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we study a model of an infinite system of point particles in $ \ mathds { r } ^ d $ performing random jumps with attraction. the system ' s states are probability measures on the space of particle configurations, and their evolution is described by means of kolmogorov and fokker - planck equations. instead of solving these equations directly we deal with correlation functions evolving according to a hierarchical chain of differential equations, derived from the kolmogorov equation. under quite natural conditions imposed on the jump kernels - - and analyzed in the paper - - we prove that this chain has a unique classical sub - poissonian solution on a bounded time interval. this gives a partial answer to the question whether the sub - poissonicity is consistent with any kind of attraction. we also discuss possibilities to get a complete answer to this question.
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arxiv:1612.08198
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classical novae are stellar explosions occurring in binary systems, consisting of a white dwarf and a main sequence companion. thermonuclear runaways on the surface of massive white dwarfs, consisting of oxygen and neon, are believed to reach peak temperatures of several hundred million kelvin. these temperatures are strongly correlated with the underlying white dwarf mass. the observational counterparts of such models are likely associated with outbursts that show strong spectral lines of neon in their shells ( neon novae ). the goals of this work are to investigate how useful elemental abundances are for constraining the peak temperatures achieved during these outbursts and determine how robust " nova thermometers " are with respect to uncertain nuclear physics input. we present updated observed abundances in neon novae and perform a series of hydrodynamic simulations for several white dwarf masses. we find that the most useful thermometers, n / o, n / al, o / s, s / al, o / na, na / al, o / p, and p / al, are those with the steepest monotonic dependence on peak temperature. the sensitivity of these thermometers to thermonuclear reaction rate variations is explored using post - processing nucleosynthesis simulations. the ratios n / o, n / al, o / na, and na / al are robust, meaning they are minimally affected by uncertain rates. however, their dependence on peak temperature is relatively weak. the ratios o / s, s / al, o / p, and p / al reveal strong dependences on temperature and the poorly known 30p ( p, g ) 31s rate. we compare our model predictions to neon nova observations and obtain the following estimates for the underlying white dwarf masses : 1. 34 - 1. 35 solar masses ( v838 her ), 1. 18 - 1. 21 solar masses ( v382 vel ), < 1. 3 solar masses ( v693 cra ), < 1. 2 solar masses ( lmc 1990 # 1 ), and < 1. 2 solar masses ( qu vul ).
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arxiv:1211.4794
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we study $ u ( n ) $ chern - simons theory coupled to massive fundamental fermions in the lightcone hamiltonian formalism. focusing on the planar limit, we introduce a consistent regularization scheme, identify the counter terms needed to restore relativistic invariance, and formulate scattering theory in terms of unambiguously defined asymptotic states. we determine the $ 2 \ to 2 $ planar s - matrix element in the singlet channel by solving the lippmann - schwinger equation to all orders, establishing a result previously conjectured in the literature
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arxiv:2205.09144
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on a pair of episodes of the bones television series space dandy ( 2014 ) ; and both received critical acclaim. additional subcontracting work included opening credits animation for several of the animated garo series ( 2014 - 15 ; 2017 - 18 ) ; animation assistance for yo - kai watch : the movie ( 2014 ), a pair of crayon shin - chan films ( 2014, 2015 ), and typhoon noruda ( 2015 ) ; and animation production for the promotional mini - series what ' s debikuro? ( 2014 ), the music video song of four seasons ( 2015 ), and promotional episodes for the american animated series ok k. o.! : let ' s be heroes ( 2015 - 17 ). = = = move to feature films ( 2016 – 2017 ) = = = by early 2016, science saru had gained experience and built a name in the industry ; while still a small team, the company was ready to undertake its first large - scale project. the studio ' s first feature film production, the family - friendly fantasy film lu over the wall ( 2017 ), was produced in less than 16 months using ' digitally assisted ' animation techniques. yuasa directed and co - wrote lu over the wall ; it was his first feature film with an original story. during the production of lu over the wall, yuasa and science saru were offered the opportunity to produce a second feature film, the comedy romance night is short, walk on girl ( 2017 ), based on the novel by tomihiko morimi. prior to the establishment of science saru, yuasa had directed a television series adaptation of morimi ' s novel the tatami galaxy ( 2010 ) ; yuasa had originally hoped to adapt night is short, walk on girl immediately after that production, but was unable to at the time. when he was offered the opportunity in 2016, he immediately agreed. this resulted in the pre - production work on night is short, walk on girl overlapping with the post - production of lu over the wall. although lu over the wall was completed first, it was released after night is short, walk on girl ; this was in part due to a marketing suggestion that it might be preferable for the studio ' s first film to be based on a pre - existing property familiar to japanese audiences. both lu over the wall and night is short, walk on girl received immediate critical acclaim. lu over the wall received the annecy cristal du long metrage, the mainichi film awards ' ofuji noburo
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https://en.wikipedia.org/wiki/Science_Saru
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we study the penrose limit about a null geodesic with 3 equal angular momenta in the recently obtained type iib solution dual to an exactly marginal $ \ gamma $ - deformation of n = 4 sym. the resulting background has non - trivial ns 3 - form flux as well as rr 5 - and 3 - form fluxes. we quantise the light - cone green - schwarz action and show that it exhibits a continuum spectrum. we show that this is related to the dynamics of a charged particle moving in a landau plane with an extra interaction induced by the deformation. we interpret the results in the dual n = 1 scft.
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arxiv:hep-th/0505243
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graph neural networks have become a powerful framework for learning complex structure - property relationships and fast screening of chemical compounds. recently proposed methods have demonstrated that using 3d geometry information of the molecule along with the bonding structure can lead to more accurate prediction on a wide range of properties. a common practice is to use 3d geometries computed through density functional theory ( dft ) for both training and testing of models. however, the computational time needed for dft calculations can be prohibitively large. moreover, many of the properties that we aim to predict can often be obtained with little or no overhead on top of the dft calculations used to produce the 3d geometry information, voiding the need for a predictive model. to be practically useful for high - throughput chemical screening and drug discovery, it is desirable to work with 3d geometries obtained using less - accurate but much more efficient non - dft methods. in this work we investigate the impact of using non - dft conformations in the training and the testing of existing models and propose a data augmentation method for improving the prediction accuracy of classical forcefield - derived geometries.
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arxiv:2203.04697
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we report the discovery of a large ( $ \ sim 10 $ kpc diameter ), massive ( $ \ log ( m _ \ star / m _ \ odot ) = 10. 15 ^ { + 0. 01 } _ { - 0. 01 } $ ), grand - design spiral galaxy with photometric redshift $ z _ { \ text { phot } } = 4. 03 $ in the uncover and medium band mega science surveys with jwst. this is the highest redshift spiral galaxy discovered with jwst so far. in the rest - frame near - uv and far - uv, we clearly see the beads - on - a - string pattern of star formation ; in the rest - frame visible bands, each string appears as an arm. spectral energy distribution modeling using the bagpipes code is strongly constrained by detections and flux measurements in 21 jwst and hst filters. the stellar mass - weighted age is 228 myr, implying that 50 % of the stars in the galaxy formed after $ z \ sim 4. 5 $. this is a highly star - forming galaxy with a star formation rate ( sfr ) of $ 57. 57 ^ { + 1. 80 } _ { - 1. 90 } \, m _ \ odot \, \ text { yr } ^ { - 1 } $. we detect strong h - $ \ alpha $ + [ nii ] emission from the entire disk. the detection of a spiral galaxy at $ z \ sim 4 $ indicates that massive and large spiral galaxies and disks were already in place merely 1. 5 billion years after the big bang.
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arxiv:2412.04834
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we present detailed analysis of high - resolution c18o ( 2 - 1 ), so ( 88 - 77 ), co ( 3 - 2 ) and dco + ( 3 - 2 ) data obtained by the atacama large millimeter / sub - millimeter array ( alma ) towards a class 0 keplerian circumbinary disk around vla1623a, which represents one of the most complete analysis towards a class 0 source. from the dendrogram analysis, we identified several accretion flows feeding the circumbinary disk in a highly anisotropic manner. stream - like so emission around the circumbinary disk reveals the complicated shocks caused by the interactions between the disk, accretion flows and outflows. a wall - like structure is discovered south of vla1623b. the discovery of two outflow cavity walls at the same position traveling at different velocities suggests the two outflows from both vla1623a and vla1623b overlays on top of each other in the plane of sky. our detailed flat and flared disk modeling shows that cycle 2 c18o j = 2 - 1 data is inconsistent with the combined binary mass of 0. 2 msun as suggested by early cycle 0 studies. the combined binary mass for vla1623a should be modified to 0. 3 ~ 0. 5 msun.
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arxiv:1904.00133
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we propose a frequency domain method based on robust independent component analysis ( rica ) to address the multichannel blind source separation ( bss ) problem of convolutive speech mixtures in highly reverberant environments. we impose regularization processes to tackle the ill - conditioning problem of the covariance matrix and to mitigate the performance degradation in the frequency domain. we apply an algorithm to separate the source signals in adverse conditions, i. e. high reverberation conditions when short observation signals are available. furthermore, we study the impact of several parameters on the performance of separation, e. g. overlapping ratio and window type of the frequency domain method. we also compare different techniques to solve the frequency - domain permutation ambiguity. through simulations and real world experiments, we verify the superiority of the presented convolutive algorithm among other bss algorithms, including recursive regularized ica ( rr ica ), independent vector analysis ( iva ).
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arxiv:1408.0193
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the undecidability of the additive theory of primes ( with identity ) as well as the theory th ( n, +, n - > p \ _ n ), where p \ _ n denotes the ( n + 1 ) - th prime, are open questions. as a possible approach, we extend the latter theory by adding some extra function. in this direction we show the undecidability of the existential part of the theory th ( n, +, n - > p \ _ n, n - > r \ _ n ), where r \ _ n is the remainder of p \ _ n divided by n in the euclidian division.
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arxiv:math/0609554
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in vertebrates, olfactory sensory neurons choose only one olfactory receptor to produce out of ~ 2000 possibilities. the mechanism for how this singular receptor expression occurs is unknown. here we propose a mechanism that can stochastically select a single gene out of a large number of possibilities. in this model, receptor genes compete for a limited pool of transcription factors ( tfs ). the gene that recruits a target number of tfs is selected for expression. to support this mechanism, we have attempted to detect repeated motifs within known sequences of mouse olfactory receptor promoters. we find motifs that are significantly overrepresented in olfactory versus other gene promoters. we identify possible tfs that can target these motifs. our model suggests that a small number of tfs can control the selection of a single gene out of ~ 2000 possibilities.
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arxiv:1201.2933
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the " genetic purity " of french wild boar populations has been monitored since the 1980s based on a cytogenetic difference between wild boars and domestic pigs ( 36 and 38 chromosomes, respectively ). this difference makes it possible to identify any boar with 37 or 38 chromosomes as " hybrid ", without however being able to determine the origin ( recent or ancient ) of the hybridization, nor guarantee the " purity " of an animal with 36 chromosomes. analysis of results of more than 4, 600 tests performed over the last 12 years reveals an average " hybrid " rate of 15. 8 %, with high variability between populations. to analyse hybridization in greater detail and overcome inherent limitations of the cytogenetic approach, 362 wild boars recently collected in different regions of france were genotyped on a 70k snp ( geneseek ggp porcine hd ) chip. this study showed that for 96. 4 % of the wild boars analysed, includingmost of those with 37 or 38 chromosomes, the percentage of the genome of " domestic pig " origin varied from 0 to 18 %. this suggests that hybridization is a fairly common phenomenon but of moderate intensity, and often ancient. nevertheless, higher rates of hybridization have been observed in some regions such as ard { \ ` e } che, and several cases of recent hybridization with domestic pigs were found in 3. 6 % of the wild boars analysed, most of them with pigs of asian origin.
