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applying a transformation to a non - gaussian field can enhance the information content of the resulting power spectrum, by reducing the correlations between fourier modes. in the context of weak gravitational lensing, it has been shown that this gain in information content is significantly compromised by the presence of shape noise. we apply clipping to mock convergence fields, a technique which is known to be robust in the presence of noise and has been successfully applied to galaxy number density fields. when analysed in isolation the resulting convergence power spectrum returns degraded constraints on cosmological parameters. however substantial gains can be achieved by performing a combined analysis of the power spectra derived from both the original and transformed fields. even in the presence of realistic levels of shape noise, we demonstrate that this approach is capable of reducing the area of likelihood contours within the $ \ omega _ m - \ sigma _ 8 $ plane by more than a factor of three.
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arxiv:1507.04862
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there has been an increased interest in the integration of pretrained speech recognition ( asr ) and language models ( lm ) into the slu framework. however, prior methods often struggle with a vocabulary mismatch between pretrained models, and lm cannot be directly utilized as they diverge from its nlu formulation. in this study, we propose a three - pass end - to - end ( e2e ) slu system that effectively integrates asr and lm subnetworks into the slu formulation for sequence generation tasks. in the first pass, our architecture predicts asr transcripts using the asr subnetwork. this is followed by the lm subnetwork, which makes an initial slu prediction. finally, in the third pass, the deliberation subnetwork conditions on representations from the asr and lm subnetworks to make the final prediction. our proposed three - pass slu system shows improved performance over cascaded and e2e slu models on two benchmark slu datasets, slurp and slue, especially on acoustically challenging utterances.
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arxiv:2307.11005
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subramanian defined the complexity class cc as the set of problems log - space reducible to the comparator circuit value problem. he proved that several other problems are complete for cc, including the stable marriage problem, and finding the lexicographical first maximal matching in a bipartite graph. we suggest alternative definitions of cc based on different reducibilities and introduce a two - sorted theory vcc * based on one of them. we sharpen and simplify subramanian ' s completeness proofs for the above two problems and formalize them in vcc *.
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arxiv:1106.4142
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the advent of noisy intermediate - scale quantum ( nisq ) computers raises a crucial challenge to design quantum neural networks for fully quantum learning tasks. to bridge the gap, this work proposes an end - to - end learning framework named qtn - vqc, by introducing a trainable quantum tensor network ( qtn ) for quantum embedding on a variational quantum circuit ( vqc ). the architecture of qtn is composed of a parametric tensor - train network for feature extraction and a tensor product encoding for quantum embedding. we highlight the qtn for quantum embedding in terms of two perspectives : ( 1 ) we theoretically characterize qtn by analyzing its representation power of input features ; ( 2 ) qtn enables an end - to - end parametric model pipeline, namely qtn - vqc, from the generation of quantum embedding to the output measurement. our experiments on the mnist dataset demonstrate the advantages of qtn for quantum embedding over other quantum embedding approaches.
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arxiv:2110.03861
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the magnetic reconnection process is studied in relativistic pair plasmas when the thermal and inertial properties of the magnetohydrodynamical fluid are included. we find that in both sweet - parker and petschek relativistic scenarios there is an increase of the reconnection rate owing to the thermal - inertial effects, both satisfying causality. to characterize the new effects we define a thermal - inertial number which is independent of the relativistic lundquist number, implying that reconnection can be achieved even for vanishing resistivity as a result of only thermal - inertial effects. the current model has fundamental importance for relativistic collisionless reconnection, as it constitutes the simplest way to get reconnection rates faster than those accessible with the sole resistivity.
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arxiv:1402.1115
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local energy extrema of the bands in momentum space, or valleys, can endow electrons in solids with pseudo - spin in addition to real spin. in transition metal dichalcogenides this valley pseudo - spin, like real spin, is associated with a magnetic moment which underlies the valley - dependent circular dichroism that allows optical generation of valley polarization, intervalley quantum coherence, and the valley hall effect. however, magnetic manipulation of valley pseudospin via this magnetic moment, analogous to what is possible with real spin, has not been shown before. here we report observation of the valley zeeman splitting and magnetic tuning of polarization and coherence of the excitonic valley pseudospin, by performing polarization - resolved magneto - photoluminescence on monolayer wse2. our measurements reveal both the atomic orbital and lattice contributions to the valley orbital magnetic moment ; demonstrate the deviation of the band edges in the valleys from an exact massive dirac fermion model ; and reveal a striking difference between the magnetic responses of neutral and charged valley excitons which is explained by renormalization of the excitonic spectrum due to strong exchange interactions.
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arxiv:1407.2645
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it is well known that for any irrational rotation number $ \ a $, the noncommutative torus $ \ ba _ \ a $ must have representations $ \ pi $ such that the generated von neumann algebra $ \ pi ( \ ba _ \ a ) " $ is of type $ \ ty { iii } $. therefore, it could be of interest to exhibit and investigate such kind of representations, together with the associated spectral triples whose twist of the dirac operator and the corresponding derivation arises from the tomita modular operator. in the present paper, we show that this program can be carried out, at least when $ \ a $ is a liouville number satisfying a faster approximation property by rationals. in this case, we exhibit several type $ \ ty { ii _ \ infty } $ and $ \ ty { iii _ \ l } $, $ \ l \ in [ 0, 1 ] $, factor representations and modular spectral triples. the method developed in the present paper can be generalised to ccr algebras based on a locally compact abelian group equipped with a symplectic form.
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arxiv:1806.08253
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in this paper we provide a principled approach to solve a transductive classification problem involving a similar graph ( edges tend to connect nodes with same labels ) and a dissimilar graph ( edges tend to connect nodes with opposing labels ). most of the existing methods, e. g., information regularization ( ir ), weighted vote relational neighbor classifier ( wvrn ) etc, assume that the given graph is only a similar graph. we extend the ir and wvrn methods to deal with mixed graphs. we evaluate the proposed extensions on several benchmark datasets as well as two real world datasets and demonstrate the usefulness of our ideas.
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arxiv:1206.6015
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in this paper, we study the exotic landau problem at the classical level where two conserved quantities are derived. at the quantum level, the corresponding quantum operators of the conserved quantities provide two oscillator representations from which we derive two boson fock spaces. using the normalized coherent states which are the minimum uncertainty states on non - commutative configuration space isomorphic to each of the boson fock space, we form entangled coherent states which are bell - like states labeled quasi - bell states. the effect of non - maximality of a quasi - bell state based quantum channel is investigated in the context of a teleportation of a qubit
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arxiv:2404.02941
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m. daher gave conditions so that the spheres of the spaces in the interior of a complex interpolation scale are uniformly homeomorphic. we look for sufficient conditions for the validity of this result and related ones on the extremes of the scale, with applications to uniform homeomorphism between spheres of banach spaces and the sphere of $ \ ell _ 2 $.
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arxiv:2405.03867
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in this article, we give examples of smooth varieties of positive characteristic whose first integral overconvergent de rham - witt cohomology modulo torsion is not finitely generated over the witt ring of the base field.
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arxiv:1812.03720
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given reduced amalgamated free products of c $ ^ * $ - algebras, $ ( a, phi ) = * _ i ( a _ i, phi _ i ) $ and $ ( d, psi ) = * _ i ( d _ i, psi _ i ) $, an embedding $ a \ to d $ is shown to exist assuming there are conditional expectation preserving embeddings $ a _ i \ to d _ i $. this result is extended to show the existance of the reduced amalgamated free product of certain classes of unital completely positive maps. analogues of the above mentioned results are proved for von neumann algebras.
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arxiv:math/9911012
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in distributed manipulator systems ( dms ), decentralization is a highly desirable property as it promotes robustness and facilitates scalability by distributing computational burden and eliminating singular points of failure. however, current dms typically utilize a centralized approach to sensing, such as single - camera computer vision systems. this centralization poses a risk to system reliability and offers a significant limiting factor to system size. in this work, we introduce a decentralized approach for sensing and in a distributed manipulator systems using neural cellular automata ( nca ). demonstrating a decentralized sensing in a hardware implementation, we present a novel inductive sensor board designed for distributed sensing and evaluate its ability to estimate global object properties, such as the geometric center, through local interactions and computations. experiments demonstrate that nca - based sensing networks accurately estimate object position at 0. 24 times the inter sensor distance. they maintain resilience under sensor faults and noise, and scale seamlessly across varying network sizes. these findings underscore the potential of local, decentralized computations to enable scalable, fault - tolerant, and noise - resilient object property estimation in dms
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arxiv:2502.01242
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applying logic in the area of conceptual modeling has been investigated widely, yet there has been limited uptake of logic - based conceptual modeling in industry. according to some researchers, another formalization of such tools as eer or uml class diagrams in logic may only marginally contribute to the body of knowledge. this paper reflects on applying propositional logic language to a high - level diagrammatic representation called the thinging machines ( tm ) model. we explore the relationship between conceptual modeling and logic, including such issues as : what logical constructs model? how does truth fit into the picture produced in conceptual modeling as a representation of some piece of the world it is about? the ultimate research objective is a quest for a thorough semantic alignment of tm modeling and propositional logic into a single structure. examples that involve the application of propositional logic in certain areas of reality are tm remodeled, where propositions are viewed as tm regions or events. as it turned out, tm seems to shed light on the semantics of propositions. in such a conceptual framework, logical truth is a matter of how things are in actuality and how falsehood is in subsistence. the results show that propositional logic enriches the rigorousness of conceptual descriptions and that the tm semantic apparatus complements propositional logic by providing a background to the given set of propositions. semantics matters are applied to propositional constructs such as negative propositions, disjunctions, and conjunctions with negative terms.
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arxiv:2409.15705
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commercial quartz oscillators of the tuning - fork type with a resonant frequency of ~ 32 khz have been investigated in helium liquids. the oscillators are found to have at best q values in the range 10 ^ 5 - 10 ^ 6, when measured in vacuum below 1. 5 k. however, the variability is large and for very low temperature operation the sensor has to be preselected. we explore their properties in the regime of linear viscous hydrodynamic response in normal and superfluid 3he and 4he, by comparing measurements to the hydrodynamic model of the sensor.
