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recent studies focusing on the use of radio data in indirect dark matter detection have led to a set of highly competitive limits on the wimp annihilation cross - section, especially in light of high - resolution data from instruments like askap and meerkat. in this work we present an analysis of radio observations of the rxc j0225. 1 - 2928 galaxy cluster, taken from the recent meerkat galaxy cluster legacy survey public data release. we adopt a robust morphological analysis of this source that allows us to derive a set of upper - limits on the annihilation cross - section, and in our most constraining scenario these results are comparable to the most stringent limits yet found in the literature.
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arxiv:2303.00684
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we compute by supersymmetric localization the expectation values of half - bps ' t hooft line operators in $ \ mathcal { n } = 2 $ $ u ( n ) $, $ so ( n ) $ and $ usp ( n ) $ gauge theories on $ s ^ 1 \ times \ mathbb { r } ^ 3 $ with an $ \ omega $ - deformation. we evaluate the non - perturbative contributions due to monopole screening by calculating the supersymmetric indices of the corresponding supersymmetric quantum mechanics, which we obtain by realizing the gauge theories and the ' t hooft operators using branes and orientifolds in type ii string theories.
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arxiv:2012.12275
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scene, as the crucial unit of storytelling in movies, contains complex activities of actors and their interactions in a physical environment. identifying the composition of scenes serves as a critical step towards semantic understanding of movies. this is very challenging - - compared to the videos studied in conventional vision problems, e. g. action recognition, as scenes in movies usually contain much richer temporal structures and more complex semantic information. towards this goal, we scale up the scene segmentation task by building a large - scale video dataset moviescenes, which contains 21k annotated scene segments from 150 movies. we further propose a local - to - global scene segmentation framework, which integrates multi - modal information across three levels, i. e. clip, segment, and movie. this framework is able to distill complex semantics from hierarchical temporal structures over a long movie, providing top - down guidance for scene segmentation. our experiments show that the proposed network is able to segment a movie into scenes with high accuracy, consistently outperforming previous methods. we also found that pretraining on our moviescenes can bring significant improvements to the existing approaches.
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arxiv:2004.02678
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we present an achievable rate region for the general three user discrete memoryless broadcast channel, based on nested coset codes. we characterize 3 - to - 1 discrete broadcast channels, a class of broadcast channels for which the best known coding technique \ footnote { we henceforth refer to this as marton ' s coding for three user discrete broadcast channel. }, which is obtained by a natural generalization of that proposed by marton for the general two user discrete broadcast channel, is strictly sub - optimal. in particular, we identify a novel 3 - to - 1 discrete broadcast channel for which marton ' s coding is \ textit { analytically } proved to be strictly suboptimal. we present achievable rate regions for the general 3 - to - 1 discrete broadcast channels, based on nested coset codes, that strictly enlarge marton ' s rate region for the aforementioned channel. we generalize this to present achievable rate region for the general three user discrete broadcast channel. combining together marton ' s coding and that proposed herein, we propose the best known coding technique, for a general three user discrete broadcast channel.
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arxiv:1207.3146
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the purpose of this note is to prove a lower bound for the estimation of the memory parameter of a stationary long memory process. the memory parameter is defined here as the index of regular variation of the spectral density at 0. the rates of convergence obtained in the literature assume second order regular variation of the spectral density at zero. in this note, we do not make this assumption, and show that the rates of convergence in this case can be extremely slow. we prove that the log - periodogram regression ( gph ) estimator achieves the optimal rate of convergence for gaussian long memory processes.
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arxiv:0906.0180
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there are two permutation groups that they share the same character table of order 1344. we take up natural representations on 8 and 14 letters respectively. the purpose of this paper is to examine the semi - simple structure of centralizing algebras in the tensor representation.
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arxiv:2412.00001
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it is commonly believed that logical states of quantum error - correcting codes have to be highly entangled such that codes capable of correcting more errors require more entanglement to encode a qubit. here we show that this belief may or may not be true depending on a particular code. to this end, we characterize a tradeoff between the code distance $ d $ quantifying the number of correctable errors, and geometric entanglement of logical states quantifying their maximal overlap with product states or more general " topologically trivial " states. the maximum overlap is shown to be exponentially small in $ d $ for three families of codes : ( 1 ) low - density parity check ( ldpc ) codes with commuting check operators, ( 2 ) stabilizer codes, and ( 3 ) codes with a constant encoding rate. equivalently, the geometric entanglement of any logical state of these codes grows at least linearly with $ d $. on the opposite side, we also show that this distance - entanglement tradeoff does not hold in general. for any constant $ d $ and $ k $ ( number of logical qubits ), we show there exists a family of codes such that the geometric entanglement of some logical states approaches zero in the limit of large code length.
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arxiv:2405.01332
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removing optical and atmospheric blur from galaxy images significantly improves galaxy shape measurements for weak gravitational lensing and galaxy evolution studies. this ill - posed linear inverse problem is usually solved with deconvolution algorithms enhanced by regularisation priors or deep learning. we introduce a so - called " physics - informed deep learning " approach to the point spread function ( psf ) deconvolution problem in galaxy surveys. we apply algorithm unrolling and the plug - and - play technique to the alternating direction method of multipliers ( admm ), in which a neural network learns appropriate hyperparameters and denoising priors from simulated galaxy images. we characterise the time - performance trade - off of several methods for galaxies of differing brightness levels as well as our method ' s robustness to systematic psf errors and network ablations. we show an improvement in reduced shear ellipticity error of 38. 6 % ( snr = 20 ) / 45. 0 % ( snr = 200 ) compared to classic methods and 7. 4 % ( snr = 20 ) / 33. 2 % ( snr = 200 ) compared to modern methods.
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arxiv:2211.01567
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the aim of these notes is to show how the magnetic calculus developed in \ cite { mp, imp1, imp2, mpr, lmr } permits to give a new information on the nature of the coefficients of the expansion of the trace of a function of the magnetic schr \ " odinger operator whose existence was established in \ cite { hr2 }.
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arxiv:1005.1795
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dynamic models have been successfully used in producing estimates of hiv epidemics at the national level due to their epidemiological nature and their ability to estimate prevalence, incidence, and mortality rates simultaneously. recently, hiv interventions and policies have required more information at sub - national levels to support local planning, decision making and resource allocation. unfortunately, many areas lack sufficient data for deriving stable and reliable results, and this is a critical technical barrier to more stratified estimates. one solution is to borrow information from other areas within the same country. however, directly assuming hierarchical structures within the hiv dynamic models is complicated and computationally time - consuming. in this paper, we propose a simple and innovative way to incorporate hierarchical information into the dynamical systems by using auxiliary data. the proposed method efficiently uses information from multiple areas within each country without increasing the computational burden. as a result, the new model improves predictive ability and uncertainty assessment.
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arxiv:2401.04753
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currently there is great interest in the outcomes and astrophysical implications of mergers of double degenerate binaries. in a commonly adopted approximation, the components of such binaries are represented by polytropes with an index n = 3 / 2. we present detailed comparisons of stellar mass - transfer and merger simulations of polytropic binaries that have been carried out using two very different numerical algorithms - - - a finite - volume " grid " code and a smoothed - particle hydrodynamics ( sph ) code. we find that there is agreement in both the ultimate outcomes of the evolutions and the intermediate stages if the initial conditions for each code are chosen to match as closely as possible. we find that even with closely matching initial setups, the time it takes to reach a concordant evolution differs between the two codes because the initial depth of contact cannot be matched exactly. there is a general tendency for sph to yield higher mass transfer rates and faster evolution to the final outcome. we also present comparisons of simulations calculated from two different energy equations : in one series we assume a polytropic equation of state and in the other series an ideal gas equation of state. in the latter series of simulations an atmosphere forms around the accretor which can exchange angular momentum and cause a more rapid loss of orbital angular momentum. in the simulations presented here, the effect of the ideal equation of state is to de - stabilize the binary in both sph and grid simulations, but the effect is more pronounced in the grid code.
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arxiv:1702.03562
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2h nmr spin - lattice relaxation and line - shape analyses are performed to study the temperature - dependent dynamics of water in the hydration shells of myoglobin, elastin, and collagen.
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arxiv:0904.4424
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in this paper, we study nijenhuis operators on leibniz algebras. we discuss the relationship of nijenhuis operators with rota - baxter operators and modified rota - baxter operators on leibniz algebras. we define a representation theory of nijenhuis leibniz algebras and construct a cohomology theory. next, we define a one - parameter formal deformation theory of nijenhuis leibniz algebras and study infinitesimals, rigidity, and equivalences along the line of gerstenhaber deformation theory. as an application of our cohomology theory, we show that our cohomology is deformation cohomology and study abelian extensions of such algebras.
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arxiv:2306.06428
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the cosmic expansion is computed for various dynamical vacuum models $ \ lambda ( h ) $ and confronted to the cosmic microwave background ( cmb ) power spectrum from planck. we also combined cmb in a joint analysis with other probes in order to place constraints on the cosmological parameters of the dynamical vacuum models. we find that all $ \ lambda ( h ) $ models are very efficient and in very good agreement with the data. considering that the interaction term of the dark sector is given in terms of matter and radiation densities, we find that the corresponding $ \ lambda ( h ) $ model shows a small but non - zero deviation from $ \ lambda $ cosmology, nevertheless the confidence level is close to $ \ sim 2. 5 \ sigma $.
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arxiv:1810.12902
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newtonian, lagrangian, and hamiltonian dynamical systems are well formalized mathematically. they give rise to geometric structures describing motion of a point in smooth manifolds. riemannian metric is a different geometric structure formalizing concepts of length and angle. the interplay of riemannian metric and its metric connection with mechanical structures produces some features which are absent in the case of general ( non - riemannian ) manifolds. the aim of present paper is to discuss these features and develop special language for describing newtonian, lagrangian, and hamiltonian dynamical systems in riemannian manifolds.
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arxiv:math/0107212
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high perceptual quality and low distortion degree are two important goals in image restoration tasks such as super - resolution ( sr ). most of the existing sr methods aim to achieve these goals by minimizing the corresponding yet conflicting losses, such as the $ \ ell _ 1 $ loss and the adversarial loss. unfortunately, the commonly used gradient - based optimizers, such as adam, are hard to balance these objectives due to the opposite gradient decent directions of the contradictory losses. in this paper, we formulate the perception - distortion trade - off in sr as a multi - objective optimization problem and develop a new optimizer by integrating the gradient - free evolutionary algorithm ( ea ) with gradient - based adam, where ea and adam focus on the divergence and convergence of the optimization directions respectively. as a result, a population of optimal models with different perception - distortion preferences is obtained. we then design a fusion network to merge these models into a single stronger one for an effective perception - distortion trade - off. experiments demonstrate that with the same backbone network, the perception - distortion balanced sr model trained by our method can achieve better perceptual quality than its competitors while attaining better reconstruction fidelity. codes and models can be found at https : / / github. com / csslc / ea - adam } { https : / / github. com / csslc / ea - adam.
