This study was concerned with developing an antiretroviral drug distribution routing system with a goal of improving fleet utilization whilst reducing delivery costs. The system would enhance ARV drug delivery satisfa...This study was concerned with developing an antiretroviral drug distribution routing system with a goal of improving fleet utilization whilst reducing delivery costs. The system would enhance ARV drug delivery satisfaction of patients staying in the Limpopo province of South Africa. A VRP mathematical programming problem was formulated and the Savings Based as well as the Sequential Insertion algorithm was used to solve the problem. A mini program was then developed in Visual Basic.Net software that speeded up the vehicle route determination heuristics. This computer based vehicle routing system gave a total travelled distance of 1302.94 km and a space utilization of 93% as compared to the pigeonhole system which had a total travelled distance of 2874.2 km and space utilization of 86% for the demand of 5384 ARV drug patients. Therefore, the mathematical programming approach is more cost effective and efficient thereby enhancing delivery satisfaction to ARV drug patients in the province.展开更多
Improviag transportation system is essential for all people in each city since transport plays a very important role. Using mathematical programming approach transport problem is an effective way to improve transporta...Improviag transportation system is essential for all people in each city since transport plays a very important role. Using mathematical programming approach transport problem is an effective way to improve transportation system. In this paper, the traffic equilibrium problem （TEP） with a general nonadditive route cost function is studied. We formulate the route cost function for each route as a disutility function, which can evaluate route cost function flexibly and analyze the route toll conveniently. Furthermore, we present the TEP with a nonlinear complementary problem （NCP） formulation. The monotonicity and the existence with the NCP formulation are also given under relative assumptions.展开更多
文摘This study was concerned with developing an antiretroviral drug distribution routing system with a goal of improving fleet utilization whilst reducing delivery costs. The system would enhance ARV drug delivery satisfaction of patients staying in the Limpopo province of South Africa. A VRP mathematical programming problem was formulated and the Savings Based as well as the Sequential Insertion algorithm was used to solve the problem. A mini program was then developed in Visual Basic.Net software that speeded up the vehicle route determination heuristics. This computer based vehicle routing system gave a total travelled distance of 1302.94 km and a space utilization of 93% as compared to the pigeonhole system which had a total travelled distance of 2874.2 km and space utilization of 86% for the demand of 5384 ARV drug patients. Therefore, the mathematical programming approach is more cost effective and efficient thereby enhancing delivery satisfaction to ARV drug patients in the province.
基金supported by the National Natural Science Foundation of China(Grant Nos.71071014,70771005,70631001)the Fundamental Research Funds for Central Universities of China(Grant No. 2009JBM044)
文摘Improviag transportation system is essential for all people in each city since transport plays a very important role. Using mathematical programming approach transport problem is an effective way to improve transportation system. In this paper, the traffic equilibrium problem （TEP） with a general nonadditive route cost function is studied. We formulate the route cost function for each route as a disutility function, which can evaluate route cost function flexibly and analyze the route toll conveniently. Furthermore, we present the TEP with a nonlinear complementary problem （NCP） formulation. The monotonicity and the existence with the NCP formulation are also given under relative assumptions.