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arxiv:cond-mat/0608385
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we study proper, isometric actions of nonsolvable discrete groups gamma on the 3 - dimensional minkowski space r ^ { 2, 1 } as limits of actions on the 3 - dimensional anti - de sitter space ads ^ 3. to each such action is associated a deformation of a hyperbolic surface group gamma _ 0 inside o ( 2, 1 ). when gamma _ 0 is convex cocompact, we prove that gamma acts properly on r ^ { 2, 1 } if and only if this group - level deformation is realized by a deformation of the quotient surface that everywhere contracts distances at a uniform rate. we give two applications in this case. ( 1 ) tameness : a complete flat spacetime is homeomorphic to the interior of a compact manifold. ( 2 ) geometric degeneration : a complete flat spacetime is the rescaled limit of collapsing ads spacetimes.
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arxiv:1306.2240
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scalable coding, which can adapt to channel bandwidth variation, performs well in today ' s complex network environment. however, most existing scalable compression methods face two challenges : reduced compression performance and insufficient scalability. to overcome the above problems, this paper proposes a learned fine - grained scalable image compression framework, namely deepfgs. specifically, we introduce a feature separation backbone to divide the image information into basic and scalable features, then redistribute the features channel by channel through an information rearrangement strategy. in this way, we can generate a continuously scalable bitstream via one - pass encoding. for entropy coding, we design a mutual entropy model to fully explore the correlation between the basic and scalable features. in addition, we reuse the decoder to reduce the parameters and computational complexity. experiments demonstrate that our proposed deepfgs outperforms previous learning - based scalable image compression models and traditional scalable image codecs in both psnr and ms - ssim metrics.
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arxiv:2412.00437
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the main contribution to hard elastic scattering comes from components of wave functions of colliding hadrons that contain minimum number of partons. we discuss this mechanism in regge and parton approaches and estimate the probabilities that colliding hadrons are in such bare states. the behavior of cross - sections in this regime at various energies can give nontrivial information on high energy dynamics.
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arxiv:1012.5385
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in contrast to ensembles of singular gauge instantons, which are well known to fail to produce confinement, it is shown that effective theories based on ensembles of merons or regular gauge instantons do produce confinement. furthermore, when the scale is set by the string tension, the action density, topological susceptibility, and glueball masses are similar to those arising in lattice qcd.
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arxiv:hep-lat/0409083
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using the idea of itzykson - zuber integral, unitary - matrix integration of 2d yang - mills action is presented. the uniqueness of the solution of heat equation enables us to integrate out the unitary - matrix parts of hermite matrices and to obtain the expression of integration over vectors, also in this case.
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arxiv:hep-th/0303240
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we developed a jitted compiler for training artificial neural networks using c + +, llvm and cuda. it features object - oriented characteristics, strong typing, parallel workers for data pre - processing, pythonic syntax for expressions, pytorch like model declaration and automatic differentiation. we implement the mechanisms of cache and pooling in order to manage vram, cublas for high performance matrix multiplication and cudnn for convolutional layers. our experiments with residual convolutional neural networks on imagenet, we reach similar speed but degraded performance. also, the gru network experiments show similar accuracy, but our compiler have degraded speed in that task. however, our compiler demonstrates promising results at the cifar - 10 benchmark, in which we reach the same performance and about the same speed as pytorch. we make the code publicly available at : https : / / github. com / nosaveddata / nosavedkaleidoscope
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arxiv:2409.11600
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large - scale vision - language models ( vlms ), trained on extensive datasets of image - text pairs, exhibit strong multimodal understanding capabilities by implicitly learning associations between textual descriptions and image regions. this emergent ability enables zero - shot object detection and segmentation, using techniques that rely on text - image attention maps, without necessarily training on abundant labeled segmentation datasets. however, performance of such methods depends heavily on prompt engineering and manually selected layers or head choices for the attention layers. in this work, we demonstrate that, rather than relying solely on textual prompts, providing a single visual example for each category and fine - tuning the text - to - image attention layers and embeddings significantly improves the performance. additionally, we propose learning an ensemble through few - shot fine - tuning across multiple layers and / or prompts. an entropy - based ranking and selection mechanism for text - to - image attention layers is proposed to identify the top - performing layers without the need for segmentation labels. this eliminates the need for hyper - parameter selection of text - to - image attention layers, providing a more flexible and scalable solution for open - vocabulary segmentation. we show that this approach yields strong zero - shot performance, further enhanced through fine - tuning with a single visual example. moreover, we demonstrate that our method and findings are general and can be applied across various vision - language models ( vlms ).
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arxiv:2503.10779
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given a good $ n $ - tilting module $ t $ over a ring $ a $, let $ b $ be the endomorphism ring of $ t $, it is an open question whether the kernel of the left - derived functor $ t \ otimes ^ l _ b - $ between the derived module categories of $ b $ and $ a $ could be realized as the derived module category of a ring $ c $ via a ring epimorphism $ b \ rightarrow c $ for $ n \ ge 2 $. in this paper, we first provide a uniform way to deal with the above question both for tilting and cotilting modules by considering a new class of modules called ringel modules, and then give criterions for the kernel of $ t \ otimes ^ l _ b - $ to be equivalent to the derived module category of a ring $ c $ with a ring epimorphism $ b \ rightarrow c $. using these characterizations, we display both a positive example of $ n $ - tilting modules from noncommutative algebra, and a counterexample of $ n $ - tilting modules from commutative algebra to show that, in general, the open question may have a negative answer. as another application of our methods, we consider the dual question for cotilting modules, and get corresponding criterions and counterexamples. the case of cotilting modules, however, is much more complicated than the case of tilting modules.
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arxiv:1206.0522
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7. 5 million. peer 1 hosting entered the uk managed hosting market in january 2009 and the serverbeach brand now competes directly with the uk arm of rackspace, run by dominic monkhouse, former managing director of rackspace limited. in october 2006, mosso inc. was launched, which experimented with white - labeling hosting services. eventually, the division became the foundation for the rackspace cloud computing offering. on october 1, 2007, rackspace acquired webmail. us, a private e - mail hosting firm located in blacksburg, va. originally branded as mailtrust on may 20, 2009, it became part of the newly formed cloud office division of rackspace. on october 22, 2008, rackspace acquired slicehost, a provider of virtual servers and jungle disk, a provider of online backup software and services. rackspace announced on march 8, 2017, plans for an expansion to its portfolio to include managed service for the google cloud platform. the program began beta testing on july 18, 2017, with a planned full offering in late 2017. rackspace partnered with google in customer reliability engineering, a group of google site reliability engineers, to ensure cloud applications " run with the same speed and reliability as some of google ' s most widely - used products ". = = openstack = = in 2010, rackspace contributed the source code of its cloud files product to the openstack project under the apache license to become the openstack object storage component. in april 2012, rackspace announced it would implement openstack compute as the underlying technology for their cloud servers product. this change introduced a new control panel as well as add - on cloud services offering databases, server monitoring, block storage, and virtual networking. in 2015, two rackspace executives were elected to the board of the openstack foundation. in a february 2016 interview, cto john engates stated that rackspace uses openstack to power their public and private cloud. = = recognition = = fortune ' s " top 100 best companies to work for 2008 " placed rackspace as no. 32. in 2011 and 2013, the company was named as one of the top 100 places to work by fortune. = = references = =
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https://en.wikipedia.org/wiki/Rackspace_Technology
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agent - based modelling ( abm ) is a facet of wider multi - agent systems ( mas ) research that explores the collective behaviour of individual ` agents ', and the implications that their behaviour and interactions have for wider systemic behaviour. the method has been shown to hold considerable value in exploring and understanding human societies, but is still largely confined to use in academia. this is particularly evident in the field of urban analytics ; one that is characterised by the use of new forms of data in combination with computational approaches to gain insight into urban processes. in urban analytics, abm is gaining popularity as a valuable method for understanding the low - level interactions that ultimately drive cities, but as yet is rarely used by stakeholders ( planners, governments, etc. ) to address real policy problems. this paper presents the state - of - the - art in the application of abm at the interface of mas and urban analytics by a group of abm researchers who are affiliated with the urban analytics programme of the alan turing institute in london ( uk ). it addresses issues around modelling behaviour, the use of new forms of data, the calibration of models under high uncertainty, real - time modelling, the use of ai techniques, large - scale models, and the implications for modelling policy. the discussion also contextualises current research in wider debates around data science, artificial intelligence, and mas more broadly.
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arxiv:2210.06955
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in this paper, we get several new results on permutation polynomials over finite fields. first, by using the linear translator, we construct permutation polynomials of the forms $ l ( x ) + \ sum _ { j = 1 } ^ k \ gamma _ jh _ j ( f _ j ( x ) ) $ and $ x + \ sum _ { j = 1 } ^ k \ gamma _ jf _ j ( x ) $. these generalize the results obtained by kyureghyan in 2011. consequently, we characterize permutation polynomials of the form $ l ( x ) + \ sum _ { i = 1 } ^ l \ gamma _ i { \ rm tr } _ { { \ bf f } _ { q ^ m } / { \ bf f } _ { q } } ( h _ i ( x ) ) $, which extends a theorem of charpin and kyureghyan obtained in 2009.
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arxiv:1403.6012
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traffic congestion research is on the rise, thanks to urbanization, economic growth, and industrialization. developed countries invest a lot of research money in collecting traffic data using radio frequency identification ( rfid ), loop detectors, speed sensors, high - end traffic light, and gps. however, these processes are expensive, infeasible, and non - scalable for developing countries with numerous non - motorized vehicles, proliferated ride - sharing services, and frequent pedestrians. this paper proposes a novel approach to collect traffic data from google map ' s traffic layer with minimal cost. we have implemented widely used models such as historical averages ( ha ), support vector regression ( svr ), support vector regression with graph ( svr - graph ), auto - regressive integrated moving average ( arima ) to show the efficacy of the collected traffic data in forecasting future congestion. we show that even with these simple models, we could predict the traffic congestion ahead of time. we also demonstrate that the traffic patterns are significantly different between weekdays and weekends.