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arxiv:2112.08876
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a codec for compression of music signals is proposed. the method belongs to the class of transform lossy compression. it is conceived to be applied in the high quality recovery range though. the transformation, endowing the codec with its distinctive feature, relies on the ability to construct high quality sparse approximation of music signals. this is achieved by a redundant trigonometric dictionary and a dedicated pursuit strategy. the potential of the approach is illustrated by comparison with the ogg vorbis format, on a sample consisting of clips of melodic music. the comparison evidences remarkable improvements in compression performance for the identical quality of the decompressed signal.
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arxiv:1512.04243
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studies of the doping process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. in this work, we studied the doping effects on the crystal structure, electric, morphologic and magnetic properties of the bscco system with the nominal composition $ bi _ { 1. 6 } pb _ { 0. 4 } sr _ { ( 2 - x ) } re _ xca _ 2cu _ 3o _ { ( 10 - { \ delta } ) } $. here, the rare earth element ( re ) was replaced by la in the sites of sr. the x was ranged from 0. 0 to 2. 0, in steps of 0. 5. the samples were prepared based on pechini ' s method. the resulting powder was pressed at room temperature and the pellets were submitted to several heat treatments. the characterizations confirm the la in the sites of sr however, the superconducting properties of the sample were not improved.
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arxiv:1311.7353
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enveloped viral infections require fusion with cellular membranes for viral genome entry, occurring only following interaction of viral and cellular membranes allowing fusion pore formation, by which the virus accesses the cytoplasm. here, we focus on interferon - induced transmembrane protein 3 ( ifitm3 ) and its antiviral activity. ifitm3 is predicted to block or stall viral fusion at an intermediate state, causing viral propagation to fail. after introducing ifitm3, we describe the generalized lipid membrane fusion pathway and how it can be stalled, particularly with respect to ifitm3, and current questions regarding ifitm3 ' s topology. specific emphasis is placed on ifitm3 ' s amphipathic a - helix ( aah ) 59v - 68m, necessary for antiviral activity. calculations are reported of hydrophobicity and hydrophobic moment of this peptide and active site peptides from other membrane - remodeling proteins. finally, we discuss the effects of post - translational modifications and localization, how ifitm3 ' s aah may block viral fusion, and possible ramifications of membrane composition.
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arxiv:2204.03054
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let $ f \ in \ ell ^ 2 ( \ mathbb z ) $. define the average of $ f $ over the square integers by $ a _ n f ( x ) : = \ frac { 1 } { n } \ sum _ { k = 1 } ^ n f ( x + k ^ 2 ) $. we show that $ a _ n $ satisfies a local scale - free $ \ ell ^ { p } $ - improving estimate, for $ 3 / 2 < p \ leq 2 $ : \ begin { equation * } n ^ { - 2 / p ' } \ lvert a _ n f \ rvert _ { p ' } \ lesssim n ^ { - 2 / p } \ lvert f \ rvert _ { \ ell ^ { p } }, \ end { equation * } provided $ f $ is supported in some interval of length $ n ^ 2 $, and $ p ' = \ frac { p } { p - 1 } $ is the conjugate index. the inequality above fails for $ 1 < p < 3 / 2 $. the maximal function $ a f = \ sup _ { n \ geq 1 } | a _ nf | $ satisfies a similar sparse bound. novel weighted and vector valued inequalities for $ a $ follow. a critical step in the proof requires the control of a logarithmic average over $ q $ of a function $ g ( q, x ) $ counting the number of square roots of $ x $ mod $ q $. one requires an estimate uniform in $ x $.
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arxiv:1907.05734
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we examine the origin of radial and vertical gradients in the age / metallicity of the stellar component of a galaxy disc formed in the apostle cosmological hydrody - namical simulations. some of these gradients resemble those in the milky way, where they have sometimes been interpreted as due to internal evolution, such as scattering off giant molecular clouds, radial migration driven by spiral patterns, or orbital reso - nances with a bar. secular processes play a minor role in the simulated galaxy, which lacks strong spiral or bar patterns, and where such gradients arise as a result of the gradual enrichment of a gaseous disc that is born thick but thins as it turns into stars and settles into centrifugal equilibrium. the settling is controlled by the feedback of young stars ; which links the star formation, enrichment, and equilibration timescales, inducing radial and vertical gradients in the gaseous disc and its descendent stars. the kinematics of coeval stars evolve little after birth and provide a faithful snapshot of the gaseous disc structure at the time of their formation. in this interpretation, the age - velocity dispersion relation would reflect the gradual thinning of the disc rather than the importance of secular orbit scattering ; the outward flaring of stars would result from the gas disc flare rather than from radial migration ; and vertical gradients would arise because the gas disc gradually thinned as it enriched. such radial and vertical trends might just reflect the evolving properties of the parent gaseous disc, and are not necessarily the result of secular evolutionary processes.
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arxiv:1709.01040
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understanding the relationship between vocal tract motion during speech and the resulting acoustic signal is crucial for aided clinical assessment and developing personalized treatment and rehabilitation strategies. toward this goal, we introduce an audio - to - video generation framework for creating real time / cine - magnetic resonance imaging ( rt - / cine - mri ) visuals of the vocal tract from speech signals. our framework first preprocesses rt - / cine - mri sequences and speech samples to achieve temporal alignment, ensuring synchronization between visual and audio data. we then employ a modified stable diffusion model, integrating structural and temporal blocks, to effectively capture movement characteristics and temporal dynamics in the synchronized data. this process enables the generation of mri sequences from new speech inputs, improving the conversion of audio into visual data. we evaluated our framework on healthy controls and tongue cancer patients by analyzing and comparing the vocal tract movements in synthesized videos. our framework demonstrated adaptability to new speech inputs and effective generalization. in addition, positive human evaluations confirmed its effectiveness, with realistic and accurate visualizations, suggesting its potential for outpatient therapy and personalized simulation of vocal tract visualizations.
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arxiv:2503.12102
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the ieee low - power image recognition challenge ( lpirc ) is an annual competition started in 2015 that encourages joint hardware and software solutions for computer vision systems with low latency and power. track 1 of the competition in 2018 focused on the innovation of software solutions with fixed inference engine and hardware. this decision allows participants to submit models online and not worry about building and bringing custom hardware on - site, which attracted a historically large number of submissions. among the diverse solutions, the winning solution proposed a quantization - friendly framework for mobilenets that achieves an accuracy of 72. 67 % on the holdout dataset with an average latency of 27ms on a single cpu core of google pixel2 phone, which is superior to the best real - time mobilenet models at the time.
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arxiv:1903.06791
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an efficient procedure for the computation of the coefficients of legendre expansions is here presented. we prove that the legendre coefficients associated with a function f ( x ) can be represented as the fourier coefficients of an abel - type transform of f ( x ). the computation of n legendre coefficients can then be performed in o ( n log n ) operations with a single fast fourier transform of the abel - type transform of f ( x ).
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arxiv:1106.0463
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the number of known, bright ( $ i < 18 $ ), high - redshift ( $ z > 2. 5 $ ) qsos in the southern hemisphere is considerably lower than the corresponding number in the northern hemisphere due to the lack of multi - wavelength surveys at $ \ delta < 0 $. recent works, such as the qubrics survey, successfully identified new, high - redshift qsos in the south by means of a machine learning approach applied on a large photometric dataset. building on the success of qubrics, we present a new qso selection method based on the probabilistic random forest ( prf ), an improvement of the classic random forest algorithm. the prf takes into account measurement errors, treating input data as probability distribution functions : this allows us to obtain better accuracy and a robust predictive model. we applied the prf to the same photometric dataset used in qubrics, based on the skymapper dr1, gaia dr2, 2mass, wise and galex databases. the resulting candidate list includes $ 626 $ sources with $ i < 18 $. we estimate for our proposed algorithm a completeness of $ \ sim84 \ % $ and a purity of $ \ sim78 \ % $ on the test datasets. preliminary spectroscopic campaigns allowed us to observe 41 candidates, of which 29 turned out to be $ z > 2. 5 $ qsos. the performances of the prf, currently comparable to those of the cca, are expected to improve as the number of high - z qsos available for the training sample grows : results are however already promising, despite this being one of the first applications of this method to an astrophysical context.
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arxiv:2106.12990
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recent progress on the structure and dynamics of bulges is reviewed. those aspects that link galaxy bulges either to oblate spheroids akin to elliptical galaxies or to rapidly - rotating, flattened systems more nearly resembling the products of disk internal transformations, are highlighted. the analysis of surface brightness profiles derived from hst data is reviewed to show that unresolved nuclear components detected by hst have biased the determination of surface brightness profiles obtained from the ground ; r ^ 1 / 4 profiles are virtually nonexistent in galaxy bulges. predictions from accretion n - body models on the shape of surface brightness profiles are discussed. the position of bulges on the fundamental plane of elliptical galaxies is examined to infer clues on bulge population ages and bulge dynamical structure. kinematic diagnostics on the internal dynamics of bulges are examined. finally, a new approach to the kinematic analysis of galaxies, based on the use of synthetic spectra of single stellar population models instead of the standard stellar templates, is presented.
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arxiv:astro-ph/0301647
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nonlinear sigma models appear in a wide variety of physics contexts, such as the long - range order with spontaneously broken continuous global symmetries. there are also large classes of quantum criticality admit sigma model descriptions in their phase diagrams without known ultraviolet complete quantum field theory descriptions. we investigate defects in general nonlinear sigma models in any spacetime dimensions, which include the " electric " defects that are characterized by topological interactions on the defects, and the " magnetic " defects that are characterized by the isometries and homotopy groups. we use an analogue of the charge - flux attachment to show that the magnetic defects are in general non - invertible, and the electric and magnetic defects form junctions that combine defects of different dimensions into analogues of higher - group symmetry. we explore generalizations that couple nonlinear sigma models to topological quantum field theories by defect attachment, which modifies the non - invertible fusion and braiding of the defects. we discuss several applications, including constraints on energy scales and scenarios of low energy dynamics with spontaneous symmetry breaking in gauge theories, and axion gauge theories.
