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Landscape Change and its effect on the environment of Daqing City

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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 & 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.

Research on the method for retrieving soil moisture using thermal inertia model

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science china Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information college, South china agricultural university, Guangzhou 510642, china 2. Graduate university of Chinese Academy of sciences, Beijing 100049, china 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 college of Resources and Environmental science, Nanjing agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China college of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Cluster based node scheduling method for wireless sensor networks

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science china(Information sciences) 2012年第4期55卷 755-764页

作者： WANG Lei 1,2,WEI RuiZhong 2 & TIAN ZiHong 2,3 1 college of Software,Hunan university,Changsha 410082,china 2 Department of Computer science,Lakehead university,Thunder Bay P7B 5E1,Canada 3 Mathematics and Information science college,hebei Normal university,Shijiazhuang 050016,china 1. college of Software Hunan University Changsha 410082 China2. Department of Computer Science Lakehead University Thunder Bay P7B 5E1 Canada3. Mathematics and Information Science College Hebei Normal University Shijiazhuang 050016 China

By researching on the node scheduling problem of m-covered and connected sensor networks,a new concept of two-hops-cluster is proposed in this paper,and based on it,a new distributed node scheduling algorithm THCNS for allocating all nodes in the sensor network into k(k≤m) different groups {0,1,...,k 1} is designed,without requiring location *** algorithm guarantees that each group to be connected and maintains the coverage ratio with high *** analysis and simulation results show that it has better performance than previous randomized scheduling scheme,and can prolong the lifetime of the sensor network effectively.

关键词： node scheduling lifetime wireless sensor network two-hops-cluster

The new interpretation of support vector machines on statistical learning theory

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science china Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2 & DENG NaiYang 3,1 School of Information, Renmin university of china, Beijing 100872, china 2 Research Center on Fictitious Economy and Data science, Chinese Academy of sciences, Beijing 100080, china 3 college of science, china agricultural university, Beijing 100083, china 1. School of Information Renmin University of China Beijing 100872 China2. Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing 100080 China3. College of Science China Agricultural University Beijing 100083 China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

Some Properties of Cauchy-Type Singular Integrals in Clifford Analysis

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Journal of Mathematical Research with Applications 2012年第2期32卷 189-200页

作者： Heju YANG 1,2,Yuying QIAO 1,Sha HUANG 1 1.college of Mathematics and Information science,hebei Normal university,hebei 050016,P.R.china 2.college of science,hebei university of science and Technology,hebei 050018,P.R.china college of Mathematics and Information science Hebei Normal University Hebei 050016

First,we give a module estimation of the singular integral with a differential *** by proving the existences of Cauchy principal value we obtain the transformation formula of the Cauchy-type singular integrals with a ... 详细信息

关键词： Clifford analysis Cauchy principal value Cauchy-type singular integral with a parameter transformation formula.

EST-derived microsatellites in P seudosciaena crocea and their applicability to related species

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Acta Oceanologica Sinica 2010年第6期29卷 83-91页

作者： YE Hua WANG Xiaoqing GAO Tianxiang WANG Zhiyong college of animal science and Technology Hunan Agricultural University Changsha 410128 China Key Laboratory of science and Technology for Aquaculture and Food Safety Fisheries College/Fisheries Biotechnology Institute Jimei University Xiamen 361021 China Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 China

Simple sequence repeat （SSR） markers were obtained for the large yellow croaker Pseudosciaena crocea using 1 205 expressed sequences tags （ESTs） from the NCBI *** for 48 ESTSSR loci were designed and screened with 30 *** specimens captured from Guanjingyang sea area in Fujian Province of *** of the loci were polymorphic,which were amplified with 3 to 11 alleles per locus and the mean of *** observed and expected heterozygosity per locus ranged from 0.091 to 0.844 （mean 0.544） and from 0.118 to 0.892 （mean 0.644）,*** information content （PIC） ranged from 0.115 to 0.866 （mean 0.593）.The results for cross-species amplification of the 16 large yellow croaker EST-SSRs on ***,***,***,*** and *** revealed that 14,12,11,7 and 6 loci were successfully amplified with 1 to 10 alleles with an average of 4.5 per locus,respectively,which are suitable for population genetics studies of these species and useful for phylogenetic relationship analysis among these ***,this study provides a set of type I markers for population genetics studies and genome mapping for large yellow croaker and its closely related species.

关键词： Pseudosciaena crocea EST-SSRs genetic diversity cross-species amplification

Microstructure and formation mechanism of twins of laths of austenite with high nitrogen

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science china(Technological sciences) 2007年第6期50卷 755-764页

作者： WU CuiLan1,2 & LUO ChengPing2 1 Center for High Resolution Electron Microscopy, college of Materials science and Engineering, Hunan university, Changsha 410082, china 2 college of Mechanical Engineering, South china university of Technology, Guangzhou 510641, china 1. Center for High Resolution Electron Microscopy College of Materials Science and Engineering Hunan University Changsha 410082 China 2. college of Mechanical Engineering South China University of Technology Guangzhou 510641 China

The microstructure of composite diffusion layer of the nitrided and chromized 0.2% carbon steel is investigated using TEM and EDS. It is found that laths of austenite with high nitrogen (γ N) precipitate from α-ferrite matrix in the deeper zone of the diffusion layer. These γ N laths are all twins, with their {111} twinning planes parallel to the lath axis, thus forming a characteristic "back-to-back" morphology. There are two types of γN lath. The first is a genuinely {111} twin, and γ N and α keep the accurate K-S relationship, and each γ N and α form a sharp and smooth γ N/α inter- face of {335}γN//{341}α, namely habit plane {335}fcc. The second is a pseudo-twin, with micro-twins {111} or faults formed within the two twin components. Localized lattice deformation (relaxation) seems to have occurred at the interfaces of the second type of γ N due to the formation of micro-twins or faults within the twin components. These micro-twins or faults make the orientation relationship (OR) between each of the γN and the α-matrix deviate from the accurate K-S OR, and the OR between two γ N twin components deviate from the genuine {111} twin relation- ship. In addition, the γ N/α interface of the second type of γ N is not as sharp or smooth as that of the first one.

关键词： austenite containing nitrogen, twins, steel 20, nitriding, composite chromizing

小麦与叶锈菌互作过程中细胞程序性死亡的生化证据(简报)

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实验生物学报 2004年第4期37卷 329-332页

作者：白志英王冬梅侯春燕韩胜芳河北农业大学园林与旅游学院保定071001 河北农业大学生命科学院保定071001

细胞程序性死亡(Programmed Cell Death,PCD)是一种受基因调控的、主动的、连续的程序化反应.一般发生程序性死亡的细胞具有较为典型的形态及生化特征:细胞收缩、核染色质浓缩、趋边化;DNA在一定位点被核酸内切酶降解成以180bp为基数的... 详细信息

细胞程序性死亡(Programmed Cell Death,PCD)是一种受基因调控的、主动的、连续的程序化反应.一般发生程序性死亡的细胞具有较为典型的形态及生化特征:细胞收缩、核染色质浓缩、趋边化;DNA在一定位点被核酸内切酶降解成以180bp为基数的片段,在琼脂糖凝胶电泳中呈现"梯"状条带(DNA Ladder),即:DNA片段化[1,2]等.近年来,随着植物细胞程序性死亡的研究进展,人们逐渐认识到细胞程序性死亡不但是植物正常发育中必不可少的组成部分[3-5],而且是植物抵抗病原体侵染的重要机制.

关键词：小麦叶锈菌细胞程序性死亡 DNA 基因