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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, sichuan, china 2. Graduate university of Chinese Academy of Sciences, Beijing 100049, china 3. sichuan Institute of Land Resource Management, chengdu 610041, sichuan , china 4. Department of Resources and Environment Science, sichuan Normal university , chengdu 610061, sichuan, china 5. college of information engineering,{15., chengdu 61005., sichuan, 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 engineering 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 2002; 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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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,{5. 610065.china [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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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 technology of china,{5., 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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Integrated optimization methods in multisensor decision and estimation fusion

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Science china(information Sciences) 2012年第3期55卷 545-550页

作者： LUO YingTing, SHEN XiaoJing & ZHU YunMin college of Mathematics, sichuan university chengdu, 610064, china 1. college of Mathematics Sichuan University Chengdu 610064 China

This paper presents a significant integrated optimization point of view behind the following three successful decision and estimation fusion results: 1) a unified fusion rule for networked sensor decision systems; 2) optimal sensor data quantization for estimation fusion and 3) integrated multi-target data association tracking systems. More precisely speaking, the integrated optimization method in 1) derives a unified objective function optimizing only sensor rules given a unified fusion rule; the method in 2) derives a unified objective function optimizing both the sensor quantization rule and the final estimation in the MSE sense, and the method in 3) integrates all associated targets and their valid observations into a whole random measurement matrix dynamic system so that the optimal random matrix Kalman filtering can be applied to estimate the states of all associated targets.

关键词： integrated optimization decision fusion estimation fusion data association

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TRANSIENT QUEUE SIZE DISTRIBUTION SOLUTION OF GEOM/G/1 QUEUE WITH FEEDBACK-A RECURSIVE METHOD

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Journal of Systems Science & Complexity 2009年第2期22卷 303-312页

作者： Chuanyi LUO Yinghui TANG Cailiang LI Department of Economic Mathematics Southwestern University of Finance and Economics Chengdu 610074China. School of Mathematics and Software Science Sichuan Normal University Chengdu 610066 China. Department of information and Computer Science Chengdu Electron-Mechanical College Chengdu 610031China.

This paper considers the Geom/G/1 queueing model with feedback according to a late arrival system with delayed access （LASDA）. Using recursive method, this paper studies the transient property of the queue size from the initial state N（0＋） = i. Some new results about the recursive expression of the transient queue size distribution at any epoch n＋ and the recursive formulae of the equilibrium distribution are obtained. Furthermore, the recursive formulae of the equilibrium queue size distribution at epoch n-, and n are obtained, too. The important relations between stationary queue size distributions at different epochs are discovered （being different from the relations given in M/G/I queueing system）. The model discussed in this paper can be widely applied in all kinds of communications and computer network.

关键词： Discrete time queue equilibrium distribution feedback recursive expression transient distribution.

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Chromo-chemodosimetric detection for Fe^(2+) by Fenton reagent-induced chromophore-decolorizing of halogenated phenolsulfonphthalein derivatives

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Science china Chemistry 2010年第6期53卷 1398-1405页

作者： ZHENG Kuan,LAI ChengYue,HE LiPing & LI Fang Key Laboratory of Green Chemistry and technology,Ministry of Education college of Chemistry,sichuan university,chengdu 610064,{5. 1. Key Laboratory of Green Chemistry and technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China

