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Impacts of Typhoons Tianying and Dawei on seagrass distribution in Xincun Bay,Hainan Province,china

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Acta Oceanologica Sinica 2011年第1期30卷 32-39页

作者： YANG Dingtian HUANG Daojian CAS key Laboratory of Tropical Marine Environmental Dynamics South China Sea Instituteof Oceanology Chinese Academy of Sciences Guangzhou 510301 China South china institute of Environmental {2. Ministry of Environmental Protection of thePeople＇s Republic of China Guangzhou 510655 China

More than 50% of the typhoons landing in china have landed on the southeast coast, where they have caused great pressure on the coastal environment. Seagrass, one of the most important con- stituents of coastal ecosystems, is also greatly affected by typhoons. In order to clarify how seagrass distribution variation is affected by typhoons in coastal areas in southeast china, data of Typhoons Dawei and Tianying （category 4 and category 2.respectively, which just ran through the southern part of Hainan province） have been studied. In situ observation and satellite remote sensing data （CBERS-{2. Brazil Earth Resources Satellite） in 2.04 and 2.06 were used to retrieve seagrass distribution in Xincun Bay, Hainan province. In situ observations showed that leaf length, stem biomass and above ground biomass on average showed evidence of reduction after Typhoons Tiany- ing and Dawei. However, seagrass density showed no evidence of reduction after typhoon Tianying and Dawei passed by and increased rapidly in January 2.06. From results of satellite remote sensing data, seagrass distribution can be detected with high accuracy, and the area of seagrass distribution on the south coast of Xincun Bay in 2.06 after the typhoon passed by was smaller than that in 2.04 in region A and B. However, in region C, area of seagrass coverage under 2.% increased. These results demonstrated that typhoons Tianying and Dawei damaged seagrass bed and helped seagrass to get rid of aged and dead leaves, and this correspondingly facilitated seagrass growth.

关键词： seagrass Typhoon Tianying and Dawei Xincun Bay

On designated-weight Boolean functions with highest algebraic immunity

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Science china Mathematics 2010年第11期53卷 2847-2854页

作者： LIU MeiCheng1,3, DU YuSong2. PEI DingYi2.& LIN DongDai1 1The State Key Laboratory of Information Security, institute of Software of chinese academy of sciences, Beijing 100190,{2. 2.ollege of Mathematics and Information sciences, guangzhou University, guangzhou 510006,{2. 3Graduate University of chinese academy of sciences, Beijing 100049,{2. 1. The State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. College of Mathematics and Information Sciences Guangzhou University Guangzhou 510006 China

Algebraic immunity has been considered as one of cryptographically significant properties for Boolean functions. In this paper, we study ∑d-1 i=0 (ni)-weight Boolean functions with algebraic immunity achiev-ing the minimum of d and n - d + 1, which is highest for the functions. We present a simpler sufficient and necessary condition for these functions to achieve highest algebraic immunity. In addition, we prove that their algebraic degrees are not less than the maximum of d and n - d + 1, and for d = n1 +2.their nonlinearities equalthe minimum of ∑d-1 i=0 (ni) and ∑ d-1 i=0 (ni). Lastly, we identify two classes of such functions, one having algebraic degree of n or n-1.

关键词： cryptography Boolean function algebraic immunity algebraic degree nonlinearity

Fouling in offshore areas southeast of the Zhujiang(Pearl)River Delta,the northern South china Sea

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Acta Oceanologica Sinica 2003年第2期22卷 201-212页

作者： Yan Tao, Yan Wenxia, Dong Yu, Liang Guanhe, Yan Yan, Wang Huajie South china Sea institute of Oceanology,{2. academy of sciences,guangzhou 510301,china. chinese Acad Sci S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

In order to understand the type and extent of marine fouling in offshore areas southeast ofthe Zhujiang (Pearl) River delta, within the period form May 1986 to June 1987, two biological buoys were deployed at water depths of 95 m and 113 m located in 114 km and 160 km off the coast of Hong Kong, respectively. Moreover, the fouling community of a Marex hydrological buoy located in 115 m depth water 172.km off Hong Kong was also surveyed. The results show that a total of 78 species were collected and identified. The panels exposed for 3 months were mainly dominated by stalked barnacles Conchoderma hunteri and Lepas anatifera and hydroids Orthopyxis sp. As for the buoys, including the subsurface buoy, and their mooring systems exposed for 6 and 12.months, respectively, some hard foulers such as common oysters, pearl oysters, acorn barnacles and bryozoans were also found. The compositions of fouling communities also varied greatly with depth.

关键词： Biofouling offshore structures the South china Sea

Model Test and Design of the Wave Energy System on "Central Fairway No. 1" Light Ship

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china Ocean Engineering 1992年第3期7卷 351-360页

作者： Gao Xiangfan , Liang Xianguang Jiang Niandong Feng Manzhi Wang Wei Senior Engineer, guangzhou institute of Energy Conversion,{2., 510070 guangzhouAssociate Professor, guangzhou institute of Energy Conversion,{2., 510070 guangzhou Engineer, guangzhou institute of Energy Conversion,{2., 510070 guangzhou

This paper presents the test of a ship model for the design of a backward-bent duct oscillating water column type wave energy conversion system, to supply electric power for a light ship. This system suggests a new wa... 详细信息

关键词： model test wave energy oscillating water column (OWC) light ship wave-activated generator

Analytical method of radiation by a wave energy device with dual rectangular floating bodies

