cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The (theta, wheel)-free graphs Part III: cliques, stable sets and coloring
Creators: name: Radovanović, Marko
name: Trotignon, Nicolas
name: Vušković, Kristina
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: A hole in a graph is a chordless cycle of length at least 4. A theta is a graph formed by three paths between the same pair of distinct vertices so that the union of any two of the paths induces a hole. A wheel is a graph formed by a hole and a node that has at least 3 neighbors in the hole. In this series of papers we study the class of graphs that do not contain as an induced subgraph a theta nor a wheel. In Part II of the series we prove a decomposition theorem for this class, that uses clique cutsets and 2-joins, and consequently obtain a polynomial time recognition algorithm for the class. In this paper we further use this decomposition theorem to obtain polynomial time algorithms for maximum weight clique, maximum weight stable set and coloring problems. We also show that for a graph $G$ in the class, if its maximum clique size is $ω$, then its chromatic number is bounded by max$\{ω,3\}$, and that the class is 3-clique-colorable.
Equations for fields with additional fundamental physical constants
Creators: name: Khruschov, V. V.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The author investigates the general Lie algebra of operators of coordinates, momenta, and Lorentz group generators, which can be used in quantum gravity, theories with generalized uncertainty principle, double and triple relativity and theories with noncommutative space-time and momentum spaces. The structure constants of this algebra depend on the constants {\it c} and {\it h}, as well as additional constants with dimensions of action ({\it H}), length ({\it L}), and mass ({\it M}). In the limiting case of infinite {\it H}, {\it L}, and {\it M}, the algebra goes into that of operators of the canonical quantum theory in Minkowski space-time. Some representations of this algebra and equations for generalized fields depending on additional fundamental physical constants are given.
description: 9 pages
Micromechanical modeling approach to derive the yield surface for bcc and fcc steels using statistically informed microstructure models and nonlocal crystal plasticity
Creators: name: Vajragupta Napat
name: Shabaz, Ahmed
name: Boeff Martin
name: Ma, A.
name: Hartmaier Alexander
Publisher: name: Физическая мезомеханика
Year: 2017
Subjects: REPRESENTATIVE VOLUME ELEMENT
VIRTUAL MICROSTRUCTURES
WEIGHTED VORONOI TESSELLATION
NONLOCAL CRYSTAL PLASTICITY FINITE ELEMENT METHOD
BARLATYLD 2004-18P YIELD FUNCTION
ПРЕДСТАВИТЕЛЬНЫЙ ЭЛЕМЕНТ ОБЪЕМА
ВИРТУАЛЬНЫЕ МИКРОСТРУКТУРЫ
ВЗВЕШЕННАЯ ДИАГРАММА ВОРОНОГО
МЕТОД КОНЕЧНЫХ ЭЛЕМЕНТОВ НЕЛОКАЛЬНОЙ ТЕОРИИ ПЛАСТИЧНОСТИ КРИСТАЛЛОВ
ФУНКЦИЯ ТЕКУЧЕСТИ BARLATYLD 2004-18P

description: In order to describe irreversible deformation during metal forming processes, the yield surface is one of the most important criteria. Because of their simplicity and efficiency, analytical yield functions along with experimental guidelines for parameterization become increasingly important for engineering applications. However, the relationship between most of these models and microstructural features are still limited. Hence, we propose to use micromechanical modeling, which considers important microstructural features, as a part of the solution to this missing link. This study aims at the development of a micromechanical modeling strategy to calibrate material parameters for the advanced analytical initial yield function Barlat YLD 2004-18p. To accomplish this, the representative volume element is firstly created based on a method making use of the statistical description of microstructure morphology as input parameter. Such method couples particle simulations to radical Voronoi tessellations to generate realistic virtual microstructures as representative volume elements. Afterwards, a nonlocal crystal plasticity model is applied to describe the plastic deformation of the representative volume element by crystal plasticity finite element simulation. Subsequently, an algorithm to construct the yield surface based on the crystal plasticity finite element simulation is developed. The primary objectives of this proposed algorithm are to automatically capture and extract the yield loci under various loading conditions. Finally, a nonlinear least square optimization is applied to determine the material parameters of Barlat YLD 2004-18p initial yield function of representative volume element, mimicking generic properties of BCC and FCC steels from the numerical simulations.
Coalgebraic Quantum Computation
Creators: name: Roumen, Frank
Publisher: name: arXiv
Year: 2014
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Category Theory (math.CT)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Coalgebras generalize various kinds of dynamical systems occuring in mathematics and computer science. Examples of systems that can be modeled as coalgebras include automata and Markov chains. We will present a coalgebraic representation of systems occuring in the field of quantum computation, using convex sets of density matrices as state spaces. This will allow us to derive a method to convert quantum mechanical systems into simpler probabilistic systems with the same probabilistic behaviour.