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arxiv:2011.02359
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isizulu is one of the eleven official languages of south africa and roughly half the population can speak it. it is the first ( home ) language for over 10 million people in south africa. only a few computational resources exist for isizulu and its related nguni languages, yet the imperative for tool development exists. we focus on natural language generation, and the grammar options and preferences in particular, which will inform verbalization of knowledge representation languages and could contribute to machine translation. the verbalization pattern specification shows that the grammar rules are elaborate and there are several options of which one may have preference. we devised verbalization patterns for subsumption, basic disjointness, existential and universal quantification, and conjunction. this was evaluated in a survey among linguists and non - linguists. some differences between linguists and non - linguists can be observed, with the former much more in agreement, and preferences depend on the overall structure of the sentence, such as singular for subsumption and plural in other cases.
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arxiv:1406.1870
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in this paper, we investigate the asymptotic symmetry and monotonicity of positive solutions to a reaction - diffusion equation in the unit ball, utilizing techniques from elliptic geometry. firstly, we discuss the properties of solutions in the elliptic space. then, we establish crucial principles, including the asymptotic narrow region principle. finally, we employ the method of moving planes to demonstrate the asymptotic symmetry of the solutions.
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arxiv:2409.05366
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we report new zero - field muon spin relaxation and neutron spin echo measurements in ferromagnetic ( fm ) ( la, ca ) mno3 which taken together suggest two spatially separated regions in close proximity possessing very different mn - ion spin dynamics. one region corresponds to an extended cluster which displays ' critical slowing down ' near tc and an increasing volume fraction below tc. the second region possesses more slowly fluctuating spins and a decreasing volume fraction below tc. these data are discussed in terms of the growth of small polarons into overlapping regions of correlated spins below tc, resulting in a microscopically inhomogeneous fm transition.
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arxiv:cond-mat/9910064
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this paper presents a groundbreaking self - improving interference management framework tailored for wireless communications, integrating deep learning with uncertainty quantification to enhance overall system performance. our approach addresses the computational challenges inherent in traditional optimization - based algorithms by harnessing deep learning models to predict optimal interference management solutions. a significant breakthrough of our framework is its acknowledgment of the limitations inherent in data - driven models, particularly in scenarios not adequately represented by the training dataset. to overcome these challenges, we propose a method for uncertainty quantification, accompanied by a qualifying criterion, to assess the trustworthiness of model predictions. this framework strategically alternates between model - generated solutions and traditional algorithms, guided by a criterion that assesses the prediction credibility based on quantified uncertainties. experimental results validate the framework ' s efficacy, demonstrating its superiority over traditional deep learning models, notably in scenarios underrepresented in the training dataset. this work marks a pioneering endeavor in harnessing self - improving deep learning for interference management, through the lens of uncertainty quantification.
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arxiv:2401.13206
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with a view towards providing tools for analyzing and understanding digitized images, various notions from algebraic topology have been introduced into the setting of digital topology. in the ordinary topological setting, invariants such as the fundamental group are invariants of homotopy type. in the digital setting, however, the usual notion of homotopy leads to a very rigid invariance that does not correspond well with the topological notion of homotopy invariance. in this paper, we establish fundamental results about subdivision of maps of digital images with $ 1 $ - or $ 2 $ - dimensional domains. our results lay the groundwork for showing that the digital fundamental group is an invariant of a much less rigid equivalence relation on digital images, that is more akin to the topological notion of homotopy invariance. our results also lay the groundwork for defining other invariants of digital images in a way that makes them invariants of this less rigid equivalence.
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arxiv:1906.03170
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using the decoherence formalism of gell - mann and hartle, a quantum system is found which is the equivalent of the classical chaotic duffing oscillator. the similarities and the differences from the classical oscillator are examined ; in particular, a new concept of quantum maps is introduced, and alterations in the classical strange attractor due to the presence of scale - dependent quantum effects are studied. classical quantities such as the lyapunov exponents and fractal dimension are examined, and quantum analogs are suggested. these results are generalized into a framework for quantum dissipative chaos, and there is a brief discussion of other work in this area.
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arxiv:chao-dyn/9307018
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we construct vertex operators for massless higher spin fields in rns superstring theory and compute some of their three - point correlators, describing gauge - invariant cubic interactions of the massless higher spins. the fierz - pauli on - shell conditions for the higher spins ( including tracelessness and vanishing divergence ) follow from the brst - invariance conditions for the vertex operators constructed in this paper. the gauge symmetries of the massless higher spins emerge as a result of the brst nontriviality conditions for these operators, being equivalent to transformations with the traceless gauge parameter in the fronsdal ' s approach. the gauge invariance of the interaction terms of the higher spins is therefore ensured automatically by that of the vertex operators in string theory. we develop general algorithm to compute the cubic interactions of the massless higher spins and use it to explicitly describe the gauge - invariant interaction of two $ s = 3 $ and one $ s = 4 $ massless particles.
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arxiv:0910.5338
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a } ^ { 1 } \ times \ mathbb { a } ^ { 2 } : y ^ { 2 } = x ( x - 1 ) ( x - t ) \ right \ } } where a 1 { \ displaystyle \ mathbb { a } ^ { 1 } } is the affine line and a 2 { \ displaystyle \ mathbb { a } ^ { 2 } } is the affine plane. since we are considering complex varieties, these are equivalently the spaces c, c 2 { \ displaystyle \ mathbb { c }, \ mathbb { c } ^ { 2 } } of the complex line and the complex plane. note that we should actually remove the points t = 0, 1 { \ displaystyle t = 0, 1 } because there are singularities ( since there is a double root ). = = local normal form = = if f : m β n is a submersion at p and f ( p ) = q β n, then there exists an open neighborhood u of p in m, an open neighborhood v of q in n, and local coordinates ( x1, β¦, xm ) at p and ( x1, β¦, xn ) at q such that f ( u ) = v, and the map f in these local coordinates is the standard projection f ( x 1, β¦, x n, x n + 1, β¦, x m ) = ( x 1, β¦, x n ). { \ displaystyle f ( x _ { 1 }, \ ldots, x _ { n }, x _ { n + 1 }, \ ldots, x _ { m } ) = ( x _ { 1 }, \ ldots, x _ { n } ). } it follows that the full preimage fβ1 ( q ) in m of a regular value q in n under a differentiable map f : m β n is either empty or a differentiable manifold of dimension dim m β dim n, possibly disconnected. this is the content of the regular value theorem ( also known as the submersion theorem ). in particular, the conclusion holds for all q in n if the map f is a submersion. = = topological manifold submersions = = submersions are also well - defined for general topological manifolds. a topological manifold submersion is a continuous surjection f : m β n such that for all p in m, for some continuous charts Ο at p and Ο at
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https://en.wikipedia.org/wiki/Submersion_(mathematics)
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we propose an information - theoretic model for the transport of waves through a chaotic cavity in the presence of absorption. the entropy of the s - matrix statistical distribution is maximized, with the constraint $ < tr ss ^ { \ dagger } > = \ alpha n $ : n is the dimensionality of s, and $ 0 \ leq \ alpha \ leq 1, \ alpha = 0 ( 1 ) $ meaning complete ( no ) absorption. for strong absorption our result agrees with a number of analytical calculations already given in the literature. in that limit, the distribution of the individual ( angular ) transmission and reflection coefficients becomes exponential - rayleigh statistics - even for n = 1. for $ n \ gg 1 $ rayleigh statistics is attained even with no absorption ; here we extend the study to $ \ alpha < 1 $. the model is compared with random - matrix - theory numerical simulations : it describes the problem very well for strong absorption, but fails for moderate and weak absorptions. thus, in the latter regime, some important physical constraint is missing in the construction of the model.
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arxiv:cond-mat/9905177
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we prove a general form of green formula and cauchy integral theorem for arbitrary closed rectifiable curves in the plane.
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arxiv:1306.6832
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the theoretical status of perturbative qed and qcd corrections to deep inelastic scattering is reviewed.
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arxiv:hep-ph/9512272
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recently, there has been tremendous interest in industry 4. 0 infrastructure to address labor shortages in global supply chains. deploying artificial intelligence - enabled robotic bin picking systems in real world has become particularly important for reducing stress and physical demands of workers while increasing speed and efficiency of warehouses. to this end, artificial intelligence - enabled robotic bin picking systems may be used to automate order picking, but with the risk of causing expensive damage during an abnormal event such as sensor failure. as such, reliability becomes a critical factor for translating artificial intelligence research to real world applications and products. in this paper, we propose a reliable object detection and segmentation system with multimodal redundancy ( mmrnet ) for tackling object detection and segmentation for robotic bin picking using data from different modalities. this is the first system that introduces the concept of multimodal redundancy to address sensor failure issues during deployment. in particular, we realize the multimodal redundancy framework with a gate fusion module and dynamic ensemble learning. finally, we present a new label - free multi - modal consistency ( mc ) score that utilizes the output from all modalities to measure the overall system output reliability and uncertainty. through experiments, we demonstrate that in an event of missing modality, our system provides a much more reliable performance compared to baseline models. we also demonstrate that our mc score is a more reliability indicator for outputs during inference time compared to the model generated confidence scores that are often over - confident.
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arxiv:2210.10842
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for irrotational dust the shear tensor is consistently diagonalizable with its covariant time derivative : $ \ sigma _ { ab } = 0 = \ dot { \ sigma } _ { ab }, \ ; a \ neq b $, if and only if the divergence of the magnetic part of the weyl tensor vanishes : $ div ~ h = 0 $. we show here that in that case, the consistency of the ricci constraints requires that the magnetic part of the weyl tensor itself vanishes : $ h _ { ab } = 0 $.