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arxiv:2312.15408
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we derive the equations of motion that arise from the one - loop effective action for the geometry of 3 + 1 dimensional quantum branes in the ikkt matrix model. these equations are cast into the form of generalized einstein equations, with extra contributions from dilaton and axionic fields, as well as a novel anharmonicity tensor c _ { \ mu \ nu } capturing the classical yang - mills - type action. the resulting gravity theory approximately reduces to general relativity in some regime, but differs significantly at cosmic scales, leading to an asymptotically flat flwr cosmological evolution governed by the classical action.
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arxiv:2312.01317
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this document is written as an academic exercise, with the goal of exploring the feasibility of writing a white paper in accordance with regulation ( eu ) 2023 / 1114 ( mica ). it is meant as a proof of concept ( poc ) illustrating a concrete application of the requirements of mica. like the mica white papers poc shared by esma, this document is solely for the purposes of the poc, to inform the public as to how a crypto - asset white paper could work, inspire public debate and feedback, and enhance the public conversation around the implementation of eu regulations.
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arxiv:2403.10583
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in this paper we establish three basic equations for a general soliton structure on the riemannian manifold $ ( m, <, > ) $. we then draw some geometric conclusions with the aid of the maximum principle.
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arxiv:1009.1480
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this study analyzes heat waves ( hws ), air pollution ( ap ) episodes, and compound hw and ap events ( ce ) in the urban environment and provides a comparison between events in urban areas ( uas ) and rural areas ( ras ). a 1 - km gridded daily minimum temperature dataset and a 1 - km gridded daily pm2. 5 concentration dataset were used along with geospatial data to characterize events by their frequency, intensity in heat, intensity in pollution, and duration. the greatest differences between uas and ras in frequency, heat intensity, pollution intensity, and duration for all events were seen in the west and southwest regions. for both uas and ras, it was found that hws were the most frequent, intense, and longest lasting in the west and southwest regions, ap episodes were the most frequent and longest lasting in the northeast, ohio valley, and southeast regions, and ap episodes were the most intense in the northern rockies and plains and upper midwest regions. it was concluded that hws ( ap episodes ) had a greater impact on ces than ap episodes ( hws ) in regions with more prominent hws ( ap episodes ).
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arxiv:2307.15296
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in this paper, we demonstrate the lhc discovery potential of new charged vector boson $ w _ 1 ^ { \ pm } $ predicted by the minimal higgsless model in the process $ pp \ to w _ 1 ^ { \ pm } qq ^ { \ prime } \ to w ^ { \ pm } z ^ 0qq ^ \ prime \ to \ ell ^ { \ pm } \ ell ^ + \ ell ^ - \ nu qq ^ { \ prime } ( \ ell = e, \ mu ) $ by analyzing the generator level events of the signal and backgrounds. the generator for the signal $ pp \ to { w _ 1 } ^ { \ pm } qq ^ \ prime \ to w ^ { \ pm } z ^ 0qq ^ \ prime $ at tree level is developed with the minimal higgsless model and then interfaced with pythia for the parton showers and hadronization. the backgrounds are produced with pythia and acermc. we give integrated luminosities required to discover 5 $ \ sigma $ signal as a function of $ w _ 1 ^ { \ pm } $ mass.
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arxiv:0905.2336
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transcription of the genetic message encoded chemically in the sequence of the dna template is carried out by a molecular machine called rna polymerase ( rnap ). backward or forward slippage of the nascent rna with respect to the dna template strand give rise to a transcript that is, respectively, longer or shorter than the corresponding template. we model a rnap as a " tape - copying turing machine " ( tctm ) where the dna template is the input tape while the nascent rna strand is the output tape. although the tctm always steps forward the process is assumed to be stochastic that has a probability of occurrence per unit time. the time taken by a tctm for each single successful forward stepping on the input tape, during which the output tape suffers lengthening or shortening by $ n $ units because of backward or forward slippage, is a random variable ; we report some of the statistical characteristics of this time by using the formalism for calculation of the distributions of { \ it first - passage time }. the results are likely to find applications in the analysis of experimental data on " programmed " transcriptional error caused by transcriptional slippage which is a mode of " recoding " of genetic information.
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arxiv:1703.10409
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we present an extended worked example of the computation of the tropical superpotential considered by carl - - pumperla - - siebert. in particular we consider an affine manifold associated to the complement of a non - singular genus one plane curve, and calculate the wall and chamber decomposition determined by the gross - - siebert algorithm. using the results of carl - - pumperla - - siebert we determine the tropical superpotential, via broken line counts, in every chamber of this decomposition. the superpotential defines a laurent polynomial in every chamber, which we demonstrate to be identical to the laurent polynomials predicted by coates - - corti - - galkin - - golyshev - - kaspzryk to be mirror to $ \ mathbb { p } ^ 2 $.
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arxiv:1703.07620
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we show that current and imminent underground detectors are capable of precision astrometry of dark matter. first we show that galactic dark matter velocity distributions can be obtained from reconstructed tracks of dark matter scattering on multiple nuclei during transit ; using the liquid scintillator neutrino detector sno + as an example, we find that the dark matter velocity vector can be reconstructed event - by - event with such a small uncertainty, that the precision of dark matter astrometry will be limited mainly by statistics. we then determine the number of dark matter events required to determine the dispersion speed, escape speed, and velocity anisotropies of the local dark matter halo, and also find that with as few as $ \ mathcal { o } ( 10 ) $ events, dark matter signals may be discriminated from potential backgrounds arising as power - law distributions. finally, we discuss the prospects of dark matter astrometry at other liquid scintillator detectors, dark matter experiments, and the recently proposed mathusla detector.
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arxiv:1910.05380
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we consider holomorphic foliations of dimension $ k > 1 $ and codimension $ \ geq 1 $ in the projective space $ \ mathbb { p } ^ n $, with a compact connected component of the kupka set. we prove that, if the transversal type is linear with positive integers eigenvalues, then the foliation consist on the fibers of a rational fibration. as a corollary, if $ \ mathcal { f } $ is a foliation such that $ dim ( \ mathcal { f } ) \ geq cod ( \ mathcal { f } ) + 2 $ and has transversal type diagonal with different eigenvalues, then the kupka component $ k $ is a complete intersection and we get the same conclusion. the same conclusion holds if the kupka set is a complete intersection and has radial transversal type. finally, as an application, we find a normal form for non integrable codimension one distributions on $ \ mathbb { p } ^ { n } $.
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arxiv:1408.7020
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numerous recent measurements of kaon decays are described, with an emphasis on results offering constraints on chiral perturbation theory calculations. an up - to - date estimate of | vus | f + ( 0 ) based on semileptonic kaon decay rates is presented.
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arxiv:hep-ex/0611057
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we will consider completely positive maps defined on tensor products of von neumann algebras and taking values in the algebra of bounded operators on a hilbert space and particularly certain convex subsets of the set of such maps. we show that when one of the marginal maps of such a map is an extremal point, then the marginals uniquely determine the map. we will further prove that when both of the marginals are extremal, then the whole map is extremal. we show that this general result is the common source of several well - known results dealing with, e. g., jointly measurable observables. we also obtain new insight especially in the realm of quantum instruments and their marginal observables and channels.
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arxiv:1209.5933
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we study the conditions for disk galaxies to produce superbubbles that can break out of the disk and produce a galactic wind. we argue that the threshold surface density of supernovae rate for seeding a wind depends on the ability of superbubble energetics to compensate for radiative cooling. we first adapt kompaneets formalism for expanding bubbles in a stratified medium to the case of continuous energy injection and include the effects of radiative cooling in the shell. with the help of hydrodynamic simulations, we then study the evolution of superbubbles evolving in stratified disks with typical disk parameters. we identify two crucial energy injection rates that differ in their effects, the corresponding breakout ranging from being gentle to a vigorous one. ( a ) superbubbles that break out of the disk with a mach number of order 2 - 3 correspond to an energy injection rate of order 10 ^ { - 4 } erg cm ^ { - 2 } s ^ { - 1 }, which is relevant for disk galaxies with synchrotron emitting gas in the extra - planar regions. ( b ) a larger energy injection threshold, of order 10 ^ { - 3 } erg cm ^ { - 2 } s ^ { - 1 }, or equivalently, a star formation surface density of \ sim 0. 1 solar mass yr ^ { - 1 } kpc ^ { - 2 }, corresponds to superbubbles with a mach number \ sim 5 - 10. while the milder superbubbles can be produced by large ob associations, the latter kind requires super - starclusters. these derived conditions compare well with observations of disk galaxies with winds and the existence of multiphase halo gas. furthermore, we find that contrary to the general belief that superbubbles fragment through rayleigh - taylor ( rt ) instability when they reach a vertical height of order the scale height, the superbubbles are first affected by thermal instability for typical disk parameters and that rt instability takes over when the shells reach a distance of approximately twice the scale height.
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arxiv:1303.2664
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this is an exposition of gauss ' s proof of descartes ' s rule of signs.
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arxiv:2205.04249
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up to now there has been no search for gravitational waves from the r - modes of neutron stars in spite of the theoretical interest in the subject. several oddities of r - modes must be addressed to obtain an observational result : the gravitational radiation field is dominated by the mass current ( gravitomagnetic ) quadrupole rather than the usual mass quadrupole, and the consequent difference in polarization affects detection statistics and parameter estimation. to astrophysically interpret a detection or upper limit it is necessary to convert the wave amplitude to an r - mode amplitude. also, it is helpful to know indirect limits on gravitational - wave emission to gauge the interest of various searches. here i address these issues, thereby providing the ingredients to adapt broad - band searches for continuous gravitational waves to obtain r - mode results. i also show that searches of existing data can already have interesting sensitivities to r - modes.
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arxiv:1006.1994
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based on a class of exactly solvable models of interacting bose and fermi liquids, we compute the single - particle propagators of these systems exactly for all wavelengths and energies and in any number of spatial dimensions. the field operators are expressed in terms of bose fields that correspond to displacements of the condensate in the bose case and displacements of the fermi sea in the fermi case. unlike some of the previous attempts, the present attempt reduces the answer for the spectral function in any dimension in both fermi and bose systems to quadratures. it is shown that when only the lowest order sea - displacement terms are included, the random phase approximation in its many guises is recovered in the fermi case, and bogoliubov ' s theory in the bose case. the momentum distribution is evaluated using two different approaches, exact diagonalisation and the equation of motion approach. the novelty being of course, the exact computation of single - particle properties including short wavelength behaviour.