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arxiv:2212.08608
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this paper considers the suitability of a number of emerging and future instruments for the study of radio recombination lines ( rrls ) at frequencies below 200 mhz. these lines arise only in low - density regions of the ionized interstellar medium, and they may represent a frequency - dependent foreground for next - generation experiments trying to detect h i signals from the epoch of reionization and dark ages ( " 21 - cm cosmology " ). we summarize existing decametre - wavelength observations of rrls, which have detected only carbon rrls. we then show that, for an interferometric array, the primary instrumental factor limiting detection and study of the rrls is the areal filling factor of the array. we consider the long wavelength array ( lwa - 1 ), the low frequency array ( lofar ), the low - frequency component of the square kilometre array ( ska - lo ), and a future lunar radio array ( lra ), all of which will operate at decametre wavelengths. these arrays offer digital signal processing, which should produce more stable and better defined spectral bandpasses ; larger frequency tuning ranges ; and better angular resolution than that of the previous generation of instruments that have been used in the past for rrl observations. detecting galactic carbon rrls, with optical depths at the level of 10 ^ - 3, appears feasible for all of these arrays, with integration times of no more than 100 hr. the ska - lo and lra, and the lwa - 1 and lofar at the lowest frequencies, should have a high enough filling factor to detect lines with much lower optical depths, of order 10 ^ - 4 in a few hundred hours. the amount of rrl - hosting gas present in the galaxy at the high galactic latitudes likely to be targeted in 21 - cm cosmology studies is currently unknown. if present, however, the spectral fluctuations from rrls could be comparable to or exceed the anticipated h i signals.
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arxiv:1010.0292
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intense few - to - sub - femtosecond soft x - ray pulses can produce neutral, two - site excited double - core - hole states by promoting two core electrons to the same unoccupied molecular orbital. we theoretically investigate double nitrogen k - edge excitations of nitrous oxide ( n2o ) with multiconfigurational electronic structure calculations. we show that the second core - excitation energy is reduced with respect to its ground state value. a site - selective double core - excitation mechanism using intense few - femtosecond x - rays is investigated using time - dependent schrodinger equation ( tdse ) simulations. the subsequent two - step auger - meitner and two - electrons - one - electron decay spectra of the double core - excited states are analyzed using a mulliken population analysis of the multiconfirational wavefunctions. the change in the electron emission lineshape between the absorption of 1 or 2 photons in the resonant core - excitation is predicted by combining this approach with the tdse simulations. we examine the possibility of resolving the double core - excited states with x - ray pump - probe techniques by calculating the chemical shifts of the core - electron binding energy of the core - excited states and decay products.
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arxiv:2208.05307
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we study a large - dimensional dynamic factor model where : ( i ) ~ the vector of factors $ \ mathbf f _ t $ is $ i ( 1 ) $ and driven by a number of shocks that is smaller than the dimension of $ \ mathbf f _ t $ ; and, ( ii ) ~ the idiosyncratic components are either $ i ( 1 ) $ or $ i ( 0 ) $. under ~ ( i ), the factors $ \ mathbf f _ t $ are cointegrated and can be modeled as a vector error correction model ( vecm ). under ( i ) and ( ii ), we provide consistent estimators, as both the cross - sectional size $ n $ and the time dimension $ t $ go to infinity, for the factors, the loadings, the shocks, the coefficients of the vecm and therefore the impulse - response functions ( irf ) of the observed variables to the shocks. ~ furthermore : possible deterministic linear trends are fully accounted for, and the case of an unrestricted var in the levels $ \ mathbf f _ t $, instead of a vecm, is also studied. the finite - sample properties the proposed estimators are explored by means of a montecarlo exercise. finally, we revisit two distinct and widely studied empirical applications. by correctly modeling the long - run dynamics of the factors, our results partly overturn those obtained by recent literature. specifically, we find that : ( i ) oil price shocks have just a temporary effect on us real activity ; and, ( ii ) in response to a positive news shock, the economy first experiences a significant boom, and then a milder recession.
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arxiv:1602.02398
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enhancing the reasoning capabilities of large language models ( llms ) typically relies on massive computational resources and extensive datasets, limiting accessibility for resource - constrained settings. our study investigates the potential of reinforcement learning ( rl ) to improve reasoning in small llms, focusing on a 1. 5 - billion - parameter model, deepseek - r1 - distill - qwen - 1. 5b, under strict constraints : training on 4 nvidia a40 gpus ( 48 gb vram each ) within 24 hours. adapting the group relative policy optimization ( grpo ) algorithm and curating a compact, high - quality mathematical reasoning dataset, we conducted three experiments to explore model behavior and performance. our results demonstrate rapid reasoning gains - e. g., amc23 accuracy rising from 63 % to 80 % and aime24 reaching 46. 7 %, surpassing o1 - preview - using only 7, 000 samples and a $ 42 training cost, compared to thousands of dollars for baseline models. however, challenges such as optimization instability and length constraints emerged with prolonged training. these findings highlight the efficacy of rl - based fine - tuning for small llms, offering a cost - effective alternative to large - scale approaches. we release our code and datasets as open - source resources, providing insights into trade - offs and laying a foundation for scalable, reasoning - capable llms in resource - limited environments. all are available at https : / / github. com / knoveleng / open - rs.
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arxiv:2503.16219
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partial quenching allows one to consider correlation functions and amplitudes that do not arise in the corresponding unquenched theory. for example, physical $ s $ - wave pion scattering can be decomposed into $ i = 0 $ and $ 2 $ amplitudes, while, in a partially - quenched extension, the larger symmetry group implies that there are more than two independent scattering amplitudes. it has been proposed that the finite - volume quantization condition of l \ " uscher holds for the correlation functions associated with each of the two - particle amplitudes that arise in partially - quenched theories. using partially - quenched chiral perturbation theory, we show that this proposal fails for those correlation functions for which the corresponding one - loop amplitudes do not satisfy $ s $ - wave unitarity. for partially - quenched amplitudes that, while being unphysical, do satisfy one - loop $ s $ - wave unitarity, we argue that the proposal is plausible. implications for previous work are discussed.
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arxiv:2107.09742
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we study the existence of zero - cycles of degree one on varieties that are defined over a function field of a curve over a complete discretely valued field. in particular, we show that local - global principles hold for such zero - cycles provided that local - global principles hold for the existence of rational points over extensions of the function field. this assertion is analogous to a known result concerning varieties over number fields. we also show that our results hold more generally in the henselian case.
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arxiv:1710.03173
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in - context learning ( icl ) enables large vision - language models ( lvlms ) to adapt to new tasks without parameter updates, using a few demonstrations from a large support set. however, selecting informative demonstrations leads to high computational and memory costs. while some methods explore selecting a small and representative coreset in the text classification, evaluating all support set samples remains costly, and discarded samples lead to unnecessary information loss. these methods may also be less effective for image classification due to differences in feature spaces. given these limitations, we propose key - based coreset optimization ( keco ), a novel framework that leverages untapped data to construct a compact and informative coreset. we introduce visual features as keys within the coreset, which serve as the anchor for identifying samples to be updated through different selection strategies. by leveraging untapped samples from the support set, we update the keys of selected coreset samples, enabling the randomly initialized coreset to evolve into a more informative coreset under low computational cost. through extensive experiments on coarse - grained and fine - grained image classification benchmarks, we demonstrate that keco effectively enhances icl performance for image classification task, achieving an average improvement of more than 20 \ %. notably, we evaluate keco under a simulated online scenario, and the strong performance in this scenario highlights the practical value of our framework for resource - constrained real - world scenarios.
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arxiv:2504.14200
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it is shown that, in spite of the appearances, the standard expression for the oscillation probability of ultrarelativistic neutrinos is lorentz invariant.
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arxiv:physics/0305122
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massive galaxies at higher redshifts ( $ \ emph { z } $ $ > $ 2 ) show different characteristics from their local counterparts : they are compact and most likely have a disk. in this study, we trace the evolution of local massive galaxies by performing a detailed morphological analysis, namely, fitting single s \ ' { e } rsic profiles and performing bulge + disk decompositions. we analyze $ \ sim $ 250 massive galaxies selected from all candels fields ( cosmos, uds, egs, goods - south and goods - north ). we confirm that both star - forming and quiescent galaxies increase their sizes significantly from $ \ emph { z } $ $ \ approx $ 2. 5 to the present day. the global s \ ' { e } rsic index of quiescent galaxies increases over time ( from $ n $ $ \ approx $ 2. 5 to $ n $ $ > $ 4 ), while that of star - forming galaxies remains roughly constant ( $ n $ $ \ approx $ 2. 5 ). by decomposing galaxy profiles into bulge + disk components, we find that massive galaxies at high redshift have prominent stellar disks, which are also evident from visual inspection of the images. by $ z $ $ \ approx $ 0. 5, the majority of the disks disappear and massive quiescent galaxies begin to resemble the local elliptical galaxies. star - forming galaxies have lower bulge - to - total ratios ( $ b / t $ ) than their quiescent counterparts at each redshift bin. the bulges of star - forming and quiescent galaxies follow different evolutionary histories, while their disks evolve similarly. we conclude that major mergers, along with minor mergers, have played a crucial role in the significant size increase of high - \ emph { z } galaxies and the destruction of their massive and large - scale disks.
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arxiv:1606.07571
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a graduate programme in msc engineering business management. in canada, memorial university of newfoundland has started a complete master ' s degree program in engineering management. in denmark, the technical university of denmark offers a msc program in engineering management ( in english ). in pakistan, university of engineering and technology, taxila, university of engineering and technology, lahore and national university of science and technology ( nust ) offer admission both at master and doctorate level in engineering management while capital university of science & technology ( cust ), ned university of engineering & technology, karachi and ghulam ishaq khan institute of engineering sciences and technology have been running a master of engineering / ms in engineering management program. a variant of this program is within quality management. comsats ( ciit ) offers a msc project management program to local and overseas pakistanis as an on - campus / off - campus student. in italy, the first engineering management program was established in 1972 at the university of calabria by beniamino andreatta. politecnico di milano offers degrees in management engineering., among many other public or private ( and publicly - accredited ) universities belonging to the same post - secondary academic degrees ' classification. in morocco, ecole nationale superieure des mines de rabat offers an engineering management degree ( three years of study full time with a selective admission for associate or bachelor degree holders ). the degree offered is referred to locally as diplome d ' ingenieur and is equivalent to master level degree. in russia, since 2014 the faculty of engineering management of the russian presidential academy of national economy and public administration ( ranepa ) offers bachelor ' s and master ' s degrees in engineering management. in france, the epf will offer, from january 2018, a 2 - year engineering & management major in english for the 4th and 5th years of its 5 - year engineering master ' s degree. the final two years are open to students who have completed an undergraduate engineering degree elsewhere. = = areas of practice = = engineering management is a broad field and can cover a wide range of technical and managerial topics. an important resource is the engineering management body of knowledge ( embok ). the topics below are representative of typical topics in the field. = = = leadership and organization management = = = leadership and organization management are concerned with the skills involving positive direction of technical organizations and motivation of employees. often a manager must shape engineering policy within an organization. = = = operations, operations research, and supply chain = = = operations management is concerned with designing and
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https://en.wikipedia.org/wiki/Engineering_management
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in this paper, based on results of exact learning and test theory, we study arbitrary infinite binary information systems each of which consists of an infinite set of elements and an infinite set of two - valued functions ( attributes ) defined on the set of elements. we consider the notion of a problem over information system, which is described by a finite number of attributes : for a given element, we should recognize values of these attributes. as algorithms for problem solving, we consider decision trees of two types : ( i ) using only proper hypotheses ( an analog of proper equivalence queries from exact learning ), and ( ii ) using both attributes and proper hypotheses. as time complexity, we study the depth of decision trees. in the worst case, with the growth of the number of attributes in the problem description, the minimum depth of decision trees of both types either is bounded from above by a constant or grows as a logarithm, or linearly. based on these results and results obtained earlier for attributes and arbitrary hypotheses, we divide the set of all infinite binary information systems into seven complexity classes.
