10 November 2004, Volume 22 Issue 0411

    

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工程技术
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  DEVELOPMENT PROSPECTS FOR THE VERY LARGE-SCALE PHOTOVOLTAIC POWER GENERATION AND ITS ELECTRIC POWER SYSTEMS IN CHINA

  HU Xue-hao;ZHOU Xiao-xin;BAI Xiao-min;ZHANG Wen-tao

  . 2004, 22(0411): 4-8.

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  Solar energy photovoltaic power generation is hopeful to be applied in a large amount and possesses an important position in the future energy sources. In this paper, the electric load demand and the energy structure of power generation in the mid 21st century are forecasted, the energy bases for Very Large Scale Photovoltaic (VLS-PV) power generation are preliminarily selected, the operation characteristics of PVpower generation and the adaptability of electric power grid for the VLS-PV power generation are analyzed, the schemes for transmitting large amount of PV power and the economic and technical bottlenecks for applying VLS-PV power generation are discussed. Finally, the measures and suggestions for developing VLS-PV power generation in China are presented.
物理学研究专题
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  VLBI OBSERVATIONS OF SGR A^*: A SUPERMASSIVE BLACK HOLE CANDIDATE AT THE GALACTIC CENTRE

  SHEN Zhi-qiang

  . 2004, 22(0411): 8-11.

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  There is compelling evidence that the extremely compact non-thermal radio source at the center of our Milky Way Galaxy, Sagittarius A^* ( Sgr A^*), is a best known supermassive black hole candidate with a dark mass of 4 million solar masses. Very Long Baseline Interferometry (VLBI) technique, with its high-resolution imaging capability, is proved to be the most powerful tool for probing the region of a few Schwarzschild radii of Sgr A^*. This paper updates the progress in the VLBI observations of Sgr A^*, with the emphasis on the importance of the millimeter and sub-millimeter VLBI observations in the detection of the intrinsic structure of Sgr A^* and in our ongoing effort to search for the structural variability. There is no doubt that Sgr A^* would be the most important target for the future sub-millimeter VLBI experiment to test the General Relativity.
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  PERTURBATION THEORIES OF B MESON DECAYS

  LI Hsiang-nan

  . 2004, 22(0411): 12-15.

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  The large amount of experimental data produced by the B factories have stimulated wide investigations of theories for B meson decays. We briefly induce the recent developments in this field, including QCD-improved factorization, perturbative QCD, and soft-collinear effective theory. We shall compare the fundamental assumptions, the treatments of decay mechanism, and phenomenological predictions among these theories.
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  A FEW DIRECTIONS IN STRING THEORY

  LI Miao

  . 2004, 22(0411): 16-19.

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  A few active directions in string theory are described in this paper, in particular, string cosmology and challenges to theorists posed by recent results in observational cosmology.
论文
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  THEORETICAL EXPLANATIONS FOR THE WEINBERG ANGLE ANOMALY

  DING Yong;MA Bo-qiang

  . 2004, 22(0411): 19-22.

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  Weinberg angle (or weak angle) is so important that it can partly confirm the Standard Model (SM), which has been widely accepted because the predictions in the SM are consistent with the experiment data in the last twenty years. In 2002, the value of Weinberg angle reported by the NuTeV collaboration is different from the world average value measured in other electroweak processes. An extensive attention has been paid to this anomaly, because it would shed light on particle physics whether it can be explained or not within the Standard Model. In order to explain this discrepancy, we obtained the correction to the Paschos-Wolfenstein relation when the distributions of strange quark-antiquark are asymmetric within the SM. In this work, we calculated the asymmetry of strange quark-antiquark distributions in the nucleon by using the light-cone meson-baryon fluctuation model and the chiral quark model and gained similar results. As a result, we found that the correction due to the asymmetry of the strange quark-antiquark distributions can remove the NuTeV anomaly to a great extent, which implies that asymmetric strange-antistrange quark distributions may be a reasonable explanation for the NuTeV defect.
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  THE BEIJING ELECTRON-POSITRON COLLIDER AND ITS SECOND PHASE CONSTRUCTION

  ZHANG Chuang

  . 2004, 22(0411): 23-27.

