Fuzzy modelling of static system optimum traffic assignment problem having multi origin-destination pair

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.     

When to accept a sequence of gambles

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.     

Probability theory in fuzzy sample spaces

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.     

基于三角模糊数比较大小原理的模糊层次分析法在供应商合作伙伴选择中的应用

提出了一种基于三角模糊数比较原理的供应商评价指标体系和多级评价模型，根据模糊层次分析法建立决策递阶层次结构，再依据三角模糊数比较原理隶构建多级评价模型，通过实证分析说明了该模型在供应商评价方面的有效性.     

有界灰数空间的完备性可分性与局部紧性

本文首先指出有界灰数对于四则运算不具备封闭性。证明了有界灰数所构成的空间(G(?),D)是可分的,局部紧的完备度量空间。     

Measuring Labour Services: Quality‐Adjusting the Entry and Exit of Workers

Many statistical agencies use the sum of hours worked when measuring labour services. This implies that all workers provide work of equal quality. Various indices for adjusting for labour quality have been employed in a large body of literature. However, this literature has not yet addressed the issue of how to quality‐adjust the impact of workers entering and exiting the labour market. We outline a theoretical framework for dealing with quality adjustment of labour services caused by workers entering and exiting employment. To illustrate the theoretical framework, we use the case of Norway in the period 1997–2013. The impact on labour services due to our quality adjustment of net entry is found to be cyclical. While the adjustment for the quality of net entry amounts to about −0.3 percentage points annually during expansions, it is offset by about the same magnitude during contractions.     

Volatility and stock price indexes

The stochastic approach to index numbers has been successfully applied to the estimation of inflation, the world interest rate and international competitiveness.?One distinct advantage of this approach is that it provides the whole distribution of the index, not simply one value. In this article, we extend the stochastic approach to the estimation of a stock market index. We demonstrate how this approach can be used to identify ‘redundant stocks’ that do not contribute significantly to the overall index.?For index tracking purposes, these stocks can be safely excluded.     

Quality of service and segmentation in the MICE industry: An approximation based on fuzzy logic

This article aims to evaluate the service quality experienced at academic conferences held at the Universidad Técnica Particular de Loja in Ecuador. Our approach is based on fuzzy logic and ideal solutions to calculate a global attendee satisfaction index for specific market segments: Gender, nationality, and age. Current literature on the service quality experienced by conference attendees is still scarce. Our results show that the analyzed segments experience varying levels of satisfaction, and that the more influential attributes to each of them are also different. Our results can be applied to improve the competitiveness of Loja and that of Universidad Técnica Particular de Loja.     

双差数列的几个性质

讨论了双差数列与周期双差数列的通项公式以及求和公式。     

Stochastic growth: asymptotic distributions

Summary. This note studies conditions under which sequences of state variables generated by discrete-time stochastic optimal accumulation models have law of large numbers and central limit properties. Productivity shocks with unbounded support are considered. Instead of restrictions on the support of the shock, an “average contraction” property is required on technology. Received: August 27, 2001; revised version: January 9, 2002 RID="*" ID="*"The author thanks John Creedy and Rabee Tourky for helpful comments, and the Economic Theory Center, University of Melbourne for financial support.