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Carrying Capacity:An Overview

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Chinese Journal of Population,Resources and Environment 2004年第1期2卷 35-40页

作者： Chen Shaofenginstitute of policy and Management science, cas, beijing 100080, china institute of policy and Management science CAS BJ 100080 China

The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment. Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts, the author makes an attempt to describe its origin, connotations, problems, measurement, and at the same time note the latest international progress in this field.

关键词： Carrying Capacity Sustainable Development

THE PRIMAL-DUAL POTENTIAL REDUCTION ALGORITHM FOR POSITIVE SEMI-DEFINITE PROGRAMMING

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Journal of Computational Mathematics 2003年第3期21卷 339-346页

作者： Si-ming Huang(institute of policy and Management, Academy of Mathematics and System sciences, Chinese Academy of sciences, beijing 100080, china) institute of policy and Management Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

In this paper we introduce a primal-dual potential reduction algorithm for positive semi-definite programming. Using the symetric preserving scalings for both primal and dual interior matrices, we can construct an algorithm which is very similar to the primal-dual potential reduction algorithm of Huang and Kortanek [6] for linear programming. The complexity of the algorithm is either O(nlog(X0 · S0/ε) or O(nlog(X0· S0/ε) depends on the value of ρ in the primal-dual potential function, where X0 and S0 is the initial interior matrices of the positive semi-definite programming.

关键词： Positive semi-definite programming Potential reduction algorithms Complexity.

Design of secure operating systems with high security levels

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science in china(Series F) 2007年第3期50卷 399-418页

作者： QING SiHan1,2 & SHEN ChangXiang3 1 institute of Software, Chinese Academy of sciences, beijing 100080, china 2 School of Software and Microelectronics, Peking University, beijing 102600, china 3 institute of Computing Technology, Navy, beijing 100841, china 1. institute of Software Chinese Academy of Sciences Beijing 100080 China 2. School of Software and Microelectronics Peking University Beijing 102600 China 3. institute of Computing Technology Navy Beijing 100841 China

Numerous Internet security incidents have shown that support from secure operating systems is paramount to fighting threats posed by modern computing environments. Based on the requirements of the relevant national and international standards and criteria, in combination with our experience in the design and development of the ANSHENG v4.0 secure operating system with high security level （hereafter simply referred to as ANSHENG OS）, this paper addresses the following key issues in the design of secure operating systems with high security levels： security architecture, security policy models, and covert channel analysis. The design principles of security architecture and three basic security models： confidentiality, integrity, and privilege control models are discussed, respectively. Three novel security models and new security architecture are proposed. The prominent features of these proposals, as well as their applications to the ANSHENG OS, are elaborated. Cover channel analysis （CCA） is a well-known hard problem in the design of secure operating systems with high security levels since to date it lacks a sound theoretical basis and systematic analysis approach. In order to resolve the fundamental difficulties of CCA, we have set up a sound theoretical basis for completeness of covert channel identification and have proposed a unified framework for covert channel identification and an efficient backward tracking search method. The successful application of our new proposals to the ANSHENG OS has shown that it can help ease and speedup the entire CCA process.

关键词： secure operating systems with high security levels architecture security model covert channel analysis

Optimization of mathematical models for thematic maps

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science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2,XU Li3 & CHENG Xi1,4 1 institute of Geographical sciences and Natural Resources Research,Chinese Academy of sciences,beijing 100101,china 2.institute of policy and Management,Chinese Academy of sciences,beijing 100080,china 3 Taishan University,Taian 271021,china 4 Graduate University of Chinese Academy of sciences,beijing 100049,china Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Fundamental study of CO_2 control technologies and policies in china

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science china(Technological sciences) 2008年第7期51卷 857-870页

作者： JIN HongGuang1, ZHANG XiLiang2, GAO Lin1, YUE Li2, HE JianKun2 & CAI RuiXian1 1 institute of Engineering Thermophysics, Chinese Academy of sciences, beijing 100080, china 2.institute of Nuclear and New Energy Technology, Tsinghua University, beijing 100084, china 1. institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

The technical roadmap and policies for CO2 mitigation suitable for china are a common center of attention in the fields of energy, environment, and management science in the country. Emphasizing interaction between technical research and policy research, this work discovers the potential breakthrough in the integrated field. The technical difficulties of recovering CO2 are pointed out, the mechanism of combining CO2 recovery with energy conversion is investigated, and the basic principle for integrating an environmental-friendly energy system is discussed. Moreover, the formulation of a new energy system that can recover CO2 with very low or even zero energy penalty is proposed, while the assessment methodology and model system for the technical roadmap of CO2 emission control are developed. Finally, a new technical roadmap constructing an energy network suitable for china is proposed, which may provide a new way for the development of sustainable energy and environment technologies.

关键词： CO2 capture and storage technical roadmap energy policy

PROBABILITY CRITERION IN INVENTORY SYSTEM WITH VARYING STOCHASTIC DEMANDS

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Systems science and Mathematical sciences 1994年第3期7卷 211-217页

作者： LIU Baoding GU Jifa (institute of Systems science, Academia Sinica, beijing 100080, china)

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关键词： Inventoryl probability criterion varying stochastic demands.

Change of surface cover greenness in china between 2000 and 2010

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Chinese science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4& GONG Peng1,2,31State Key Laboratory of Remote Sensing science, Jointly Sponsored by institute of Remote Sensing Applications of Chinese Academy of sciences,and beijing Normal University, beijing 100101, china 2institute for Global Change Studies & Center for Earth System science, Tsinghua University, beijing 100084, china 3Department of Environmental science, policy and Management, University of California, Berkeley, CA94720, USA 4Graduate University of Chinese Academy of sciences, beijing 100049, china State Key Laboratory of Remote Sensing science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of Chinese Academy of sciences Beijing China institute for Global Change Studies & Center for Earth System science Tsinghua University Beijing China Department of Environmental science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2000 to 2010 and analyzed their change over china in this *** results showed that an increasing trend of NDVI occurred over 66.84% (OLS fitting) or 64.27% (LAD fitting) of china,indicating that china's greenness is increasing ***,desertification of china *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in china could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

Probability Criterion in Inventory System with Bounded Emergency Order

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Systems science and Systems Engineering 1993年第3期3卷 211-217页

作者： LIU Baoding GU Jifa institute of Systems science, Academia Sinica, beijing 100080, P. R. china

In this paper, we consider the inventory system with a bounded emergency order, using a probability criterion. It is shown that there exist two critical numbers x and x such that the optimal emergency order policy is ... 详细信息

关键词： inventory probability criterion regular emergency order.

ANALYSIS OF WARRANTY POLICIES

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Systems science and Mathematical sciences 1997年第1期10卷 50-60页

作者： CHENG Kan (institute of Applied Mathematics Academia Sinica, beijing 100080, china) 中科院应用数学所北京

There are some warranty policies commonly used: (1) Free-replacement warranty policy (FRW). (2) Pro-rata warranty policy (PRW). (3) Combination policies. In this paper) a brief review of policies 1 and 2 as well as some new distribution properties of successive purchase times under the combination policies are given. In addition, a new warranty policy is suggested. Under this policy the failed item within free replacement period [0,W] is subjected to minimal repair. Under certain cost structure, the long run average cost of customers and the profit of producers are analyzed. Finally, some examples are given.

关键词： Warranty policy free-replacement warranty policy pro-rata warranty policy minimal repair life classes