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arxiv:hep-th/9706006
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magneto - optic photonic crystals ( mopc ) used in low dimension lasers whereby acting as faraday rotators capable of 45o rotation where insertion loos is compensated by photoluminescence effect are of significant interest. in low dimension sensors mopcs act as optical filters to selectively detect only lights at certain wavelengths. combined with the photoluminescence effect, sensors may be designed capable of detecting signals with extremely low intensity, thus high quantum efficiency. in this work, mopc with various erbium dopant concentrations, acting as photoluminescence center, were modelled under high pumping power regime associated to 0. 985 inversion population to identify the minimum erbium concentration and number of layers for the target 45 degrees fr, 0. 9 transmittance and minimal ellipticity at the resonance wavelength 1531nm. further optimization of magneto - optical ( mo ) properties versus the microcavity position within the mopc was investigated. an optimum multilayered configuration and composition was identified with a reduction in both erbium concentration and total thickness compared to what was reported previously without compromising the target mo properties.
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arxiv:1908.01637
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a model problem of the form - i \ epsilon y ' ' + q ( x ) y = \ lambda y, y ( - 1 ) = y ( 1 ) = 0, is associated with well - known in hydrodynamics orr - - sommerfeld operator. here ( \ lambda ) is the spectral parameter, ( \ epsilon ) is the small parameter which is proportional to the viscocity of the liquid and to the reciprocal of the reynolds number, and ( q ( x ) ) is the velocity of the stationary flow of the liquid in the channel ( | x | \ leqslant 1 ). we study the behaviour of the spectrum of the corresponding model operator as ( \ epsilon \ to 0 ) with monotonous analytic functions. we assert that the sets of the accumulation points of the spectra ( the limit spectral graphs ) of the model and the corresponding orr - - sommerfeld operators coincide as well as the main terms of the counting eigenvalue functions along the curves of the graphs. we prove the estimate from below for the resolvent of the operator ( l ( \ epsilon ) ) associated with the model problem. it turns out that the resolvent grows exponentially with respect to ( \ epsilon ) provided that the spectral parameter varies at some compacts belonging to the numerical range of the operator.
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arxiv:math/0306342
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the electronic structure and magnetic properties of the 2h - nbs $ _ 2 $ compound intercalated by cr, mn and fe, have been investigated by means of the korringa - kohn - rostoker ( kkr ) method. the calculations demonstrate easy plane magneto - crystalline anisotropy ( mca ) of cr $ _ { 1 / 3 } $ nbs $ _ 2 $ monotonously decreasing towards the curie temperature in line with the experimental results. the modification of the electronic structure results in a change of the easy axis from in - plane to out - of - plane. it is shown, that for cr $ _ { 1 / 3 } $ nbs $ _ 2 $ and mn $ _ { 1 / 3 } $ nbs $ _ 2 $ the in - plane mca and dzyaloshinskii - moriya interactions results in a helimagnetic structure along the hexagonal $ c $ axis, following the experimental observations. the negative exchange interactions in the fe $ _ { 1 / 3 } $ nbs $ _ 2 $ compound results in a non - collinear frustrated magnetic structure if the mca is not taken into account. it is shown, however, that a strong mca along the hexagonal $ c $ axis leads to a magnetic ordering referred to as an ordering of the third kind, which was observed experimentally.
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arxiv:1607.05738
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the advancement of large vision - language models ( lvlms ) has propelled their application in the medical field. however, medical lvlms ( med - lvlms ) encounter factuality challenges due to modality misalignment, where the models prioritize textual knowledge over visual input, leading to hallucinations that contradict information in medical images. previous attempts to enhance modality alignment in med - lvlms through preference optimization have inadequately mitigated clinical relevance in preference data, making these samples easily distinguishable and reducing alignment effectiveness. to address this challenge, we propose mmedpo, a novel multimodal medical preference optimization approach that considers the clinical relevance of preference samples to enhance med - lvlm alignment. mmedpo curates multimodal preference data by introducing two types of dispreference : ( 1 ) plausible hallucinations injected through target med - lvlms or gpt - 4o to produce medically inaccurate responses, and ( 2 ) lesion region neglect achieved through local lesion - noising, disrupting visual understanding of critical areas. we then calculate clinical relevance for each sample based on scores from multiple med - llms and visual tools, and integrate these scores into the preference optimization process as weights, enabling effective alignment. our experiments demonstrate that mmedpo significantly enhances factual accuracy in med - lvlms, achieving substantial improvements over existing preference optimization methods by averaging 14. 2 % and 51. 7 % across the med - vqa and report generation tasks. our code are available in https : / / github. com / aiming - lab / mmedpo.
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arxiv:2412.06141
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in this study, we present a novel extension to the klinkhamer vacuum - defect model by incorporating a fifth spatial dimension. this modification results in the formulation of a comprehensive five - dimensional wormhole space - time. crucially, this extension preserves its classification as a vacuum solution to the field equations, thereby automatically satisfying all energy conditions. we demonstrate that this five - dimensional vacuum - defect space - time can be expressed in a pure canonical form, and thus, locally reduces to five - dimensional minkowski space. finally, we explore the geodesic equations in the vicinity of this five - dimensional vacuum - defect wormhole, offering insights into its intriguing properties.
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arxiv:2308.11938
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eilenberg ' s variety theorem, a centerpiece of algebraic automata theory, establishes a bijective correspondence between varieties of languages and pseudovarieties of monoids. in the present paper this result is generalized to an abstract pair of algebraic categories : we introduce varieties of languages in a category c, and prove that they correspond to pseudovarieties of monoids in a closed monoidal category d, provided that c and d are dual on the level of finite objects. by suitable choices of these categories our result uniformly covers eilenberg ' s theorem and three variants due to pin, polak and reutenauer, respectively, and yields new eilenberg - type correspondences.
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arxiv:1501.05180
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we consider the initial value problem for the landau - lifshitz equation with helicity term ( chiral interaction term ), which arises from the dzyaloshinskii - moriya interaction. we prove that it is well - posed locally - in - time in the space $ \ bar { k } + h ^ s $ for $ s \ ge 3 $ with $ s \ in \ mathbb { z } $ and $ \ bar { k } = { } ^ t ( 0, 0, 1 ) $. we also show that if we further assume that the solution is homotopic to constant maps, then local well - posedness holds in the space $ \ bar { k } + h ^ s $ for $ s > 2 $ with $ s \ in \ mathbb { r } $. our proof is base on the analysis via the modified schr \ " odinger map equation.
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arxiv:2012.01535
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we experimentally investigated the splashing of dense suspension droplets impacting a solid surface, extending prior work to the regime where the viscosity of the suspending liquid becomes a significant parameter. the overall behavior can be described by a combination of two trends. the first one is that the splashing becomes favored when the kinetic energy of individual particles at the surface of a droplet overcomes the confinement produced by surface tension. this is expressed by a particle - based weber number $ we _ p $. the second is that splashing is suppressed by increasing the viscosity of the solvent. this is expressed by the stokes number $ st $, which influences the effective coefficient of restitution of colliding particles. we developed a phase diagram where the splashing onset is delineated as a function of both $ we _ p $ and $ st $. a surprising result occurs at very small stokes number, where not only splashing is suppressed but also plastic deformation of the droplet. this leads to a situation where droplets can bounce back after impact, an observation we are able to reproduce using discrete particle numerical simulations that take into account viscous interaction between particles and elastic energy.
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arxiv:1603.03186
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let $ a, b, c $ be subsets of an abelian group $ g $. a pair $ ( a, b ) $ is called a $ c $ - pair if $ a, b \ subset c $ and $ c $ is the direct sum of $ a $ and $ b $. the $ ( \ z _ { \ geq 0 } ) $ - pairs are characterized by de bruijn in 1950 and the $ ( \ z _ { \ geq 0 } ) ^ 2 $ - pairs are characterized by niven in 1971. in this paper, we characterize the $ ( \ z _ { \ geq 0 } ) ^ n $ - pairs for all $ n \ geq 1 $. we show that every $ ( \ z _ { \ geq 0 } ) ^ n $ - pair is characterized by a weighted tree if it is primitive, that is, it is not a cartesian product of a $ ( \ z _ { \ geq 0 } ) ^ p $ - pair and a $ ( \ z _ { \ geq 0 } ) ^ q $ - pair of lower dimensions.
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arxiv:2005.09204
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graded modal types systems and coeffects are becoming a standard formalism to deal with context - dependent computations where code usage plays a central role. the theory of program equivalence for modal and coeffectful languages, however, is considerably underdeveloped if compared to the denotational and operational semantics of such languages. this raises the question of how much of the theory of ordinary program equivalence can be given in a modal scenario. in this work, we show that coinductive equivalences can be extended to a modal setting, and we do so by generalising abramsky ' s applicative bisimilarity to coeffectful behaviours. to achieve this goal, we develop a general theory of ternary program relations based on the novel notion of a comonadic lax extension, on top of which we define a modal extension of abramsky ' s applicative bisimilarity ( which we dub modal applicative bisimilarity ). we prove such a relation to be a congruence, this way obtaining a compositional technique for reasoning about modal and coeffectful behaviours. but this is not the end of the story : we also establish a correspondence between modal program relations and program distances. this correspondence shows that modal applicative bisimilarity and ( a properly extended ) applicative bisimilarity distance coincide, this way revealing that modal program equivalences and program distances are just two sides of the same coin.
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arxiv:2103.03871
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region select is a game originally defined on a knot projection. in this paper, region select on an origami crease pattern is introduced and investigated. as an application, a new unlinking number associated with region crossing change is defined and discussed.
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arxiv:2402.00328
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hermes is a scientific mission composed of 3u nano - satellites dedicated to the detection and localization of high - energy astrophysical transients, with a distributed space architecture to form a constellation in earth orbits. the space segment hosts novel miniaturized detectors to probe the x - ray temporal emission of bright events, such as gamma - ray bursts ( grbs ), and the electromagnetic counterparts of gravitational wave events ( gwes ), playing a crucial role in future multi - messenger astrophysics. during operations, at least three instruments, separated by a minimum distance shall observe a common area of the sky to perform a triangulation of the observed event. an effective detection by the nano - satellite payload is achieved by guaranteeing a beneficial orbital and pointing configuration of the constellation. the design has to cope with the limitations imposed by small space systems, such as the lack of on - board propulsion and the reduced systems budgets. the paper describes the methodologies and the proposed strategies to overcome the mission limitations, while achieving a satisfactory constellation visibility of the sky throughout the mission duration. the mission design makes use of a high - fidelity orbit propagator, combined with an innovative mission analysis tool that estimates the scientific performances of the constellation. the influence of the natural relative motion, which is crucial to achieve an effective constellation configuration without on - board orbit control, is assessed. the presented methodology can be easily extended to any kind of distributed scientific space applications, as well as to constellations dedicated to earth and planetary observation. in addition, the visibility tool is applicable in the context of the constellation flight dynamics operations, yielding optimized results and pointing plans based on actual satellite orbital positions.
