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Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science China(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4.1 College of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, Beijing Normal university, Beijing 100875, China 2 school of science, Beijing Institute of Education, Beijing 100011, China 3 school of Mathematical sciences, Beijing Normal university, Beijing 100875, China 4.College of information science and Technology, Beijing Normal university, Beijing 100875, China 1. College of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. school of science Beijing Institute of Education Beijing 100011 China 3. school of Mathematical sciences Beijing Normal University Beijing 100875 China 4. College of information science and Technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004. from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

BLIND AND COMPLETE MODELING OF LINEAR SYSTEMS USING THIRD ORDER CUMULANTS

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Journal of Electronics(China) 2007年第5期24卷 649-654页

作者： FU Jian Tan Hongzhou Huang Yihua guangzhou science and Technology Bureau Guangzhou 510032 China school of information science and Technology Sun Yat-Sen University Guangzhou 510275 China

This paper presents a novel approach to structure determination of linear systems along with the choice of system orders and parameters. AutoRegressive （AR）, Moving Average （MA） or AutoRegressive-Moving Average （ARMA） model structure can be extracted blindly from the Third Order Cumulants （TOC） of the system output ts, where the unknown system is driven by an unobservable stationary independent identically distributed （i.i.d.） non-Gaussian signal. By means of the system order recursion, whether the system has an AR structure or has AR part of an ARMA structure is firstly investigated. MA features in the TOC domain is then applied as a threshold to decide if the system is an MA model or has MA part of an ARMA model. Numerical simulations illustrate the generality of the proposed blind structure identification methodology that may serve as a guideline for blind, linear system modeling.

关键词： AutoRegressive-Moving Average (ARMA) models The Third-Order Cumulants (TOC) Blind structure identification Order recursion

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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science China Earth sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, China 2. Institute of Geophysics, China Seismological Bureau, Beijing 100085, China 3. Institute of Deposition Resource, Chinese Academy of Geosciences, Beijing 100037, China 4. school of Exploration and information, China {4. of Geosciences, Beijing 100083, China 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. school of Exploration and information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, China. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

Establishment of the Secure Channel between Broker Nodes in Pub/Sub System

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Wuhan university Journal of Natural sciences 2006年第6期11卷 1441-1444页

作者： ZHU Shuren information science school Guangdong University of Business Studies Guangzhou 510320 Guangdong China

The paper mainly discusses the integrity of the forwarded subscription message guaranteed by secure channel which encrypted in data communication by using data encryption standard （DES） algorithm and chaos code algorithm between broker nodes in the routing process of the contentbased publish/subscribe system. It analyzes the security of the secure channel encrypted with data communication by DES algorithm and chaos code algorithm, and finds out the secure channel can be easily attacked by known plain text. Therefore, the paper proposes the improved algorithm of message encryption and authentication, combining encryption and the generation of the message authentication code together to finish scanning at one time, which enhances both the secure degree and running efficiency. This secure channel system has a certain reference value to the pub/sub system requiring highly communication security.

关键词： publish/subscribe routing algorithm subscription message secure channel data encryption standard (DES)

Anticoagulation property and security of artificial heart valve material

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science China(Technological sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,22, 3, ZHANG Feng2, LI Changrong2, YU Liujiang2, ZHENG Zhihong2, WANG Xi2, JIANG Zhenbin4. CHEN Anqing4.& XU Jingfang3 1. Department of Physics, East China Normal university, Shanghai 200062, China 2. Ion Beam Lab, Shanghai Institute of Mini-system and information, Chinese Academy of sciences,Shanghai 200050, China 3. Department of Electronics, school of information science and Technology, East China Normal Univer- sity, Shanghai 200062, China 4. Shanghai Cardiovascular Institute, Zhongshan Hospital, Shanghai 200032, China 1. Department of Physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. Department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. Shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2 million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

