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Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng Zi-Huang Cao Man I Lam Ran Li Hao Tian Da-Yi Yin yuan-Yu yang Xin Zhang Dong-wei Fan Yi-Qiao Dong Xin-Feng Li wei wang Long Li Hugh RAJones Yi-Han Tao Jia-Lu Nie Pei-Pei wang Mao-yuan Liu He-jun yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK beijing University of Technology Beijing 100124China

The china Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

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NLOS error mitigation with information fusion algorithm for UWB ranging systems

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The Journal of china Universities of Posts and Telecommunications 2012年第2期19卷 22-29页

作者： JIANG Xiang-yuan ZHANG Huan-shui wang wei school of Control Science and engineering Shandong UniversityJinan 250061China

This article puts forward a scalar weighting information fusion （IF） smoother with modified biased Kalman filter （BKF） and maximum likelihood estimation （MLE） to mitigate the ranging errors in ultra wide band （UWB） systems. The information fusion algorithm uses both the time of arrival （TOA） and received signal strength （RSS） measurement data to improve the ranging accuracy. At first, the ranging protocol of IEEE 802.15.4a acts as a multi-sensor system with multi-scale sampling. Then the scalar-based IF smoother accurately estimates the range measurement in the line of sight （LOS） and non-line of sight （NLOS） condition of UWB sensor network, during which the effectiveness of the IF in mitigating errors is especially focused during the LOS/NLOS transitions. Simulation results show that the proposed hybrid TOA-RSS fusion approach indicates a performance improvement compared with the usual TOA-only and other IF method, and the estimated ranging metrics can be used for achieving higher accuracy in location estimation and target tracking.

关键词： NLOS error mitigation biased Kalman filter maximum likelihood estimation information fusion UWB ranging system

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Demonstration of orbital angular momentum channel healing using a Fabry‐Pérot cavity

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Opto-Electronic Advances 2018年第5期1卷 1-6页

作者： Shibiao wei Dapeng wang Jiao Lin Xiaocong yuan Nanophotonics Research Centre Shenzhen Key Laboratory of Micro-Scale Optical Information Technology Shenzhen University Shenzhen 518060 China school of engineering RMIT University Melbourne VIC 3000 Australia

Orbital angular momentum （OAM） mode division provides a promising solution to push past the already exhausted available degrees of freedom available in conventional optical communications. Nevertheless, the practical deploymentof OAM within a free-space optical （FSO） communications system is still hampered by a major challenge, namely that OAM-based FSO links are vulnerable to disturbances. Though several techniques, such as using various non-diffraction beams and multiple transmit–receive apertures, are proposed to alleviate the influence of disturbances, these techniquessignificantly reduce the performance with regard to combating single fading for spatial blockages of the laser beam byobstructions. In this work, we initially demonstrate that a Fabry-Pérot resonant cavity has the ability to implement OAM mode healing, even for a blocking percentage of over 50%. Consequently, the proposed method will expand the use ofOAM in the FSO secure communications and quantum encryption fields.

关键词： optical communication orbital angular momentum Fabry-Pérot cavity

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Monopole effects, core excitations, and β decay in the A = 130 hole nuclei near ^(132)Sn

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Chinese Physics C 2019年第5期43卷 35-40页

作者： Han-kui wang Zhi-Hong Li Cen-Xi yuan Zhi-Qiang Chen Ning wang wei Qin Yi-Qi He College of Physics and Telecommunication engineering Zhoukou Normal University china Institute of Atomic Energy Sino-French Institute of Nuclear engineering and Technology Sun Yat-Sen University school of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University College of mathematics and statistics Zhoukou Normal University

The proton and neutron cross-shell excitations across the Z = 50 shell are investigated in the southwest quadrant of ^(132) Sn by large-scale shell-model calculations with extended pairing and multipole-multipole force. The model space allows proton(neutron) core excitations, and both the low-and high-energy states for ^(130) In are well described, as found by comparison with the experimental data. The monopole effects between the proton orbit and neutron orbit are studied as the new monopole correction that perfectly reproduces the first 1^+ level in ^(130) In. The energy interval of proton(neutron) core excitations in ^(130) In lies in the range of 4.5-6.5(2.0-4.1) MeV, and the high energy yrast states are predicted as neutron core excitations. The decays are calculated among the A=130 nuclei of ^(130) In, ^(130) Sn and ^(130) Cd.