description: In Proceedings QPL 2012, arXiv:1407.8427
Integrating Social Media Data and SAR Images for Rapid Urban Flood Inundation Mapping
Creators: name: Shen, Dingtao
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 370403
subject: Geoscience data visualisation
classificationCode: 370402
subject: Earth and space science informatics

description: dataset for paper “Integrating Social Media Data and SAR Images for Rapid Urban Flood Inundation Mapping”
Asymptotics of Robin eigenvalues on sharp infinite cones
Creators: name: Pankrashkin, Konstantin
name: Vogel, Marco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Spectral Theory (math.SP)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35P15, 47A75, 35J05

description: Let $ω\subset\mathbb{R}^n$ be a bounded domain with Lipschitz boundary. For $\varepsilon>0$ and $n\in\mathbb{N}$ consider the infinite cone $Ω_{\varepsilon}:=\big\{(x_1,x')\in (0,\infty)\times\mathbb{R}^n: x'\in\varepsilon x_1ω\big\}\subset\mathbb{R}^{n+1}$ and the operator $Q_{\varepsilon}^α$ acting as the Laplacian $u\mapsto-Δu$ on $Ω_{\varepsilon}$ with the Robin boundary condition $\partial_νu=αu$ at $\partialΩ_\varepsilon$, where $\partial_ν$ is the outward normal derivative and $α>0$. We look at the dependence of the eigenvalues of $Q_\varepsilon^α$ on the parameter $\varepsilon$: this problem was previously addressed for $n=1$ only (in that case, the only admissible $ω$ are finite intervals). In the present work we consider arbitrary dimensions $n\ge2$ and arbitrarily shaped "cross-sections" $ω$ and look at the spectral asymptotics as $\varepsilon$ becomes small, i.e. as the cone becomes "sharp" and collapses to a half-line. It turns out that the main term of the asymptotics of individual eigenvalues is determined by the single geometric quantity $N_ω:=\dfrac{\mathrm{Vol}_{n-1} \partialω}{\mathrm{Vol}_n ω}$. More precisely, for any fixed $j\in \mathbb{N}$ and $α>0$ the $j$th eigenvalue $E_j(Q^α_\varepsilon)$ of $Q^α_\varepsilon$ exists for all sufficiently small $\varepsilon>0$ and satisfies $E_j(Q^α_\varepsilon)=-\dfrac{N_ω^2\,α^2}{(2j+n-2)^2\,\varepsilon^2}+O\left(\dfrac{1}{\varepsilon}\right)$ as $\varepsilon\to 0^+$. The paper also covers some aspects of Sobolev spaces on infinite cones, which can be of independent interest.
description: 31 pages. First Update: The paper is rewritten almost completely. Now it covers arbitrary Lipschitz cross-sections (and not only balls), and more attention is paid to various aspects related to Sobolev spaces. Second Update: Proofs of auxiliary results have been moved to the appendix, for readability purposes. A remark regarding the decay of eigenfunctions has been made at the end of section 4
Euplectrus xanthocephalus Girault
Creators: name: Swezey, O. H.
Publisher: name: Zenodo
Year: 1946
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Aphelinidae
Euplectrus
Euplectrus xanthocephalus

description: 44.Euplectrus (?) xanthocephalus Girault, Queensland Mus., Mem. 2: 273, 1913. Upi Trail, May 5, swept from ferns, Swezey; Machanao, June 4, reared from a caterpillar (Prodenia?) on spiny amaranth, Swezey. Six specimens, three retained in U. S. National Museum.
description: Published as part of Swezey, O. H., 1946, Notes On Some Guam Chalcidoidea, pp. 211-219 in Insects of Guam II, Honolulu, Hawaii :Bernice P. Bishop Museum on page 217, DOI: 10.5281/zenodo.5173516
On the complexity of colouring antiprismatic graphs
Creators: name: Preissmann, Myriam
name: Robin, Cléophée
name: Trotignon, Nicolas
Publisher: name: arXiv
Year: 2019
Subjects: subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: A graph G is prismatic if for every triangle T of G, every vertex of G not in T has a unique neighbour in T. The complement of a prismatic graph is called \emph{antiprismatic}. The complexity of colouring antiprismatic graphs is still unknown. Equivalently, the complexity of the clique cover problem in prismatic graphs is not known. Chudnovsky and Seymour gave a full structural description of prismatic graphs. They showed that the class can be divided into two subclasses: the orientable prismatic graphs, and the non-orientable prismatic graphs. We give a polynomial time algorithm that solves the clique cover problem in every non-orientable prismatic graph. It relies on the the structural description and on later work of Javadi and Hajebi. We give a polynomial time algorithm which solves the vertex-disjoint triangles problem for every prismatic graph. It does not rely on the structural description.