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  The Beijing Electron-Positron Collider (BEPC) has been well operated for 15 years with many exciting high energy physics and synchrotron radiation research results since it was put into operation in 1989. Aiming at t and Charm physics, the BEPC has become a leading machine in the world in its energy region. In order to keep China’s leading position in the t and Charm physics, Chinese scientists proposed the BEPCII project as the second phase construction of the BEPC. The project was approved by Chinese government at the end of 2003. Like the BEPC, the BEPCII will serve two purposes, i.e. high energy physics and synchrotron radiation. The luminosity of the BEPCII will be two orders of magnitude higher than the present BEPC and its performance of synchrotron radiation operation will also be significantly improved. The performance of the BEPC and progress of the BEPCII as well as their prospect are reported in this paper.
资源与环境
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  ON SUSTAINABLE EXPLOITATION OF MARINE BIOLOGICAL RESOURCES IN CHINA

  LIU Rui-yu

  . 2004, 22(0411): 28-31.

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  Fast development of exploitation of living marine resources of China is reviewed. Over exploitation of the limited resources resulted in decrease of natural stock size, catch per unit effort (CPUE), and production of major fish species which seriously influenced the sustainable exploitation and development of China’s marine fishery industry and the countries construction,as well as the low level of hatchery and grow out techniques and disease control. The existing problems are analyzed and discussed. The suggestions for the sustainable exploitation and development of China’s marine fishery resources were put forward such as: (1) to cut off the number of small fishing boats; (2) to enhance culture technique study and exploitation; (3) to develop resource enhancement techniques and practice in coastal seas; (4) to develop high technique of fishery products processing.
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  THE COMPREHENSIVE REGULATION OF FLOOD CONTROL AND ENVIRONMENT PROTECTION IN CITIES

  WANG Ming-na

  . 2004, 22(0411): 32-34.

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  Longwanmiao has been a major dangerous section of flood control in Wuhan over years. In order to verify reliability and effect, we have conducted river model tests. The change of the flow, velocity, level, the river regime, the channel change of scour and sedimentation provide the scientific groundwork for the scheme choice and decision-making of the project.
论文
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  A STUDY ON ECOTOURISM CONNOTATION BASED ON CONCEPT, PRINCIPLES AND PRODUCTS

  LI Yan-qin

  . 2004, 22(0411): 35-39.

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  Nature reserves play an important role in the evolving challenge of maintaining a sustainable world. Visitors are one of the major causes of ecosystem damage. To ensure the sustainability of these ecosystems, the damage impact of visitors must be managed. First, the theory of visitor management is explored in this paper. Alden suggested a reduction in I occurs when P, V, A and Q are reduced and when W is increased. To reduce the detrimental impact of visitors on protected areas should in order of descending priority: increasing W; reducing A; reducing Q; reducing V; and reducing P. Therefore, education programs aimed at changing visitor behavior might be more effective than solely through use limits. Limiting use is only one of many management options.
绿色管理与绿色经济专题
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  GREEN OPERATION: A PRINCIPAL BUSINESS ADMINISTRATIVE IDEA IN THE FUTURE

  LI Xu;ZHU Dao-li

  . 2004, 22(0411): 40-43.

