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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 5. Years

Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , chengdu 610041,{2., china 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3.{2. Institute of Land Resource Management, chengdu 610041,{2. , china 4. Department of Resources and Environment Science,{2. Normal University , chengdu 610061,{2., china 5. college of information engineering, chengdu University of technology,{15.,{2., china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China college of information {2. Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995.the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 5. years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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The Research of the Teaching Reform of the information Professional English in Higher Agricultural college

The Research of the Teaching Reform of the Information Profe...

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第二届亚太地区信息论学术会议

作者： Yu TANG 1 2.Chuanju LIU 1 Keqiang WANG 1 Jimei HUANG 1 1 college of information Zhongkai University of Agriculture and {2. Guangzhou china 2.School of Electronic and information {2. South china University of technology Guangzhou china

According to the features of information professional English in higher agricultural college and combined with many years of teaching experience in information professional English,we study on the teaching reform of information professional *** on the current problems in the teaching process,we study on the necessity of the teaching reform and the specific measures in the information professional *** paper mainly study on the teaching reform of the information profession English in higher agricultural college form the construction of teaching staff,the innovation of teaching mode and the building of the teaching materials.

关键词： Profession English Teaching Mode Teaching Reform

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Image space analysis for variational inequalities with cone constraints and applications to traffic equilibria

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Science china Mathematics 2012年第4期55卷 851-868页

作者： LI Jun 1,& HUANG NanJing 2.1 college of Mathematics and information,{2. West Normal University,Nanchong 637009,{2. 2.Department of Mathematics,sichuan University,{5. 610064,{2. 1. college of Mathematics and information China West Normal University Nanchong 637009 China2. Department of Mathematics Sichuan University Chengdu 610064 China

In this paper,the image space analysis (for short,ISA) is employed to investigate variational in- equalities (for short,VI) with cone *** separation for VI with cone constraints is characterized by using the normal cone to a regularization of the image,and saddle points of the generalized Lagrangian func- ***-type necessary and sufficient optimality conditions for VI with cone constraints are presented by using a separation *** functions and weak sharpness for VI with cone constraints are also investi- ***,the obtained results are applied to standard and time-dependent traffic equilibria introduced by Daniele,Maugeri and Oettli.

关键词： variational inequality image space analysis linear separation necessary and sufficient optimalitycondition traffic equilibrium

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Efficient Array Coding Scheme for Large-Scale Storage Systems

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Journal of Electronic Science and technology 2015年第2期13卷 102-106页

作者： Dan Tang Software engineering college Chengdu University of Information Technology

A family of array codes with a maximum distance separable（MDS） property, named L codes, is proposed. The greatest strength of L codes is that the number of rows（columns） in a disk array does not be restricted by the prime number, and more disks can be dynamically appended in a running storage system. L codes can tolerate at least two disk erasures and some sector loss simultaneously, and can tolerate multiple disk erasures（greater than or equal to three） under a certain condition. Because only XOR operations are needed in the process of encoding and decoding, L codes have very high computing efficiency which is roughly equivalent to X codes. Analysis shows that L codes are particularly suitable for large-scale storage systems.

关键词： codes decoding dynamically parity restricted sector encoding operations running correcting

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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, sichuan University,chengdu 610065.{5. [a] State Key Laboratory of Polymer Materials engineering College of Polymer Science 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

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5. LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 3. college of Resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of Science and technology, P. C. china, Beijing 100862. china 5. chengdu Institute of Biology, Chinese Academy of Sciences, chengdu 610041, china 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. college of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and technology P. C. China 100862 Beijing China 5. chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Frequency/time hopping sequence sets with optimal partial Hamming correlation properties

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Science china(information Sciences) 2012年第10期55卷 2207-2215页

作者： NIU XianHua 1,2.PENG DaiYuan 1 & ZHOU ZhengChun 3 1 The Provincial Key Laboratory of information Coding and Transmission,Institute of Mobile Communications,Southwest Jiaotong University,chengdu 610031,{2. 2.The School of Mathematics and Computer engineering,Xihua University,chengdu 610039,{2. 3 The college of Maths,Southwest Jiaotong University,chengdu 610031,{2. 1. The Provincial Key Laboratory of information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu 610031 China 2. The School of Mathematics and Computer engineering Xihua University Chengdu 610039 China 3. The college of Maths Southwest Jiaotong University Chengdu 610031 China

