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Journal of Systems Science & Complexity 2024年第3期37卷 1023-1036页

作者： ZHANG Ziwei shen Hao SU Lei School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan 243002China Anhui Province Key Laboratory of Special Heavy Load Robot and School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan243002China

In this work,an H_(∞)/passive-based secure synchronization control problem is investigated for continuous-time semi-Markov neural networks subject to hybrid attacks,in which hybrid attacks are the combinations of denial-of-service attacks and deception attacks,and they are described by two groups of independent Bernoulli *** this foundation,via the Lyapunov stability theory and linear matrix inequality technology,the H_(∞)/passive-based performance criteria for semi-Markov jump neural networks are ***,an activation function division approach for neural networks is adopted to further reduce the conservatism of the ***,a simulation example is provided to verify the validity and feasibility of the proposed method.

关键词： Activation function division approach deception attacks denial-of-service attacks H_(∞)/passive synchronization semi-Markov jump neural networks

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Toughening ultrastrong low-density steel by textured δ-ferrite lamellas

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Defence Technology（防务技术） 2024年第2期32卷 405-411页

作者： Bin Hu Guosen Zhu Guohui shen Zheng Wang Qinghua Wen Xiao shen Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingXue Yuan Rd.30Beijing 100083China Shougang Research Institute of Technology Yangzhuang Street 69Beijing 100043China Steel Institute RWTH Aachen UniversityIntzestraße 152072AachenGermany

By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, dispersed ultra-fine-retained austenite grains and oriented δ-ferrite lamellas, the latter being due to high Al and Si contents employed for low-density design. This steel shows a superior combination of specific ultimate tensile strength and impact toughness to other ultrastrong steels and has successfully arrested a real steel-cored bullet shot. These are attributed to the densely textured δ-ferrite lamellas that can deflect the propagating cracks until they are trapped and enclosed besides austenite-to-martensite transformation crack closure, leading to more energy consumed before failure. These results suggest a new pathway for toughening ultrastrong lightweight steels.

关键词： Ultrastrong and light steel d-Ferrite lamellas Crack propagation Toughness

Model-free method for LQ mean-field social control problems with one-dimensional state space

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Control Theory and Technology 2024年第3期22卷 479-486页

作者： Zhenhui Xu Tielong shen School of Engineering Tokyo Institute of TechnologyTokyo 152-8550Japan Department of Engineering and Applied Sciences Sophia UniversityTokyo 102-8554Japan

This paper presents a novel model-free method to solve linear quadratic(LQ)mean-field control problems with one-dimensional state space and multiplicative *** focus is on the infinite horizon LQ setting,where the conditions for solution either stabilization or optimization can be formulated as two algebraic Riccati equations(AREs).The proposed approach leverages the integral reinforcement learning technique to iteratively solve the drift-coefficient-dependent stochastic ARE(SARE)and other indefinite ARE,without requiring knowledge of the system dynamics.A numerical example is given to demonstrate the effectiveness of the proposed algorithm.

关键词： Mean-field control Social optima Infinite horizon Reinforcement learning

Eventually homological isomorphisms and Gorenstein projective modules

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Science China Mathematics 2024年第8期67卷 1719-1734页

作者： Yongyun Qin Dawei shen School of Mathematics Yunnan Normal UniversityKunming 650500China School of Mathematics and Statistics Henan UniversityKaifeng 475004China

We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein projective ***,we show that the Auslander-Reiten conjecture and the Gorenstein symmetry conjecture can be reduced by eventually homological *** these results to arrow removal and vertex removal,we describe the Gorenstein projective modules over some non-monomial algebras and verify the Auslander-Reiten conjecture for certain algebras.

关键词： singularity categories Gorenstein defect categories Gorenstein projective modules AuslanderReiten conjecture Gorenstein symmetry conjecture eventually homological isomorphisms

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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method

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Nuclear Science and Techniques 2024年第5期35卷 200-215页

作者： Yi-sheng Hao Zhen Wu shen-shen Gao Rui Qiu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging of Ministry of Education Beijing 100084China Nuctech Company Limited Beijing 100084China

Global variance reduction is a bottleneck in Monte Carlo shielding *** global variance reduction problem requires that the statistical error of the entire space is *** study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program *** proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation *** results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% *** demonstrates that the grid-AIS method is effective in addressing global *** results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational ***,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method.

