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山地学报 2009年第4期27卷 433-441页

作者：庞家平陈明勇唐建维郭贤明曾荣中国科学院西双版纳热带植物园中国科学院研究生院西双版纳国家级自然保护区科研所

对橡胶-大叶千斤拔复合生态系统和橡胶纯林进行连续3.a的对比观测研究,结果表明在橡胶林里种植大叶千斤拔能促进橡胶生长,橡胶平均基径、平均胸径和平均树高分别比橡胶纯林高出11.0%、9.62%和3.78%。与橡胶纯林相比,混作后土壤含水量的... 详细信息

对橡胶-大叶千斤拔复合生态系统和橡胶纯林进行连续3.a的对比观测研究,结果表明在橡胶林里种植大叶千斤拔能促进橡胶生长,橡胶平均基径、平均胸径和平均树高分别比橡胶纯林高出11.0%、9.62%和3.78%。与橡胶纯林相比,混作后土壤含水量的季节变化较为缓和且旱季含水量较高;且0～10 cm和10～3. cm的土壤容重每年分别约下降0.03.g/cm3.0.01～0.02 g/cm3.随着种植年限的增加,土壤中有机质、全氮、全磷、全钾含量都呈现出先降后升的趋势,而在对照中土壤有机质、全氮、全磷、全钾含量均呈现不断下降的趋势。表明混作后植物的生长及土壤养分状况比橡胶纯林都有所改善。

关键词：农林复合系统土壤水分容重土壤养分

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Study on Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in tropical Area of China

Study on Developing Mechanism of Rubber-tea-chicken Agro-for...

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第三世界生态高峰会

作者： Meng Qingyan~(1 2) Wang Zhaoqian~3.1 Stale Key Laboratory of Remote Sensing science,Jointly Sponsored by the institute of Remeote Sensing Applications of Chinese Academy of sciences and Beijing Normal {3. Beijing 100101,China:2 Center for Spaceborne Remote Sensing Demonstration.national Space Administration,Beijing,100101,China:3.Agro-Ecology Research institute,Zhejiang {3.,Hangzhou 3.0029,China

Developing mechanism of rubber-tea-chicken eco-agricultural model—a typical tropical agro-forestry in Wenchang,Hainan province was studied with *** technology progressing model,stability indicator,as well as harmonizing *** correlation coefficient and producing dominance *** rational mechanism could be mainly induced as:technique promoting function, leverage function of dominance item(livestock husbandry),stability of model structure and harmony of its components,the model pillar product's meeting market need and government's supporting and drawing of favor *** study was aimed at finding out both the rational and the limiting factors in the development of the model and, fnrthermore,putting forward approaches of optimizing the model according to the local situation.

关键词： Mechanism Agro-forestry System Eco-agricultural Model Rubber-tea-chicken

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Land Use and Soil Organic Carbon in China’s Village Landscapes

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Pedosphere 2010年第1期20卷 1-14页

作者： JIAO Jia-Guo YANG Lin-Zhang WU Jun-Xi WANG Hong-Qing LI Hui-Xin E. C. ELLIS Department of Resources and Environmental sciences Nanjing Agricultural University Nanjing210095 （China） institute of Soil science Chinese Academy of Sciences Nanjing 210008 （China） Department of Agronomy and Agroecology China Agricultural University Beijing 100094 （China） Department of Geography ＆ Environmental Systems University of Maryland Baltimore County Baltimore 21250 （USA） Center for Louisiana Inland Water Studies University of Louisiana at Lafayette Lafayette Louisiana （USA）

Village landscapes, which integrate small-scMe agriculture with housing, forestry, and a host of other land use practices, cover more than 2 million square kilometers across China. Village lands tend to be managed at very fine spatial scales （≤ 3. m）, with managers both adapting their practices to existing variation in soils and terrain （e.g., fertile plains vs. infertile slopes） and also altering soil fertility and even terrain by terracing, irrigation, fertilizing, and other land use practices. Relationships between fine-scale land management patterns and soil organic carbon （SOC） in the top 3. cm of village soils were studied by sampling soils within fine-scale landscape features using a regionally weighted landscape sampling design across five environmentally distinct sites in China. SOC stocks across China＇s village regions （5 Pg C in the top 3. cm of 2 ×10^6 km^2） represent roughly 4% of the total SOC stocks in global croplands. Although macroclimate varied from temperate to tropical in this study, SOC density did not vary significantly with climate, though it was negatively correlated with regional mean elevation. The highest SOC densities within landscapes were found in agricultural lands, especially paddy, the lowest SOC densities were found in nonproductive lands, and forest lands tended toward moderate SOC densities. Bue to the high SOC densities of agricultural lands and their predominance in village landscapes, most village SOC was found in agricultural land, except in the tropical hilly region, where forestry accounted for about 45% of the SOC stocks. A surprisingly large portion of village SOC was associated with built structures and with the disturbed lands surrounding these structures, ranging from 〉 18% in the North China Plain to about 9% in the tropical hilly region. These results confirmed that local land use practices, combined with local and regional variation in terrain, were associated with most of the SOC variation within and across China＇s

关键词： agriculture land cover change land use change soil carbon sequestration spatial heterogeneity

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A new prenylated xanthone from the branches of Calophyllum inophyllum

A new prenylated xanthone from the branches of Calophyllum i...

