The scheduling of automatic guided vehicles for the workload balancing and travel time minimi-zation in the flexible manufacturing system by the nature-inspired algorithm

The real-time scheduling of automatic guided vehicles (AGVs) in flexible manufacturing system (FMS) is observed to be highly critical and complex due to the dynamic variations of production requirements such as an imbalance of AGVs loading, the high travel time of AGVs, variation in jobs, and AGV routes to name a few. The output from FMS considerably depends on the effi-cient scheduling of AGVs in the FMS. The multi-objective scheduling decisions for AGVs by nature inspired algorithms yield a considerable reduction throughput time in the FMS. In this paper, investigations are carried out for the multi-objective scheduling of AGVs to simultaneously balance the workload of AGVs and to minimize the travel time of AGVs in the FMS. The multi-objective scheduling is carried out by the application of nature-inspired grey wolf optimization algorithm (GWO) to yield a balanced workload for AGVs and also to minimize the travel time of AGVs simultaneously in the FMS. The output yield of the GWO algorithm is compared with the results of benchmark problems from the literature. The resulting yield of the proposed algorithm for the multi-objective scheduling of AGVs is observed to outperform the existing algorithms for scheduling of AGVs

A Study of Pooled Dispatching Operation for Yard Tractor in Container Terminal

This paper is a study about an efficient arranging system for yard tractors in container terminal. There are several limits, high rate of vacant vehicle and somewhat inefficiency in allocating vehicles, to the present system due to the Single command method. In this paper, therefore, a pooling arranging system, which is able to manage dual or multi command, will be proposed to solve those problems, make its efficiency higher and heighten its productivity by flexible allocating vehicles. Firstly, to do so, an analysis on the existing operations and process of allocating vehicles in container terminal will be mentioned. Secondly, bases of the pooling arranging system will be explained as well. Moreover, the reasons why it has not accepted will be considered even though the bases of the pooling allocating system are fully acceptable and efficient. After those all, a heuristic pooling method will be suggested as a solution to improve the existing system. To conclude, this study will show the propriety of the proposed solution compared to the existing allocating system.제 1 장 서 론 1 1.1 연구 배경 및 목적 1 1.2 관련 문헌 연구 3 1.3 논문의 구성 5 제 2 장 배차 시스템 분석 6 2.1 양하 배차 시스템 6 2.2 적하 배차 시스템 8 2.3 이적 배차 시스템 10 2.4 Pooling 배차 시스템 12 제 3 장 Pooling 배차 규칙과 해법 절차 19 3.1 Pooled Dispatching 문제 정의 19 3.2 Pooled Dispatching 규칙 정의 24 3.3 Pooled Dispatching 해법 절차 32 제 4 장 실험 및 결과 고찰 35 4.1 실험 35 4.2 결과 고찰 42 제 5 장 결론 46 참 고 문 헌 4

Caracterización de un AGV (vehículo guiado automáticamente) en el sistema de manufactura flexible, caso Centro Tecnológico de Automatización CTAI de la Pontificia Universidad Javeriana

Ingeniero (a) IndustrialPregrad

Conception d’un réseau de transport en commun pour le transport des patients sur l’Île-de-Montréal

