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in this article we investigate the structure of the non - local part of the symmetry term, that leads to a splitting of the effective masses of protons and neutrons in asymmetric matter. based on microscopic transport simulations we suggest some rather sensitive observables in collisions of neutron - rich ( unstable ) ions at intermediate ( $ ria $ ) energies. in particular we focus the attention on pre - equilibrium nucleon emissions. we discuss interesting correlations between the n / z content of the fast emitted particles and their rapidity or transverse momentum, that show a nice dependence on the prescription used for the effective mass splitting.
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arxiv:nucl-th/0508008
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the propagation of bound optical waves along the surface of a one - dimensional ( 1 - d ) photonic crystal ( pc ) structure is considered. a unified description of the waves in 1 - d pcs for both s - and p - polarizations is done via an impedance approach. a general dispersion relation that is valid for optical surface waves with both polarizations is obtained, and conditions are presented for long - range propagation of plasmon - polariton waves in nanofilms ( including lossy ones ) deposited on the top of the 1 - d pc structure. a method is described for designing 1 - d pc structures to fulfill the conditions required for the existence of the surface mode with a particular wavevector at a particular wavelength. it is shown that the propagation length of the long - range surface plasmon - polaritons can be maximized by wavelength tuning, which introduces a slight asymmetry in the system.
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arxiv:1005.2039
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non - identical two particle correlation functions probe asymmetries between the average space - time emission points of different particle species. the system collective expansion would produce such asymmetry because massive particles, such as protons, are on average more pushed towards the edge of the system, than lighter ones, i. e. pions. measuring pion - kaon, pion - proton and kaon - proton correlation functions, using the star detector, we show that the data are consistent with the effect of transverse flow in au - au collisions at $ \ sqrt { s _ { nn } } = 130 $ gev.
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arxiv:nucl-ex/0212026
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dense video captioning is the task that involves the detection and description of events within video sequences. while traditional approaches focus on offline solutions where the entire video of analysis is available for the captioning model, in this work we introduce a paradigm shift towards live video captioning ( lvc ). in lvc, dense video captioning models must generate captions for video streams in an online manner, facing important constraints such as having to work with partial observations of the video, the need for temporal anticipation and, of course, ensuring ideally a real - time response. in this work we formally introduce the novel problem of lvc and propose new evaluation metrics tailored for the online scenario, demonstrating their superiority over traditional metrics. we also propose an lvc model integrating deformable transformers and temporal filtering to address the lvc new challenges. experimental evaluations on the activitynet captions dataset validate the effectiveness of our approach, highlighting its performance in lvc compared to state - of - the - art offline methods. results of our model as well as an evaluation kit with the novel metrics integrated are made publicly available to encourage further research on lvc.
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arxiv:2406.14206
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a method is proposed to produce a classical optical state that is ` intersystem nonseparable ' and a close analog of the $ \ phi ^ + $ bell state. a derivation of the chsh - bell inequality is sketched within the framework of classical polarization optics, using non - contextuality for factorizable states as an axiom rather than any hidden variable theory. it is shown that the classical state violates this inequality.
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arxiv:2401.01615
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the plant microtubule cortical array is a striking feature of all growing plant cells. it consists of a more or less homogeneously distributed array of highly aligned microtubules connected to the inner side of the plasma membrane and oriented transversely to the cell growth axis. here we formulate a continuum model to describe the origin of orientational order in such confined arrays of dynamical microtubules. the model is based on recent experimental observations that show that a growing cortical microtubule can interact through angle dependent collisions with pre - existing microtubules that can lead either to co - alignment of the growth, retraction through catastrophe induction or crossing over the encountered microtubule. we identify a single control parameter, which is fully determined by the nucleation rate and intrinsic dynamics of individual microtubules. we solve the model analytically in the stationary isotropic phase, discuss the limits of stability of this isotropic phase, and explicitly solve for the ordered stationary states in a simplified version of the model.
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arxiv:0905.3288
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in this article, we propose and experimentally demonstrate a triple - mode single - transistor graphene amplifier utilizing a three - terminal back - gated single - layer graphene transistor. the ambipolar nature of electronic transport in graphene transistors leads to increased amplifier functionality as compared to amplifiers built with unipolar semiconductor devices. the ambipolar graphene transistors can be configured as n - type, p - type, or hybrid - type by changing the gate bias. as a result, the single - transistor graphene amplifier can operate in the common - source, common - drain, or frequency multiplication mode, respectively. this in - field controllability of the single - transistor graphene amplifier can be used to realize the modulation necessary for phase shift keying and frequency shift keying, which are widely used in wireless applications. it also offers new opportunities for designing analog circuits with simpler structure and higher integration densities for communications applications.
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arxiv:1010.1022
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large language models ( llms ) are increasingly being adopted in a wide range of real - world applications. despite their impressive performance, recent studies have shown that llms are vulnerable to deliberately crafted adversarial prompts even when aligned via reinforcement learning from human feedback or supervised fine - tuning. while existing defense methods focus on either detecting harmful prompts or reducing the likelihood of harmful responses through various means, defending llms against jailbreak attacks based on the inner mechanisms of llms remains largely unexplored. in this work, we investigate how llms response to harmful prompts and propose a novel defense method termed \ textbf { l } ayer - specific \ textbf { ed } iting ( led ) to enhance the resilience of llms against jailbreak attacks. through led, we reveal that several critical \ textit { safety layers } exist among the early layers of llms. we then show that realigning these safety layers ( and some selected additional layers ) with the decoded safe response from selected target layers can significantly improve the alignment of llms against jailbreak attacks. extensive experiments across various llms ( e. g., llama2, mistral ) show the effectiveness of led, which effectively defends against jailbreak attacks while maintaining performance on benign prompts. our code is available at \ url { https : / / github. com / ledllm / ledllm }.
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arxiv:2405.18166
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affinity has proven to be a useful tool for quantifying the non - equilibrium character of time continuous markov processes since it serves as a measure for the breaking of time reversal symmetry. it has recently been conjectured that the number of coherent oscillations, which is given by the ratio of imaginary and real part of the first non - trivial eigenvalue of the corresponding master matrix, is constrained by the maximum cycle affinity present in the network. in this paper, we conjecture a bound on the whole spectrum of these master matrices that constrains all eigenvalues in a fashion similar to the well known perron - frobenius theorem that is valid for any stochastic matrix. as in other studies that are based on affinity - dependent bounds, the limiting process that saturates the bound is given by the asymmetric random walk. for unicyclic networks, we prove that it is not possible to violate the bound by small perturbation of the asymmetric random walk and provide numerical evidence for its validity in randomly generated networks. the results are extended to multicyclic networks, backed up by numerical evidence provided by networks with randomly constructed topology and transition rates.
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arxiv:1907.04260
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discussion of ` ` the william kruskal legacy : 1919 - - 2005 ' ' by stephen e. fienberg, stephen m. stigler and judith m. tanur [ arxiv : 0710. 5063 ]
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arxiv:0710.5079
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we are concerned with the calder \ ' on problem of determining an unknown conductivity of a body from the associated boundary measurement. we establish a logarithmic type stability estimate in terms of the hausdorff distance in determining the support of a convex polygonal inclusion by a single partial boundary measurement. we also derive the uniqueness result in a more general scenario where the conductivities are piecewise constants supported in a nested polygonal geometry. our methods in establishing the stability and uniqueness results have a significant technical initiative and a strong potential to apply to other inverse boundary value problems.
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arxiv:1902.04462
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we present a new chemodynamical code based on the adaptive mesh refinement code ramses. the new code uses eulerian hydrodynamics and n - body dynamics in a cosmological framework to trace the production and advection of several chemical species. it is the first such code to follow the self - consistent evolution of chemical elements in cosmological volumes while maintaining sub - kiloparsec resolution. the code will be used to simulate disk galaxies and explore the influence of chemical evolution models and star formation on galactic abundance ratios.
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arxiv:1202.2120
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moir \ ' e superlattices of van der waals heterostructures provide a powerful new way to engineer the electronic structures of two - dimensional ( 2d ) materials. many novel quantum phenomena have emerged in different moir \ ' e heterostructures, such as correlated insulators, superconductors, and chern insulators in graphene systems and moir \ ' e excitons in transition metal dichalcogenide ( tmdc ) systems. twisted phosphorene offers another attractive system to explore moir \ ' e physics because phosphorene features an anisotropic rectangular lattice, different from the isotropic hexagonal lattice in graphene and tmdc. here we report emerging anisotropic moir \ ' e optical transitions in twisted monolayer / bilayer phosphorene. the optical resonances in phosphorene moir \ ' e superlattice depend sensitively on the twist angle between the monolayer and bilayer. surprisingly, even for a twist angle as large as 19 { \ deg } the moir \ ' e heterostructure exhibits optical resonances completely different from those in the constituent monolayer and bilayer phosphorene. the new moir \ ' e optical resonances exhibit strong linear polarization, with the principal axis lying close to but different from the optical axis of bilayer phosphorene. our ab initio calculations reveal that the { \ gamma } - point direct bandgap and the rectangular lattice of phosphorene, unlike the k - point bandgap of hexagonal lattice in graphene and tmdc, give rise to the remarkably strong moir \ ' e physics in large - twist - angle phosphorene heterostructures. our results highlight the exciting opportunities to explore moir \ ' e physics in phosphorene and other van der waals heterostructures with different lattice configurations.
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arxiv:1912.03644
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we build systems of imprimitivity ( si ) in the context of quantum walks and provide geometric constructions for their configuration space. we consider three systems, an evolution of unitaries from the group so3 on a low dimensional de sitter space where the walk happens on the dual of so3, standard quantum walk whose si live on the orbits of stabilizer subgroups ( little groups ) of semidirect products describing the symmetries of 1 + 1 spacetime, and automorphisms ( walks are specific automorphisms ) on distant - transitive graphs as application of the constructions.
