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SURVEY OF ACTION RECOGNITION, SPOTTING AND SPATIO-TEMPORAL LOCALIZATION IN SOCCER - CURRENT TRENDS AND RESEARCH PERSPECTIVES

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arXiv 2023年

作者： Seweryn, Karolina Wróblewska, Anna Lukasik, Szymon NASK - National Research Institute Warsaw Poland Faculty of Mathematics and Information Science Warsaw University of Technology Warsaw Poland Faculty of Physics and Applied Computer Science AGH University of Science and Technology Cracow Poland

Action scene understanding in soccer is a challenging task due to the complex and dynamic nature of the game, as well as the interactions between players. This article provides a comprehensive overview of this task divided into action recognition, spotting, and spatio-temporal action localization, with a particular emphasis on the modalities used and multimodal methods. We explore the publicly available data sources and metrics used to evaluate models' performance. The article reviews recent state-of-the-art methods that leverage deep learning techniques and traditional methods. We focus on multimodal methods, which integrate information from multiple sources, such as video and audio data, and also those that represent one source in various ways. The advantages and limitations of methods are discussed, along with their potential for improving the accuracy and robustness of models. Finally, the article highlights some of the open research questions and future directions in the field of soccer action recognition, including the potential for multimodal methods to advance this field. Overall, this survey provides a valuable resource for researchers interested in the field of action scene understanding in soccer. © 2023, CC BY.

关键词： Deep learning

Phase-field simulations of the effect of temperature and interface for zirconium δ-hydrides

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arXiv 2023年

作者： Chen, Zi-Hang Sheng, Jie Liu, Yu Shi, Xiao-Ming Huang, Houbing Xu, Ke Wang, Yue-Chao Wu, Shuai Sun, Bo Liu, Hai-Feng Song, Hai-Feng School of Materials Science and Engineering Beijing Institute of Technology Beijing100081 China Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing100081 China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China Department of Physics University of Science and Technology Beijing Beijing100083 China

Hydride precipitation in zirconium cladding materials can damage their integrity and durability. Service temperature and material defects have a significant effect on the dynamic growth of hydrides. In this study, we have developed a phase field model based on the assumption of elastic behaviour within a specific temperature range (613-653K). This model allows us to study the influence of temperature and interfacial effects on the morphology, stress, and average growth rate of zirconium hydride. The results suggest that changes in temperature and interfacial energy influence the aspect ratio and average growth rate of the hydride morphology. The ultimate determinant of hydride orientation is the loss of interfacial coherence, primarily induced by interfacial dislocation defects and quantifiable by the mismatch degree q. An escalation in interfacial coherence loss leads to a transition of hydride growth from horizontal to vertical, accompanied by the onset of redirection behaviour. Interestingly, redirection occurs at a critical mismatch level, denoted qc, and remains unaffected by variations in temperature and interfacial energy. However, this redirection leads to an increase in the maximum stress, which may influence the direction of hydride crack propagation. This research highlights the importance of interfacial coherence and provides valuable insights into the morphology and growth kinetics of hydrides in zirconium alloys. Copyright © 2023, The Authors. All rights reserved.

关键词： Hydrides

Toward a comprehensive hypothesis of oxygen-evolution reaction in the presence of iron and gold

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Journal of Energy Chemistry 2024年第2期89卷 172-183,I0005页

作者： Negah Hashemi Jafar Hussain Shah Cejun Hu Subhajit Nandy Pavlo Aleshkevych Sumbal Farid Keun Hwa Chae Wei Xie Taifeng Liu Junhu Wang Mohammad Mahdi Najafpour Department of Chemistry Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Center for Advanced Mössbauer Spectroscopy Mössbauer Effect Data CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Lab of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China Advanced Analysis Center Korea Institute of Science and TechnologySeoul 02792Republic of Korea Institute of Physics Polish Academy of SciencesWarsaw 02-668Poland National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina Center of Climate Change and Global Warming Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research Center for Basic Sciences&Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran

This study investigates the effects of Fe on the oxygen-evolution reaction(OER)in the presence of *** distinct areas of OER were identified:the first associated with Fe sites at low overpotential(~330 mV),and the second with Au sites at high overpotential(~870 mV).Various factors such as surface Fe concentration,electrochemical method,scan rate,potential range,concentration,method of adding K_(2)Fe O_(4),nature of Fe,and temperature were varied to observe diverse behaviors during OER for Fe O_(x)H_(y)/*** amounts of Fe ions had a significant impact on OER,reaching a saturation point where the activity did not increase *** electronic interaction between Fe and Au ions was indicated by X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)*** situ visible spectroscopy confirmed the formation of Fe O_(4)^(2-)during *** situ Mossbauer and surfaceenhanced Raman spectroscopy(SERS)analyses suggest the involvement of Fe-based species as intermediates during the rate-determining step of OER.A lattice OER mechanism based on Fe O_(x)H_(y)was proposed for operation at low *** functional theory(DFT)calculations revealed that Fe oxide,Fe-oxide clusters,and Fe doping on the Au foil exhibited different activities and stabilities during *** study provides insights into the interplay between Fe and Au in OER,advancing the understanding of OER mechanisms and offering implications for the design of efficient electrocatalytic systems.

