinary in nature. = = additional fields of study = = additional applied or interdisciplinary fields related to the social sciences or are applied social sciences include : archaeology, a science that is focused on the study of human cultures by means of the recovery, documentation, analysis, and interpretation of material remains and environmental data, including architecture, artifacts, features, and landscapes. area studies, interdisciplinary fields of research and scholarship pertaining to particular geographical, national / federal, or cultural regions. behavioural science, which encompasses disciplines that explore the activities of and interactions among organisms in the natural world. computational social science, an umbrella field encompassing computational approaches within the social sciences. demography, the statistical study of human populations. development studies, a branch of social science that addresses issues of concern to developing countries. environmental social science, the broad study of interrelations between humans and the natural environment. environmental studies, which integrates social, humanistic, and natural science perspectives on the relation between humans and the natural environment. gender studies, which is focused on the study of gender identity, masculinity, femininity, transgender issues, and sexuality. information science, an interdisciplinary science primarily concerned with the collection, classification, manipulation, storage, retrieval and dissemination of information. international studies, which covers both international relations ( the study of foreign affairs and global issues among states within the international system ) and international education. legal management, a social sciences discipline that is designed for students interested in the study of state and legal elements. library science, a field that applies the practices, perspectives, and tools of management, information technology, education, and other areas to libraries ; and the collection, organization, preservation and dissemination of information resources. management, which consists of various levels of leadership and administration of an organization in all business and human organizations. it is the effective execution of getting people together to accomplish desired goals and objectives through adequate planning, executing and
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https://en.wikipedia.org/wiki/Social_science
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we present multi - epoch vlt / sphere observations of the protoplanetary disk around hd 135344b ( sao 206462 ). the $ j $ - band scattered light imagery reveal, with high spatial resolution ( $ \ sim $ 41 mas, 6. 4 au ), the disk surface beyond $ \ sim $ 20 au. temporal variations are identified in the azimuthal brightness distributions of all epochs, presumably related to the asymmetrically shading dust distribution in the inner disk. these shadows manifest themselves as narrow lanes, cast by localized density enhancements, and broader features which possibly trace the larger scale dynamics of the inner disk. we acquired visible and near - infrared photometry which shows variations up to 10 % in the $ jhk $ bands, possibly correlated with the presence of the shadows. analysis of archival vlti / pionier $ h $ - band visibilities constrain the orientation of the inner disk to $ i = 18. 2 \ deg ^ { + 3. 4 } _ { - 4. 1 } $ and $ { \ rm pa } = 57. 3 \ deg \ pm 5. 7 \ deg $, consistent with an alignment with the outer disk or a minor disk warp of several degrees. the latter scenario could explain the broad, quasi - stationary shadowing in n - nw direction in case the inclination of the outer disk is slightly larger. the correlation between the shadowing and the near - infrared excess is quantified with a grid of radiative transfer models. the variability of the scattered light contrast requires extended variations in the inner disk atmosphere ( $ h / r \ lesssim 0. 2 $ ). possible mechanisms that may cause asymmetric variations in the optical depth ( $ \ delta \ tau \ lesssim1 $ ) through the atmosphere of the inner disk include turbulent fluctuations, planetesimal collisions, or a dusty disk wind, possibly enhanced by a minor disk warp. a fine temporal sampling is required to follow day - to - day changes of the shadow patterns which may be a face - on variant of the ux orionis phenomenon.
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arxiv:1710.02532
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we calculate the one loop partition function for topologically massive higher spin gravity ( tmhsg ) for arbitrary spin by taking the spin - 3 tmhsg action constructed in arxiv : 1107. 0915 and subsequently generalising it for an arbitrary spin. we find that the final result can be put into a product form which cannot be holomorphically factorized giving strong evidence that the topologically massive higher spin gravity is dual to a high spin extension of logarithmic cft rather than a chiral one.
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arxiv:1107.2063
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the problem of a physical relevance ( meaning ) of percolation in supercritical fluids is addressed considering a primitive model of water. two different criteria, physical and configurational, are used for the cluster definition in monte carlo simulations over a range of pressures to determine the percolation line and skewness, and a theoretical analytic equation of state is used to evaluate response functions. it is found that both criteria yield practically the same percolation line. however, unlike the findings for simple fluids, the loci of the response function extrema exhibit density / pressure dependence quite different from that of the percolation line. the only potential coincidence between the loci of the extrema of a thermodynamic property and a detectable structural change is found for the coefficient of isothermal compressibility and voronoi neighbors distribution skewness maximum.
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arxiv:1207.3263
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the lasso is a variable subset selection procedure in statistical linear regression based on $ \ ell _ 1 $ penalization of the least - squares operator. uniqueness of the lasso is an important issue, especially for the study of the lasso path. the goal of the present paper is to provide a generic sufficient condition on the design matrix for the lasso minimizer to be unique. unlike previous works on the question of uniqueness, our condition only depends on the design matrix. our study is based on a general position condition on the design matrix which holds with probability one for most experimental models.
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arxiv:1105.1430
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sic is set to enable a new era in power electronics impacting a wide range of energy technologies, from electric vehicles to renewable energy. its physical characteristics outperform silicon in many aspects, including band gap, breakdown field, and thermal conductivity. the main challenge for further development of sic - based power semiconductor devices is the quality of the interface between sic and its native dielectric sio $ _ 2 $. high temperature nitridation processes can improve the interface quality and ultimately the device performance immensely, but the underlying chemical processes are still poorly understood. here, we present an energy - dependent hard x - ray photoelectron spectroscopy ( haxpes ) study probing non - destructively sic and sio $ _ 2 $ and their interface in device stacks treated in varying atmospheres. we successfully combine laboratory - and synchrotron - based haxpes to provide unique insights into the chemistry of interface defects and their passivation through nitridation processes.
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arxiv:1912.06592
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the spin - energy $ e _ { rot } $ of a kerr black hole surrounded by a torus may power emissions in multiple windows. the recently determined true grb - energy of $ 3 - 5 \ times 10 ^ { 50 } $ erg indicates a minor fraction $ e _ j / e _ { rot } \ simeq 0. 1 % $ in baryon poor ouput, here considered as jets along open magnetic flux - tubes from the horizon to infinity. a major fraction $ e _ { gw } / e _ { rot } \ simeq 5 % $ is expected in gravitational radiation from the torus. a ligo / virgo detection of $ \ alpha = 2 \ pi \ int fde _ { gw } $ in excess of the neutron star limit $ \ alpha ^ * \ simeq 0. 005 $ promises a calorimetric test for kerr black holes. we expect a sample of ligo / virgo detections to obey the distribution of redshift corrected grb - durations.
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arxiv:astro-ph/0112219
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we study the problem of gravitational lensing by binary galaxies, idealized as two isothermal spheres. in a wide binary, each galaxy possesses individual tangential, nearly astroidal, caustics and roundish radial caustics. as the separation of the binary is made smaller, the caustics undergo a sequence of metamorphoses. the first metamorphosis occurs when the tangential caustics merge to form a single six - cusped caustic, lying interior to the radial caustics. at still smaller separations, the six - cusped caustic undergoes the second metamorphosis and splits into a four - cusped caustic and two three - cusped caustics, which shrink to zero size ( an elliptic umbilic catastrophe ) before they enlarge again and move away from the origin perpendicular to the binary axis. finally, a third metamorphosis occurs as the three - cusp caustics join the radial caustics, leaving an inner distorted astroid caustic enclosed by two outer caustics. the maximum number of images possible is 7. classifying the multiple imaging according to critical isochrones, there are only 8 possibilities : 2 three - image cases, 3 five - image cases, and 3 seven - image cases. when the isothermal spheres are singular, the core images vanish into the central singularity. the number of images may then be 1, 2, 3, 4 or 5, depending on the source location, and the separation and masses of the pair of lensing galaxies. the locations of metamorphoses, and the onset of threefold and fivefold multiple imaging, can be worked out analytically in this case.