RÉSUMÉ : La loi 10 a souhaité une nouvelle organisation du système de soins de santé québécois. Elle a engendré en avril 2015 la création de Centres Intégrés (Universitaires) de Santé et de Services Sociaux (CI(U)SSS). Dans ce contexte de centralisation des établissements de santé québécois, nous avons conduit une étude de terrain de l’organisation du transport non urgent des patients entre les établissements de quatre CIUSSSs sur l’Ile-de-Montréal. Cette étude a révélé que ce type de transport, qui représente un enjeu financier et organisationnel important pour les CIUSSSs, peut être optimisé. En effet, ces établissements de santé ont longtemps fonctionné individuellement. Malgré la centralisation administrative effective, la prise de décision concernant l’organisation du transport externe non urgent des patients est encore visualisée à l’échelle de chaque établissement, voire au niveau de chaque unité. Les processus suivis peuvent ainsi varier d’une unité à l’autre d’un même établissement, même si la plupart des problématiques et moyens de transport utilisés sont partagés. Les déplacements actuellement réalisés par les patients de ces CIUSSSs peuvent présenter une certaine régularité, parce qu’ils concernent des traitements réguliers ou des activités mis en place dans l’objectif d’aider les personnes à vivre chez elles autonomes le plus longtemps possible. De plus, l’existence de corridors de service entre certains établissements peut augmenter la fréquence de certains trajets. Homogénéiser l’organisation actuelle du transport externe non urgent des patients pour la centraliser pourrait donc permettre de réduire la part importante du budget qui lui est accordée et d’augmenter la qualité du service proposé aux patients. Suite à ces observations et connaissant les perspectives d’évolution de la population traitée par le système de soins de santé, nous nous sommes demandé si organiser le transport non urgent des patients de ces CIUSSSs à l’aide d’un réseau de transport en commun serait possible et rentable. Un tel réseau devrait être adapté à la condition physique des patients. Majoritairement à mobilité réduite, ils se déplacent en fauteuils roulants et ne peuvent ni circuler pour rejoindre un arrêt du réseau ni subir un transfert de ligne sur leur trajet. La configuration actuelle des véhicules est telle que les routes dessinées devront aussi permettre de servir la demande en respectant la contrainte de Last-In-First-Out (LIFO), que nous introduisons en conception de réseau. La demande actuelle étant très peu dense, nous avons défini un réseau de transport adapté construit zone par zone. Dans chaque zone géographique construite à l’aide d’un double partitionnement des demandes de transport basé sur la densité, nous avons construit des réseaux à deux niveaux. Nous avons d’abord tracé des routes permettant de servir la partie la plus régulière de la demande. Nous avons ensuite autorisé une certaine déviation des routes dessinées pour affecter les patients aux routes du réseau. Au cours des observations terrain qui ont permis de statuer les hypothèses du problème, nous avons constitué et analysé une base de données qui représente les demandes de transports apparues sur une période de vingt-cinq semaines entre avril et septembre 2016. Les tests réalisés à partir de ces demandes ont permis d’apprécier l’influence des paramètres choisis pour le partitionnement de la demande sur les réseaux obtenus et leur réponse quotidienne à la demande. Les résultats montrent que, dans l’organisation actuelle de la demande, l’association de la contrainte de LIFO et de l’interdiction du transfert de ligne est trop forte pour construire un réseau de transport en commun réaliste et financièrement rentable. Les réseaux construits offrent néanmoins une bonne qualité de transport aux patients. Les routes dessinées par la méthode que nous avons choisie permettent aussi de conclure que considérer l’organisation du transport externe non urgent des patients à l’échelle de l’Ile-de-Montréal sous la forme d’un transport à la demande est prometteuse.----------ABSTRACT : In 2015, the 10th law caused a overhaul of the health care system of Quebec. As an example, the health care facilities were consolidated into regional centers called Centres Intégrés (Universitaires) de Santé et de Services Sociaux (CI(U)SSS). In this context, we have led a field study regarding the organization of the external non-emergency patient transport services between the facilities of four CIUSSSs in Montreal. This survey raised that the organization of external non-emergency patient transport services, which is a major issue at both Financial and organizational points of view, can be improved. As a matter of fact, the facilities have been operating on their own for long. Then, despite the consolidation of administrative service is effective, the decision-making concerning the transportation of patients is still processed at the level of each facility, or even separately in the the care units of one place. Those process can then vary from one place to another, even though the means of transport used and the problems faced are common. The demands of transport from the patients of these CIUSSSs can currently occur on a regular basis, since they are raised by regular treatments or activities aimed at making them be able to live at home independently as long as they can. Furthermore, service corridors exist between several health care centers that can increase some trips frequency. In view of this, standardizing the existing organization of the external non-emergency transportation of patients could help reducing the major part of the budget currently dedicated to this field, and to improve the quality of the service offered to the patients. Considering this and the expected evolution of the patient population, we wondered if a transit network could profitably and suitably be designed to answer the demand of transportation in these CIUSSSs. Such a network should be adapted to the physical and psychological conditions of the patients. Most of them are persons with reduced mobility, then move in wheelchairs and can neither join a stop of the network nor accept any transfer between lines during their travel. Presently, the configuration of the vehicles enforce a Last-In-First-Out (LIFO) constraint, which we introduce in network design. Presently, the demand of transport is really sparse. We then decided to build our network per zone. In each geographical zone defined by a two-level density clustering of the demands, we designed two-level networks. First, we drew routes aimed at answering the most regular demands. Second, we allowed a certain deviation of these routes for the network to serve more demands. Throughout the field study aimed at defining the problem, we gathered a data basis which reflects the transportation demands that occurred over a period of twenty-five weeks between April and September 2016. The experiments allowed us to assess how the parameters chosen influence the network designed and their ability to respond to the daily demand for transports. The results show that under the current organization of the demands of transport, adding the LIFO constraint and avoiding every transfer between lines makes difficult, if not impossible, the design of a realistic and profitable network. Nevertheless, the networks designed offer a very good quality service to the patients. From the routes drawn by the method we have chosen, we can also conclude that considering the organization of the external non-emergency transportation of patients at the level of a whole region as a demand-responsive transport problem could show promise