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The application of EPICS in TMSR radiation protection and access control system

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Nuclear Science and Techniques 2016年第2期27卷 58-63页

作者： Li-Feng Han Yong-Zhong Chen Jun Cai Hai-Xia Xu Wen-Bo Huang Ning Zhang Li-Xin Han Peng-Fei Hong Shanghai institute of applied Physics Chinese Academy of Science

To treat technical problems of data acquisition,alarm management, and historical data archiving of radiation protection control system in Thorium Molten Salt Reactor, a network prototype system was designed based on experimental physics and industrial control *** level of many locations in Jiading campus of Shanghai institute of applied Physics is being continuously monitored, and boundaries of accelerator facilities and radiochemical areas are defined by the access control system. In this paper, we introduce the control system design,including human–machine interfaces, alarm system, historical data archiving system, and the software for access control. The software development followed the standard of Capability Maturity Model Integration(CMMIò) Level3, and the software had passed a third-party test, which indicated that the functionality and the reliability could fulfill the requirements of the radiation protection system.

关键词：访问控制系统辐射防护应用能力成熟度模型史诗工业控制系统放射防护历史数据

Multi-axial strain-stiffening elastic potentials with energy bounds:explicit approach based on uniaxial data

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applied Mathematics and Mechanics(English Edition) 2015年第7期36卷 883-894页

作者： Lidan YU Tianfu JIN Zhengnan YIN Heng XIAO Shanghai institute of applied Mathematics and Mechanics Shanghai University

According to the well-known models for rubberlike elasticity with strain- stii^ening effects, the unbounded strain energy is generated with the unlimitedly growing stress when the stretch approaches certain limits. Toward a solution to this issue, an explicit approach is proposed to derive the multi-axial elastic potentials directly from the uniaxial potentials. Then, a new multi-axial potential is presented to characterize the strain-stiffening effect by prescribing suitable forms of uniaxia] potentials so that the strain energy is always bounded as the stress grows to infinity. Numerical examples show good agreement with a number of test data.

关键词： rubberlike elasticity strain limit strain-stiffening effect energy bound,uniaxial data multi-axial potential

A New Approach of data-driven Simulation and its Application to Solar Active Region 12673

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Research in Astronomy and Astrophysics 2024年第12期24卷 45-54页

作者： Zhi-Peng Liu Chao-Wei Jiang Xin-Kai Bian Qing-Jun Liu Peng Zou Xue-Shang Feng institute of Space Science and applied Technology Harbin Institute of Technology

The solar coronal magnetic field is a pivotal element in the study of eruptive phenomena, and understanding its dynamic evolution has long been a focal point in solar physics. Numerical models, driven directly by observation data, serve as indispensable tools in investigating the dynamics of the coronal magnetic field. This paper presents a new approach to electric field inversion, which involves modifying the electric field derived from the DAVE4VM velocity field using ideal Ohm's law. The time series of the modified electric field is used as a boundary condition to drive a magnetohydrodynamics model, which is applied to simulate the magnetic field evolution of active region12673. The simulation results demonstrate that our method enhances the magnetic energy injection through the bottom boundary, as compared with energy injection calculated directly from the DAVE4VM code, and reproduces the evolution of the photospheric magnetic flux. The coronal magnetic field structure is also in morphological similarity to the coronal loops. This new approach will be applied to the high-accuracy simulation of eruption phenomena and provide more details on the dynamical evolution of the coronal magnetic field.

关键词： magnetohydrodynamics (MHD) methods: numerical Sun: coronal mass ejections (CMEs) Sun: flares

Coupled Matrix Factorization for Question Similarity

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Chinese Journal of Electronics 2016年第4期25卷 665-671页

作者： WEI Chuyuan LI Fangfang ZHAN Qiang FAN Xiongzhong School of Computer Science and Technology Beijing Institute of Technology Department of Computer Beijing University of Civil Engineering and Architecture Advanced analytics institute University of TechnologySydneyAustralia

Community question answering(CQA)has provided an increasingly popular service where users ask and answer questions and access historical questionanswer *** a fundamental task in CQA,question similarity measure is to compute the similarity between the queried question and the historical questions which have been solved by other *** mine and use the most important semantic features as the semantic representation of questions,and try to incorporate the couplings of semantic features into vector space *** propose Coupled question similarity(CQS) model,and compute the similarity in matrix factorization *** conducted on real CQA data sets demonstrate that with the incorporation of such couplings,the performance of sentence similarity is improved compared to a variety of baseline methods significantly.

关键词： Sentence similarity Community question answering(CQA) Matrix factorization(MF) Coupled question similarity(CQS)

Single and double Auger decay of 4f-ionized mercury including cascade and direct processes

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Chinese Physics B 2018年第6期27卷 244-250页

作者： Yu-Long Ma Fu-Yang Zhou Zhen-Qi Liu Yi-Zhi Qu College of Material Sciences and Optoelectronic Technology University of Chinese Academy of Sciences Beijing 100049 China data Center for High Energy Density Physics Institute of Applied Physics and Computational Mathematics Beijing 100088 China

Single（SA） and double（DA） Auger decay including cascade and direct processes are investigated for Hg 4 f^（-1） with multiconfiguration Dirac–Fock method and two-step approaches, i.e., knockout and shakeoff mechanisms. Due to the computational effort, only the major transitions are considered to describe the SA and DA decays for the Hg＋ions with complex electronic configurations. In order to estimate the Auger transition energies and amplitudes, the reference configuration sets producing the configuration state functions are carefully chosen for balancing electron correlations among the successive singly, doubly and triply ionized mercury. The Auger rates and electron spectra, DA probabilities as well as the populations of the final Hg^（3＋）states are obtained. Our results well explain the recent experimental data about the 4 f hole states of Hg[Palaudoux J et al., Phys. Rev. A 91 012513（2015）], and could provide guidance for further studies on complex *** for the DA decay, the contributions of the direct processes, which are neglected in their calculations, are found to be important, accounting for as high as about 38% and 34% of the total DA decays for the 4 f（7/2）^（-1） and 4 f（5/2）^（-1）, respectively.

