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61.
丁勇 《物流科技》2004,27(1):24-26
物流配送是一个涉及多种影响因素的综合性复杂问题。本文探讨了基于Agent(智能体技术)的物流配送决策支持系统设计,在该系统中的智能体模型中引入学习机制,初步建立了一个具有专家系统特点、可以不断进化的物流配送决策支持系统。  相似文献   
62.
Probability theory in fuzzy sample spaces   总被引:2,自引:0,他引:2  
This paper tries to develop a neat and comprehensive probability theory for sample spaces where the events are fuzzy subsets of The investigations are focussed on the discussion how to equip those sample spaces with suitable -algebras and metrics. In the end we can point out a unified concept of random elements in the sample spaces under consideration which is linked with compatible metrics to express random errors. The result is supported by presenting a strong law of large numbers, a central limit theorem and a Glivenko-Cantelli theorem for these kinds of random elements, formulated simultaneously w.r.t. the selected metrics. As a by-product the line of reasoning, which is followed within the paper, enables us to generalize as well as to bring together already known results and concepts from literature.Acknowledgement. The author would like to thank the participants of the 23rd Linz Seminar on Fuzzy Set Theory for the intensive discussion of the paper. Especially he is indebted to Professors Diamond and Höhle whose remarks have helped to get deeper insights into the subject. Additionally, the author is grateful to one anonymous referee for careful reading and valuable proposals which have led to an improvement of the first draft.This paper was presented at the 23rd Linz Seminar on Fuzzy Set Theory, Linz, Austria, February 5–9, 2002.  相似文献   
63.
Robustness issues in multilevel regression analysis   总被引:8,自引:0,他引:8  
A multilevel problem concerns a population with a hierarchical structure. A sample from such a population can be described as a multistage sample. First, a sample of higher level units is drawn (e.g. schools or organizations), and next a sample of the sub‐units from the available units (e.g. pupils in schools or employees in organizations). In such samples, the individual observations are in general not completely independent. Multilevel analysis software accounts for this dependence and in recent years these programs have been widely accepted. Two problems that occur in the practice of multilevel modeling will be discussed. The first problem is the choice of the sample sizes at the different levels. What are sufficient sample sizes for accurate estimation? The second problem is the normality assumption of the level‐2 error distribution. When one wants to conduct tests of significance, the errors need to be normally distributed. What happens when this is not the case? In this paper, simulation studies are used to answer both questions. With respect to the first question, the results show that a small sample size at level two (meaning a sample of 50 or less) leads to biased estimates of the second‐level standard errors. The answer to the second question is that only the standard errors for the random effects at the second level are highly inaccurate if the distributional assumptions concerning the level‐2 errors are not fulfilled. Robust standard errors turn out to be more reliable than the asymptotic standard errors based on maximum likelihood.  相似文献   
64.
Chi-Yo  Joseph Z.  Gwo-Hshiung   《Technovation》2007,27(12):744-765
Since the year 2000, silicon intellectual property (SIP), which can minimize the gap in ‘design productivity’ that exists with systems-on-chip (SOC), has become one of the most important factors in the development of integrated circuit (IC) products in the SOC era. Although SIP is very important for IC industry development, complicated business, technical as well as legal issues inside SIP transactions have hindered successful transactions and the integration of SIPs into SOCs. Thus, web-based SIP e-Commerce mechanisms, called SIP Malls, have emerged, aiming to resolve complex SIP issues. To maintain its leading position and competitiveness in the World's IC industry, as well as the value added by SOC products in Taiwanese IC firms, the Taiwanese government has developed SIP Malls, using innovation policy tools. However, the Taiwanese SIP Mall industry remains immature. No existing Taiwanese SIP Malls generate a profit or account for a significant share of worldwide SIP transactions. This research will develop an analytical framework for defining an innovation policy portfolio that aims to develop Taiwan's SIP Mall industry, so that it will enhance the value added of SIP Malls and, thus, the nation's competitiveness in the SIP and IC industries, something which already has become one of the Taiwanese government's major concerns. The industry innovation requirements (IIRs) are summarized using the Delphi method. Meanwhile, the major IIRs identified by Decision Making Trial and Evaluation Laboratory (DEMATEL) are introduced. After the IIRs are derived, the relationships between the IIRs and innovation policy tools are derived by Grey relational analysis (GRA). Then, the innovation policy tools are clustered, based upon the Grey grades derived by GRA. Finally, reconfigured innovation policy portfolios are presented for the Taiwanese government's policy definition. The results demonstrate that developing an innovative policy portfolio that includes scientific, technical, educational, public enterprise, information, legal and regulatory, financial, and taxation policy tools will be the most necessary step towards developing Taiwan's SIP Mall industry.  相似文献   
65.
We examine the statistical performance of inequality indices in the presence of extreme values in the data and show that these indices are very sensitive to the properties of the income distribution. Estimation and inference can be dramatically affected, especially when the tail of the income distribution is heavy, even when standard bootstrap methods are employed. However, use of appropriate semiparametric methods for modelling the upper tail can greatly improve the performance of even those inequality indices that are normally considered particularly sensitive to extreme values.  相似文献   
66.
我国房地产投资基金的发展研究   总被引:1,自引:0,他引:1  
杨光斌 《价值工程》2007,26(2):143-145
首先揭示我国发展房地产投资基金(REITs)的意义所在,然后深入分析我国在发展REITs过程中所遇到的问题和障碍,并提出若干政策和建议。  相似文献   
67.
整合产品服务系统——实现循环经济的新途径   总被引:1,自引:0,他引:1  
整合产品服务系统(IPSS)是一种社会组织创新战略,通过将目前仅生产和销售有形产品的相互分离的工业生产与服务体系有机地整合,以比传统生产和消费模式更低的环境代价,有效满足顾客需求。作为对传统商业模式的革命性变革,整合产品服务系统是促进可持续发展和循环经济的有效手段和必由之路。本文讨论其产生的背景,给出其定义和理论框架,介绍其发展历程,以便为我国发展循环经济提供借鉴。  相似文献   
68.
基于GIS的配送车辆调度系统的设计与实现   总被引:2,自引:0,他引:2  
杨华  符卓 《物流科技》2006,29(1):20-23
本文分析了物流配送与GIS的特点和功能,简要介绍了我们所设计开发的基于CIS的配送车辆调度系统。  相似文献   
69.
报废汽车回收体系结构模型研究   总被引:3,自引:0,他引:3  
吴丹  林云  代应 《物流科技》2007,30(3):44-46
报废汽车的回收重用一方面是"生产者责任延伸制"在汽车行业贯彻实施的结果,另一方面来源于再制造环节中蕴藏的丰厚利润的诱导.目前我国回收利用报废汽车的方式比较落后,主要是对原材料进行重用.本文构建了一个由汽车制造商牵头纽建,以功能多样化的回收中心作为中心处理单元的报废汽车回收体系结构模型,以期实现更高层次的回收重用.  相似文献   
70.
以经济增长质量为研究对象,试图对经济增长质量进行定量分析。在对经济增长质量进行定性分析的基础上建立了经济增长质量指标体系,运用模糊数学理论和层次分析法建立经济增长质量的多层次模糊评价模型,并利用该模型对我国的经济增长质量进行了实证分析。经实证分析表明:采用多层次模糊评判理论进行经济增长质量综合评价是合理、可行的。  相似文献   
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