Frequency hopping/time hopping(FH/TH) sequences have found wide applications in various modern FH/TH spread spectrum communications,such as digital cellular mobile communication,short-range wireless communication,personal communication,and multi-user radar,sonar *** order to evaluate the goodness of FH/TH sequences design,the periodic Hamming correlation function is used as an important ***,the length of correlation window is shorter than the period of the chosen FH/TH sequence,so the study of the partial Hamming correlation of FH/TH sequence is particularly *** this paper,a new class of FH/TH sequence sets with good partial Hamming correlation properties is proposed and *** construction of new FH/TH sequence sets is based upon the generalized m-sequence and generalized Gordon-Mills-Welch sequence over a polynomial residue class *** is shown that new FH/TH sequence sets are optimal with respect to the partial Hamming correlation bound.

关键词： frequency hopping/time hopping(FH/TH) sequence partial Hamming correlation optimal FH/TH sequence set

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同时计算实序列的DFT和实序列的DFT的IDFT的新公式

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上海交通大学学报 2008年第12期42卷 2052-2055页

作者：范安东成都理工大学信息管理学院成都610059

通过对离散傅里叶变换(DFT)的一些性质的分析,利用DFT的对称性和将一个复序列分解为4个奇偶序列之和的方法,改正了Gunther关于直接计算双实序列的DFT和实序列的DFT和逆离散傅里叶变换(IDFT)的公式中的少数错误,给出了新的同时计算实序列... 详细信息

通过对离散傅里叶变换(DFT)的一些性质的分析,利用DFT的对称性和将一个复序列分解为4个奇偶序列之和的方法,改正了Gunther关于直接计算双实序列的DFT和实序列的DFT和逆离散傅里叶变换(IDFT)的公式中的少数错误,给出了新的同时计算实序列的DFT和实序列的DFT的IDFT的直接公式,并给出了证明.

关键词：对称性离散傅里叶变换逆离散傅里叶变换

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Single-channel blind separation of overlapped multicomponents based on energy operator

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Science china(information Sciences) 2010年第1期53卷 147-157页

作者： CAI QuanWei, WEI Ping & XIAO XianCi college of Electronic engineering, University of Electronic Science and {2. of china, chengdu 61005., china 1. college of Electronic engineering University of Electronic Science and Technology of China Chengdu 610054 China

A method utilizing single channel recordings to blind separate the multicomponents overlapped in both time and frequency domains is proposed in this paper. The main idea of the method is based on using the energy operator and differential energy operator to estimate instantaneous frequencies and amplitudes of each component and then to reconstruct these components. This method, due to the good time resolution of the energy operator and differential energy operator, as well as the very low computational complexity, is very useful in real time processing and practical applications. Simulation results demonstrated the effciency of this method.

关键词： single channel time frequency overlap multicomponents separation energy operator differential energy operator

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Synthesis and Luminescence Properties of Red Phosphor CaO:Eu^(3+)

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Journal of Wuhan University of technology(Materials Science) 2009年第1期24卷 20-24页

作者：康明 School of Material Science and engineering Southwest University of Science and Technology college of Materials Science and engineering Sichuan University

Ca（NO3）2.4H2., Eu（NO3）3 and H2.2.4·2.2. were adopted to synthesize CaO： Eu3＋ with the chemical co-precipitation method, and the effects of the calcination temperature and Eu3＋ doping concentration on the phosphor structure and its luminescent properties were investigated by TG-SDTA, XRD, and PL-PLE. The results confirm that the Eu3＋ ions as luminescent centers substi-tutes Ca2. sites without changing the crystal structure of cubic CaO. The optimum calcination tem-perature and the optimum concentration of Eu3＋ are 1 100 ℃ and 1 mol%, respectively, under which the best crystallinity and highest PL intensity appeared. The maximum emission wavelength is 5.2.nm （5.0→7F1） which is excited by xenon lamp with the wavelength of 2.0-2.0 nm, indicating that the Eu3＋ ion mainly locates in the symmetric position （Oh） in the crystal lattice of CaO.

关键词： red phosphor CaO Eu^3+ co-precipitation method rare earths

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