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arxiv:2010.05603
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the higgs mode associated with amplitude fluctuations of the superconducting gap in uniform superconductors usually is heavy, which makes its excitation and detection difficult. we report on the existence of a gapless higgs mode in the fulde - ferrell - larkin - ovchinnikov states. this feature is originated from the goldstone mode associated with the translation symmetry breaking. the existence of the gapless higgs mode is demonstrated by using both a phenomenological model and microscopic bardeen - cooper - schrieffer ( bcs ) theory. the gapless higgs mode can avoid the decay into other low energy excitations, which renders it stable and detectable.
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arxiv:2105.13422
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we present a systematic first - principles study of the phonon spectrum of hexagonal ymno3 in ferroelectric ( multiferroic ) phase. we investigated in detail the low - energy phonon modes, their dispersion, symmetry, as well as the infrared optical properties of the crystal and determined the phonon density of states.
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arxiv:1207.6565
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we analyze the quantum dynamics of periodically driven, disordered systems in the presence of long - range interactions. focusing on the stability of discrete time crystalline ( dtc ) order in such systems, we use a perturbative procedure to evaluate its lifetime. for 3d systems with dipolar interactions, we show that the corresponding decay is parametrically slow, implying that robust, long - lived dtc order can be obtained. we further predict a sharp crossover from the stable dtc regime into a regime where dtc order is lost, reminiscent of a phase transition. these results are in good agreement with the recent experiments utilizing a dense, dipolar spin ensemble in diamond [ nature 543, 221 - 225 ( 2017 ) ]. they demonstrate the existence of a novel, critical dtc regime that is stabilized not by many - body localization but rather by slow, critical dynamics. our analysis shows that the dtc response can be used as a sensitive probe of nonequilibrium quantum matter.
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arxiv:1703.04593
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malaria is one of the deadliest diseases in the world, every year millions of people become victims of this disease and many even lose their lives. medical professionals and the government could take accurate measures to protect the people only when the disease dynamics are understood clearly. in this work, we propose a compartmental model to study the dynamics of malaria. we consider the transmission rate dependent on temperature and altitude. we performed the steady state analysis on the proposed model and checked the stability of the disease - free and endemic steady state. an artificial neural network ( ann ) is applied to the formulated model to predict the trajectory of all five compartments following the mathematical analysis. three different neural network architectures namely artificial neural network ( ann ), convolution neural network ( cnn ), and recurrent neural network ( rnn ) are used to estimate these parameters from the trajectory of the data. to understand the severity of a disease, it is essential to calculate the risk associated with the disease. in this work, the risk is calculated using dynamic mode decomposition ( dmd ) from the trajectory of the infected people.
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arxiv:2409.00795
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in this paper we generalize our investigation of the unitarity of non - compact wznw models connected to hermitian symmetric spaces to the n = 1 world - sheet supersymmetric extension of these models. we will prove that these models have a unitary spectrum in a brst approach for antidominant highest weight representations if the level and weights of the gauged subalgebra are integers. we will find new critical string theories in 7 and 9 space - time dimensions.
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arxiv:0802.3578
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the yielding behavior of a sheared laponite suspension is investigated within a 1 mm gap under two different boundary conditions. no - slip conditions, ensured by using rough walls, lead to shear localization as already reported in various soft glassy materials. when apparent wall slip is allowed using a smooth geometry, the sample is shown to break up into macroscopic solid pieces that get slowly eroded by the surrounding fluidized material up to the point where the whole sample is fluid. such a drastic effect of boundary conditions on yielding suggests the existence of some macroscopic characteristic length that could be connected to cooperativity effects in jammed materials under shear.
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arxiv:0807.3274
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implementing fully automatic unmanned surface vehicles ( usvs ) monitoring water quality is challenging since effectively collecting environmental data while keeping the platform stable and environmental - friendly is hard to approach. to address this problem, we construct a usv that can automatically navigate an efficient path to sample water quality parameters in order to monitor the aquatic environment. the detection device needs to be stable enough to resist a hostile environment or climates while enormous volumes will disturb the aquaculture environment. meanwhile, planning an efficient path for information collecting needs to deal with the contradiction between the restriction of energy and the amount of information in the coverage region. to tackle with mentioned challenges, we provide a usv platform that can perfectly balance mobility, stability, and portability attributed to its special round - shape structure and redundancy motion design. for informative planning, we combined the tsp and cpp algorithms to construct an optimistic plan for collecting more data within a certain range and limiting energy restrictions. we designed a fish existence prediction scenario to verify the novel system in both simulation experiments and field experiments. the novel aquaculture environment monitoring system significantly reduces the burden of manual operation in the fishery inspection field. additionally, the simplicity of the sensor setup and the minimal cost of the platform enables its other possible applications in aquatic exploration and commercial utilization.
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arxiv:2211.00917
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the thermal evolution of neutron stars is affected by the elementary excitations that characterize the stellar matter. in particular, the low - energy excitations, with a spectrum linear in momentum, can play a major role in the emission and propagation of neutrinos. in this paper, we focus on the elementary modes in the region of proton superfluidity, where the neutron component is expected to have a very small or zero pairing gap. we study the overall spectral functions of protons, neutrons and electrons on the basis of the coulomb and nuclear interactions. this study is performed in the framework of the random phase approximation, generalized in order to describe the response of a superfluid system. the formalism we use ensures that the generalized ward ' s identities are satisfied. despite their relative small fraction, the protons turn out to modify the neutron spectral function as a consequence of the nuclear neutron - proton interaction. this effect is particularly evident at the lower density, just below the crust for a density close to the saturation value, while at increasing density the neutrons and the protons are mainly decoupled. the proton spectral function is characterized by a pseudo - goldstone mode below $ 2 \ delta $, twice the pairing gap, and a pair - breaking mode above $ 2 \ delta $. the latter merges in the sound mode of the normal phase at higher momenta. the neutron spectral function develops a collective sound mode only at the higher density. the electrons have a strong screening effect on the proton - proton interaction at the lower momenta, and decouple from the protons at higher momenta.
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arxiv:1708.03794
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small - scale explosive events or microflares occur throughout the chromospheric network of the sun. they are seen as sudden bursts of highly doppler shifted spectral lines of ions formed at temperatures in the range 2x10 ^ 4 - 5x10 ^ 5 k. they tend to occur near regions of cancelling photospheric magnetic fields and are thought to be directly associated with magnetic field reconnection. recent observations have revealed that they have a bi - directional jet structure reminiscent of petschek reconnection. in this paper compressible mhd simulations of the evolution of a current sheet to a steady petschek, jet - like configuration are computed using the versatile advection code. we obtain velocity profiles that can be compared with recent ultraviolet line profile observations. by choosing initial conditions representative of magnetic loops in the solar corona and chromosphere, it is possible to explain the fact that jets flowing outward into the corona are more extended and appear before jets flowing towards the chromosphere. this model can reproduce the high doppler shifted components of the line profiles but the brightening at low velocities, near the centre of the bi - directional jet, cannot be explained by this simple mhd model.
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arxiv:astro-ph/9901342
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unsupervised cross - lingual embeddings mapping has provided a unique tool for completely unsupervised translation even for languages with different scripts. in this work we use this method for the task of unsupervised cross - lingual matching of product classifications. our work also investigates limitations of unsupervised vector alignment and we also suggest two other techniques for aligning product classifications based on their descriptions : using hierarchical information and translations.
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arxiv:1809.07234
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in a unified viewpoint in quantum channel estimation, we compare the cramer - rao and the mini - max approaches, which gives the bayesian bound in the group covariant model. for this purpose, we introduce the local asymptotic mini - max bound, whose maximum is shown to be equal to the asymptotic limit of the mini - max bound. it is shown that the local asymptotic mini - max bound is strictly larger than the cramer - rao bound in the phase estimation case while the both bounds coincide when the minimum mean square error decreases with the order o ( 1 / n ). we also derive a sufficient condition for that the minimum mean square error decreases with the order o ( 1 / n ).
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arxiv:1003.4575
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prompt tuning learns soft prompts to condition frozen pre - trained language models ( plms ) for performing downstream tasks in a parameter - efficient manner. while prompt tuning has gradually reached the performance level of fine - tuning as the model scale increases, there is still a large performance gap between prompt tuning and fine - tuning for models of moderate and small scales ( typically less than 11b parameters ). in this paper, we empirically show that the trained prompt tokens can have a negative impact on a downstream task and thus degrade its performance. to bridge the gap, we propose a novel prompt tuning model with an extremely small scale ( xprompt ) under the regime of lottery tickets hypothesis. specifically, xprompt eliminates the negative prompt tokens at different granularity levels through a hierarchical structured pruning, yielding a more parameter - efficient prompt yet with a competitive performance. comprehensive experiments are carried out on superglue tasks, and the extensive results indicate that xprompt is able to close the performance gap at smaller model scales.
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arxiv:2210.04457
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a twisted higgs bundle on a k \ " ahler manifold $ x $ is a pair $ ( e, \ phi ) $ consisting of a holomorphic vector bundle $ e $ and a holomorphic bundle morphism $ \ phi \ colon m \ otimes e \ to e $ for some holomorphic vector bundle $ m $. such objects were first considered by hitchin when $ x $ is a curve and $ m $ is the tangent bundle of $ x $, and also by simpson for higher dimensional base. the hitchin - kobayashi correspondence for such pairs states that $ ( e, \ phi ) $ is polystable if and only if $ e $ admits a hermitian metric solving the hitchin equation. this correspondence is a powerful tool to decide whether there exists a solution of the equation, but it provides little information as to the actual solution. in this paper we study a quantization of this problem that is expressed in terms of finite dimensional data and balanced metrics that give approximate solutions to the hitchin equation. motivation for this study comes from work of donagi - - wijnholt on arxiv : 1104. 2610 concerning balanced metrics for the vafa - witten equations.
