Angélica Lozano

SHORTEST VIABLE HYPERPATH IN MULTIMODAL NETWORKS

Abstract In this work both the multimodal hypergraph and the viable hyperpath conceptualizations are presented. The shortest viable hyperpath problem (SVHP) in a multimodal transportation network is defined. We consider a label correcting approach to find the shortest viable hyperpath from an origin to a destination, for different values of the upper limit of modal transfers. Such hyperpaths compose a Pareto-optimal set, from where the user could choose the “best” hyperpath according to personal preferences with respect to the expected travel time and the upper limit of modal transfers. An application example on a multimodal network is presented.

An algorithm for the recognition of levels of congestion in road traffic problems

Detection and recognition of the level of congestion at an intersection is a very important problem and a valuable source of information in traffic management. Although it is just one of all the aspects that make up a traffic management system, it seems to be a crucial point for gathering information. In this paper, we present a technique based on a k-means clustering algorithm for classification, which has been already successfully used in a number of pattern recognition problems, namely: as an algorithm for face recognition problems and in a number of medical diagnosis problems and it compares very well with the state of the art techniques.

Inventory service-level optimization in a distribution network design problem using heterogeneous fleet

This paper is an extension of a study that presents a model and a three phases methodology for distribution networks design based on the location-allocation problem (LRP) and the inventory-routing problem (IRP) considering a fleet of vehicles with heterogeneous capacity. The methodology first phase is facilities location, second phase is facilities allocation, and third phase is inventory-routing. In the last phase, the re-order time (T) per facility is obtained, considering a constant level of service (α) for all facilities. In this paper, the problem is modified by aggregating shortage or unfilled demand costs (Pc) to the objective function, and the methodology phase three is modified by including decision variable α. T and α are obtained by the application of two heuristics. In this paper, we show that the inclusion of α as decision variable, improves solution.

Urban Hazmats Line-Haul, Distribution and Modal Change: Case Studies from Mexico

This paper analyzes urban hazmats transportation within very congested and populated urban zones in Mexico. Three case studies are presented: chlorine line-haul transportation within the metropolitan zone of Mexico City (MZMC), gasoline physical distribution within a subzone of the MZMC, and a real accident happened during a modal change of trichloro-s-triazinetrione at the Port of Veracruz City.

Transport network models for routing algorithms

Six techniques to model transport networks for routing algorithms are discussed. Methods are compared in two tables, the main characteristics of the six models are presented in the first table and the strength and weakness of the discussed models are presented in the second table. It was identified that for routing applications on a multimodal transportation network, a set of minimum criteria are required.