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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, chengdu University of Technology, chengdu 610059, 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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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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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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Optimizing of Culture Conditionin Horizontal Rotating Bioreactor

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生物医学工程学杂志 2005年第S1期22卷 129-130页

作者： Yan-Fang ZHANG~(1,2) Huai-Qing CHEN~1 Hua HUANG~31(Institute of Biomedical engineering, West china Medical Center, sichuan University, chengdu 610041, china)2(Physics Department of Guangdong Medicinal {5., Zhanjiang 5.4023,china)3 (Medical information engineering Department, sichuan University, chengdu 610041, china) Institute of Biomedical engineering West China Medical Center Sichuan University Chengdu 610041 China Physics Department of Guangdong Medicinal college Zhanjiang 524023 China Institute of Biomedical engineering West China Medical Center Sichuan University Chengdu 610041 China Medical information engineering Department Sichuan University Chengdu 610041 China

1 IntroductionBioreactor is the most important equipment in tissue engineering. It can mimic the micro-environment of cell growth in vitro. At present, horizontal rotating bioreactor is the most advanced equipment for... 详细信息

关键词： Optimizing of Culture Conditionin Horizontal Rotating Bioreactor cell

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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, 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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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,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 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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一维大地电磁测深几种反演算法的比较研究

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石油地球物理勘探 2004年第5期39卷 594-599,498-628页

作者：冯思臣王绪本阮帅成都理工大学油气藏地质及开发工程国家重点实验室教育部地球探测与信息技术重点实验室

大地电磁反演算法主要分为线性与非线性两类。马奎特法、遗传算法以及模拟退火是其中具有代表性的算法。本文将三种方法的反演过程、结果及理论进行了对比研究 ,指出各自的优点与局限性 ,以及使用时应注意的相应条件。研究表明 ,马奎特... 详细信息

大地电磁反演算法主要分为线性与非线性两类。马奎特法、遗传算法以及模拟退火是其中具有代表性的算法。本文将三种方法的反演过程、结果及理论进行了对比研究 ,指出各自的优点与局限性 ,以及使用时应注意的相应条件。研究表明 ,马奎特法寻找目标函数全局最优的能力较差 ,只能局部寻优 ,但运算速度快 ;模拟退火法和遗传算法寻找目标函数全局最优的能力较强 ,但运算速度较慢。当对地下地电参数预先有一定程度了解 ,又可以选取比较合理的初始解时 ,可选择马奎特法 ,否则宜选用其他非线性全局寻优能力强的反演方法。

关键词：大地电磁测深反演算法反演方法模拟退火法目标函数代表性电参数一维初始解全局寻优能力

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基于边缘特征的单帧图像清晰度判定

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计算机工程与应用 2009年第30期45卷 198-199,203页

作者：杨斯涵成都理工大学信息工程学院成都610059

自动调焦是保证目标跟踪系统实时获得清晰图像的重要技术,而何时触发调焦又成为了其中的关键问题。在图像清晰时如果触发调焦,初始的电机盲动会导致图像可能变得更模糊。提出了一种可单帧判断图像是否清晰的方法,消除了图像在清晰情况... 详细信息

自动调焦是保证目标跟踪系统实时获得清晰图像的重要技术,而何时触发调焦又成为了其中的关键问题。在图像清晰时如果触发调焦,初始的电机盲动会导致图像可能变得更模糊。提出了一种可单帧判断图像是否清晰的方法,消除了图像在清晰情况下却触发调焦的误操作,从而提高了跟踪的可靠性和精度。通过对多组实际图像序列的测试,证明该方法合理可靠。

关键词：图像清晰度自动调焦单帧

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一种基于网格剖分的两点射线追踪方法

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西南石油大学学报（自然科学版） 2010年第2期32卷 53-57,198页

作者：梅胜全钟本善成都理工大学信息工程学院四川成都610059

两点射线追踪是解决复杂地质结构下反射波射线正演的有效方法。在初至波层析射线追踪算法基础上,提出了一种两点射线追踪方法,利用层析网格对模型进行离散化,通过两阶段法射线追踪,分别对激发点和接收点按向前处理过程计算模型单元及节... 详细信息

两点射线追踪是解决复杂地质结构下反射波射线正演的有效方法。在初至波层析射线追踪算法基础上,提出了一种两点射线追踪方法,利用层析网格对模型进行离散化,通过两阶段法射线追踪,分别对激发点和接收点按向前处理过程计算模型单元及节点的旅行时,两次时间相加作为最小旅行时,再在目的层界面邻域扫描最小旅行时子震源网格单元,用粒子群算法在该单元内扫描全局最小旅行时点,得到反射点位置与反射夹角,再利用向后处理过程运用旅行时线性插值算法,从反射点分别到激发点、接收点反向追踪射线路径,最后得到反射波两点射线路径。

关键词：旅行时线性插值算法网格剖分两点射线追踪初至波地震勘探方法

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Investigation on the 773 K isothermal section of La-Fe-Sn ternary systems by X-ray powder diffraction

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Rare Metals 2010年第6期29卷 567-571页

作者： CHEN Xiang ZHUANG Yinghong CHEN Yungui Key Laboratory of Nonferrous Metal and New Processing Technology of Materials (Ministry of Education of china) Guangxi University Nanning 530004 China Department of Physics and Electronic information engineering Neijiang Teachers College Neijiang 641002 China Department of Metallic Materials engineering Sichuan University Chengdu 610065 China

The 773 K isothermal section of the La-Fe-Sn ternary system was investigated and constructed by X-ray powder diffraction（XRD）.The existence of two reported ternary intermetallic compounds,La6Fe13Sn and La3FeSn6,is confirmed in this *** with other R-Fe-Sn phase diagrams（R = Pr and Sm）,the binary alloys Fe3Sn and Fe5.n3 are not *** compound Fe3Sn2 was observed from the XRD pattern of Fe3Sn2 samples,but it is not an equilibrium phase at 773 K and decomposes into Fe and FeSn phases completely for a longer heat treated *** to now,the crystal structure data of La2Sn3 has not been reported,so the X-ray pattern of La2Sn3 was only *** phase relationship for this compound was drawn by a dotted line.

关键词： intermetallics quenching phase diagrams X-ray diffraction.

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