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Landscape Change and its effect on the environment of Daqing City

Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, Harbin Normal university, Harbin 150080, china college of Resources Environment & Tourism, Capital Normal university, beijing 100037, china college of Economics and Management, Northeast agricultural university, Harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China college of Resources Environment and Tourism Capital Normal University Beijing 100037 China college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

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NEW ROBUST UNSUPERVISED SUPPORT VECTOR MACHINES

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Journal of Systems science & Complexity 2011年第3期24卷 466-476页

作者： Kun ZHAO Mingyu ZHANG ~ Naiyang DENG Logistics School Beijing Wuzi University Beijing 101149 China. School of Economic and Management Beijing Jiaotong University Beijing 100044 China. college of science China Agricultural University Bcijing 100083 China.

This paper proposes robust version to unsupervised classification algorithm based on modified robust version of primal problem of standard SVMs, which directly relaxes it with label variables to a semi-definite progra... 详细信息

关键词： Robust semi-definite programming support vector machines unsupervised learning

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Quantum threshold group signature

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science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 college of Computer science and technology, beijing university of technology, beijing 100124, china 2 State Key Laboratory of Integrated Services Network, Xidian university, Xi’an 710071, china 3 State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences), beijing 100049, china 4 State Key Laboratory of Networking and Switching technology, beijing university of Posts and Tele-communications, beijing 100876, china college of Computer science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

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Vaccination against Very Virulent Infectious Bursal Disease Virus Using Recombinant T4 Bacteriophage Displaying Viral Protein VP2

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Acta Biochimica et Biophysica Sinica 2005年第10期37卷 657-664页

作者： Yong-Chang CAO Quan-Cheng SHI Jing-Yun MA Qing-Mei XIE Ying-Zuo BI Genetic Engineering Laboratory,animal science college,South china agricultural university,Guangzou 510642,china Genetic Engineering Laboratory Animal Science College South China Agricultural UniversityGuangzhou 510642 China

In order to develop a desirable inexpensive,effective and safe vaccine against the very virulentinfectious bursal disease virus （vvIBDV）,we tried to take advantage of the emerging T4 bacteriophagesurface protein display *** major immunogen protein VP2 from the vvlBDV strain HK46 wasfused to the nonessential T4 phage surface capsid protein,a small outer capsid （SOC） protein,resulting inthe 49 kDa SOC-VP2 fusion protein,which was verified by sodium dodecylsulfate polyacrylamide gelelectrophoresis and Western *** showed that the recombinant VP2 protein wassuccessfully displayed on the surface of the T4 *** recombinant VP2 protein is antigenic and showedreactivities to various monoclonal antibodies （mAbs） against IBDV,whereas the wild-type phage T4 couldnot react to any *** addition,the recombinant VP2 protein is immunogenic and elicited specific antibodiesin immunized specific pathogen free （SPF） *** significantly,immunization of SPF chickenswith the recombinant T4-VP2 phage protected them from infection by the vvIBDV strain *** with the vvIBDV strain HK46 at a dose of 100 of 50% lethal dose (LD50) per chicken 4 weeksafter the booster was given,the group vaccinated with the T4-VP2 recombinant phage showed no clinicalsigns of disease or death,whereas the unvaccinated group and the group vaccinated with the wild-type T4phage exhibited 100% clinical signs of disease and bursal damages,and 30%—40% ***,the data herein showed that the T4-displayed VP2 protein might be an inexpensive,effective and safe vaccinecandidate against vvIBDV.

关键词： infectious bursal disease virus VP2 T4 bacteriophage vaccination

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Threshold proxy quantum signature scheme with threshold shared verification

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science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 college of Computer science and technology,beijing university of technology,beijing 100124,china 2 State Key Laboratory of Networking and Switching technology,beijing university of Posts and Tele-communications,beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4 State Key Laboratory of Information Security(Graduate university of Chinese Academy of sciences) ,beijing 100049,china college of Computer science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences) Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

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Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

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science china Earth sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of china, beijing Normal university college of Resources science & technology, beijing Normal university, beijing 100875, china Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China college of Resources science & technology Beijing Normal University Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern china in the next 20 years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern china suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern china in the next 20 years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

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Convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations

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science china Mathematics 2006年第2期49卷 255-266页

作者： XIAO Ling, LI Fucai & WANG Shu Academy of Mathematics and Systems science, Chinese Academy of sciences, beijing 100080, china Department of Mathematics, Nanjing university, Nanjing 210093, china college of Applied sciences, beijing university of technology, beijing 100022, china Academy of Mathematics and Systems science Chinese Academy of Sciences Beijing China Department of Mathematics Nanjing University Nanjing China college of Applied sciences Beijing University of Technology Beijing China

We establish the convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations in this paper. The convergence is rigorously proved on the time interval where the smooth solution to the incompressible Euler equations exists. The proof relies on the compactness argument and the so-called relative-entropy method.

关键词： Vlasov-Poisson-Fokker-Planck system incompressible Euler equations relative-entropy method.

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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science china(Technological sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 Center for Agriculture Water Research, china agricultural university, beijing 100083, china 2 Chinese-Israeli International Center for Research and Training in Agriculture, china agricultural university, beijing 100083, china 3 Water Conservancy and Civil Engineering college, Inner Mongolia agricultural university, Hohhot 010018, china Center for Agriculture Water Research China Agricultural University Beijing China Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing China Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Threshold quantum secret sharing between multi-party and multi-party

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science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 college of Computer science and technology,beijing university of technology,beijing 100124,china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences),beijing 100049,china 4 State Key Laboratory of Networking and Switching technology,beijing university of Posts and Tele-communications,beijing 100876,china college of Computer science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences) Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

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Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

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Progress in Natural science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State Key Laboratory for Agrobiotechnology, college of Biological sciences, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu62 was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A24, were isolated. The sequence analysis of loci tagged showed that the Tn5-1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5 transposon.

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