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Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical Information Science and Technology, school of Science, Northwestern Polytechnical University, Xi’an 710072. china 2. school of Science, Xi’an Jiaotong University, Xi’an 71004., china 1. Institute of Optical Information Science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. school of Science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

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Aridity/humidity status of land surface in china during the last three decades

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Science china Earth Sciences 2005年第9期48卷 1510-1518页

作者： WU Shaohong1, YIN Yunhe1,2. ZHENG Du1 & YANG Qinye1 1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101, china 2. graduate {2. of the CAS, Beijing 100039, china 1. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences (CAS) 100101 Beijing China 2. graduate school of the CAS 100039 Beijing China

To clarify aridity/humidity status of land surface is helpful for studying environmental background and regional differences, seeking causes of environmental change, and providing a scientific basis for researches on climate change in the future. In this paper, the authors calcu- lated potential evapotranspiration of china using data from 616 meteorological stations during the period of 1971―2.00 with the Penman-Monteith model recommanded by FAO in 1998. Vy- sothkii’s model was used to calculate aridity/humidity index. Then the calculated results of sta- tions were interpolated to land surface using ArcGIS. Results show that the annual average po- tential evapotranspiration is 4.0―1500 mm in the whole country, 600―800 mm in most parts of it; and 350―14.0 mm in growing season (April―Octobor), which is nearly 2.0 mm less than the annual average. According to the aridity/humidity indexes of 1.0, 1.5 and 4.0, the aridity/humidity status is categorized to four types, namely, humid, subhumid, semiarid and arid. A majority of stations (76%) are more humid in growing season than the annual average. Results of com- prisons between the distribution map of aridity/humidity index with that of precipitation and vegetation indicate a good consistence of aridity/humidity status with natural environment. Therefore potential evapotranspiration calculated with modified FAO’s Penman-Monteith model in combination with aridity/humidity index that considers water balance can more reasonably explain the actual land surface aridity/humidity status of china.

关键词： potential evapotranspiration, aridity/humidity status, land surface, regional differences, Penman-Monteith.

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Research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural Science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2.**, WU Xingfang~1, GU Weichao~2. CHEN Guangliang~2. FENG Wenran~2. NIU Erwu~2. LI Li~2. L Guohua~2. CHEN Huan~2. FAN Songhua~2. LIU Chizi~2.and YANG Size~2.1. school of Material Science and Engineering, University of Science and Technology Beijing, Beijing 100083, china 2. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china) school of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

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Integrated Standardization and Systems Engineering Management

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厦门大学学报（自然科学版） 2002年第S1期41卷 235-236页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2. YU Xin-qi 3, RUAN Xin 4.(1. Ordance Institute of General Equipment Department, Shiji azhuang 050000, china 2. graduate {2. of Chinese Academic of Science, Beijing 10004.0} china 3. East china University of Science and Technology, Shanghai 2.02.2. china 4. Meterology Bureau of Hebei Province, Shijiazhuang 05002., china)

Integrated standardization is one of the fundamenta l forms of modern standardization. It is the combination of system science and the content of standardization. The development of system science has provided theo retic foundation and precondition for integrated standardization. The relevant r esearch on integrated standardization and system engineering illustrate that int egrated standardization is a advanced method which presented with the developmen t of modern science and technology . Integrated standardization treat the re levant factors of standardization as a system, and wholly standarlize the factor s in order to reach the best level of technology and quality. Integrated standardization is a large system engineering. In modern industr y the contact among different departments is being constantly enlarged and t he complexity of product is being constantly increased. This situation demands s trict correspond and united request in all the following aspects: raw mate rial, organs, fittings, technical measures of production, preparation for produc tion, ways of organizing the production. The traditional measure which establish the respective standard separately must be replaced by multi-spetialty standa rdization in large spectrum. The current situation and the development of syste m science has provided theoretic foundation and precondition for this kind of st andardization. Product or project can be managed with system engineering of proj ect, while the correspond standardization can be managed with system engineering of standardization. Integrated standardization virtually is system engineering of standardization, w hich use the theory to deal with the problem about standardization . This thesis included 3 chapters: 1. the brief summary of integrated standardization and sys tem engineering management in the development of type in foreign countries; 2. t he current situation and existing problems in the development of products; 3. ho w to organize and actualiz

关键词： integrated standardization system engineering ma nagement

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Study of Product Quality Information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept

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厦门大学学报（自然科学版） 2002年第S1期41卷 234-235页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2. YU Xin-qi 2. RUAN Xin 3 (1. Ordance Institute of General Equipment Department, Shijiazhuang 05 0000, china 2. {4. {2. of Chinese Academic of Science, Beijing 10004.0} china 3. East china University of Science and Technology, Shanghai 2.02.2. china 4. Meterology Bureau of Hebei Province, Shijiazhuang 05002., china)

The 2.th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of china and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:*** type of qua

关键词： product guality information decision-making sup port system of management of guality information people’s guality concept

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Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science china(Technological Sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2. WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, china 2. graduate {2., Chinese Academy of Sciences, Beijing 100039, china Correspondence should be addressed to Jing Xingjian 1. Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences 10016 Shenyang China 2. graduate school Chinese Academy of Sciences 10039 Beijing China

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robot’s dynamic constraints. The direction of the coordinating force can be determiend on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

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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, china 2. Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080, china 3. Institute of Software, Chinese Academy of Sciences, Beijing 100080, china 4. graduate University of Chinese Academy of Sciences, Beijing 10004., china 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.

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Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua Science and Technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2., Yuanyuan Dan 3 , Sen Xu 4.1. school of Computer Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 2.2.03,{4. 2. Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, IA 52.4.0} USA 3. school of Biology and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 2.2.03,{4. 4. school of Information Engineering, Yancheng Institute of Technology, Yancheng 2.4.51,{4. school of Computer Science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

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Electronic Structure of Doped Trans-Polyacetylene

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2. Zhuang Wei 2. Wang Jun 2.1. Wuhan University Journals Press,Wuhan 4.0072.Hubei,{4. 2. school of Physics and Technology, Wuhan University, Wuhan 4.0072.Hubei,{4. Wuhan University Journals Press Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Wuhan University School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Wuhan University School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C2.H2.)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2.method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

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A novel algorithm of artificial immune system for high-dimensional function numerical optimization

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Progress in Natural Science:Materials International 2005年第5期15卷 463-471页

作者： DU Haifeng 1,2.*, GONG Maoguo1, JIAO Licheng1 and LIU Ruochen1(1. Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing, Xidian University, Xi'an 710071, china 2. school of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 71004., china) Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing Xidian University Xi''an 710071 China school of Mechanical Engineering Xi''an Jiaotong University Xi''an 710049 China

Based on the clonal selection theory and immune memory theory, a novel artificial immune system algorithm, immune memory clonal programming algorithm (IMCPA), is put forward. Using the theorem of Markov chain, it is proved that IMCPA is convergent. Compared with some other evolutionary programming algorithms (like Breeder genetic algorithm), IMCPA is shown to be an evolutionary strategy capable of solving complex machine learning tasks, like high-dimensional function optimization, which maintains the diversity of the population and avoids prematurity to some extent, and has a higher convergence speed.

关键词： clonal selection immune memory artificial immune system evolutionary algorithms Markov chain.

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