关键词： single Auger cascade double Auger direct double Auger Hg 4f^-1

Urban Sensing Based on Mobile Phone data:Approaches,Applications,and Challenges

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 627-637页

作者： Mohammadhossein Ghahramani MengChu Zhou Gang Wang Insight Centre for data analytics University College DublinDublin 4Ireland IEEE Helen and John C.Hartmann Department of Electrical and Computer Engineering New Jersey Institute of TechnologyMacao 999078China institute of Systems Engineering Macao University of Science and TechnologyMacao 999078China China Telecom at Macao Macao 999078China

data volume grows explosively with the proliferation of powerful smartphones and innovative mobile *** ability to accurately and extensively monitor and analyze these data is *** concern in cellular data analysis is related to human beings and their *** to the potential value that lies behind these massive data,there have been different proposed approaches for understanding corresponding *** that end,analyzing people's activities,e.g.,counting them at fixed locations and tracking them by generating origindestination matrices is *** former can be used to determine the utilization of assets like roads and city *** latter is valuable when planning transport *** insights allow a government to predict the adoption of new roads,new public transport routes,modification of existing infrastructure,and detection of congestion zones,resulting in more efficient designs and *** data exploration can help research in various fields,e.g.,urban planning,transportation,health care,and business *** can also help organizations in decision making,policy implementation,monitoring,and evaluation at all *** work aims to review the methods and techniques that have been implemented to discover knowledge from mobile phone *** classify these existing methods and present a taxonomy of the related work by discussing their pros and cons.

关键词： Big data analysis human mobility origin destination matrices smart infrastructure urban planning

High-Dimensional Volatility Matrix Estimation with Cross-Sectional Dependent and Heavy-Tailed Microstructural Noise

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Journal of Systems Science & Complexity 2023年第5期36卷 2125-2154页

作者： LIANG Wanwan WU Ben FAN Xinyan JING Bingyi ZHANG Bo Center for applied Statistics School of StatisticsInstitute of Probability and StatisticsRenmin University of ChinaBeijing 100086China Department of Statistics&data Science Southern University of Science and TechnologyShenzhen 518055China

The estimates of the high-dimensional volatility matrix based on high-frequency data play a pivotal role in many financial ***,most existing studies have been built on the sub-Gaussian and cross-sectional independence assumptions of microstructure noise,which are typically violated in the financial *** this paper,the authors proposed a new robust volatility matrix estimator,with very mild assumptions on the cross-sectional dependence and tail behaviors of the noises,and demonstrated that it can achieve the optimal convergence rate n-1/***,the proposed model offered better explanatory and predictive powers by decomposing the estimator into low-rank and sparse components,using an appropriate regularization *** studies demonstrated that the proposed estimator outperforms its competitors under various dependence structures of microstructure ***,an extensive analysis of the high-frequency data for stocks in the Shenzhen Stock Exchange of China demonstrated the practical effectiveness of the estimator.

关键词： Cross-sectional dependence high-dimensional data high-frequency data integrated volatility matrix market microstructure noise

Microscopic study of 7Li-nucleus potential

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Chinese Physics C 2020年第5期44卷 106-113页

作者： Wen-Di Chen Hai-Rui Guo Wei-Li Sun Tao Ye Yang-Jun Ying Yin-Lu Han Qing-Biao Shen Graduate School of China Academy of Engineering Physics Beijing 100088China institute of applied Physics and Computational Mathematics Beijing 100094China Key Laboratory of Nuclear data China Institute of Atomic EnergyBeijing 102413China

A microscopic approach is employed to study the optical potential for the 7Li-nucleus interaction system without any free *** is obtained by folding the microscopic optical potentials of the constituent nucleons of 7Li over their density *** employ an isospin-dependent nucleon microscopic optical potential,which is based on the Skyrme nucleon-nucleon effective interaction and derived using the Green's function method,as the nucleon optical *** harmonic oscillator shell model is used to describe the internal wave function of 7Li and obtain the nucleon density *** 7Li microscopic optical potential is used to predict the reaction cross-sections and elastic scattering angular distributions for the target range from 27Al to 208Pb and energy range below 450 ***,the results can reproduce the measured data reasonably *** addition,the microscopic optical potential is comparable to a global phenomenological optical potential by fitting the presently existing measured data.

关键词： 7 Li microscopic optical potential 7 Li elastic scattering folding model

Monte Carlo simulation and parameterized treatment on the effect of nuclear elastic scattering in high-energy proton radiography

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Chinese Physics C 2015年第7期39卷 97-101页

作者：许海波郑娜 institute of applied Physics and Computational Mathematics

A version of Geant4 has been developed to treat high-energy proton radiography. This article presents the results of calculations simulating the effects of nuclear elastic scattering for various test step wedges. Comparisons with experimental data are also presented. The traditional expressions of the transmission should be correct if the angle distribution of the scattering is Gaussian multiple Coulomb scattering. The mean free path（which depends on the collimator angle） and the radiation length are treated as empirical parameters, according to transmission as a function of thickness obtained by simulations. The results can be used in density reconstruction, which depends on the transmission expressions.

关键词： proton radiography multiple Coulomb scattering angle collimator nuclear elastic scattering Geant4