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arxiv:1401.7108
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the standard model indicates the realization of grand unified structures in nature, and can only be viewed as an effective theory below a higher energy cutoff. while the renormalizable standard model forbids proton decay mediating operators due to accidental global symmetries, many extensions of the standard model introduce such dimension four, five and six operators. furthermore, quantum gravity effects are expected to induce proton instability, indicating that the higher energy cutoff scale must be above 10 ^ { 16 } gev. quasi - realistic heterotic string models provide the arena to explore how perturbative quantum gravity affects the particle physics phenomenology. an appealing explanation for the proton longevity is provided by the existence of an abelian gauge symmetry that suppresses the proton decay mediating operators. additionally, such a low - scale u ( 1 ) symmetry should : allow the suppression of the left - handed neutrino masses by a seesaw mechanism ; allow fermion yukawa couplings to the electroweak higgs doublets ; be anomaly free ; be family universal. these requirements render the existence of such u ( 1 ) symmetries in quasi - realistic heterotic string models highly non - trivial. we demonstrate the existence of a u ( 1 ) symmetry that satisfies all of the above requirements in a class of left - right symmetric heterotic string models in the free fermionic formulation. the existence of the extra z ' in the energy range accessible to future experiments is motivated by the requirement of adequate suppression of proton decay mediation. we further show that while the extra u ( 1 ) forbids dimension four baryon number violating operators it allows dimension four lepton number violating operators and r - parity violation.
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arxiv:0704.1256
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this paper reports on the outcomes of a survey implemented in secondary schools. the survey identified the types of access and use of computers by students. it was found that the students had significant access to computers but they were not skilled in many features of computer use. computers were used for a range of activities, some educational and others recreational by some students. gender differences in computer use were not seen. the study highlights the changing scenario about uses of computer technology by students.
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arxiv:1406.6173
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this paper presents a flow - based methodology for capturing processes specified in business process modeling. the proposed methodology is demonstrated through re - modeling of an ibm blueworks case study. while the blueworks approach offers a well - proven tool in the field, this should not discourage workers from exploring other ways of thinking about effectively capturing processes. the diagrammatic representation presented here demonstrates a viable methodology in this context. it is hoped this explicit analysis of diverse fundamental approaches will benefit the research in the field and also advance current practices.
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arxiv:1704.02973
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the ideal ( tagged resp. ) triangulation of bounded surface with marked points are associated with skew - symmetric ( skew - symmetrizable ) exchange matrices. an algo - rithm is established to decompose the graph associated to such matrix. there are finite many graph with non - unique decomposition. we find all such graphs and their decompositions. in addition, we also find the associated ideal ( tagged ) triangulations to different decompositions.
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arxiv:1112.1008
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the ntmpy code package allows for simulating the one - dimensional thermal response of multilayer samples after optical excitation, as in a typical pump - probe experiment. several python routines are combined and optimized to solve coupled heat diffusion equations in one dimension, on arbitrary piecewise homogeneous material stacks, in the framework of the so - called three - temperature model. the energy source deposited in the material is modelled as a light pulse of arbitrary cross - section and temporal profile. a transfer matrix method enables the calculation of realistic light absorption in presence of scattering interfaces as in multilayer samples. the open source code is fully object - oriented to enable a user - friendly and intuitive interface for adjusting the physically relevant input parameters. here, we describe the mathematical background of the code, we lay out the workflow, and we validate the functionality of our package by comparing it to commercial software, as well as to experimental transient reflectivity data recorded in a pump - probe experiment with femtosecond light pulses.
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arxiv:2002.04559
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flavor - dependent neutrino emission is critical to the evolution of a supernova and its neutrino signal. in the dense anisotropic interior of the star, neutrino - neutrino forward - scattering can lead to fast collective neutrino oscillations, which has striking consequences. we present a theory of fast flavor depolarization, explaining how neutrino flavor differences become smaller, i. e., depolarize, due to diffusion to smaller angular scales. we show that transverse relaxation determines the epoch of this irreversible depolarization. we give a method to compute the depolarized fluxes, presenting an explicit formula for simple initial conditions, which can be a crucial input for supernova theory and neutrino phenomenology.
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arxiv:2009.03337
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in this article, by considering $ t = ( t _ 1, \ dots, t _ d ) $, an $ d $ - tuple of commuting contractions on a hilbert space $ \ mathcal { h } $, we study $ t $ - toeplitz operators which consists of bounded operators $ x $ on $ \ mathcal { h } $ such that \ [ t _ i ^ * xt _ i = x \ ] for all $ i = 1, \ dots, d $. we show that any positive $ t $ - toeplitz operator can be factorized in terms of an isometric pseudo - extension of $ t $. a similar factorization result is also obtained for positive pure lower $ t $ - toeplitz operators. however, the latter factorization is obtained in terms of a special type of isometric pseudo - extension of $ t $, and a certain difference has been observed between the case $ d = 2 $ and $ d > 2 $. in a more general context, by considering $ d $ - tuples of commuting contractions $ s $ and $ t $, we also study $ ( s, t ) $ - toeplitz operators.
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arxiv:2207.08183
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mgb2 monofilamentary nickel - sheated tapes and wires were fabricated by means of the ex - situ powder - in - tube method using either high - energy ball milled and low temperature synthesized powders. all sample were sintered at 920 c in ar flow. the milling time and the revolution speed were tuned in order to maximize the critical current density in field ( jc ) : the maximum jc value of 6 x 10e4 a / cm2 at 5 k and 4 t was obtained corresponding to the tape prepared with powders milled for 144h at 180rpm. vorious synthesis temperature were also investigated ( 730 - 900 c ) finding a best jc value for the wire prepared with powders synthesized at 745 c. we speculate that this optimal temperature is due to the fluidifying effect of unreacted magnesium content before the sintering process which could better connect the grains.
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arxiv:0810.2438
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macrospicules are relatively large spicule - like formations found mainly over the polar coronal holes when observing in the transition region spectral lines. in this study, we took advantage of the two short series of observations in the he ii 304 \ r { a } line obtained by the tesis solar observatory with a cadence of up to 3. 5 s to study the dynamics of macrospicules in unprecedented detail. we used a one - dimensional hydrodynamic method based on the assumption of their axial symmetry and on a simple radiative transfer model to reconstruct the evolution of the internal velocity field of 18 macrospicules from this dataset. besides the internal dynamics, we studied the motion of the apparent end points of the same 18 macrospicules and found 15 of them to follow parabolic trajectories with high precision which correspond closely to the obtained velocity fields. we found that in a clear, unperturbed case these macrospicules move with a constant deceleration inconsistent with a purely ballistic motion and have roughly the same velocity along their entire axis, with the obtained decelerations typically ranging from 160 to 230 m / s ^ 2, and initial velocities from 80 to 130 km / s. we also found a propagating acoustic wave for one of the macrospicules and a clear linear correlation between the initial velocities of the macrospicules and their decelerations, which indicates that they may be driven by magneto - acoustic shocks. finally, we inverted our previous method by taking velocities from the parabolic fits to give rough estimates of the percentage of mass lost by 12 of the macrospicules. we found that typically from 10 to 30 % of their observed mass fades out of the line ( presumably being heated to higher coronal temperatures ) with three exceptions of 50 % and one of 80 %.
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arxiv:1610.07536
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we develop off - shell formulations for $ { \ cal n } = 1 $ and $ { \ cal n } = 2 $ anti - de sitter supergravity theories in three spacetime dimensions that contain gauge two - forms in the auxiliary field sector. these formulations are shown to allow consistent couplings of supergravity to the green - schwarz superstring with $ { \ cal n } = 1 $ or $ { \ cal n } = 2 $ spacetime supersymmetry. in addition to being $ \ kappa $ - symmetric, the green - schwarz superstring actions constructed are also invariant under super - weyl transformations of the target space. we also present a detailed study of models for spontaneously broken local supersymmetry in three dimensions obtained by coupling the known off - shell $ { \ cal n } = 1 $ and $ { \ cal n } = 2 $ supergravity theories to nilpotent goldstino superfields.
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arxiv:1710.00554
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let g be the product of an abelian variety and a torus defined over a number field k. let r be a k - rational point on g of infinite order. call n _ r the number of connected components of the smallest algebraic k - subgroup of g to which r belongs. we prove that n _ r is the greatest positive integer which divides the order of ( r mod p ) for all but finitely many primes p of k. furthermore, let m > 0 be a multiple of n _ r and let s be a finite set of rational primes. then there exists a positive dirichlet density of primes p of k such that for every l in s the l - adic valuation of the order of ( r mod p ) equals v _ l ( m ).
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arxiv:0712.2812
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zebra finch are a model animal used in the study of audition. they are adept at recognizing zebra finch songs and the neural pathway involved in song recognition is well studied. here, this example is used to illustrate the estimation of mutual information between stimulus and response using a kozachenko - leonenko estimator. the challenge in calculating mutual information for spike trains is that there are no obvious coordinates for the data. the kozachenko - leonenko estimator does not require coordinates, it relies only on the distance between data points. in the case of bird song, estimating the mutual information demonstrates that the information content of spiking does not diminish as the song progresses.
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arxiv:2309.07618
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we give a full kinematical classification of all the tree - level two - pion photoproduction processes on the nucleon, which consists of seventeen diagrams. it suggests a method of analysis of two - pion data with little model bias.
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arxiv:nucl-th/0304072
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let $ k $ be a discretely valued field with ring of integers $ \ mathcal { o } _ k $ with perfect residue field. let $ k ( x ) $ be the rational function field in one variable. let $ \ mathbb { p } ^ 1 _ { \ mathcal { o } _ k } $ be the standard smooth model of $ \ mathbb { p } ^ 1 _ k $ with coordinate $ x $ on irreducible special fiber. let $ f ( x ) \ in \ mathcal { o } _ k [ x ] $ be a monic irreducible polynomial with corresponding divisor of zeroes $ \ text { div } _ 0 ( f ) $ on $ \ mathbb { p } ^ 1 _ { \ mathcal { o } _ k } $. we give an explicit description of the minimal embedded resolution $ \ mathcal { y } $ of the pair $ ( \ mathbb { p } ^ 1 _ { \ mathcal { o } _ k }, \ text { div } _ 0 ( f ) ) $ by using mac lane ' s theory to write down the discrete valuations on $ k ( x ) $ corresponding to the irreducible components of the special fiber of $ \ mathcal { y } $.
