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Chinese Physics B 2020年第2期29卷 183-189页

作者： Yin-Li Kuang Liang Fang Xiang Peng Xin Cheng Hui Zhang en-hai liu Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China University of Chinese Academy of Sciences Beijing 100049China

Doppler asymmetric spatial heterodyne spectroscopy(DASH)technique has developed rapidly in passive Doppler-shift measurements of atmospheric emission lines over the last *** the advantages of high phase shift sensitivity,compact,and rugged structure,DASH is proposed to be used for celestial autonomous navigation based on Doppler radial velocity measurement in this *** atmospheric emission lines,almost all targeted lines in the research field of deep-space exploration are the absorption lines of stars,so a mathematical model for the Doppler-shift measurements of absorption lines with a DASH interferometer is *** to the analysis of the components of the interferogram received by the detector array,we find that the interferogram generated only by absorption lines in a passband can be extracted and processed by a method similar to the approach to studying the emission *** the end,numerical simulation experiments of Doppler-shift measurements of absorption lines are carried *** simulation results show that the relative errors of the retrieved speeds are less than 0.7%under ideal conditions,proving the feasibility of measuring Doppler shifts of absorption lines by DASH instruments.

关键词： Doppler asymmetric spatial heterodyne spectroscopy(DASH) Doppler-shift measurement absorption line celestial autonomous navigation

A method and results of color calibration for the Chang'e-3 terrain camera and panoramic camera

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Research in Astronomy and Astrophysics 2014年第12期14卷 1557-1566页

作者： Xin Ren Chun-Lai Li Jian-Jun liu Fen-Fei Wang Jian-Feng Yang en-hai liu Bin Xue Ru-Jin Zhao Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Institute of Optics and Electronics Chinese Academy of Sciences

The terrain camera （TCAM） and panoramic camera （PCAM） are two of the major scientific payloads installed on the lander and rover of the Chang＇e 3 mission re- spectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon＇s surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image qual- ity has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that：（1） Compared with uncor- rected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. （2） The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively.

关键词： Moon -- methods: data analysis -- techniques: image processing

Payload topography camera of Chang'e-3

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Research in Astronomy and Astrophysics 2015年第11期15卷 1881-1892页

作者： Guo-Bin Yu en-hai liu Ru-Jin Zhao Jie Zhong Xiang-Dong Zhou Wu-Lin Zhou Jin Wang Yuan-Pei Chen Yong-Jie Hao Institute of Optics and Electronics Chinese Academy of Sciences

Chang＇e-3 was China＇s first soft-landing lunar probe that achieved a successful roving exploration on the Moon. A topography camera functioning as the lander＇s “eye” was one of the main scientific payloads installed on the lander. It was composed of a camera probe, an electronic component that performed image compression, and a cable assembly. Its exploration mission was to obtain optical images of the lunar topography in the landing zone for investigation and research. It also observed rover movement on the lunar surface and finished taking pictures of the lander and rover. After starting up successfully, the topography camera obtained static images and video of rover movement from different directions, 360？panoramic pictures of the lunar surface around the lander from multiple angles, and numerous pictures of the Earth. All images of the rover, lunar surface, and the Earth were clear, and those of the Chinese national flag were recorded in true color. This paper describes the exploration mission, system design, working principle, quality assessment of image compression, and color correction of the topography camera. Finally, test results from the lunar surface are provided to serve as a reference for scientific data processing and application.