Generalized seniority with realistic interactions in open-shell nuclei
Creators: name: Caprio, M. A.
name: Luo, F. Q.
name: Cai, K.
name: Constantinou, Ch.
name: Hellemans, V.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Generalized seniority provides a truncation scheme for the nuclear shell model, based on pairing correlations, which offers the possibility of dramatically reducing the dimensionality of the nuclear shell-model problem. Systematic comparisons against results obtained in the full shell-model space are required to assess the viability of this scheme. Here, we extend recent generalized seniority calculations for semimagic nuclei, the Ca isotopes, to open-shell nuclei, with both valence protons and valence neutrons. The even-mass Ti and Cr isotopes are treated in a full major shell and with realistic interactions, in the generalized seniority scheme with one broken proton pair and one broken neutron pair. Results for level energies, orbital occupations, and electromagnetic observables are compared with those obtained in the full shell-model space. We demonstrate that, even for the Ti isotopes, significant benefit would be obtained in going beyond the approximation of one broken pair of each type, while the Cr isotopes require further broken pairs to provide even qualitative accuracy.
description: 19 pages, 9 figures; published in J. Phys. G
(Theta, triangle)-free and (even hole, $K_4$)-free graphs. Part 1 : Layered wheels
Creators: name: Sintiari, Ni Luh Dewi
name: Trotignon, Nicolas
Publisher: name: arXiv
Year: 2019
Subjects: subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: We present a construction called layered wheel. Layered wheels are graphs of arbitrarily large treewidth and girth. They might be an outcome for a possible theorem characterizing graphs with large treewidth in terms of their induced subgraphs (while such a characterization is well-understood in terms of minors). They also provide examples of graphs of large treewidth and large rankwidth in well-studied classes, such as (theta, triangle)-free graphs and even-hole-free graphs with no $K_4$ (where a hole is a chordless cycle of length at least four, a theta is a graph made of three internally vertex disjoint paths of length at least two linking two vertices, and $K_4$ is the complete graph on four vertices).
The (theta, wheel)-free graphs Part IV: induced paths and cycles
Creators: name: Radovanović, Marko
name: Trotignon, Nicolas
name: Vušković, Kristina
Publisher: name: arXiv
Year: 2019
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: A hole in a graph is a chordless cycle of length at least 4. A theta is a graph formed by three internally vertex-disjoint paths of length at least 2 between the same pair of distinct vertices. A wheel is a graph formed by a hole and a node that has at least 3 neighbors in the hole. In this series of papers we study the class of graphs that do not contain as an induced subgraph a theta nor a wheel. In Part II of the series we prove a decomposition theorem for this class, that uses clique cutsets and 2-joins. In this paper we use this decomposition theorem to solve several problems related to finding induced paths and cycles in our class.
Fair Presentation
Creators: name: Dosho, Bedasa M.
Publisher: name: Zenodo
Year: 2023

description: Presentation outline CV and Background:  Educational Background  Work Experiences Research project: Heterosis or hybrid vigour Barley Pangenome AIMS Work Plan(WP): WP1 - Production of F1 hybrids using half diallel WP2 - High molecular DNA extraction and sequencing WP2 - High molecular DNA extraction and sequencing WP3 - Testing of hybrid vigour WP4 - Data analysis References
The power of qutrits for non-adaptive measurement-based quantum computing
Creators: name: Mackeprang, Jelena
name: Bhatti, Daniel
name: Hoban, Matty J.
name: Barz, Stefanie
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Non-locality is not only one of the most prominent quantum features but can also serve as a resource for various information-theoretical tasks. Analysing it from an information-theoretical perspective has linked it to applications such as non-adaptive measurement-based quantum computing (NMQC). In this type of quantum computing the goal is to output a multivariate function. The success of such a computation can be related to the violation of a generalised Bell inequality. So far, the investigation of binary NMQC with qubits has shown that quantum correlations can compute all Boolean functions using at most $2^n-1$ qubits, whereas local hidden variables (LHVs) are restricted to linear functions. Here, we extend these results to NMQC with qutrits and prove that quantum correlations enable the computation of all ternary functions using the generalised qutrit Greenberger-Horne-Zeilinger (GHZ) state as a resource and at most $3^n-1$ qutrits. This yields a corresponding generalised GHZ type paradox for any ternary function that LHVs cannot compute. We give an example for an $n$-variate function that can be computed with only $n+1$ qutrits, which leads to convenient generalised qutrit Bell inequalities whose quantum bound is maximal. Finally, we prove that not all functions can be computed efficiently with qutrit NMQC by presenting a counterexample.
Euplectrus sp. near leucostomus Rohwer
Creators: name: Swezey, O. H.
Publisher: name: Zenodo
Year: 1946
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Aphelinidae
Euplectrus

description: 45. Euplectrus sp. near leucostomus Rohwer, Ann. Mag. Nat. Hist., IX, 7: 134, 1921. Machanao, June 30, reared from an unidentified caterpillar on Eugenia, Swezey. Three specimens, one retained in U. S. National Museum.
description: Published as part of Swezey, O. H., 1946, Notes On Some Guam Chalcidoidea, pp. 211-219 in Insects of Guam II, Honolulu, Hawaii :Bernice P. Bishop Museum on page 217, DOI: 10.5281/zenodo.5173516
Constraints on anomalous quartic gauge couplings by $γγ\to W^+W^-$ scattering
Creators: name: Guo, Yu-Chen
name: Wang, Ying-Ying
name: Yang, Ji-Chong
Publisher: name: arXiv
Year: 2019
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The vector boson scattering (VBS) processes in Large Hadron Collider (LHC) experiments offer a unique opportunity to probe the anomalous quartic gauge couplings (aQGCs). We study the dimension-8 operators contributing to the anomalous $γγWW$ coupling and the corresponding unitarity bounds via the exclusive $γγ\to W^+W^-$ production in $pp$ collisions at LHC for a center of mass energy of $\sqrt{s}=13$ TeV. By analysing the kinematical features of the signal, we propose an event selection strategy to highlight the aQGC contributions. Based on the event selection strategy, the statistical significance of the signals are analyzed in detail, and the constraints on the coefficients of the anomalous quartic gauge operators are obtained.