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arxiv:0804.3743
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social agents with finitely nested opponent models are vulnerable to manipulation by agents with deeper reasoning and more sophisticated opponent modelling. this imbalance, rooted in logic and the theory of recursive modelling frameworks, cannot be solved directly. we propose a computational framework, $ \ aleph $ - ipomdp, augmenting model - based rl agents ' bayesian inference with an anomaly detection algorithm and an out - of - belief policy. our mechanism allows agents to realize they are being deceived, even if they cannot understand how, and to deter opponents via a credible threat. we test this framework in both a mixed - motive and zero - sum game. our results show the $ \ aleph $ mechanism ' s effectiveness, leading to more equitable outcomes and less exploitation by more sophisticated agents. we discuss implications for ai safety, cybersecurity, cognitive science, and psychiatry.
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arxiv:2405.01870
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thanks to the rapid advances in deep learning techniques and the wide availability of large - scale training sets, the performance of video saliency detection models has been improving steadily and significantly. however, deep learning - based visualaudio fixation prediction is still in its infancy. at present, only a few visual - audio sequences have been furnished, with real fixations being recorded in real visual - audio environments. hence, it would be neither efficient nor necessary to recollect real fixations under the same visual - audio circumstances. to address this problem, this paper promotes a novel approach in a weakly supervised manner to alleviate the demand of large - scale training sets for visual - audio model training. by using only the video category tags, we propose the selective class activation mapping ( scam ) and its upgrade ( scam + ). in the spatial - temporal - audio circumstance, the former follows a coarse - to - fine strategy to select the most discriminative regions, and these regions are usually capable of exhibiting high consistency with the real human - eye fixations. the latter equips the scam with an additional multi - granularity perception mechanism, making the whole process more consistent with that of the real human visual system. moreover, we distill knowledge from these regions to obtain complete new spatial - temporal - audio ( sta ) fixation prediction ( fp ) networks, enabling broad applications in cases where video tags are not available. without resorting to any real human - eye fixation, the performances of these sta fp networks are comparable to those of fully supervised networks. the code and results are publicly available at https : / / github. com / guotaowang / stanet.
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arxiv:2112.13697
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##nt estimates for $ \ mathcal { l } _ { \ infty } $. then we prove that the schwartz space is a core of $ a _ p $ and apply an $ l ^ p $ - solvability result of the resolvent equation for $ a _ p $. a second characterization shows that the maximal domain even coincides with \ begin { align * } \ mathcal { d } ^ p _ { \ mathrm { max } } ( \ mathcal { l } _ 0 ) = \ { v \ in w ^ { 2, p } \ mid \ left \ langle s \ cdot, \ nabla v \ right \ rangle \ in l ^ p \ }, \, 1 < p < \ infty. \ end { align * } this second characterization is based on the first one, and its proof requires $ l ^ p $ - regularity for the cauchy problem associated with $ a _ p $. finally, we show a $ w ^ { 2, p } $ - resolvent estimate for $ \ mathcal { l } _ { \ infty } $ and an $ l ^ p $ - estimate for the drift term $ \ langle s \ cdot, \ nabla v \ rangle $.
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arxiv:1510.00827
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we present a large deviation principle for some stochastic evolution equations with jumps which depend on two small parameters, when the viscosity parameter { \ epsilon } tends to zero more quickly than the homogenization ' s one { \ delta } { \ epsilon } ( written as a function of { \ epsilon } ). in particular, we highlighted a large deviation principle in path - space using some classical techniques and a uniform upper bound for the characteristic function of a feller process.
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arxiv:1909.07300
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sequential recommendation aims to model dynamic user behavior from historical interactions. self - attentive methods have proven effective at capturing short - term dynamics and long - term preferences. despite their success, these approaches still struggle to model sparse data, on which they struggle to learn high - quality item representations. we propose to model user dynamics from shopping intents and interacted items simultaneously. the learned intents are coarse - grained and work as prior knowledge for item recommendation. to this end, we present a coarse - to - fine self - attention framework, namely cafe, which explicitly learns coarse - grained and fine - grained sequential dynamics. specifically, cafe first learns intents from coarse - grained sequences which are dense and hence provide high - quality user intent representations. then, cafe fuses intent representations into item encoder outputs to obtain improved item representations. finally, we infer recommended items based on representations of items and corresponding intents. experiments on sparse datasets show that cafe outperforms state - of - the - art self - attentive recommenders by 44. 03 % ndcg @ 5 on average.
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arxiv:2204.01839
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despite numerous successes in deep reinforcement learning ( drl ), the learned policies are not interpretable. moreover, since drl does not exploit symbolic relational representations, it has difficulties in coping with structural changes in its environment ( such as increasing the number of objects ). relational reinforcement learning, on the other hand, inherits the relational representations from symbolic planning to learn reusable policies. however, it has so far been unable to scale up and exploit the power of deep neural networks. we propose deep explainable relational reinforcement learning ( derrl ), a framework that exploits the best of both - - neural and symbolic worlds. by resorting to a neuro - symbolic approach, derrl combines relational representations and constraints from symbolic planning with deep learning to extract interpretable policies. these policies are in the form of logical rules that explain how each decision ( or action ) is arrived at. through several experiments, in setups like the countdown game, blocks world, gridworld, and traffic, we show that the policies learned by derrl can be applied to different configurations and contexts, hence generalizing to environmental modifications.
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arxiv:2304.08349
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online enrichment is the extension of a reduced solution space based on the solution of the reduced model. procedures for online enrichment were published for many localized model order reduction techniques. we show that residual based online enrichment on overlapping domains converges exponentially. furthermore, we present an optimal enrichment strategy which couples the global reduced space with a local fine space. numerical experiments on the two dimensional stationary heat equation with high contrast and channels confirm and illustrate the results.
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arxiv:1710.02104
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we investigated the onsager relations in the context of electromagnetic constitutive relations of linear, homogeneous materials. we determined that application of the onsager relations to the constitutive equations relating $ # p $ and $ # m $ to both $ # e $ and $ # b $ is in accord with lorentz reciprocity as well as the post constraint.
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arxiv:physics/0411231
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several researchers have recently explored various graph parameters that can or cannot be characterized by the spectrum of a matrix associated with a graph. in this paper we show that several np - hard zero forcing numbers are not characterized by the spectra of several types of associated matrices with a graph. in particular, we consider standard zero forcing, positive semidefinite zero forcing, and skew zero forcing, and provide constructions of infinite families of pairs of cospectral graphs which have different values for these numbers. we explore several methods for obtaining these cospectral graphs including using graph products, graph joins, and graph switching. among these, we provide a construction involving regular adjacency cospectral graphs ; the regularity of this construction also implies cospectrality with respect to several other matrices including the laplacian, signless laplacian, and normalized laplacian. we also provide a construction where pairs of cospectral graphs can have an arbitrarily large difference between their zero forcing numbers.
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arxiv:2111.12343
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variational models for image deblurring problems typically consist of a smooth term and a potentially non - smooth convex term. a common approach to solving these problems is using proximal gradient methods. to accelerate the convergence of these first - order iterative algorithms, strategies such as variable metric methods have been introduced in the literature. in this paper, we prove that, for image deblurring problems, the variable metric strategy can be reinterpreted as a right preconditioning method. consequently, we explore an inexact left - preconditioned version of the same proximal gradient method. we prove the convergence of the new iteration to the minimum of a variational model where the norm of the data fidelity term depends on the preconditioner. the numerical results show that left and right preconditioning are comparable in terms of the number of iterations required to reach a prescribed tolerance, but left preconditioning needs much less cpu time, as it involves fewer evaluations of the preconditioner matrix compared to right preconditioning. the quality of the computed solutions with left and right preconditioning are comparable. finally, we propose some non - stationary sequences of preconditioners that allow for fast and stable convergence to the solution of the variational problem with the classical $ \ ell ^ 2 $ - - norm on the fidelity term.
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arxiv:2409.13454
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two words are $ k $ - binomially equivalent whenever they share the same subwords, i. e., subsequences, of length at most $ k $ with the same multiplicities. this is a refinement of both abelian equivalence and the simon congruence. the $ k $ - binomial complexity of an infinite word $ \ mathbf { x } $ maps the integer $ n $ to the number of classes in the quotient, by this $ k $ - binomial equivalence relation, of the set of factors of length $ n $ occurring in $ \ mathbf { x } $. this complexity measure has not been investigated very much. in this paper, we characterize the $ k $ - binomial complexity of the thue - - morse word. the result is striking, compared to more familiar complexity functions. although the thue - - morse word is aperiodic, its $ k $ - binomial complexity eventually takes only two values. in this paper, we first obtain general results about the number of occurrences of subwords appearing in iterates of the form $ \ psi ^ \ ell ( w ) $ for an arbitrary morphism $ \ psi $. we also thoroughly describe the factors of the thue - - morse word by introducing a relevant new equivalence relation.
