Heavy and uncertain traffic conditions exacerbate the commuting experience of millions of people across the globe. When planning important trips, commuters typically add an extra buffer to the expected trip duration to ensure on-time arrival. Motivated by this, we propose a new traffic assignment model that takes into account the stochastic nature of travel times. Our model extends the traditio...

Title of dissertation: ON FINDING PATHS AND FLOWS IN MULTICRITERIA, STOCHASTIC AND TIME-VARYING NETWORKS Sathaporn Opasanon, Doctor of Philosophy, 2004 Dissertation directed by: Professor Elise Miller -Hooks Department of Civil and Environmental Engineering This dissertation addresses two classes of network flow problems in networks with multiple, stochastic and time-varying attributes. The fir...

W consider a vehicle routing problem with uncertain travel times in which a penalty is incurred for each vehicle that exceeds a given time limit. A traditional stochastic programming approach would require precise knowledge of the underlying probability distributions of random data. In a novel approach presented here, we assume that only rough information on future travel times is available, le...

In this paper, we consider a specific variant of the field service routing problem. It consists in determining vehicle routes in a single period to serve two types of customers: mandatory and optional. Mandatory customers have to be served within a specified time window whereas optional customers may be served (or not) within the planning horizon. For more realism, we assume that service as wel...

Orienteering problems (OPs) are typically used to model routing and trip planning problems. OP is a variant of the well known traveling salesman problem where the goal is to compute the highest reward path that includes a subset of nodes and has an overall travel time less than the specified deadline. Stochastic orienteering problems (SOPs) extend OPs to account for uncertain travel times and a...

The vehicle routing problem with hard time windows and stochastic service times (VRPTWST) introduced by Errico et al. (2013) in the form of a chance-constrained model, mainly differs from other vehicle routing problems with stochastic service or travel times considered in literature by the presence of hard time windows. This makes the problem extremely challenging. In this paper, we model the V...

This paper studies the problem of finding a priori shortest paths to guarantee a given likelihood of arriving on-time in a stochastic network. Such ‘‘reliable” paths help travelers better plan their trips to prepare for the risk of running late in the face of stochastic travel times. Optimal solutions to the problem can be obtained from local-reliable paths, which are a set of non-dominated pat...