description: 14 pages, 6 figures, 5 tables; References have been updated in the replacement
The expressive power of quantum walks in terms of language acceptance
Creators: name: Barr, Katie
name: Kendon, Viv
Publisher: name: arXiv
Year: 2014
Subjects: subject: Formal Languages and Automata Theory (cs.FL)
subject: Emerging Technologies (cs.ET)
subject: Quantum Physics (quant-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Discrete time quantum walks are known to be universal for quantum computation. This has been proven by showing that they can simulate a universal quantum gate set. In this paper, we examine computation by quantum walks in terms of language acceptance, and present two ways in which discrete time quantum walks can accept some languages with certainty. These walks can take quantum as well as classical inputs, and we show that when the input is quantum, the walks can also be interpreted as performing the task of quantum state discrimination.
description: In Proceedings QPL 2012, arXiv:1407.8427
Towards Escaping from Language Bias and OCR Error: Semantics-Centered Text Visual Question Answering
Creators: name: Fang, Chengyang
name: Zeng, Gangyan
name: Zhou, Yu
name: Wu, Daiqing
name: Ma, Can
name: Hu, Dayong
name: Wang, Weiping
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Multimedia (cs.MM)
subject: FOS: Computer and information sciences

description: Texts in scene images convey critical information for scene understanding and reasoning. The abilities of reading and reasoning matter for the model in the text-based visual question answering (TextVQA) process. However, current TextVQA models do not center on the text and suffer from several limitations. The model is easily dominated by language biases and optical character recognition (OCR) errors due to the absence of semantic guidance in the answer prediction process. In this paper, we propose a novel Semantics-Centered Network (SC-Net) that consists of an instance-level contrastive semantic prediction module (ICSP) and a semantics-centered transformer module (SCT). Equipped with the two modules, the semantics-centered model can resist the language biases and the accumulated errors from OCR. Extensive experiments on TextVQA and ST-VQA datasets show the effectiveness of our model. SC-Net surpasses previous works with a noticeable margin and is more reasonable for the TextVQA task.
(Theta, triangle)-free and (even hole, $K_4$)-free graphs. Part 2 : bounds on treewidth
Creators: name: Pilipczuk, Marcin
name: Sintiari, Ni Luh Dewi
name: Thomassé, Stéphan
name: Trotignon, Nicolas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: A {\em theta} is a graph made of three internally vertex-disjoint chordless paths $P_1 = a \dots b$, $P_2 = a \dots b$, $P_3 = a \dots b$ of length at least~2 and such that no edges exist between the paths except the three edges incident to $a$ and the three edges incident to $b$. A {\em pyramid} is a graph made of three chordless paths $P_1 = a \dots b_1$, $P_2 = a \dots b_2$, $P_3 = a \dots b_3$ of length at least~1, two of which have length at least 2, vertex-disjoint except at $a$, and such that $b_1b_2b_3$ is a triangle and no edges exist between the paths except those of the triangle and the three edges incident to~$a$. An \emph{even hole} is a chordless cycle of even length. For three non-negative integers $i\leq j\leq k$, let $S_{i,j,k}$ be the tree with a vertex $v$, from which start three paths with $i$, $j$, and $k$ edges respectively. We denote by $K_t$ the complete graph on $t$ vertices. We prove that for all non-negative integers $i, j, k$, the class of graphs that contain no theta, no $K_3$, and no $S_{i, j, k}$ as induced subgraphs have bounded treewidth. We prove that for all non-negative integers $i, j, k, t$, the class of graphs that contain no even hole, no pyramid, no $K_t$, and no $S_{i, j, k}$ as induced subgraphs have bounded treewidth. To bound the treewidth, we prove that every graph of large treewidth must contain a large clique or a minimal separator of large cardinality.
