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Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2. ZHANG Yin-ling1, 2. WANG Fei 1 ,2. ZHANG Zhen-hui 3. GUO Yu-xiang1, 2.1. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic University, Jiaozuo 454003. china 2. S{2. of Surveying and land information engineering, Henan Polytechnic University, Jiaozuo 454003. china 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 2.6041, china Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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science china({2. sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2.& YANG LuXi 2.1 College of Communication and information {3.,Nanjing University of Posts and Telecommunications,Nanjing 2.0003.{2. 2.School of information science and {3.,southeast University,Nanjing 2.0096,{2. 1. College of Communication and information engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Optimal guaranteed cost control for fuzzy descriptor systems with time-varying delay

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Journal of Systems engineering and Electronics 2008年第3期19卷 584-591页

作者： Tian Weihua1,2.& Zhang Huaguang3.1. School of information {2. and engineering, Northeastern Univ., Shenyang 110004, P. R. china 2. Dept. of Automatic Control, Shenyang Inst. of engineering, Shenyang 11013., P. R. china 3. School of information {2. and engineering, Northeastern Univ., Shenyang 110004, P. R. china. (Received December 2., 2.06) [a]School of information {2. and {3. Northeastern Univ. Shenyang 110004 P. R. china [b]Dept. of Automatic Control Shenyang Inst. of engineering Shenyang 11013. P. R. china [c]School of {2. {3. and engineering Northeastern Univ. Shenyang 110004 P. R. china

Based on the delay-independent rule, the problem of optimal guaranteed cost control for a class of Takagi-Sugeno （T-S） fuzzy descriptor systems with time-varying delay is studied. A linear quadratic cost function is considered as the performance index of the closed-loop system. Sufficient conditions for the existence of guaranteed cost controllers via state feedback are given in terms of linear matrix inequalities （LMIs）, and the design of an optimal guaranteed cost controller can be reduced to a convex optimization problem. It is shown that the designed controller not only guarantees the asymptotic stability of the closed-loop fuzzy descriptor delay system, but also provides an optimized upper bound of the guaranteed cost. At last, a numerical example is given to illustrate the effectiveness of the proposed method and the perfect performance of the optimal guaranteed cost controller.

关键词： fuzzy descriptor systems optimal guaranteed cost control time-varying delay linear matrix inequalities (LMIs).

Two possible mechanisms for vortex self-organization

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science china Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological sciences, Beijing 100081, china 2. Department of Space {2. science, Nanjing University of {2. science and Technology, Nanjing 2.0044, china 3. Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china 2. Department of Environmental science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3.1. State Key Laboratory of Tribiology, Tsinghua University, Beijing 100084, china 2. Department of Material {3.s, Changchun University of {3. and Technology, Changchun 13.02., china 3. Faculty of information and engineering Systems, City Campus, Leeds LS1 3.E, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of Material sciences Changchun University of Science and Technology Changchun 130021 China Faculty of information and engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMS) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2. YU Yi-ju3.1. School of Surveying and Landing information {2., Henan Polytechnic University, Jiaozuo 454003. china 2. College of Geoscience and Surveying {2., china University of Mining and Technology, Beijing 100083. china 3. Surveying and Mapping Press, Beijing 100045, china [a] School of Surveying and Landing information {2. Henan Polytechnic University Jiaozuo 454003 China [b] College of Geoscience and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192.mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

A Feedback-Based Web Search Engine

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Wuhan University Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2.3., XU Bao-wen 2.3.4 , ZHOU Xiao-yu 2.3.4 1. Department of Computer {3. and engineering, Nanjing University of Posts and Telecommunications, Nanjing 2.0003. Jiangsu, {2. 2. Department of Computer {3. and engineering, southeast University, Nanjing 2.0096, Jiangsu, {2. 3. Jiangsu Institute of Software Quality, Nanjing 2.0096 Jiangsu, {2. 4. The State Key Laboratory of Software engineering, Wuhan University, Wuhan 43.072. Hubei, {2. Department of Computer science and engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 3.1. 13..4 Foundation item: Supported by the National Natural {3. Fundation of china (603.3.66). National Grand Fundamental Research 973.Program of china (2.02.B3.2.0). Opening Foundation of State Key Laboratory of Software engineering in Wuhan University, Opening Foundation of Jiangsu Key Laboratory of Computer information Processing Technology in Soochow UniversityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

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, School of Geography, Beijing Normal University, Beijing 100875, china 2. State Key Laboratory of Remote Sensing {2., 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.

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2. Wu Yigen3.and Guo Shengli3.1. College of Life sciences, Zhejiang University, Hangzhou 3.0058, china 2. Imaging Department of Tongji Hospital of Tongji University, Shanghai 2.0065, china 3. College of Mathematics and Physics, Nanjing University of information science and Technology, Nanjing 2.0044, china) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging Department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.