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arxiv:1803.07049
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in statistical modeling area, the akaike information criterion aic, is a widely known and extensively used tool for model choice. the { \ phi } - divergence test statistic is a recently developed tool for statistical model selection. the popularity of the divergence criterion is however tempered by their known lack of robustness in small sample. in this paper the penalized minimum hellinger distance type statistics are considered and some properties are established. the limit laws of the estimates and test statistics are given under both the null and the alternative hypotheses, and approximations of the power functions are deduced. a model selection criterion relative to these divergence measures are developed for parametric inference. our interest is in the problem to testing for choosing between two models using some informational type statistics, when independent sample are drawn from a discrete population. here, we discuss the asymptotic properties and the performance of new procedure tests and investigate their small sample behavior.
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arxiv:1110.3151
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we consider a specialization $ y _ m ( q, t ) $ of the tutte polynomial of a matroid $ m $ which is inspired by analogy with the potts model from statistical mechanics. the only information lost in this specialization is the number of loops of $ m $. we show that the coefficients of $ y _ m ( 1 - p, t ) $ are very simply related to the ranks of the whitney homology groups of the opposite partial orders of the independent set complexes of the duals of the truncations of $ m $. in particular, we obtain a new homological interpretation for the coefficients of the characteristic polynomial of a matroid.
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arxiv:math/9702219
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we present the first attempt at measuring the baryonic acoustic oscillations ( bao ) in the large scale cross - correlation between the magnesium - ii doublet ( mgii ) flux transmission field and the position of quasar and galaxy tracers. the mgii flux transmission continuous field at $ 0. 3 < z < 1. 6 $ is measured from 500, 589 quasar spectra obtained in the baryonic oscillation spectroscopic survey ( boss ) and the extended boss ( eboss ). the position of 246, 697 quasar tracers and 1, 346, 776 galaxy tracers are extracted from the sloan digital sky survey ( sdss ) i, ii, boss and eboss catalogs. in addition to measuring the cosmological bao scale and the biased matter density correlation, this study allows tests and improvements to cosmological lyman - $ \ alpha $ analyses. a feature consistent with that of the bao is detected at a significance of $ \ delta \ chi ^ { 2 } = 7. 25 $. the measured mgii linear transmission bias parameters are $ b _ { \ mathrm { mgii ( 2796 ) } } ( z = 0. 59 ) = ( - 6. 82 \ pm 0. 54 ) \, \ times 10 ^ { - 4 } $ and $ b _ { \ mathrm { mgii ( 2804 ) } } ( z = 0. 59 ) = ( - 5. 55 \ pm 0. 46 ) \, \ times 10 ^ { - 4 } $, and the mgi bias is $ b _ { \ mathrm { mgi ( 2853 ) } } ( z = 0. 59 ) = ( - 1. 48 \ pm 0. 24 ) \, \ times 10 ^ { - 4 } $. their redshift evolution is characterized by the power - law index : $ \ gamma _ { \ mathrm { mg } } = 3. 36 \ pm 0. 46 $. these measurements open a new window towards using bao from flux transmission at $ z < 1 $ in the final eboss sample and in the upcoming sample from the dark energy spectroscopic instrument.
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arxiv:1901.01950
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with the growing reliance on the ubiquitous availability of it systems and services, these systems become more global, scaled, and complex to operate. to maintain business viability, it service providers must put in place reliable and cost efficient operations support. artificial intelligence for it operations ( aiops ) is a promising technology for alleviating operational complexity of it systems and services. aiops platforms utilize big data, machine learning and other advanced analytics technologies to enhance it operations with proactive actionable dynamic insight. in this paper we share our experience applying the aiops approach to a production cloud object storage service to get actionable insights into system ' s behavior and health. we describe a real - life production cloud scale service and its operational data, present the aiops platform we have created, and show how it has helped us resolving operational pain points.
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arxiv:2005.03094
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in this paper, we consider a time - periodically forced kepler problem in any dimensions, with an external force which we only assume to be regular in a neighborhood of the attractive center. we prove that there exist infinitely many periodic orbits in this system, with possible double collisions with the center regularized, which accumulate the attractive center. the result is obtained via a localization argument combined with a result on $ c ^ { 1 } $ - persistence of closed orbits by a local homotopy - streching argument. consequently, by formulating the circular and elliptic restricted three - body problems of any dimensions as time - periodically forced kepler problems, we obtain that there exists infinitely many periodic orbits, with possible double collisions with the primaries regularized, accumulating to each of the primaries.
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arxiv:2010.15253
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we revisit here a recent work on regular rotating black holes. we introduce a new mass function generalizing the commonly used bardeen and hayward mass functions and extend the recently proposed solutions in order to accommodate a cosmological constant $ \ lambda $. we discuss some aspects of the causal structure ( horizons ) and the ergospheres of the new proposed solutions. we also show that, in contrast with the spherically symmetrical case, the black hole rotation will unavoidably lead to the violation of the weak energy condition for any physically reasonable choice of the mass function, reinforcing the idea the description of the interior region of a kerr black hole is much more challenging than in the schwarzschild case.
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arxiv:1402.2694
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the recently - developed wavenet architecture is the current state of the art in realistic speech synthesis, consistently rated as more natural sounding for many different languages than any previous system. however, because wavenet relies on sequential generation of one audio sample at a time, it is poorly suited to today ' s massively parallel computers, and therefore hard to deploy in a real - time production setting. this paper introduces probability density distillation, a new method for training a parallel feed - forward network from a trained wavenet with no significant difference in quality. the resulting system is capable of generating high - fidelity speech samples at more than 20 times faster than real - time, and is deployed online by google assistant, including serving multiple english and japanese voices.
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arxiv:1711.10433
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a search for pair production of the lightest supersymmetric partner of the top quark is performed in the lepton + jets channel using 0. 9 fb - 1 of data collected by the d0 experiment. kinematic differences between scalar top quark pair production and the dominant top quark pair production background are used to separate the two processes. first limits from run ii of the fermilab tevatron collider for the scalar top quark decaying to a chargino and a b quark are obtained for scalar top quark masses of 130 - 190 gev and chargino masses of 90 - 150 gev.
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arxiv:0901.1063
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in this work we investigate the interplay between gravity and turbulence at different spatial scales and in different density regimes. we analyze a sample of 70 $ \ mu $ m quiet clumps that are divided into three surface density bins and we compare the dynamics of each group with the dynamics of their respective filaments. the densest clumps form within the densest filaments on average, and they have the highest value of the velocity dispersion. the kinetic energy is transferred from the filaments down to the clumps most likely through a turbulent cascade, but we identify a critical value of the surface density, $ \ sigma \ simeq0. 1 $ g cm $ ^ { 2 } $, above which the dynamics changes from being mostly turbulent - driven to mostly gravity - driven. the scenario we obtain from our data is a continuous interplay between turbulence and gravity, where the former creates structures at all scales and the latter takes the lead when the critical surface density threshold is reached. in the densest filaments this transition can occur at the parsec, or even larger scales, leading to a global collapse of the whole region and most likely to the formation of the massive objects.
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arxiv:1912.00031
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we present a mechanism to generate unidirectional pulse - shaped propagating waves, tamed to exponential growth and dispersion, in active systems with nonreciprocal and nonlinear couplings. in particular, when all bulk modes are exponentially localized at one side of the lattice ( skin effect ), it is expected that wave dynamics is governed by amplification or decay until reaching the boundaries, even in the presence of dissipation. our analytical results, and experimental demonstrations in an active electrical transmission line metamaterial, reveal that nonlinearity is a crucial tuning parameter in mediating a delicate interplay between nonreciprocity, dispersion, and dissipation. consequently, undistorted unidirectional solitonic pulses are supported both for low and high nonreciprocity and pulse amplitude strength. the proposed mechanism facilitates robust pulse propagation in signal processing and energy transmission applications.
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arxiv:2502.16216
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how do we bridge the gap between the galactic and the extragalactic? by focusing on the topic of stellar dynamics and stellar populations of the milky way and its siblings this virtual meeting aimed at connecting both fields that each bring unique perspectives to understanding how disk galaxies form and evolve. as this meeting took place during a global pandemic, we also give our perspective on the challenges and best practises for running a virtual meeting.
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arxiv:2107.11531
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we present a robust method to find region - level correspondences between shapes, which are invariant to changes in geometry and applicable across multiple shape representations. we generate simplified shape graphs by jointly decomposing the shapes, and devise an adapted graph - matching technique, from which we infer correspondences between shape regions. the simplified shape graphs are designed to primarily capture the overall structure of the shapes, without reflecting precise information about the geometry of each region, which enables us to find correspondences between shapes that might have significant geometric differences. moreover, due to the special care we take to ensure the robustness of each part of our pipeline, our method can find correspondences between shapes with different representations, such as triangular meshes and point clouds. we demonstrate that the region - wise matching that we obtain can be used to find correspondences between feature points, reveal the intrinsic self - similarities of each shape, and even construct point - to - point maps across shapes. our method is both time and space efficient, leading to a pipeline that is significantly faster than comparable approaches. we demonstrate the performance of our approach through an extensive quantitative and qualitative evaluation on several benchmarks where we achieve comparable or superior performance to existing methods.
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arxiv:1710.05592
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some of the major limitations identified in the areas of argument mining, argument generation, and natural language argument analysis are related to the complexity of annotating argumentatively rich data, the limited size of these corpora, and the constraints that represent the different languages and domains in which these data is annotated. to address these limitations, in this paper we present the following contributions : ( i ) an effective methodology for the automatic generation of natural language arguments in different topics and languages, ( ii ) the largest publicly available corpus of natural language argumentation schemes, and ( iii ) a set of solid baselines and fine - tuned models for the automatic identification of argumentation schemes.
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arxiv:2402.14458
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the horndeski scalar - tensor theory and its recent extensions allow nonlinear derivative interactions of the scalar degree of freedom. we study the matter bispectrum of large scale structure as a probe of these modified gravity theories, focusing in particular on the effect of the terms that newly appear in the so - called " beyond horndeski " theories. we derive the second - order solution for the matter density perturbations and find that the interactions beyond horndeski lead to a new time - dependent coefficient in the second - order kernel which differs in general from the standard value of general relativity and the horndeski theory. this can deform the matter bispectrum at the folded triangle configurations ( $ k _ 1 + k _ 2 = k _ 3 $ ), while it is never possible within the horndeski theory.