Analytical evaluation of atomic form factors: application to Rayleigh scattering
Creators: name: Safari, L.
name: Santos, J. P.
name: Amaro, P.
name: Jänkälä, K.
name: Fratini, F.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Atomic form factors are widely used for the characterization of targets and specimens, from crystallography to biology. By using recent mathematical results, here we derive an analytical expression for the atomic form factor within the independent particle model constructed from nonrelativistic screened hydrogenic wavefunctions. The range of validity of this analytical expression is checked by comparing the analytically obtained form factors with the ones obtained within the Hartee-Fock method. As an example, we apply our analytical expression for the atomic form factor to evaluate the differential cross section for Rayleigh scattering off neutral atoms.
description: 7 pages, 1 figure
NL-FCOS: Improving FCOS through Non-Local Modules for Object Detection
Creators: name: Pavez, Lukas
name: Rondo, Jose M. Saavedra
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: During the last years, we have seen significant advances in the object detection task, mainly due to the outperforming results of convolutional neural networks. In this vein, anchor-based models have achieved the best results. However, these models require prior information about the aspect and scales of target objects, needing more hyperparameters to fit. In addition, using anchors to fit bounding boxes seems far from how our visual system does the same visual task. Instead, our visual system uses the interactions of different scene parts to semantically identify objects, called perceptual grouping. An object detection methodology closer to the natural model is anchor-free detection, where models like FCOS or Centernet have shown competitive results, but these have not yet exploited the concept of perceptual grouping. Therefore, to increase the effectiveness of anchor-free models keeping the inference time low, we propose to add non-local attention (NL modules) modules to boost the feature map of the underlying backbone. NL modules implement the perceptual grouping mechanism, allowing receptive fields to cooperate in visual representation learning. We show that non-local modules combined with an FCOS head (NL-FCOS) are practical and efficient. Thus, we establish state-of-the-art performance in clothing detection and handwritten amount recognition problems.
Locating the critical end point of QCD
Creators: name: Fischer, Christian S.
name: Luecker, Jan
name: Welzbacher, Christian A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We summarize recent results for the phase structure of QCD at finite temperature and light-quark chemical potential for N_f=2+1 and N_f=2+1+1 dynamical quark flavors. We discuss order parameters for the chiral and deconfinement transitions obtained from solutions of a coupled set of (truncated) Dyson-Schwinger equations for the quark and gluon propagators of Landau gauge QCD. Based on excellent agreement with results from lattice-QCD at zero chemical potential we study the possible appearance of a critical end-point at large chemical potential.
description: Proceedings for Quark Matter 2014, Darmstadt (Germany), May 19-24, 2014
Speakable in quantum mechanics: babbling on
Creators: name: Hermens, Ronnie
Publisher: name: arXiv
Year: 2014
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Quantum Physics (quant-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: This paper consists of a short version of the derivation of the intuitionistic quantum logic L_QM (which was originally introduced by Caspers, Heunen, Landsman and Spitters). The elaboration consists of extending this logic to a classical logic CL_QM. Some first steps are then taken towards setting up a probabilistic framework based on CL_QM in terms of Rényi's conditional probability spaces. Comparisons are then made with the traditional framework for quantum probabilities.
description: In Proceedings QPL 2012, arXiv:1407.8427
Effective and Robust Detection of Adversarial Examples via Benford-Fourier Coefficients
Creators: name: Ma, Chengcheng
name: Wu, Baoyuan
name: Xu, Shibiao
name: Fan, Yanbo
name: Zhang, Yong
name: Zhang, Xiaopeng
name: Li, Zhifeng
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Adversarial examples have been well known as a serious threat to deep neural networks (DNNs). In this work, we study the detection of adversarial examples, based on the assumption that the output and internal responses of one DNN model for both adversarial and benign examples follow the generalized Gaussian distribution (GGD), but with different parameters (i.e., shape factor, mean, and variance). GGD is a general distribution family to cover many popular distributions (e.g., Laplacian, Gaussian, or uniform). It is more likely to approximate the intrinsic distributions of internal responses than any specific distribution. Besides, since the shape factor is more robust to different databases rather than the other two parameters, we propose to construct discriminative features via the shape factor for adversarial detection, employing the magnitude of Benford-Fourier coefficients (MBF), which can be easily estimated using responses. Finally, a support vector machine is trained as the adversarial detector through leveraging the MBF features. Extensive experiments in terms of image classification demonstrate that the proposed detector is much more effective and robust on detecting adversarial examples of different crafting methods and different sources, compared to state-of-the-art adversarial detection methods.
description: Machine Intelligence Research, 2022
The classification of smooth well-formed Fano weighted complete intersections
Creators: name: Ovcharenko, Mikhail
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14J45

description: We show that the set of families of smooth well-formed Fano weighted complete intersections admits a natural partition with respect to the variance $\mathrm{var}(X) = \mathrm{coind}(X) - \mathrm{codim}(X)$. Moreover, we obtain the classification of smooth well-formed Fano weighted complete intersections of small variance. We also prove that the anticanonical linear system on a smooth well-formed Fano weighted complete intersection of anticanonical degree one is never base-point free.
description: 26 pages. A small fix in Example 1.10 and Remark 1.11
The connection between regular black holes in nonlinear electrodynamics and semi-classical dust collapse
Creators: name: Malafarina, Daniele
name: Toshmatov, Bobir
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: There exist a correspondence between black holes in non linear electrodynamics (NLED) and gravitational collapse of homogeneous dust with semi-classical corrections in the strong curvature regime that to our knowledge has not been noticed until now. We discuss the nature of such correspondence and explore what insights may be gained from considering black holes in NLED in the context of semi-classical dust collapse and vice-versa.
