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Water target based cross-calibration of CBERS-02 CCD camera with MODIS data

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Science china(Technological Sciences) 2005年第S2期48卷 61-71页

作者： TANG Junwu1,2, GU Xingfa2, NIU Shengli1, MA Chaofei1 & MIN Xiangjun3 1. National Satellite Ocean Application service (NSOAS), Beijing 100081, china 2. State Key Laboratory of Remote Sensing Science, Beijing 100010, china 3. china center for Resource Satellite Data and Applications (CRESDA), Beijing 100083, china 1. National Satellite Ocean Application service (NSOAS) 100081 Beijing China 2. State Key Laboratory of Remote Sensing Science 100010 Beijing China 3. china center for Resource Satellite Data and Applications (CRESDA) 100083 Beijing China

In order to make quantitative watercolor sensing with china-Brazil Earth Resources Satellite (CBERS-02) CCD camera, the MODIS data with higher accuracy is used to cross-calibrate the CCD camera over water targets. In homogeneous clear water area, two pairs of images obtained over the same area on the same day by the two sensors are selected. The top-of-atmosphere (TOA) radiances of the multispectral bands of CCD are calculated with the water and aerosol parameters from MODIS based on a water-atmosphere radiative transfer algorithm. The stripes in CCD image that caused by unequal response of the CCD array detectors are firstly removed before making the cross-calibration. The same part of CCD detectors is selected for the calibrations in the two images to eliminate the residual error of destriping and uniformity correction for the focus plane irradiance. It is shown that the calibration results from two different images are consistent. The error of this method is about 5%.

关键词： CBERS-02 CCD MODIS radiometric calibration cross-calibration. DOI: 10.1360/05ze1006

The Process of TiB_2-Cu Composite Phase and Structure Formation during Combustion Synthesis

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Journal of Wuhan University of technology(Materials Science) 2006年第4期21卷 113-116页

作者：徐强 School of Materials Science and Engineering Beijing Insitute of TechnologyBeijing 100081China

The reaction process of combustion synthesis for TiB2 -Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction （ XRD ） analysis, SEM analysis and differential thermal analysis （ DTA ）. The XRD analysis results for the different parts of the quenched specimen show that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3B4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2 phase forms because of the continuous diffusion of B atoms. The formation of TiB2 phase is uot completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages： melting of Cu and Ti , and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases ; large numbers of TiCux intermetallic phases formation and some fine TiB2 particles precipitation ; and the TiB2 particles coarsening and the stable TiB2 and Cu two phases formation in the final product.

关键词： combustion synthesis reaction process TiB2 phase combustion-wave arresting experiment

Theory of truth degrees of propositions in the logic system Ln^＊

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Science in china(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2 & WANG Guojun1,3 1. Institute of Mathematics, Shaanxi Normal University, Xi’an 710062, china 2. School of Sciences, Lanzhou University of technology, Lanzhou 730050, china 3. Research center for Science, Xi’an Jiaotong University, Xi’an 710049, china 1. Institute of Mathematics Shaanxi Normal University Xi’an 710062 China 2. School of Sciences Lanzhou University of Technology Lanzhou 730050 China 3. Research center for Science Xi’an Jiaotong University Xi’an 710049 China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

Study on Environmental Multi-parameter Sensor Based on MEMS

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稀有金属材料与工程 2006年第S3期 377-380页

作者： Hongquan Zhang~(1,3) Tong Zhang~2 Likai Sun~3 Yunbo Shi~3 Jianying Guo~1 (1.Harbin University of Science and technology,Harbin 150080,china) (2.Automobile Electronic Engineering technology Research and Development center,Harbin 150001,china) (3.Northeast Transducer technology Research Institute,Harbin 150001,china)

A new membrane type Al2O3micromachining material is *** develop an environmental multi-parameter detection micro-system,which implements the detection to temperature,humidity,wind speed,and *** test results illustrate that the heat-release unit in micro-system intercross greatly affects other sensing units on the *** study the method of etching process,which formed cavity to reduce the heat exchange efficiency and decrease temperature intercross effect.

