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441.
 从“十四五”保护与发展的生态关系角度,探讨了生态保护与绿色发展的十大生态关系,阐述了生态保护和绿色发展中的一系列有关生态关系的生态智慧及生态技术,并对长江、黄河等流域的生态保护和修复提出了相关建议。  相似文献   
442.
Erratum to: J Syst Sci Syst EngDOI: 10.1007/s11518-007-5058-2The presentation of Table 2 in the original version of this article contained a few typos. The corrected Table 2 is given below.  相似文献   
443.
Learning organisation literature has widely discussed the connections between “double-loop” learning and its significance to organisational performance, but paying little attention to tools and systems that can operationalise “double-loop” learning in organisations. This paper investigates the impact of applying a systems approach for service operations design, expressed as the Vanguard Method (Seddon, Freedom from command and control: a better way to make the work work, 2003), in order to activate “double-loop” learning in service organisations. Two case studies were conducted in the banking mortgage operations and adults’ social care services in the UK, using the dimensions of the learning organisation questionnaire (DLOQ), semi-structured interviews, observations, and documents. The findings of the cross-case analysis support the link of applying the Vanguard Method with operationalising “double-loop” learning through three main factors, namely systematic-operations improvement, organisational capacity development, and outside-in mode of work; that are all embedded into the seven dimensions of the DLOQ. The value of this paper is the introduction of a service operations design tool that can activate “double-loop” learning performance in the fast changing knowledge era. It also provides an impetus for service organisations to creatively influence employees’ competencies to effectively improve internal systems.  相似文献   
444.
Engineering and research teams often develop new products and technologies by referring to inventions described in patent databases. Efficient patent analysis builds R&D knowledge, reduces new product development time, increases market success, and reduces potential patent infringement. Thus, it is beneficial to automatically and systematically extract information from patent documents in order to improve knowledge sharing and collaboration among R&D team members. In this research, patents are summarized using a combined ontology based and TF-IDF concept clustering approach. The ontology captures the general knowledge and core meaning of patents in a given domain. Then, the proposed methodology extracts, clusters, and integrates the content of a patent to derive a summary and a cluster tree diagram of key terms. Patents from the International Patent Classification (IPC) codes B25C, B25D, B25F (categories for power hand tools) and B24B, C09G and H011 (categories for chemical mechanical polishing) are used as case studies to evaluate the compression ratio, retention ratio, and classification accuracy of the summarization results. The evaluation uses statistics to represent the summary generation and its compression ratio, the ontology based keyword extraction retention ratio, and the summary classification accuracy. The results show that the ontology based approach yields about the same compression ratio as previous non-ontology based research but yields on average an 11% improvement for the retention ratio and a 14% improvement for classification accuracy.  相似文献   
445.
调节大豆籽粒生育的生理生态因素   总被引:1,自引:0,他引:1  
大豆籽粒是生殖生长时期植株光合产物主要存储库,鼓粒灌浆期籽粒的生长发育以及干物质积累的过程直接影响大豆的产量。因此,研究大豆籽粒的生长发育及其影响因素对提高产量至关重要。影响大豆籽粒生长发育的因素很多,从源库的改变、外界温度、光照、水分供应以及二氧化碳的浓度的影响,酶活性、内源物质含量的调节以及植物激素的调控等方面予以综述。参64。  相似文献   
446.
从人工生命到人工社会--复杂社会系统研究的现状和展望   总被引:28,自引:10,他引:28  
介绍了人工社会研究工作的内容、方法及其思想基础,并对其应用和未来趋势进行展望。文中简述了社会学研究的历史阶段、主要问题和困难,人工生命和人工社会方法的有效性,并着重描述了Epstein和Axtell的工作,以及相应的涌现方法在复杂社会系统研究中的中心作用。本文还讨论了目前对人工社会方法的各种批判意见及其回应。  相似文献   
447.
DECISION MAKING - THE ANALYTIC HIERARCHY AND NETWORK PROCESSES (AHP/ANP)   总被引:25,自引:0,他引:25  
This is the first part of an introduction to multicriteria decision making using the Analytic Hierarchy Process (AHP) and its generalization, the Analytic Network Process (ANP). The discussion involves individual and group decisions both with the independence of the criteria from the alternatives as in the AHP and also with dependence and feedback in the entire decision structure as in the ANP. This part explains the Analytic Hierarchy Process, with examples, and presents in some detail the mathematical foundations. An exposition of the Analytic Network Process and its applications will appear in later issues of this journal.  相似文献   
448.