description: 4 pages, 2 figures
Tropical Monte Carlo quadrature for Feynman integrals
Creators: name: Borinsky, Michael
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mathematical Physics (math-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Algebraic Geometry (math.AG)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 81Q30 (Primary) 14E15, 14T90 (Secondary)

description: We introduce a new method to evaluate algebraic integrals over the simplex numerically. This new approach employs techniques from tropical geometry and exceeds the capabilities of existing numerical methods by an order of magnitude. The method can be improved further by exploiting the geometric structure of the underlying integrand. As an illustration of this, we give a specialized integration algorithm for a class of integrands that exhibit the form of a generalized permutahedron. This class includes integrands for scattering amplitudes and parametric Feynman integrals with tame kinematics. A proof-of-concept implementation is provided with which Feynman integrals up to loop order 17 can be evaluated.
description: 6 figures, see http://github.com/michibo/tropical-feynman-quadrature for the referenced program code; v2: typos corrected, version accepted for publication in Annales de l'Institut Henri Poincar\'e D
A class of graphs with large rankwidth
Creators: name: Hoàng, Chính
name: Trotignon, Nicolas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics
subject: G.2.2
subject: 05C85

description: We describe several graphs with arbitrarily large rankwidth (or equivalently with arbitrarily large cliquewidth). Korpelainen, Lozin, and Mayhill [Split permutation graphs, Graphs and Combinatorics, 30(3):633-646, 2014] proved that there exist split graphs with Dilworth number 2 with arbitrarily large rankwidth, but without explicitly constructing them. We provide an explicit construction. Maffray, Penev, and Vušković [Coloring rings, Journal of Graph Theory 96(4):642-683, 2021] proved that graphs that they call rings on $n$ sets can be colored in polynomial time. We show that for every fixed integer $n\geq 3$, there exist rings on $n$ sets with arbitrarily large rankwidth. When $n\geq 5$ and $n$ is odd, this provides a new construction of even-hole-free graphs with arbitrarily large rankwidth.
A stopping criterion for iterative proton CT image reconstruction based on correlated noise properties
Creators: name: DeJongh, Ethan A.
name: Pryanichnikov, Alexander A.
name: DeJongh, Don F.
name: Schulte, Reinhard W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Background: Whereas filtered back projection algorithms for voxel-based CT image reconstruction have noise properties defined by the filter, iterative algorithms must stop at some point in their convergence and do not necessarily produce consistent noise properties for images with different degrees of heterogeneity. Purpose: A least-squares iterative algorithm for pCT image reconstruction converges toward a unique solution for RSP that optimally fits the protons. We present a stopping criterion that delivers solutions with the property that correlations of RSP noise between voxels are relatively low. This provides a method to produce pCT images with consistent noise properties useful for proton therapy treatment planning, which relies on summing RSP along lines of voxels. Methods: With simulated and real images with varying heterogeneity from a prototype clinical proton imaging system, we calculate average RSP correlations between voxel pairs in uniform regions-of-interest versus distance between voxels. We define a parameter r, the remaining distance to the unique solution relative to estimated RSP noise, and our stopping criterion is based on r falling below a chosen value. Results: We find large correlations between voxels for larger values of r, and anticorrelations for smaller values. For r in the range of 0.5 to 1, voxels are relatively uncorrelated, and compared to smaller values of r have lower noise with only slight loss of spatial resolution. Conclusions: Iterative algorithms not using a specific metric or rationale for stopping iterations may produce images with an unknown and arbitrary level of convergence or smoothing. We resolve this issue by stopping iterations when r reaches the range of 0.5 to 1. This defines a pCT image reconstruction method with consistent statistical properties optimal for clinical use, including for treatment planning with pCT images.
description: Accepted for publication in Journal of Applied Clinical Medical Physics
Łojasiewicz-Simon inequalities for minimal networks: stability and convergence
Creators: name: Pluda, Alessandra
name: Pozzetta, Marco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Differential Geometry (math.DG)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We investigate stability properties of the motion by curvature of planar networks. We prove Lojasiewicz-Simon gradient inequalities for the length functional of planar networks with triple junctions. In particular, such an inequality holds for networks with junctions forming angles equal to $\tfrac23π$ that are close in $H^2$-norm to minimal networks, i.e., networks whose edges also have vanishing curvature. The latter inequality bounds a concave power of the difference between length of a minimal network $Γ_*$ and length of a triple junctions network $Γ$ from above by the $L^2$-norm of the curvature of the edges of $Γ$. We apply this result to prove the stability of minimal networks in the sense that a motion by curvature starting from a network sufficiently close in $H^2$-norm to a minimal one exists for all times and smoothly converges. We further rigorously construct an example of a motion by curvature having uniformly bounded curvature that smoothly converges to a degenerate network in infinite time.
Cubic fourfolds, Kuznetsov components and Chow motives
Creators: name: Fu, Lie
name: Vial, Charles
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We prove that the Chow motives of two smooth cubic fourfolds whose Kuznetsov components are Fourier-Mukai derived-equivalent are isomorphic as Frobenius algebra objects. As a corollary, we obtain that there exists a Galois-equivariant isomorphism between their l-adic cohomology Frobenius algebras. We also discuss the case where the Kuznetsov component of a smooth cubic fourfold is Fourier-Mukai derived-equivalent to a K3 surface.
description: 22 pages
Tetrastichus hagenowii
Creators: name: Swezey, O. H.
