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Rare Metals 2011年第2期30卷 160-165页

作者： RU Qiang PENG Wei ZHANG Zhiwen HU Shejun LI Yanling laboratory of quantum {2. technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

The physical characters and electrochemical properties of various phases in a Sn-Zn electrode, such as formation energy, plateau potential, specific capacity, as well as volume expansion, were calculated by the first-principles plane-wave pseudo-potential method based on the den- sity functional theory. Sn-Zn films were also deposited on copper foils by an electroless plating technique. The actual composition and chemical characters were explored by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, plasma atomic emission spectrometry （ICP）, and constant current charge/discharge measurements （CC）. The results show that separation phases with tin and zinc including a small quantity of Cu6Sn5 phase were obtained, the initial lithium insertion capacity of the Sn-Zn film was 661 mAh/g, and obvious potential pla- teaus of about 0.4 V and 0.7 V were displayed, which is in accordance with the results of theoretical calculations. The capacity of the Sn-Zn film decreased seriously with the increase of cycle number.

关键词： lithium batteries electrochemical electrodes tin alloys first-principles calculations

Data fusion for target tracking in wireless sensor networks using quantized innovations and Kalman filtering

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science china({2. sciences) 2012年第3期55卷 530-544页

作者： XU Jian1,2., LI JianXun1,2.& XU Sheng3 1Department of Automation, science and technology on Avionics Integration {2., Shanghai Jiao Tong University, Shanghai 2.02.0, china 2.epartment of Automation, System Control and information Processing, Ministry of Education of china, Shanghai Jiao Tong University, Shanghai 2.02.0, china 3School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 2.02.0, china 1. Department of Automation Science and Technology on Avionics Integration Laboratory Shanghai Jiao Tong University Shanghai 200240 China2. Department of Automation System Control and Information Processing Ministry of Education of China Shanghai Jiao Tong University Shanghai 200240 China3. School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

A novel networked data-fusion method is developed for the target tracking in wireless sensor networks (WSNs). Specifically, this paper investigates data fusion scheme under the communication constraint between the fusion center and each sensor. Such a message constraint is motivated by the bandwidth limitation of the communication links, fusion center, and by the limited power budget of local sensors. In the proposed scheme, each sensor collects one noise-corrupted sample, performs a quantizing operation, and transmits quantized message to the fusion center. Then the fusion center combines the received quantized messages to produce a final estimate. The novel data-fusion method is based on the quantized measurement innovations and decentralized Kalman filtering (DKF) with feedback. For the proposed algorithm, the performance analysis of the estimation precision is provided. Finally, Monte Carlo simulations show the effectiveness of the proposed scheme.

关键词： data fusion target tracking limited bandwidth quantized innovation Kalman filtering

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural science:Materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( State Key laboratory of Earthquake Dynamics, Institute of Geology, china Earthquake Administration, {2. 10002., china State Key laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of sciences, {2. 100080, china School of Mathematics and Computational science, Zhongshan University, Guangzhou 5102.5, china center for Analysis and Prediction, china Seismological Bureau, {2. 100036, china Quakes, Department of Earth science, University of Queensland, Brishbane, Austrialia) State Key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China. State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China. School of Mathematics and Computational science Zhongshan University Guangzhou 510275 China. center for Analysis and Prediction China Seismological Bureau Beijing 100036 China. Quakes Department of Earth Science University of Queensland Brishbane Austrialia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

information flow and controlling in regularization inversion of quantitative remote sensing

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science china Earth sciences 2005年第1期48卷 74-83页

作者： YANG Hua, XU Wangli, ZHAO Hongrui, CHEN Xue & WANG Jindi Research center for Remote Sensing and GIS, School of Geography, beijing Normal University, State Key {2. of Remote Sensing science, beijing Key {2. for Remote Sensing of Environment and Digital Cities, beijing 100875, china Department of Mathematics, beijing Normal University, beijing 100875, china 1. Research center for Remote Sensing and GIS School of Geography Beijing Normal University State Key Laboratory of Remote Sensing Science Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities 100875 Beijing China 2. Department of Mathematics Beijing Normal University 100875 Beijing China