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Acta Oceanologica Sinica 2010年第3期29卷 106-115页

作者： WANG Wensheng YOU Yage ZHANG Yunqiu WU Bijun YE Yin guangzhou institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy and Gas Hydrate Chinese Academy Sciences Guangzhou 510640 China Graduate University Chinese Academy of Sciences Beijing 100049 China

The system with one floating rectangular body on the free surface and one submerged rectangular body has been applied to a wave energy conversion device in water of finite depth. The radiation problem by this device on a plane incident wave is solved by the use of an eigenfunction expansion method, and a new analytical expression for the radiation velocity potential is obtained. The wave excitation force is calculated via the known incident wave potential and the radiation potential with a theorem of Haskind employed. To verify the correctness of this method, an example is computed respectively through the bound element method and analytical method. Results show that two numerical methods. are in good agreement, which shows that the present method is applicable. In addition, the trends of hydrodynamic coefficients and wave force are analyzed under different conditions by use of the present analytical method.

关键词： wave energy device hydrodynamic coefficients wave force analytical method

Some properties on multivariate filter banks with a matrix factorization

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Progress in Natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1, XIAO Hongying2. and CHEN Qiuhui3(1. Department of Mathematics, Beijing Jiaotong University, Beijing 100044, china 2. institute of Mathematics, {2. of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, china 3. Department of Scientific Computing and Computer Applications, Zhongshan University, guangzhou 5102.5, china) Department of Mathematics Beijing Jiaotong University Beijing 100044 China. institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China. Department of Scientific Computing and Computer Applications Zhongshan University Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

An ID-based authenticated dynamic group key agreement with optimal round

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Science china(Information sciences) 2012年第11期55卷 2542-2554页

作者： TENG JiKai1,2.WU ChuanKun1 & TANG ChunMing3 1State Key Laboratory of Information Security,institute of Software of chinese academy of sciences,Beijing 100090,{2. 2.raduate University of chinese academy of sciences,Beijing 100049,{2. 3Faculty of Mathematic and Information Science,guangzhou University,guangzhou 510006,{2. 1. State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing 100090 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. Faculty of Mathematic and Information Science Guangzhou University Guangzhou 510006 China

Group key agreement protocols are crucial for achieving secure group *** are designed to provide a set of users with a shared secret key to achieve cryptographic goal over a public *** group membership changes,the session key should be refreshed efficiently and *** previous group key agreement protocols need at least two rounds to establish or refresh session *** this paper,a dynamic authenticated group key agreement(DAGKA) protocol based on identity-based cryptography is *** making use of the members' values stored in previous sessions,our Join and Leave algorithms reduce the computation and communication costs of *** the proposed protocol,Setup and Join algorithms need one *** session key can be refreshed without message exchange among remaining users in Leave algorithm,which makes the protocol more *** security is proved under decisional bilinear Diffie-Hellman(DBDH) assumption in random oracle model.

关键词： identity-based cryptography dynamic group key agreement provably secure admissible pairing

Fractal Features and Computer Simulation of Fan-Shaped Sedimentary Bodies in Faulted Basins

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Journal of Earth Science 1998年第3期17卷 50-51页

作者： Zhou Jiangyu guangzhou institute of {2., chinese academy of sciences, guangzhou 51064. Wu Chonglong Faculty of Earth Resources, china University of Geosciences, Wuhan 430074

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Ｆａｎ－ｓｈａｐｅｄｓｅｄｉｍｅｎｔａｒｙｂｏｄｉｅｓａｒｅｔｈｏｓｅｍａｉｎｌｙｃｏｍ－ｐｏｓｅｄｏｆｔｅｒｉｇｅｎｏｕｓｃｏａｒｓｅｄｅｐｏｓｉｔｓａｎｄｂｅｉｎｇｆａｎ－ｓｈａｐｅｄｉｎｍｏｒｐｈｏｌｏｇｙ，ｉｎｃｌｕｄｉｎｇａｌｕｖｉａｌｆａ...

关键词： fan shaped sedimentary body nonlinear dynamics fractal fractal dimension kriging numerical simulation fault basin.

A METHOD OF PREPARING SPHERICAL NANO-CRYSTAL CELLULOSE WITH MIXED CRYSTALLINE FORMS OF CELLULOSE Ⅰ AND Ⅱ

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chinese Journal of Polymer Science 2001年第3期19卷 291-296页

作者： Xiao-fang Li En-yong Ding Guo-kang Li Laboratory of Cellulose and Lignocellulosics Chemistry, guangzhou institute of Chemistry,{2., guangzhou 510650 china College of Material Science and Engineering South china University of Technology, guangzhou 51064., china 中科院广州化学所广东广州

A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our products are preparedfrom natural cotton fibers. The products are of spherical shape with mixed crystal forms of cellulose I and II. The preparationconditions determine the properties of the products. Prior treatment is a critical procedure. The properties of the products arealso strongly affected by such conditions as the kinds of acids used, the ratio of the acid mixture, the acid concentration, theultrasonic agitation time and hydrolysis temperature. The number average molecular weight of NCC is determined by gelpermeation chromatography (GPC). The particle size and shape were determined by transmission electron microscopy(TEM). X-ray diffraction was used to detect the crystallinity and average crystallite size of the panicle.

关键词： Spherical nano-crystal cellulose Mixed crystal forms of cellulose Ⅰ and Ⅱ, Ultrasonic agitation