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海南省药学会二○一○年学术年会

作者： Dai-Jing Wei~(a,b),Wen-Li Mei~a,Hui-Ming Zhong~b,Yan-Bo Zeng~a,Xu-Dong Wu~a,Hao-Fu Dai~(a*) a Key Laboratory of tropical Crop Biotechnology,Ministry of Agriculture,institute of tropical Bio{3. and Biotechnology,Chinese Academy of tropical Agricultural {3.s,Haikou 571101,China b College of Chemistry and Molecular Engineering,Qingdao university of {3. and Technology,Qingdao 266042,China

The investigation of chemical constituents from the branches of Calophyllum inophyllum Linn led to the isolation of a new prenylated xanthone,named caloxanthone Q(1),together with three known compounds,2-deprenylrheediaxanthone B(2),jacareubin(3.,and 6-deoxyjacareubin(4).Their structures were completely elucidated on the basis of spectroscopic methods(UV,IR,HR-ESI-MS,1D and 2D NMR).

关键词： Clusiaceae Calophyllum inophyllum Linn Prenylated xanthone Caloxanthone Q

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Visual Analysis for 2-D Point Set Matching

Visual Analysis for 2-D Point Set Matching

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2011 Chinese Control and Decision Conference（CCDC）

作者： Jiaqi Gong is with the institute of Aerospace science and Technology,Shanghai Jiao Tong university,Shanghai,China,on graduate from Huazhong university of science and Technology,Wuhan,China .Hui Ge,Zhongliang Jing is with the institute of Aerospace science and Technology,Shanghai Jiao Tong university,Shanghai,China

This paper presents a theoretically simple,yet efficient approach for the problem of matching the 2-D point sets under rigid motion,where jitter is *** is a fundamental problem in pattern recognition,having applications ranging from robotics to ***,the previous methods tend to use symbolic arithmetic to solve this ***,they are always complex and limited by computational *** this paper,we present a visual analysis for the point set matching problem and develop a geometrical arithmetic which is proven to yield equivalent results to the symbolic *** allows us to view the problem as one of shape matching and obtain an algorithm that firstly generates a probabilistic shape descriptor （PSD） to describe the local geometric property of each point in the point sets,then acquires the local correspondence from the Euclidean distance matrix of the descriptors,and validates the global transformation *** results demonstrate that our simple algorithm with a lower computation complexity effectively improves accuracy over current method,particularly when matching equal-size patterns under varying jitter.

关键词： probabilistic shape generic Fourier descriptor point pattern matching

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Dynamics and Control in a Differential-algebraic Prey-predator Model

Dynamics and Control in a Differential-algebraic Prey-predat...

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2009中国控制与决策会议

作者： Chao Liu~(1,2),Qingling Zhang~2,Jixin Wang~3.1.Department of Information and Computational science,Northeastern university at Qinhuangdao,Qinhuangdao 066004,P.R.China 2.institute of Systems science,Northeastern university,Shenyang 110004,P.R.China 3.Automation Engineering institute,Beijing Vocational College of Electronic science,Beijing,102600,P.R.China

A differential-algebraic model is proposed,which investigates a prey-predator system with stage structure for predator and harvest effort on mature *** using the differential-algebraic system theory and bifurcation theory, local stability of the proposed model around interior equilibrium is ***,instability mechanism of the proposed model due to variation of economic interest of harvesting is *** the purpose of stabilizing the proposed model system around the interior equilibrium,a state feedback controller is ***,numerical simulations are carried out to show the consistency with theoretical analysis.

关键词： Differential-algebraic Model Bifurcation Harvest Effort Economic Interest

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Research on Stability for Discrete-time Switched Linear Singular Systems

Research on Stability for Discrete-time Switched Linear Sing...

