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Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural Science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. school of Application Science and Technology, Harbin University of Science and Technology, Harbin 150080, china 2. Department of Precision Instruments, Tsinghua University, {2. 100084. china) school of Application Science and Technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Evaluation of the Interfacial Adhesion between Brittle Coating and Ductile Substrate by Cross-Sectional Indention

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材料热处理学报 2004年第5B期25卷 1187-1190页

作者： SUJian-yu ZHANGKun CHENGuang-nan InstituteofMechanics ChineseAcademyofSciencesBeijingChina／／GraduateSchooloftheChineseAcademyofSciencesBeijingChina InstituteofMechanics ChineseAcademyofSciencesBeijingChina

The cross-sectional indentation method is extended to evaluate the interfacial adhesion between brittle coating and ductile substrate. The experimental results on electroplated chromium coating/steel substrate show that the interfacial separation occurs due to the edge chipping of brittle coating. The corresponding models are established to elucidate interfacial separation processes. This work further highlights the advantages and potential of this novel indentation method.

关键词：分界面附着刻痕可锻衬底应力涂层铬钢

Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3,JIN ZHi1,2.& WU Budan1,4.1. Academy of Mathematics and Systems Science, Chinese Academy of sciences, beijing 100080,{2. 2. Institute of Computing Technology, Chinese Academy of sciences, beijing 100080,{2. 3. Institute of Software, Chinese Academy of sciences, beijing 100080,{2. 4. Graduate University of Chinese Academy of sciences, beijing 10004.,{2. 1. Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China 3. Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Institute of Computing Technology Chinese Academy of Sciences Bejing 100080 China 4. Graduate University of Chinese Academy of sciences Beijing 100049 China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. Nanjing Institute of Geography & Limnology, Chinese Academy of sciences, Nanjing 2.0008, china 2. Graduate {2. of the Chinese Academy of sciences, beijing 100039, china 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. Graduate school of the Chinese Academy of sciences Beijing 100039 China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04.and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2.03, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2.03, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04.to1.95 m with a mean value of 1.35±0.2. m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4. 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 4.0 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4. YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, {4. of Geography, beijing Normal University, beijing 100875, china 2. State Key Laboratory of Remote Sensing Science, beijing 100875, china 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china 4. Department of Information Management, College of Information and Electronic Engineering, china Agricultural University, beijing 100083, china 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2. ZHAO Ming-yang 2.(1. Graduate school of the Chinese Academy of sciences,{2. , china 2. Robotics Laboratory, Shenyang Institute of Automation, Chinese Academy of S ciences, Shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. Researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control

Estimation methods of eco-environmental water requirements: Case study

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Science china Earth sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2. CUI Baoshan1 & LIU Jingling 1. school of Environment, beijing Normal University, beijing 100875,{4. 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, beijing 100875,{4. 1. school of Environment Beijing Normal University 100875 Beijing China 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control 100875 Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2.10, 2.30, 2.50) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84.1010m3 to 1.02.1011m3, the suitable water requirement ranges from 6.4.×1010m3 to 1.78×1011m3, the water shortage ranges from 9.1×109m3 to 2.16×1010m3 under the minimum water requirement, and it is from 3.07×1010m3 to 7.53×1010m3 under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2.10, 2.30, 2.50) are 4.4.×1010m3?1.73×1011m3, 5.99×10m3?2.09×1011m3, and 7.4.×1010m3?2.52.1011m3, respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

Source time-function as discriminant using empirical Green's function

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Science china Earth sciences 2005年第12期48卷 2118-2122页

作者： HE Yongfeng1,2.& CHEN Xiaofei1 1. Department of Geophysics, school of Earth & Space sciences, Peking University, {2. 100871,{4. 2. North-West Institute of Nuclear Technology, Xi’an 71002.,{4. 1. Department of Geophysics School of Earth & Space Sciences Peking University 100871 Beijing China 2. North-West Institute of Nuclear Technology 710024 Xi’an China

The source mechanism of underground nuclear explosions is remarkably different from that of earthquakes in both spatial radiation pattern and source time-function (STF). Small underground nuclear explosions can be used as empirical Green’s functions (EGF) to isolate the source-time spectrum of a large suspected earthquake occurred in a Nuclear Test Site (target area) by the spectral division method. As this study shows, with high-quality data, the quotient spectrum can be transformed to the time domain, yielding the apparent far-field source-time function of the large suspected event. The relative source time-function (RSTF) of a nuclear ex-plosion is usually a simple pulse with a duration of about 1 s., while an earthquake’s is more complicated with a series of pulses and a longer duration. The RSTF can be used as a nice dis-criminant to distinguish the nature earthquakes from underground nuclear explosions in target areas.

关键词： target-area, empirical Green's function, RSTF.

Fluorescence fluctuation spectroscopy and its artifacts:simulations and tests

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 336-344页

作者： MENG Fanbo 1 , CHEN Bo 1 , LIU Guang 1 , DING Jianying 1 & MA Hui 2.1 1. Department of Physics and Key Laboratory of Atomic and Molecular Nano sciences, Ministry of Educa- tion, Tsinghua University, beijing 100084.{2. 2. Graduate school at Shenzhen, Tsinghua University, Shenzhen 518055,{2. 1. Department of Physics and Key Laboratory of Atomic and Molecular Nano sciences Ministry of Education Tsinghua University 100084 Beijing China 2. Graduate school at Shenzhen Tsinghua University 518055 Shenzhen China

Fluorescence fluctuation spectroscopy (FFS) technique is capable of monitoring changes in concentration, mass, size and structure of fluorescent-labeled bio-molecules in microscopic volume and is suitable for measuring biological interactions in living cells. FFS data may be affected by many experimental factors in complicated biological systems. Using a Monte Carlo approach, we generate fluorescence fluctuation data for different experimental systems. This approach helps to separate the contributions by different experimental factors in a complicated fluorescence fluctuation spectrum. It also helps to validate new theoretical models and new fitting formulations. We describe the algorithm of the simulation program and tests on its statistical performance. The program is then used successfully to study the effects of several experimental factors on FFS detection.

关键词： fluorescence fluctuation spectroscopy, fluorescence correlation spectroscopy, Monte Carlo simulation.