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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4 1. The Faculty of Geography and Resources science, Sichuan normal {2., Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, Sichuan, china 3. Graduate {2. of the Chinese Academy of sciences, Beijing 100049, china 4. information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of Geography Resources science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of sciences 100049 Beijing China information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Sequence-based localization algorithm with improved correlation metric and dynamic centroid

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science china({2. sciences) 2011年第11期54卷 2349-2358页

作者： YU Ying 1,JIANG ChunXiao 2.ZHAO XiaoJie 2.YUN LiJun 1,LI ZhiHua 2.& REN Yong 2. College of information,Yunnan normal {2.,Kunming 650500,china 2.Department of Electronic Engineering,Tsinghua {2.,Beijing 100084,china 1. College of information Yunnan Normal University Kunming 650500 China2. Department of Electronic Engineering Tsinghua University Beijing 100084 China

Ecolocation (error controlling localization technique) is a novel sequence-based RF localization algorithm.A key feature of the Ecolocation algorithm is that it constructs a constraint table based on RSSI values and compares data between two ***,the definitions of the constraint and the centroid in the Ecolocation algorithm are imperfect,and result in poor localization *** improve the localization accuracy,a new algorithm based on weighted rank order correlation coefficient and dynamic centroid method is *** results indicate that compared with the Ecolocation,the localization accuracy and robustness of the new algorithm are distinctly raised.

关键词： WSNs (wireless sensor networks) localization sequences constraint table rank order correlation coefficient

Process and mechanism of arable land change in hebei Province during the past 50 years

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Journal of Geographical sciences 2001年第4期11卷 47-52页

作者： XU Yue-qing (Institute of Geographical sciences and Natural Resources Research, CAS, Beijing 100101, china College of Resource and Environment science, hebei normal university, shijiazhuang 050016, china ) CAS Institute of Geographical Sciences and Natural Resources Research Beijing China (GRID:grid.9227.e) (ISNI:***) hebei normal {2. College of Resource and Environment Science Shijiazhuang China (GRID:grid.256884.5) (ISNI:***)

hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in china. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable *** paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.2. km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc.

关键词： decrease in arable land area changing process mechanism hebei Province

Exchange bias for ferromagnetic/antiferromagnetic bilayers with the uniaxial anisotropy being misaligned with the exchange anisotropy

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science china(Physics,Mechanics & Astronomy) 2009年第12期52卷 1885-1892页

作者： BAI YuHao1 & YUN GuoHong1,2.1 College of Physical science and Technology,Inner Mongolia university,Hohhot 01002.,{2. 2.Key Laboratory of Physics and Chemistry of Functional Materials,College of Physics and Electronic information,Inner Mongolia normal university,Hohhot 01002.,{2. 1. College of Physical science and Technology Inner Mongolia University Hohhot 010021 China 2. Key Laboratory of Physics and Chemistry of Functional Materials College of Physics and Electronic Information Inner Mongolia Normal University Hohhot 010022 China

Using the principle of minimal energy and S-W model,the exchange bias for ferromagnetic/antiferro-magnetic bilayers has been investigated when the uniaxial anisotropy is misaligned with the exchange anisotropy. According to the relation between the energy of the bilayer and the orientation of ferro-magnetic magnetization,it is found that the bilayer will be in the monostable state or bistable state when the external field is absent in the initial magnetization state. The monostable state or bistable state of the bilayer,which determines the angular dependence of exchange bias directly,is controlled by the competition between the exchange anisotropy and uniaxial anisotropy. When the applied field is parallel to the intrinsic easy axes and intrinsic hard axes,one of the switching fields of the hysteresis loop shows an abrupt change,while the other keep continuous by analyzing the magnetization reversal processes. Consequently,the exchange bias field and the coercivity will show a jump phenomenon. The numerical calculations indicate that both the magnitude and direction of the exchange anisotropy will significantly affect the angular dependence of exchange bias. The jump phenomenon of exchange bias is an intrinsic property of the bilayer,which is dependent on the interfacial exchange-coupling constant,the orientation of the exchange anisotropy,the thickness and uniaxial anisotropy constant of the ferromagnetic layer.

关键词： monostable state bistable state intrinstic easy axis intrinstic hard axis switching field

A NEWε-GENERALIZED PROJECTION METHOD OF STRONGLY SUB-FEASIBLE DIRECTIONS FOR INEQUALITY CONSTRAINED OPTIMIZATION

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Journal of Systems science & Complexity 2011年第3期24卷 604-618页

作者： Jinbao JIAN Guodong MA Chuanhao GUO College of mathematics and information {2. Guangxi University Nanning 530004 China Department of mathematics and Computer science Yulin Normal University Yulin 537000 China College of science Shanghai University Shanghai 200444 China.

In this paper, the nonlinear optimization problems with inequality constraints are discussed. Combining the ideas of the strongly sub-feasible directions method and the s-generalized projection technique, a new algorithm starting with an arbitrary initial iteration point for the discussed problems is presented. At each iteration, the search direction is generated by a new s-generalized projection explicit formula, and the step length is yielded by a new Armijo line search. Under some necessary assumptions, not only the algorithm possesses global and strong convergence, but also the iterative points always get into the feasible set after finite iterations. Finally, some preliminary numerical results are reported.

关键词： E-generalized projection global and strong convergence inequality constraints method of strongly sub-feasible directions optimization.

Entropy product measure for multipartite pure states

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science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2. LIU Dan2. PAN Feng3 & LONG Guilu2.4 1. Department of Physics, Chifeng College, Chifeng 02.001, china 2. Key Laboratory for Quantum information and Measurements, Department of Physics, Tsinghua {2., Beijing 100084, china 3. Department of Physics, Liaoning normal {2., Dalian 11602., china 4. Key Laboratory for Atomic and Molecular Nano-sciences, Tsinghua {2., Beijing 100084, china Correspondence should be addressed to Long Guilu Department of Physics Chifeng College Chifeng 024001 China Key Laboratory for Quantum information Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Physics Liaoning Normal University Dalian 116029 China Key Laboratory for Atomic Molecular Nano-sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Seamlet carving for shape-aware image resizing

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science china({2. sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2.SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3 1 Department of Computer science and Engineering,Shanghai Jiao Tong university,Shanghai 2.02.0,{2. 2.Academy of information Technology,Luoyang normal university,Luoyang 47102.,{2. 3 Department of Computer science and Engineering,East china university of science and Technology,Shanghai 2.02.7,{2. 1. Department of Computer science and Engineering Shanghai Jiao Tong University Shanghai 200240 China2. Academy of Information Technology Luoyang Normal University Luoyang 471022 China3. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2. The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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science china({2. sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3 , YAO Li 1,2., XIONG Shi 2.& ZHANG JiaCai 2.1 National Key Laboratory of Cognitive Neuroscience and Learning, Beijing normal {2., Beijing 100875, china 2.College of information science and Technology, Beijing normal {2., Beijing 100875, china 3 Biomedical Imaging Technology Center, Emory {2./Georgia Institute of Technology, Atlanta 3032., USA 1. National Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China3. Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta 30322 USA2. College of Information Science and Technology Beijing Normal University Beijing 100875 China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

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science china Earth sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2. DENG Chenglong1, ZHU Rixiang1 & XIE Fei3 1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sci- ences, Beijing 10002., china 2. School of the Earth sciences and Resources, china university of Geosciences, Beijing 100083, china 3. hebei Province Institute of Cultural Relics, shijiazhuang 050000, china 1. Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. School of the Earth sciences and Resources China University of Geosciences Beijing 100083 China 3. hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3 and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.