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直升机技术 2010年第1期 43-46页

作者：章剑方凤鸯金友林中国直升机设计研究所江西景德镇333001 景德镇高等专科学校江西景德镇333001

本文介绍了运用Lms test. lab软件的模态分析为试验手段来诊断航天员超重训练设备所存在的故障,通过模态分析试验研究表明系统刚度变化对系统自振频率的影响,动力系统轴承齿轮间摩损的间隙以及环境因数如地基沉降对系统频率的影响等。

关键词： Lms test. lab 超重训练设备模态分析刚度

Study on the relative radiometric correction of CBERS satellite CCD image

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Science China(Technological Sciences) 2005年第S2期48卷 12-28页

作者： GUO Jianning, YU Jin, ZENG Yong, XU Jianyan, PAN Zhiqiang & HOU Minghui China Center for Resource Satellite Data and Application, Beijing 100830, China China Ctr Resource Satellite Data & Applicat Beijing 100830 Peoples R China

The main payload on CBERS-01/02 of China-Brazil Earth Resources Satellite (CBERS) is a push-broom CCD camera with moderate spatial and radiant resolution. Because at lab the data for calibration at satellite assembly stage were unable to be collected, and also because the onboard calibrator after launch was in a different state from imaging, the calibration of CCD image got a series of difficulties involved. In practice, two methods are used in the processing on the ground station: One is extracting calibration data by statistics from the image itself, and the other is the method of histogram match. It was proved that the latter can calibrate the image much better, because it can remove the effect of unstable response of the camera largely and also can overcome the nonlinearity of the camera basically by using Look-Up Table (LUT) calculated from histogram statistics of different temporal images. Considering the problems of CBERS-01, a lot of calibration test. were done before the launch of CBERS-02, in which a set of lab coefficients for relative calibration was formulated after the data collection by using integration-hemisphere in the stage of satellite assembly test. During the on-orbit test. it was found that the calibration result from such coefficients was not satisfying, especially there being response difference between 3 detector arrays, which was attributed to the unstable dark currents of the CCD camera. This paper comes up with a statistic method to remove such response difference. In this method the middle detector array was used as reference to find the response differences of adjacent similar features between these arrays and it was proved to have a broad adaptability.

关键词： CBERS satellite CCD camera relative radiometric calibration relative radiometric correction assembly test.

Stress singularity near the end of a cylindrical interface and the linear elasticity of push-in test.

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Science China(Technological Sciences) 1998年第5期41卷 471-481页

作者：王清嵇醒王远功 1. Department of Engineering Mechanics and Technology Tongji University 200092 Shanghai China

Investigated is the push-in test.used to determine the interfacial strength of fiber-reinforced composites via the method of singular integral equation. Singularity analysis shows that stresses near the end for an intact interface have a power singularity, and the singularity index is only dependent on the material constants of the fiber and the matrix. In order to describe the interfacial strength at the initial debonding of the push-in test. critical interfacial shear stress intensity factor and the related singularity index are adopted. This interfacial strength characteristic parameter is applied to analysis of the push-in test.results of carbon fiber reinforced epoxy resin composites.

关键词： interfacial strength cylindrical interface interface end stress singularity stress intensity factor singular integral equation push-in test.

Non-unbiasedness of Cramer-von Mises test

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Science China Mathematics 2000年第10期43卷 1046-1050页

作者：陈希孺 Department of Mathematics Graduate School at Beijing University of Science and Technology of China Beijing 100039 China This paper shows that for any given level of significance α∈(01) and any sample size n the Cramer-von Mises test is not unbiased.

This paper shows that for any given level of significance α∈ (0,1), and any sample size n, the Cramer-von Mises test.is not unbiased.

关键词： Cramer-von Mises test unbiased test.