In order to minimize uncertainty of the inversed parameters to the largest extent by making full use of the limited information in remote sensing data, it is necessary to understand what the information flow in quantitative remote sensing model inversion is, thus control the information flow. Aiming at this, the paper takes the linear kernel-driven model inversion as an example. At first, the information flow in different inversion methods is calculated and analyzed, then the effect of information flow controlled by multi-stage inversion strategy is studied, finally, an information matrix based on USM is defined to control information flow in inversion. It shows that using Shannon entropy decrease of the inversed parameters can express information flow more properly. Changing the weight of a priori knowledge in inversion or fixing parameters and partitioning datasets in multi-stage inversion strategy can control information flow. In regularization inversion of remote sensing, information matrix based on USM may be a better tool for quantitatively controlling information flow.

关键词： regularization inversion, information flow, Shannon entropy decrease, information matrix.

Lithosphere types in North china:Evidence from geology and geophysics

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science china Earth sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological sciences, beijing 100037,{2. 2. Development and Research center,{2. Geological Survey, beijing 100037,{2. 3.{2. University of Geosciences, beijing 100083,{2. 4.{2. University of Geosciences, Wuhan 430074,{2. 5. information center of Ministry of Land and Resources, beijing 100812.{2. 6. Institute of Geology, State Seismological Bureau, beijing 10002.,{2. 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research center China Geological Survey 100037 Beijing China 3. china University of Geosciences 100083 Beijing China 4. china University of Geosciences 430074 Wuhan China 5. information center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

ON THE SECOND GREEDY WEIGHT FOR LINEAR CODES SATISFYING THE FULLRANK CONDITION

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Journal of Systems science & Complexity 2005年第1期18卷 55-66页

作者： CHENWende KLOVETorleiv laboratoryofSystemsandControlandcenterof{2.Security AcademyofMathematicsandSystemsScienceChineseAcademyofSciencesBeijing100080China DepartmentofInforrnatics UniversityofBergenBergenHighTechnologyCenterN-5020BergenNorway

The maximum of g2.d2.for linear [n, k, d; q] codes C is studied. Here d2.is the smallest size of the support of 2.dimensional subcodes of C and g2.is the smallest size of the support of 2.dimensional subcodes of C which contains a codeword of weight d. The extra cost to the greedy adversary to get two symbols of information using some algorithm is g2.d2. For codes satisfying the fullrank condition of general dimensions, upper bounds on the maximum of g2.d2.are given. Under some condition we have got code C where g2.d2.reaches the upper bound.

关键词： greedy weight linear code bounds

Limitation of fault-sealing and its control on hydrocarbon accumulation——An example from the Laoyemiao Oilfi eld of the Nanpu Sag

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Petroleum science 2008年第4期5卷 295-301页

作者： Jiang Zhenxue Dong Yuexia Li Hongyi Liu Luofu Liu Guangdi Li Xiaoying Basin and Reservoir Research center China University of Petroleum Beijing 102249 China State Key laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Research Institute of Exploration and Development Jidong Oilfield PetroChina Tangshan Hebei 063004 China School of Resources and information technology China University of Petroleum Beijing 102249 China

Based on previous studies on the internal structures of fault belts, the fault belts in the Laoyemiao Oilfield of the Nanpu Sag can be divided into three units, a crushed zone, an upper induced fracture zone and a lower induced fracture zone according to the log response characteristics. The upper induced fracture zone is characterized by the development of pervasive fractures and has a poor sealing or non-sealing capability. It therefore can act as pathways for hydrocarbon migration. The lower induced fracture zone consists of fewer fractures and has limited sealing capability. The crushed zone has a good sealing capability comparable to mudstone and can thus prevent lateral migration of fluid. Through physical modeling and comparing laboratory data with calculated data of oil column heights of traps sealed by faults, it is concluded that the fault-sealing capability for oil and gas is limited. When the oil column height reaches a threshold, oil will spill over from the top of reservoir along the lower induced fracture zone under the action of buoyancy, and the size of reservoir will remain unchanged. Analysis of the formation mechanisms of the fault-sealed reservoirs in the Nanpu Sag indicated that the charging sequence of oil and gas in the reservoir was from lower formation to upper formation, with the fault playing an important role in oil and gas accumulation. The hydrocarbon potential in reverse fault-sealed traps is much better than that in the consequent fault-sealed traps. The reverse fault-sealed traps are favorable and preferred exploration targets.

