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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 university, {3. 610066, sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, {3. 610041, sichuan, china 3. Graduate university of the Chinese Academy of sciences, Beijing 100049, china 4. Information Center of Land and Resources {13. of sichuan Province, {3. 610041, sichuan, china The Faculty of Geography and Resources science Sichuan Normal University Chengdu Sichuan China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of the Chinese Academy of sciences Beijing China Information Center of Land and Resources department of sichuan Province 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 2002. 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 3.°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. 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

CMC surfaces in the hyperbolic 3.space

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Chinese science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2 and LI Zhenqi 1, 3.1. Institute of Mathematics, Fudan university, Shanghai 20043., china 2. department of Mathematics,{3. Union university, chengdu 610064, china 3. department of Mathematics, Nanchang university, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Synthesis of a novel benzoxazine containing benzoxazole structure

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Chinese Chemical Letters 2010年第5期21卷 558-562页

作者： Po Yang,Yi Gu State Key Laboratory of Polymer Materials engineering,College of Polymer science and engineering,{3.,chengdu 610065,china State Key Laboratory of Polymer Materials engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065 China

A high-purity benzoxazine（Boz-BOA） containing benzoxazole structure was successfully synthesized by three-step synthetic method using 2-（4-aminophenyl）-1H-benzoxazole-5-amine（BOA） and *** structure of Boz-BOA was confirmed by FTIR and;H NMR *** DSC was utilized to probe the curing behavior of Boz-BOA and exhibited a narrow melting peak and curing exothermic peak.

关键词： Benzoxazine Benzoxazole Synthesis Characterization

A new grid-associated algorithm in the distributed hydrological model simulations

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science china(Technological sciences) 2010年第1期53卷 235-241页

作者： XU Rui1,2,HUANG XiaoXue1,LUO Lin1 & LI ShaoCai3.1 State Key Laboratory of Hydraulics and Mountain River engineering College of Architecture and Environment,sichuan university,{3. 610065,china 2 College of Electronic engineering,Guilin university of Electronic Technology,Guilin 541004,china 3.College of Life sciences,sichuan university,{3. 610065,china State Key Laboratory of Hydraulics and Mountain River engineering College of Architecture and Environment Sichuan University College of Electronic engineering Guilin University of Electronic Technology

This paper presents a new grid-associated algorithm to improve the performance of a D8 algorithm based distributed hydrological model *** algorithm is based on the well known single-flow D8 algorithm of grid *** algorithm allocates calculation priorities according to the distance between the units and the outlet,then carries out the ergodic computations of the hydrological units according to the priority *** the parallelized algorithm,a standard thread-level shared memory system for parallel programming(OpenMP-Open specifications for Multi Processing) was introduced,and the parallel coding was implemented in C lan-guage.A case study showed that the absolute speed-up ratio of the grid-associated algorithm is 1.64 over the original D8 algorithm,and the linear speed-up ratio of the parallel associated algorithm is 2.42 under 4 *** parallel grid-associated algorithm can be applied to a variety of research fields that use the grid method.

关键词： distributed hydrological model grid-association algorithm OpenMP parallel computing

A self-adaptive negative selection algorithm used for anomaly detection

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Progress in Natural science:Materials International 2009年第2期19卷 261-266页

作者： Jinquan Zeng,Xiaojie Liu,Tao Li,Caiming Liu,Lingxi Peng,Feixian Sun department of Computer science,sichuan {3.,chengdu 610065,china department of Computer science Sichuan University Chengdu 610065 China

A novel negative selection algorithm (NSA),which is referred to as ANSA,is presented. In many actual anomaly detection systems,the training data are just partially composed of the normal elements,and the self/nonself space often varies over time. Therefore,anom-aly detection system has to build the profile of the system based on a part of self elements and adjust itself to adapt those variables. However,previous NSAs need a large number of self elements to build the profile of the system,and lack adaptability. In order to over-come these limitations,the proposed approach uses a novel technique to adjust the self radius and evolve the nonself-covering detectors to build an appropriate profile of the system. To determine the performance of the approach,the experiments with the well-known data-set were performed. Results exhibited that our proposed approach outperforms the previous techniques.

关键词： Artificial immune system Anomaly detection Negative selection algorithm

A novel evolving model for power grids

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science china(Technological sciences) 2010年第10期53卷 2862-2866页

作者： LIU Xuan, LIU TianQi & LI XingYuan School of Electrical engineering and Automation, sichuan university, chengdu {3., china School of Electrical engineering and Automation Sichuan University

In this paper,a novel power grid evolving model,which can well describe the evolving property of power grids,is presented. Based on the BA model,motivated by the fact that in real power grids,connectivity of node not only depends on its degree,but also is influenced by many uncertain factors,so we introduce the subconnection factor K for each node. Using the mean-field theory,we get the analytical expression of power-law degree distribution with the exponent γ∈ (3.∞ ). Finally,simulation results show that the new model can provide a satisfactory description for empirical characteristics of power network,and power network falls somewhere in between scale-free network and uncertain network.

关键词： power grid evolving model scale-free

EFFECT OF PROCESSING METHOD ON THE IMPACT STRENGTH OF POM/TPU/CaCO_3.TERNARY COMPOSITES

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Chinese Journal of Polymer science 2005年第5期23卷 531-537页

作者： Xiao-ling Gao Cheng Qu Qin Zhang Rong-ni Du and Qiang Fu department of Polymer science & Materials,sichuan {3.,State Key Laboratory of Polymer Materials engineering,chengdu 610065,china department of Polymer science & Materials Sichuan University State Key Laboratory of Polymer Materials Engineering Chengdu 610065

Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3. were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3.content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3.particles.

关键词： POM/TPU/CaCO3.composites Core-shell structure Impact strength.

Preparation of Pt/K_2La_2Ti_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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science china Chemistry 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3. LIU Li2, FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. chengdu Institute of Organic Chemistry, Chinese Academy of sciences, chengdu 610041,{3. 2. Chemistry department, sichuan university of science & engineering, Zigong 643.3.,{3. 3. Graduate School of the Chinese Academy of sciences, Beijing 10003.,{3. Correspondence should be addressed to Qiu Fali chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu China Graduate School of the Chinese Academy of sciences Beijing China Chemistry department Sichuan University of Science & Engineering Zigong China

A layered perovskite-type oxide K2La2Ti3.10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2La2Ti3.10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3.10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2La2Ti3.10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 23..88 μmol·h?1 by Pt(2%)/K2La2Ti3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3._(10) support

TOEPLITZ OPERATORS AND ALGEBRAS ON DIRICHLET SPACES

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Chinese Annals of Mathematics,Series B 2002年第3期23卷 385-396页

作者： CAO GUANGFU department of Mathematics, sichuan university, chengdu 610064,{3.. department of Mathematics Sichuan University Chengdu 610064 China

The automorphism group of the Toeplitz C^*- algebra, J(C^1), generated by Toeplitz op-erators with C^1-symbols on Dirichlet space D is discussed; the K0, K1-groups and the first cohomology group of J(C^1) are computed. In addition, the author proves that the spectra of Toeplitz operators with C^1-symbols are always connected, and discusses the algebraic prop-erties of Toeplitz *** particular, it is proved that there is no nontrivial selfadjoint Toeplitz operator on D and Tψ^* = Tψ^- if and only if Tψ is a scalar operator.

关键词： Dirichlet space Toeplitz operator Toeplitz algebra