关键词： Al2O3 membrane sensing unit environmental multi-parameter microsystem

Three-dimensional Cure Simulation of Stiffened Thermosetting Composite Panels

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Journal of Materials Science & technology 2010年第5期26卷 467-471页

作者： Guangquan Yue,Boming Zhang ,Fuhong Dai and Shanyi Du center for Composite Materials,Harbin Institute of technology,Harbin 150080,china [a] center for Composite Materials Harbin Institute of technology Harbin 150080 china

Stiffened thermosetting composite panels were fabricated with co-curing *** the co-curing processing,the temperature distribution in the composite panels was *** investigation into the threedimensional cure simulation of T-shape stiffened thermosetting composite panels was *** tools and locating tools were considered in the cure *** distribution in the composites was predicted as a function of the autoclave temperature history.A nonlinear transient heat transfer finite element model was developed to simulate the curing process of stiffened thermosetting composite *** a simulation example was presented to demonstrate the use of the present finite element procedure for analyzing composite curing *** glass/polyester structure was investigated to provide insight into the nonuniform cure process and the effect of flexible tools and locating tools on temperature *** gradient in the intersection between the skin and the flange was shown to be strongly dependent on the structure of the flexible tools and the thickness of the skin.

关键词： Thermosetting composite Stiffened panels Co-curing Numerical simulation

The Performance Analysis of Traffic Channel Coding in Digital Trunking System

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Journal of Systems Engineering and Electronics 2001年第2期12卷 30-35页

作者： Tan Xuezhi, Su Min & Zhang Naitong Communication Research center of Harbin Institute of technology, 150001, P R china Communication Research center of Harbin Institute of technology 150001 P.R. China

The encoding and decoding processes of traffic channel in digital trunking system are studied. On the basis of computer simulation, the BER (bit error ratio) with different RCPC decoding step is analyzed. As a result, the optimal RCPC decoding step is provided, which gives essential theoretical evidences for the implementation of digital trunking system.

关键词： Bit error rate Communication channels (information theory) Quadrature phase shift keying Signal encoding Telecommunication traffic

Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve

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Science china(Technological Sciences) 2010年第4期53卷 1082-1087页

作者： CUI Peng,LI Jie & LIU DeSheng Maglev Engineering center,National University of Defense technology,Changsha 410073,china 1. Maglev Engineering center National University of Defense Technology Changsha 410073 China

Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this *** magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube *** to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was *** results provide a theoretical reference for the design of maglev train.

关键词： low-speed maglev train curve flux tube carrying capacity

Reflection of regular and irregular waves from a partially perforated caisson breakwater with a rock-filled core

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Acta Oceanologica Sinica 2007年第3期26卷 129-141页

作者： LIU Yong1, LI Yucheng 1, 2, TENG Bin1, MA Baolian3 1.State Key Laboratory of Coastal and Offshore Engineering, Dalian University of technology, Dalian 116024, china 2.R&D center for Civil Engineering technology, Dalian University, Dalian 116622, china 3.Tianjin Maritime Safety Administration, Tianjin 300456, china State Key Laboratory of Coastal and Offshore Engineering Dalian Universityof Technology Dalian 116024 China

The reflection of regular and irregular waves from a partially perforated caisson breakwater with a rock-filled core is examined. The present mathematical model is developed by means of the matched eigenfunction method. Numerical results of the present model are compared with the experimental data of different researchers. Numerical examples are given to examine the effect of rock fill on the reflection coefficient. The differences between regular and irregular waves are also investigated by means of theoretical and experimental results. It is found that the minimum reflection coefficient of irregular waves is larger than that of corresponding regular waves, but the contrary is the case for the maximum reflection coefficient.

关键词： reflection coefficient regular waves irregular waves partially perforated caisson rock fill

INTEGRATED APPROACH TO ASSEMBLY SEQUENCE PLANNING OF C0MPLEX PRODUCTS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 181-184页

作者： Wang Junfeng Liu Jihong Zhong Yifang CAD center,Huazhong University of Science and technology,Wuhan 430074, china CAD center Huazhong University of Science and Technology Wuhan 430074

Assembly sequence planning will be more difficult due to the increasingcomplexity of products. An integrated approach to assembly sequence planning of complex productsapplying de-composition-planning-combination strategy is presented. First, an assembly is decomposedinto a hierarchical structure using an assembly structure representation based on connectors. Then,an assembly planning system is used to generate the sequences that are locally optimal for eachleaf partition hi the structure hierarchy. By combining the local sequences systematically in abottom-up manner and choosing suitable ones from the merged sequences, the assembly sequence of eachparent structure including the whole assembly is generated. An integrated system has beencompleted. A complex product is given to illustrate the feasibility and the practicality of theapproach.

关键词： Assembly sequence planning Assembly decomposition Structure hierarchy Sequence combination