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On the Restricting Factors & System Arrangements of Chinese Land Tenure Marketization

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Journal of Northeast Agricultural university(English Edition) 2003年第2期10卷 166-172页

作者： YU Peng-yi,ZHANG Wei-dong(Business school of Huazhong university of Science and {2. wuhan,hubei,430074,PRC) Business school of Huazhong university of Science and {2. wuhan Hubei430074PRC

As a general rule of Economics of Development,economic growth and development require rational institution *** *** a main institution factor in agricultural development,closely relates to the reform of Chinese *** on the relevant theories of Economics of Institution and Economics of Development,and combined with the marketization process of Chinese Land Tenure of Property Rights,the article studied the effects of institutional factors and put forward some choices in the development of agriculture,which is of both significant and practical importance.

关键词： land tenure of property rights institution choice rural reform

New Die Leveling Method Based on Passive Auto-focus in Automatic High Precision Flip-chip Bonders

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New Die Leveling Method Based on Passive Auto-focus in Autom...

Spotlight SAR sparse sampling and imaging method based on compressive sensing

2.d International Symposium on Advanced Optical Manufacturing and Testing Technologies

作者： Zhong Fei Zhong Ming HeTao Zhong Yunin Shi Tielin (school of Mechanical Science & Engineering. Huazhong university of Science & {2. wuhan 430074 china school of Mechanical Engineering hubei university of {2.. wuhan 430068 china)

＜正＞A new die leveling method based on passive auto-focus in automatic high precision flip-chip bonder is presented in this paper and is used in our project. Automatic high precision flip-chip bonders ,in which the alignment system are the one of the key components, are used for die placement and die bonding in IC, MEMS and MOEMS assembly process. The alignment is divided into traverse alignment and longitudinal alignment-focusing alignment. Simultaneously, the die must be parallel to the substrate before being bonded for well-proportioned force on bumps. Die leveling and, sometimes, auto-focus arc completed by aided complex optical devices other than imaging system in the bonders, where several different components must be alternated orderly in time axis. Firstly, just a set of imaging optical component, which used to merely complete traverse alignment and now could be used for the all three procedures, is designed and adopted in our method. Auto-focus is completed by estimating the sharpness of images and leveling by focusing for several locations covering the feature. As a result, the complexity of system is reduced;the resolution of system is also satisfying;time-consuming can be compensated to some extent by high-speed processors and algorithms. The optical system consists of a dual direction microscope system （with two 10X objectives）, which can be inserted between die and substrate to provide visual images of both die and substrate. A 1/2. CCD （cell size, 8.6um×8.3um） receives alternately images of the die and substrate by controlling the illumination （blue coaxial light）. The resolving power of the optical system is up to 1.7um and the depth of view is not beyond 8um. Secondly, passive auto-focus method is discussed as an emphasis. The method determines the distance to the object by computer analysis of the image itself. Changing focal distance or the object distance is then responded to obtain the sharpest image. These two steps above are the sharpness calcu

关键词： alignment die leveling passive auto-focus sharpness calculation feature recognition

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Science china(Information Sciences) 2012年第8期55卷 1816-1829页

作者： XU HuaPing1,YOU YaNan1,LI ChunSheng1&ZHANG LvQian2.1S chool of Electronics and Information Engineering,Beihang university,Beijing 100191,china 2. hinese Academy of Engineering,Beijing 100088,china 1. school of Electronics and Information Engineering Beihang University Beijing 100191 China2. Chinese Academy of Engineering Beijing 100088 China

Spotlight synthetic aperture radar(SAR)emits a chirp signal and the echo bandwidth can be reduced through dechirp processing,where the A/D sampling rate decreases accordingly at the *** sensing allows the compressible signal to be reconstructed with a high probability using only a few samples by solving a linear program *** paper presents a novel signal sampling and imaging method for application to spotlight SAR based on compressive *** signal is randomly sampled after dechirp processing to form a low-dimensional sample set,and the dechirp basis is imported to reconstruct the dechirp *** pursuit(MP)is used as a reconstruction *** reconstructed signal uses polar format algorithm(PFA)for *** our novel mechanism increases the system complexity to an extent,the data storage requirements can be compressed *** simulations verify the feasibility and accuracy of spotlight SAR signal processing via compressive sensing,and the method still obtains acceptable imaging results with 10%of the original echo data.

关键词： spotlight SAR dechirp processing compressive sensing radar signal processing

A New Method for Fractal Dimension Determination by STM at Nanometer Scale

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 64-68页

作者： Qikai Li Yue Zhang Wuyang Chu Chen Wang Chunli Bai (Applied Science school. university of Science and {2. Beijing, Beijing 100083. china)(Chemical Institute, Chinese Academy of Science, Beijing 100080. china) Applied Science school University of Science and Technology Beijing Beijing 100083 China Chemical Institute Chinese Academy of Science Beijing 100080 China

A new method for determining the fractal dimension by STM at nanomeler scale has been ***- Mandelbrot fractal curves were used to verify the accuracy and reliability. The Computer simulation showed that fractal dimen- sion obtained with this method generally outran the traditional yard method. The new method has been applied to the fractal dimension determination of the fractures of Ti3Al and Ti-2.Al-11Nb alloys. The results show that the fractal dimension of Ti-2.Al-11Nb alloy is higher than that of Ti3Al, and it varies with the crark extending orientation.