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arxiv:1812.07330
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we present a route towards the quantum simulation of exotic quantum magnetism in ion traps by exploiting dual relations between different spin models. our strategy allows one to start from hamiltonians that can be realized with current technology, while properties of an exotic dual model are inferred from measurements of non - local, string - order - like, operators. the latter can be achieved from fluorescence, or from certain spectroscopic measurements, both of which can be combined with finite - size scaling by controlling the number of ions in the dual quantum simulator. we apply this concept to propose quantum simulators of frustrated quantum magnets, and ising models with multi - spin interactions. we test the validity of the idea by showing numerically that the predictions of an ideal dual quantum simulator are not qualitatively modified by relevant perturbations that occur naturally in the trapped - ion scenario.
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arxiv:1511.04323
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on a $ 2m $ - dimensional closed manifold we investigate the existence of prescribed $ q $ - curvature metrics with conical singularities. we present here a general existence and multiplicity result in the supercritical regime. to this end, we first carry out a blow - up analysis of a $ 2m $ th - order pde associated to the problem and then apply a variational argument of min - max type. for $ m > 1 $, this seems to be the first existence result for supercritical conic manifolds different from the sphere.
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arxiv:2206.06006
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adherence to scientific community standards ensures objectivity, clarity, reproducibility, and helps prevent bias, fabrication, falsification, and plagiarism. to help scientific integrity officers and journal / publisher reviewers monitor if researchers stick with these standards, it is important to have a solid procedure to detect duplication as one of the most frequent types of manipulation in scientific papers. images in scientific papers are used to support the experimental description and the discussion of the findings. therefore, in this work we focus on detecting the duplications in images as one of the most important parts of a scientific paper. we propose a framework that combines image processing and deep learning methods to classify images in the articles as duplicated or unduplicated ones. we show that our method leads to a 90 % accuracy rate of detecting duplicated images, a ~ 13 % improvement in detection accuracy in comparison to other manipulation detection methods. we also show how effective the pre - processing steps are by comparing our method to other state - of - art manipulation detectors which lack these steps.
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arxiv:2102.01874
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we prove that various git semistabilities of polarized varieties imply semi - log - canonicity.
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arxiv:0807.1716
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living organisms maintain stable functioning amid environmental fluctuations through homeostasis, a property that preserves a system ' s behavior despite changes in environmental conditions. to elucidate homeostasis in stochastic biochemical reactions, theoretical tools for assessing population - level invariance under parameter perturbations are crucial. in this paper, we propose a systematic method for identifying the stationary moments that remain invariant under parameter perturbations by leveraging the structural properties of the stationary moment equations. a key step in this development is addressing the underdetermined nature of moment equations, which has traditionally made it difficult to characterize how stationary moments depend on system parameters. to overcome this, we utilize the dulmage - mendelsohn ( dm ) decomposition of the coefficient matrix to extract welldetermined subequations and reveal their hierarchical structure. leveraging this structure, we identify stationary moments whose partial derivatives with respect to parameters are structurally zero, facilitating the exploration of fundamental constraints that govern homeostatic behavior in stochastic biochemical systems.
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arxiv:2503.13336
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this article gives an overview of different database encryption choices in sql server. which one works best in which situation. in today ' s world data is more crucial than the expensive hardware cost. no one wants their personal data to be comprised. same for business houses as well and they also do not want their data to be inappropriately handled to go out of the business. to help protect the public rights and safety, recently this year, the european union had come up with strict rules and regulation of gdpr ( general data protection regulation ).
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arxiv:1901.03179
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this paper is devoted to a systematic study of certain geometric integral inequalities which arise in continuum combinatorial approaches to $ l ^ p $ - improving inequalities for radon - like transforms over polynomial submanifolds of intermediate dimension. the desired inequalities relate to and extend a number of important results in geometric measure theory.
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arxiv:1906.04599
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video compression benefits from advanced chroma intra prediction methods, such as the cross - component linear model ( cclm ) which uses linear models to approximate the relationship between the luma and chroma components. recently it has been proven that advanced cross - component prediction methods based on neural networks ( nn ) can bring additional coding gains. in this paper, spatial information refinement is proposed for improving nn - based chroma intra prediction. specifically, the performance of chroma intra prediction can be improved by refined down - sampling or by incorporating location information. experimental results show that the two proposed methods obtain 0. 31 %, 2. 64 %, 2. 02 % and 0. 33 %, 3. 00 %, 2. 12 % bd - rate reduction on y, cb and cr components, respectively, under all - intra configuration, when implemented in versatile video coding ( h. 266 / vvc ) test model. index terms - chroma intra prediction, convolutional neural networks, spatial information refinement.
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arxiv:2109.11913
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we report the detection of hot h $ _ { 2 } $ o and oh emission from the herbig ae / be star hd $ ~ 101412 $ using the cryogenic infrared echelle spectrograph on the $ \ textit { very large telescope } $. previous studies of herbig ae / be stars have shown the presence of oh around some of these sources, but h $ _ { 2 } $ o has proven more elusive. while marginal water emission has been reported in the mid - infrared, and a few herbig ae / be stars show water emission in the far - infrared, water emission near 2. 9 $ \ mu $ m has not been previously detected. we apply slab models to the ro - vibrational oh, h $ _ { 2 } $ o, and co spectra of this source and show that the molecules are consistent with being cospatial. we discuss the possibility that the detection of the co overtone bandhead emission, detection of water emission, and the large line to continuum contrast of the oh lines may be connected to its high inclination and the $ \ lambda $ bo \ " o nature of this star. if the low abundance of refractories results from the selective accretion of gas relative to dust, the inner disk of hd $ ~ 101412 $ should be strongly dust - depleted allowing us to probe deeper columns of molecular gas in the disk, enhancing its molecular emission. our detection of c - and o - bearing molecules from the inner disk of hd $ ~ 101412 $ is consistent with the expected presence in this scenario of abundant volatiles in the accreting gas.
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arxiv:1812.07094
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recent advances in machine learning have enabled generative models for both optimization and de novo generation of drug candidates with desired properties. previous generative models have focused on producing smiles strings or 2d molecular graphs, while attempts at producing molecules in 3d have focused on reinforcement learning ( rl ), distance matrices, and pure atom density grids. here we present molucinate ( molecular convolutional generative model ), a novel architecture that simultaneously generates topological and 3d atom position information. we demonstrate the utility of this method by using it to optimize molecules for desired radius of gyration. in the future, this model can be used for more useful optimization such as binding affinity for a protein target.
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arxiv:2109.15308
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this work presents the catalogue of optical spectral properties for all x - ray selected spiders active galactic nuclei ( agn ) up to sdss dr14. spiders ( spectroscopic identification of erosita sources ) is an sdss - iv programme that is currently conducting optical spectroscopy of the counterparts to the x - ray selected sources detected in the rosat all - sky survey and the xmm - newton slew survey in the footprint of the extended baryon oscillation spectroscopic survey ( eboss ). the spiders dr14 sample is the largest sample of x - ray selected agn with optical spectroscopic follow - up to date. the catalogue presented here is based on a clean sample of 7344 2rxs ( $ \ rm \ bar { z } $ = 0. 5 ) and 1157 xmm - newton slew survey ( $ \ rm \ bar { z } $ = 0. 4 ) type 1 agn with spectroscopic coverage of the h $ \ rm \ beta $ and / or mgii emission lines. visual inspection results for each object in this sample are available from a combination of literature sources and the spiders group, which provide both reliable redshifts and source classifications. the spectral regions around the h $ \ rm \ beta $ and mgii emission lines have been fit in order to measure both line and continuum properties, estimate bolometric luminosities, and provide black hole mass estimates using the single - epoch ( or photoionisation ) method. the use of both h $ \ rm \ beta $ and mgii allows black hole masses to be estimated up to z $ \ rm \ simeq $ 2. 5. a comparison is made between the spectral properties and black hole mass estimates derived from h $ \ rm \ beta $ and mgii using the subsample of objects which have coverage of both lines in their spectrum. these results have been made publicly available as an sdss - iv dr14 value added catalogue.