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arxiv:2105.03030
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many engineering systems require accurate simulations of complex physical systems. yet, analytical solutions are only available for simple problems, necessitating numerical approximations such as the finite element method ( fem ). the cost and accuracy of the fem scale with the resolution of the underlying computational mesh. to balance computational speed and accuracy meshes with adaptive resolution are used, allocating more resources to critical parts of the geometry. currently, practitioners often resort to hand - crafted meshes, which require extensive expert knowledge and are thus costly to obtain. our approach, adaptive meshing by expert reconstruction ( amber ), views mesh generation as an imitation learning problem. amber combines a graph neural network with an online data acquisition scheme to predict the projected sizing field of an expert mesh on a given intermediate mesh, creating a more accurate subsequent mesh. this iterative process ensures efficient and accurate imitation of expert mesh resolutions on arbitrary new geometries during inference. we experimentally validate amber on heuristic 2d meshes and 3d meshes provided by a human expert, closely matching the provided demonstrations and outperforming a single - step cnn baseline.
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arxiv:2406.14161
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hyperproperties express the relationship between multiple executions of a system. this is needed in many ai - related fields, such as knowledge representation and planning, to capture system properties related to knowledge, information flow, and privacy. in this paper, we study the monitoring of complex hyperproperties at runtime. previous work in this area has either focused on the simpler problem of monitoring trace properties ( which are sets of traces, while hyperproperties are sets of sets of traces ) or on monitoring first - order hyperproperties, which are expressible in temporal logics with first - order quantification over traces, such as hyperltl. we present the first monitoring algorithm for the much more expressive class of second - order hyperproperties. second - order hyperproperties include system properties like common knowledge, which cannot be expressed in first - order logics like hyperltl. we introduce hyper $ ^ 2 $ ltl $ _ f $, a temporal logic over finite traces that allows for second - order quantification over sets of traces. we study the monitoring problem in two fundamental execution models : ( 1 ) the parallel model, where a fixed number of traces is monitored in parallel, and ( 2 ) the sequential model, where an unbounded number of traces is observed sequentially, one trace after the other. for the parallel model, we show that the monitoring of the second - order hyperproperties of hyper $ ^ 2 $ ltl $ _ f $ can be reduced to monitoring first - order hyperproperties. for the sequential model, we present a monitoring algorithm that handles second - order quantification efficiently, exploiting optimizations based on the monotonicity of subformulas, graph - based storing of executions, and fixpoint hashing. we present experimental results from a range of benchmarks, including examples from common knowledge and planning.
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arxiv:2404.09652
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in this paper we outline general considerations on parameter identifiability, and introduce the notion of weak local identifiability and gradient weak local identifiability. these are based on local properties of the likelihood, in particular the rank of the hessian matrix. we relate these to the notions of parameter identifiability and redundancy previously introduced by rothenberg ( econometrica 39 ( 1971 ) 577 - 591 ) and catchpole and morgan ( biometrika 84 ( 1997 ) 187 - 196 ). within the exponential family parameter irredundancy, local identifiability, gradient weak local identifiability and weak local identifiability are shown to be equivalent. we consider applications to a recently developed class of cancer models of little and wright ( math biosciences 183 ( 2003 ) 111 - 134 ) and little et al. ( j theoret biol 254 ( 2008 ) 229 - 238 ) that generalize a large number of other recently used quasi - biological cancer models, in particular those of armitage and doll ( br j cancer 8 ( 1954 ) 1 - 12 ) and the two - mutation model ( moolgavkar and venzon math biosciences 47 ( 1979 ) 55 - 77 ).
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arxiv:0812.4701
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molecular generation, an essential method for identifying new drug structures, has been supported by advancements in machine learning and computational technology. however, challenges remain in multi - objective generation, model adaptability, and practical application in drug discovery. in this study, we developed a versatile ' plug - in ' molecular generation model that incorporates multiple objectives related to target affinity, drug - likeness, and synthesizability, facilitating its application in various drug development contexts. we improved the particle swarm optimization ( pso ) in the context of drug discoveries, and identified pso - enp as the optimal variant for multi - objective molecular generation and optimization through comparative experiments. the model also incorporates a novel target - ligand affinity predictor, enhancing the model ' s utility by supporting three - dimensional information and improving synthetic feasibility. case studies focused on generating and optimizing drug - like big marine natural products were performed, underscoring pso - enp ' s effectiveness and demonstrating its considerable potential for practical drug discovery applications.
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arxiv:2404.06691
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various other hypotheses. in that vein, theories are formulated according to most of the same scientific principles as hypotheses. scientists may generate a model, an attempt to describe or depict an observation in terms of a logical, physical or mathematical representation, and to generate new hypotheses that can be tested by experimentation. while performing experiments to test hypotheses, scientists may have a preference for one outcome over another. eliminating the bias can be achieved through transparency, careful experimental design, and a thorough peer review process of the experimental results and conclusions. after the results of an experiment are announced or published, it is normal practice for independent researchers to double - check how the research was performed, and to follow up by performing similar experiments to determine how dependable the results might be. taken in its entirety, the scientific method allows for highly creative problem solving while minimising the effects of subjective and confirmation bias. intersubjective verifiability, the ability to reach a consensus and reproduce results, is fundamental to the creation of all scientific knowledge. = = = scientific literature = = = scientific research is published in a range of literature. scientific journals communicate and document the results of research carried out in universities and various other research institutions, serving as an archival record of science. the first scientific journals, journal des scavans followed by philosophical transactions, began publication in 1665. since that time the total number of active periodicals has steadily increased. in 1981, one estimate for the number of scientific and technical journals in publication was 11, 500. most scientific journals cover a single scientific field and publish the research within that field ; the research is normally expressed in the form of a scientific paper. science has become so pervasive in modern societies that it is considered necessary to communicate the achievements, news, and ambitions of scientists to a wider population. = = = challenges = = = the replication crisis is an ongoing methodological crisis that affects parts of the social and life sciences. in subsequent investigations, the results of many scientific studies have been proven to be unrepeatable. the crisis has long - standing roots ; the phrase was coined in the early 2010s as part of a growing awareness of the problem. the replication crisis represents an important body of research in metascience, which aims to improve the quality of all scientific research while reducing waste. an area of study or speculation that masquerades as science in an attempt to claim legitimacy that it would not otherwise be able to achieve is sometimes referred to as pseudoscience,
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https://en.wikipedia.org/wiki/Science
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graph generative models often face a critical trade - off between learning complex distributions and achieving fast generation speed. we introduce autoregressive noisy filtration modeling ( anfm ), a novel approach that addresses both challenges. anfm leverages filtration, a concept from topological data analysis, to transform graphs into short sequences of monotonically increasing subgraphs. this formulation extends the sequence families used in previous autoregressive models. to learn from these sequences, we propose a novel autoregressive graph mixer model. our experiments suggest that exposure bias might represent a substantial hurdle in autoregressive graph generation and we introduce two mitigation strategies to address it : noise augmentation and a reinforcement learning approach. incorporating these techniques leads to substantial performance gains, making anfm competitive with state - of - the - art diffusion models across diverse synthetic and real - world datasets. notably, anfm produces remarkably short sequences, achieving a 100 - fold speedup in generation time compared to diffusion models. this work marks a significant step toward high - throughput graph generation.
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arxiv:2502.02415
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the dynamics of a generic class of scalar active matter exhibiting a diffusivity edge is studied in a confining potential where the amplitude is governed by a time - dependent protocol. for such non - equilibrium systems, the diffusion coefficient vanishes when the single - particle density field reaches a critical threshold, inducing a condensation transition that is formally akin to bose - einstein condensation. we show that this transition arises even for systems that do not reach a steady state, leading to condensation in finite time. since the transition can be induced for a fixed effective temperature by evolving the system, we effectively show that the temporal coordinate constitutes an alternative control parameter to tune the transition characteristics. for a constant - amplitude protocol, our generalised thermodynamics reduces in the steady - state limit to earlier results. lastly, we show numerically that for periodic modulation of the potential amplitude, the condensation transition is reentrant.
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arxiv:2312.09823
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particles bound to an interface interact because they deform its shape. the stresses that result are fully encoded in the geometry and described by a divergence - free surface stress tensor. this stress tensor can be used to express the force on a particle as a line integral along any conveniently chosen closed contour that surrounds the particle. the resulting expression is exact ( i. e., free of any " smallness " assumptions ) and independent of the chosen surface parametrization. additional surface degrees of freedom, such as vector fields describing lipid tilt, are readily included in this formalism. as an illustration, we derive the exact force for several important surface hamiltonians in various symmetric two - particle configurations in terms of the midplane geometry ; its sign is evident in certain interesting limits. specializing to the linear regime, where the shape can be analytically determined, these general expressions yield force - distance relations, several of which have originally been derived by using an energy based approach.
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arxiv:cond-mat/0506019
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using the effective - range expansion for the two - body amplitudes may generate spurious sub - threshold poles outside of the convergence range of the expansion. in the infinite volume, the emergence of such poles leads to the breakdown of unitarity in the three - body amplitude. we discuss the extension of our alternative subtraction scheme for including effective range corrections in pionless effective field theory for spinless bosons to nucleons. in particular, we consider the neutron - deuteron system in the doublet s - wave channel explicitly.
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arxiv:2308.09545
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satire detection and sentiment analysis are intensively explored natural language processing ( nlp ) tasks that study the identification of the satirical tone from texts and extracting sentiments in relationship with their targets. in languages with fewer research resources, an alternative is to produce artificial examples based on character - level adversarial processes to overcome dataset size limitations. such samples are proven to act as a regularization method, thus improving the robustness of models. in this work, we improve the well - known nlp models ( i. e., convolutional neural networks, long short - term memory ( lstm ), bidirectional lstm, gated recurrent units ( grus ), and bidirectional grus ) with adversarial training and capsule networks. the fine - tuned models are used for satire detection and sentiment analysis tasks in the romanian language. the proposed framework outperforms the existing methods for the two tasks, achieving up to 99. 08 % accuracy, thus confirming the improvements added by the capsule layers and the adversarial training in nlp approaches.
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arxiv:2306.07845
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surface solar irradiance ( ssi ) plays a crucial role in tackling climate change - as an abundant, non - fossil energy source, exploited primarily via photovoltaic ( pv ) energy production. with the growing contribution of ssi to total energy production, the stability of the latter is challenged by the intermittent character of the former, arising primarily from cloud effects. mitigating this stability challenge requires accurate, uncertainty - aware, near real - time, regional - scale ssi forecasts with lead times of minutes to a few hours, enabling robust real - time energy grid management. state - of - the - art nowcasting methods typically meet only some of these requirements. here we present shadecast, a deep generative diffusion model for the probabilistic spatiotemporal nowcasting of ssi, conditioned on deterministic aspects of cloud evolution to guide the probabilistic ensemble forecast, and based on near real - time satellite data. we demonstrate that shadecast provides improved forecast quality, reliability, and accuracy in different weather scenarios. our model produces realistic and spatiotemporally consistent predictions outperforming the state of the art by 15 % in the continuous ranked probability score ( crps ) over different regions up to 512 km x 512 km with lead times of 15 - 120 min. conditioning the ensemble generation on deterministic forecasts improves reliability and performance by more than 7 % on crps. our approach empowers grid operators and energy traders to make informed decisions, ensuring stability and facilitating the seamless integration of pv energy across multiple locations simultaneously.