关键词： fractal dimension STM nanometer scale Ti-Al alloy

3D-QSAR study of 2.(S)-camptothecin analogs

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Acta Pharmacologica Sinica 2007年第2期28卷 307-314页

作者： Ai-jun LU~(1,2. Zhen-shan ZHANG~2.Ming-yue ZHENG~2.Han-jun ZOU~2.Xiao-min LUO~2.Hua-liang JIANG~(2.3,4)1 Jiangsu Simcere Pharmaceutical Research Company Ltd,Nanjing 2.0042.china 2.Drug Discovery and Design Center,State Key Lab of Drug Research,Shanghai Institute of Materia Medica,Chinese Academy of Sciences,Shanghai 2.12.3,china 3 {2. of Pharmacy,East china university of Science and technology,Shanghai 2.02.7,china Jiangsu Simcere Pharmaceutical Research Company Ltd Nanjing 210042ChinaDrug Discovery and Design CenterState Key Lab of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Aim:To build up a quantitative structure-activity relationship（QSAR）model of2.（S）-camptothecin（CPT）analogs for the prediction of the activity of new CPTanalogs for drug ***:A training set of 43 structurally diverse CPTanalogs which were inhibitors of topoisomerase I were used to construct a quan-titative structure-activity relationship model with a comparative molecular fieldanalysis（CoMFA）.The QSAR model was optimized using partial least squares（PLS）analysis.A test set of 10 compounds was evaluated using the ***:The CoMFA model was constructed successfully,and a good cross-validated correlation was obtained in which q2.as ***,the analysis ofthe non-cross-validated PLS model in which r2.as 0.935 was built and permitteddemonstrations of high predictability for the activities of the 10 CPT analogs inthe test set selected in ***:The CoMFA model indicated thatbulky negative-charged group at position 9,10 and 11 of CPT would increaseactivity,but excessively increasing bulky group at position 10 is adverse to inhibi-tory activity;substituents that occupy position 7 with the bulky positive groupwill enhance the inhibitive *** model can be used to design new CPTanalogs and understand the mechanism of action.

关键词： comparative molecular field analysis(CoMFA) camptothecin(CPT) topoisomerase I(Top I)

Hamiltonian Formalism of de-Sitter Invariant Special Relativity

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Communications in Theoretical physics 2007年第7期48卷 27-36页

作者： YAN Mu-Lin XIAO Neng-Chao HUANG Wei Interdisciplinary Center for Theoretical Study,university of Science and technology of {2.,Hefei 2.002.,{2.LI Si Department of Mathematics,university of Science and technology of {2.,Hefei 2.002.,{2. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China Department of Mathematics University of Science and Technology of China Hefei 230026 China

The Lagrangian of Einstein's special relativity with universal parameter c(SR_c)is invariant under Poincarétransformation,which preserves Lorentz metric η_μν.The SR_c has been extended to be one which is invariant underde Sitter transformation that preserves so-called Beltrami metric B_(μv).There are two universal parameters,c and R,inthis Special Relativity(denoted as SR_(cR)).The Lagrangian-Hamiltonian formulism of SR_(cR) is formulated in this *** canonic energy,canonic momenta,and 10 Noether charges corresponding to the space-time's,de Sitter symmetryare *** canonical quantization of the mechanics for SR_(CR)-free particle is *** physics related to itis discussed.

关键词： de-Sitter invariance special relativity canonic energy and canonic momenta Beltrami metric

Assessment of heavy metals contamination in soils of Dexing region, Jiangxi Province, china

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Acta Geochimica 2006年第S1期 27-28页

作者： Cuihua CHEN1, Shijun NI2. Binbin HE3, Chengjiang ZHANG2.1 school of Geosciences, Chengdu university of {2., Chengdu 610059, china 2.school of Applied Nuclear Techniques & Automatic Engineering, Chengdu university of {2., Chengdu 610059, china 3 Institute of Geo-Spatial Information Science and {2., university of Electronic Science and {2. of china, Chengdu 610054, china

STABILITY OF TIME VARYING SINGULAR DIFFERENTIAL SYSTEMS WITH DELAY

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Annals of Differential Equations 2008年第4期24卷 484-489页

作者： Zhang Hai1,2. Jiang Wei1 (1. school of Mathematical Sciences, Anhui university, Hefei 2.0039 2. school of Math. and Computation Sci., Anqing Teachers College, Anqing 2.6011, Anhui)

In this paper, stability of time varying singular differential systems with delay is considered. Based on variation formula and Gronwall-Bellman integral inequality, we obtain the exponential estimation of the solution and the sufficient conditions under which the considered system is stable and exponentially asymptotically stable. These results will be very useful to further research on Roust stability and control design of uncertain singular control systems with delay.

关键词： singular differential systems with delay time varying exponential estimation stability

On Decision Support Systems and It’s Application to the Clinical Decisions

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On Decision Support Systems and It’s Application to the Cli...