Contemporary crustal deformation of the Chinese continent and tectonic block model

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Science China Earth Sciences 2003年第z2期46卷 25-40页

作者： WANG Min (王敏) SHEN Zhengkang (沈正康) NIU Zhijun (牛之俊) ZHANG Zusheng (张祖胜) SUN Hanrong (孙汉荣) GAN Weijun (甘卫军) WANG Qi (王琪) REN Qun (任群) Center for Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China Crustal Deformation Research Center Institute of Geology China Seismological Bureau Beijing 100029 China Department of Earth and Space Sciences University of California Los Angeles CA 90095-1567 USA Crustal Deformation Research Center Institute of Geology China Seismological Bureau Beijing 100029 China First Crustal Deformation Monitoring Center China Seismological Bureau Tianjin 300180 China Center for Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China Crustal Deformation Research Center Institute of Geology China Seismological Bureau Beijing 100029 China Institute of Seismology China Seismological Bureau Wuhan 430071 China Crustal Deformation Research Center Institute of Geology China Seismological Bureau Beijing 100029 China

We obtain the preliminary result of crustal deformation velocity field for the Chinese con-tinent by analyzing GPS data from the Crustal Motion Observation Network of China (CMONOC), particularly the data from the regional networks of CMONOC observed in 1999 and 2001. We de-lineate 9 tectonically active blocks and 2 broadly distributed deformation zones out of a denseGPS velocity field, and derive block motion Euler poles for the blocks and their relative motionrates. Our result reveals that there are 3 categories of deformation patterns in the Chinese conti-nent. The first category, associated with the interior of the Tibetan Plateau and the Tianshan oro-genic belt, shows broadly distributed deformation within the regions. The third category, associatedwith the Tarim Basin and the region east of the north-south seismic belt of China, shows block-likemotion, with deformation accommodated along the block boundaries only. The second category, mainly associated with the borderland of the Tibetan Plateau, such as the Qaidam, Qilian, Xining(in eastern Qinghai), and the Diamond-shaped (in western Sichuan and Yunnan) blocks, has thedeformation pattern between the first and the third, i.e. these regions appear to deform block-like,but with smaller sizes and less strength for the blocks. Based on the analysis of the lithosphericstructures and the deformation patterns of the regions above, we come to the inference that thedeformation modes of the Chinese continental crust are mainly controlled by the crustal *** crust of the eastern China and the Tarim Basin is mechanically strong, and its deformationtakes the form of relative motion between rigid blocks. On the other hand, the northward indentation of the Indian plate into the Asia continent has created the uplift of the Tibetan Plateau and the Tianshan Mountains, thickened their crust, and raised the temperature in the crust. The lower crust thus has become ductile, evidenced in low seismic velocity and high elect

关键词： GPS, continental crustal motion, tectonic blocks, significance test.

Resistive plate chambers for muon detection at LHC

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Science China Mathematics 2002年第11期45卷 1446-1451页

作者：叶沿林应军班勇刘洪涛蔡建新朱子美马经国陈陶钱思进 Department of Technical Physics and the DOE Key Laboratory of Heavy Ion Physics Peking University Beijing 100871 China

One resistive plate chamber made of Chinese materials and one Italian resistive platechamber have been test.d in the Gamma Irradiation Facility (GIF) at CERN on a high intensitymuon beam together with a 137Cs source to give a uniform photon background, and simulatingconditions close to those expected for an LHC muon detector. The results are analyzed. Goodspace and time resolutions are obtained which satisfy the future CMS experiment *** detection efficiency is different between two RPCs against a high irradiation background. Thereason is discussed.

关键词： resistive plate chamber, avalanche mode, beam test.

Simultaneous optimal estimates of fixed effects and variance components in the mixed model

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Science China Mathematics 2004年第5期47卷 787-799页

作者： WU Mixia WANG Songgui College of Applied Sciences Beijing University of Technology Beijing 100022 College of Applied Sciences Beijing University of Technology Beijing 100022

For a general linear mixed model with two variance components, a set of simple conditions is obtained, under which, (i) the least squares estimate of the fixed effects and the analysis of variance (ANOVA) estimates of variance components are proved to be uniformly minimum variance unbiased estimates simultaneously; (ii) the exact confidence intervals of the fixed effects and uniformly optimal unbiased test. on variance components are given; (iii) the exact probability expression of ANOVA estimates of variance components taking negative value is obtained.