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arxiv:1801.07885
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in practical scenarios involving the measurement of surface electromyography ( semg ) in muscles, particularly those areas near the heart, one of the primary sources of contamination is the presence of electrocardiogram ( ecg ) signals. to assess the quality of real - world semg data more effectively, this study proposes qase - net, a new non - intrusive model that predicts the snr of semg signals. qase - net combines cnn - blstm with attention mechanisms and follows an end - to - end training strategy. our experimental framework utilizes real - world semg and ecg data from two open - access databases, the non - invasive adaptive prosthetics database and the mit - bih normal sinus rhythm database, respectively. the experimental results demonstrate the superiority of qase - net over the previous assessment model, exhibiting significantly reduced prediction errors and notably higher linear correlations with the ground truth. these findings show the potential of qase - net to substantially enhance the reliability and precision of semg quality assessment in practical applications.
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arxiv:2402.05482
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we analyze the thermal magnetization reversal processes in magnetic grains. two experiments are carried out : swtiching time and switching field experiments. in both cases, we find that the simulated behavior is coherent with existing experimental data ( the streched exponent of the switching time experiment increases with the temperature and is superior to unity ; there exists a master curve for the switching field experiment ). moreover, we simulated magnetic grains in a region of parameters where no experimental data are available. we find that the relaxation time distribution $ p ( \ ln { \ tau } ) $ is gaussian, and we find the existence of a strong field regime.
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arxiv:cond-mat/9603026
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networks are ubiquitous throughout science and engineering. a number of methods, including some from our own group, have explored how one goes about computing or predicting the dynamics of networks given information about internal models of individual nodes and network connectivity, possibly with additional information provided by statistical or descriptive metrics that characterize the network. but what can be inferred about network dynamics when there is no knowledge or information about the internal model or dynamics of participating nodes? here, we explore how connected subsets of nodes competitively interact in order to activate a common downstream node they connect into. we achieve this by assuming a simple set of rules borrowed from neurophysiology. the model we develop reflects a local process from which global network dynamics emerges. we call this model a competitive refractory dynanics model. it is derived from a consideration of spatial and temporal summation in biological neurons, whereby summating post synaptic potentials ( psps ) along the dendritic tree contribute towards the membrane potential at the initial segment reaching a threshold potential. we first show how the ' winning node ' or set of ' winning ' nodes that achieve activation of a downstream node is computable by the model. we then derive a formal definition of optimized network signaling within our framework. we define a ratio between the signaling latencies on the edges of the network and the internal time it takes individual nodes to process incoming signals. we show that an optimal ratio is one where the speed of information propagation between connected nodes does not exceed the internal dynamic time scale of the nodes. we then show how we can use these results to arrive at a unique interpretation for the prevalence of the small world network topology in natural and engineered systems.
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arxiv:1510.08729
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we present initial results from the polarisation sky survey of the universe ' s magnetism ( possum ), analysing 22, 817 faraday rotation measures ( rms ) with median uncertainties of 1. 2 rad m ^ - 2 across 1, 520 square degrees to study magnetised gas associated with 55 nearby galaxy groups ( z less than 0. 025 ) with halo masses between 10 ^ 12. 5 and 10 ^ 14. 0 m _ sun. we identify two distinct gas phases : the intragroup medium ( igrm ) within 0 - 2 splashback radii and the warm - hot intergalactic medium ( whim ) extending from 2 to 7 splashback radii. these phases enhance the standard deviation of residual ( i. e., galactic foreground rm - subtracted ) rms by 6. 9 + / - 1. 8 rad m ^ - 2 and 4. 2 + / - 1. 2 rad m ^ - 2, respectively. estimated magnetic field strengths are several microgauss within the igrm and 0. 1 - 1 microgauss in the whim. we estimate the plasma beta in both phases and show that magnetic pressure might be more dynamically important than in the icm of more massive clusters or sparse cosmic web filaments. our findings indicate that " missing baryons " in the whim likely extend beyond the gravitational radii of group - mass halos to mpc scales, consistent with large - scale, outflow - driven " magnetised bubbles " seen in cosmological simulations. we demonstrate that rm grids are an effective method for detecting magnetised thermal gas at galaxy group interfaces and within the cosmic web. this approach complements x - ray and sunyaev - zel ' dovich effect methods, and when combined with fast radio burst dispersion measures, data from the full possum survey, comprising approximately a million rms, will allow direct magnetic field measurements to further our understanding of baryon circulation in these environments and the magnetised universe.
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arxiv:2407.20325
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in this article we report on the experimental realization of dimensional crossover phenomena in the chain compound prba $ _ 2 $ cu $ _ 4 $ o $ _ 8 $ using temperature, high magnetic fields and disorder as independent tuning parameters. in purer crystals of prba $ _ 2 $ cu $ _ 4 $ o $ _ 8 $, a highly anisotropic three - dimensional fermi - liquid state develops at low temperatures. this metallic state is extremely susceptible to disorder however and localization rapidly sets in. we show, through quantitative comparison of the relevant energy scales, that this metal / insulator crossover occurs precisely when the scattering rate within the chain exceeds the interchain hopping rate ( s ), i. e. once carriers become confined to a single conducting element.
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arxiv:0708.3860
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the rapid digitalization of communication systems has elevated interactive voice response ( ivr ) technologies to become critical interfaces for customer engagement. with artificial intelligence ( ai ) now driving these platforms, ensuring secure, compliant, and ethically designed development practices is more imperative than ever. ai - powered ivrs leverage natural language processing ( nlp ) and machine learning ( ml ) to personalize interactions, automate service delivery, and optimize user experiences. however, these innovations expose systems to heightened risks, including data privacy breaches, ai decision opacity, and model security vulnerabilities. this paper analyzes the evolution of ivrs from static code - based designs to adaptive ai - driven systems, presenting a cybersecurity - centric perspective. we propose a practical governance framework that embeds agile security principles, compliance with global data legislation, and user - centric ethics. emphasizing privacy - by - design, adaptive risk modeling, and transparency, the paper argues that ethical ai integration is not a feature but a strategic imperative. through this multidimensional lens, we highlight how modern ivrs can transition from communication tools to intelligent, secure, and accountable digital frontlines - resilient against emerging threats and aligned with societal expectations.
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arxiv:2505.01514
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the \ d0 ( dzero ) detector at fermilab is currently collecting data since march 1, 2001, called run 2. the detector has undergone an extensive upgrade to participate in the run 2 data taking. the design of the detector meets the requirements of the high luminosity environment provided by the accelerator. this paper describes the upgraded detector subsystems and gives an outline of the physics potentials associated with the upgrade.
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arxiv:hep-ex/0202047
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the field of plasma - based particle accelerators has seen tremendous progress over the past decade and experienced significant growth in the number of activities. during this process, the involved scientific community has expanded from traditional university - based research and is now encompassing many large research laboratories worldwide, such as bnl, cern, desy, kek, lbnl and slac. as a consequence, there is a strong demand for a consolidated effort in education at the intersection of accelerator, laser and plasma physics. the cern accelerator school on plasma wake acceleration has been organized as a result of this development. in this paper, we describe the interactive component of this one - week school, which consisted of three case studies to be solved in 11 working groups by the participants of the cern accelerator school.
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arxiv:1705.11094
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a characterization of congruences in free semigroups is presented.
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arxiv:0810.3196
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we offer a new proof that two closed oriented 4 - manifolds are cobordant if their signatures agree, in the spirit of lickorish ' s proof that all closed oriented 3 - manifolds bound 4 - manifolds. where lickorish uses heegaard splittings we use trisections. in fact we begin with a subtle recasting of lickorish ' s argument : instead of factoring the gluing map for a heegaard splitting as a product of dehn twists, we encode each handlebody in a heegaard splitting in terms of a morse function on the surface and build the 4 - manifold from a generic homotopy between the two functions. this extends up a dimension by encoding a trisection of a closed 4 - manifold as a triangle ( circle ) of functions and constructing an associated 5 - manifold from an extension to a 2 - simplex ( disk ) of functions. this borrows ideas from hatcher and thurston ' s proof that the mapping class group of a surface is finitely presented.
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arxiv:1701.01711
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we propose a novel distributed resource allocation scheme for the up - link of a cellular multi - carrier system based on the message passing ( mp ) algorithm. in the proposed approach each transmitter iteratively sends and receives information messages to / from the base station with the goal of achieving an optimal resource allocation strategy. the exchanged messages are the solution of small distributed allocation problems. to reduce the computational load, the mp problems at the terminals follow a dynamic programming formulation. the advantage of the proposed scheme is that it distributes the computational effort among all the transmitters in the cell and it does not require the presence of a central controller that takes all the decisions. numerical results show that the proposed approach is an excellent solution to the resource allocation problem for cellular multi - carrier systems.
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arxiv:0810.4442
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the $ ^ { 13 } c $ substitutions of molecule $ hc _ 7n $ were observed in tmc - 1 using the j = 12 - 11, j = 13 - 12 rotational transitions in the frequency range 12. 4 to 13. 6 ghz. we present the first detection the $ ^ { 13 } c $ isotopic species of $ hc _ 7n $ in the interstellar medium, based on the average of a number of weak rotational transitions. this paper describes the calibration and data averaging process that is also used in a search for large cyanopolyyne molecules in tmc - 1 using the 100m robert c. byrd green bank telescope ( gbt ). the capabilities of the gbt 11 to 15 ghz observing system are described along with a discussion of numerical methods for averaging observations of a number of weak spectral lines to detect new interstellar molecules.
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arxiv:astro-ph/0612602
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this work validates a dynamic production network model, used to quantify the impact of economic shocks caused by covid - 19 in the uk, using data for belgium. because the model was published early during the 2020 covid - 19 pandemic, it relied on several assumptions regarding the magnitude of the observed economic shocks, for which more accurate data have become available in the meantime. we refined the propagated shocks to align with observed data collected during the pandemic and calibrated some less well - informed parameters using 115 economic time series. the refined model effectively captures the evolution of gdp, revenue, and employment during the covid - 19 pandemic in belgium at both individual economic activity and aggregate levels. however, the reduction in business - to - business demand is overestimated, revealing structural shortcomings in accounting for businesses ' motivations to sustain trade despite the pandemic ' s induced shocks. we confirm that the relaxation of the stringent leontief production function by a survey on the criticality of inputs significantly improved the model ' s accuracy. however, despite a large dataset, distinguishing between varying degrees of relaxation proved challenging. overall, this work demonstrates the model ' s validity in assessing the impact of economic shocks caused by an epidemic in belgium.
