Medical Goods Transit Schedule With Stochastic Demands And Travel Times

A satisfactory schedule of medical resource transit schedule can not only promote the medical service quality, but also reduce the operating cost efficiently. In actual operations, many uncertain factors usually lead to obtaining an optimal result difficultly or additional distribution costs. Therefore, the research on medical goods transit schedule under uncertainty environment is of great practical significance.Firstly, this paper used the time-space network technique to describe the medical goods transit procedure as a multiple time-space network model, which included several time-space networks to express the flows of different medical goods in the dimensions of time and space. Meanwhile, we employed the optimization theory and method in the system optimization perspective to construct a deterministic integer programming model. In this model, we systematically consider the inventory capacity constraints, the demand of goods for every time point in all hospital departments, the travel time in the process of medical goods distribution and other constrains.Further, based on the deterministic model, considering the stochastic demand and travel time of medical goods that occur in actual operations, we construct an expected value model about medical goods transit with the stochastic demands and travel times.Finally, a genetic algorithm based on permutations and combinations is developed for the deterministic model; a decomposition-based heuristic is proposed for the stochastic model and a program is developed with the Matlab+CPLEX software. Additionally, we select five departments and three kinds of medical goods based on the actual operations to test the proposed models and solution algorithms in actual operations. And analysis the parametric sensitivity to compare the results of different parameters.