A multicast routing algorithm with multiple trees

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Journal of Systems Engineering and Electronics 2005年第2期16卷 426-432页

作者： Cui Xunxue 1,2 , Gao Wei3 & Fang Hongyu4.. New Star Research Institute of Applied Technology, Hefei 230031, P. R. China 2. Jiangsu Key Laboratory of Computer information Processing Technology,Soochow university, Suzhou 215006, P. R. China 3. Department of Electronic Engineering and information science,university of science and Technology of China, Hefei 230027, P. R. China 4. school of Electronic science and Technology, Anhui university, Hefei 230039, P. R. China New Star Research Institute of Applied Technology Hefei 230031 P. R. China 2. Jiangsu Key Laboratory of Computer information Processing Technology Soochow University Suzhou 215006 P. R. China Department of Electronic Engineering and information science University of Science and Technology of China Hefei 230027 P. R. China school of Electronic science and Technology Anhui University Hefei 230039 P. R. China

Quality of service (QoS) multicast routing has continued to be a very important research topic in the Internet. A method of multicast routing is proposed to simultaneously optimize several parameters based on multiobjective genetic algorithm, after the related work is reviewed. The contribution lies on that the selection process of such routing is treated with multiobjective optimization. Different quality criterions in IP network are taken into account for multicast communications. A set of routing trees is generated to approximate the Pareto front of multicast problem. Multiple trees can be selected from the final set of nondominated solutions, and applied to obtain a good overall link cost and balance traffic distribution according to some simulation results.

关键词： multicast routing quality of service multiobjective optimization genetic algorithms.

Direct gray-scale extraction of topographic features for vein recognition

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science China(information sciences) 2010年第10期53卷 2062-2074页

作者： KANG WenXiong 1, LI HuaSong 2 & DENG FeiQi 1 1 College of Automation science and Engineering, South China university of Technology, guangzhou 51064., China 2 school of {4. Engineering, Wuyi university, Jiangmen 529000, China 1. College of Automation science and Engineering South China University of Technology Guangzhou 510640 China2. School of Information Engineering Wuyi University Jiangmen 529000 China

Binarization processing is a key step in most vein pattern recognition, but may create flaws such as leakage of some feature information. In order to overcome this problem, a new approach is explored in this paper which can extract topographic features directly from gray-scale vein images without binarization processing. First, an extreme graph of directional fields (EGDF) is calculated according to neighborhood information of every pixel, and then the intravenous main ridge of the image can be separated step by step from EGDF with the defined constraint template sets. After that, the sub-ridge is extracted from end points of the main ridge in range constraint image with the tracing method of maximal neighboring point. According to contrast experiment the proposed method is better than the traditional processing (performing binarization first and then skeletonization), in that it can overcome the problem that some separate vein lines are extracted incorrectly, and it can avoid extracting two neighboring vein lines as one ridge. As such, the proposed method is an effective way to extract topographic features for vein recognition

关键词： vein recognition feature extraction directional fields

A new geometric approach to blind source separation of bounded sources

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Progress in Natural science:Materials International 2009年第7期19卷 891-896页

作者： Jinlong Zhang a, Guoxu Zhoua, Zuyuan Yang a, Xiaoxin Liao b a school of Electrics & information Engineering, South China university of Technology, guangzhou 51064., China b Department of Control {4. and Engineering, Huazhong university of {4. and Technology, Wuhan 4.0074. China [a]school of Electrics & information Engineering South China University of Technology Guangzhou 510641 China [b]Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Based on the minimum-range approach, a new geometric approach is proposed to deal with blind source separation in this paper. The new approach is the batch mode of the original minimum-range approach. Compared with the original approach, the optimization algorithm of the proposed approach needs no parameters and is more efficient and reliable. In addition, the extension of minimum-rangebased approaches is discussed. The simulations show the efficiency of the proposed approach.

关键词： Blind source separation Independent component analysis Minimum-range approach

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 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.