Significance of Transportation Network Models in Emergency Planning of Cities

Abstract

Transportation network models within the framework of operations research have been established as one of the emerging field of research frontiers in today's very disastrous life and dense traffic system. The discrete as well as continuous flow over time models have been widely considered by social, engineering and applied scientists with wide varieties of real-life problems, like rush hour traffic and traffic management at the time of any disaster. Among the PPRR classification issues, the concentration will be given within the planning approach with transportation networks for urban cities.We present the models and solution strategies of the transportation networks that are dynamic in nature and directly apply in rush hour traffic or human-made or natural disasters in the urban cities. The difficulty levels of the varieties of algorithms, efficiencies of their solution software and the significance of the obtained solutions for the betterment of modern city plan are discussed with wide spectrum of model diversity. Among many others, we illustrate, also supporting with a case study, the impact of recent Nepal Earthquake 2015 and the meaningfulness of effective evacuation planning for saving the property and people in urban city like, Kathmandu, valley.The high performance of the technique of lane reversals in transportation or evacuation networks which has already been adopted a lot in practice, but has been analytically studied only recently are focused in this paper. Adopted this dynamic transportation strategy, the flow in the transportation can be doubled, the time can be saved significantly and many transportation arcs can be utilized for logistic supports or for emergency vehicles whenever necessary. Improved results are presented and the importance of integrated models dependent on time and vehicles is explored. The optimal solution thus obtained with contraflow, logistic supports and facility location at appropriate positions of transportation network proves the significance of these models in emergency planning.

Supported Evacuation for Disaster Relief through Lexicographic Goal Programming

“…The model seeks to evacuate people from pick-up points to shelters with limited capacity, and it is multimodal, considering different types of vehicles; dynamic, because people reach the pick up points at different periods along the time horizon; and multi-objective. It is based on the coordination of network flows of vehicles and people, as stated in [35], where there is a collection of evacuation models based in networks flows with discretized time. We also consider shelters with limited capacity, as in the location-allocation model presented by Sherali et al [6], that selects a set of candidate shelters according to the available resources and minimizes the total congestion in a car based evacuation.…”

Generalized Contraflow for Evacuation Planning Problem

“…Some contraflow problems with efficient analytical solution algorithms in different particular networks have been presented in [3,15,16,17,22]. Some special structured network dynamic flow efficient solutions with continuous time settings on the arcs can be found in [4,18,19,20].…”

Transshipment Contraflow on Multi-Terminal Networks

“…Moreover, using the natural transformation of [4], we have computed some contraflow solutions in different particular network by reversing the direction of arcs at time zero in continuous time model with the same complexity as in discrete time model [15,3].…”