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arxiv:2305.16377
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magnetometry measurements in high quality lifeas single - crystals reveal a change in the sign of the magnetic hysteresis in the vicinity of the upper critical field $ h _ { c2 } $, from a clear diamagnetic response dominated by the pinning of vortices, to a considerably smaller net hysteretic response of opposite sign, which \ emph { disappears } at $ h _ { c2 } $. if the diamagnetic response at high fields results from pinned vortices and associated screening super - currents, this sign change must result from currents circulating in the opposite sense, which give rise to a small field - dependent magnetic moment \ emph { below } $ h _ { c2 } $. this behavior seems to be extremely sensitive to the sample quality or stoichiometry, as we have observed it only in a few fresh crystals, which also display the de haas van alphen - effect. we provide arguments against the surface superconductivity, the flux compression, and the random $ \ pi $ junction scenarios, which have been previously put forward to explain a paramagnetic meissner effect, below the lower critical field $ h _ { c1 } $. the observed anomalous hysteresis at high fields will be compatible with the existence of chiral gap wave - functions, which possess a field dependent magnetic moment. within a landau - ginzburg framework, we demonstrate how a $ ( d _ { x ^ 2 - y ^ 2 } + id _ { xy } ) $ or a $ ( p _ x + ip _ y ) $ chiral superconducting component can be stabilized in the mixed state of $ s _ { \ pm } $ superconductor, due to the combined effects of the magnetic field and the presence of competing pairing channels. the realization of a particular chiral pairing depends on the microscopic details of the strengths of the competing pairing channels.
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arxiv:1208.4882
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left - right symmetric models with general $ g _ l \ neq g _ r $ gauge couplings which include bidoublet and triplet scalar multiplets are studied. possible scalar mass spectra are outlined by imposing tree - unitarity, and vacuum stability criteria and also using the bounds on neutral scalar masses $ m _ { \ rm h ^ { fcnc } } $ which assure the absence of flavour changing neutral currents ( fcnc ). we are focusing on mass spectra relevant for the lhc analysis, i. e., the scalar masses are around tev scale. as all non - standard heavy particle masses are related to the vacuum expectation value ( vev ) of the right - handed triplet ( $ v _ r $ ), the combined effects of relevant higgs potential parameters and $ m _ { \ rm h ^ { fcnc } } $ regulate the lower limits of heavy gauge boson masses. the complete set of renormalization group evolutions for all couplings are provided at the 1 - loop level, including the mixing effects in the yukawa sector. most of the scalar couplings suffer from the landau poles at the intermediate scale $ q \ sim 10 ^ { 6. 5 } $ gev, which in general coincides with violation of the tree - unitarity bounds.
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arxiv:1604.06987
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we introduce an algebraic theory of integration on quantum planes and other braided spaces. in the one dimensional case we obtain a novel picture of the jackson $ q $ - integral as indefinite integration on the braided group of functions in one variable $ x $. here $ x $ is treated with braid statistics $ q $ rather than the usual bosonic or grassmann ones. we show that the definite integral $ \ int x $ can also be evaluated algebraically as multiples of the integral of a $ q $ - gaussian, with $ x $ remaining as a bosonic scaling variable associated with the $ q $ - deformation. further composing our algebraic integration with a representation then leads to ordinary numbers for the integral. we also use our integration to develop a full theory of $ q $ - fourier transformation $ f $. we use the braided addition $ \ delta x = x \ otimes 1 + 1 \ otimes x $ and braided - antipode $ s $ to define a convolution product, and prove a convolution theorem. we prove also that $ f ^ 2 = s $. we prove the analogous results on any braided group, including integration and fourier transformation on quantum planes associated to general r - matrices, including $ q $ - euclidean and $ q $ - minkowski spaces.
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arxiv:hep-th/9402037
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novel superhard materials, especially those with superior thermal and chemical stability, are needed to replace diamond. carbon nitrides ( c - n ), which are likely to possess these charac - teristics and have even been expected to be harder than diamond, are excellent candidates. here we report three new superhard and thermodynamically stable carbon nitride phases. based on a systematic evolutionary structure searches, we report a complete phase diagram of the c - n system at 0 - 300 gpa and analyze the hardest metastable structures. surprising - ly, we find that at zero pressure, the earlier proposed graphitic - c3n4 structure ( p - 6m2 ) is dynamically unstable and the lowest energy form of structures based on s - triazine unit and s - heptazine unit have similar topology and belong to the same space group.
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arxiv:1408.2901
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the harmonic dirichlet space $ \ cal { d } ( \ mathbb { t } ) $ is the hilbert space of functions $ f \ in l ^ 2 ( \ mathbb { t } ) $ such that $ $ \ | f \ | _ { \ cal { d } ( \ mathbb { t } ) } ^ 2 : = \ sum _ { n \ in \ mathbb { z } } ( 1 + | n | ) | \ hat { f } ( n ) | ^ 2 < \ infty. $ $ we give sufficient conditions for $ f $ to be cyclic in $ \ cal { d } ( \ mathbb { t } ) $, in other words, for $ \ { \ zeta ^ nf ( \ zeta ) : \ n \ geq 0 \ } $ to span a dense subspace of $ \ cal { d } ( \ mathbb { t } ) $.
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arxiv:1601.06572
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cryo - electron tomography ( cryo - et ) is an emerging technology for the 3d visualization of structural organizations and interactions of subcellular components at near - native state and sub - molecular resolution. tomograms captured by cryo - et contain heterogeneous structures representing the complex and dynamic subcellular environment. since the structures are not purified or fluorescently labeled, the spatial organization and interaction between both the known and unknown structures can be studied in their native environment. the rapid advances of cryo - electron tomography ( cryo - et ) have generated abundant 3d cellular imaging data. however, the systematic localization, identification, segmentation, and structural recovery of the subcellular components require efficient and accurate large - scale image analysis methods. we introduce aitom, an open - source artificial intelligence platform for cryo - et researchers. aitom provides many public as well as in - house algorithms for performing cryo - et data analysis through both the traditional template - based or template - free approach and the deep learning approach. aitom also supports remote interactive analysis. comprehensive tutorials for each analysis module are provided to guide the user through. we welcome researchers and developers to join this collaborative open - source software development project. availability : https : / / github. com / xulabs / aitom
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arxiv:1911.03044
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it is the responsibility of today ' s scientists, engineers, and educators to inspire and encourage our youth into technical careers that benefit our society. too often, however, this responsibility is buried beneath daily job demands and the routines of teaching. space public outreach team ( spot ) programs leverage a train - the - trainer model to empower college students to make meaningful impacts in their local communities by engaging and inspiring younger students through science presentations. spot takes advantage of the excitement of space and the natural way college students serve as role models for children. the result is a win - win program for all involved. this paper describes the original montana spot program, presents analyses demonstrating the success of spot, gives overviews of program adaptations in west virginia and with the nanograv collaboration, describes how college student presenters are able to share complex topics, and discusses the importance of college student role models. we hope that our experiences with spot will help others implement similar strategies in their own communities.
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arxiv:2010.15911
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principal manifolds serve as useful tool for many practical applications. these manifolds are defined as lines or surfaces passing through " the middle " of data distribution. we propose an algorithm for fast construction of grid approximations of principal manifolds with given topology. it is based on analogy of principal manifold and elastic membrane. the first advantage of this method is a form of the functional to be minimized which becomes quadratic at the step of the vertices position refinement. this makes the algorithm very effective, especially for parallel implementations. another advantage is that the same algorithmic kernel is applied to construct principal manifolds of different dimensions and topologies. we demonstrate how flexibility of the approach allows numerous adaptive strategies like principal graph constructing, etc. the algorithm is implemented as a c + + package elmap and as a part of stand - alone data visualization tool vidaexpert, available on the web. we describe the approach and provide several examples of its application with speed performance characteristics.
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arxiv:cond-mat/0405648
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we investigate the complexity = volume proposal in the case of janus ads $ _ 3 $ geometries, both at zero and finite temperature. the leading contribution coming from the janus interface is a logarithmic divergence, whose coefficient is a function of the dilaton excursion. in the presence of the defect, complexity is no longer topological and becomes temperature - dependent. we also study the time evolution of the extremal volume for the time - dependent janus btz black hole. this background is not dual to an interface but to a pair of entangled cfts with different values of the couplings. at late times, when the equilibrium is restored, the couplings of the cfts do not influence the complexity rate. on the contrary, the complexity rate for the out - of - equilibrium system is always smaller compared to the pure btz black hole background.
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arxiv:2105.08729
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in this paper we calculate the position and momentum space information entropies for the quantum states associated with a particular physical system, i. e. the isotonic oscillator hamiltonian. we present our results for its ground states, as well as for its excited states. we observe that the lower bound of the sum of the position and momentum entropies expressed by the beckner, bialynicki - birula and mycielski ( bbm ) inequality is satisfied. moreover, there exist eigenstates that exhibit squeezing in the position information entropy. in fact, entropy squeezing, which occurs in position, will be compensated for by an increase in momentum entropy, such that the bbm inequality is guaranteed. to complete our study we investigate the amplitude squeezing in $ x $ and $ p $ - quadratures corresponding to the eigenstates of the isotonic oscillator and show that amplitude squeezing, again in $ x $, will be revealed as expected, while the heisenberg uncertainty relationship is also satisfied. finally, our numerical calculations of the entropy densities will be presented graphically.
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arxiv:1108.5727
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we calculate one loop corrections to the domain - wall quark propagator in qcd. we show how the wave function is renormalized in this theory. especially we are interested in the behavior of the massless fermion mode, which exists near the domain wall at the tree level. we show that this massless mode is stable against the quantum correction.