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arxiv:2312.11966
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the arecibo legacy fast alfa ( alfalfa ) survey is an on - going second generation blind extragalactic hi survey exploiting arecibo ' s superior sensitivity, angular resolution and digital technology to conduct a census of the local hi universe over a cosmologically significant volume. as of mid - 2007, ~ 4500 good quality extragalactic hi line sources have been extracted in ~ 15 % of the final survey area. alfalfa is detecting hi masses as low as 10 * * 6 msun and as high as 10 * * 10. 8 msun with positional accuracies typically better than 20 arcsec, allowing immediate identification of the most probable optical counterparts. only 3 % of all extragalactic hi sources and fewer than 1 % of detections with m ( hi ) > 10 * * 9. 5 msun cannot be identified with a stellar component. first alfalfa results already suggest, in agreement with previous studies, that there does not appear to be a cosmologically significant population of optically dark but hi rich galaxies. alfalfa promises a wealthy dataset for the exploration of many issues in near - field cosmology and galaxy evolution studies, setting the stage for their extension to higher redshifts with the square kilometer array ( ska ).
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arxiv:0708.2547
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for every $ g \ in \ mathbb { n } _ 0 $ and $ \ epsilon > 0 $, we construct a smooth genus $ g $ surface embedded into the unit ball with area $ 8 \ pi $ and willmore energy smaller than $ 8 \ pi + \ epsilon $. from this we deduce that a minimising sequence for willmore ' s energy in the class of genus $ g $ surfaces embedded in the unit ball with area $ 8 \ pi $ converges to a doubly covered sphere for all $ g \ in \ mathbb { n } _ 0 $. we obtain the same result for certain canham - helfrich energies with $ \ chi _ k \ leq 0 $ without genus constraint and show that canham - helfrich energies with $ \ chi _ k > 0 $ are not bounded from below in the class of smooth surfaces with area $ s $ embedded into a domain $ \ omega \ subset \ mathbb { r } ^ 3 $. furthermore, we prove that the class of connected surfaces embedded in a domain $ \ omega \ subset \ mathbb { r } ^ 3 $ with uniformly bounded willmore energy and area is compact under varifold convergence.
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arxiv:1608.02823
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in this paper, we investigate vortex dynamics in a two - dimensional bose - hubbard model coupled with a weak artificial magnetic field, a random white noise and a dissipation. origin of the noise and dissipation is considered as thermal fluctuations of atoms that do not participate the bose - einstein condensation ( bec ). solving a stochastic gross - pitaevskii equation to this system, we show that the interplay of the magnetic field and the white noise generates vortices in the bulk of the bec and stable steady states of vortices form after a transition period. we calculate the incompressible part of the kinetic - energy spectrum of the bec. in the transition period, a kolmogorov $ k ^ { - 5 / 3 } $ spectrum appears in the infrared regime with the wave number $ k $, $ k < \ zeta ^ { - 1 } $, where $ \ zeta $ is the healing length, whereas in the ultraviolet region, $ k > \ zeta ^ { - 1 } $, the spectrum behaves as $ k ^ { - 3 } $. on the other hand in the steady states, another scaling low appears. we find a relationship between the above mentioned kinetic - energy spectra and the velocity of vortices. by an inverse cascade, the large velocity of a few created vortices develops the kolmogorov $ k ^ { - 5 / 3 } $ spectrum.
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arxiv:1703.02750
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in an experiment on three - photon laser excitation $ 5s _ { 1 / 2 } \ to 5p _ { 3 / 2 } \ to 6s _ { 1 / 2 } \ to 37p _ { 3 / 2 } $ of a single $ ^ { 87 } $ rb rydberg atom in an optical dipole trap, we have observed for the first time three - photon rabi oscillations between the ground and the rydberg states. the single atom was detected optically by measuring the signal of resonant fluorescence with a low - noise scmos video camera. relative probability of the atom to remain in the trap after the action of three synchronized laser excitation pulses was measured for their durations varied in the range from 100 ns to 2 $ \ mu $ s. a specific feature of the experiment was the usage of intense laser radiation at the wavelength of 1367 nm on the second excitation step, which provided the single - photon rabi frequency up to 2 ghz to control the effective detunings of the intermediate levels of the three - photon transition due to ac stark effect. we have detected rabi oscillations with frequency from 1 to 5 mhz depending on the intensities of the laser pulses on the first and the second excitation steps with the coherence time of 0. 7 - 0. 8 $ \ mu $ s. the ways to increase the coherence time and contrast of the three - photon rabi oscillations for applications in quantum information processing with rydberg atoms are discussed.
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arxiv:2410.01703
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we study the final - state interactions in $ b \ to \ pi k $ decays through $ b \ to vv \ to \ pi k $ processes where the inelastic rescattering occurs via single pion exchange. the next - to - leading order low energy effective hamiltonian and bsw model are used to evaluate the weak transition matrix elements and the final - state interactions. we found that the final - state interaction effects in $ b \ to \ rho k ^ * \ to \ pi k $ processes are significant. the fleischer - mannel relation about the ckm angle $ \ gamma $ may be significantly modified.
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arxiv:hep-ph/9805260
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the european far - infrared ( fir ) space roadmap focuses on fundamental, yet still unresolved, astrophysical questions that can only be answered through a far - infrared space mission and gives an overview of the technology required to answer them. the document discusses topics ranging from solar system and planet formation, our galaxy and nearby galaxies and distant galaxies and galaxy evolution. the fir roadmap was open to comments from the wider astronomical community following a presentation during ewass 2016.
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arxiv:1701.00366
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we prove that inflation is forbidden in the most well understood class of semi - realistic type iia string compactifications : calabi - yau compactifications with only standard ns - ns 3 - form flux, r - r fluxes, d6 - branes and o6 - planes at large volume and small string coupling. with these ingredients, the first slow - roll parameter satisfies epsilon > = 27 / 13 whenever v > 0, ruling out both inflation ( including brane / anti - brane inflation ) and de sitter vacua in this limit. our proof is based on the dependence of the 4 - dimensional potential on the volume and dilaton moduli in the presence of fluxes and branes. we also describe broader classes of iia models which may include cosmologies with inflation and / or de sitter vacua. the inclusion of extra ingredients, such as ns 5 - branes and geometric or non - geometric ns - ns fluxes, evades the assumptions used in deriving the no - go theorem. we focus on ns 5 - branes and outline how such ingredients may prove fruitful for cosmology, but we do not provide an explicit model. we contrast the results of our iia analysis with the rather different situation in iib.
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arxiv:0711.2512
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the paper addresses a problem of sequential bilateral bargaining with incomplete information. we proposed a decision model that helps agents to successfully bargain by performing indirect negotiation and learning the opponent ' s model. methodologically the paper casts heuristically - motivated bargaining of a self - interested independent player into a framework of bayesian learning and markov decision processes. the special form of the reward implicitly motivates the players to negotiate indirectly, via closed - loop interaction. we illustrate the approach by applying our model to the nash demand game, which is an abstract model of bargaining. the results indicate that the established negotiation : i ) leads to coordinating players ' actions ; ii ) results in maximising success rate of the game and iii ) brings more individual profit to the players.
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arxiv:2409.06566
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many complex networks exhibit vulnerability to spreading of epidemics, and such vulnerability relates to the viral strain as well as to the network characteristics. for instance, the structure of the network plays an important role in spreading of epidemics. additionally, properties of previous epidemic models require prior knowledge of the complex network structure, which means the models are limited to only well - known network structures. in this paper, we propose a new epidemiological sir model based on the continuous time markov chain, which is generalized to any type of network. the new model is capable of evaluating the states of every individual in the network. through mathematical analysis, we prove an epidemic threshold exists below which an epidemic does not propagate in the network. we also show that the new epidemic threshold is inversely proportional to the spectral radius of the network. in particular, we employ the new epidemic model as a novel measure to assess the vulnerability of networks to the spread of epidemics. the new measure considers all possible effective infection rates that an epidemic might possess. next, we apply the measure to correlated networks to evaluate the vulnerability of disassortative and assortative scalefree networks. ultimately, we verify the accuracy of the theoretical epidemic threshold through extensive numerical simulations. within the set of tested networks, the numerical results show that disassortative scale - free networks are more vulnerable to spreading of epidemics than assortative scale - free networks.
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arxiv:1004.1663
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in many sciences one often builds large systems out of smaller constituent parts. mathematically, to study these systems, one can attach data to the component pieces via a functor f. this is of great practical use if f admits a compositional structure which is compatible with that of the system under study ( i. e. if the local data defined on the pieces can be combined into global data ). however, sometimes this does not occur. thus one can ask : ( 1 ) does f fail to be compositional? ( 2 ) if so, can this failure be quantified? and ( 3 ) are there general tools to fix failures of compositionality? the kind of compositionality we study in this paper is one in which one never fails to combine local data into global data. this is formalized via the understudied notion of what we call a lavish presheaf : one that satisfies the existence requirement of the sheaf condition, but not uniqueness. adapting \ v { c } ech cohomology to presheaves, we show that a presheaf has trivial zeroth presheaf - \ v { c } ech cohomology if and only if it is lavish. in this light, cohomology is a measure of the failure of compositionality. the key contribution of this paper is to show that, in some instances, cohomology can itself display compositional structure. formally, we show that, given any abelian presheaf f : c ^ op - - > a and any grothendieck pretopology j, if f is flasque and separated, then the zeroth cohomology functor h ^ 0 ( -, f ) : c ^ op - - > a is lavish. this follows from observation that, for separated presheaves, h ^ 0 ( -, f ) can be written as a cokernel of the unit of the adjunction given by sheafification. this last fact is of independent interest since it shows that cohomology is a measure of ` ` distance ' ' between separated presheaves and their closest sheaves ( their sheafifications ). on the other hand, the fact that h ^ 0 ( -, f ) is a lavish presheaf has unexpected algorithmic consequences.