关键词： DFT calculation Fe/Au electrocatalysis Mechanism Oxygen evolution Water oxidation

Asymptotic Stability of the Equilibrium for the Free Boundary Problem of a Compressible Atmospheric Primitive Model with Physical Vacuum

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SSRN

SSRN 2025年

作者： Liu, Xin Titi, Edriss S. Xin, Zhouping Department of Mathematics Texas A&M University College StationTX77843-3368 United States Department of Mathematics Texas A&M University College StationTX77843-3368 United States Department of Applied Mathematics and Theoretical Physics University of Cambridge CambridgeCB3 0WA United Kingdom Department of Computer Science and Applied Mathematics Weizmann Institute of Science Rehovot76100 Israel The Institute of Mathematical Sciences The Chinese University of Hong Kong New Territories Shatin Hong Kong

This paper concerns the large time asymptotic behavior of solutions to the free boundary problem of the compressible primitive equations in atmospheric dynamics with physical vacuum. We have introduced a model of the compressible primitive equations with a specific viscosity and shown that the physical vacuum free boundary problem for this model system has a global-in-time solution converging to an equilibrium exponentially, provided that the initial data is a small perturbation of the equilibrium. More precisely, we introduce a new coordinate system by choosing the enthalpy (the square of sound speed) as the vertical coordinate, and thanks to the hydrostatic balance, the degenerate density at the free boundary admits a representation with separation of variables in the new coordinates. Such a property allows us to establish horizontal derivative estimates without involving the singular vertical derivative of the density profile, which plays a key role in our analysis. © 2025, The Authors. All rights reserved.

关键词： Viscosity

Characterizing the negative triangularity reactor core operating space with integrated modeling

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arXiv 2024年

作者： Wilson, H.S. Nelson, A.O. McClenaghan, J. Rodriguez-Fernandez, P. Parisi, J. Paz-Soldan, C. Department of Applied Physics and Applied Mathematics Columbia University New YorkNY10027 United States General Atomics San DiegoCA92121 United States Plasma Science and Fusion Center Massachusetts Institute of Technology CambridgeMA02139 United States Princeton Plasma Physics Laboratory PrincetonNJ08540 United States

Negative triangularity (NT) has received renewed interest as a fusion reactor regime due to its beneficial power-handling properties, including low scrape-off layer power and a larger divertor wetted area that facilitates simple divertor integration. NT experiments have also demonstrated core performance on par with positive triangularity (PT) H-mode without edge-localized modes (ELMs), encouraging further study of an NT reactor core. In this work, we use integrated modeling to scope the operating space around two NT reactor strategies. The first is the high-field, compact fusion pilot plant concept MANTA (The MANTA Collaboration et al 2024 Plasma Phys. Control. Fusion 66 105006) and the second is a low field, high aspect ratio concept based on work by Medvedev et al (Medvedev et al 2015 Nucl. Fusion 55 063013). By integrating equilibrium, core transport, and edge ballooning instability models, we establish a range of operating points with less than 50 MW scrape-off layer power and fusion power comparable to positive triangularity (PT) H-mode reactor concepts. Heating and seeded impurities are leveraged to accomplish the same fusion performance and scrape-off layer exhaust power for various pressure edge boundary conditions. Scans over these pressure edge conditions accommodate any current uncertainty of the properties of the NT edge and show that the performance of an NT reactor will be extremely dependent on the edge pressure. The high-field case is found to enable lower scrape-off layer power because it is capable of reaching high fusion powers at a relatively compact size, which allows increased separatrix density without exceeding the Greenwald density limit. Adjustments in NT shaping exhibit small changes in fusion power, with an increase in fusion power density seen at weaker NT. Infinite-n ballooning instability models indicate that an NT reactor core can reach fusion powers comparable to leading PT H-mode reactor concepts while remaining ballooning-stable.