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arxiv:hep-lat/9709123
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compared to natural images, medical images usually show stronger visual patterns and therefore this adds flexibility and elasticity to resource - limited clinical applications by injecting proper priors into neural networks. in this paper, we propose spatially covariant pixel - aligned classifier ( scp ) to improve the computational efficiency and meantime maintain or increase accuracy for lesion segmentation. scp relaxes the spatial invariance constraint imposed by convolutional operations and optimizes an underlying implicit function that maps image coordinates to network weights, the parameters of which are obtained along with the backbone network training and later used for generating network weights to capture spatially covariant contextual information. we demonstrate the effectiveness and efficiency of the proposed scp using two lesion segmentation tasks from different imaging modalities : white matter hyperintensity segmentation in magnetic resonance imaging and liver tumor segmentation in contrast - enhanced abdominal computerized tomography. the network using scp has achieved 23. 8 %, 64. 9 % and 74. 7 % reduction in gpu memory usage, flops, and network size with similar or better accuracy for lesion segmentation.
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arxiv:2301.07895
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this paper explores some important aspects of the theory of rearrangement - invariant quasi - banach function spaces. we focus on two main topics. firstly, we prove an analogue of the luxemburg representation theorem for rearrangement - invariant quasi - banach function spaces over resonant measure spaces. secondly, we develop the theory of fundamental functions and endpoint spaces.
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arxiv:2404.00707
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this paper reports the effort of deducing the initial strategy distributions of agents in mix - game model which is used to predict a real financial time series generated from a target financial market. using mix - game to predict shanghai index, we find the time series of prediction accurate rates is sensitive to the initial strategy distributions of agents in group 2 who play minority game, but less sensitive to the initial strategy distributions of agents in group 1 who play majority game. and agents in group 2 tend to cluster in full strategy space ( fss ) if the real financial time series has obvious tendency ( upward or downward ), otherwise they tend to scatter in fss. we also find that the initial strategy distributions and the number of agents in group 1 influence the level of prediction accurate rates. finally, this paper gives suggestion about further research.
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arxiv:physics/0603266
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surface waves on ferrofluids exposed to a dc - magnetic field exhibit a non - monotonic dispersion relation. the effect of a parametric driving on such waves is studied within suitable coupled ginzburg - landau equations. due to the non - monotonicity the neutral curve for the excitation of standing waves can have up to three minima. the stability of the waves with respect to long - wave perturbations is determined $ via $ a phase - diffusion equation. it shows that the band of stable wave numbers can split up into two or three sub - bands. the resulting competition between the wave numbers corresponding to the respective sub - bands leads quite naturally to patterns consisting of multiple domains of standing waves which differ in their wave number. the coarsening dynamics of such domain structures is addressed.
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arxiv:patt-sol/9601002
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extraction of the mass spectrum from twisted mass lattice qcd is facilitated by respecting the octahedral group of rotations and accommodating the broken parity and flavor symmetries of the theory. in this work, group theory meson operators adapted to these constraints are constructed for the special case of quark and antiquark fields at a common lattice site, connected by extended gauge field paths.
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arxiv:hep-lat/0609071
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a desperate search for a new campus and funding. eventually, the mit corporation approved a formal agreement to merge with harvard and move to allston, over the vehement objections of mit faculty, students, and alumni. the merger plan collapsed in 1905 when the massachusetts supreme judicial court ruled that mit could not sell its back bay land. in 1912, mit acquired its current campus by purchasing a one - mile ( 1. 6 km ) tract of filled lands along the cambridge side of the charles river. the neoclassical " new technology " campus was designed by william w. bosworth and had been funded largely by anonymous donations from a mysterious " mr. smith ", starting in 1912. in january 1920, the donor was revealed to be the industrialist george eastman, an inventor of film production methods and founder of eastman kodak. between 1912 and 1920, eastman donated $ 20 million ( $ 304. 2 million in 2024 dollars ) in cash and kodak stock to mit. in 1916, with the first academic buildings complete, the mit administration and the mit charter crossed the charles river on the ceremonial barge bucentaur built for the occasion. needing funds to match eastman ' s gift and cover retreating state support, president richard maclaurin launched an industry funding model known as the " technology plan " in 1920. as mit grew under the tech plan, it built new postgraduate programs that stressed laboratory work on industry problems, including a new program in electrical engineering. gerard swope, mit ' s chairman and head of general electric, believed talented engineers needed scientific research training. in 1930, he recruited karl taylor compton to helm mit ' s transformation as a " technological " research university and to build more autonomy from private industry. = = = curricular reforms = = =... a special type of educational institution which can be defined as a university polarized around science, engineering, and the arts. we might call it a university limited in its objectives but unlimited in the breadth and the thoroughness with which it pursues these objectives. in the 1930s, president karl taylor compton and vice - president ( effectively provost ) vannevar bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios. the compton reforms " renewed confidence in the ability of the institute to develop leadership in science as well as in engineering ". unlike ivy league schools, mit catered more to middle - class families, and depended more on tuition than on endowments or grants for its funding. still, as late as 1949, the lewis committee lame
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https://en.wikipedia.org/wiki/Massachusetts_Institute_of_Technology
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the kondo insulator smb6 is purported to develop into a robust topological insulator at low temperature. yet there are several puzzling and unexplained physical properties of the insulating bulk. it has been proposed that bulk spin excitons may be the source of these anomalies and may also adversely affect the topologically - protected metallic surface states. here, we report muon spin rotation measurements of smb6 that show thermally - activated behavior for the temperature dependences of the transverse - field ( tf ) relaxation rate below 20 k and muon knight shift below 5 - 6 k. our data are consistent with the freezing out of a bulk low - energy ( ~ 1 mev ) spin exciton concurrent with the appearance of metallic surface conductivity. furthermore, our results support the idea that spin excitons play some role in the anomalous low - temperature bulk properties of smb6.
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arxiv:1802.04295
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we study a model of random binary trees grown " by the leaves " in the style of luczak and winkler. if $ \ tau _ n $ is a uniform plane binary tree of size $ n $, luczak and winkler, and later explicitly caraceni and stauffer, constructed a measure $ \ nu _ { \ tau _ n } $ such that the tree obtained by adding a cherry on a leaf sampled according to $ \ nu _ { \ tau _ n } $ is still uniformly distributed on the set of all plane binary trees with size $ n + 1 $. it turns out that the measure $ \ nu _ { \ tau _ n } $, which we call the leaf - growth measure, is noticeably different from the uniform measure on the leaves of the tree $ \ tau _ n $. in fact, we prove that, as $ n \ to \ infty $, with high probability it is almost entirely supported by a subset of only $ n ^ { 3 ( 2 - \ sqrt { 3 } ) + o ( 1 ) } \ approx n ^ { 0. 8038... } $ leaves. in the continuous setting, we construct the scaling limit of this measure, which is a probability measure on the brownian continuum random tree supported by a fractal set of dimension $ 6 ( 2 - \ sqrt { 3 } ) $. we also compute the full ( discrete ) multifractal spectrum. this work is a first step towards understanding the diffusion limit of the discrete leaf - growth procedure.
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arxiv:2401.07891
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we implement an estimator for determining the separation between two incoherent point sources. this estimator relies on image inversion interferometry and when used with the appropriate data analytics, it yields an estimate of the separation with finite - error, even when the sources come arbitrarily close together. the experimental results show that the technique has a good tolerance to noise and misalignment, making it an interesting consideration for high resolution instruments.
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arxiv:1605.07297
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person re - identification is best known as the problem of associating a single person that is observed from one or more disjoint cameras. the existing literature has mainly addressed such an issue, neglecting the fact that people usually move in groups, like in crowded scenarios. we believe that the additional information carried by neighboring individuals provides a relevant visual context that can be exploited to obtain a more robust match of single persons within the group. despite this, re - identifying groups of people compound the common single person re - identification problems by introducing changes in the relative position of persons within the group and severe self - occlusions. in this paper, we propose a solution for group re - identification that grounds on transferring knowledge from single person re - identification to group re - identification by exploiting sparse dictionary learning. first, a dictionary of sparse atoms is learned using patches extracted from single person images. then, the learned dictionary is exploited to obtain a sparsity - driven residual group representation, which is finally matched to perform the re - identification. extensive experiments on the i - lids groups and two newly collected datasets show that the proposed solution outperforms state - of - the - art approaches.
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arxiv:1707.09173
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wesson obtained a limit on quantum and gravitational mass in the universe by combining the cosmological constant lambda, planck constant, the speed of light c, and also the gravitational constant g. the corresponding masses are 2. 0x10e - 62 kg and 2. 3e + 54 kg respectively, and in general can be obtained with the help of a generic dimensional analysis, or from an analysis where the cosmological constant appears in a four dimensional space - time and as a result of a higher dimensional reduction. in this paper our goal is to establish a relation for both quantum and gravitational mass as function of the information number bit n. for this reason, we first derive an expression for the cosmological constant as a function of information bit, since both masses depend on it, and then various resulting relations are explored, in relation to information number of bits n. fractional information bits imply no information extraction is possible. we see, that the order of magnitude of the various parameters as well as their ratios involve the large number 10e + 122, that is produced naturally from the fundamental parameters of modern cosmology. finally, we propose that in a complete quantum gravity theory the idea of information the might have to be included, with the quantum bits of information ( q - bits ) as one of its fundamental parameters, resulting thus to a more complete understanding of the universe, its laws, and its evolution.
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arxiv:1406.3041
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when a poincar \ ' e - invariant system spontaneously breaks continuous internal symmetries, goldstones ' s theorem demands the existence of massless, spin - zero excitations in a one - to - one correspondence with the broken symmetry generators. when a system spontaneously breaks poincar \ ' e symmetry, however, the kinds of excitations that satisfy goldstone ' s theorem can be quite unusual. in particular, they may have any spin and need not be particles or even quasiparticles. the standard coset construction used to formulate effective actions of goldstones, however, is rather restrictive and is incapable of generating the full spectrum of possibilities allowed by goldstone ' s theorem. we propose a ( partial ) remedy to this problem by postulating a novel coset construction for systems that spontaneously break poincar \ ' e symmetry. this new construction is capable of generating effective actions with a wide range of goldstone excitations - - - including fermionic degrees of freedom - - - even when all symmetries are bosonic. to demonstrate it ' s utility, we focus on constructing effective actions for point particles of various spins. we recover the known result that a particle of spin $ s $ requires an $ \ mathcal n = 2s $ supersymmetric worldline reparameterization gauge symmetry, which we implement at the level of the coset construction. in the process, we discover that massless particles require a novel kind of inverse higgs constraint that bears some resemblance to the dynamical inverse higgs constraints that appear in certain fermi liquid effective field theories. we then consider particles that, in addition to quantum spin, have finite spatial extent and are free to rotate. we derive a novel action for such particles and find a ` spin - orbital ' coupling between the intrinsic quantum spin and the physical - rotation degrees of freedom.
