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1.
Traffic congestion is an unpreventable problem to avoid in a transportation network and it has negative effects on traffic accident, time wasting, traffic delay and safety problem. Besides, in transportation networks, drivers do not want to deal with traffic jam while traversing between specified origin-destination pair. Therefore, traffic assignment (TA) is imperative to improve traffic management, transportation safety, time, and cost savings. System Optimum Traffic Assignment Problem (SOTAP) is a kind of TA model which aims to minimize the total system travel time on the network, and satisfies the flow conservation constraints. To model the SOTAP more realistically, the imprecise parameters can be taken as fuzzy. Therefore, in this paper, we focus on converting the conventional SOTAP to a fuzzy quadratic programming problem (QPP) which is named System Optimum Fuzzy Traffic Assignment Problem (SOFTAP). Here, link travel time is expressed with BPR function as generally used in the literature by converting to fuzzy except link-dependent parameters. Thus, the nonlinear objective function of SOFTAP is expressed in terms of fuzzy link flows and fuzzy link travel times. A solution approach from the literature is modified to the reconstructed SOFTAP.  相似文献   
2.
More than 25 years after the German reunification, data show that products/brands from the eastern regions of Germany (“Neue Länder”) still do not have significant shares in the country's western part (“Alte Länder”). To analyze potential reasons for this phenomenon, our current study replicates a previous study that investigated selected attitudes of Alte Länder consumers toward products/brands from the Neue Länder. It is shown that factors such as consumer ethnocentrism, product judgment, willingness to buy, and economic animosity continue to influence consumer behavior and as such our study offers potential explanation for the failure of Neue Länder products/brands in the western regions of Germany.  相似文献   
3.
The American Psychological Association Task Force recommended that researchers always report and interpret effect sizes for quantitative data. However, no such recommendation was made for qualitative data. Thus, the first objective of the present paper is to provide a rationale for reporting and interpreting effect sizes in qualitative research. Arguments are presented that effect sizes enhance the process of verstehen/hermeneutics advocated by interpretive researchers. The second objective of this paper is to provide a typology of effect sizes in qualitative research. Examples are given illustrating various applications of effect sizes. For instance, when conducting typological analyses, qualitative analysts only identify emergent themes; yet, these themes can be quantitized to ascertain the hierarchical structure of emergent themes. The final objective is to illustrate how inferential statistics can be utilized in qualitative data analyses. This can be accomplished by treating words arising from individuals, or observations emerging from a particular setting, as sample units of data that represent the total number of words/observations existing from that sample member/context. Heuristic examples are provided to demonstrate how inferential statistics can be used to provide more complex levels of verstehen than is presently undertaken in qualitative research.  相似文献   
4.
尚梅 《基建优化》2003,24(6):7-8,11
建筑工程资格预审无论对业主还是对承包商都至关重要,根据建筑工程的特点,在目前普遍采用的资格预审评价方法的基础之上,总结了进行资格预审的评价指标体系,并提出了基于模糊数学意见集中排序法的建筑工程资格预审方法。  相似文献   
5.
各向异性厚板固有频率的精确解   总被引:3,自引:0,他引:3  
该文抛弃薄板理论的位移和应力假设,利用矩阵分析和三维弹性动力学理论,导出四边简支各向异性厚板的固有频率方程。该方法可推广应用于各向异性层合板动力分析。  相似文献   
6.
周敏  李建华 《改革与战略》2008,24(10):191-193
知识管理是现代企业管理的重要内容。正确分析和评价企业的知识管理绩效,对于促进企业知识管理、提高企业知识管理水平以及增强企业竞争优势,具有重要的现实意义。文章构建了企业知识管理绩效评价的指标体系,并运用模糊综合评价模型对企业知识管理绩效进行了综合评价。  相似文献   
7.
设计了一个烧结模糊控制系统,进而构建了一个基于模糊控制的自适应脉宽控制器,对煤气阀、换向阀开关时间进行控制;利用模糊控制器的模糊推理能力来实现煤气阀门开度在线调整,以达到优化控制的目的。运行结果表明,这种控制器与常规比值控制器相比可以取得较好的控制效果。  相似文献   
8.
This article classified gas exploration risk on the basis of the characteristics of oil-gas exploration investment projects, which are internal systems risk and external non-systemic risk. It described each classification specifically and introduced the basic principles and mathematical model of the multi-factor hierarchical fuzzy comprehensive judgment in detail, and then researched the conducts the risk of the gas exploration with examples.  相似文献   
9.
徐刚 《物流技术》2007,26(7):121-122,133
应用层次分析方法的思想,从航材保障对第三方物流的要求制定了科学的评价指标体系。结合指标体系利用模糊评价方法,构建了对第三方物流企业的选择模型,对航材保障中的第三方物流企业做出基本的评价,提供了科学的选择方案。  相似文献   
10.
The economic impact of adopting herd health programs for mastitis and reproduction by small-scale dairy producers of Central Thailand was assessed using a policy analysis matrix (PAM). Following a reduction in the incidence of bovine disease on adopter farms, an increase in private net profits is observed. More importantly the social costs of supporting dairy farmers is reduced; the PAM effective protection coefficient was reduced by 35% for mastitis program adopters and by 44% for reproductive program adopters, indicating improved social efficiency of dairy policy. Other indicators of efficiency and policy implications are discussed.  相似文献   
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