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arxiv:2201.04506
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predicting human displacements is crucial for addressing various societal challenges, including urban design, traffic congestion, epidemic management, and migration dynamics. while predictive models like deep learning and markov models offer insights into individual mobility, they often struggle with out - of - routine behaviours. our study introduces an approach that dynamically integrates individual and collective mobility behaviours, leveraging collective intelligence to enhance prediction accuracy. evaluating the model on millions of privacy - preserving trajectories across three us cities, we demonstrate its superior performance in predicting out - of - routine mobility, surpassing even advanced deep learning methods. spatial analysis highlights the model ' s effectiveness near urban areas with a high density of points of interest, where collective behaviours strongly influence mobility. during disruptive events like the covid - 19 pandemic, our model retains predictive capabilities, unlike individual - based models. by bridging the gap between individual and collective behaviours, our approach offers transparent and accurate predictions, crucial for addressing contemporary mobility challenges.
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arxiv:2404.02740
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with view to applications, we establish a correspondence between two problems : ( i ) the problem of finding continuous positive definite extensions of functions $ f $ which are defined on open bounded domains $ \ omega $ in $ \ mathbb { r } $, on the one hand ; and ( ii ) spectral theory for elliptic differential operators acting on $ \ omega $, ( constant coefficients. ) a novelty in our approach is the use of a reproducing kernel hilbert space $ \ mathscr { h } _ { f } $ computed directly from $ \ left ( \ omega, f \ right ) $, as well as algorithms for computing relevant orthonormal bases in $ \ mathscr { h } _ { f } $.
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arxiv:1403.0619
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graph matching, also known as network alignment, refers to finding a bijection between the vertex sets of two given graphs so as to maximally align their edges. this fundamental computational problem arises frequently in multiple fields such as computer vision and biology. recently, there has been a plethora of work studying efficient algorithms for graph matching under probabilistic models. in this work, we propose a new algorithm for graph matching : our algorithm associates each vertex with a signature vector using a multistage procedure and then matches a pair of vertices from the two graphs if their signature vectors are close to each other. we show that, for two erd \ h { o } s - - r \ ' enyi graphs with edge correlation $ 1 - \ alpha $, our algorithm recovers the underlying matching exactly with high probability when $ \ alpha \ le 1 / ( \ log \ log n ) ^ c $, where $ n $ is the number of vertices in each graph and $ c $ denotes a positive universal constant. this improves the condition $ \ alpha \ le 1 / ( \ log n ) ^ c $ achieved in previous work.
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arxiv:2101.11783
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solving optimal control problems for transport - dominated partial differential equations ( pdes ) can become computationally expensive, especially when dealing with high - dimensional systems. to overcome this challenge, we focus on developing and deriving reduced - order models that can replace the full pde system in solving the optimal control problem. specifically, we explore the use of the shifted proper orthogonal decomposition ( pod ) as a reduced - order model, which is particularly effective for capturing high - fidelity, low - dimensional representations of transport - dominated phenomena. furthermore, we propose two distinct frameworks for addressing these problems : one where the reduced - order model is constructed first, followed by optimization of the reduced system, and another where the original pde system is optimized first, with the reduced - order model subsequently applied to the optimality system. we consider a 1d linear advection equation problem and compare the computational performance of the shifted pod method against the conventional methods like the standard pod when the reduced - order models are used as surrogates within a backtracking line search.
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arxiv:2412.18950
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in this paper, we use the mappings photoionization code to explore the physical parameters that impact on the measurement of electron temperature and abundance in hii regions. in the previous paper we presented observations and measurements of physical properties from the spectra of seventeen hii regions in fourteen isolated dwarf irregular galaxies from the sigrid sample. here, we analyze these observations further, together with three additional published data sets. we explore the effects of optical thickness, electron density, ionization parameter, ionization source, and non - equilibrium effects on the relation between electron temperature and metallicity. we present a standard model that fits the observed data remarkably well at metallicities between 1 / 10 and 1 solar. we investigate the effects of optically thin hii regions, and show that they can have a considerable effect on the measured electron temperature, and that there is evidence that some of the observed objects are optically thin. we look at the role of the ionization parameter and find that lower ionization parameter values give better fits at higher oxygen abundance. we show that higher pressures combined with low optical depth, and also kappa electron energy distributions at low kappa values, can generate the apparent high electron temperatures in low metallicity hii regions, and that the former provides the better fit to observations. we examine the effects of these parameters on the strong line diagnostic methods. we extend this to three - dimensional diagnostic grids to confirm how well the observations are described by the grids.
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arxiv:1405.7170
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and we suggest future observations to probe this and similar galaxies.
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arxiv:0912.2575
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we derive the deformed sl ( 2 ) gaudin model with integrable boundaries. starting from the jordanian deformation of the sl ( 2 ) - invariant yang r - matrix and generic solutions of the associated reflection equation and the dual reflection equation, the corresponding inhomogeneous spin - 1 / 2 xxx chain is obtained. the quasi - classical expansion of the transfer matrix yields the deformed sl ( 2 ) gaudin hamiltonians with boundary terms.
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arxiv:1304.6918
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we report on a search for new low - surface - brightness galaxies ( lsbgs ) using sloan digital sky survey ( sdss ) data within the gama equatorial fields. the search method consisted of masking objects detected with sdss photo, combining gri images weighted to maximise the expected signal - to - noise ratio ( snr ), and smoothing the images. the processed images were then run through a detection algorithm that finds all pixels above a set threshold and groups them based on their proximity to one another. the list of detections was cleaned of contaminants such as diffraction spikes and the faint wings of masked objects. from these, selecting potentially the brightest in terms of total flux, a list of 343 lsbgs was produced having been confirmed using vista kilo - degree infrared galaxy survey ( viking ) imaging. the photometry of this sample was refined using the deeper viking z band as the aperture - defining band. measuring their $ g - i $ and $ j - k $ colours shows that most are consistent with being at redshifts less than 0. 2. the photometry is carried out using an auto aperture for each detection giving surface brightnesses of $ \ mu _ { r } \ ge 25 \, \ mathrm { mag } \, \ mathrm { arcsec } ^ { - 2 } $ and magnitudes of $ r > 19. 8 $ mag. none of these galaxies are bright enough to be within the gama main survey limit but could be part of future deeper surveys to measure the low - mass end of the galaxy stellar mass function.
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arxiv:1609.01162
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set with no element, the empty set ( or null set ) that is denoted ∅, ∅ { \ displaystyle \ varnothing, \ emptyset }, or { }. { \ displaystyle \ { \, \ }. } a singleton is a set with exactly one element. if x { \ displaystyle x } is this element, the singleton is denoted { x }. { \ displaystyle \ { x \ }. } if x { \ displaystyle x } is itself a set, it must not be confused with { x }. { \ displaystyle \ { x \ }. } for example, ∅ { \ displaystyle \ emptyset } is a set with no elements, while { ∅ } { \ displaystyle \ { \ emptyset \ } } is a singleton with ∅ { \ displaystyle \ emptyset } as its unique element. a set is finite if there exists a natural number n { \ displaystyle n } such that the n { \ displaystyle n } first natural numbers can be put in one to one correspondence with the elements of the set. in this case, one says that n { \ displaystyle n } is the number of elements of the set. a set is infinite if such an n { \ displaystyle n } does not exist. the empty set is a finite set with 0 { \ displaystyle 0 } elements. the natural numbers form an infinite set, commonly denoted n { \ displaystyle \ mathbb { n } }. other examples of infinite sets include number sets that contain the natural numbers, real vector spaces, curves and most sorts of spaces. = = specifying a set = = extensionality implies that for specifying a set, one has either to list its elements or to provide a property that uniquely characterizes the set elements. = = = roster notation = = = roster or enumeration notation is a notation introduced by ernst zermelo in 1908 that specifies a set by listing its elements between braces, separated by commas. for example, one knows that { 4, 2, 1, 3 } { \ displaystyle \ { 4, 2, 1, 3 \ } } and { blue, white, red } { \ displaystyle \ { { \ text { blue, white, red } } \ } } denote sets and not tuples because of the enclosing braces. above notations { } { \ displaystyle \ { \, \ } } and { x } { \ displaystyle \ { x \ } }
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https://en.wikipedia.org/wiki/Set_(mathematics)
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conductor materials with good mechanical performance as well as high electrical - and thermal - conductivities are particularly important to break through the current bottle - neck limit ( $ \ sim 100 $ t ) of pulsed magnets. here we perform systematic studies on the elastic properties of the cu - 6wt \ % ag alloy wires, a promising candidate material for the new - generation pulsed magnets, by employing two independent ultrasonic techniques - resonant ultrasound spectroscopy ( rus ) and ultrasound pulse - echo experiments. our rus measurements manifest that the elastic properties of the cu - 6wt \ % ag alloy wires can be improved by an electroplastic drawing procedure as compared with the conventional cold drawing. we also take this chance to test the availability of our newly - built ultrasound pulse - echo facility at wuhan national high magnetic field center ( whmfc, china ), and the results suggest that the elastic performance of the electroplastically - drawn cu - 6wt \ % ag alloy wire remains excellent without anomalous softening under extreme conditions, e. g., ultra - high magnetic field up to 50 t, nitrogen / helium cryogenic liquids.
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arxiv:2410.09376
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interview has been regarded as one of the most crucial step for recruitment. to fully prepare for the interview with the recruiters, job seekers usually practice with mock interviews between each other. however, such a mock interview with peers is generally far away from the real interview experience : the mock interviewers are not guaranteed to be professional and are not likely to behave like a real interviewer. due to the rapid growth of online recruitment in recent years, recruiters tend to have online interviews, which makes it possible to collect real interview data from real interviewers. in this paper, we propose a novel application named ezinterviewer, which aims to learn from the online interview data and provides mock interview services to the job seekers. the task is challenging in two ways : ( 1 ) the interview data are now available but still of low - resource ; ( 2 ) to generate meaningful and relevant interview dialogs requires thorough understanding of both resumes and job descriptions. to address the low - resource challenge, ezinterviewer is trained on a very small set of interview dialogs. the key idea is to reduce the number of parameters that rely on interview dialogs by disentangling the knowledge selector and dialog generator so that most parameters can be trained with ungrounded dialogs as well as the resume data that are not low - resource. evaluation results on a real - world job interview dialog dataset indicate that we achieve promising results to generate mock interviews. with the help of ezinterviewer, we hope to make mock interview practice become easier for job seekers.