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arxiv:2010.11191
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we present statistical analysis of acoustic emission ( ae ) data from tensile experiments on paper sheets, loading mode i, with samples broken under strain control. the results are based on 100 experiments on unnotched samples and 70 samples with a long initial edge notch. first, ae energy release and ae event rates are considered for both cases, to test for the presence of " critical points " in fracture. for ae energy, no clear signatures are found, whereas the main finding is that the event rate diverges when a sample - dependent " critical time " of the maximum event rate is approached. this takes place after the maximum stress is reached. the results are compared with statistical fracture models of heterogenous materials. we also discuss the dependence of the ae energy and event interval distributions on average event rates.
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arxiv:1002.0821
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this paper presents a hierarchical, performance - based framework for the design optimization of multi - fingered soft grippers. to address the need for systematically defined performance indices, the framework structures the optimization process into three integrated layers : task space, motion space, and design space. in the task space, performance indices are defined as core objectives, while the motion space interprets these into specific movement primitives. finally, the design space applies parametric and topological optimization techniques to refine the geometry and material distribution of the system, achieving a balanced design across key performance metrics. the framework ' s layered structure enhances sg design, ensuring balanced performance and scalability for complex tasks and contributing to broader advancements in soft robotics.
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arxiv:2411.06294
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in the abelian case ( the subject of several beautiful books ) fixing some combinatorial structure ( so called theta structure of level k ) one obtains a special basis in the space of sections of canonical polarization powers over the jacobians. these sections can be presented as holomorphic functions on the " abelian schottky space ". this fact provides various applications of these concrete analytic formulas to the integrable systems, classical mechanics and pde ' s. our practical goal is to do the same in the non abelian case that is to give an answer to the beauville ' s question. in future we hope to extend this digest to a mathematical mohograph with title " vbac ".
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arxiv:math/0210466
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this discrepancy forced a change in some values in the standard model for particle physics. = = = neuroscience as a distinct discipline = = = the understanding of neurons and the nervous system became increasingly precise and molecular during the 20th century. for example, in 1952, alan lloyd hodgkin and andrew huxley presented a mathematical model for transmission of electrical signals in neurons of the giant axon of a squid, which they called " action potentials ", and how they are initiated and propagated, known as the hodgkin – huxley model. in 1961 – 1962, richard fitzhugh and j. nagumo simplified hodgkin – huxley, in what is called the fitzhugh – nagumo model. in 1962, bernard katz modeled neurotransmission across the space between neurons known as synapses. beginning in 1966, eric kandel and collaborators examined biochemical changes in neurons associated with learning and memory storage in aplysia. in 1981 catherine morris and harold lecar combined these models in the morris – lecar model. such increasingly quantitative work gave rise to numerous biological neuron models and models of neural computation. neuroscience began to be recognized as a distinct academic discipline in its own right. eric kandel and collaborators have cited david rioch, francis o. schmitt, and stephen kuffler as having played critical roles in establishing the field. = = = plate tectonics = = = geologists ' embrace of plate tectonics became part of a broadening of the field from a study of rocks into a study of the earth as a planet. other elements of this transformation include : geophysical studies of the interior of the earth, the grouping of geology with meteorology and oceanography as one of the " earth sciences ", and comparisons of earth and the solar system ' s other rocky planets. = = = applications = = = in terms of applications, a massive number of new technologies were developed in the 20th century. technologies such as electricity, the incandescent light bulb, the automobile and the phonograph, first developed at the end of the 19th century, were perfected and universally deployed. the first car was introduced by karl benz in 1885. the first airplane flight occurred in 1903, and by the end of the century airliners flew thousands of miles in a matter of hours. the development of the radio, television and computers caused massive changes in the dissemination of information. advances in biology also led to large increases in food production, as well as
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https://en.wikipedia.org/wiki/History_of_science
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the strong decays of $ d _ 1 ( 2420 ) ^ 0 $, $ d _ 2 ^ * ( 2460 ) ^ 0 $, $ d _ 2 ^ * ( 2460 ) ^ + $, $ d _ 2 ^ * ( 2460 ) ^ - $, $ d ( 2550 ) ^ 0 $, $ d _ j ^ * ( 2600 ) ^ 0 $, $ d ( 2740 ) ^ 0 $, $ d _ 3 ^ * ( 2750 ) ^ 0 $, $ d _ 3 ^ * ( 2750 ) ^ + $, $ d _ 3 ^ * ( 2750 ) ^ - $, $ d _ j ( 3000 ) ^ 0 $, $ d { _ { j } ^ * } ( 3000 ) ^ 0 $ and $ d _ 2 ^ * ( 3000 ) ^ 0 $ resonance states are analyzed in the heavy quark mass limit of heavy quark effective theory ( hqet ). the individual decay rates and the branching ratios among the strong decays determine their spin and parity. from such states the regge trajectories are constructed in $ ( j, m ^ 2 ) $ and $ ( n _ r, m ^ 2 ) $ planes and further predict the masses of higher excited states ( 1 $ ^ 1d _ 2 $, 1 $ ^ 3d _ 3 $, 3 $ ^ 1s _ 0 $, 3 $ ^ 3s _ 1 $, 1 $ ^ 1f _ 3 $, 1 $ ^ 3f _ 4 $, 2 $ ^ 3d _ 3 $, 3 $ ^ 3p _ 2 $ and 2 $ ^ 3f _ 4 $ ) lying on regge lines by fixing their slopes and intercepts. moreover, the strong decay rates and the branching ratios of these higher excited states are also examined, which can help the experimentalists to search these states into their respective decay modes.
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arxiv:1911.06063
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in this paper, the concept of musielak n - functions and musielak - orlicz spaces generated by them well be introduced. facts and results of the measure theory will be applied to consider properties, calculus and basic approximation of musielak n - functions and their musielak - orlicz spaces. finally, the relationship between musielak n - functions and musielak - orlicz functions and thier musielak - orlicz spaces will be considered using facts and results of the measure theory too
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arxiv:1806.07310
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using some basic notions from the theory of hopf algebras and quasi - shuffle algebras, we introduce rigorously a new family of rough paths : the quasi - geometric rough paths. we discuss their main properties. in particular, we will relate them with iterated brownian integrals and the concept of " simple bracket extension ", developed in the phd thesis of david kelly. as a consequence of these results, we have a sufficient criterion to show for any $ \ gamma \ in ( 0, 1 ) $ and any sufficiently smooth function $ \ varphi \ colon \ mathbb { r } ^ d \ to \ mathbb { r } $ a rough change of variable formula on any $ \ gamma $ - h \ " older continuous path $ x \ colon [ 0, t ] \ to \ mathbb { r } ^ d $, i. e. an explicit expression of $ \ varphi ( x _ t ) $ in terms of rough integrals.
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arxiv:2009.00903
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time evolution of entanglement of n quantum dots is analyzed within the spin - 1 / 2 van der waals ( or lipkin - meshkov - glick ) xy model. it is shown that, for a single dot initially excited and disentangled from the remaining unexcited dots, the maximum bipartite entanglement can be obtained in the systems of n = 2,..., 6 dots only.
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arxiv:quant-ph/0109144
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in su ( 3 ) lattice qcd formalism, we propose a method to extract gauge fields from link - variables analytically. with this method, we perform the first study on effective mass generation of off - diagonal gluons and infrared abelian dominance in the maximally abelian ( ma ) gauge in the su ( 3 ) case. using su ( 3 ) lattice qcd, we investigate the propagator and the effective mass of the gluon fields in the ma gauge with u ( 1 ) $ _ 3 \ timesu ( 1 ) _ 8 $ landau gauge fixing. the monte carlo simulation is performed on $ 16 ^ 4 $ at $ \ beta $ = 5. 7, 5. 8 and 6. 0 at the quenched level. the off - diagonal gluons behave as massive vector bosons with the approximate effective mass $ m _ { \ mathrm { off } } \ simeq 1. 1 - 1. 2 \ mathrm { gev } $ in the region of $ r = 0. 3 - 0. 8 $ fm, and the propagation is limited within a short range, while the propagation of diagonal gluons remains even in a large range. in this way, infrared abelian dominance is shown in terms of short - range propagation of off - diagonal gluons. furthermore, we investigate the functional form of the off - diagonal gluon propagator. the functional form is well described by the four - dimensional euclidean yukawa - type function $ e ^ { - m _ { \ rm off } r } / r $ with $ m _ { \ rm off } \ simeq 1. 3 - 1. 4 \ mathrm { gev } $ for $ r = 0. 1 - 0. 8 $ fm. this also indicates that the spectral function of off - diagonal gluons has the negative - value region.
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arxiv:1207.4377
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background : genome - scale metabolic network models and constraint - based modeling techniques have become important tools for analyzing cellular metabolism. thermodynamically infeasible cy - cles ( tics ) causing unbounded metabolic flux ranges are often encountered. tics satisfy the mass balance and directionality constraints but violate the second law of thermodynamics. current prac - tices involve implementing additional constraints to ensure not only optimal but also loopless flux distributions. however, the mixed integer linear programming problems required to solve become computationally intractable for genome - scale metabolic models. results : we aimed to identify the fewest needed constraints sufficient for optimality under the loop - less requirement. we found that loopless constraints are required only for the reactions that share elementary flux modes representing tics with reactions that are part of the objective function. we put forth the concept of localized loopless constraints ( llcs ) to enforce this minimal required set of loopless constraints. by combining with a novel procedure for minimal null - space calculation, the computational time for loopless flux variability analysis is reduced by a factor of 10 - 150 compared to the original loopless constraints and by 4 - 20 times compared to the currently fastest method fast - snp with the percent improvement increasing with model size. importantly, llcs offer a scalable strategy for loopless flux calculations for multi - compartment / multi - organism models of very large sizes ( e. g. > 104 reactions ) not feasible before. matlab functions are available at https : / / github. com / maranasgroup / lll - fva.
