Workshop on Computational Optimization, Modelling & Simulation (COMS) Session 4

Time and Date: 10:15 - 11:55 on 8th June 2016

Room: Cockatoo

Chair: Leifur Leifsson

362 Using Computational Fluid Dynamics (CFD) for Blast Wave Propagation under Structure [abstract]
Abstract: In recent years, improvised explosive devices has been an aspect of crusades by terrorist or movements around the world. The blast wave propagation of an explosive detonation can cause disastrous damage on the buildings, vehicles and also injuries to vehicle occupants. Full scale blast tests are expensive and time consuming but by using computational based numerical simulations can virtually predict these wave propagations and minimize the need of experimental testing. Computational fluid dynamics (CFD) is a common tool to do an analysis of free-field blast wave and against structure. This paper presents two different blast analyses; free field air blast and blast loading towards a structure using ANSYS FLUENT software. A high explosive of 1 kg blast peak overpressure data from an experiment has been patched at the specific domain of the symmetry plane. The computed results were found to be in agreement with theoretical and additional experimental data. The verified free field air blast model was expanded to study the blast loading response towards a structure. It was found that developed CFD can be further used to predict the blast wave propagation subjected to the vehicle structures or buildings.
Arif S. M. Sohaimi, Risby M. S.
377 A VNS-based heuristic for solving the vehicle routing problem with time windows and vehicle preventive maintenance constraints [abstract]
Abstract: We address a vehicle routing problem with time windows (VRPTW) that also contains vehicle with preventive maintenance constraints (VRPTW-PM) and propose a MIP mathematical formulation as well as a general variable neighborhood search metaheuristic (VNS) to solve with large instance the problematic situation. First we create a initial solution using Solomon heuristic then we minimize the number of used routes, and then the total travelled distance by all vehicles is minimized. Computational results show the efficiency of the proposed approach.
Amine Dhahri, Anis Mjirda, Kamel Zidi, Khaled Ghedira
384 Simulation on the shock response of vehicle occupant subjected to underbelly blast loading [abstract]
Abstract: Explosion from an anti-tank mines or improvised explosive devices are recognized as one of the lethal threat towards occupants inside an armoured vehicle. The detonation of these threats creates high intensity blast waves that transmitted to the occupant through vehicle structures and seats. Minimizing the occupant’s casualty can be achieved by properly dissipating the shock waves exerted to the vehicle. It is important to distinguish the contributing factors that affect the behavior of the blast wave so that proper reduction on the shock waves can be achieved. In this paper, three factors such as occupant seating height, charge weight placement and the Hopkinson-Cranz blast scaling were studied using numerical simulations. Design of experiment (DOE) was utilized to determine the ranks and interaction between each factor from the most influential on the results to the least effecting towards the results. From the results it was found that the seating position plays a significant role in reduction the shock response towards the finite element dummy model.
Khalis Suhaimi, Risby Mohd Sohaini, Tan Kean Sheng, Victor Feizal Knight
404 A Heuristic Algorithm for Multi-Site Computation Offloading in Mobile Cloud Computing [abstract]
Abstract: Due to limitation of mobile device in terms of battery life and processing power, Mobile Cloud Computing (MCC) has become an attractive choice to leverage this shortcoming as the mobile computation could be offloaded to the cloud, which is so-called \emph{mobile computation offloading}. Existing research on mobile computation offloading considers offloading a mobile computation to a single cloud. However, in the real world a computation service could be provided by multiple clouds and each computation service may have different performance and different prices. Thus, a new and interesting research problem in mobile computation offloading is how to select a computation service for each of the computation tasks of a mobile computation such that the computation time of the mobile computation, the energy consumption of the mobile device and the cost of using the computation services are minimized. This is so called multi-site computation offloading in mobile cloud computing. In this paper we formulate the multi-site computation offloading problem, propose a heuristic algorithm for the multi-site computation offloading problem and evaluate the heuristic algorithm.
Nur Idawati Md Enzai, Maolin Tang