关键词： monopole effects core-excitations β decay hole nuclei

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Virtual network function scheduling via multilayer encoding genetic algorithm with distributed bandwidth allocation

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Science china(information Sciences) 2018年第9期61卷 93-111页

作者： Quan yuan Hongbo TANG wei YOU Xiaolei wang Yu ZHAO National Digital Switching System engineering and Technological Research Center

Network function virtualization represents a revolutionary approach to network service deployment. This software-oriented approach for virtual network functions(VNFs) deployment enables more flexible and dynamic network services to meet diversified demands. To minimize the execution time of all VNFs in service function chains, VNF scheduling must be addressed. In this paper, we improve upon the flexible job-shop model by introducing the process of bandwidth allocation. First, we propose a multilayer encoding genetic algorithm to solve the VNF scheduling model. In addition, we design a distributed method for bandwidth allocation based on the Nash bargaining solution. Finally, by combining the genetic algorithm with distributed bandwidth allocation, we present a heuristic algorithm that solves the VNF scheduling problem in one stage. Using a multilayer encoding genetic algorithm, we simplify the constraints of the VNF scheduling problem and reduce its time complexity. At the same time, our Nash game solution refines the granularity of bandwidth allocation to further reduce the transmission delay between VNFs. The effectiveness of our proposed heuristic algorithm is verified through numerical evaluation. Compared with existing approaches,our method exhibits shorter scheduling time and reduces CPU time by 45% in simulated scenarios.

关键词： network function virtualization virtual network function scheduling genetic algorithm bandwidth allocation convex optimization

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基于语言神经网络的知识获取方法研究及在智能教学系统中的应用

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系统工程理论与实践 2004年第2期24卷 68-73,115页

作者：韦卫星莫赞廖义奎广西民族学院电子与通信工程学院广西南宁530006 华中科技大学控制科学与工程系湖北武汉430074 广西海恒电子信息研究所广西南宁530006

　提出了一种基于语言神经网络的知识获取方法,该方法利用语言神经元,对具有开区域的连续输入变量,自动产生相应的语言变量输出,讨论了相应的神经网络训练和知识获取方法,所获取的知识以If-Then的规则形式表示,具有简洁、紧凑、不必进... 详细信息

　提出了一种基于语言神经网络的知识获取方法,该方法利用语言神经元,对具有开区域的连续输入变量,自动产生相应的语言变量输出,讨论了相应的神经网络训练和知识获取方法,所获取的知识以If-Then的规则形式表示,具有简洁、紧凑、不必进一步化简、易于理解等特点,并给出在智能教学系统中获取专家领域知识的应用实例.

关键词：神经网络语言神经元规则获取智能教学系统

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In situ resource utilization of lunar soil for highly efficient extraterrestrial fuel and oxygen supply

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National Science Review 2023年第2期10卷 224-231页

作者： yuan Zhong Jingxiang Low Qing Zhu Yawen Jiang Xiwen Yu Xinyu wang Fei Zhang weiwei Shang Ran Long Yingfang Yao wei Yao Jun Jiang Yi Luo weihua wang Jinlong yang Zhigang Zou Yujie Xiong Hefei National Research Center for Physical Sciences at the Microscale School of Chemistry and Materials Science National Synchrotron Radiation Laboratory School of Information Science and TechnologyUniversity of Science and Technology of China Eco-Materials and Renewable Energy Research Center (ERERC) Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State MicrostructuresSchool of PhysicsCollaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesNanjing University Qian Xuesen Laboratory of Space Technology China Academy of Space Technology

Building up a lunar settlement is the ultimate aim of lunar ***, limited fuel and oxygen supplies restrict human survival on the ***,we demonstrate the in situ resource utilization of lunar soil for extraterrestrial fuel and oxygen production,which may power up our solely natural satellite and supply respiratory ***,the lunar soil is loaded with Cu species and employed for electro catalytic CO2conversion,demonstrating significant production of *** addition,the selected component in lunar soil(***3) loaded with Cu can reach a CH4F aradaic efficiency of 72.05% with a CH4production rate of 0.8 mL/min at 600 mA/***,an O2production rate of 2.3 mL/min can be ***,we demonstrate that our developed process starting from catalyst preparation to electrocatalytic CO2conversion is so accessible that it can be operated in an unmmaned manner via a robotic *** a highly efficient extraterrestrial fuel and oxygen production system is expected to push forward the development of mankind’s civilization toward an extraterrestrial settlement.