关键词： Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling

Comprehensive Strategic Planning and Enhancement of China CDC Contributes to High-Quality Development of the National Disease Control and Prevention System

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China CDC weekly 2024年第4期6卷 61-63页

作者： Hongbing shen Director-General of China CDC Academician of the Chinese Academy of EngineeringBeijingChina

The Chinese government has always attached great importance to disease control and prevention ***,the general office of China’s State Council issued the“Guidelines for High-Quality Development of Disease Prevention and Control”(hereinafter referred to as the“Guidelines”)(1).The Guidelines focus on promoting high-quality development of disease control and prevention and the strategic goal of“Healthy China,”providing specific implementation pathways for the development of national disease control and prevention in the new era,including overall planning,restructuring of governance,enhancing core capabilities,strengthening talent development,and improving organizational support.

关键词： prevention attached Quality

Modeling the Epidemic Trend of the 2019 Novel Coronavirus Outbreak in China

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The Innovation 2020年第3期1卷 65-66页

作者： mingwang shen Zhihang Peng Yanni Xiao Lei Zhang China-Australia Joint Research Center for Infectious Diseases School of Public HealthXi'an Jiaotong University Health Science CenterXi'anShaanxi710061PR China Department of Epidemiology and Biostatistics School of Public HealthNanjing Medical UniversityNanjingJiangsu 210029PR China School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'anShaanxi 710049PR China Melbourne Sexual Health Centre Alfred HealthMelbourneAustralia Central Clinical School Faculty of MedicineNursing and Health SciencesMonash UniversityMelbourneVICAustralia Department of Epidemiology and Biostatistics College of Public HealthZhengzhou UniversityZhengzhou 450001HenanChina

A new coronavirus disease(COVID-19)with infection by a novel coronavirus named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has spread globally since December *** 22th September 2020,more than 200 countries worldwide have reported about 30 million confirmed cases and more than 950,000 deaths.1 China has reported a total of 85,307(including 2,758 imported)cases and 4,634 deaths.

关键词： acute respiratory globally

Seizing Opportunities for Further Advancements——Address at the 35th Anniversary Symposium of BES

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Biomedical and Environmental Sciences 2024年第1期37卷 1-2页

作者： shen Hong Bing Chinese Academy of Engineering Director General Chinese Center for Disease Control and Prevention

The year 2023 marks the 35^(th) anniversary of the establishment of Biomedical and Environmental Sciences(BES) by the Chinese Center for Disease Control and Prevention (China CDC).This milestone provides an opportunity to review past achievements and envisage future ***-Five-Year Progress and Achievements In 1988,Professor Chunming Chen,the founding Director General of the Chinese Academy of Preventive Medicine (CAPM,renamed the China CDC in 2002),established the international journal BES to publish research results from Chinese scientists in ***,Professor Chen,along with the renowned toxicologist Professor Frederick Coulston of Albany Medical College in the United States,jointly served as the editors-in-chief,propelling the growth and development of this pioneering journal,while the editorial team is composed exclusively of professionals from the China CDC,and the editorial office was located at the China CDC.

关键词： journal founding jointly

Function-reversible facets enabling SrTiO_(3)nanocrystals for improved photocatalytic hydrogen evolution

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Frontiers in Energy 2024年第1期18卷 101-109页

作者： Bin WANG Bei AN Xiaoqian LI Shaohua shen School of Physics Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter(Ministry of Education)Key Laboratory of Shaanxi for Advanced Materials and Mesoscopic PhysicsXi’an Jiaotong UniversityXi’an 710049China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

It has been widely reported that,for faceted nanocrystals,the two adjacent facets with different band levels contribute to promoted charge separation,and provide active sites for photocatalytic reduction and oxidation reaction,*** such cases,only one family of facets can be used for photocatalytic hydrogen ***,by using SrTiO_(3)nanocrystals enclosed by{023}and{001}facets as a model photocatalyst,this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all *** photo-deposition experiment of CdS provided direct evidence to demonstrate that the{023}facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles,together with the{001}***,the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen,in contrast to those SrTiO_(3)nanocrystals with only{001}facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO_(3)nanocrystals crystal facets photocatalysis hydrogen evolution