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arxiv:1904.10780
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learning compact binary codes for image retrieval problem using deep neural networks has recently attracted increasing attention. however, training deep hashing networks is challenging due to the binary constraints on the hash codes. in this paper, we propose deep network models and learning algorithms for learning binary hash codes given image representations under both unsupervised and supervised manners. the novelty of our network design is that we constrain one hidden layer to directly output the binary codes. this design has overcome a challenging problem in some previous works : optimizing non - smooth objective functions because of binarization. in addition, we propose to incorporate independence and balance properties in the direct and strict forms into the learning schemes. we also include a similarity preserving property in our objective functions. the resulting optimizations involving these binary, independence, and balance constraints are difficult to solve. to tackle this difficulty, we propose to learn the networks with alternating optimization and careful relaxation. furthermore, by leveraging the powerful capacity of convolutional neural networks, we propose an end - to - end architecture that jointly learns to extract visual features and produce binary hash codes. experimental results for the benchmark datasets show that the proposed methods compare favorably or outperform the state of the art.
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arxiv:1712.02956
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a detailed next - to - next - to - leading order ( nnlo ) qcd analysis is performed for the experimental data of the ccfr collaboration for the $ xf _ 3 $ structure function. theoretical ambiguities of the results of our nnlo fits are estimated by application of the pad \ ' e resummation technique and variation of the factorization and renormalization scales. the nnlo and n $ ^ 3 $ lo $ \ alpha _ s ( q ^ 2 ) $ $ \ bar { ms } $ - matching conditions are used. in the process of the fits we are taking into account of twist - 4 $ 1 / q ^ 2 $ - terms. we found that the amplitude of the $ x $ - shape of the twist - 4 factor is decreasing in nlo and nnlo, though some remaining twist - 4 structure seems to retain in nnlo in the case when statistical uncertainties are taken into account. the question of the stability of these results to the application of the [ 0 / 2 ] pad \ ' e resummation technique is considered. our nnlo results for $ \ alpha _ s ( m _ z ) $ values, extracted from the ccfr $ xf _ 3 $ data, are $ \ alpha _ s ( m _ z ) = 0. 118 \ pm 0. 002 ( stat ) \ pm 0. 005 ( syst ) \ pm 0. 003 ( theory ) $ provided the twist - 4 contributions are fixed through the infrared renormalon model and $ \ alpha _ s ( m _ z ) = 0. 121 ^ { + 0. 007 } _ { 0. 010 } ( stat ) \ pm 0. 005 ( syst ) \ pm 0. 003 ( theory ) $ provided the twist - 4 terms are considered as free parameters.
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arxiv:hep-ph/9905310
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we estimate the uv continuum slope, beta, for 923 galaxies in the range 1 < z < 8 in the hubble ultradeep field ( hudf ). these data include 460 galaxies at 1 < z < 2 down to an absolute magnitude m _ { uv } = - 14 ( ~ 0. 006 l * _ { z = 1 } ; 0. 02 l * _ { z = 0 } ), comparable to dwarf galaxies in the local universe. we combine deep hst / uvis photometry in f225w, f275w, f336w wavebands ( uvudf ) with recent data from hst / wfc3 / ir ( hudf12 ). galaxies in the range 1 < z < 2 are significantly bluer than local dwarf galaxies. we find their mean ( median ) values < beta > = - 1. 382 ( - 1. 830 ) + / - 0. 002 ( random ) + / - 0. 1 ( systematic ). we find comparable scatter in beta ( standard deviation = 0. 43 ) to local dwarf galaxies and 30 % larger scatter than z > 2 galaxies. we study the trends of beta with redshift and absolute magnitude for binned sub - samples and find a modest color - magnitude relation, dbeta / dm = - 0. 11 + / - 0. 01 and no evolution in dbeta / dm with redshift. a modest increase in dust reddening with redshift and luminosity, delta e ( b - v ) ~ 0. 1, and a comparable increase in the dispersion of dust reddening at z < 2, appears likely to explain the observed trends. at z > 2, we find trends that are consistent with previous works ; combining our data with the literature in the range 1 < z < 8, we find a color evolution with redshift, dbeta / dz = - 0. 09 + / - 0. 01 for low luminosity ( 0. 05 l * _ { z = 3 } ), and dbeta / dz = - 0. 06 + / - 0. 01 for medium luminosity ( 0. 25 l * _ { z = 3 } ) galaxies.
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arxiv:1407.3680
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a growing number of software - intensive systems are being accused of violating or ignoring human values ( e. g., privacy, inclusion, and social responsibility ), and this poses great difficulties to individuals and society. such violations often occur due to the solutions employed and decisions made by developers of such systems that are misaligned with user values. stack overflow is the most popular qa website among developers to share their issues, solutions ( e. g., code snippets ), and decisions during software development. we conducted an exploratory study to investigate the occurrence of human values violations in stack overflow posts. as comments under posts are often used to point out the possible issues and weaknesses of the posts, we analyzed 2000 stack overflow comments and their corresponding posts ( 1980 unique questions or answers ) to identify the types of human values violations and the reactions of stack overflow users to such violations. our study finds that 315 out of 2000 comments contain concerns indicating their associated posts ( 313 unique posts ) violate human values. leveraging schwartz ' s theory of basic human values as the most widely used values model, we show that hedonism and benevolence are the most violated value categories. we also find the reaction of stack overflow commenters to perceived human values violations is very quick, yet the majority of posts ( 76. 35 % ) accused of human values violation do not get downvoted at all. finally, we find that the original posters rarely react to the concerns of potential human values violations by editing their posts. at the same time, they usually are receptive when responding to these comments in follow - up comments of their own.
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arxiv:2203.10551
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we present a novel algorithm to detect double nuclei galaxies ( dng ) called gothic ( graph boosted iterated hill climbing ) - that detects whether a given image of a galaxy has two or more closely separated nuclei. our aim is to detect samples of dual or multiple active galactic nuclei ( agn ) in galaxies. although galaxy mergers are common, the detection of dual agn is rare. their detection is very important as they help us understand the formation of supermassive black hole ( smbh ) binaries, smbh growth and agn feedback effects in multiple nuclei systems. there is thus a need for an algorithm to do a systematic survey of existing imaging data for the discovery of dngs and dual agn. we have tested gothic on a known sample of dngs and subsequently applied it to a sample of a million sdss dr16 galaxies lying in the redshift range of 0 to 0. 75 approximately, and have available spectroscopic data. we have detected 159 dual agn in this sample, of which 2 are triple agn systems. our results show that dual agn are not common, and triple agn even rarer. the color ( u - r ) magnitude plots of the dngs indicate that star formation is quenched as the nuclei come closer and as the agn fraction increases. the quenching is especially prominent for dual / triple agn galaxies that lie in the extreme end of the red sequence.
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arxiv:2011.12177
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the possibility of the magnetic monopole decay in the constant electric field is investigated and the exponential factor in the probability is obtained. corrections due to coulomb interaction are calculated. the relation between masses of particles for the process to exist is obtained.
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arxiv:hep-th/0509047
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in this paper, we revisit the notion of length measures associated to planar closed curves. these are a special case of area measures of hypersurfaces which were introduced early on in the field of convex geometry. the length measure of a curve is a measure on the circle $ \ mathbb { s } ^ 1 $ that intuitively represents the length of the portion of curve which tangent vector points in a certain direction. while a planar closed curve is not characterized by its length measure, the fundamental minkowski - fenchel - jessen theorem states that length measures fully characterize convex curves modulo translations, making it a particularly useful tool in the study of geometric properties of convex objects. the present work, that was initially motivated by problems in shape analysis, introduces length measures for the general class of lipschitz immersed and oriented planar closed curves, and derives some of the basic properties of the length measure map on this class of curves. we then focus specifically on the case of convex shapes and present several new results. first, we prove an isoperimetric characterization of the unique convex curve associated to some length measure given by the minkowski - fenchel - jessen theorem, namely that it maximizes the signed area among all the curves sharing the same length measure. second, we address the problem of constructing a distance with associated geodesic paths between convex planar curves. for that purpose, we introduce and study a new distance on the space of length measures that corresponds to a constrained variant of the wasserstein metric of optimal transport, from which we can induce a distance between convex curves. we also propose a primal - dual algorithm to numerically compute those distances and geodesics, and show a few simple simulations to illustrate the approach.