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arxiv:1711.04084
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we propose a novel iterative predictor - critic code decoding framework for real - world image dehazing, abbreviated as ipc - dehaze, which leverages the high - quality codebook prior encapsulated in a pre - trained vqgan. apart from previous codebook - based methods that rely on one - shot decoding, our method utilizes high - quality codes obtained in the previous iteration to guide the prediction of the code - predictor in the subsequent iteration, improving code prediction accuracy and ensuring stable dehazing performance. our idea stems from the observations that 1 ) the degradation of hazy images varies with haze density and scene depth, and 2 ) clear regions play crucial cues in restoring dense haze regions. however, it is non - trivial to progressively refine the obtained codes in subsequent iterations, owing to the difficulty in determining which codes should be retained or replaced at each iteration. another key insight of our study is to propose code - critic to capture interrelations among codes. the code - critic is used to evaluate code correlations and then resample a set of codes with the highest mask scores, i. e., a higher score indicates that the code is more likely to be rejected, which helps retain more accurate codes and predict difficult ones. extensive experiments demonstrate the superiority of our method over state - of - the - art methods in real - world dehazing.
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arxiv:2503.13147
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by means of neutron scattering we have determined new branches of magnetic excitations in orbitally active coo ( tn = 290 k ) up to 15 thz and for temperatures from 6 k to 450 k. data were taken in the ( 111 ) direction in six single - crystal zones. from the dependence on temperature and q we have identified several branches of magnetic excitation. we describe a model for the coupled orbital and spin states of co2 + subject to a crystal field and tetragonal distortion.
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arxiv:0706.3345
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we study long - term thermal evolution of neutron stars in soft x - ray transients ( sxts ), taking the deep crustal heating into account consistently with the changes of the composition of the crust. we collect observational estimates of average accretion rates and thermal luminosities of such neutron stars and compare the theory with observations. we perform simulations of thermal evolution of accreting neutron stars, considering the gradual replacement of the original nonaccreted crust by the reprocessed accreted matter, the neutrino and photon energy losses, and the deep crustal heating due to nuclear reactions in the accreted crust. we test and compare results for different modern theoretical models. we update a compilation of the observational estimates of the thermal luminosities in quiescence and average accretion rates in the sxts and compare the observational estimates with the theoretical results. long - term thermal evolution of transiently accreting neutron stars is nonmonotonic. the quasi - equilibrium temperature in quiescence reaches a minimum and then increases toward the final steady state. the quasi - equilibrium thermal luminosity of a neutron star in an sxt can be substantially lower at the minimum than in the final state. this enlarges the range of possibilities for theoretical interpretation of observations of such neutron stars. the updates of the theory and observations leave unchanged the previous conclusions that the direct urca process operates in relatively cold neutron stars and that an accreted heat - blanketing envelope is likely present in relatively hot neutron stars in the sxts in quiescence. the results of the comparison of theory with observations favor suppression of the triplet pairing type of nucleon superfluidity in the neutron - star matter.
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arxiv:1907.08299
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in this work we investigate the ability of a kinetic approach for traffic dynamics to predict speed distributions obtained through rough data. the present approach adopts the formalism of uncertainty quantification, since reaction strengths are uncertain and linked to different types of driver behaviour or different classes of vehicles present in the flow. therefore, the calibration of the expected speed distribution has to face the reconstruction of the distribution of the uncertainty. we adopt experimental microscopic measurements recorded on a german motorway, whose speed distribution shows a multimodal trend. the calibration is performed by extrapolating the uncertainty parameters of the kinetic distribution via a constrained optimisation approach. the results confirm the validity of the theoretical set - up.
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arxiv:1912.03706
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vision - and - language navigation ( vln ) agents are tasked with navigating an unseen environment using natural language instructions. in this work, we study if visual representations of sub - goals implied by the instructions can serve as navigational cues and lead to increased navigation performance. to synthesize these visual representations or imaginations, we leverage a text - to - image diffusion model on landmark references contained in segmented instructions. these imaginations are provided to vln agents as an added modality to act as landmark cues and an auxiliary loss is added to explicitly encourage relating these with their corresponding referring expressions. our findings reveal an increase in success rate ( sr ) of around 1 point and up to 0. 5 points in success scaled by inverse path length ( spl ) across agents. these results suggest that the proposed approach reinforces visual understanding compared to relying on language instructions alone. code and data for our work can be found at https : / / www. akhilperincherry. com / vln - imagine - website /.
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arxiv:2503.16394
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low - energy susy and several other theories that address the hierarchy problem predict pair - production at the lhc of particles with standard model quantum numbers that decay to jets, missing energy, and possibly leptons. if an excess of such events is seen in lhc data, a theoretical framework in which to describe it will be essential to constraining the structure of the new physics. we propose a basis of four deliberately simplified models, each specified by only 2 - 3 masses and 4 - 5 branching ratios, for use in a first characterization of data. fits of these simplified models to the data furnish a quantitative presentation of the jet structure, electroweak decays, and heavy - flavor content of the data, independent of detector effects. these fits, together with plots comparing their predictions to distributions in data, can be used as targets for describing the data within any full theoretical model.
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arxiv:0810.3921
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the microscopic quantum theory of nonlinear stimulated scattering of chiral particles in doped $ ab $ stacked bilayer graphene on coulomb field of charged impurities in the presence of strong coherent electromagnetic radiation is presented. the liouville - von neumann equation for the density matrix is solved analytically. here the interaction of electrons with the scattering potential is taken into account as a perturbation. the absorption rate of nonlinear inverse - bremsstrahlung for a grand canonical ensemble of fermionic chiral particles is calculated using the obtained solution. the analysis of the obtained rate shows that in the terahertz and near - infrared range of frequencies there is significant absorption of incident radiation via multiphoton stimulated bremsstrahlung mechanism.
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arxiv:1907.10673
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the expected low market penetration of connected vehicles ( cvs ) in the near future could be a constraint in estimating traffic flow parameters, such as average travel speed of a roadway segment and average space headway between vehicles from the cv broadcasted data. this estimated traffic flow parameters from low penetration of connected vehicles become noisy compared to 100 percent penetration of cvs, and such noise reduces the real time prediction accuracy of a machine learning model, such as the accuracy of long short term memory ( lstm ) model in terms of predicting traffic flow parameters. the accurate prediction of the parameters is important for future traffic condition assessment. to improve the prediction accuracy using noisy traffic flow parameters, which is constrained by limited cv market penetration and limited cv data, we developed a real time traffic data prediction model that combines lstm with kalman filter based rauch tung striebel ( rts ) noise reduction model. we conducted a case study using the enhanced next generation simulation ( ngsim ) dataset, which contains vehicle trajectory data for every one tenth of a second, to evaluate the performance of this prediction model. compared to a baseline lstm model performance, for only 5 percent penetration of cvs, the analyses revealed that combined lstm and rts model reduced the mean absolute percentage error ( mape ) from 19 percent to 5 percent for speed prediction and from 27 percent to 9 percent for space - headway prediction. the statistical significance test with a 95 percent confidence interval confirmed no significant difference in predicted average speed and average space headway using this lstm and rts combination with only 5 percent cv penetration rate.
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arxiv:1811.03562
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based on a system - reservoir model and an appropriate choice of nonlinear coupling, we have explored the microscopic quantum generalization of classical li \ ' { e } nard systems. making use of oscillator coherent states and canonical thermal distributions of the associated c - numbers, we have derived the quantum langevin equation of the reduced system which admits of single or multiple limit cycles. it has been shown that detailed balance in the form of fluctuation - dissipation relation preserves the dynamical stability of the attractors even in case of vacuum excitation. the quantum versions of rayleigh, van der pol and several other variants of li \ ' { e } nard oscillators are derived as special cases in our theoretical scheme within a mean - field description.
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arxiv:2009.07142
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time - dependent distribution of the global extinction of megafauna is compared with the growth of human population. there is no correlation between the two processes. furthermore, the size of human population and its growth rate were far too small to have any significant impact on the environment and on the life of megafauna.
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arxiv:1309.3002
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we study the distribution of lattice points with prime coordinates lying in the dilate of a convex planar domain having smooth boundary, with nowhere vanishing curvature. counting lattice points weighted by a von mangoldt function gives an asymptotic formula, with the main term being the area of the dilated domain, and our goal is to study the remainder term. assuming the riemann hypothesis, we give a sharp upper bound, and further assuming that the positive imaginary parts of the zeros of the riemann zeta functions are linearly independent over the rationals allows us to give a formula for the value distribution function of the properly normalized remainder term.
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arxiv:1803.03013
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in two previous papers the author presented a general construction of finite, fiber - and orientation - preserving group actions on orientable seifert manifolds. in this paper we restrict our attention to elliptic 3 - manifolds. a proof is given that orientation - reversing and fiber - preserving diffeomorphisms of seifert manifolds do not exist for nonzero euler class, in particular elliptic 3 - manifolds. each type of elliptic 3 - manifold is then considered and the possible group actions that fit the given construction. this is shown to be all but a few cases that have been considered elsewhere. finally, a presentation for the quotient space under such an action is constructed and a specific example is generated.
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arxiv:1911.03430
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the survival probability of large rapidity gaps in pp collisions is calculated for several different eikonal models of the gaussian form. results obtained for models based on partonic interactions are quite similar. the regge - pole model predicts a higher value of $ < \ vert s \ vert ^ { 2 } > $.