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arxiv:gr-qc/9508049
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for a matching $ m $ in a graph $ g $, let $ g ( m ) $ be the subgraph of $ g $ induced by the vertices of $ g $ that are incident with an edge in $ m $. the matching $ m $ is induced, if $ g ( m ) $ is $ 1 $ - regular, and $ m $ is uniquely restricted, if $ m $ is the unique perfect matching of $ g ( m ) $. the induced matching number $ \ nu _ s ( g ) $ of $ g $ is the largest size of an induced matching in $ g $, and the uniquely restricted matching number $ \ nu _ { ur } ( g ) $ of $ g $ is the largest size of a uniquely restricted matching in $ g $. golumbic, hirst, and lewenstein ( uniquely restricted matchings, algorithmica 31 ( 2001 ) 139 - 154 ) posed the problem to characterize the graphs $ g $ with $ \ nu _ s ( g ) = \ nu _ { ur } ( g ) $. we give a complete characterization of the $ 2 $ - connected subcubic graphs $ g $ of sufficiently large order with $ \ nu _ s ( g ) = \ nu _ { ur } ( g ) $. as a consequence, we are able to show that the subcubic graphs $ g $ with $ \ nu _ s ( g ) = \ nu _ { ur } ( g ) $ can be recognized in polynomial time.
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arxiv:1807.08981
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the malliavin differentiability of a sde plays a crucial role in the study of density smoothness and ergodicity among others. for gaussian driven sdes the differentiability property is now well established. in this paper, we consider the malliavin differentiability for the euler scheme of such sdes. we will focus on sdes driven by fractional brownian motions ( fbm ), which is a very natural class of gaussian processes. we derive a uniform ( in the step size $ n $ ) path - wise upper - bound estimate for the euler scheme for stochastic differential equations driven by fbm with hurst parameter $ h > 1 / 3 $ and its malliavin derivatives.
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arxiv:2305.10365
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spatio - temporal forecasting is a critical component of various smart city applications, such as transportation optimization, energy management, and socio - economic analysis. recently, several automated spatio - temporal forecasting methods have been proposed to automatically search the optimal neural network architecture for capturing complex spatio - temporal dependencies. however, the existing automated approaches suffer from expensive neural architecture search overhead, which hinders their practical use and the further exploration of diverse spatio - temporal operators in a finer granularity. in this paper, we propose autostf, a decoupled automatic neural architecture search framework for cost - effective automated spatio - temporal forecasting. from the efficiency perspective, we first decouple the mixed search space into temporal space and spatial space and respectively devise representation compression and parameter - sharing schemes to mitigate the parameter explosion. the decoupled spatio - temporal search not only expedites the model optimization process but also leaves new room for more effective spatio - temporal dependency modeling. from the effectiveness perspective, we propose a multi - patch transfer module to jointly capture multi - granularity temporal dependencies and extend the spatial search space to enable finer - grained layer - wise spatial dependency search. extensive experiments on eight datasets demonstrate the superiority of autostf in terms of both accuracy and efficiency. specifically, our proposed method achieves up to 13. 48x speed - up compared to state - of - the - art automatic spatio - temporal forecasting methods while maintaining the best forecasting accuracy.
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arxiv:2409.16586
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##logical algebra, fibrations and cofibrations in topology and more generally model categories. two functors f : c β d and g : d β c are adjoint if for all objects c in c and d in d in a natural way. actually, the correspondence of limits and colimits is an example of adjoints, since there is an adjunction between the colimit functor that assigns to any diagram in c indexed by some category i its colimit and the diagonal functor that maps any object c of c to the constant diagram which has c at all places. dually, = = = spaces and functions = = = gelfand duality is a duality between commutative c * - algebras a and compact hausdorff spaces x is the same : it assigns to x the space of continuous functions ( which vanish at infinity ) from x to c, the complex numbers. conversely, the space x can be reconstructed from a as the spectrum of a. both gelfand and pontryagin duality can be deduced in a largely formal, category - theoretic way. in a similar vein there is a duality in algebraic geometry between commutative rings and affine schemes : to every commutative ring a there is an affine spectrum, spec a. conversely, given an affine scheme s, one gets back a ring by taking global sections of the structure sheaf os. in addition, ring homomorphisms are in one - to - one correspondence with morphisms of affine schemes, thereby there is an equivalence ( commutative rings ) op ( affine schemes ) affine schemes are the local building blocks of schemes. the previous result therefore tells that the local theory of schemes is the same as commutative algebra, the study of commutative rings. noncommutative geometry draws inspiration from gelfand duality and studies noncommutative c * - algebras as if they were functions on some imagined space. tannaka β krein duality is a non - commutative analogue of pontryagin duality. = = = galois connections = = = in a number of situations, the two categories which are dual to each other are actually arising from partially ordered sets, i. e., there is some notion of an object " being smaller " than another one. a duality that respects the orderings in question is known as a galois connection. an example is the standard duality in gal
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https://en.wikipedia.org/wiki/Duality_(mathematics)
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we will explain how to compute the exact $ l ^ p $ operator norm of a " quadratic perturbation " of the real part of the ahlfors - - beurling operator. for the lower bound estimate we use a new approach of constructing a sequence of laminates ( probability measures for which jensen ' s inequality holds, but for rank one concave functions ) to give an almost extremal sequence to approximate the operator. the upper bound estimate is given by extending the estimates of the quadratic perturbation of the martingale transform to continuous martingales. the use of " heat martingales " then allow us to connect the riesz transforms to the continuous martingale estimate.
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arxiv:1109.4865
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we study the role of light neutron - rich nuclei during r - process nucleosynthesis in supernovae. most previous studies of the r - process have concentrated on the reaction flow of heavy unstable nuclei. although the nuclear reaction network includes a few thousand heavy nuclei, only limited reaction flow through light - mass nuclei near the stability line has been used in those studies. however, in a viable scenario of the r - process in neutrino - driven winds, the initial condition is a high - entropy hot plasma consisting of neutrons, protons, and electron - positron pairs experiencing an intense flux of neutrinos. in such environments light - mass nuclei as well as heavy nuclei are expected to play important roles in the production of seed nuclei and r - process elements. thus, we have extended our fully implicit nuclear reaction network so that it includes all nuclei up to the neutron drip line for z $ \ leq 10 $, in addition to a larger network for z $ \ geq 10 $. in the present nucleosynthesis study, we utilize a wind model of massive sneii explosions to study the effects of this extended network. we find that a new nuclear - reaction flow path opens in the very light neutron - rich region. this new nuclear reaction flow can change the final heavy - element abundances by as much as an order of magnitude.
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arxiv:astro-ph/0107368
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in this paper we present s3r - net, the self - supervised shadow removal network. the two - branch wgan model achieves self - supervision relying on the unify - and - adaptphenomenon - it unifies the style of the output data and infers its characteristics from a database of unaligned shadow - free reference images. this approach stands in contrast to the large body of supervised frameworks. s3r - net also differentiates itself from the few existing self - supervised models operating in a cycle - consistent manner, as it is a non - cyclic, unidirectional solution. the proposed framework achieves comparable numerical scores to recent selfsupervised shadow removal models while exhibiting superior qualitative performance and keeping the computational cost low.
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arxiv:2404.12103
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we study how the sizes and radial profiles of galaxies vary with wavelength, by fitting sersic functions simultaneously to imaging in nine optical and near - infrared bands. to quantify the wavelength dependence of effective radius we use the ratio, $ \ mathcal { r } $, of measurements in two restframe bands. the dependence of sersic index on wavelength, $ \ mathcal { n } $, is computed correspondingly. vulcani et al. ( 2014 ) have demonstrated that different galaxy populations present sharply contrasting behaviour in terms of $ \ mathcal { r } $ and $ \ mathcal { n } $. here we study the luminosity dependence of this result. we find that at higher luminosities, early - type galaxies display a more substantial decrease in effective radius with wavelength, whereas late - types present a more pronounced increase in sersic index. the structural contrast between types thus increases with luminosity. by considering samples at different redshifts, we demonstrate that lower data quality reduces the apparent difference between the main galaxy populations. however, our conclusions remain robust to this effect. we show that accounting for different redshift and luminosity selections partly reconciles the size variation measured by vulcani et al. with the weaker trends found by other recent studies. dividing galaxies by visual morphology confirms the behaviour inferred using morphological proxies, although the sample size is greatly reduced. finally, we demonstrate that varying dust opacity and disc inclination can account for features of the joint distribution of $ \ mathcal { r } $ and $ \ mathcal { n } $ for late - type galaxies. however, dust does not appear to explain the highest values of $ \ mathcal { r } $ and $ \ mathcal { n } $. the bulge - disc nature of galaxies must also contribute to the wavelength - dependence of their structure.
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arxiv:1509.06756
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thin films of aluminum hafnium nitride ( al $ _ { 1 - x } $ hf $ _ { x } $ n ) were synthesized via reactive magnetron sputtering for hf contents up to $ x $ = 0. 13. x - ray diffraction showed a single $ c $ - axis oriented wurtzite phase for all films. hard x - ray photoelectron spectroscopy demonstrated homogeneous al : hf distribution through the thin films and confirmed their insulating character. a collection of complementary tests showed unambiguous polarization inversion, and thus ferroelectricity in multiple samples. current density vs. electric field hysteresis measurements showed distinct ferroelectric switching current peaks, the piezoelectric coefficient d $ _ { 33, f, meas } $ measured using a double beam laser interferometer ( dbli ) showed a reversal in sign with similar magnitude, and anisotropic wet etching confirmed field - induced polarization inversion. this demonstrates the possibility of using tetravalent - - and not just trivalent - - alloying elements to enable ferroelectricity in aln - based thin films, highlighting the compositional flexibility of ferroelectricity in wurtzites and greatly expanding the chemistries that can be considered for future devices.
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arxiv:2503.08816
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a physically - informed continuum crystal plasticity model is presented to elucidate the deformation mechanisms and dislocation evolution in body - centered - cubic ( bcc ) tantalum widely used as a key structural material for mechanical and thermal extremes. we show our unified structural modeling framework informed by mesoscopic dislocation dynamics simulations is capable of capturing salient features of the large inelastic behavior of tantalum at quasi - static ( 10 $ ^ { - 3 } $ s $ ^ { - 1 } $ ) to extreme strain rates ( 5000 s $ ^ { - 1 } $ ) and at room temperature and higher ( 873k ) at both single - and polycrystal levels. we also present predictive capabilities of our model for microstructural evolution in the material. to this end, we investigate the effects of dislocation interactions on slip activities, instability and strain - hardening behavior at the single crystal level. furthermore, ex situ measurements on crystallographic texture evolution and dislocation density growth are carried out for the polycrystal tantalum specimens at increasing strains. numerical simulation results also support that our modeling framework is capable of capturing the main features of the polycrystal behavior over a wide range of strains, strain rates and temperatures. the theoretical, experimental and numerical results at both single - and polycrystal levels provide critical insight into the underlying physical pictures for micro - and macroscopic responses and their relations in this important class of refractory bcc materials undergoing severe inelastic deformations.