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arxiv:2010.13964
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in this paper, we obtain several extensions of semi - fredholm theory on hilbert modules by generalizing in this setting their classical counterparts regarding weyl operators and drazin invertible operators.
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arxiv:2302.05533
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we investigate the casimir stress on a topological insulator ( ti ) between two metallic plates. the ti is assumed to be joined to one of the plates and its surface in front of the other is covered by a thin magnetic layer, which turns the ti into a full insulator. we also analyze the limit where one of the plates is sent to infinity yielding the casimir stress between a conducting plate and a ti. to this end we employ a local approach in terms of the stress - energy tensor of the system, its vacuum expectation value being subsequently evaluated in terms of the appropriate green ' s function. finally, the construction of the renormalised vacuum stress - energy tensor in the region between the plates yields the casimir stress. numerical results are also presented.
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arxiv:1604.00534
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we introduce a generic scheme to perform non - perturbative linked cluster expansions in long - range ordered quantum phases. clusters are considered to be surrounded by an ordered reference state leading to effective edge - fields in the exact diagonalization on clusters which break the associated symmetry of the ordered phase. two approaches, based either on a self - consistent solution of the order parameter or on minimal sensitivity with respect to the ground - state energy per site, are formulated to find the optimal edge - field in each nlce order. furthermore, we investigate the scaling behavior of the nlce data sequences towards the infinite - order limit. we apply our scheme to gapped and gapless ordered phases of xxz heisenberg models on various lattices and for spins 1 / 2 and 1 using several types of cluster expansions ranging from a full - graph decomposition, rectangular clusters, up to more symmetric square clusters. it is found that the inclusion of edge - fields allows to regularize non - perturbative linked - cluster expansions in ordered phases yielding convergent data sequences. this includes the long - range spin - ordered ground state of the spin - 1 / 2 and spin - 1 heisenberg model on the square and triangular lattice as well as the trimerized valence bond crystal of the spin - 1 heisenberg model on the kagome lattice.
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arxiv:1608.05618
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among the potential applications of topological insulators, we theoretically study the coexistence of proximity - induced ferromagnetic and superconducting orders in the surface states of a 3 - dimensional topological insulator. the superconducting electron - hole excitations can be significantly affected by the magnetic order induced by a ferromagnet. in one hand, the surface state of the topological insulator, protected by the time - reversal symmetry, creates a spin - triplet and, on the other hand, magnetic order causes to renormalize the effective superconducting gap. we find majorana mode energy along the ferromagnet / superconductor interface to sensitively depend on the magnitude of magnetization $ m _ { zfs } $ from superconductor region, and its slope around perpendicular incidence is steep with very low dependency on $ m _ { zfs } $. the superconducting effective gap is renormalized by a factor $ \ eta ( m _ { zfs } ) $, and andreev bound state in ferromagnet - superconductor / ferromagnet / ferromagnet - superconductor ( fs / f / fs ) josephson junction is more sensitive to the magnitude of magnetizations of fs and f regions. in particular, we show that the presence of $ m _ { zfs } $ has a noticeable impact on the gap opening in andreev bound state, which occurs in finite angle of incidence. this directly results in zero - energy andreev state being dominant. by introducing the proper form of corresponding dirac spinors for fs electron - hole states, we find that via the inclusion of $ m _ { zfs } $, the josephson supercurrent is enhanced and exhibits almost abrupt crossover curve, featuring the dominant zero - energy majorana bound states.
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arxiv:1701.08277
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the dynamical mass generation for gluons is discussed in euclidean yang - mills theories supplemented with a renormalizable mass term. the mass parameter is not free, being determined in a self - consistent way through a gap equation which obeys the renormalization group. the example of the landau gauge is worked out explicitly at one loop order. a few remarks on the issue of the unitarity are provided.
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arxiv:0704.3186
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in this paper we study a model of the two - dimensional quantum harmonic oscillator in a 3 - dimensional anti - de sitter background. we use a generalized schr \ " odinger picture in which the analogs of the schr \ " odinger operators of the particle are independent of both the time and the space coordinates in different representations. the spacetime independent operators of the particle induce the lie algebra of killing vector fields of the $ ads _ 3 $ spacetime. in this picture, we have a metamorphosis of the heisenberg ' s uncertainty relations.
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arxiv:1601.02838
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direction - of - arrival ( doa ) estimation is one of the most demanding tasks for the millimeter wave ( mmwave ) communication of massive multiple - input multiple - output ( mimo ) systems with the hybrid beamforming ( hbf ) architecture. in this paper, we focus on the optimization of the hbf matrix for receiving pilots to enhance the doa estimation performance. motivated by the fact that many existing doa estimation algorithms can achieve the cram \ ' { e } r - rao bound ( crb ), we formulate the hbf optimization problem aiming at minimizing the crb with the prior knowledge of the rough doa range. then, to tackle the problem with intractable non - convex constraint introduced by the analog beamformers, we propose an efficient manifold optimization ( mo ) based algorithm. simulation results demonstrate the significant improvement of the proposed crb - mo algorithm over the conventional random hbf algorithm, and provide insights for the hbf design in the beam training stage for practical applications.
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arxiv:2103.15357
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in the approach recently proposed by k. costello and m. yamazaki, which is based on a four - dimensional variant of chern - simons theory, we derive a simple and unifying two - dimensional form for the action of many integrable $ \ sigma $ - models which are known to admit descriptions as affine gaudin models. this includes both the yang - baxter deformation and the $ \ lambda $ - deformation of the principal chiral model. we also give an interpretation of poisson - lie $ t $ - duality in this setting and derive the action of the $ \ mathsf { e } $ - model.
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arxiv:1909.13824
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this work presents a detailed description of the thermochemical non - equilibrium dissociation of diatomic molecules, and applies this theory to the case of $ \ rm h _ 2 $ dissociation. the master equations are used to derive corresponding aggregate rate constant expressions that hold for any degree of thermochemical non - equilibrium. these general expressions are analyzed in three key limits / regimes : the thermal equilibrium limit, the quasi - steady - state ( qss ) regime, and the pre - qss regime. under several simplifying assumptions, an analytical source term expression that holds in all of these regimes, and is only a function of the translational temperature, $ t _ { \ rm t } $, and the fraction of dissociation, $ \ phi _ { \ rm a } $, is proposed. this expression has two input parameters : the qss dissociation rate constant in the absence of recombination, $ k _ { \ rm d, nr } ( t _ { \ rm t } ) $, and a pre - qss correction factor, $ \ eta ( t _ { \ rm t } ) $. the value of $ \ eta ( t _ { \ rm t } ) $ is evaluated by comparing the predictions of the proposed expression against existing master equation simulations of a 0 - d isothermal and isochoric reactor for the case of $ \ rm h _ 2 $ dissociation with the third - bodies $ \ rm h _ 2 $, $ \ rm h $, and $ \ rm he $. despite its simple functional form, the proposed expression is able to reproduce the master equation results for the majority of the tested conditions. the best fit of $ k _ { \ rm d, nr } ( t _ { \ rm t } ) $ is then evaluated by conducting a detailed literature review. data from a wide range of experimental and computational studies are considered for the third - bodies $ \ rm h _ 2 $, $ \ rm h $, and inert gases, and fits that are valid from 200 to 20, 000 k are proposed. from this review, the uncertainty of the proposed fits are estimated to be less than a factor of two.
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arxiv:2501.01626
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of $ h $. this in turn allows us to establish the hardy - littlewood conjecture and the divisor correlation conjecture with a short average over one variable. our main new ingredients are type $ ii $ estimates obtained by developing a " contagion lemma " for nilsequences and then using this to " scale up " an approximate functional equation for the nilsequence to a larger scale. this extends an approach developed by walsh for fourier uniformity.
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arxiv:2411.05770
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this paper proposes an applicable approach to deploy the coordinative real - time sub - transmission volt - var control tool ( crest - vct ), and a holistic system integration framework considering both the energy management system ( ems ) and distribution system management system ( dms ). this provides an architectural basis and can serve as the implementation guideline of crest - vct and other advanced grid support tools, to co - optimize the operation benefits of distributed energy resources ( ders ) and assets in both transmission and distribution networks. potential communication protocols for different physical domains of a real application is included. performance and security issues are also discussed, along with specific considerations for field deployment. finally, the paper presents a viable pathway for crest - vct and other advanced grid support tools to be integrated in an open - source standardized - based platform that supports distribution utilities.