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arxiv:2301.00972
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rcc institute of technology ( rcc ) was founded as the radio college of canada in 1928, making it one of the oldest private technology institutions in canada. it is also the only private educational institute in ontario to be approved by the ministry of training, colleges and universities to grant bachelor ' s degrees. in 2018, yorkville university acquired rcc institute of technology. it was amalgamated with yorkville to become yorkville university / ontario. = = history = = radio college of canada ( rcc ) was founded in 1928 by j. c. wilson, who had previously amassed considerable radio experience in england and the united states. at the same time he established rcc publications, which continues to supply technical data to service technicians in canada. in 1930, as reported by the globe newspaper, rogers - majestic corporation and radio college of canada established a plan for registering radio servicemen of the entire dominion. examining and qualifying those who wished to become registered became rcc ' s role. in 1937 the college was acquired by r. christopher dobson. shortly thereafter, additional and more advanced training programs were added, including courses in commercial radio operation. during this period the demand for radio operators increased sharply with the growth in aviation ; consequently large classes of radio operators were trained for the federal department of transport. in the 1940s canada ' s contribution to the world war ii effort required immediate and large - scale planning to ensure an adequate and continuing supply of well - trained technicians and operators. training for canada and allied governments was performed for essential services such as government departments, merchant marines, and, of course, the important manufacturing industry. radio college established additional facilities and developed specialized training programs for the purpose. several classes of women radio operators for the air stations established across the country by the commonwealth air training scheme were trained. the students, who came from all parts of canada, were selected by aptitude tests developed by the college. radio college also furnished room, board, nursing and general supervision. after the war the college did extensive rehabilitation training for canadian and united states veterans, and later for civilians under government auspices. many merchant marine graduates of rcc have later requested from the college proof of their graduation and marine placement, thereby entitling them to the federal pension recently granted to world war ii members of the merchant marine. when television started in the 1950s, the college trained factory and service personnel. the college developed a new concept in electronics education, electronic engineering technology, a high - level program designed to train " technologists " who would be equipped to assist professional engineers in matters of applied
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https://en.wikipedia.org/wiki/RCC_Institute_of_Technology
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this paper is the final step in solving the problem of starlikeness of teichmuller spaces in bers ' embedding. this step concerns the case of finite dimensional teichmuller spaces $ { \ mathbf t } ( g, n ) $ of positive dimension ( corresponding to punctured riemann surfaces of finite conformal type $ ( g, n ) $ with $ 2g - 2 + n > 0 $ ).
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arxiv:2407.18239
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first, we state a generalization of the minimum - distance bound for pir codes. then we describe a construction for linear pir codes using packing designs and use it to construct some new 5 - pir codes. finally, we show that no encoder ( linear or nonlinear ) for the binary $ r $ - th order hamming code produces a 3 - pir code except when $ r = 2 $. we use these results to determine the smallest length of a binary ( possibly nonlinear ) 3 - pir code of combinatorial dimension up to ~ 6. a binary 3 - pir code of length 11 and size $ 2 ^ 7 $ is necessarily nonlinear, and we pose the existence of such a code as an open problem.
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arxiv:2208.14552
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a lattice reduction is an algorithm that transforms the given basis of the lattice to another lattice basis such that problems like finding a shortest vector and closest vector become easier to solve. some of the famous lattice reduction algorithms are lll and bkz reductions. we define a class of bases called \ emph { obtuse bases } and show that any lattice basis can be transformed to an obtuse basis in $ \ mathcal { o } ( n ^ 4 ) $ time. a shortest vector s can be written as $ v _ 1b _ 1 + \ cdots + v _ nb _ n $ where $ b _ 1, \ dots, b _ n $ are the input basis vectors and $ v _ 1, \ dots, v _ n $ are integers. when the input basis is obtuse, all these integers can be chosen to be positive for a shortest vector. this property of the obtuse basis makes lattice enumeration algorithm for finding a shortest vector exponentially faster. moreover, extreme pruning, the current fastest algorithm for lattice enumeration, can be run on an obtuse basis.
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arxiv:1912.01781
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given hilbert space operators $ p, t \ in b ( \ h ), p \ geq 0 $ invertible, $ t $ is $ ( m, p ) - $ expansive ( resp., $ ( m, p ) - $ isometric ) for some positive integer $ m $ if $ \ triangle _ { t ^ *, t } ^ m ( p ) = \ sum _ { j = 0 } ^ m ( - 1 ) ^ j \ left ( \ begin { array } { clcr } m \ \ j \ end { array } \ right ) { t ^ * } ^ jpt ^ j \ leq 0 $ ( resp., $ \ triangle _ { t ^ *, t } ^ m ( p ) = 0 $ ). an $ ( m, p ) - $ expansive operator $ t $ is power bounded if and only if it is a $ c _ { 1 \ cdot } - $ operator which is similar to an isometry and satisfies $ \ triangle _ { t ^ *, t } ^ n ( q ) = 0 $ for some positive invertible operator $ q \ in b ( \ h ) $ and all integers $ n \ geq 1 $. if, instead, $ t $ is an algebraic $ ( m, i ) - $ expansive operator, then either the spectral radius $ r ( t ) $ of $ t $ is greater than one or $ t $ is the perturbation of a unitary by a nilpotent such that $ t $ is $ ( 2n - 1, i ) - $ isometric for some positive integers $ m _ 0 \ leq m $, $ m _ 0 $ odd, and $ n \ geq \ frac { m _ 0 + 1 } { 2 } $.
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arxiv:2011.07847
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certain natural geometric approximation schemes are developed for wiener measure on a compact riemannian manifold. these approximations closely mimic the informal path integral formulas used in the physics literature for representing the heat semi - group on riemannian manifolds. the path space is approximated by finite dimensional manifolds consisting of piecewise geodesic paths adapted to partitions $ p $ of $ [ 0, 1 ] $. the finite dimensional manifolds of piecewise geodesics carry both an $ h ^ { 1 } $ and a $ l ^ { 2 } $ type riemannian structures $ g ^ i _ p $. it is proved that as the mesh of the partition tends to $ 0 $, $ $ 1 / z _ p ^ i e ^ { - 1 / 2 e ( \ sigma ) } vol _ { g ^ i _ p } ( \ sigma ) \ to \ rho _ i ( \ sigma ) \ nu ( \ sigma ) $ $ where $ e ( \ sigma ) $ is the energy of the piecewise geodesic path $ \ sigma $, and for $ i = 0 $ and $ 1 $, $ z _ p ^ i $ is a ` ` normalization ' ' constant, $ vol _ { g ^ i _ p } $ is the riemannian volume form relative $ g ^ i _ p $, and $ \ nu $ is wiener measure on paths on $ m $. here $ \ rho _ 1 = 1 $ and $ $ \ rho _ 0 ( \ sigma ) = \ exp ( - 1 / 6 \ int _ 0 ^ 1 scal ( \ sigma ( s ) ) ds ) $ $ where $ scal $ is the scalar curvature of $ m $. these results are also shown to imply the well know integration by parts formula for the wiener measure.
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arxiv:math/9807098
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clathrin - mediated endocytosis is the main pathway used by eukaryotic cells to take up extracellular material, but the dominant physical mechanisms driving this process are still elusive. recently several high - resolution imaging techniques have been used on different cell lines to measure the geometrical properties of clathrin - coated pits over their whole lifetime. here we first show that the combination of all datasets with the recently introduced cooperative curvature model defines a consensus pathway, which is characterized by a flat to - curved transition at finite area, followed by linear growth and subsequent saturation of curvature. we then apply an energetic model for the composite of plasma membrane and clathrin coat to this consensus pathway to show that the dominant mechanism for invagination could be coat stiffening, which might originate from cooperative interactions between the different clathrin molecules and progressively drives the system towards its intrinsic curvature. our theory predicts that two length scales determine the invagination pathway, namely the patch size at which the flat - to - curved transition occurs and the final pit radius.
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arxiv:2405.02820
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we present a framework for discriminative sequence classification where the learner works directly in the high dimensional predictor space of all subsequences in the training set. this is possible by employing a new coordinate - descent algorithm coupled with bounding the magnitude of the gradient for selecting discriminative subsequences fast. we characterize the loss functions for which our generic learning algorithm can be applied and present concrete implementations for logistic regression ( binomial log - likelihood loss ) and support vector machines ( squared hinge loss ). application of our algorithm to protein remote homology detection and remote fold recognition results in performance comparable to that of state - of - the - art methods ( e. g., kernel support vector machines ). unlike state - of - the - art classifiers, the resulting classification models are simply lists of weighted discriminative subsequences and can thus be interpreted and related to the biological problem.
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arxiv:1008.0528
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current multimodal models are well - suited for general visual understanding tasks. however, they perform inadequately when handling complex visual tasks related to human poses and actions, primarily due to the lack of specialized instruction - following data. we introduce a new method for generating such data by integrating human keypoints with traditional visual features like captions and bounding boxes. our approach produces datasets designed for fine - tuning models to excel in human - centric activities, focusing on three specific types : conversation, detailed description, and complex reasoning. we fine - tuned the llava - 7b model with this novel dataset, achieving significant improvements across various human pose - related tasks. experimental results show an overall improvement of 21. 18 % compared to the original llava - 7b model. these findings demonstrate the effectiveness of keypoints - assisted data in enhancing multimodal models.
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arxiv:2409.09306
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we present relations between x - ray luminosity and velocity dispersion ( l - sigma ), x - ray luminosity and gas mass ( l - mgas ), and cluster radius and velocity dispersion ( r500 - sigma ) for 62 galaxy clusters in the hiflugcs, an x - ray flux - limited sample minimizing bias toward any cluster morphology. our analysis in total is based on ~ 1. 3ms of clean x - ray xmm - newton data and 13439 cluster member galaxies with redshifts. cool cores are among the major contributors to the scatter in the l - sigma relation. when the cool - core - corrected x - ray luminosity is used the intrinsic scatter decreases to 0. 27 dex. even after the x - ray luminosity is corrected for the cool core, the scatter caused by the presence of cool cores dominates for the low - mass systems. the scatter caused by the non - cool - core clusters does not strongly depend on the mass range, and becomes dominant in the high - mass regime. the observed l - sigma relation agrees with the self - similar prediction, matches that of a simulated sample with agn feedback disregarding six clusters with < 45 cluster members with spectroscopic redshifts, and shows a common trend of increasing scatter toward the low - mass end, i. e., systems with sigma < 500km / s. a comparison of observations with simulations indicates an agn - feedback - driven impact in the low - mass regime. the best fits to the $ l - m _ { \ rm gas } $ relations for the disturbed clusters and undisturbed clusters in the observational sample closely match those of the simulated samples with and without agn feedback, respectively. this suggests that one main cause of the scatter is agn activity providing feedback in different phases, e. g., during a feedback cycle. the slope and scatter in the observed r500 - sigma relation is similar to that of the simulated sample with agn feedback except for a small offset but still within the scatter.
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arxiv:1011.3018
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scientific publishing is the means by which we communicate and share scientific knowledge, but this process currently often lacks transparency and machine - interpretable representations. scientific articles are published in long coarse - grained text with complicated structures, and they are optimized for human readers and not for automated means of organization and access. peer reviewing is the main method of quality assessment, but these peer reviews are nowadays rarely published and their own complicated structure and linking to the respective articles is not accessible. in order to address these problems and to better align scientific publishing with the principles of the web and linked data, we propose here an approach to use nanopublications as a unifying model to represent in a semantic way the elements of publications, their assessments, as well as the involved processes, actors, and provenance in general. to evaluate our approach, we present a dataset of 627 nanopublications representing an interlinked network of the elements of articles ( such as individual paragraphs ) and their reviews ( such as individual review comments ). focusing on the specific scenario of editors performing a meta - review, we introduce seven competency questions and show how they can be executed as sparql queries. we then present a prototype of a user interface for that scenario that shows different views on the set of review comments provided for a given manuscript, and we show in a user study that editors find the interface useful to answer their competency questions. in summary, we demonstrate that a unified and semantic publication model based on nanopublications can make scientific communication more effective and user - friendly.
