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1.
《Socio》2021
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.
We introduce a new numerical method called the complex Fourier series (CFS) method proposed by Chan (2017) to price options with an early-exercise feature—American, Bermudan and discretely monitored barrier options—under exponential Lévy asset dynamics. This new method allows us to quickly and accurately compute the values of early-exercise options and their Greeks. We also provide an error analysis to demonstrate that, in many cases, we can achieve an exponential convergence rate in the pricing method as long as we choose the correct truncated computational interval. Our numerical analysis indicates that the CFS method is computationally more comparable or favourable than the methods currently available. Finally, the superiority of the CFS method is illustrated with real financial data by considering Standard & Poor’s depositary receipts (SPDR) exchange-traded fund (ETF) on the S&P 500® index options, which are American options traded from November 2017 to February 2018 and from 30 January 2019 to 21 June 2019. 相似文献
3.
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
4.
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
5.
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
6.
作者通过对徐志摩作品特别是《再别康桥》的分析,阐述了徐志摩与康桥之关系,论述了徐志摩的艺术观和艺术追述,以及他对新诗复杂而认真的实践,进而说明了其在中国诗坛的地位。 相似文献
7.
GONG Yan-fen PING Yu-lan 《美中经济评论(英文版)》2008,7(5):59-64
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
8.
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
9.
Ola Hammarlid 《Journal of Mathematical Economics》2005,41(8):974-982
When is a sequence of gambles, which is initially rejected eventually accepted? The eventual acceptance is defined as a pair property between the utility function and the sequences of gambles. A sequence of gambles is accepted when the gambles follow a large deviation principle and the utility function is non-satiated and bounded from below in a certain way. The number of gambles required for acceptance is computed. 相似文献
10.
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