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arxiv:2407.03488
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we present dynamical modeling of the broad - line region ( blr ) for the highly variable agn sdss j141041. 25 + 531849. 0 ( $ z = 0. 359 $ ) using photometric and spectroscopic monitoring data from the sloan digital sky survey reverberation mapping project and the sdss - v black hole mapper program, spanning from early 2013 to early 2023. we model the geometry and kinematics of the blr in the h $ \ beta $, h $ \ alpha $, and mgii, emission lines for three different time periods to measure the potential change of structure within the blr across time and line species. we consistently find a moderately edge - on $ ( i _ { \ rm full - state } = 53. 29 ^ { \ circ } \, { } ^ { + 7. 29 } _ { - 6. 55 } ) $ thick - disk $ ( \ theta _ { \ rm opn, \ ; full - state } = 54. 86 ^ { \ circ } \, { } ^ { + 5. 83 } _ { - 4. 74 } ) $ geometry for all blrs, with a joint estimate for the mass of the supermassive black hole ( smbh ) for each of three time periods, yielding $ \ log _ { 10 } ( m _ { \ rm bh } / m _ { \ odot } ) = 7. 66 ^ { + 0. 12 } _ { - 0. 13 } $ when using the full dataset. the inferred individual virial factor $ f $ $ \ sim 1 $ is significantly smaller than the average factor for a local sample of dynamically modeled agns. there is strong evidence for non - virial motion, with over $ 80 \ % $ of clouds on inflowing / outflowing orbits. we analyze the change in model parameters across emission lines, finding the radii of blrs for the emission lines are consistent with the following relative sizes $ r _ { \ rm h \ beta } \ lesssim r _ { \ rm mgii } \ lesssim r _ { \ rm h \ alpha } $. comparing results across time, we find $ r _ { \ rm low - state } \ lesssim r _ { \ rm high - state } $, with the change in blr size for h $ \ beta $, being more significant than for the other two lines.
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arxiv:2408.04789
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with the global population expected to reach 9. 7 billion by 2050, there is an urgent need for alternative protein sources that are sustainable, nutritious, and environmentally friendly. plant - based proteins are gaining popularity as they require fewer resources and produce fewer greenhouse gas emissions compared to animal - based proteins. companies like beyond meat and impossible foods have developed plant - based meat alternatives that mimic the taste and texture of traditional meat products. = = = food waste reduction = = = approximately one - third of all food produced globally is wasted. innovative food tech solutions are being developed to address this issue. for example, apeel sciences has developed an edible coating that extends the shelf life of fruits and vegetables, reducing spoilage and waste. = = consumer acceptance = = historically, consumers paid little attention to food technologies. nowadays, the food production chain is long and complicated and food technologies are diverse. consequently, consumers are uncertain about the determinants of food quality and find it difficult to understand them. now, acceptance of food products very often depends on perceived benefits and risks associated with food. popular views of food processing technologies matter. especially innovative food processing technologies often are perceived as risky by consumers. acceptance of the different food technologies varies. while pasteurization is well recognized and accepted, high pressure treatment and even microwaves often are perceived as risky. studies by the hightech europe project found that traditional technologies were well accepted in contrast to innovative technologies. consumers form their attitude towards innovative food technologies through three main mechanisms : first, through knowledge or beliefs about risks and benefits correlated with the technology ; second, through attitudes based on their own experience ; and third, through application of higher order values and beliefs. a number of scholars consider the risk - benefit trade - off as one of the main determinants of consumer acceptance, although some researchers place more emphasis on the role of benefit perception ( rather than risk ) in consumer acceptance. rogers ( 2010 ) defines five major criteria that explain differences in the acceptance of new technology by consumers : complexity, compatibility, relative advantage, trialability and observability. acceptance of innovative technologies can be improved by providing non - emotional and concise information about these new technological processes methods. the hightech project also suggests that written information has a higher impact on consumers than audio - visual information. = = publications = = food and bioprocess technology food technology lwt - food science and technology = = see also = = agricultural technology food biotechnology food packaging food grading molecular gastronomy optical sorting standard components ( food processing ) list of
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https://en.wikipedia.org/wiki/Food_technology
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for a finite - dimensional algebra $ \ lambda $ over an algebraically closed field $ k $, it is known that the poset of $ 2 $ - term silting objects in $ \ mathrm { k } ^ b ( \ operatorname { proj } \ lambda ) $ is isomorphic to the poset of functorially finite torsion classes in $ \ operatorname { mod } \ lambda $, and to that of complete cotorsion classes in $ \ mathrm { k } ^ { [ - 1, 0 ] } ( \ operatorname { proj } \ lambda ) $. in this work, we generalise this result to the case of $ d $ - term silting objects for arbitrary $ d \ geq 2 $ by introducing the notion of torsion classes for extriangulated categories. in particular, we show that the poset of $ d $ - term silting objects in $ \ mathrm { k } ^ b ( \ operatorname { proj } \ lambda ) $ is isomorphic to the poset of complete and hereditary cotorsion classes in $ \ mathrm { k } ^ { [ - d + 1, 0 ] } ( \ operatorname { proj } \ lambda ) $, and to that of positive and functorially finite torsion classes in $ d ^ { [ - d + 2, 0 ] } ( \ operatorname { mod } \ lambda ) $, an extension - closed subcategory of $ d ^ b ( \ operatorname { mod } \ lambda ) $. we further show that the posets $ \ operatorname { cotors } \ mathrm { k } ^ { [ - d + 1, 0 ] } ( \ operatorname { proj } \ lambda ) $ and $ \ operatorname { tors } d ^ { [ - d + 2, 0 ] } ( \ operatorname { mod } \ lambda ) $ are lattices, and that the truncation functor $ \ tau _ { \ geq - d + 2 } $ gives an isomorphism between the two.
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arxiv:2407.10562
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in many shell model interactions, the tensor force monopole matrix elements often retain systematic trends originating in the bare tensor force. however, in the present work, we find that isospin t = 0 tensor force monopole matrix elements of \ textit { p } - shell effective interaction ck ( 8 - 16 ) do not share these systematic. we correct these discrepancies by modifying t = 0 tensor force two - body matrix elements ( tbmes ) of ck ( 8 - 16 ) by the analytically calculated tensor force tbmes. with some additional modification of single - particle energies and tbmes, the revised effective interaction is named as ckn. the effective interaction ckn has been tested for the calculations of \ textit { p } - shell nuclei of normal parity states from various physics viewpoints such as excitation spectra, electromagnetic moments, and electromagnetic and \ textit { g } amow - \ textit { t } eller ( \ textit { gt } ) transitions. the obtained results are found to be satisfactory.
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arxiv:2006.00889
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since smart cities aim at becoming self - monitoring and self - response systems, their deployment relies on close resource monitoring through large - scale urban sensing. the subsequent gathering of massive amounts of data makes essential the development of event - filtering mechanisms that enable the selection of what is relevant and trustworthy. due to the rise of mobile event producers, location information has become a valuable filtering criterion, as it not only offers extra information on the described event, but also enhances trust in the producer. implementing mechanisms that validate the quality of location information becomes then imperative. the lack of such strategies in cloud architectures compels the adoption of new communication schemes for internet of things ( iot ) - based urban services. to serve the demand for location verification in urban event - based systems ( debs ), we have designed three different fog architectures that combine proximity and cloud communication. we have used network simulations with realistic urban traces to prove that the three of them can correctly identify between 73 % and 100 % of false location claims.
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arxiv:2312.09921
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a halo is an intrinsically quantum object defined as a bound state of a spatial size which extends deeply into the classically forbidden region. previously, halos have been observed in bound states of two and less frequently of three atoms. here, we propose a realization of halo states containing as many as six atoms. we report the binding energies, pair correlation functions, spatial distributions, and sizes of few - body clusters composed by bosonic dipolar atoms in a bilayer geometry. we find two very distinct halo structures, for large interlayer separation the halo structure is roughly symmetric and we discover an unusual highly anisotropic shape of halo states close to the unbinding threshold. our results open avenues of using ultracold gases for the experimental realization of halos with the largest number of atoms ever predicted before.
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arxiv:2101.05969
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the advent of alphago and its successors marked the beginning of a new paradigm in playing games using artificial intelligence. this was achieved by combining monte carlo tree search, a planning procedure, and deep learning. while the impact on the domain of games has been undeniable, it is less clear how useful similar approaches are in applications beyond games and how they need to be adapted from the original methodology. we review 129 peer - reviewed articles detailing the application of neural monte carlo tree search methods in domains other than games. our goal is to systematically assess how such methods are structured in practice and if their success can be extended to other domains. we find applications in a variety of domains, many distinct ways of guiding the tree search using learned policy and value functions, and various training methods. our review maps the current landscape of algorithms in the family of neural monte carlo tree search as they are applied to practical problems, which is a first step towards a more principled way of designing such algorithms for specific problems and their requirements.
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arxiv:2303.08060
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we combine vision transformers with operator learning to solve diverse inverse problems described by partial differential equations ( pdes ). our approach, named vito, combines a u - net based architecture with a vision transformer. we apply vito to solve inverse pde problems of increasing complexity, namely for the wave equation, the navier - stokes equations and the darcy equation. we focus on the more challenging case of super - resolution, where the input dataset for the inverse problem is at a significantly coarser resolution than the output. the results we obtain are comparable or exceed the leading operator network benchmarks in terms of accuracy. furthermore, vito ` s architecture has a small number of trainable parameters ( less than 10 % of the leading competitor ), resulting in a performance speed - up of over 5x when averaged over the various test cases.
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arxiv:2303.08891
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we present the analysis of an unusual failed eruption captured in high cadence and in many wavelengths during the observing campaign in support of the vault2. 0 sounding rocket launch. the refurbished very high angular resolution ultraviolet telescope ( vault2. 0 ) is a ly $ \ alpha $ ( $ \ lambda $ 1216 { \ aa } ) spectroheliograph launched on september 30, 2014. the campaign targeted active region noaa ar 12172 and was closely coordinated with the hinode and iris missions and several ground - based observatories ( nso / ibis, solis, and bbso ). a filament eruption accompanied by a low level flaring event ( at the goes c - class level ) occurred around the vault2. 0 launch. no coronal mass ejection ( cme ) was observed. the eruption and its source region, however, were recorded by the campaign instruments in many atmospheric heights ranging from the photosphere to the corona in high cadence and spatial resolution. this is a rare occasion which enables us to perform a comprehensive investigation on a failed eruption. we find that a rising magnetic flux rope - like ( mfr ) structure was destroyed during its interaction with the ambient magnetic field creating downflows of cool plasma and diffuse hot coronal structures reminiscent of " cusps ". we employ magnetofrictional simulations to show that the magnetic topology of the ambient field is responsible for the destruction of the mfr. our unique observations suggest that the magnetic topology of the corona is a key ingredient for a successful eruption.
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arxiv:1706.00057
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