关键词： Chang’E-5 lunar soil fuel production CO2 conversion extraterrestrial settlement in situ resource utilization

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Joint power control and passive beamforming optimization in RIS-assisted anti-jamming communication

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Frontiers of information Technology & Electronic engineering 2023年第12期24卷 1791-1802页

作者： yang LIU kui XU Xiaochen XIA wei XIE Nan MA Jianhui XU school of Communication engineering Army Engineering University of PLANanjing210007China

Due to the openness of the wireless propagation environment,wireless networks are highly susceptible to malicious jamming,which significantly impacts their legitimate communication *** study investigates a reconfigurable intelligent surface(RIS)assisted anti-jamming communication ***,the objective is to enhance the system’s anti-jamming performance by optimizing the transmitting power of the base station and the passive beamforming of the *** into account the dynamic and unpredictable nature of a smart jammer,the problem of joint optimization of transmitting power and RIS reflection coefficients is modeled as a Markov decision process(MDP).To tackle the complex and coupled decision problem,we propose a learning framework based on the double deep Q-network(DDQN)to improve the system achievable rate and energy *** most power-domain jamming mitigation methods that require information on the jamming power,the proposed DDQN algorithm is better able to adapt to dynamic and unknown environments without relying on the prior information about jamming ***,simulation results demonstrate that the proposed algorithm outperforms multi-armed bandit(MAB)and deep Q-network(DQN)schemes in terms of the anti-jamming performance and energy efficiency.

关键词： Reconfigurable intelligent surface(RIS) Power control Anti-jamming Reinforcement learning(RL)

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Temperature Dependence of Electrical Characteristics in Indium-Zinc-Oxide Thin Film Transistors from 10 K to 400 K

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Chinese Physics Letters 2018年第9期35卷 95-98页

作者： yuan Liu Li wang Shu-Ting Cai Ya-Yi Chen Rongsheng Chen Xiao-Ming Xiongl kui-wei Geng school of Automation Guangdong University of TechnologyGuangzhou 510006 school of Electronic and information engineering South China University of TechnologyGuangzhou 510640 Key Laboratory of Silicon Device Technology Chinese Academy of SciencesBeijing 100029

The transfer characteristics of amorphous indium-zinc-oxide thin film transistors are measured in the temperature range of 10-400K. The variation of electrical parameters （threshold voltage, field effect mobility, sub-threshold swing, and leafage current） with decreasing temperature are then extracted and analyzed. Moreover, the dom- inated carrier transport mechanisms at different temperature regions are investigated. The experimental data show that the carrier transport mechanism may change from trap-limited conduction to variable range hopping conduction at lower temperature. Moreover, the field effect mobilities are also extracted and simulated at various temperatures.

关键词： In exp Temperature Dependence of Electrical Characteristics in Indium-Zinc-Oxide Thin Film Transistors from 10 K to 400 K

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A Conservative Modification to the Ghost Fluid Method for Compressible Multiphase Flows

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Communications in Computational Physics 2011年第9期10卷 785-806页

作者： wei Liu Li yuan Chi-wang Shu Institute of Computational Mathematics and Scientific/engineering Computing Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Division of Applied Mathematics Brown UniversityProvidence RI 02912USA.

A conservative modification to the ghost fluid method(GFM)is developed for compressible multiphase *** motivation is to eliminate or reduce the conservation error of the GFM without affecting its *** track the conservative variables near the material interface and use this information to modify the numerical solution for an interfacing cell when the interface has passed the *** modification procedure can be used on the GFM with any base *** this paper we use the fifth order finite difference WENO scheme for the spatial discretization and the third order TVD Runge-Kutta method for the time *** level set method is used to capture the *** experiments show that the method is at least mass and momentum conservative and is in general comparable in numerical resolution with the original GFM.

关键词： WENO scheme ghost fluid method(GFM) mass conservation multiphase flow

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