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arxiv:2103.10511
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generatect, the first approach to generating 3d medical imaging conditioned on free - form medical text prompts, incorporates a text encoder and three key components : a novel causal vision transformer for encoding 3d ct volumes, a text - image transformer for aligning ct and text tokens, and a text - conditional super - resolution diffusion model. without directly comparable methods in 3d medical imaging, we benchmarked generatect against cutting - edge methods, demonstrating its superiority across all key metrics. importantly, we evaluated generatect ' s clinical applications in a multi - abnormality classification task. first, we established a baseline by training a multi - abnormality classifier on our real dataset. to further assess the model ' s generalization to external data and performance with unseen prompts in a zero - shot scenario, we employed an external set to train the classifier, setting an additional benchmark. we conducted two experiments in which we doubled the training datasets by synthesizing an equal number of volumes for each set using generatect. the first experiment demonstrated an 11 % improvement in the ap score when training the classifier jointly on real and generated volumes. the second experiment showed a 7 % improvement when training on both real and generated volumes based on unseen prompts. moreover, generatect enables the scaling of synthetic training datasets to arbitrary sizes. as an example, we generated 100, 000 3d cts, fivefold the number in our real set, and trained the classifier exclusively on these synthetic cts. impressively, this classifier surpassed the performance of the one trained on all available real data by a margin of 8 %. last, domain experts evaluated the generated volumes, confirming a high degree of alignment with the text prompt. access our code, model weights, training data, and generated data at https : / / github. com / ibrahimethemhamamci / generatect
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arxiv:2305.16037
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we show how certain hypergeometric functions play an important role in finding fundamental solutions for a generalized tricomi operator.
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arxiv:math/0310480
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multimodal language models ( mlms ) still face challenges in fundamental visual perception tasks where specialized models excel. tasks requiring reasoning about 3d structures benefit from depth estimation, and reasoning about 2d object instances benefits from object detection. yet, mlms can not produce intermediate depth or boxes to reason over. finetuning mlms on relevant data doesn ' t generalize well and outsourcing computation to specialized vision tools is too compute - intensive and memory - inefficient. to address this, we introduce perception tokens, intrinsic image representations designed to assist reasoning tasks where language is insufficient. perception tokens act as auxiliary reasoning tokens, akin to chain - of - thought prompts in language models. for example, in a depth - related task, an mlm augmented with perception tokens can reason by generating a depth map as tokens, enabling it to solve the problem effectively. we propose aurora, a training method that augments mlms with perception tokens for improved reasoning over visual inputs. aurora leverages a vqvae to transform intermediate image representations, such as depth maps into a tokenized format and bounding box tokens, which is then used in a multi - task training framework. aurora achieves notable improvements across counting benchmarks : + 10. 8 % on blink, + 11. 3 % on cvbench, and + 8. 3 % on seed - bench, outperforming finetuning approaches in generalization across datasets. it also improves on relative depth : over + 6 % on blink. with perception tokens, aurora expands the scope of mlms beyond language - based reasoning, paving the way for more effective visual reasoning capabilities.
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arxiv:2412.03548
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a new method for stability assessment of inverter - based microgrids is presented in this paper. it leverages the notion of critical clusters - - a localized group of inverters with parameters having the highest impact on the system stability. the spectrum of the weighted network admittance matrix is proposed to decompose a system into clusters and rank them based on their distances from the stability boundary. we show that each distinct eigenvalue of this matrix is associated with one cluster, and its eigenvectors reveal a set of inverters that participate most in the corresponding cluster. the least stable or unstable clusters correspond to higher values of respective eigenvalues of the weighted admittance matrix. we also establish an upper threshold for eigenvalues that determines the stability boundary of the entire system and demonstrate that this value depends only on the grid type ( i. e. $ r / x $ ratio of the network ) and does not depend on the grid topology. therefore, the proposed method provides the stability certificate based on this upper threshold and identifies the lines or inverter droop settings needed to be adjusted to restore or improve the stability.
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arxiv:2007.09347
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deuteron elastic scattering from 15c and inelastic scattering reactions to the first excited state of 15c were studied using a radioactive beam of 15c in inverse kinematics. the scattered deuterons were measured using helios. the elastic scattering differential cross sections were analyzed using the optical model. a matter deformation length { \ delta } d = 1. 04 ( 11 ) fm has been extracted from the differential cross sections of inelastic scattering to the first excited state. the ratio of neutron and proton matrix elements mn / mp = 3. 6 ( 4 ) has been determined from this quadrupole transition. neutron effective charges and core - polarization parameters of 15c were determined and discussed. results from ab - initio no - core configuration interaction calculations were also compared with the experimental observations. this result supports a moderate core decoupling effect of the valence neutron in 15c similarly to its isotone 17o, in line with the interpretation of other neutron - rich carbon isotopes.
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arxiv:2209.12252
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the primary mission of uniprot is to support biological research by maintaining a stable, comprehensive, fully classified, richly and accurately annotated protein sequence knowledgebase, with extensive cross - references to external resources, that is freely available to the scientific community. to enable users of the knowledgebase to accurately assess the reliability of the information contained in this resource, the evidence for and provenance of the information must be recorded. this paper discusses the user requirements for this kind of metadata and the manner in which uniprotkb records it.
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arxiv:1012.1660
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we study the behavior of eigenvalues of a magnetic aharonov - bohm operator with non - half - integer circulation and dirichlet boundary conditions in a planar domain. as the pole is moving in the interior of the domain, we estimate the rate of the eigenvalue variation in terms of the vanishing order of the limit eigenfunction at the limit pole. we also provide an accurate blow - up analysis for scaled eigenfunctions and prove a sharp estimate for their rate of convergence.
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arxiv:1706.05247
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in this paper, a stochastic optimal control problem is investigated in which the system is governed by a stochastic functional differential equation. in the framework of functional it \ ^ o calculus, we build the dynamic programming principle and the related path - dependent hamilton - jacobi - bellman ( hjb ) equation. we prove that the value function is the viscosity solution of the path - dependent hjb equation.
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arxiv:1207.1194
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the distribution of young open clusters in the galactic plane within 3 kpc from the sun suggests the existence of the outer ring r1r2 ' in the galaxy. the optimum value of the solar position angle with respect to the major axis of the bar, theta _ b, providing the best agreement between the distribution of open clusters and model particles is theta _ b = 35 + / - 10 degrees. the kinematical features obtained for young open clusters and ob - associations with negative galactocentric radial velocity vr indicate the solar location near the descending segment of the outer ring r2.
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arxiv:1601.01282
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. the scichallenge project used a social media contest and student - generated content to increase the motivation of pre - university students for stem education and careers. the erasmus programme project autostem used automata to introduce stem subjects to very young children. = = = = finland = = = = the luma center is the leading advocate for stem - oriented education. its aim is to promote the instruction and research of natural sciences, mathematics, computer science, and technology across all educational levels in the country. in the native tongue luma stands for " luonnontieteellis - matemaattinen " ( lit. adj. " scientific - mathematical " ). the short is more or less a direct translation of stem, with engineering fields included by association. however, unlike stem, the term is also a portmanteau from lu and ma. to address the decline in interest in learning the areas of science, the finnish national board of education launched the luma scientific education development program. the project ' s main goal was to raise the level of finnish education and to enhance students ' competencies, improve educational practices, and foster interest in science. the initiative led to the establishment of 13 luma centers at universities across finland supervised by luma center. = = = = france = = = = the name of stem in france is industrial engineering sciences ( sciences industrielles or sciences de l ' ingenieur ). the stem organization in france is the association upsti. = = = hong kong = = = stem education has not been promoted among the local schools in hong kong until recent years. in november 2015, the education bureau of hong kong released a document titled promotion of stem education, which proposes strategies and recommendations for promoting stem education. = = = india = = = india is next only to china with stem graduates per population of 1 to 52. the total number of fresh stem graduates was 2. 6 million in 2016. stem graduates have been contributing to the indian economy with well - paid salaries locally and abroad for the past two decades. the turnaround of the indian economy with comfortable foreign exchange reserves is mainly attributed to the skills of its stem graduates. in india, women make up an impressive 43 % of stem graduates, the highest percentage worldwide. however, they hold only 14 % of stem - related jobs. additionally, among the 280, 000 scientists and engineers working in research and development institutes in the country, women represent a mere 14 % in india, omotec is providing an innovative curriculum based on stem, and
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https://en.wikipedia.org/wiki/Science,_technology,_engineering,_and_mathematics
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continuum arms, such as trunk and tentacle robots, lie between the two extremities of rigid and soft robots and promise to capture the best of both worlds in terms of manipulability, dexterity, and compliance. this paper proposes a new kinematic model for a novel constant - length continuum robot that incorporates both soft and rigid elements. in contrast to traditional pneumatically actuated, variable - length continuum arms, the proposed design utilizes a hyper - redundant rigid chain to provide extra structural strength. the proposed model introduces a reduced - order mapping to account for mechanical constraints arising from the rigid - linked chain to derive a closed - form curve parametric model. the model is numerically evaluated and the results show that the derived model is reliable.