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arxiv:2109.15214
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standard type theory, stt, tells us that $ b ^ n ( a ^ m ) $ is well - formed iff $ n = m + 1 $. however, linnebo and rayo ( 2012 ) have advocated for the use of cumulative type theory, ctt, which has more relaxed type - restrictions : according to ctt, $ b ^ \ beta ( a ^ \ alpha ) $ is well - formed iff $ \ beta > \ alpha $. in this paper, we set ourselves against ctt. we begin our case by arguing against linnebo & rayo ' s claim that ctt sheds new philosophical light on set theory. we then argue that, while ctt ' s type - restrictions are unjustifiable, the type - restrictions imposed by stt are justified by a fregean semantics. what is more, this fregean semantics provides us with a principled way to resist linnebo & rayo ' s semantic argument for ctt. we end by examining an alternative approach to cumulative types due to florio & jones ( 2021 ) ; we argue that their theory is best seen as a misleadingly formulated version of stt.
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arxiv:2108.04582
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spike timing - dependent plasticity ( stdp ) is a promising substitute to backpropagation for local training of spiking neural networks ( snns ) on neuromorphic hardware. stdp allows snns to address classification tasks by combining unsupervised stdp for feature extraction and supervised stdp for classification. unsupervised stdp is usually employed with winner - takes - all ( wta ) competition to learn distinct patterns. however, wta for supervised stdp classification faces unbalanced competition challenges. in this paper, we propose a method to effectively implement wta competition in a spiking classification layer employing first - spike coding and supervised stdp training. we introduce the neuronal competition group ( ncg ), an architecture that improves classification capabilities by promoting the learning of various patterns per class. an ncg is a group of neurons mapped to a specific class, implementing intra - class wta and a novel competition regulation mechanism based on two - compartment thresholds. we incorporate our proposed architecture into spiking classification layers trained with state - of - the - art supervised stdp rules. on top of two different unsupervised feature extractors, we obtain significant accuracy improvements on image recognition datasets such as cifar - 10 and cifar - 100. we show that our competition regulation mechanism is crucial for ensuring balanced competition and improved class separation.
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arxiv:2410.17066
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this volume contains the proceedings of rule 2009 : the tenth international workshop on rule - based programming. it took place in june 28th 2009, brasilia, brazil, as a satellite event of rdp 2009. the first rule workshop was held in montreal in 2000, and subsequent editions took place in firenze, pittsburgh, valencia, aachen, nara, seattle, paris, and hagenberg.
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arxiv:1003.5758
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we give a new proof of the fact that, near a turning point of the frozen boundary, the vertical tiles in a uniformly random lozenge tiling of a large sawtooth domain are distributed like the eigenvalues of a gue random matrix. our argument uses none of the standard tools of integrable probability. in their place, it uses a combinatorial interpretation of the harish - chandra / itzykson - zuber integral as a generating function for desymmetrized hurwitz numbers.
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arxiv:1407.7578
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encryption - based cyber threats continue to evolve, leveraging increasingly sophisticated cryptographic techniques to evade detection and persist within compromised systems. a hierarchical classification framework designed to analyze structural cryptographic properties provides a novel approach to distinguishing malicious encryption from legitimate cryptographic operations. by systematically decomposing encryption workflows into hierarchical layers, the classification method enhances the ability to recognize distinct patterns across diverse threat variants, reducing the dependence on predefined signatures that often fail against rapidly mutating threats. the study examines how cryptographic feature mapping facilitates improved classification accuracy, highlighting the role of entropy, key exchange mechanisms, and algorithmic dependencies in distinguishing harmful encryption activities. through experimental validation, the framework demonstrated a high degree of precision across multiple attack families, outperforming conventional classification techniques while maintaining computational efficiency suitable for large - scale cybersecurity applications. the layered structural analysis further enhances forensic investigations, enabling security analysts to dissect encryption workflows to trace attack origins and identify commonalities across different campaigns. the methodology strengthens proactive threat mitigation efforts, offering a scalable and adaptable solution that accounts for both known and emerging encryption - based cyber threats. comparative evaluations illustrate the advantages of structural decomposition in mitigating false positives and negatives, reinforcing the reliability of cryptographic signature classification in real - world security environments.
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arxiv:2501.19120
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gallium selenide ( gase ) is an efficient nonlinear crystal for electro - optic ( eo ) sampling in the multi - terahertz ( thz ) frequency range. however, the lattice resonance at several thz frequencies hampers broadband eo sampling, resulting in distorted pulse waveforms. in this work, we experimentally evaluated the frequency - dependent response function in eo sampling, considering the effects of phonons, phase mismatch, and gate pulse waveforms. the phonon effect is described using an effective faust - henry coefficient, which was determined to be $ - 0. 21 \ pm 0. 02 $. the corrected field amplitude of multi - thz pulses aligns with additional measurements of average power and a beam diameter. the successful compensation of the frequency characteristics in gase will contribute to a more accurate evaluation of multi - thz transients.
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arxiv:2505.07242
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the surface tension of partially wetting droplets deforms soft substrates. these deformations are usually localized to a narrow region near the contact line, forming a so - called ` elastocapillary ridge. ' when a droplet slides along a substrate, the movement of the elastocapillary ridge dissipates energy in the substrate and slows the droplet down. previous studies have analyzed isotropically spreading droplets and found that the advancing contact line ` surfs ' the elastocapillary ridge, with a velocity determined by a local balance of capillary forces and bulk rheology. here, we experimentally explore the dynamics of a droplet sliding across soft substrates. at low velocities, the contact line is nearly circular, and dissipation increases logarithmically with speed. at higher droplet velocities, the contact line adopts a bullet - like shape, and the dissipation levels off. at the same time, droplets shed a pair of ` elastocapillary rails ' that fade away slowly behind it. these results suggest that droplets favor sliding along a stationary ridge over surfing atop a translating one.
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arxiv:2409.00280
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we compute the decay constants of the lowest ccbar - states with quantum numbers j ( pc ) = 0 ( - + ) [ eta _ c ], 1 ( - - ) [ j / psi ], and 1 ( + - ) [ hc ] by using lattice qcd and qcd sum rules. we consider the coupling of j / psi to both the vector and tensor currents. lattice qcd results are obtained from the unquenched ( nf = 2 ) simulations using twisted mass qcd at four lattice spacings, allowing us to take the continuum limit. on the qcd sum rule side we use the moment sum rules. the results are then used to discuss the rate of eta _ c - - > gamma gamma decay, and to comment on the factorization in b - - > x k decays, with x being either eta _ c or j / psi.
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arxiv:1312.2858
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this paper concerns the derivation of radiative transfer equations for acoustic waves propagating in a randomly fluctuating half - space in the weak - scattering regime, and the study of boundary effects through an asymptotic analysis of the wigner transform of the wave solution. these radiative transfer equations allow to model the transport of wave energy density, taking into account the scattering by random heterogeneities. the approach builds on the method of images, where the half - space problem is extended to a full - space, with two symmetric sources and an even map of mechanical properties. two contributions to the total energy density are then identified : one similar to the energy density propagation in a full - space, for which the resulting lack of statistical stationarity of the medium properties has no leading - order effect ; and one supported within one wavelength of the boundary, which describes interference effects between the waves produced by the two symmetric sources. in the case of a homogeneous neumann boundary conditions, this boundary effect yields a doubling of the intensity, and in the case of homogeneous dirichlet boundary conditions, a canceling of that intensity.
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arxiv:2211.17007
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relational data are usually highly incomplete in practice, which inspires us to leverage side information to improve the performance of community detection and link prediction. this paper presents a bayesian probabilistic approach that incorporates various kinds of node attributes encoded in binary form in relational models with poisson likelihood. our method works flexibly with both directed and undirected relational networks. the inference can be done by efficient gibbs sampling which leverages sparsity of both networks and node attributes. extensive experiments show that our models achieve the state - of - the - art link prediction results, especially with highly incomplete relational data.
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arxiv:1706.04289
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this is the writeup of the talk i gave at the yukawa international symposium at kyoto, japan on june 29, 1999. the talk summarizes the present status of the close limit approximation for colliding black holes.
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arxiv:gr-qc/9909021
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in a recent breakthrough paper [ m. braverman, a. garg, d. pankratov, and o. weinstein, from information to exact communication, stoc ' 13 ] braverman et al. developed a local characterization for the zero - error information complexity in the two party model, and used it to compute the exact internal and external information complexity of the 2 - bit and function, which was then applied to determine the exact asymptotic of randomized communication complexity of the set disjointness problem. in this article, we extend their results on and function to the multi - party number - in - hand model by proving that the generalization of their protocol has optimal internal and external information cost for certain distributions. our proof has new components, and in particular it fixes some minor gaps in the proof of braverman et al.
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arxiv:1703.07833
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here we study the global existence of ` hairy ' dyonic black hole and dyon solutions to four dimensional, anti - de sitter einstein - yang - mills theories for a general simply - connected and semisimple gauge group $ g $, for so - called topologically symmetric systems, concentrating here on the regular case. we generalise here cases in the literature which considered purely magnetic spherically symmetric solutions for a general gauge group and topological dyonic solutions for $ \ mathfrak { su } ( n ) $. we are able to establish the global existence of non - trivial solutions to all such systems, both near existing embedded solutions and as $ | \ lambda | \ rightarrow \ infty $. in particular, we can identify non - trivial solutions where the gauge field functions have no zeroes, which in the $ \ mathfrak { su } ( n ) $ case proved important to stability. we believe that these are the most general analytically proven solutions in 4d anti - de sitter einstein - yang - mills systems to date.