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arxiv:2006.06348
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we explicitly calculate the scattering matrix at energy zero for attractive, radial and homogeneous long - range potentials. this proves a conjecture by derezinski and skibsted.
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arxiv:0812.2916
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remote control of experimental systems allows for improved collaboration between research groups as well as unique remote educational opportunities accessible by students and citizen scientists. here, we describe an experiment for the production and investigation of ultracold quantum gases capable of asynchronous remote control by multiple remote users. this is enabled by a queuing system coupled to an interface that can be modified to suit the user, e. g. a gamified interface for use by the general public or a scripted interface for an expert. to demonstrate this, the laboratory was opened to remote experts and the general public. during the available time, remote users were given the task of optimising the production of a bose - einstein condensate ( bec ). this work thus provides a stepping stone towards the exploration and realisation of more advanced physical models by remote experts, students and citizen scientists alike.
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arxiv:2101.11398
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the large n effective action of the non - linear sigma model based in the coset o ( n + 1 ) / o ( n ) is obtained. the renormalization of this effective action requires the introduction of an infinite set of counterterms. however, there exit particular cases where, at some scale, only a finite number of non - zero coupling constants are present. this fact makes possible a one parameter fit of the i = j = 0 low - energy pion scattering. the corresponding non - local effective action is used to study the properties of the skyrmion which is shown to be unstable in this approximation.
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arxiv:hep-ph/9401230
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most speaker verification tasks are studied as an open - set evaluation scenario considering the real - world condition. thus, the generalization power to unseen speakers is of paramount important to the performance of the speaker verification system. we propose to apply \ textit { mean teacher }, a temporal averaging model, to extract speaker embeddings with small intra - class variance and large inter - class variance. the mean teacher network refers to the temporal averaging of deep neural network parameters ; it can produces more accurate and stable representations than using weights after the training finished. by learning the reliable intermediate representation of the mean teacher network, we expect that the proposed method can explore more discriminatory embedding spaces and improve the generalization performance of the speaker verification system. experimental results on the voxceleb1 test set demonstrate that the proposed method relatively improves performance by 11. 61 \ %, compared to a baseline system.
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arxiv:2104.06604
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a simple analytical solution for the problem of multiphoton detachment from negative ions by a linearly polarized laser field is found. it is valid in the wide range of intensities and frequencies of the field, from the perturbation theory to the tunneling regime, and is applicable to the excess - photon as well as near - threshold detachment. practically, the formulae are valid when the number of photons is greater than two. they produce the total detachment rates, relative intensities of the excess - photon peaks, and photoelectron angular distributions for the hydrogen and halogen negative ions, in agreement with those obtained in other, more numerically involved calculations in both perturbative and non - perturbative regimes. our approach explains the extreme sensitivity of the multiphoton detachment probability to the asymptotic behaviour of the bound - state wave function. rapid oscillations in the angular dependence of the $ n $ - photon detachment probability are shown to arise due to interference of the two classical trajectories which lead to the same final state after the electron emerges at the opposite sides of the atom when the field is close to maximal.
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arxiv:physics/9702002
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petri nets ( pn ) are a central, theoretically sound model for concurrent or distributed systems but, at least in their classical definition, not expressive enough to represent dynamic reconfiguration capabilities. on the other side, rewriting logic has proved to be a natural semantic framework for several formal models of concurrent / distributed systems. we propose a compact, efficient maude formalization of dynamically reconfigurable pt nets ( with inhibitor arcs ), using as a running example the specification of a simple, fault - tolerant manufacturing system. we discuss the advantages of such a combined approach, as well as some concerns that it raises.
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arxiv:2111.08205
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a study of the interaction of loosely bound nuclei 6, 7li at 9 and 19 amev with light targets has been undertaken. with the determination of unambiguous optical potentials in mind, elastic data for four projectile - target combinations and one neutron transfer reaction 13c ( 7li, 8li ) 12c have been measured on a large angular range. the kinematical regime encompasses a region where the mean field ( optical potential ) has a marked variation with mass and energy, but turns out to be sufficiently surface transparent to allow strong refractive effects to be manifested in elastic scattering data at intermediate angles. the identified exotic feature, a " plateau " in the angular distributions at intermediate angles, is fully confirmed in four reaction channels and interpreted as a pre - rainbow oscillation resulting from the interference of the barrier and internal barrier farside scattering subamplitudes.
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arxiv:nucl-ex/0402011
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we report the application of the monte carlo simulation to phase separation dynamics. first, we deal with the phase separation under shear flow. the thermal effect on the phase separation is discussed, and the anisotropic growth exponents in the late stage are estimated. next, we study the effect of surfactants on the three - component solvents. we obtain the mixture of macrophase separation and microphase separation, and investigate the dynamics of both phase separations.
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arxiv:cond-mat/9912448
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in mathematics, the concept of a measure is a generalization and formalization of geometrical measures ( length, area, volume ) and other common notions, such as magnitude, mass, and probability of events. these seemingly distinct concepts have many similarities and can often be treated together in a single mathematical context. measures are foundational in probability theory, integration theory, and can be generalized to assume negative values, as with electrical charge. far - reaching generalizations ( such as spectral measures and projection - valued measures ) of measure are widely used in quantum physics and physics in general. the intuition behind this concept dates back to ancient greece, when archimedes tried to calculate the area of a circle. but it was not until the late 19th and early 20th centuries that measure theory became a branch of mathematics. the foundations of modern measure theory were laid in the works of emile borel, henri lebesgue, nikolai luzin, johann radon, constantin caratheodory, and maurice frechet, among others. = = definition = = let x { \ displaystyle x } be a set and σ { \ displaystyle \ sigma } a σ - algebra over x. { \ displaystyle x. } a set function μ { \ displaystyle \ mu } from σ { \ displaystyle \ sigma } to the extended real number line is called a measure if the following conditions hold : non - negativity : for all e ∈ σ, μ ( e ) ≥ 0. { \ displaystyle e \ in \ sigma, \ \ \ mu ( e ) \ geq 0. } μ ( ∅ ) = 0. { \ displaystyle \ mu ( \ varnothing ) = 0. } countable additivity ( or σ - additivity ) : for all countable collections { e k } k = 1 ∞ { \ displaystyle \ { e _ { k } \ } _ { k = 1 } ^ { \ infty } } of pairwise disjoint sets in σ, μ ( k = 1 ∞ e k ) = k = 1 ∞ μ ( e k ). { \ displaystyle \ mu { \ left ( \ bigcup _ { k = 1 } ^ { \ infty } e _ { k } \ right ) } = \ sum _ { k = 1 } ^ { \ infty } \ mu ( e _ { k } ). } if at least one set e { \ displaystyle e } has finite measure, then the requirement
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https://en.wikipedia.org/wiki/Measure_(mathematics)
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strong interaction between light and matter waves, such as electron beams in electron microscopes, has recently emerged as a new tool for understanding entanglement. here, we systematically investigate electron - light interactions from first principles. we show that enhanced coupling can be achieved for systems involving slow electron wavepackets interacting with plasmonic nanoparticles, due to simultaneous classical recoil and quantum mechanical photon absorption and emission processes. for slow electrons with longitudinal broadenings longer than the dimensions of nanoparticles, phase - matching between slow electrons and plasmonic oscillations is manifested as an additional degree of freedom to control the strength of coupling. our findings pave the way towards a systematic and realistic understanding of electron - light interactions beyond adiabatic approximations, and lay the ground for realization of entangled electron - photon systems and boson - sampling devices involving light and matter waves.
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arxiv:2003.14101
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we prove that the diagonal of the transition probabilities for the d - dimensional bessel processes on ( 0, 1 ], reflected at 1, which we denote by $ p _ r ^ n ( t, r, r ) $, is an increasing function of r for d > 2 and that this is false for d = 2.
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arxiv:0707.4299
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the focus of this work is on designing influencing strategies to shape the collective opinion of a network of individuals. we consider a variant of the voter model where opinions evolve in one of two ways. in the absence of external influence, opinions evolve via interactions between individuals in the network, while, in the presence of external influence, opinions shift in the direction preferred by the influencer. we focus on a finite time - horizon and an influencing strategy is characterized by when it exerts influence in this time - horizon given its budget constraints. prior work on this opinion dynamics model assumes that individuals take into account the opinion of all individuals in the network. we generalize this and consider the setting where the opinion evolution of an individual depends on a limited collection of opinions from the network. we characterize the nature of optimal influencing strategies as a function of the way in which this collection of opinions is formed.
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arxiv:2002.00664
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we consider the effect of inter - atom interactions on the condensation temperature $ t _ c $ of an atomic bose - einstein condensate. we find an analytic expression of the shift in $ t _ c $ induced by interactions with respect the ideal non - interacting case, in the mean - field and semi - classical approximations. such a shift is expressed in terms of the ratio $ a / \ lambda _ { t _ c } $ between the s - wave scattering length $ a $ and the thermal wavelength $ \ lambda _ { t _ c } $. this result is used to discuss the tension between mean - field predictions and observations in strongly interacting $ ^ { 39 } k $ condensates. it is shown that such a tension is solved taking into account the details of the feshbach resonance used to tune $ a $ in the experiments.
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arxiv:2210.10616
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recent advancements in llms have showcased their remarkable role - playing capabilities, able to accurately simulate the dialogue styles and cognitive processes of various roles based on different instructions and contexts. studies indicate that assigning llms the roles of experts, a strategy known as role - play prompting, can enhance their performance in the corresponding domains. however, the prompt needs to be manually designed for the given problem, requiring certain expertise and iterative modifications. to this end, we propose self - prompt tuning, making llms themselves generate role - play prompts through fine - tuning. leveraging the lima dataset as our foundational corpus, we employ gpt - 4 to annotate role - play prompts for each data points, resulting in the creation of the lima - role dataset. we then fine - tune llms like llama - 2 - 7b and mistral - 7b on lima - role. consequently, the self - prompt tuned llms can automatically generate expert role prompts for any given question. we extensively evaluate self - prompt tuned llms on widely used nlp benchmarks and open - ended question test. our empirical results illustrate that self - prompt tuned llms outperform standard instruction tuned baselines across most datasets. this highlights the great potential of utilizing fine - tuning to enable llms to self - prompt, thereby automating complex prompting strategies. we release the dataset, models, and code at this \ href { https : / / anonymous. 4open. science / r / self - prompt - tuning - 739e / } { url }.
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arxiv:2407.08995
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an $ ( n, r ) $ - covering sequence is a cyclic sequence whose consecutive $ n $ - tuples form a code of length $ n $ and covering radius $ r $. using several construction methods improvements of the upper bounds on the length of such sequences for $ n \ leq 20 $ and $ 1 \ leq r \ leq 3 $, are obtained. the definition is generalized in two directions. an $ ( n, m, r ) $ - covering sequence code is a set of cyclic sequences of length $ m $ whose consecutive $ n $ - tuples form a code of length ~ $ n $ and covering radius $ r $. the definition is also generalized to arrays in which the $ m \ times n $ sub - matrices form a covering code with covering radius $ r $. we prove that asymptotically there are covering sequences that attain the sphere - covering bound up to a constant factor.