关键词： camera correction rover lunar topography lander PSNR directions pixel coordinates

Improved Segmented Belief Propagation List Decoding for Polar Codes with Bit-Flipping

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China Communications 2024年第3期21卷 19-36页

作者： Mao Yinyou Yang Dong liu Xingcheng Zou en School of Electronics and Information Technology(SEIT) Sun Yat-sen University(SYSU)Guangzhou 510006China School of Information Science Guangzhou Xinhua UniversityGuangzhou 510520China Southern Marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Belief propagation list(BPL) decoding for polar codes has attracted more attention due to its inherent parallel nature. However, a large gap still exists with CRC-aided SCL(CA-SCL) *** this work, an improved segmented belief propagation list decoding based on bit flipping(SBPL-BF) is proposed. On the one hand, the proposed algorithm makes use of the cooperative characteristic in BPL decoding such that the codeword is decoded in different BP decoders. Based on this characteristic, the unreliable bits for flipping could be split into multiple subblocks and could be flipped in different decoders simultaneously. On the other hand, a more flexible and effective processing strategy for the priori information of the unfrozen bits that do not need to be flipped is designed to improve the decoding convergence. In addition, this is the first proposal in BPL decoding which jointly optimizes the bit flipping of the information bits and the code bits. In particular, for bit flipping of the code bits, a H-matrix aided bit-flipping algorithm is designed to enhance the accuracy in identifying erroneous code bits. The simulation results show that the proposed algorithm significantly improves the errorcorrection performance of BPL decoding for medium and long codes. It is more than 0.25 d B better than the state-of-the-art BPL decoding at a block error rate(BLER) of 10^(-5), and outperforms CA-SCL decoding in the low signal-to-noise(SNR) region for(1024, 0.5)polar codes.

关键词： belief propagation list(BPL)decoding bit-flipping polar codes segmented CRC

Effect of quenching cooling rate on residual stress and microstructure evolution of 6061 aluminum alloy

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Journal of Central South University 2024年第7期31卷 2167-2180页

作者： HUANG Ke YI You-ping HUANG Shi-quan HE hai-lin liu Jie HUA Hong-en TANG Yun-jian Research Institute of Light Alloy Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Changsha 410083China School of Mechanical and Electrical engineering Central South UniversityChangsha 410083China

In this study,the cooling rate was manipulated by quenching with water of different temperatures(30,60 and 100℃).Surface and internal residual stresses in the quenched 6061 aluminum alloy samples were measured using hole-drilling and crack compliance methods,***,the processability of the quenched samples was evaluated at cryogenic *** mechanical properties of the as-aged samples were assessed,and microstructure evolution was *** surface residual stresses of samples W30℃,W60℃and W100℃is−178.7,−161.7 and−117.2 MPa,respectively along x-direction,respectively;and−191.2,−172.1 and−126.2 MPa,respectively along *** sample quenched in boiling water displaying the lowest residual stress(~34%and~60%reduction in the surface and core).The generation and distribution of quenching residual stress could be attributed to the lattice distortion *** plasticity was also exhibited in the samples with relatively low quenching cooling rates at cryogenic *** strengthes of the as-aged samples are 291.2 to 270.1 MPa as the quenching water temperature increase from 30℃to 100℃.Fine and homogeneous β"phases were observed in the as-aged sample quenched with boiling water due to the clusters and Guinier-Preston zones(GP zones)premature precipitated during quenching process.

关键词： 6061 aluminum alloy residual stress cooling rate cryogenic cooling mechanical properties microstructure evolution

Advances in the Application of Molecular Diagnostic Techniques to Brucellosis

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Biomedical and environmental Sciences 2024年第7期37卷 790-794页

作者： haiwen liu hai Jiang School of Public Health Baotou Medical CollegeBaotou 014040Inner Mongolia AutonomousChina National Key Laboratory of Intelligent Tracing and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Brucellosis is a zoonotic infectious and allergic disease caused by Brucella *** occurs worldwide and has had a huge economic impact on the livestock industry in many countries and *** has become a major public health *** is an endoparasitic,non-motile Gram-negative bacterium capable of surviving within a diverse range of domestic animal hosts.