关键词： Limitation of fault-sealing fault belt oil column height hydrocarbon accumulation Nanpu Sag

A NOVEL METHOD FOR CHARACTERIZING THE WHOLE PROCESS OF POLYMER GELATION

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Chinese Journal of Polymer science 2001年第4期19卷 335-339页

作者： Qiang Chen Xian-min Zhang Guo-wei Wang Jian Xu State Key laboratory of Polymer Physics & Chemistry, center for Molecular {2., Institute of Chemistry, Chinese Academy of {2.s beijing 100080, china Department of information & Electronic Engineering Zhejiang University, Hangzhou 31002., china Tjanjin Polytechnic University,Tianjin 300160 Chinese Acad Sci Ctr Mol Sci State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China Zhejiang Univ Dept Informat & Elect Engn Hangzhou 310027 Peoples R China

A novel method was established to investigate the gelation process of polymers. The change of refractive index of a polymer system during gelation was determined in situ in a prismatic cell. It can give reliable information on the whole gelation process. The apparatus and the execution of this technique are illustrated and the error is also discussed.

关键词： gelation process in situ technique refractive index

Multi-resolution representation of digital terrain models with terrain features preservation

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science china(Technological sciences) 2008年第S1期51卷 145-154页

作者： LI QingQuan1,WANG Zhi1,2.& YANG BiSheng1 1 State Key laboratory of information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,{2. 2.School of Remote Sensing and information Engineering,Wuhan University,Wuhan 430079,{2. 1. State Key laboratory of information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China2. School of Remote Sensing and Information Engineering Wuhan University Wuhan 430079 China

multi-resolution TIN model is an important issue in the contexts of visu-alization,virtual reality (VR),and geographic information systems (GIS). This paper proposes a new method for constructing multi-resolution TIN models with multi-scale topographic features preservation. The proposed method is driven by a half-edge collapse operation in a greedy framework and employs a new quadric error metric to efficiently measure geometric errors. We define topographic features in a multi-scale manner using a center-surround operator on Gaussian-weighted mean curvatures. Experimental results demonstrate that the proposed method performs better than previous methods in terms of topographic features preservation,and is able to achieve multi-resolution TIN models with a higher accuracy.

关键词： digital terrain models level of detail differential-geometry quadric error metrics topographic feature

Quantifying the effectiveness of SiO_2.Au light trapping nanoshells for thin film poly-Si solar cells

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science china(Technological sciences) 2010年第8期53卷 2228-2231页

作者： BAI YiMing 1 ,WANG Jun 2.,CHEN NuoFu 1,3 ,YAO JianXi 1 ,YIN ZhiGang 3 ,ZHANG Han 3 , ZHANG XingWang 3 ,HUANG TianMao 3 ,WANG YanShuo 3 &YANG XiaoLi 3 1School of Renewable Energy Engineering,North china Electric Power University,beijing 102.06,{2. 2.national Engineering Research center for Optoelectronic Devices,Institute of Semiconductors, Chinese Academy of sciences,PO Box 912.beijing 100083,{2. 3 Key laboratory of Semiconductor Materials science,Institute of Semiconductors, Chinese Academy of sciences,PO Box 912.beijing 100083,{2. 1. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China2. National Engineering Research Center for Optoelectronic Devices Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China3. Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China

In order to enhance light absorption of thin film poly-crystalline silicon(TF poly-Si)solar cells over a broad spectral range, and quantify the effectiveness of nanoshell light trapping structure over the full solar spectrum in theory,the effective photon trapping flux(EPTF)and effective photon trapping efficiency(EPTE)were firstly proposed by considering both the external quantum efficiency of TF poly-Si solar cell and scattering properties of light trapping *** EPTF,EPTE and scattering spectrum exhibit different behaviors depending on the geometric size and density of nanoshells that form the light trapping *** an optimum size and density of SiO2.Au nanoshell light trapping layer,the EPTE could reach up to 40%due to the enhancement of light trapping over a broad spectral range,especially from 500 to 800 nm.

关键词： thin film poly-crystalline silicon surface plasmons SiO2.Au nanoshell