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  This paper analyzes the changes and development of administrative idea through reviewing the relations among social economic conditions, level of social labor force and management science development. This paper indicates that the development of management theory is close related to the social economic conditions and the level of social labor force. The principal activities of management in companies or enterprises are different from each other at the different stages of management science development. So far, the management activities in companies or enterprises have developed from quantity oriented, quality oriented to service oriented. Along with social economic development, the management activities in companies or enterprises will change from service oriented to environment friendly oriented. Therefore, this paper discusses the basic contents, methods and approaches to implement the Green Operation. This paper points out that under the condition of government regulations and public participation, the idea of cycle economy will become the main activity of Green Operation. The companies or enterprises will fulfill their Green Operation by means of design for environment, recycling and remanufacturing, life cycle analysis and life cycle management, factory location and environment impact assessment, etc.
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  STUDIES ON DEVELOPING FRAMEWORK FOR ASSESSING GREEN PROJECT MANAGEMENT

  ZHI Hai-bo;QIAO Kun;SU Qing

  . 2004, 22(0411): 44-46.

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  This paper reviews key issues about project management in the studies and practices for sustainability research in the past. More specific references are given to developing a new framework for assessing green project management (FAGPM), a systemic, participatory, interdisciplinary and flexible framework for sustainability evaluation. The FAGPM operative structure is a six-step cycle. The first three steps are devoted to the characterization of the project management process, the identification of critical attributes of sustainability and the selection of specific indicators for the environmental, social and economic dimensions of sustainability in project management process. In the last three steps, the information obtained by means of the indicators is integrated through mixed (qualitative and quantitative) techniques and multi-criteria analysis, so as to obtain a valued judgment about the project management process and to provide suggestions and insights aimed at improving its environmental performance.
论文
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  GREEN TRADE BARRIERS AND DEVELOPMENT OF CHINA’S GREEN FOOD

  CHANG Jin-xiong;ZHANG De-yuan

  . 2004, 22(0411): 47-50.

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  Developed countries attach such an importance to food safety that they set up a green trade barrier, which has great influences on the export of China’s agricultural products. This paper analyses the causes of the green trade barrier, points out that developing the green food the way to China’s agricultural development and that China also has some advantages in developing its green food. Finally the author brings forward some suggestions on how to develop the green food.
科研管理
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  WEB-BASED INFORMATION SYSTEMS: NEW APPROACHES TO INFORMATION ACQUISITION AND DECISION SUPPORT

  ZHUANG Yu-liang

  . 2004, 22(0411): 51-53.

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  This phenomenon of information systems as agents of organizational competitive advantage received a big boost at the end of the last century when Web-based information systems started enabling the current rage of e-commerce and e-business. WIS has recently received considerable attention. Starting from the evolution of information systems, this paper introduces the reason of the innovation on conventional information systems. It describes the structure and factors of Web-based information systems and a generic WIS planning framework of WIS. At last it discusses the concept and applications of Web warehouse-the combination of data warehouse and Web technology.
论文
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  THE EVOLVING TRENDS OF BUSINESS PROCESS MANAGEMENT TECHNOLOGY

  CAI Bin;ZHAO Ming-Jian;HUANG Li-Hua

  . 2004, 22(0411): 54-59.

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  Business Process Management (BPM) is one of the most important enterprise management methodologies and supporting technologies, which is evolving continuously from Taylor’s manual process optimization to IT-supported process change management, such as BPR, then to direct process change execution according to on the fly dynamic needs within the whole scope of end-to-end value chain process collaboration, which enabled by emerging Business Process Management System (BPMS) technology based on pi-calculus. A historical review of these process management technologies is proposed, and then some most important trends in BPM fields are analyzed.
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  THE JOIN OF SOCIAL SECURITY SYSTEM BETWEEN THE CITY AND THE COUNTRYSIDE IN THE BACKGROUND OF REFORM ABOUT CHINESE CENSUS REGISTER

  JI Bian-bian WANG Guo-jun

  . 2004, 22(0411): 60-63.

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  With the reform about Chinese census register, the peasant who have migrated into the city would lost basic livelihood ensure. It is important to resolve the social security for the new city’s people in dual different social security systems, Because it is a matter of importance to the living of the many people, to the stability of Chinese society and to the development of Chinese economy and Chinese civilization. In this article, the difference of dual social security systems was analyzed.