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arxiv:1707.08281
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to probe the star formation ( sf ) process, we present a multi - wavelength study of iras 05480 + 2545 ( hereafter i05480 + 2545 ). analysis of herschel data reveals a massive clump ( m _ clump ~ 1875 msun ; peak n ( h _ 2 ) ~ 4. 8 x 10 ^ { 22 } cm ^ { - 2 } ; a _ v ~ 51 mag ) containing the 6. 7 ghz methanol maser and i05480 + 2545, which is also depicted in a temperature range of 18 - 26 k. several noticeable parsec - scale filaments are detected in the herschel 250 microns image and seem to be radially directed to the massive clump. it resembles more of a " hub - filament " system. deeply embedded young stellar objects ( ysos ) have been identified using the 1 - 5 microns photometric data, and a significant fraction of ysos and their clustering are spatially found toward the massive clump, revealing the intense sf activities. an infrared counterpart ( irc ) of the maser is investigated in the spitzer 3. 6 - 4. 5 microns images. the irc does not appear point - like source and is most likely associated with the molecular outflow. based on the 1. 4 ghz and halpha continuum images, the ionized emission is absent toward the irc, indicating that the massive clump harbors an early phase of massive protostar before the onset of an ultracompact h ii region. together, the i05480 + 2545 is embedded in a very similar " hub - filament " system to those seen in rosette molecular cloud. the outcome of the present work indicates the role of filaments in the formation of the massive star - forming clump and cluster of ysos, which might help channel material to the central hub configuration and the clump / core.
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arxiv:1706.03714
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ob associations play an important role in galactic evolution, though their origins and dynamics remain poorly studied, with only a small number of systems analysed in detail. in this paper we revisit the existence and membership of the cygnus ob associations. we find that of the historical ob associations only cyg ob2 and ob3 stand out as real groups. we search for new ob stars using a combination of photometry, astrometry, evolutionary models and an sed fitting process, identifying 4680 probable ob stars with a reliability of $ > $ 90 \ %. from this sample we search for ob associations using a new and flexible clustering technique, identifying 6 new ob associations. two of these are similar to the associations cyg ob2 and ob3, though the others bear no relationship to any existing systems. we characterize the properties of the new associations, including their velocity dispersions and total stellar masses, all of which are consistent with typical values for ob associations. we search for evidence of expansion and find that all are expanding, albeit anistropically, with stronger and more significant expansion in the direction of galactic longitude. we also identify two large - scale ( 160 pc and 25 km s $ ^ { - 1 } $ ) kinematic expansion patterns across the cygnus region, each including three of our new associations, and attribute this to the effects of feedback from a previous generation of stars. this work highlights the need to revisit the existence and membership of the historical ob associations, if they are to be used to study their properties and dynamics.
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arxiv:2109.07499
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in this paper we reverse engineer the sony imx219pq image sensor, otherwise known as the raspberry pi camera v2. 0. we provide a visual reference for pixel non - uniformity by analysing variations in transistor length, microlens optic system and in the photodiode. we use these measurements to demonstrate irregularities at the microscopic level and link this to the signal variation measured as pixel non - uniformity used for unique identification of discrete image sensors.
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arxiv:1901.03807
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the usual modelling of the syllogisms of the organon by a calculus of classes does not include relations. aristotle may however have envisioned them in the first two books as the category of relatives, where he allowed them to compose with themselves. composition is the main operation in combinatory logic, which therefore offers itself for a new kind of modelling. the resulting calculus includes also composition of predicates by logical connectives.
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arxiv:2007.04252
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actuating robotic systems with multiple degrees of freedom ( dof ) traditionally requires numerous motors, leading to increased size, weight, cost, and power consumption. mechanical multiplexing offers a solution by enabling a single actuator to control multiple dof. however, existing multiplexers have either been limited to electrically controlled time - based multiplexing that control one dof at a time or have relied on mechanical switching to control multiple dof simultaneously. there is a strong need for a system that can perform electrically controlled multiplexing for both time - based and simultaneous control of multiple dof. this study introduces a novel electrostatic capstan clutch - based mechanical multiplexer that enables high - force, single - motor control of multiple dof. here, we show that our system achieves both single - input - single - output ( siso ) and single - input - multipleoutput ( simo ) actuation, allowing bidirectional control and position holding with minimal power consumption. each output can actuate a 22. 24 n load, limited by clutch performance, up to 5 cm. the number of outputs and actuation length is currently limited by the length of the drive shaft. we demonstrate the integration of our system into a 4 - dof commercial robotic hand using a single motor. these findings show that electrostatic clutchbased multiplexing provides a scalable and energy - efficient design solution for high - dof robotic platforms, opening new possibilities for lightweight and power - efficient actuation in robotics.
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arxiv:2501.08469
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we study sums of powers of fibonacci and lucas polynomials of the form $ % \ sum _ { n = 0 } ^ { q } f _ { tsn } ^ { k } ( x ) $ and $ \ sum _ { n = 0 } ^ { q } l _ { tsn } ^ { k } % ( x ) $, where $ s, t, k $ are given natural numbers, together with the corresponding alternating sums $ \ sum _ { n = 0 } ^ { q } ( - 1 ) ^ { n } f _ { tsn } ^ { k } ( x ) $ and $ \ sum _ { n = 0 } ^ { q } ( - 1 ) ^ { n } l _ { tsn } ^ { k } ( x ) $. we give sufficient conditions on the parameters $ s, t, k $ for express these sums as linear combinations of certain $ s $ - fibopolynomials.
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arxiv:1206.7103
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debugging is an essential part of software maintenance and evolution since it allows software developers to analyze program execution step by step. understanding a program is required to fix potential flaws, alleviate bottlenecks, and implement new desired features. thus, software developers spend a large percentage of their time validating and debugging software, resulting in high software maintenance and evolution cost. we aim to reduce this cost by providing a novel visual debugging tool to software developers to foster program comprehension during debugging. our debugging tool visualizes program execution information graphically as an object diagram and is fully integrated into the popular java development environment intellij idea. moreover, the object diagram allows interactions to explore program execution information in more detail. a demonstration of our tool is available at https : / / www. youtube. com / watch? v = lu _ ogotwerk.
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arxiv:2404.12932
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bi2te3 compound has been theoretically predicted ( 1 ) to be a topological insulator, and its topologically non - trivial surface state with a single dirac cone has been observed in photoemission experiments ( 2 ). here we report that superconductivity ( tc ^ ~ 3k ) can be induced in bi2te3 as - grown single crystal ( with hole - carriers ) via pressure. the first - principles calculations show that the electronic structure under pressure remains to be topologically nontrivial, and the dirac - type surface states can be well distinguished from bulk states at corresponding fermi level. the proximity effect between superconducting bulk states and dirac - type surface state could generate majorana fermions on the surface. we also discuss the possibility that the bulk state could be a topological superconductor.
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arxiv:1009.3691
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the kepler mission has provided a wealth of data, revealing new insights in time - domain astronomy. however, kepler ' s single band - pass has limited studies to a single wavelength. in this work we build a data - driven, pixel - level model for the pixel response function ( prf ) of kepler targets, modeling the image data from the spacecraft. our model is sufficiently flexible to capture known detector effects, such as non - linearity, intra - pixel sensitivity variations, and focus change. in theory, the shape of the kepler prf should also be weakly wavelength dependent, due to optical chromatic aberration and wavelength dependent detector response functions. we are able to identify these predicted shape changes to the prf using the residuals between kepler data and our model. in this work, we show that these prf changes correspond to wavelength variability in kepler targets using a small sample of eclipsing binaries. using our model, we demonstrate that pixel - level light curves of eclipsing binaries show variable eclipse depths, ellipsoidal modulation and limb darkening. these changes at the pixel level are consistent with multi - wavelength photometry. our work suggests each pixel in the kepler data of a single target has a different effective wavelength, ranging from $ \ approx $ 550 - 750 $ nm $. in this proof of concept, we demonstrate our model, and discuss possible use cases for the wavelength dependent pixel response function of kepler. these use cases include characterizing variable systems, and vetting exoplanet discoveries at the pixel level. the chromatic prf of kepler is due to weak wavelength dependence in the optical systems and detector of the telescope, and similar chromatic prfs are expected in other similar telescopes, notably the nasa tess telescope.
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arxiv:2102.00044
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{ let $ { \ cal x } $ be a self - dual p - polynomial association scheme. then there are at most 12 diagonal matrices $ t $ such that $ ( pt ) ^ 3 = i $. moreover, all of the solutions for the classical infinite families of such schemes ( including the hamming scheme ) are classified.
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arxiv:math/9406225
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domain generalization aims to learn a generalizable model from a known source domain for various unknown target domains. it has been studied widely by domain randomization that transfers source images to different styles in spatial space for learning domain - agnostic features. however, most existing randomization uses gans that often lack of controls and even alter semantic structures of images undesirably. inspired by the idea of jpeg that converts spatial images into multiple frequency components ( fcs ), we propose frequency space domain randomization ( fsdr ) that randomizes images in frequency space by keeping domain - invariant fcs ( difs ) and randomizing domain - variant fcs ( dvfs ) only. fsdr has two unique features : 1 ) it decomposes images into difs and dvfs which allows explicit access and manipulation of them and more controllable randomization ; 2 ) it has minimal effects on semantic structures of images and domain - invariant features. we examined domain variance and invariance property of fcs statistically and designed a network that can identify and fuse difs and dvfs dynamically through iterative learning. extensive experiments over multiple domain generalizable segmentation tasks show that fsdr achieves superior segmentation and its performance is even on par with domain adaptation methods that access target data in training.
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arxiv:2103.02370
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let $ g $ be a finite $ p $ - group whose derived subgroup $ g ' $ can be generated by $ 2 $ elements. if $ g ' $ is abelian, guralnick proved that every element of $ g ' $ is a commutator. in this paper, we prove that the condition that $ g ' $ should be abelian is not needed. even more, we prove that every element of $ g ' $ is a commutator of the form $ [ x, g ] $ for a fixed $ x \ in g $.