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arxiv:1907.06518
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in this article, we present the best possible upper and lower bounds for the neuman - s \ ' andor mean in terms of the geometric combinations of harmonic and quadratic means, geometric and quadratic means, harmonic and contra - harmonic means, and geometric and contra - harmonic means.
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arxiv:1211.0089
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sometimes a simple and fast algorithm is required to detect human presence and movement with a low error rate in a controlled environment for security purposes. here a light weight algorithm has been presented that generates alert on detection of human presence and its movement towards a certain direction. the algorithm uses fixed angle cctv camera images taken over time and relies upon skeleton transformation of successive images and calculation of difference in their coordinates.
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arxiv:1506.08815
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in this work, the molar volume thermal expansion coefficient of 59 room temperature ionic liquids is compared with their van der waals volume vw. regular correlation can be discerned between the two quantities. an average free volume model, that considers the particles as hard core with attractive force, is proposed to explain the correlation in this study. a combination between free volume and lennard - jones potential is applied to explain the physical phenomena of liquids. some typical simple liquids ( inorganic, organic, metallic and salt ) are introduced to verify this hypothesis. good agreement from the theory prediction and experimental data can be obtained.
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arxiv:1404.0435
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in this paper we study a new approach in optimization that aims to search a large domain d where a given function takes large, small or specific values via an iterative optimization algorithm based on the gradient. we show that the objective function used is not directly optimizable, however, we use a trick to approximate this objective by another one at each iteration to optimize it. then we explore a use case of this algorithm in machine learning to find domains where the models output large and small values with respect of some constraints. experiments demonstrate the efficiency of this algorithm on five cases with models trained on the titanic dataset.
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arxiv:2005.10005
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the present work reported a conclusive evidence for anti - magnetic rotational ( amr ) band in an odd - odd nucleus 142eu. parity of the states of a quadrupole sequence in 142eu was firmly identified from polarization measurements using the indian national gamma array and lifetimes of some of the states in the same structure were measured using the doppler shift attenuation method. the decreasing trends of the deduced quadrupole transition strength b ( e2 ) with spin, along with increasing j ( 2 ) / b ( e2 ) values conclusively established the origin of these states as arising from antimagnetic rotation. the results were well reproduced by numerical calculations within the framework of a semi - classical geometric model.
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arxiv:1707.04417
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supersymmetry with breaking of r - parity provides an attractive way to generate neutrino masses and lepton mixing angles in accordance to present neutrino data. we review the main theoretical features of the bilinear r - parity breaking ( brpv ) model, and stress that it is the simplest extension of the minimal supersymmetric standard model ( mssm ) which includes lepton number violation. we describe how it leads to a successful phenomenological model with hierarchical neutrino masses. in contrast to seesaw models, the brpv model can be probed at future collider experiments, like the large hadron collider or the next linear collider, since the decay pattern of the lightest supersymmetric particle provides a direct connection with the lepton mixing angles determined by neutrino experiments.
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arxiv:hep-ph/0405015
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metrics for rigorously defining a distance between two events have been used to study the properties of the dataspace manifold of particle collider physics. the probability distribution of pairwise distances on this dataspace is unique with probability 1, and so this suggests a method to search for and identify new physics by the deviation of measurement from a null hypothesis prediction. to quantify the deviation statistically, we directly calculate the probability distribution of the number of event pairs that land in the bin a fixed distance apart. this distribution is not generically gaussian and the ratio of the standard deviation to the mean entries in a bin scales inversely with the square - root of the number of events in the data ensemble. if the dataspace manifold exhibits some enhanced symmetry, the number of entries is gaussian, and further fluctuations about the mean scale away like the inverse of the number of events. we define a robust measure of the non - gaussianity of the bin - by - bin statistics of the distance distribution, and demonstrate in simulated data of jets from quantum chromodynamics sensitivity to the parton - to - hadron transition and that the manifold of events enjoys enhanced symmetries as their energy increases.
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arxiv:2503.03809
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interplay between quantum interference and classical randomness can enhance performance of various quantum information tasks. in the present paper we analyze recurrence phenomena in the discrete - time quantum stochastic walk on a line, which is a quantum stochastic process that interpolates between quantum and classical walk dynamics. surprisingly, we find that introducing classical randomness can reduce the recurrence probability - - despite the fact that the classical random walk returns with certainty - - and we identify the conditions under which this intriguing phenomenon occurs. numerical evaluation of the first - return generating function allows us to investigate the asymptotics of the return probability as the step number approaches infinity. this provides strong evidence that the suppression of recurrence probability is not a transient effect but a robust feature of the underlying quantum - classical interplay in the asymptotic limit. our results show that for certain tasks discrete - time quantum stochastic walks outperform both classical random walks and unitary quantum walks.
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arxiv:2501.08674
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we study separability properties in a 5 - dimensional set of states of quantum systems composed of three subsystems of equal but arbitrary finite hilbert space dimension d. these are the states, which can be written as linear combinations of permutation operators, or, equivalently, commute with unitaries of the form uxuxu. we compute explicitly the following subsets and their extreme points : ( 1 ) triseparable states, which are convex combinations of triple tensor products, ( 2 ) biseparable states, which are separable for a twofold partition of the system, and ( 3 ) states with positive partial transpose with respect to such a partition. tripartite entanglement is investigated in terms of the relative entropy of tripartite entanglement and of the trace norm.
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arxiv:quant-ph/0010096
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we present of measurements of radio emission from eas at the frequency 32 mhz performed in 2008 - 2012. showers were selected by zenith and azimuth directions, sampled by energy. a mean lateral distribution function was fitted to the data each interval. the paper presents unied approximation formula for all three energy intervals of lateral distribution, using connection between equation ( 1 ) and ( 2 ) coefficients with energy and geomagnetic angle. here we analyze the connection between the shape of lateral distribution and the depth of the maximum shower development xmax too.
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arxiv:1309.6698
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charge selective interlayers are crucial in thin - film photovoltaics, such as organic and perovskite solar cells. charge transporting layers ( doped and undoped ) constitute perhaps the most important class of charge selective interlayers ; however, it is not well understood how a charge transporting layer should be designed in order to ensure efficient extraction of majority carriers while blocking minority carriers. this work clarifies how well charge - transporting layers with varying majority carrier conductivities block minority carriers. we use the charge extraction by a linearly increasing voltage technique to determine the surface recombination velocity of minority carriers in model system devices with varying majority carrier conductivity in the transporting layer. our results show that transporting layers with high conductivity for majority carriers do not block minority carriers - at least not at operating voltages close to or above the built - in voltage, due to direct bi - molecular recombination across the transporting layer - absorber layer interface. we furthermore discuss and propose design principles to achieve selective charge extraction in thin film solar cells using charge transporting layers.
