Congestion in Facilities Location and Layout: Deterministic and Stochastic Models

该项目旨在建立一个共同的理论基础，以模拟在设施位置和设施布局背景下的运动和由此产生的拥堵。其动因源于设施布局和设施选址的两种文献主体总体上是各自独立发展的。目标是通过明确考虑减速、拥堵、流量容量和精确距离，生成一种高级模型，以期在实际应用中提供更好的性能。这项研究工作有三个主要任务。第一个被称为具有广义拥塞区域的平面设施选址问题，该问题通过对障碍（无旅行，无地点）、禁区（无地点）和拥塞区域（无地点，有额外费用的旅行）的共同建模来推进和统一现有的受限设施选址文献。在这个问题的动态/随机版本中，拥堵成本可能随着一天中的时间（表示高峰时段的交通）而变化，或者是一个随机变量。第二个研究任务被称为连接位置问题，其中“连接”用于定义连接不同部门/单元或设施的制造设施或城市流网络的连接部分。该任务的随机版本涉及连接的选择/位置和服务率（以及分配流），以便在考虑拥塞效应的情况下，使固定连接安装成本、排队延迟成本和物料移动成本的总和最小。第三个任务是将研究的理论成果体现在教材中。第一个任务的智力优势在于研究了工厂布局问题，其中工厂不同部分的距离测量不同，并且还在同时允许障碍，禁区和拥挤区域的建模框架中考虑位置问题。第二项任务将允许对通道容量和位置进行建模，并显著增加该领域有限的可用文献。

The project aims at developing a common theory base to model movement and resultant congestion in the context of facilities location and facilities layout. The motivation stems from the fact that the two bodies of literature in facility layout and facility location have generally evolved separately. The objective is to produce a superior class of models that are expected to provide better performance in real-life applications via the explicit consideration of slow-downs, congestion, flow capacity, and accurate distances. The research work has three main tasks. The first one is called the Planar Facility Location Problem with Generalized Congested Regions that advances and unifies existing restricted facility location literature by common modeling of: Barriers (no travel, no location), Forbidden Regions (no location), and Congested Regions (no location and travel with additional cost). In the dynamic/stochastic version of this problem the congestion cost might change with time of day (to represent rush hour traffic) or be a random variable. The second research task is called the Connection Location Problem, where ``connection'' is used to define a connected part of a manufacturing facility or an urban flow network that links different sets of departments/cells or facilities. The stochastic version of this task concerns selection/location and the service rate of the connections (and to assign the flows) so as to minimize the sum of the fixed connection installation costs, the queuing delay cost, and the material movement cost, that take into consideration the congestion effects. The third task is to embody the theoretical results of the study in Educational material.The intellectual merit of the first task is the study the plant layout problem in which distance measures vary in different sections of the plant, and also consider location problems in a modeling framework that simultaneously allows for barriers, forbidden regions and congested regions. The second task would allow for modeling of aisle capacities and placement and add significantly to the limited literature available in this area.