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arxiv:2502.08424
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despite the immense societal importance of ethically designing artificial intelligence ( ai ), little research on the public perceptions of ethical ai principles exists. this becomes even more striking when considering that ethical ai development has the aim to be human - centric and of benefit for the whole society. in this study, we investigate how ethical principles ( explainability, fairness, security, accountability, accuracy, privacy, machine autonomy ) are weighted in comparison to each other. this is especially important, since simultaneously considering ethical principles is not only costly, but sometimes even impossible, as developers must make specific trade - off decisions. in this paper, we give first answers on the relative importance of ethical principles given a specific use case - the use of ai in tax fraud detection. the results of a large conjoint survey ( n = 1099 ) suggest that, by and large, german respondents found the ethical principles equally important. however, subsequent cluster analysis shows that different preference models for ethically designed systems exist among the german population. these clusters substantially differ not only in the preferred attributes, but also in the importance level of the attributes themselves. we further describe how these groups are constituted in terms of sociodemographics as well as opinions on ai. societal implications as well as design challenges are discussed.
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arxiv:2106.00326
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we investigate the influence of the finite extension and the aspherical geometry of a galaxy cluster on the estimate of the hubble constant through the sunyaev - zel ' dovich effect. an analysis of a recent chandra image of the galaxy cluster rbs797 indicates a strong ellipticity and thus a pronounced aspherical geometry. we estimate the total mass of rbs797 assuming spherical or ellipsoidal geometry and show that in the latter case the mass is about 10 - 17 % less than the one inferred for a spherical shape.
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arxiv:astro-ph/0108320
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we study reinforcement learning ( rl ) in settings where observations are high - dimensional, but where an rl agent has access to abstract knowledge about the structure of the state space, as is the case, for example, when a robot is tasked to go to a specific room in a building using observations from its own camera, while having access to the floor plan. we formalize this setting as transfer reinforcement learning from an abstract simulator, which we assume is deterministic ( such as a simple model of moving around the floor plan ), but which is only required to capture the target domain ' s latent - state dynamics approximately up to unknown ( bounded ) perturbations ( to account for environment stochasticity ). crucially, we assume no prior knowledge about the structure of observations in the target domain except that they can be used to identify the latent states ( but the decoding map is unknown ). under these assumptions, we present an algorithm, called tasid, that learns a robust policy in the target domain, with sample complexity that is polynomial in the horizon, and independent of the number of states, which is not possible without access to some prior knowledge. in synthetic experiments, we verify various properties of our algorithm and show that it empirically outperforms transfer rl algorithms that require access to " full simulators " ( i. e., those that also simulate observations ).
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arxiv:2205.14237
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we propose an optimization formulation for locational pricing of energy transported through a pipeline network that carries mixtures of natural gas and hydrogen from distributed sources to consumers. the objective includes the economic value provided by the pipeline to consumers of energy and suppliers of natural gas and green hydrogen, as well as incentives to lower carbon emissions by consuming the latter instead of the former. the optimization is subject to the physics of gas flow and mixing in the pipeline network as well as engineering limits. in addition to formulating this mathematical program, we synthesize the lagrangian and derive analytical expressions for the dual variables. we propose that the dual solution can be used to derive locational marginal prices of natural gas, hydrogen, and energy, as well as the decarbonization premium paid by consumers that receive hydrogen. we derive several properties of solutions obtained using the proposed market mechanism, and demonstrate them using case studies for standard 8 - node and 40 - node pipeline test networks. finally, we show that optimization - based analysis of the type proposed here is critical for making sound decisions about economic policy and infrastructure expansion for blending green hydrogen into existing natural gas pipelines.
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arxiv:2310.13181
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in classical general relativity, the generic approach to the initial singularity is usually understood in terms of the bkl scenario. in this scenario, along with the bianchi ix model, the exact, singular, kasner solution of vacuum bianchi i model also plays a pivotal role. using an effective classical hamiltonian obtained from loop quantization of vacuum bianchi i model, exact solution is obtained which is non - singular due to a discreteness parameter. the solution is parameterized in exactly the same manner as the usual kasner solution and reduces to the kasner solution as discreteness parameter is taken to zero. at the effective hamiltonian level, the avoidance of kasner singularity uses a mechanism distinct from the ` inverse volume ' modifications characteristic of loop quantum cosmology.
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arxiv:gr-qc/0505002
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different compaction processes of the nanosized granular system, which is a prototype of an alumina nanopowder, are studied by the granular dynamics method. for all processes : compaction curves ' ' density vs. pressure ' ' of the powder compact are calculated, the elastic and the plastic parts are extracted from the total deformation, the body elastic moduli are determined within the isotropic solid approximation. the inadequacy of the isotropy approximation is established. the nanopowder yield surface is constructed in the space of stress tensor invariants. the inapplicability of the traditional associated flow rule for description of oxide nanopowders compaction processes is revealed. an alternative flow rule is suggested.
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arxiv:2001.11674
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this study determines a useful value to use for the gap width of mechanical overlap joints in models of magnetic shielding. the average value of 0. 1 mm is found to agree with measurements.
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arxiv:1510.03846
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in this paper, we focus on the distributed set - membership filtering ( smfing ) problem for a multi - agent system with absolute ( taken from agents themselves ) and relative ( taken from neighbors ) measurements. in the literature, the relative measurements are difficult to deal with, and the smfs highly rely on specific set descriptions. as a result, establishing the general distributed smfing framework having relative measurements is still an open problem. to solve this problem, first, we provide the set description based on uncertain variables determined by the relative measurements between two agents as the foundation. surprisingly, the accurate description requires only a single calculation step rather than multiple iterations, which can effectively reduce computational complexity. based on the derived set description, called the uncertain range, we propose two distributed smfing frameworks : one calculates the joint uncertain range of the agent itself and its neighbors, while the other only computes the marginal uncertain range of each local system. furthermore, we compare the performance of our proposed two distributed smfing frameworks and the benchmark - - centralized smfing framework. a rigorous set analysis reveals that the distributed smf can be essentially considered as the process of computing the marginal uncertain range to outer bound the projection of the uncertain range obtained by the centralized smf in the corresponding subspace. simulation results corroborate the effectiveness of our proposed distributed frameworks and verify our theoretical analysis.
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arxiv:2305.15797
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convolutional neural networks ( cnns ) have reigned for a decade as the de facto approach to automated medical image diagnosis. recently, vision transformers ( vits ) have appeared as a competitive alternative to cnns, yielding similar levels of performance while possessing several interesting properties that could prove beneficial for medical imaging tasks. in this work, we explore whether it is time to move to transformer - based models or if we should keep working with cnns - can we trivially switch to transformers? if so, what are the advantages and drawbacks of switching to vits for medical image diagnosis? we consider these questions in a series of experiments on three mainstream medical image datasets. our findings show that, while cnns perform better when trained from scratch, off - the - shelf vision transformers using default hyperparameters are on par with cnns when pretrained on imagenet, and outperform their cnn counterparts when pretrained using self - supervision.
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arxiv:2108.09038
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the precise data for the total cross section $ \ sigma ( e ^ + e ^ - \ to { hadrons } ) $ from the charm threshold region, when combined with the evaluation of moments with three loop accuracy, lead to a direct determination of the short distance $ \ bar { \ rm ms } $ charm quark mass $ m _ c ( m _ c ) = 1. 304 ( 27 ) $. applying the same approach to the bottom quark we obtain $ m _ b ( m _ b ) = 4. 191 ( 51 ) $ gev. a complementary method for the determination of $ m _ b $ is based of the analysis of the $ \ upsilon ( 1s ) $ system which is confronted with a next - to - next - to - next - to - leading order calculation of the corresponding energy level. this leads to $ m _ b ( m _ b ) = 4. 346 ( 70 ) $ gev.
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arxiv:hep-ph/0211035
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recently, chain - of - thought ( cot ) prompting has delivered success on complex reasoning tasks, which aims at designing a simple prompt like ` ` let ' s think step by step ' ' or multiple in - context exemplars with well - designed rationales to elicit large language models ( llms ) to generate intermediate reasoning steps. however, the generated rationales often come with mistakes, making unfactual and unfaithful reasoning chains. to mitigate this brittleness, we propose a novel chain - of - knowledge ( cok ) prompting, where we aim at eliciting llms to generate explicit pieces of knowledge evidence in the form of structure triple. this is inspired by our human behaviors, i. e., we can draw a mind map or knowledge map as the reasoning evidence in the brain before answering a complex question. benefiting from cok, we additionally introduce a f ^ 2 - verification method to estimate the reliability of the reasoning chains in terms of factuality and faithfulness. for the unreliable response, the wrong evidence can be indicated to prompt the llm to rethink. extensive experiments demonstrate that our method can further improve the performance of commonsense, factual, symbolic, and arithmetic reasoning tasks.
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arxiv:2306.06427
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i construct a complete asymptotic expansion of solutions to the problem of linear stability of three - dimensional steady space - periodic magnetohydrodynamic states to perturbations involving large periods. eddy diffusivity tensor is derived for parity - invariant steady states. i present numerical evidences that if perturbations of the flow are permitted, then the effect of negative eddy diffusivity emerges at much larger magnetic molecular diffusivities than in the kinematic dynamo problem ( where no perturbations of the flow are assumed ).
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arxiv:nlin/0512076
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we study the effect of a massive central singularity on the structure of a triaxial galaxy using n - body simulations. starting from a single initial model, we grow black holes with various final masses mh and at various rates, ranging from impulsive to adiabatic. in all cases, the galaxy achieves a final shape that is nearly spherical at the center and close to axisymmetric throughout. however, the rate of change of the galaxy ' s shape depends strongly on the ratio mh / mg of black hole mass to galaxy mass. when mh / mg < 0. 3 %, the galaxy evolves in shape on a timescale that exceeds 100 orbital periods, or roughly a galaxy lifetime. when mh / mg > 2 %, the galaxy becomes axisymmetric in little more than a crossing time. we propose that the rapid evolution toward axisymmetric shapes that occurs when mh / mg > 2 % provides a negative feedback mechanism which limits the mass of central black holes by cutting off their supply of fuel.
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arxiv:astro-ph/9709106
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let c be a binary linear code and suppose that its automorphism group contains a non trivial subgroup g. what can we say about c knowing g? in this paper we collect some answers to this question in the cases g = c _ p, g = c _ 2p and g = d _ 2p ( p an odd prime ), with a particular regard to the case in which c is self - dual. furthermore we generalize some methods used in other papers on this subject. finally we give a short survey on the problem of determining the automorphism group of a putative self - dual [ 72, 36, 16 ] code, in order to show where these methods can be applied.
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arxiv:1311.3868
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in this paper, we consider low - rank approximations for the solutions to the stochastic helmholtz equation with random coefficients. a stochastic galerkin finite element method is used for the discretization of the helmholtz problem. existence theory for the low - rank approximation is established when the system matrix is indefinite. the low - rank algorithm does not require the construction of a large system matrix which results in an advantage in terms of cpu time and storage. numerical results show that, when the operations in a low - rank method are performed efficiently, it is possible to obtain an advantage in terms of storage and cpu time compared to computations in full rank. we also propose a general approach to implement a preconditioner using the low - rank format efficiently.