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arxiv:2201.03314
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kes 69 is a mixed - morphology ( mm ) supernova remnant ( snr ) that is known to be interacting with molecular clouds based on 1720 mhz hydroxyl ( oh ) maser emission observations in the northeastern and southeastern regions. we present an investigation of kes 69 using $ \ sim $ 67 ks suzaku observation. the x - ray spectrum of the whole snr is well fitted by a non - equilibrium ionization model with an electron temperature of $ kt _ { \ rm e } $ $ \ sim $ 2. 5 kev, ionization time - scale of $ \ tau $ $ \ sim $ 4. 1 $ \ times10 ^ { 10 } $ cm $ ^ { - 3 } $ s and absorbing column density of $ n _ { \ rm h } $ $ \ sim $ 3. 1 $ \ times10 ^ { 22 } $ cm $ ^ { - 2 } $. we clearly detected the fe - k $ \ alpha $ line at $ \ sim $ 6. 5 kev in the spectra. the plasma shows slightly enhanced abundances of mg, si, s and fe indicating that the plasma is likely to be of ejecta origin. we find no significant feature of a recombining plasma in this snr. in order to characterize radial variations in the x - ray spectral parameters, we also analyze annular regions in the remnant. we investigate the explosive origin of kes 69 and favor the core - collapse origin. additionally, we report a lack of significant gamma - ray emission from kes 69, after analyzing the gev gamma - ray data taken for about 9 years by the large area telescope on board fermi. finally, we discuss the properties of kes 69 in the context of other interacting mm snrs.
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arxiv:1808.10513
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starting from the orthorhombic magnetically ordered phase, we investigate the effects of uniaxial tensile and compressive stresses along a, b, and the diagonal a + b directions in bafe2as2 and cafe2as2 in the framework of ab initio density functional theory ( dft ) and a phenomonological ginzburg - landau model. while - contrary to the application of hydrostatic or c - axis uniaxial pressure - both systems remain in the orthorhombic phase with a pressure - dependent nonzero magnetic moment, we observe a sign - changing jump in the orthorhombicity at a critical uniaxial pressure, accompanied by a reversal of the orbital occupancy and a switch between the ferromagnetic and antiferromagnetic directions. our ginzburg - landau analysis reveals that this behavior is a direct consequence of the competition between the intrinsic magneto - elastic coupling of the system and the applied compressive stress, which helps the system to overcome the energy barrier between the two possible magneto - elastic ground states. our results shed light on the mechanisms involved in the detwinning process of an orthorhombic iron - pnictide crystal and on the changes in the magnetic properties of a system under uniaxial stress.
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arxiv:1210.5504
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determining the maximum number of edges under degree and matching number constraints have been solved for general graphs by chv \ ' { a } tal and hanson ( 1976 ), and by balachandran and khare ( 2009 ). it follows from the structure of those extremal graphs that deciding whether this maximum number decreases or not when restricted to claw - free graphs, to $ c _ 4 $ - free graphs or to triangle - free graphs are separately interesting research questions. the first two cases being already settled, respectively by dibek, ekim and heggernes ( 2017 ), and by blair, heggernes, lima and d. lokshtanov ( 2020 ). in this paper we focus on triangle - free graphs. we show that unlike most cases for claw - free graphs and $ c _ 4 $ - free graphs, forbidding triangles from extremal graphs causes a strict decrease in the number of edges and adds to the hardness of the problem. we provide a formula giving the maximum number of edges in a triangle - free graph with degree at most $ d $ and matching number at most $ m $ for all cases where $ d \ geq m $, and for the cases where $ d < m $ with either $ d \ leq 6 $ or $ z ( d ) \ leq m < 2d $ where $ z ( d ) $ is a function of $ d $ which is roughly $ 5d / 4 $. we also provide an integer programming formulation for the remaining cases and as a result of further discussion on this formulation, we conjecture that our formula giving the size of triangle - free extremal graphs is also valid for these open cases.
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arxiv:2207.02271
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a geometrical model for tri - nuclear molecules is presented. an analytical solution is obtained provided the nuclei, which are taken to be prolately deformed, are connected in line to each other. furthermore, the tri - nuclear molecule is composed of two heavy and one light cluster, the later sandwiched between the two heavy clusters. a basis is constructed in which hamiltonians of more general configurations can be diagonalized. in the calculation of the interaction between the clusters higher multipole deformations are taken into account, including the hexadecupole one. a repulsive nuclear core is introduced in the potential in order to insure a quasi - stable configuration of the system. the model is applied to three nuclear molecules, namely $ ^ { 96 } $ sr + $ ^ { 10 } $ be + $ ^ { 146 } $ ba, $ ^ { 108 } $ mo + $ ^ { 10 } $ be + $ ^ { 134 } $ te and $ ^ { 112 } $ ru + $ ^ { 10 } $ be + $ ^ { 130 } $ sn.
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arxiv:nucl-th/0010098
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media - processing applications, such as signal processing, 2d and 3d graphics rendering, and image compression, are the dominant workloads in many embedded systems today. the real - time constraints of those media applications have taxing demands on today ' s processor performances with low cost, low power and reduced design delay. to satisfy those challenges, a fast and efficient strategy consists in upgrading a low cost general purpose processor core. this approach is based on the personalization of a general risc processor core according the target multimedia application requirements. thus, if the extra cost is justified, the general purpose processor gpp core can be enforced with instruction level coprocessors, coarse grain dedicated hardware, ad hoc memories or new gpp cores. in this way the final design solution is tailored to the application requirements. the proposed approach is based on three main steps : the first one is the analysis of the targeted application using efficient metrics. the second step is the selection of the appropriate architecture template according to the first step results and recommendations. the third step is the architecture generation. this approach is experimented using various image and video algorithms showing its feasibility.
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arxiv:cs/0608075
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consider the parabolic anderson model $ \ partial _ tu = \ frac { 1 } { 2 } \ partial _ x ^ 2u + u \, \ eta $ on the interval $ [ 0, l ] $ with neumann, dirichlet or periodic boundary conditions, driven by space - time white noise $ \ eta $. using malliavin - stein method, we establish the central limit theorem for the fluctuation of the spatial integral $ \ int _ 0 ^ lu ( t \,, x ) \, \ mathrm { d } x $ as $ l $ tends to infinity, where the limiting gaussian distribution is independent of the choice of the boundary conditions and coincides with the gaussian fluctuation for the spatial average of parabolic anderson model on the whole space $ \ mathbb { r } $.
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arxiv:2008.08267
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let $ p $ be a prime number. mazur proved that a geometrically maximal unramified abelian covering of $ x _ 0 ( p ) $ over $ \ mathbb q $ is given by the shimura covering $ x _ 2 ( p ) \ to x _ 0 ( p ) $, that is, a unique subcovering of $ x _ 1 ( p ) \ to x _ 0 ( p ) $ of degree $ n _ p : = ( p - 1 ) / \ gcd ( p - 1, 12 ) $. in this short paper, we show that a geometrically maximal abelian covering $ x _ 2 ' ( p ) \ to x _ 0 ( p ) $ of $ x _ 0 ( p ) $ over $ \ mathbb q $ unramified outside cusps is cyclic of degree $ 2n _ p $. the main ingredient for the construction of $ x _ 2 ' ( p ) $ is the generalized dedelind eta functions.
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arxiv:1901.06564
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we investigate the sequence of great earthquakes over the past century. to examine whether the earthquake record includes temporal clustering, we identify aftershocks and remove those from the record. we focus on the recurrence time, defined as the time between two consecutive earthquakes. we study the variance in the recurrence time and the maximal recurrence time. using these quantities, we compare the earthquake record with sequences of random events, generated by numerical simulations, while systematically varying the minimal earthquake magnitude mmin. our analysis shows that the earthquake record is consistent with a random process for magnitude thresholds 7. 0 < = mmin < = 8. 3, where the number of events is larger. interestingly, the earthquake record deviates from a random process at magnitude threshold 8. 4 < = mmin < = 8. 5, where the number of events is smaller ; however, this deviation is not strong enough to conclude that great earthquakes are clustered. overall, the findings are robust both qualitatively and quantitatively as statistics of extreme values and moment analysis yield remarkably similar results.
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arxiv:1305.6967
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we investigate the seemingly ill - defined problem of extracting a ground - state mass from a lattice simulation where the extent of the lattice is not long enough to project out the ground - state properly. we regulate the problem using a bayesian method. we show that controlling meta - parameters ( overconfidence ) can allow the data to overcome the input priors ( bias ). we can write the method as a black - box technique which allows extraction of a ground - state mass, even on a relatively short lattice.
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arxiv:1910.11384
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