关键词： Aspect ratio

Current and further trajectories in designing functional materials for solid oxide electrochemical cells:A review of other reviews

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Journal of Energy Chemistry 2024年第7期94卷 302-331页

作者： Stanislav Baratov Elena Filonova Anastasiya Ivanova Muhammad Bilal Hanif Muneeb Irshad Muhammad Zubair Khan Martin Motola Sajid Rauf Dmitry Medvedev Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia Institute of Natural Sciences and Mathematics Ural Federal University620002 EkaterinburgRussia Department of Inorganic Chemistry Faculty of Natural SciencesComenius University BratislavaIlkovicova 6Mlynska Dolina84215 BratislavaSlovakia State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049ShaanxiChina Department of Physics University of Engineering and TechnologyLahore 54890Pakistan Pak-Austria Fachhochschule:Institute of Applied Sciences and Technology Mang Haripur 22621Khyber PakhtunkhwaPakistan College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518000GuangdongChina Laboratory of Electrochemical Devices Based on Solid Oxide Proton Electrolytes Institute of High Temperature Electrochemistry620066 EkaterinburgRussia

Complex oxides are an important class of materials with enormous potential for electrochemical *** on their composition and structure,such complex oxides can exhibit either a single conductivity(oxygen-ionic or protonic,or n-type,or p-type electronic)or a combination thereof gener-ating distinct dual-conducting or even triple-conducting *** properties enable their use as diverse functional materials for solid oxide fuel cells,solid oxide electrolysis cells,permeable membranes,and gas *** literature review shows that the field of solid oxide materials and related electro-chemical cells has a significant level of research engagement,with over 8,000 publications published since *** manual analysis of such a large volume of material is ***,by examining the review articles,it is possible to identify key patterns,recent achievements,prospects,and remaining *** perform such an analysis,the present article provides,for the first time,a comprehensive summary of previous review publications that have been published since 2020,with a special focus on solid oxide materials and electrochemical ***,this study provides an important reference for researchers specializing in the fields of solid state ionics,high-temperature electrochemistry,and energyconversiontechnologies.

关键词： SOFCs SOECs PCFCS Electrochemistry Energy conversion Hydrogen energy,Carbon neutrality

Shock Wave Structure of One-Dimensional Hydro-Elastoplastic Riemann Problem with Elastic-Plastic-Fluid Phase Transition

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SSRN

SSRN 2023年

作者： Li, Xiao Shen, Zhijun Zhang, Hongping College of Big Data and Internet Shenzhen Technology University Guangdong Shenzhen518118 China Institute of Applied Physics and Computational Mathematics LCP P. O. Box 8009-26 Beijing100088 China HEDPS Center for Applied Physics and Technology College of Engineering Peking University Beijing100871 China

In this work, the types of shock wave structure for hydro-elastoplastic model under compression are researched. The emphasis focuses on the theory of shock transition in the presence of elastic-plastic-fluid phase transition. As a result, in addition to the classical three-wave structure, two new shock wave patterns are found with the increase of loading strength. Several numerical tests are presented to verify the existence of the three types of wave structure. © 2023, The Authors. All rights reserved.

关键词： Shock waves

On the Ternary Ohta-Kawasaki Free Energy and Its One-dimensional Global Minimizers

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arXiv 2021年

作者： Xu, Zirui Du, Qiang Department of Applied Physics and Applied Mathematics Columbia University New YorkNY10027 United States Department of Applied Physics and Applied Mathematics Data Science Institute Columbia University New YorkNY10027 United States

We study the ternary Ohta-Kawasaki free energy that has been used to model triblock copolymer systems. Its one-dimensional global minimizers are conjectured to have cyclic patterns. However, some physical experiments and computer simulations found triblock copolymers forming noncyclic lamellar patterns. In this work, by comparing the free energies of the cyclic pattern and some noncyclic candidates, we show that the conjecture does not hold for some choices of parameters. Our results suggest that even in one dimension, the global minimizers may take on very different patterns in different parameter regimes. To unify the existing choices of the long range coefficient matrix, we present a reformulation of the long range term using a generalized charge interpretation, and thereby propose conditions on the matrix in order for the global minimizers to reproduce physically relevant nanostructures of block *** Codes 49N99 Copyright © 2021, The Authors. All rights reserved.

关键词： Free energy

Macroscopic auxiliary asymptotic preserving neural networks for the linear radiative transfer equations

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arXiv 2024年

作者： Li, Hongyan Jiang, Song Sun, Wenjun Xu, Liwei Zhou, Guanyu School of Mathematical Sciences University of Electronic Science and Technology of China Sichuan Chengdu611731 China Institute of Applied Physics and Computational Mathematics Beijing100094 China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Sichuan Chengdu611731 China

We develop a Macroscopic Auxiliary Asymptotic-Preserving Neural Network (MA-APNN) method to solve the time-dependent linear radiative transfer equations (LRTEs), which have a multi-scale nature and high dimensionality. To achieve this, we utilize the physics-Informed Neural Networks (PINNs) framework and design a new adaptive exponentially weighted Asymptotic-Preserving (AP) loss function, which incorporates the macroscopic auxiliary equation that is derived from the original transfer equation directly and explicitly contains the information of the diffusion limit equation. Thus, as the scale parameter tends to zero, the loss function gradually transitions from the transport state to the diffusion limit state. In addition, the initial data, boundary conditions, and conservation laws serve as the regularization terms for the loss. We present several numerical examples to demonstrate the effectiveness of MA-APNNs. Copyright © 2024, The Authors. All rights reserved.

关键词： Radiative transfer