A commercially-available sulfonphthalein derivative was demonstrated to be a chemodosimeter for Fe2+ and its sensing behavior was further investigated by UV-vis spectroscopy in aqueous media under the optimum *** the presence of chlorophenol red (CPR) and H2O2,the absorption maximum at 435.nm decreased upon addition of Fe2+,resulting in a significant color change of the CPR solution from yellow to *** chemosensor system did not show significant responses to a series of other metal ions including Al3+,Zn2+,Cd2+,Hg2+,Mn2+,Co2+,Fe3+,Ni2+,Cu2+,La3+,Ce4+,Th4+,Pd2+,Pb2+,Sb3+,Cr3+,Au3+,Ag+,Nd3+,Sm3+,alkali and alkaline earth metal cations,allowing for highly selective naked-eye detection of Fe2+.Quantitative analysis was carried out kinetically for practicable the Fe2+ assay when either fixed time method or the initial rate method was *** the detecting time was set,the decrease of absorbance signal was linear with Fe2+ concentration in the range of 0 to 7.5. × 10-5.mol L-1 and the regression equation was ΔA = 0.0075. + 0.005.3CFe with a correlation coefficient r = *** chemodosimetric system has employed an irreversible Fenton reagent-promoted oxidation of the CPR free chromophore and the hydroxyl radicals were generated in the presence of both Fe2+ and hydrogen *** mechanistic interpretation of the signaling process was partially confirmed by the radical scavenging experiment and the FT-IR analysis of the intermediates formed at different reaction periods.

关键词： colorimetric chemosensor ferrous ion sulfonphthalein Fenton reagent

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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,china West Normal university,Nanchong 637009,china 2 Department of Mathematics,{5. university,chengdu 610064,china 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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Synthesis mechanism of LiNiVO_4 by wet chemical method and mixed valence of nickel and vanadium

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Chinese Science Bulletin 2002年第6期47卷 454-457页

作者： LAI Qiongyu, LU Jizheng, Jl Xiaoyang, YAN Fangyong, WEI Yongqiang & YU DingChemical college, sichuan university, chengdu 610064, china Analytical and Testing Center, sichuan university, chengdu 610064, china Chemical college Sichuan University Chengdu China Analytical and Testing Center Sichuan University Chengdu China

The single phase LiNiVO4 has been successfully synthesized by adopting a new mild liquid route with oxalic acid as both complexant and precipitant, and this method is named the CPG method. The products were obtained by sintering the dry gel precursor which was prepared by the CPG method at 200-85.°C for 2-10 h in air. The products were tested by XRD, XPS, ESR and TGA-DTA, and the results indicate that the single phase LiNiVO4 could be obtained at 45.°C for 2-3 h in air and LiNiVO4 was still steady at 85.°C for 10 h. The valence analyses show that in LiNiVO4 the valence of lithium is +1, both nickel and vanadium have the mixed valence, namely +2, +3 for nickel and +4, +5.for vanadium respectively. The LiNiVO4 can be expressed as LiNi3+xNi2+1-xV4+xV5.1-xO4 (O≤x<1). The pyrolysis mechanism of the dry gel is also discussed.

关键词： LiNiVO4 CPG method dry gel pyrolysis mechanism mixed valence.

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Globally optimal distributed Kalman filtering fusion

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Science china(information Sciences) 2012年第3期55卷 512-529页

作者： SHEN XiaoJing, LUO YingTing , ZHU YunMin & SONG EnBin college of Mathematics, sichuan university, chengdu 610064, china 1. college of Mathematics Sichuan University Chengdu 610064 China

The goal of this paper is to give a survey of the previous works on the globally optimal distributed Kalman filtering fusion with classical and nonclassical dynamic systems. Then, we summarize some of our recent results on nonclassical and unideal dynamic systems, including dynamic systems with feedback and cross-correlated sensor measurement noises, dynamic systems with random parameter matrices, and dynamic systems with out-of-sequence or asynchronous measurements. The global optimality in this paper means that the distributed Kalman filtering fusion is exactly equal to the corresponding centralized optimal Kalman filtering fusion. Therefore, not only all of the proposed fusion algorithms here are distributed, but performance as good as that of the corresponding optimal centralized fusion algorithms is achieved. There also exist many papers for other fusion optimality (e.g., the optimal convex linear estimation/compression fusion) discussion, which are not involved in this paper.

关键词： Kalman filtering distributed estimation fusion feedback cross-correlated sensor measurement noises random Kalman filtering out-of-sequence measurements

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