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arxiv:1709.10422
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we investigate the lhc discovery potential of r - parity violating supersymmetric models with a right - handed selectron or smuon as the lightest supersymmetric particle ( lsp ). these lsps arise naturally in r - parity violating minimal supergravity models. we classify the hadron collider signatures and perform for the first time within these models a detailed signal over background analysis. we develop an inclusive three - lepton search and give prospects for a discovery at a center - of - mass energy of 7 tev as well as 14 tev. there are extensive parameter regions which the lhc can already test with 7 tev and an integrated luminosity of 1 inverse femtobarn. we also propose a method for the mass reconstruction of the supersymmetric particles within our models at 14 tev.
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arxiv:1102.3189
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we present a terrain traversability mapping and navigation system ( tns ) for autonomous excavator applications in an unstructured environment. we use an efficient approach to extract terrain features from rgb images and 3d point clouds and incorporate them into a global map for planning and navigation. our system can adapt to changing environments and update the terrain information in real - time. moreover, we present a novel dataset, the complex worksite terrain ( cwt ) dataset, which consists of rgb images from construction sites with seven categories based on navigability. our novel algorithms improve the mapping accuracy over previous sota methods by 4. 17 - 30. 48 % and reduce mse on the traversability map by 13. 8 - 71. 4 %. we have combined our mapping approach with planning and control modules in an autonomous excavator navigation system and observe 49. 3 % improvement in the overall success rate. based on tns, we demonstrate the first autonomous excavator that can navigate through unstructured environments consisting of deep pits, steep hills, rock piles, and other complex terrain features.
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arxiv:2109.06250
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robots will bring search and rescue ( sar ) in disaster response to another level, in case they can autonomously take over dangerous sar tasks from humans. a main challenge for autonomous sar robots is to safely navigate in cluttered environments with uncertainties, while avoiding static and moving obstacles. we propose an integrated control framework for sar robots in dynamic, uncertain environments, including a computationally efficient heuristic motion planning system that provides a nominal ( assuming there are no uncertainties ) collision - free trajectory for sar robots and a robust motion tracking system that steers the robot to track this reference trajectory, taking into account the impact of uncertainties. the control architecture guarantees a balanced trade - off among various sar objectives, while handling the hard constraints, including safety. the results of various computer - based simulations, presented in this paper, showed significant out - performance ( of up to 42. 3 % ) of the proposed integrated control architecture compared to two commonly used state - of - the - art methods ( rapidly - exploring random tree and artificial potential function ) in reaching targets ( e. g., trapped victims in sar ) safely, collision - free, and in the shortest possible time.
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arxiv:2505.03283
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density estimation is one of the most widely used methods for crowd counting in which a deep learning model learns from head - annotated crowd images to estimate crowd density in unseen images. typically, the learning performance of the model is highly impacted by the accuracy of the annotations and inaccurate annotations may lead to localization and counting errors during prediction. a significant amount of works exist on crowd counting using perfectly labelled datasets but none of these explore the impact of annotation errors on the model accuracy. in this paper, we investigate the impact of imperfect labels ( both noisy and missing labels ) on crowd counting accuracy. we propose a system that automatically generates imperfect labels using a deep learning model ( called annotator ) which are then used to train a new crowd counting model ( target model ). our analysis on two crowd counting models and two benchmark datasets shows that the proposed scheme achieves accuracy closer to that of the model trained with perfect labels showing the robustness of crowd models to annotation errors.
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arxiv:2212.01450
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a generalized master equation ( gme ) is used to study the thermoelectric currents through a quantum dot in both the transient and steady - state regime. the two semi - infinite leads are kept at the same chemical potential but at different temperatures to produce a thermoelectric current which has a varying sign depending on the chemical potential. the coulomb interaction between the electrons in the sample is included via the exact diagonalization method. we observe a saw - teeth like profile of the current alternating with plateaus of almost zero current. our calculations go beyond the linear response with respect to the temperature gradient, but are compatible with known results for the thermopower in the linear response regime.
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arxiv:1303.3160
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for equation p $ _ i ^ 2 $, the second member in the p $ _ i $ hierarchy, we prove existence of various degenerate solutions depending on the complex parameter $ t $ and evaluate the asymptotics in the complex $ x $ plane for $ | x | \ to \ infty $ and $ t = o ( x ^ { 2 / 3 } ) $. using this result, we identify the most degenerate solutions $ u ^ { ( m ) } ( x, t ) $, $ \ hat u ^ { ( m ) } ( x, t ) $, $ m = 0,..., 6 $, called { \ em tritronqu \ ' ee }, describe the quasi - linear stokes phenomenon and find the large $ n $ asymptotics of the coefficients in a formal expansion of these solutions. we supplement our findings by a numerical study of the tritronqu \ ' ee solutions.
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arxiv:1306.6161
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salient object detection increasingly receives attention as an important component or step in several pattern recognition and image processing tasks. although a variety of powerful saliency models have been intensively proposed, they usually involve heavy feature ( or model ) engineering based on priors ( or assumptions ) about the properties of objects and backgrounds. inspired by the effectiveness of recently developed feature learning, we provide a novel deep image saliency computing ( disc ) framework for fine - grained image saliency computing. in particular, we model the image saliency from both the coarse - and fine - level observations, and utilize the deep convolutional neural network ( cnn ) to learn the saliency representation in a progressive manner. specifically, our saliency model is built upon two stacked cnns. the first cnn generates a coarse - level saliency map by taking the overall image as the input, roughly identifying saliency regions in the global context. furthermore, we integrate superpixel - based local context information in the first cnn to refine the coarse - level saliency map. guided by the coarse saliency map, the second cnn focuses on the local context to produce fine - grained and accurate saliency map while preserving object details. for a testing image, the two cnns collaboratively conduct the saliency computing in one shot. our disc framework is capable of uniformly highlighting the objects - of - interest from complex background while preserving well object details. extensive experiments on several standard benchmarks suggest that disc outperforms other state - of - the - art methods and it also generalizes well across datasets without additional training. the executable version of disc is available online : http : / / vision. sysu. edu. cn / projects / disc.
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arxiv:1511.04192
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we describe how the notion of optical beam shifts ( including the spatial and angular goos - h \ " anchen shift and imbert - federov shift ) can be understood as a classical analogue of a quantum measurement of the polarization state of a paraxial beam by its transverse amplitude distribution. under this scheme, complex quantum weak values are interpreted as spatial and angular shifts of polarized scalar components of the reflected beam. this connection leads us to predict an extra spatial shift for beams with a radially - varying phase dependence.
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arxiv:1204.0327
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research on differentiable scene representations is consistently moving towards more efficient, real - time models. recently, this has led to the popularization of splatting methods, which eschew the traditional ray - based rendering of radiance fields in favor of rasterization. this has yielded a significant improvement in rendering speeds due to the efficiency of rasterization algorithms and hardware, but has come at a cost : the approximations that make rasterization efficient also make implementation of light transport phenomena like reflection and refraction much more difficult. we propose a novel scene representation which avoids these approximations, but keeps the efficiency and reconstruction quality of splatting by leveraging a decades - old efficient volumetric mesh ray tracing algorithm which has been largely overlooked in recent computer vision research. the resulting model, which we name radiant foam, achieves rendering speed and quality comparable to gaussian splatting, without the constraints of rasterization. unlike ray traced gaussian models that use hardware ray tracing acceleration, our method requires no special hardware or apis beyond the standard features of a programmable gpu.
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arxiv:2502.01157
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for two graphs $ g $ and $ h $, write $ g \ stackrel { \ mathrm { rbw } } { \ longrightarrow } h $ if $ g $ has the property that every \ emph { proper } colouring of its edges yields a \ emph { rainbow } copy of $ h $. we study the thresholds for such so - called \ emph { anti - ramsey } properties in randomly perturbed dense graphs, which are unions of the form $ g \ cup \ mathbb { g } ( n, p ) $, where $ g $ is an $ n $ - vertex graph with edge - density at least $ d > 0 $, and $ d $ is independent of $ n $. in a companion article, we proved that the threshold for the property $ g \ cup \ mathbb { g } ( n, p ) \ stackrel { \ mathrm { rbw } } { \ longrightarrow } k _ \ ell $ is $ n ^ { - 1 / m _ 2 ( k _ { \ left \ lceil \ ell / 2 \ right \ rceil } ) } $, whenever $ \ ell \ geq 9 $. for smaller $ \ ell $, the thresholds behave more erratically, and for $ 4 \ le \ ell \ le 7 $ they deviate downwards significantly from the aforementioned aesthetic form capturing the thresholds for \ emph { large } cliques. in particular, we show that the thresholds for $ \ ell \ in \ { 4, 5, 7 \ } $ are $ n ^ { - 5 / 4 } $, $ n ^ { - 1 } $, and $ n ^ { - 7 / 15 } $, respectively. for $ \ ell \ in \ { 6, 8 \ } $ we determine the threshold up to a $ ( 1 + o ( 1 ) ) $ - factor in the exponent : they are $ n ^ { - ( 2 / 3 + o ( 1 ) ) } $ and $ n ^ { - ( 2 / 5 + o ( 1 ) ) } $, respectively. for $ \ ell = 3 $, the threshold is $ n ^ { - 2 } $ ; this follows from a more general result about odd cycles in our companion paper.
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arxiv:2006.00588
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high fidelity generation of two - qubit gates is important for quantum computation, since such gates are components of popular universal sets of gates. here we consider the problem of high fidelity generation of two - qubit c - not and c - phase ( with a detailed study of c - z ) gates in presence of the environment. we consider the general situation when qubits are manipulated by coherent and incoherent controls ; the latter is used to induce generally time - dependent decoherence rates. for estimating efficiency of optimization methods for high fidelity generation of these gates, we study quantum control landscapes which describe the behaviour of the fidelity as a function of the controls. for this, we generate and analyze the statistical distributions of best objective values obtained by incoherent gradient ascent pulse engineering ( ingrape ) approach. we also apply ingrape and stochastic zero - order method to numerically estimate minimal infidelity values. the results are different from the case of single - qubit gates and indicate a smooth trap - free behaviour of the fidelity.
