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New slant range model and azimuth perturbation resampling based high-squint maneuvering platform SAR imaging

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Journal of Systems Engineering and Electronics 2021年第3期32卷 545-558页

作者： XIONG Xuying LI Gen ma yanheng CHU Lina Institute of UAV Engineering Army Engingeering UniversityShijiazhuang 050003China

Strong spatial variance of the imaging parameters and serious geometric distortion of the image are induced by the acceleration and vertical velocity in a high-squint synthetic aperture radar(SAR)mounted on maneuvering *** this paper,a frequency-domain imaging algorithm is proposed based on a novel slant range model and azimuth perturbation ***,a novel slant range model is presented for mitigating the geometric distortion according to the equal squint angle curve on the ground ***,the correction of azimuth-dependent range cell migration(RCM)is achieved by introducing a high-order time-domain perturbation ***,an azimuth perturbation resampling method is proposed for azimuth *** azimuth resampling and the time-domain perturbation are used for correcting first-order and high-order azimuthal spatial-variant components,*** results illustrate that the proposed algorithm can improve the focusing quality and the geometric distortion correction accuracy of the imaging scene effectively.

关键词： synthetic aperture radar(SAR)imaging maneuvering platform high-squint azimuth perturbation resampling

COMPUTERIZED PREDICTION SySTEM FOR THERMOPHySICAL PROPERTIES

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中国有色金属学会会刊：英文版 1997年第2期7卷 30-34页

作者： Zhang, Jiayun ma, yongjian Zhou, Tuping Lei, Junbo Fang, Xueliang Univ of Science & Technology Beijing Beijing China

ＣＯＭＰＵＴＥＲＩＺＥＤＰＲＥＤＩＣＴＩＯＮＳＹＳＴＥＭＦＯＲＴＨＥＲＭＯＰＨＹＳＩＣＡＬＰＲＯＰＥＲＴＩＥＳ①ＺｈａｎｇＪｉａｙｕｎ，ＭａＹｏｎｇｊｉａｎ，ＺｈｏｕＴｕｐｉｎｇ，ＬｅｉＪｕｎｂｏ，ＦａｎｇＸｕｅｌ... 详细信息

ＣＯＭＰＵＴＥＲＩＺＥＤＰＲＥＤＩＣＴＩＯＮＳＹＳＴＥＭＦＯＲＴＨＥＲＭＯＰＨＹＳＩＣＡＬＰＲＯＰＥＲＴＩＥＳ①ＺｈａｎｇＪｉａｙｕｎ，ＭａＹｏｎｇｊｉａｎ，ＺｈｏｕＴｕｐｉｎｇ，ＬｅｉＪｕｎｂｏ，ＦａｎｇＸｕｅｌｉａｎｇＤｅｐａｒｔｍｅｎｔｏｆＰ...

关键词： prediction of thermophysical property intellectualized data base management system metallic melt ionic melt

Multi-indicator assessment of water environment in government environmental auditing

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Journal of Environmental Sciences 2007年第4期19卷 494-501页

作者： HE Gui-zhen LU yong-long ma Hua WANG Xiao-long Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Graduate University of the Chinese Academy of Sciences Beijing 100039 China

This study focused on a multi-indicator assessment methodology for governmental environmental auditing of water protection programs. The environmental status of Wuli Lak. in China was assessed using the global indicators （driver-status-response） developed by the Commission on Sustainable Development, and four additional indicators proposed by the author： water quality, pollution load, aquatic ecosystem status, and lak. sediment deposition. Various hydrological, chemical, biological and environmental parameters were used to estimate the values of the indicators for assessment of environmental status of the lak. based on time series data sets for twenty years. The indicators proposed can be customized to meeting the needs for particular assessment of water protection programs. This method can be used to evaluate the performance of national environmental protection programs and provide technical support for environmental auditors.

关键词： environmental auditing environmental indicators pollution load lak. ecosystem state assessment

Server-aided immediate and robust user revocation mechanism for SM9

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Cybersecurity 2020年第1期3卷 190-202页

作者： Shuzhou Sun Hui ma Rui Zhang Wenhan Xu State k.y Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China.

