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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.
This paper discusses the specifics of forecasting using factor-augmented predictive regressions under general loss functions. In line with the literature, we employ principal component analysis to extract factors from the set of predictors. In addition, we also extract information on the volatility of the series to be predicted, since the volatility is forecast-relevant under non-quadratic loss functions. We ensure asymptotic unbiasedness of the forecasts under the relevant loss by estimating the predictive regression through the minimization of the in-sample average loss. Finally, we select the most promising predictors for the series to be forecast by employing an information criterion that is tailored to the relevant loss. Using a large monthly data set for the US economy, we assess the proposed adjustments in a pseudo out-of-sample forecasting exercise for various variables. As expected, the use of estimation under the relevant loss is found to be effective. Using an additional volatility proxy as the predictor and conducting model selection that is tailored to the relevant loss function enhances the forecast performance significantly.  相似文献   
3.
从考察企业组织的敏捷性与交易成本的相互关系入手,对企业组织敏捷性的影响因素进行了剖析。详细分析了信息技术(IT)对提高企业组织敏捷性的作用机理。指出IT正是通过降低企业内、外部的交易成本、缩短流程时间、提高人的认识理性、扼制机会主义、促进企业组织结构、决策方式  相似文献   
4.
课程教学质量是高等学校的生命线,学分制模式下,工商管理类专业课程因其本身固有的特性,课程教学质量的提升在较大程度上依托于一个完善的质量监控体系的有效运作,为此高校要采取措施,在内部构建起课程教学质量的监控体系来确保人才培养质量,从而提高办学水平。  相似文献   
5.
The objective of this paper is to determine the best predictor of equity market crashes by focusing particularly on volatility and market liquidity. In finance, volatility has traditionally been regarded as the best measure of market risk. However, this paper shows that the forecast value of market liquidity, in particular our modified calculated market depth, predicts equity market crashes much more accurately than does the forecast values of EGARCH or Implied Volatility.  相似文献   
6.
This paper demonstrates howadditional rents are generated in a fisherycharacterized by intraseasonal variation infish characteristics, including size,condition, and composition. Based on anexpanded conceptual model of the optimalharvest rule, fish characteristics affect preand post harvest production yields and outputprices. A dynamic empirical model, which uses asystem of quality characteristics and anhedonic equation, illustrates the complexrelationships and management choices associatedwith internalizing seafood qualitycharacteristics in a hake fishery. The modelretains the regulated open access managementsystem, but controls intertemporal andintersectoral quotas, production portfolios,and total allowable catch. Results demonstratethat including revenue-side effects frominternalizing fish quality can generatesignificantly greater rents and reduce therelative benefits of increased productionyields. If excluded, bioeconomic models canunderestimate the level of regulatory rentdissipation and overemphasize managementobjectives such as full utilization, whichcould misdirect processing decisions and resultin a suboptimal resource management plan.Implications for data collection,multidisciplinary analysis, and improvements inmarine resource management are discussed.  相似文献   
7.
伴随中国私营经济而发生的私营资本原始积累,对中国的经济社会发展,对加速中国的社会主义现代化建设,是功绩卓著的。中国之所以能在20世纪末达到小康,私营资本原始积累是立下汗马功劳的。在中国今后的全面小康社会建设中私营资本原始积累必将发挥越来越大的功效。  相似文献   
8.
关于旅游管理专业双语教学的实践与思考   总被引:8,自引:0,他引:8  
以桂林旅游高等专科学校旅游管理专业专业课程《旅游企业人力资源管理》实施双语教学的实践为个案,分析了该专业实施双语教学所面临的困难,提出了加强双语教学实践的对策和建议。  相似文献   
9.
该文在深入分析基础力学各相关课程相互关系的基础上,认为基础力学课程的改革,应该优化组合备相关课程内容,减少重复内容,形成新的教学体系;应该在教学手段上注意现代化教学手段与传统教学手段的结合,激发学生的学习兴趣,提高课堂的效率;也强调实验环节的重要性,要注重学生动手能力的培养。  相似文献   
10.
林子 《嘉兴学院学报》2005,17(3):125-127
调查发现女生中只有33.97%对体育课有兴趣,原因是:体育意识不成熟、教材存在重复现象、有严重的心理障碍、没有突破传统的教学方法、课外活动缺乏行之有效的组织管理等。应采取的措施有:明确高校体育教育理念、加强思想教育、改革体育教学模式、合理选择教学内容和方法等。  相似文献   
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