关键词： problem diverse capable

Isogeometric Analysis for the Arbitrary AFG Microbeam with Two-Phase Nonlocal Stress-Driven Model

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Acta Mechanica Solida Sinica 2024年第2期37卷 341-360页

作者： Pei-Liang Bian Zhaowei liu hai Qing Tiantang Yu Department of engineering Mechanics Hohai UniversityNanjing211100China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

Scale effects play critical roles in the mechanical responses of *** isogeometric analysis was developed here to investigate the mechanical responses of an axially functionally graded *** Euler–Bernoulli beam model was utilized,and size effects in the structure were modeled with a stress-driven two-phase local/nonlocal integral *** governing equation of microstructures was given in an equivalent differential form with two additional constitutive boundary *** framework was verified and utilized to analyze the microbeam’s static and dynamic mechanical *** present work showed great potential for modeling various types of functionally graded microstructures.

关键词： Isogeometric analysis Size effect Functionally graded material Nonlocal theory Euler-Bernoulli beam

Ferromagnetism and insulating behavior with a logarithmic temperature dependence of resistivity in Pb_(10-x)Cux(PO_(4))_(6)O

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 106-111页

作者： Yuhang Zhang Cong liu Xiyu Zhu hai-Hu Wen Center for Superconducting Physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Recent claim of discovering above-room-temperature superconductivity(Tc≈400 K)at ambient pressure in copper doped apatite Pb10(PO_(4))_(6)O has stimulated world-wide enthusiasm and impulse of motion.A lot of follow-up works have been carried out with controversial *** check whether superconductivity is really present or absent in the material,we need samples which should have a rather pure phase of Pb_(10-x)Cux(PO_(4))_(6)*** we report the characterization results from the Pb_(10-x)Cux(PO_(4))_(6)O with a fraction of about 97 wt.%inferred from the fitting to the X-ray diffraction pattern,if assuming Cu2S as the only *** resistivity measurements show that it is a semiconductor characterized roughly by a ln(1/T)temperature dependence in wide temperature region without trace of *** measurements show that it has a general ferromagnetic signal with a weak superparamagnetic *** grains of the sample show clear interactions with a Nb Fe B *** detected Cu concentration is much lower than the expected nominal *** results show the absence of metallicity and superconductivity in Pb_(10-x)Cux(PO_(4))_(6)O at ambient pressure,and suggest the presence of strong correlation effect.

关键词： superconductivity Pb10(PO4)6O ferromagnetic correlation effect

Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica Sinica,english Series 2024年第4期40卷 1143-1160页

作者： Jing ZHAO Chun Mei GAN Zhen hai liu School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

A hybrid memory architecture supporting fine-grained data migration

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Frontiers of Computer Science 2024年第2期18卷 31-41页

作者： Ye CHI Jianhui YUE Xiaofei LIAO haikun liu hai JIN National engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Department of Computer Science Michigan Technological UniversityMichigan 49931USA

Hybrid memory systems composed of dynamic random access memory(DRAM)and Non-volatile memory(NVM)often exploit page migration technologies to fully take the advantages of different memory *** previous proposals usually migrate data at a granularity of 4 KB pages,and thus waste memory bandwidth and DRAM *** this paper,we propose Mocha,a non-hierarchical architecture that organizes DRAM and NVM in a flat address space physically,but manages them in a cache/memory *** the commercial NVM device-Intel Optane DC Persistent Memory Modules(DCPMM)actually access the physical media at a granularity of 256 bytes(an Optane block),we manage the DRAM cache at the 256-byte size to adapt to this feature of *** design not only enables fine-grained data migration and management for the DRAM cache,but also avoids write amplification for Intel Optane *** also create an Indirect Address Cache(IAC)in Hybrid Memory Controller(HMC)and propose a reverse address mapping table in the DRAM to speed up address translation and cache ***,we exploit a utility-based caching mechanism to filter cold blocks in the NVM,and further improve the efficiency of the DRAM *** implement Mocha in an architectural *** results show that Mocha can improve application performance by 8.2%on average(up to 24.6%),reduce 6.9%energy consumption and 25.9%data migration traffic on average,compared with a typical hybrid memory architecture-HSCC.

关键词： non-volatile memory hybrid memory system data migration fine-grained caching