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2010 Chinese Control and Decision Conference

作者： Men Bo~(1,2),Yu Xinyang~3.Zhang Qingling~2 1.School of Mathematics and Systems science,Shenyang Normal university,Shenyang 11003. 2.institute of System sciences,Northeastern university,Shenyang 110004 3.Shenyang TV university,Shenyang 110003

The stability of discrete-time switched linear singular(DSLS) systems is studied by using multiple Lyapunov functions and Lyapunov *** existing criteria of stability for discrete-time switched systems are extended into DSLS *** the sufficient conditions of stability for arbitrary switching laws are ***,an illustrative example is proved to demonstrate the applicability of the proposed approach.

关键词： switched systems singular systems stability Lyapunov equations multiple Lyapunov functions

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Regionalization of wheat powdery mildew oversummering in China based on digital elevation

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Journal of Integrative Agriculture 2018年第4期17卷 901-910页

作者： ZOU Ya-fei QIAO Hong-bo CAO Xue-ren LIU Wei FAN Jie-ru SONG Yu-li WANG Bao-tong ZHOU Yi-lin State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Information and Management science Henan Agricultural University Environment and Plant Protection institute Chinese Academy of Tropic Agricultural Sciences/Key Laboratory of Integrated Pest Management on Tropical Crops Ministry of Agriculture institute of Plant Protection Henan Academy of Agricultural Sciences College of Plant Protection Northwest A&F University

Blumeria graminis f. sp. tritici, the pathogen that causes wheat powdery mildew, is one of the most important diseases affecting wheat production in China, and the oversummering is the key stage of wheat powdery mildew epidemic. The more oversummering regionalization of wheat powdery mildew has played an important role in disease prediction, prevention and control. In this study, we analyzed the correlation between oversummering data of wheat powdery mildew and the meteorological factors over the past years, and determined that temperature was the key meteorological factor influencing oversummering of wheat powdery mildew. The average temperature at which wheat powdery mildew growth was terminated(26.2°C) was used as the threshold temperature to regionalize the oversummering range of wheat powdery mildew. This regionalization was done using the GIS ordinary kriging method combined with the Digital Elevation model(DEM) of China. The results showed that annual probability of oversummering region based on Model 26.2 were consistent with the actual survey of the more summer wheat powdery mildew. Wheat powdery mildew oversummering regions in China mainly cover mountainous or high-altitude areas, and these regions form a narrow north-south oversummering zone. Oversummering regions of wheat powdery mildew is mainly concentrated in the high-altitude wheat growing areas, including northern and southern Yunnan, northwestern Guizhou, northern and southern Sichuan, northern and southern Chongqing, eastern and southern Gansu, southeastern Ningxia, northern and southern Shaanxi, central Shanxi, western Hubei, western Henan, northern and western Hebei, western Liaoning, eastern Tibet, eastern Qinghai, western Xinjiang and other regions of China.

关键词： wheat powdery mildew digital elevation model oversummering regionalization geographic information system

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Strategic R＆D Investment:A Game Theoretic Real Options Approach

Strategic R＆D Investment:A Game Theoretic Real Options Appr...

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2009中国控制与决策会议

作者： Yu Dongping institute of national Defense Economy and Management,Central university of Finance and Economics,Beijing 100081

＜正＞This paper applies the theory of option games to discuss the strategic decision rules in corporate R＆D investment under uncertainty and competition,with three uncertainties in terms of income,cost and technology *** results show that there exist both preemptive equilibrium and simultaneous equilibrium in R＆D investment game and exists mixed strategy equilibrium in preemptive equilibrium;and the increase of uncertainty is not always to rise the optimal threshold when considering many uncertain factors which are correlative;reversely,the increase of correlation and hazard rate of R＆D technology will minish the *** analytical result in theory is further verified and enriched by a numerical example at last.

关键词： R&D Investment Decision Real Options Duopoly Option Games

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Multipath Selection of Wireless MD Video Based on AMPSO

Multipath Selection of Wireless MD Video Based on AMPSO

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2011 Chinese Control and Decision Conference（CCDC）

作者： Song Pu,Hong Jiang,HaiYan Zhao Information institute of Southwest university of science and Technology MianYang CN 621010 Information Engineering College, Southwest university of science and Technology

In wireless ad hoc networks,multiple descriptions (MD) coding of video can effectively improve the quality of transmission,but there is a problem that how to choose the optimal *** order to solve the problem,particle swarm optimization algorithm with adaptive mutation (AMPSO) is presented in this paper,which is used to choose transport path of MD *** method can find the optimal solution quickly and effectively by following excellent particles to search the solution space,and introduce adaptive mutation operator to overcome premature *** results show that AMPSO can effectively guarantee the quality of wireless MD video *** average distortion derived from AMPSO reduces at least 0.04,0.13.0.06,and the speed of convergence is increased by 4 times compared with using GA,SAGA and SPTH algorithm to select routing.

关键词： PSO with adaptive mutation Multipath routing Multiple description video Ad hoc

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