1. Introduction This is the fourth exposition on theAnalytic Hierarchy Process. It is true thatmany decisions we make subconsciously ariseout of our physical and biological needs andderive from the pressure to survive physically.We also make subconsciou…  相似文献   
449.
The Analytic Network Process (ANP) is a multicriteria theory of measurement used to derive relative priority scales of absolute numbers from individual judgments (or from actual measurements normalized to a relative form) that also belong to a fundamental scale of absolute numbers. These judgments represent the relative influence, of one of two elements over the other in a pairwise comparison process on a third element in the system, with respect to an underlying control criterion. Through its supermatrix, whose entries are themselves matrices of column priorities, the ANP synthesizes the outcome of dependence and feedback within and between clusters of elements. The Analytic Hierarchy Process (AHP) with its independence assumptions on upper levels from lower levels and the independence of the elements in a level is a special case of the ANP. The ANP is an essential tool for articulating our understanding of a decision problem. One had to overcome the limitation of linear hierarchic structures and their mathematical consequences. This part on the ANP summarizes and illustrates the basic concepts of the ANP and shows how informed intuitive judgments can lead to real life answers that are matched by actual measurements in the real world (for example, relative dollar values) as illustrated in market share examples that rely on judgments and not on numerical data. Thomas L. Saaty holds the Chair of University Professor, Katz Graduate School of Business, University of Pittsburgh, Pittsburgh, PA, and obtained his Ph.D. in mathematics from Yale University. Before that he was a professor at the Wharton School of the University of Pennsylvania for ten years. Prior to that he spent seven years at the Arms Control and Disarmament Agency in the State Department in Washington, DC, that carried out the arms reduction negotiations with the Soviets in Geneva. His current research interests include decision-making, planning, conflict resolution and synthesis in the brain. As a result of his search for an effective means to deal with weapons tradeoffs at the Disarmament Agency and, more generally, with decision-making and resource allocation, Professor Saaty developed The Analytic Hierarchy Process (AHP) and its generalization to dependence and feedback, the Analytic Network Process (ANP). He is co-developer of the software Expert Choice and of the software Super Decisions for decisions with dependence and feedback. He has authored or co-authored twelve books on the AHP/ANP. Professor Saaty has also written a number of other books that embrace a variety of topics, including Modern Nonlinear Equations, Nonlinear Mathematics, Graph Theory, The Four Color Problem, Behavioral Mathematics, Queuing Theory, Optimization in Integers, Embracing the Future and The Brain: Unraveling the Mystery of How It Works. His most recent book is Creative Thinking, Problem Solving & Decision Making. The book is a rich collection of ideas, incorporating research by a growing body of researchers and practitioners, profiles of creative people, projects and products, theory, philosophy, physics and metaphysics...all explained with a liberal dose of humor. He has published more than 300 refereed articles in a wide variety of professional journals. He has been on the editorial boards of Mathematical Reviews, Operations Research, Naval Research Logistics Quarterly, Mathematical and Computer Modeling, Socio-Economic Planning Sciences, Applied Mathematics Letters, and several others. He also served as consultant to many corporations and governments.  相似文献   
450.
This article uses data from the 1971 and 2001 Censuses, the 1999-2003 Labour Force Survey and the 1977 to 2002 International Passenger Survey to investigate the migration processes contributing to the age structure and ageing of the UK's overseas-born population. Overall almost half of recent decades' immigrants to the UK emigrate again within five years of arrival, but with large variation by overseas country of birth. Between half and two thirds of the immigrants born in the continental European Union, North America and Oceania emigrate again within five years, while 15 per cent of those born in the Indian subcontinent do so. Significant cumulative emigration more than five years after arrival is seen among earlier immigrants from the Indian subcontinent, the Caribbean Commonwealth and Europe. Large country-of-origin variations in the ratio of pension-age population to working-age population primarily reflect the country composition of immigration streams 30 or more years before.  相似文献   
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