As the only approved Identity-Based Encryption scheme in China that is also standardized by ISO,SM9-IBE has been widely adopted in many real-world ***,similar to other IBE standard algorithms,SM9-IBE currently lack. revocation mechanism,which is vital for a real *** still,we find that existing revocable techniques may not be suitable and efficient when applying to *** the widespread use of SM9-IBE,an efficient and robust user revocation mechanism becomes an urgent *** this work.we propose a dedicated server-aided revocation mechanism,which for the first time achieves the secure,immediate and robust user revocation for *** with a compact system model,the proposed method leverages an existing server to perform all heavy work.oads during user revocation,thus leaving no communication and computation costs for the k.y generation center and ***,the mechanism supports k.y-exposure resistance,meaning the user revocation mechanism is robust even if the revocation k.y *** then formally define and prove the *** last,we present theoretical comparisons and an implementation in terms of computational latency and *** results indicate the efficiency and practicability of the proposed mechanism.

关键词： Identity-based encryption SM9 Server-aided immediate and robust revocation Chinese cryptography standard Security proof Performance evaluation

Effects of Carbon Nanotubes by Electrophoretic Deposition on Interlaminar Properties of Two Dimensional Carbon/carbon Composites

维普期刊数据库评论

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Journal of Wuhan University of Technology(materials Science) 2017年第5期32卷 994-1000页

作者：黎云玉 GUO Lingjun LI Hejun ma Haili 宋强 State k.y Laboratory of So'lidification Processing Northwestern Polytechnical University Xi 'an 710072 China Center for Nano Energy materials Northwestern Polytechnical University Xi'an 710072 China

Carbon nanotubes（CNTs） were deposited uniformly on carbon cloth by electrophoretic deposition（EPD）. Thereafter, CNT-doped clothes were stack.d and densified by pyrocarbon via chemical vapor infiltration to fabricate two-dimensional（2 D） carbon/carbon（C/C） composites. Effects of EPD CNTs on interlaminar shear performance and mode Ⅱ interlaminar fracture toughness（GⅡc） of 2 D C/C composites were investigated. Results showed that EPD CNTs were uniformly covered on carbon fibers, acting as a porous coating. Such a CNT coating can obviously enhance the interlaminar shear strength and GⅡc of 2 D C/C composites. With increaing EPD CNTs, the interlaminar shear strength and GⅡc of 2 D C/C composites increase greatly and then decrease, both of which run up to their maximum values, i e, 13.6 MPa and 436.0 J·m-2, when the content of EPD CNTs is 0.54 wt%, 2.27 and 1.45 times of the baseline. Such improvements in interlaminar performance of 2 D C/C composites are mainly beneficial from their increased cohesion of interlaminar matrix, which is caused not only by the direct reinforcing effect of EPD CNT network.but also by the capacity of EPD CNTs to refine pyrocarbon matrix and induce multilayered microstructures that greatly increase the crack.propagation resistance through ＂crack.block.ng and-deflecting mechanisms＂.

关键词： electrophoretic deposition carbon nanotube C/C composite interlaminar performance reinforcing mechanism

Research on Flexural Behavior of Coral Aggregate Reinforced Concrete Beams

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China Ocean Engineering 2018年第5期32卷 593-604页

作者： ma Hai-yan DA Bo yU Hong-fa WU Zhang-yu Department of Civil Engineering Nanjing University of Aeronautics and Astronautics

Through the flexural behavior test of coral aggregate reinforced concrete beams(CARCB) and ordinary Portland reinforced concrete beams(OPRCB), and based on the parameters of concrete types, concrete strength grades and reinforcement ratios, the crack.development, failure mode, midspan deflection and flexural capacity were studied, the relationships of bending moment-midspan deflection, load-longitudinal tensile reinforcement strain, load-maximum crack.width were established, and a calculation model for the flexural capacity of CARCB was suggested. The results showed that with the increase in the reinforcement ratio and concrete strength grade, the crack.bending moment(Mcr)and ultimate bending moment(Mu) of CARCB gradually increased. The characteristics of CARCB and OPRCB are basically the same. Furthermore, through increasing the concrete strength grade and reinforcement ratio, Mcr/Mu could be increased to delay the crack.ng of CARCB. As the load increased, crack.width(w) would also increase. At the beginning of the loading, w increased slowly. And then it increased rapidly when the load reached to the ultimate load, which then led to beam failure. Meanwhile, with a comprehensive consideration of the effects of steel corrosion on the loss of steel section and the decrease of steel yield strength, a more reasonable calculation model for the flexural capacity of CARCB was proposed.