Publisher: name: Zenodo
Year: 1946
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Aphelinidae
Tetrastichus
Tetrastichus hagenowii

description: 46.Tetrastichus hagenowii (Ratzeburg). Entedon hagenowii Ratzeburg, Ichneumon. der Forstins. 3: 211, 1852. Merizo, Oct. 2, one specimen, Swezey. Bishop Museum has 13 specimens, collected by Fullaway in 1911.
description: Published as part of Swezey, O. H., 1946, Notes On Some Guam Chalcidoidea, pp. 211-219 in Insects of Guam II, Honolulu, Hawaii :Bernice P. Bishop Museum on page 217, DOI: 10.5281/zenodo.5173516
Purcell effect of nitrogen-vacancy centers in nanodiamond coupled to propagating and localized surface plasmons revealed by photon-correlation cathodoluminescence
Creators: name: Yanagimoto, Sotatsu
name: Yamamoto, Naoki
name: Sannomiya, Takumi
name: Akiba, Keiichirou
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We measured the second-order correlation function of the cathodoluminescence intensity and investigated the Purcell effect by comparing the lifetimes of quantum emitters with and without metal structure. The increase in the electromagnetic local density of state due to the coupling of a quantum emitter with a plasmonic structure causes a shortening of the emitter lifetime, which is called the Purcell effect. Since the plasmon-enhanced electric field is confined well below the wavelength of light, the quantum emitter lifetime is changed in the nanoscale range. In this study, we combined cathodoluminescence in scanning (transmission) electron microscopy with Hanbury Brown-Twiss interferometry to measure the Purcell effect with nanometer and nanosecond resolutions. We used nitrogen-vacancy centers contained in nanodiamonds as quantum emitters and compared their lifetime in different environments: on a thin SiO2 membrane, on a thick flat silver film, and embedded in a silver film. The lifetime reductions of nitrogen-vacancy centers were clearly observed in the samples with silver. We evaluated the lifetime by analytical calculation and numerical simulations and revealed the Purcell effects of emitters coupled to propagating and localized surface plasmons. This is the first experimental result showing the Purcell effect due to the coupling between nitrogen-vacancy centers in nanodiamonds and surface plasmon polaritons with nanometer resolution.
Red Alarm for Pre-trained Models: Universal Vulnerability to Neuron-Level Backdoor Attacks
Creators: name: Zhang, Zhengyan
name: Xiao, Guangxuan
name: Li, Yongwei
name: Lv, Tian
name: Qi, Fanchao
name: Liu, Zhiyuan
name: Wang, Yasheng
name: Jiang, Xin
name: Sun, Maosong
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Pre-trained models (PTMs) have been widely used in various downstream tasks. The parameters of PTMs are distributed on the Internet and may suffer backdoor attacks. In this work, we demonstrate the universal vulnerability of PTMs, where fine-tuned PTMs can be easily controlled by backdoor attacks in arbitrary downstream tasks. Specifically, attackers can add a simple pre-training task, which restricts the output representations of trigger instances to pre-defined vectors, namely neuron-level backdoor attack (NeuBA). If the backdoor functionality is not eliminated during fine-tuning, the triggers can make the fine-tuned model predict fixed labels by pre-defined vectors. In the experiments of both natural language processing (NLP) and computer vision (CV), we show that NeuBA absolutely controls the predictions for trigger instances without any knowledge of downstream tasks. Finally, we apply several defense methods to NeuBA and find that model pruning is a promising direction to resist NeuBA by excluding backdoored neurons. Our findings sound a red alarm for the wide use of PTMs. Our source code and models are available at \url{https://github.com/thunlp/NeuBA}.
description: Published in Machine Intelligence Research (https://link.springer.com/article/10.1007/s11633-022-1377-5)
Between quantum logic and concurrency
Creators: name: Bernardinello, Luca
name: Ferigato, Carlo
name: Pomello, Lucia
Publisher: name: arXiv
Year: 2014
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Computer and information sciences

description: We start from two closure operators defined on the elements of a special kind of partially ordered sets, called causal nets. Causal nets are used to model histories of concurrent processes, recording occurrences of local states and of events. If every maximal chain (line) of such a partially ordered set meets every maximal antichain (cut), then the two closure operators coincide, and generate a complete orthomodular lattice. In this paper we recall that, for any closed set in this lattice, every line meets either it or its orthocomplement in the lattice, and show that to any line, a two-valued state on the lattice can be associated. Starting from this result, we delineate a logical language whose formulas are interpreted over closed sets of a causal net, where every line induces an assignment of truth values to formulas. The resulting logic is non-classical; we show that maximal antichains in a causal net are associated to Boolean (hence "classical") substructures of the overall quantum logic.