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arxiv:2405.14069
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temporal action detection ( tad ) is a fundamental video understanding task that aims to identify human actions and localize their temporal boundaries in videos. although this field has achieved remarkable progress in recent years, further progress and real - world applications are impeded by the absence of a standardized framework. currently, different methods are compared under different implementation settings, evaluation protocols, etc., making it difficult to assess the real effectiveness of a specific technique. to address this issue, we propose \ textbf { opentad }, a unified tad framework consolidating 16 different tad methods and 9 standard datasets into a modular codebase. in opentad, minimal effort is required to replace one module with a different design, train a feature - based tad model in end - to - end mode, or switch between the two. opentad also facilitates straightforward benchmarking across various datasets and enables fair and in - depth comparisons among different methods. with opentad, we comprehensively study how innovations in different network components affect detection performance and identify the most effective design choices through extensive experiments. this study has led to a new state - of - the - art tad method built upon existing techniques for each component. we have made our code and models available at https : / / github. com / sming256 / opentad.
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arxiv:2502.20361
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background : the presence of nuclear ground states with stable reflection - asymmetric shapes is supported by rich experimental evidence. theoretical surveys of odd - multipolarity deformations predict the existence of pear - shaped isotopes in several fairly localized regions of the nuclear landscape in the vicinity of near - lying single - particle shells with $ \ delta \ ell = \ delta j = 3 $. purpose : we analyze the role of isoscalar, isovector, neutron - proton, neutron - neutron, and proton - proton multipole interaction energies in inducing the onset of reflection - asymmetric ground - state deformations. methods : the calculations are performed in the framework of axial reflection - asymmetric hartree - fock - bogoliubov theory using two skyrme energy density functionals and density - dependent pairing force. results : we show that reflection - asymmetric ground - state shapes of atomic nuclei are driven by the odd - multipolarity neutron - proton ( or isoscalar ) part of the nuclear interaction energy. this result is consistent with the particle - vibration picture, in which the main driver of octupole instability is the isoscalar octupole - octupole interaction giving rise to large $ e3 $ polarizability.
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arxiv:2012.06500
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##lativistic effects manifested in the four classical test experiments of einstein ' s general relativity ( gr ), in direct agreement with the experiments and the predictions given based on gr.
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arxiv:physics/0612096
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the self - dual chern - simons solitons under the influence of the quantum potential are considered. the single - valuedness condition for an arbitrary integer number $ n \ ge 0 $ of solitons leads to quantization of chern - simons coupling constant $ \ kappa = m { e ^ { 2 } \ over g } $, and the integer strength of quantum potential $ s = 1 - m ^ { 2 } $. as we show, the jackiw - pi model corresponds to the first member ( m = 1 ) of our hierarchy of the chern - simons gauged nonlinear schr \ " odinger models, admitting self - dual solitons. new type of exponentially localized chern - simons solitons for the bloch electrons near the hyperbolic energy band boundary are found.
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arxiv:hep-th/9906104
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it has been recently pointed out, that nonlocal nambu - - jona - lasinio models, may present unphysical thermodynamical behavior like negative pressure and oscillating entropy. here we show how these thermodynamic instabilities can be related to the analytical structure of the poles of the quark propagator in the model. the analysis is carried out for two different regulators and we show, in each case, how the instabilities are related to the pressence of highly unstable poles. we also argue that the softening of these instabilities by the inclusion of the polyakov loop is related to the effect the latter has on the poles of the propagator.
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arxiv:1409.0500
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we have computed finite temperature corrections to the electron - hadron scattering cross sections. these are based upon the renormalized electron mass and the modified density of states due to the presence of a background thermal bath. it is found that the electron - hadron thermal transport scattering cross section can be much larger than the zero temperature one. in the case of electron - neutron transport scattering, we find \ sigma _ { ne } ( t ) / \ sigma _ { ne } ( t = 0 ) \ simeq 5 at t \ simeq 0. 1 mev.
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arxiv:astro-ph/9804090
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we develop representation theoretic techniques to construct three dimensional non - semisimple topological quantum field theories which model homologically truncated topological b - twists of abelian gaiotto - witten theory with linear matter. our constructions are based on relative modular structures on the category of weight modules over an unrolled quantization of a lie superalgebra. the lie superalgebra, originally defined by gaiotto and witten, is associated to a complex symplectic representation of a metric abelian lie algebra. the physical theories we model admit alternative realizations as chern - simons - rozansky - witten theories and supergroup chern - simons theories and include as particular examples global forms of $ \ mathfrak { gl } ( 1 \ vert 1 ) $ - chern - simons theory and toral chern - simons theory. fundamental to our approach is the systematic incorporation of non - genuine line operators which source flat connections for the topological flavour symmetry of the theory.
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arxiv:2401.16192
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in this paper, we propose a sampling mechanism for adaptive diffusion networks that adaptively changes the amount of sampled nodes based on mean - squared error in the neighborhood of each node. it presents fast convergence during transient and a significant reduction in the number of sampled nodes in steady state. besides reducing the computational cost, the proposed mechanism can also be used as a censoring technique, thus saving energy by reducing the amount of communication between nodes. we also present a theoretical analysis to obtain lower and upper bounds for the number of network nodes sampled in steady state.
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arxiv:2007.06456
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the swift - hohenberg ( sh ) and phase - field crystal ( pfc ) models are minimal yet powerful approaches for studying phenomena such as pattern formation, collective order, and defects via smooth order parameters. they are based on a free - energy functional that inherently includes elasticity effects. this study addresses how gradient elasticity ( ge ), a theory that accounts for elasticity effects at microscopic scales by introducing additional characteristic lengths, is incorporated into sh and pfc models. after presenting the fundamentals of these theories and models, we first calculate the characteristic lengths for various lattice symmetries in an approximated setting. we then discuss numerical simulations of stress fields at dislocations and comparisons with analytic solutions within first and second strain - gradient elasticity. effective ge characteristic lengths for the elastic fields induced by dislocations are found to depend on the free - energy parameters in the same manner as the phase correlation length, thus unveiling how they change with the quenching depth. the findings presented in this study enable a thorough discussion and analysis of small - scale elasticity effects in pattern formation and crystalline systems using sh and pfc models and, importantly, complete the elasticity analysis therein. additionally, we provide a microscopic foundation for ge in the context of order - disorder phase transitions.
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arxiv:2312.08154
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reframing a negative into a positive thought is at the crux of several cognitive approaches to mental health and psychotherapy that could be made more accessible by large language model - based solutions. such reframing is typically non - trivial and requires multiple rationalization steps to uncover the underlying issue of a negative thought and transform it to be more positive. however, this rationalization process is currently neglected by both datasets and models which reframe thoughts in one step. in this work, we address this gap by augmenting open - source datasets for positive text rewriting with synthetically - generated socratic rationales using a novel framework called \ textsc { socraticreframe }. socraticreframe uses a sequence of question - answer pairs to rationalize the thought rewriting process. we show that such socratic rationales significantly improve positive text rewriting for different open - source llms according to both automatic and human evaluations guided by criteria from psychotherapy research. we validate our framework and the synthetic rationalizations with expert judgements from domain experts and psychology students in an irb - approved annotation study. our findings highlight the potential of utilizing the synergy between llm reasoning and established psychotherapy techniques to build assistive solutions for reframing negative thoughts.
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arxiv:2403.03029
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the rapid development of large language models ( llms ) demonstrates remarkable multilingual capabilities in natural language processing, attracting global attention in both academia and industry. to mitigate potential discrimination and enhance the overall usability and accessibility for diverse language user groups, it is important for the development of language - fair technology. despite the breakthroughs of llms, the investigation into the multilingual scenario remains insufficient, where a comprehensive survey to summarize recent approaches, developments, limitations, and potential solutions is desirable. to this end, we provide a survey with multiple perspectives on the utilization of llms in the multilingual scenario. we first rethink the transitions between previous and current research on pre - trained language models. then we introduce several perspectives on the multilingualism of llms, including training and inference methods, information retrieval, model security, multi - domain with language culture, and usage of datasets. we also discuss the major challenges that arise in these aspects, along with possible solutions. besides, we highlight future research directions that aim at further enhancing llms with multilingualism. the survey aims to help the research community address multilingual problems and provide a comprehensive understanding of the core concepts, key techniques, and latest developments in multilingual natural language processing based on llms.
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arxiv:2405.10936
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the coherent information concept is used to analyze a variety of simple quantum systems. coherent information was calculated for the information decay in a two - level atom in the presence of an external resonant field, for the information exchange between two coupled two - level atoms, and for the information transfer from a two - level atom to another atom and to a photon field. the coherent information is shown to be equal to zero for all full - measurement procedures, but it completely retains its original value for quantum duplication. transmission of information from one open subsystem to another one in the entire closed system is analyzed to learn quantum information about the forbidden atomic transition via a dipole active transition of the same atom. it is argued that coherent information can be used effectively to quantify the information channels in physical systems where quantum coherence plays an important role.
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arxiv:quant-ph/9912113
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a two - dimensional ( 2d ) mathematical model of quadratically distorted ( qd ) grating is established with the principles of fraunhofer diffraction and fourier optics. discrete sampling and bisection algorithm are applied for finding numerical solution of the diffraction pattern of qd grating. this 2d mathematical model allows the precise design of qd grating and improves the optical performance of simultaneous multiplane imaging system.
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arxiv:1710.00645
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as a principled dimension reduction technique, factor models have been widely adopted in social science, economics, bioinformatics, and many other fields. however, in high - dimensional settings, conducting a ' correct ' bayesianfactor analysis can be subtle since it requires both a careful prescription of the prior distribution and a suitable computational strategy. in particular, we analyze the issues related to the attempt of being " noninformative " for elements of the factor loading matrix, especially for sparse bayesian factor models in high dimensions, and propose solutions to them. we show here why adopting the orthogonal factor assumption is appropriate and can result in a consistent posterior inference of the loading matrix conditional on the true idiosyncratic variance and the allocation of nonzero elements in the true loading matrix. we also provide an efficient gibbs sampler to conduct the full posterior inference based on the prior setup from rockova and george ( 2016 ) and a uniform orthogonal factor assumption on the factor matrix.
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arxiv:2006.01055
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