Vehicle-Based internal transport systems are widely used in many industrial facilities such as warehouses, distribution centers and production facilities. In most vehiclebased internal transport ...systems, on-line dispatching rules are used to control vehicle movements. Single-attribute dispatching rules, which dispatch vehicles based on one parameter such as the load waiting time, are used popularly in practice. Examples of these rules are modified-first-come-first-serve and nearest-workstation-first rules. Hybrid dispatching rules are more complicated and dispatch vehicles using several parameters and types of vehicle assignments. The major advantage of single-attribute rules is that they are simple and easy to implement in practice, but their performance can be improved. In this research, we propose new dispatching rules and compare their performance with several single-attribute and multi-attribute dispatching rules in literature. Experimental results show that our new dispatching rules are robust and perform very well in general.
In this paper, we study the problem of scheduling and dispatching vehicles in vehicle-based internal transport systems within warehouses and production facilities. We develop and use two rolling ...horizon policies to solve real-time vehicle scheduling problems. To solve static instances of scheduling problems, we propose two new heuristics: combined and column-generation heuristics. We solve a real-time scheduling problem by applying a heuristic to dynamically solve a series of static instances under a rolling horizon policy. A rolling horizon can be seen either as a fixed-time interval in which advance information about loads’ arrivals is available, or as a fixed number of loads which are known to become available in the near future. We also propose a new look-ahead dynamic assignment algorithm, a different dynamic vehicle-scheduling approach. We evaluate these dynamic scheduling strategies by comparing their performance with that of two of the best online vehicle dispatching rules mentioned in the literature. Experimental results show that the new look-ahead dynamic assignment algorithm and dynamic scheduling approaches consistently outperform vehicle dispatching rules.
On-line vehicles dispatching rules are widely used in many facilities such as warehouses to control vehicles' movements. Single-attribute dispatching rules, which dispatch vehicles based on only one ...parameter, are used commonly. However, multi-attribute dispatching rules prove to be better in general. In this study, we introduce new dispatching rules and evaluate their performance compared to several good dispatching rules in literature, using the experimental design of a real case study. The performance criteria are minimizing the average load waiting time while keeping the maximum load waiting time as small as possible and better utilize vehicles. The experiments show that newly introduced hybrid dispatching rule yields the best performance overall.
ES Trabajo final de grado basado en el análisis de requerimientos para un problema concreto para el transporte de productos semielaborados y terminados durante el proceso de producción de los mismos ...en la empresa donde se ejecutan las prácticas y búsqueda de soluciones para el diseño conceptual, de detalle y fabricación de la solución seleccionada y validación del producto en condiciones operativas.
EN Final work of degree based on the analysis of requirements for a specific problem for the transport of semi-finished products and finished during the process of production of the same in the company where the practices are executed and search for solutions for The conceptual design, detail and manufacture of the selected solution and validation of the product under operating conditions.
EN Final work of degree based on the analysis of requirements for a specific problem for the transport of semi-finished products and finished during the process of production of the same in the company where the practices are executed and search for solutions for The conceptual design, detail and manufacture of the selected solution and validation of the product under operating conditions.
ES Trabajo final de grado basado en el análisis de requerimientos para un problema concreto para el transporte de productos semielaborados y terminados durante el proceso de producción de los mismos en la empresa donde se ejecutan las prácticas y búsqueda de soluciones para el diseño conceptual, de detalle y fabricación de la solución seleccionada y validación del producto en condiciones operativas.