description: In Proceedings QPL 2012, arXiv:1407.8427
Exact Noncommutative Two-Dimensional Hydrogen Atom
Creators: name: Wang, Beatriz
name: Brenag, Emanuel
name: Amorim, Ronni
name: Rispoli, Vinicius
name: Ulhoa, Sergio
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this work, we present an exact analysis of two-dimensional noncommutative hydrogen atom. In this study, it is used the Levi-Civita transformation to perform the solution of the noncommutative Schrödinger equation for Coulomb potential. As an important result, we determine the energy levels for the considered system. Using the result obtained and experimental data, a bound on the noncommutativity parameter was obtained.
description: 9 pages, no figures
The Noncommutative Coulomb Potential
Creators: name: Wang, Beatriz
name: Brenag, Emanuel
name: Amorim, Ronni
name: Rispoli, Vinicius
name: Ulhoa, Sergio
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this work, we analyze the noncommutative three-dimensional Coulomb potential problem. For this purpose, we used the Kustaanheimo-Stiefel mapping to write the Schrödinger equation for Coulomb potential in a solvable way. Then, the noncommutative hydrogen-like atoms were treated, and their energy levels were found. In addition, we estimate a bound for the noncommutativity parameter.
The study of neutral triple gauge couplings in the process $e^+e^-\to Zγ$ including unitarity bounds
Creators: name: Fu, Qing
name: Yang, Ji-Chong
name: Yue, Chong-Xing
name: Guo, Yu-Chen
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The neutral triple gauge couplings~(nTGCs) provide a unique opportunity to probe new physics beyond the Standard Model. The nTGCs can be described by an effective field theory~(EFT), which is valid only under a certain energy scale. One of the signatures that an EFT is no longer valid is the violation of unitarity. We study the partial wave unitarity bounds on the coefficients of nTGCs in the process $e^+e^-\to Zγ$. In the experiments, the constraints obtained should be tighter than the unitarity bounds, otherwise the results are meaningless, therefore there exists a minimal luminosity for a $e^+e^-$ collider such as the CEPC to study the nTGCs. To derive the minimal luminosity, the kinematic features and event selection strategy are studied by Monte-Carlo simulation. Both the processes $e^+e^-\to \ell^+\ell^-γ$ and $e^+e^-\to jjγ$ are studied, event selection strategies are discussed. Based on the statistical significance, the expected constraints in experiments are estimated. The required luminosities for the experiments to reach the unitarity bounds are presented.
description: 20 pages, 10 figures
Confined Neutrino Oscillation
Creators: name: Chakraborty, Pralay
name: Roy, Subhankar
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: A thought experiment is designed to speculate on the neutrino being trapped in an impenetrable potential well. Considering both relativistic and non-relativistic scenarios, we delve into several interesting facets connected to the flavour oscillation.
Effect of vacuum arc ion beam treatment on the structure and mechanical properties of steel 30crmnsini2а
Creators: name: Panin, S.V.
name: Vlasov, I.V.
name: Sergeev, V.P.
name: Ovechkin, B.B.
name: Lyubutin, P.S.
name: Sunder Ramasubbu
name: Mironov Yu.P.
name: Marushchak, P.O.
Publisher: name: Физическая мезомеханика
Year: 2015
Subjects: УСТАЛОСТНАЯ ДОЛГОВЕЧНОСТЬ
FATIGUE LIFE
ИОННО-ЛУЧЕВАЯ ОБРАБОТКА
ДЕФОРМАЦИЯ
DEFORMATION
РАЗРУШЕНИЕ
FRACTURE
ION BEAM TREATMENT

description: The surface layer and cross section structure of high-strength steel 30CrMnSiNi2А specimens of thickness 1 mm modified by ion beam treatment is studied using optical, transmission, scanning electron microscopy, and X-ray diffraction. Static and cyclic tensile tests are conducted for the specimens prior to and after Zr + ion beam irradiation; this modification technique is shown to increase the fatigue life of the material. Differences in the deformation behavior of the specimens and variation of their mechanical properties are analyzed. The causes of the increase in the fatigue life of the irradiated specimens are discussed in view of the structural changes revealed.
Detecting Topological Currents in Graphene Superlattices
Creators: name: Gorbachev, R. V.
name: Song, J. C. W.
name: Yu, G. L.
name: Kretinin, A. V.
name: Withers, F.
name: Cao, Y.
name: Mishchenko, A.
name: Grigorieva, I. V.
name: Novoselov, K. S.
name: Levitov, L. S.
name: Geim, A. K.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Topological materials may exhibit Hall-like currents flowing transversely to the applied electric field even in the absence of a magnetic field. In graphene superlattices, which have broken inversion symmetry, topological currents originating from graphene's two valleys are predicted to flow in opposite directions and combine to produce long-range charge neutral flow. We observe this effect as a nonlocal voltage at zero magnetic field in a narrow energy range near Dirac points at distances as large as several microns away from the nominal current path. Locally, topological currents are comparable in strength to the applied current, indicating large valley-Hall angles. The long-range character of topological currents and their transistor-like control by gate voltage can be exploited for information processing based on the valley degrees of freedom.
description: 19 pgs, 9 fgs