关键词： linear mixed model, random effect, variance component, minimum variance unbiased estimate,uniformly most powerful unbiased test.

Modeling research in low-medium temperature geothermal field, Tianjin

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Science China Chemistry 2002年第z1期45卷 61-69页

作者：王坤李春华 School of Earth and Space Sciences Peking University Beijing 100871 China Tianjin Geothermal Management Division Tianjin 300191 China

The geothermal reservoir in Tianjin can be divided into two parts: the upper one is the porous medium reservoir in the Tertiary system; the lower one includes the basement reservoir in Lower Paleozoic and Middle-Upper Proterozoic. Hot springs are exposed in the northern mountain and confined geothermal water is imbedded in the southern plain. The geothermal reservoir is incised by several fractures. In recent years, TDS of the geothermal water have gone up along with the production rate increasing, along the eastern fracture zone (Cangdong Fracture and West Baitangkou Fracture). This means that the northern fracture system is the main seepage channel of the deep circulation geothermal water, and the reservoir has good connection in a certain area and definite direction. The isotopic research about hydrogen and carbon chronology indicates that the main recharge period of geothermal water is the Holocene Epoch, the pluvial and chilly period of 20 kaBP. The karst conduits in weathered carbonate rocks of the Proterozoic and Lower Paleozoic and the northeast regional fracture system are the main feeding channels of Tianjin geothermal water. Since the Holocene epoch, the geothermal water stayed at a sealed warm period. The tracer test.in WR45 doublet system shows that the tracer test.is a very effective measure for understanding the reservoir's transport nature and predicting the cooling time and transport velocity during the reinjection. 3-D numerical simulation shows that if the reinjection well keeps a suitable distance from the production well, reinjection will be a highly effective measure to extract more thermal energy from the rock matrix. The cooling of the production well will not be a problem.

关键词： geothermal, model, isotope, reinjection, tracer test.

A test.of conditional heteroscedasticity in time series

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Science China Mathematics 1999年第1期42卷 26-37页

作者：陈敏安鸿志 1. Institute of Systems Science Chinese Academy of Sciences 100080 Beijing China 2. Institute of Applied Mathematics Chinese Academy of Sciences 100080 Beijing China

A new test.of conditional heteroscedasticity for time series is proposed. The new test.ng method is based on a goodness of fit type test.statistics and a Cramer-von Mises type test.statistic. The asymptotic properties... 详细信息

关键词： nonlinear time series model the conditional heteroscedasticity hypothesis test.

A statistical test.on diversity changes of Early and Middle Permian fusulinacean fauna in South China

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Science China Earth Sciences 2005年第7期48卷 978-984页

作者： SHI Yukun YANG Xiangning Department of Earth Sciences Nanjing University Nanjing 210093 China Department of Earth Sciences Nanjing University Nanjing 210093 China

The rarefaction analysis has been conducted to test.the species diversity changes of the Early and Middle Permian fusulinacean fauna in South China. The results reveal that the number of species dramatically increased since the earliest Permian and quickly reached the maximum value in the early Zisongian representing the highest species diversity for the whole Early and Middle Permian. The species diversity stabilized in the plateau through the Zisongian; however, it started to decline in the following Longlinian and sustained a longstanding low level during the mid-Early Permian. With the appearance of new fusulinacean taxa with septulum structures, the number of species raised again in the late-Early Permian, followed by a decline in the Middle Permian Neoschwagerina simplex zone. Although the species diversity increased apparently in the Kuhfengian, it never rebounded back to the same level as in the Early Permian. In the mid-Middle Permian, species diversity began to decrease continuously and led to the disappearance of most fusulinacean species by the end of the Middle Permian.

关键词： South China Permian fusulinacean fauna diversity statistical test.