关键词： coral aggregate reinforced concrete beam flexural behavior steel corrosion reinforcement ratio concrete strength calculation model

Evaluation of Equipment Test Data Engineering Standard System Using a Hybrid Model 32

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Evaluation of Equipment Test Data Engineering Standard Syste...

Influence of sintering temperature on the structure and piezoelectric properties of ZnO-modified (Li, Na, k.NbO_(3) lead-free ceramics

第32届中国控制与决策会议

作者： ma yuefei Hu yongtao Chen Feng Army of 92493

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

It is important to overall evaluate the standard system for equipment test data engineering（ETDE） which is a hot topic in equipment test *** do so,a hybrid evaluation model is provided herein based on the fuzzy decision map（FDM） and TOPSIS *** the model,19 indexes with influence relations are extracted to build a multiple-layers index *** then,a modified FDM method is used to derive the weights of the *** the basis of the obtained weights,the TOPSIS method is used to aggregate the global score of the standard ***,a case study is given for illustration.

关键词： Equipment Test Data Engineering Standard System Evaluation Fuzzy Decision map TOPSIS

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International Journal of Minerals,Metallurgy and materials 2012年第9期19卷 843-848页

作者： Hai-tao Li Bo-ping Zhang Wei-gang yang Nan ma School of materials Science and Engineering He'nan University of Science and Technology Luoyang 471003 China School of materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

ZnO-modified (Li, Na, k.NbO3 lead-free ceramics with a nominal composition of Li0.06(Na0.535k..48)0.94NbO3+0.7mol% ZnO (LNk.-ZT) was synthesized normally at 930-1000℃. The Zn ions incorporated into the A-site at a higher sintering temperaVare, which changed LNk.-Z7 to soft piezoelectric ceramics with the mechanical quality factor decreasing from 228 to 192. A phase transition from tetragonal to orthorhombic symmetry was identified by XRD analysis, and the corresponding calculation of lattice parameters was conducted at 970-980℃. Because of such transitional behavior and fine microstructure, the optimized values of piezoelectric coefficient, planar electromechanical coupling coefficient, and relative dielectric constant were obtained.

关键词： piezocemmics niobates zinc oxide modification phase transitions piezoelectricity sintering

Effect of Zn particles on ductility of the accumulative roll-bonding composites

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Science China(Physics,Mechanics & Astronomy) 2015年第10期58卷 107-108页

作者： LIU Chongyu ma MingZhen LIU RiPing yU Liang LUO k.n k.y Laboratory of New Processing Technology for Nonferrous Metal & materials Ministry of Education Guilin University of Technology State k.y Laboratory of Metastable materials Science and Technology Yanshan University Guangxi k.y Laboratory of Universities for Clean Metallurgy and Comprehensive Utilization of Non-ferrous Metal Resources

Over the last five years, accumulative roll bonding （ARB） has been used to produce aluminum-based metal matrix composites （AMMCs） with ultrafine-grained （UFG） structure. Al/Al2O3 [1-3], Al/SiC [4], Al/B4C [5,6], and Al/WC [7] are currently fabricated using ARB because of the resulting highly uniform reinforced particle distribution. ARB composites have higher strength but poorer ductility than unreinforced UFG matrix because stress is concentrated in the reinforced phase-Al matrix interface during tensile process. In the present study, we introduced Al-Zn regions to AI matrix by ARB to obtain AMMCs with high strength and ductility. The dissolution and precipitation of Zn atoms in Al matrix, as well as the effects of Zn on the ductility of AMMCs, were also analyzed.

关键词：铝基复合材料颗粒分布塑性累积 Al/SiC 轧制锌铝/氧化铝