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arxiv:2302.08393
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a finite - time protocol for a multi - agent systems ( mass ) can guarantee the convergence of every agent in a finite time interval in contrast to the asymptotic convergence, but the settling time depends on the initial condition and design parameters and is inconsistent across the agents. in this paper, we study the prescribed - time cooperative output regulation ( ptcor ) problem for a class of linear heterogeneous mass under a directed communication graph, where the settling time of every agent can be specified a priori and thus consistent. as a special case of ptcor, the necessary and sufficient condition for prescribed - time output regulation of an individual system is first discussed. then, the ptcor problem is converted into two cascaded subsystem, where the first one composed of distributed estimate errors and local estimate errors and the second one is for local tracking errors. the criterion for prescribed - time stabilization of the cascaded system is proposed and is found to be different from that of traditional asymptotic stabilization of a cascaded system. under the criterion and sufficient condition, the general ptcor problem is studied in two scenarios including state feedback control and measurement output feedback control. in particular, a distributed prescribed - time observer for each subsystem is explicitly constructed to estimate the exosystem ' s state. based on the observer, a distributed controller is proposed to achieve convergence of the regulated output to zero within a prescribed - time.
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arxiv:2407.11408
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maximum distance separable ( mds ) and near maximum distance separable ( nmds ) codes have been widely used in various fields such as communication systems, data storage, and quantum codes due to their algebraic properties and excellent error - correcting capabilities. this paper focuses on a specific class of linear codes and establishes necessary and sufficient conditions for them to be mds or nmds. additionally, we employ the well - known schur method to demonstrate that they are non - equivalent to generalized reed - solomon codes.
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arxiv:2406.03693
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in this paper, we investigate the generalized pell sequence, the generalized complex pell sequence and the generalized dual pell sequence using the pell numbers. we obtain special cases of these sequences. furthermore, we give recurrence relations, vectors, the silver ratio and binet ' s formula for the above - investigated sequences.
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arxiv:1711.06260
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let $ n \ geqslant 4 $ be a natural number, and let $ k $ be a set $ k \ subseteq [ n ] : = { 1, 2,..., n } $. we study the problem to find the smallest possible size of a maximal family $ \ mathcal { a } $ of subsets of $ [ n ] $ such that $ \ mathcal { a } $ contains only sets whose size is in $ k $, and $ a \ not \ subseteq b $ for all $ { a, b } \ subseteq \ mathcal { a } $, i. e. $ \ mathcal { a } $ is an antichain. we present a general construction of such antichains for sets $ k $ containing 2, but not 1. if $ 3 \ in k $ our construction asymptotically yields the smallest possible size of such a family, up to an $ o ( n ^ 2 ) $ error. we conjecture our construction to be asymptotically optimal also for $ 3 \ not \ in k $, and we prove a weaker bound for the case $ k = { 2, 4 } $. our asymptotic results are straightforward applications of the graph removal lemma to an equivalent reformulation of the problem in extremal graph theory which is interesting in its own right.
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arxiv:1206.3007
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nonlinear systems are capable of displaying complex behavior even if this is the result of a small number of interacting time scales. a widely studied case is when complex dynamics emerges out of a nonlinear system being forced by a simple harmonic function. in order to identify if a recorded time series is the result of a nonlinear system responding to a simpler forcing, we develop a discrete nonlinear transformation for time series based on synchronization techniques. this allows a parameter estimation procedure which simultaneously searches for a good fit of the recorded data, and small complexity of a fluctuating driving parameter. we illustrate this procedure using data from respiratory patterns during birdsong production.
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arxiv:1410.8230
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using the notion of complete compactness introduced by h. saar, we define completely almost periodic functionals on completely contractive banach algebras. we show that, if $ ( m, \ gamma ) $ is a hopf - - von neumann algebra with $ m $ injective, then the space of completely almost periodic functionals on $ m _ \ ast $ is a $ c ^ \ ast $ - subalgebra of $ m $.
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arxiv:1011.4270
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list of military vehicles list of armoured fighting vehicles list of tanks military aircraft includes any use of aircraft by a country ' s military, including such areas as transport, training, disaster relief, border patrol, search and rescue, surveillance, surveying, peacekeeping, and ( very rarely ) aerial warfare. list of aircraft list of aircraft weapons warships are watercraft for combat and transportation in and on seas and oceans. submarines complex masting and sail systems found on warships during the age of sail list of historical ship and boat types list of aircraft carriers list of submarine classes = = = defence = = = fortifications are military constructions and buildings designed for defence in warfare. they range in size and age from the great wall of china to a sangar. list of fortifications list of forts = = = sensors and communication = = = sensors and communication systems are used to detect enemies, coordinate movements of armed forces and guide weaponry. early systems included flag signaling, telegraph and heliographs. laser guidance missile guidance norden bombsight proximity fuse radar satellite guidance in guidance weapons = = future technology = = the defense advanced research projects agency is an agency of the united states department of defense responsible for the development of new technologies for use by the military. darpa leads the development of military technology in the united states and today, has dozens of ongoing projects ; everything from humanoid robots to bullets that can change path before reaching their target. china has a similar agency. = = = emerging territory = = = current militaries continue to invest in new technologies for the future. such technologies include cognitive radar, 5g cellular networks, microchips, semiconductors, and large scale analytic engines. additionally, many militaries seek to improve current laser technology. for example, israeli defense forces utilize laser technology to disable small enemy machinery, but seek to move to more large scale capabilities in the coming years. militaries across the world continue to perform research on autonomous technologies which allow for increased troop mobility or replacement of live soldiers. autonomous vehicles and robots are expected to play a role in future conflicts ; this has the potential to decrease loss of life in future warfare. observers of transhumanism note high rates of technological terms in military literature, but low rates for explicitly transhuman - related terms. today ' s hybrid style of warfare also calls for investments in information technologies. increased reliance on computer systems has incentivized nations to push for increased efforts at managing large scale networks and having access to large scale data. new strategies of cyber and hybrid warfare includes, network attacks, media analysis
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https://en.wikipedia.org/wiki/Military_technology
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the general existence of $ p $ - dirichlet energy minimizing maps into $ q _ q ( l _ 2 ) $ is obtained.
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arxiv:1402.3497
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electron spin dynamics are studied in ga - doped zno single crystals by time - resolved faraday and kerr rotation spectroscopies. long - lived spin coherence with two dephasing processes is discovered where the characteristic time is up to 5. 2 ns at room temperature. through the dependence measurements of laser wavelength and temperature, the room - temperature long - lived spin signal is attributed to localized electrons. the spin dephasing ( relaxation ) processes are independent of transverse ( longitudinal ) magnetic fields, indicating the spin dephasing not resulting from the g - factor inhomogeneity and electron - nuclear hyperfine interaction. it reveals that the two spin dephasing processes originate from two types of localized electrons, both of which are dominated by the anisotropic exchange dzyaloshinskii - moriya interaction between adjacent localized electrons.
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arxiv:2103.01673
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reasoning models have demonstrated impressive performance on difficult tasks that traditional language models struggle at. however, many are plagued with the problem of overthinking - - generating large amounts of unnecessary tokens which don ' t improve accuracy on a question. we introduce approximate measures of problem - level difficulty and demonstrate that a clear relationship between problem difficulty and optimal token spend exists, and evaluate how well calibrated a variety of reasoning models are in terms of efficiently allocating the optimal token count. we find that in general, reasoning models are poorly calibrated, particularly on easy problems. to evaluate calibration on easy questions we introduce dumb500, a dataset of extremely easy math, reasoning, code, and task problems, and jointly evaluate reasoning model on these simple examples and extremely difficult examples from existing frontier benchmarks on the same task domain. finally, we introduce thoughtterminator, a training - free black box decoding technique that significantly improves reasoning model calibration.
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arxiv:2504.13367
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we investigate the stability of the synchronization manifold in a ring and an open - ended chain of nearest neighbors coupled self - sustained systems, each self - sustained system consisting of multi - limit cycles van der pol oscillators. such model represents, for instance, coherent oscillations in biological systems through the case of an enzymatic - substrate reaction with ferroelectric behavior in brain waves model. the ring and open - ended chain of identical and non - identical oscillators are considered separately. by using the master stability function approach ( for the identical case ) and the complex kuramoto order parameter ( for the non - identical case ), we derive the stability boundaries of the synchronized manifold. we have found that synchronization occurs in a system of many coupled modified van der pol oscillators and it is stable even in presence of a spread of parameters.
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arxiv:1001.3240
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referring expressions generation ( reg ) aims to produce textual descriptions that unambiguously identifies specific objects within a visual scene. traditionally, this has been achieved through supervised learning methods, which perform well on specific data distributions but often struggle to generalize to new images and concepts. to address this issue, we present a novel approach for reg, named disclip, short for discriminative clip. we build on clip, a large - scale visual - semantic model, to guide an llm to generate a contextual description of a target concept in an image while avoiding other distracting concepts. notably, this optimization happens at inference time and does not require additional training or tuning of learned parameters. we measure the quality of the generated text by evaluating the capability of a receiver model to accurately identify the described object within the scene. to achieve this, we use a frozen zero - shot comprehension module as a critique of our generated referring expressions. we evaluate disclip on multiple referring expression benchmarks through human evaluation and show that it significantly outperforms previous methods on out - of - domain datasets. our results highlight the potential of using pre - trained visual - semantic models for generating high - quality contextual descriptions.
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arxiv:2305.19108
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the meissner effect and the spin meissner effect are the spontaneous generation of charge and spin current respectively near the surface of a metal making a transition to the superconducting state. the meissner effect is well known but, i argue, not explained by the conventional theory, the spin meissner effect has yet to be detected. i propose that both effects take place in all superconductors, the first one in the presence of an applied magnetostatic field, the second one even in the absence of applied external fields. both effects can be understood under the assumption that electrons expand their orbits and thereby lower their quantum kinetic energy in the transition to superconductivity. associated with this process, the metal expels negative charge from the interior to the surface and an electric field is generated in the interior. the resulting charge current can be understood as arising from the magnetic lorentz force on radially outgoing electrons, and the resulting spin current can be understood as arising from a spin hall effect originating in the rashba - like coupling of the electron magnetic moment to the internal electric field. the associated electrodynamics is qualitatively different from london electrodynamics, yet can be described by a small modification of the conventional london equations. the stability of the superconducting state and its macroscopic phase coherence hinge on the fact that the orbital angular momentum of the carriers of the spin current is found to be exactly $ \ hbar / 2 $, indicating a topological origin. the simplicity and universality of our theory argue for its validity, and the occurrence of superconductivity in many classes of materials can be understood within our theory.
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arxiv:1106.5311
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free lagrangians are found both for gauge and non - gauge bosonic conformal fields of any symmetry type and in any space - time dimension. conformal gauge fields of various types, their gauge transformations and gauge invariant field strengths ( generalized weyl tensors ), which are derived by the $ \ sigma _ - $ cohomology technics in the frame - like formulation, are shown to correspond to supersymmetric vacua of certain supersymmetric matrix mechanics. the correspondence between conformal and $ ads _ d $ higher - spin models, that turn out to have identical generalized weyl tensors, is discussed.
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arxiv:0909.5226
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