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arxiv:hep-ph/9302248
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we prove the existence of an affine paving for the three - step flag hilbert scheme $ $ \ text { hilb } ^ { n, n + 1, n + 2 } ( 0 ) : = \ left \ { \ mathbb { c } [ [ x, y ] ] \ supset i _ n \ supset i _ { n + 1 } \ supset i _ { n + 2 } : i _ i \, \, \ text { ideals with } \ text { dim } _ { \ mathbb { c } } { \ mathbb { c } [ x, y ] } / { i _ i } = i \ right \ } $ $ of 0 - dimensional subschemes that are supported at the origin of $ \ mathbb { c } ^ 2 $. this is done by showing that the space stratifies in smooth subvarieties, the hilbert - samuel ' s strata, each of which has an affine paving with cells of known dimension, indexed by marked young diagrams. the affine pavings of the hilbert - samuel ' s strata allow us to prove that the poincar \ ' { e } polynomials for $ \ text { hilb } ^ { n, n + 1, n + 2 } ( 0 ) $ satisfy : $ $ \ sum _ { n \ geq 0 } p _ q \ left ( \ text { hilb } ^ { n, n + 1, n + 2 } ( 0 ) \ right ) z ^ n = \ frac { q + 1 } { ( 1 - zq ) ( 1 - z ^ 2q ^ 2 ) } \, \, \ prod _ { k \ geq 1 } \ frac { 1 } { 1 - z ^ kq ^ { k - 1 } }. $ $ in the process of proving this formula we relate combinatorially the homology of our spaces with that of known subspaces of $ \ text { hilb } ^ { n + 1, n + 3 } ( 0 ) $. as a corollary we find an affine paving and a formula for the generating function of the poincar \ ' { e } polynomials of $ \ text { hilb } ^ { n, n + 2 } ( 0 ) $ for all $ n \ in \ mathbb { n } $.
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arxiv:1609.05005
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in a fundamental formulation of the quantum mechanics of a closed system such as the universe as a whole, three forms of information are needed to make predictions for the probabilities of alternative time histories of the closed system. these are the action functional of the elementary particles, the quantum istate of the universe, and the description of our specific history. we discuss the origin of the " quasiclassical realm " of familiar experience and hamiltonian quantum mechanics with its preferred time in such a formulation of quantum cosmology. it is argued that these features of the universe are not general properties of quantum theory, but rather approximate features that are emergent after the planck time as a consequence of theories of the closed system ' s quantum state and dynamics.
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arxiv:2103.08574
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adversarial imitation learning ( ail ) is a broad family of imitation learning methods designed to mimic expert behaviors from demonstrations. while ail has shown state - of - the - art performance on imitation learning with only small number of demonstrations, it faces several practical challenges such as potential training instability and implicit reward bias. to address the challenges, we propose support - weighted adversarial imitation learning ( sail ), a general framework that extends a given ail algorithm with information derived from support estimation of the expert policies. sail improves the quality of the reinforcement signals by weighing the adversarial reward with a confidence score from support estimation of the expert policy. we also show that sail is always at least as efficient as the underlying ail algorithm that sail uses for learning the adversarial reward. empirically, we show that the proposed method achieves better performance and training stability than baseline methods on a wide range of benchmark control tasks.
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arxiv:2002.08803
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thermally stimulated process such as evaporation, phase transition, or solid - liquid transition of a solid consumes each a certain portion of the solid cohesive energy that is the sum of bond energy over all the coordinates of all the involved atoms. generally, the critical temperatures for such processes drop with solid size, unless hetero capping or interfacial interaction becomes dominant, because of the increased portion of the lower - coordinated surface atoms [ sun et al., j. phys. chem. b108, 1080 ( 2004 ) ]. it is intriguing, however, that the melting point ( tm ) of a solid containing iii - a or iv - a atoms oscillates with size ( the tm drops first and then rises as the solid size is reduced ) and that the tm of chemically capped nanosolid often increases with the inverse size. here we show that bond nature evolution is essential for the selective nanosolids and at the junction interfaces, which is responsible for the superheating of the smallest nanosolids, chemically capped clusters, and junction interfaces that exhibit insulating nature with high mechanical strength.
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arxiv:cond-mat/0506105
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a - type stars have a complex internal structure with the possibility of multiple convection zones. if not sufficiently separated, such zones will interact through the convectively stable regions that lie between them. it is therefore of interest to ask whether the typical conditions that exist within such stars are such that these convections zones can ever be considered as disjoint. in this paper we present results from numerical simulations that help in understanding how increasing the distance between the convectively unstable regions are likely to interact through the stable region that separates them. this has profound implications for mixing and transport within these stars.
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arxiv:0706.2976
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we study both the local and global existence of a gradient flow of the sinai - ruelle - bowen entropy functional on a hilbert manifold of expanding maps of a circle equipped with a sobolev norm in the tangent space of the manifold. we show that, under a slightly modified metric, starting from any initial value, every trajectory of the gradient flow converges to the map with a constant expanding rate where the entropy attains the maximal value. in a simple case, we obtain an explicit formula for the flow ' s ordinary differential equation representation. this gradient flow has a close connection to a nonlinear partial differential equation : a gradient - dependent diffusion equation.
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arxiv:2306.12401
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fitts ' law is a linear equation relating movement time to an index of movement difficulty. the recent finding that fitts ' law applies to voluntary movement of the vocal tract raises the question of whether the theory of speech production implies fitts ' law. the present letter establishes a theoretical connection between fitts ' law and the task dynamics model of speech production. we derive a variant of fitts ' law where the intercept and slope are functions of the parameters of the task dynamics model and the index of difficulty is a product logarithm, or lambert w function, rather than a logarithm.
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arxiv:2001.05044
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existing interactive point cloud segmentation approaches primarily focus on the object segmentation, which aim to determine which points belong to the object of interest guided by user interactions. this paper concentrates on an unexplored yet meaningful task, i. e., interactive point cloud semantic segmentation, which assigns high - quality semantic labels to all points in a scene with user corrective clicks. concretely, we presents the first interactive framework for point cloud semantic segmentation, named interpcseg, which seamlessly integrates with off - the - shelf semantic segmentation networks without offline re - training, enabling it to run in an on - the - fly manner. to achieve online refinement, we treat user interactions as sparse training examples during the test - time. to address the instability caused by the sparse supervision, we design a stabilization energy to regulate the test - time training process. for objective and reproducible evaluation, we develop an interaction simulation scheme tailored for the interactive point cloud semantic segmentation task. we evaluate our framework on the s3dis and scannet datasets with off - the - shelf segmentation networks, incorporating interactions from both the proposed interaction simulator and real users. quantitative and qualitative experimental results demonstrate the efficacy of our framework in refining the semantic segmentation results with user interactions. the source code will be publicly available.
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arxiv:2403.06401
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in recent work arxiv : 2109. 07820 we have shown the equivalence of the widely used nonconvex ( generalized ) branched transport problem with a shape optimization problem of a street or railroad network, known as ( generalized ) urban planning problem. the argument was solely based on an explicit construction and characterization of competitors. in the current article we instead analyse the dual perspective associated with both problems. in more detail, the shape optimization problem involves the wasserstein distance between two measures with respect to a metric depending on the street network. we show a kantorovich $ \ unicode { x2013 } $ rubinstein formula for wasserstein distances on such street networks under mild assumptions. further, we provide a beckmann formulation for such wasserstein distances under assumptions which generalize our previous result in arxiv : 2109. 07820. as an application we then give an alternative, duality - based proof of the equivalence of both problems under a growth condition on the transportation cost, which reveals that urban planning and branched transport can both be viewed as two bilinearly coupled convex optimization problems.
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arxiv:2205.12049
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this paper proposes a generative moment matching network ( gmmn ) - based post - filter that provides inter - utterance pitch variation for deep neural network ( dnn ) - based singing voice synthesis. the natural pitch variation of a human singing voice leads to a richer musical experience and is used in double - tracking, a recording method in which two performances of the same phrase are recorded and mixed to create a richer, layered sound. however, singing voices synthesized using conventional dnn - based methods never vary because the synthesis process is deterministic and only one waveform is synthesized from one musical score. to address this problem, we use a gmmn to model the variation of the modulation spectrum of the pitch contour of natural singing voices and add a randomized inter - utterance variation to the pitch contour generated by conventional dnn - based singing voice synthesis. experimental evaluations suggest that 1 ) our approach can provide perceptible inter - utterance pitch variation while preserving speech quality. we extend our approach to double - tracking, and the evaluation demonstrates that 2 ) gmmn - based neural double - tracking is perceptually closer to natural double - tracking than conventional signal processing - based artificial double - tracking is.
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arxiv:1902.03389
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we consider the implications of low - energy precision tests of parity violation on t - channel mediator models explaining the top afb excess measured by cdf and d0. flavor - violating u - t or d - t couplings of new scalar or vector mediators generate at one - loop an anomalous contribution to the nuclear weak charge. as a result, atomic parity violation constraints disfavor at > 3 sigma t - channel models that give rise to a greater than 20 % afb at the parton level for m _ tt > 450 gev while not producing too large a top cross - section. even stronger constraints are expected through future measurements of the proton weak charge by the q - weak experiment.
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arxiv:1203.1320
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a new semi - supervised machine learning package is introduced which successfully solves the euclidean vacuum einstein equations with a cosmological constant, without any symmetry assumptions. the model architecture contains subnetworks for each patch in the manifold - defining atlas. each subnetwork predicts the components of a metric in that patch, with the associated einstein conditions, of the form $ r _ { \ mu \ nu } - \ lambda g _ { \ mu \ nu } = 0 $, being used as independent loss components ; in our conventions, $ \ mu, \ nu = 1, 2, \ cdots, n $, where $ n $ is the dimension of the riemannian manifold and $ \ lambda \ in \ { + 1, 0, - 1 \ } $. to ensure the consistency of the global structure of the manifold, another loss component is introduced across the patch subnetworks which enforces the coordinate transformation between the patches, $ g ' = j g j ^ t $, for an appropriate analytically known jacobian $ j $. we test our method for the case of spheres represented with 2 patches in dimensions $ 2, 3, 4, 5 $ ; in dimensions $ 2, 3 $ the geometries have been fully classified, however it is unknown whether a ricci - flat metric can be put on spheres in dimensions $ 4, 5 $, which we provide numerical evidence against.
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arxiv:2502.13043
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during his lifetime, ramanujan provided many formulae relating binomial sums to special values of the gamma function. based on numerical computations, van hamme recently conjectured $ p $ - adic analogues to such formulae. using a combination of ordinary and gaussian hypergeometric series, we prove one of these conjectures.
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arxiv:0708.3307
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