Transportation of products from sources to destinations with minimal total cost plays an important role in logistics and supply chain management. In this article, a new and effective algorithm is introduced for findin...Transportation of products from sources to destinations with minimal total cost plays an important role in logistics and supply chain management. In this article, a new and effective algorithm is introduced for finding an initial basic feasible solution of a balanced transportation problem. Number of numerical illustration is introduced and optimality of the result is also checked. Comparison of findings obtained by the new heuristic and the existing heuristics show that the method presented herein gives a better result.展开更多
A mobile ad hoc network (MANET) is a kind of wireless ad hoc network. It is a self-configuring network of mobile routers connected by wireless links. Since MANETs do not have a fixed infrastructure, it is a chal-lenge...A mobile ad hoc network (MANET) is a kind of wireless ad hoc network. It is a self-configuring network of mobile routers connected by wireless links. Since MANETs do not have a fixed infrastructure, it is a chal-lenge to design a location management scheme that is both scalable and cost-efficient. In this paper, we propose a cooperative location management scheme, called CooLMS, for MANETs. CooLMS combines the strength of grid based location management and pointer forwarding strategy to achieve high scalability and low signaling cost. An indepth formal analysis of the location management cost of CooLMS is presented. In particular, the total location management cost of mobile nodes moving at variable velocity is estimated using the Gauss_Markov mobility model for the correlation of mobility velocities. Simulation results show CooLMS performs better than other schemes under certain circumstances.展开更多
By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile no...By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile node (MN) needs to orderly accomplish two binding updates with the MAP and home agent (HA) when the MN performs inter-MAP mobility. This results in a high signaling cost, thus affecting network performance. To reduce the inter-MAP binding update cost of idle MN in HMIPv6, an optimization scheme based on pointer forwarding with a threshold is proposed. The scheme can reduces the binding update cost of idle MN by using the binding update between MAP to replace several home binding updates. The signaling cost difference is derived by analyzing the cost of the basic scheme and the optimization scheme between two successive sessions. Simulation results show that, the optimization scheme can reduce the binding update signaling cost and improve the network performance as long as a suitable threshold is chosen. The discussions on the sensitivity of tele-parameters are also given.展开更多
文摘Transportation of products from sources to destinations with minimal total cost plays an important role in logistics and supply chain management. In this article, a new and effective algorithm is introduced for finding an initial basic feasible solution of a balanced transportation problem. Number of numerical illustration is introduced and optimality of the result is also checked. Comparison of findings obtained by the new heuristic and the existing heuristics show that the method presented herein gives a better result.
文摘A mobile ad hoc network (MANET) is a kind of wireless ad hoc network. It is a self-configuring network of mobile routers connected by wireless links. Since MANETs do not have a fixed infrastructure, it is a chal-lenge to design a location management scheme that is both scalable and cost-efficient. In this paper, we propose a cooperative location management scheme, called CooLMS, for MANETs. CooLMS combines the strength of grid based location management and pointer forwarding strategy to achieve high scalability and low signaling cost. An indepth formal analysis of the location management cost of CooLMS is presented. In particular, the total location management cost of mobile nodes moving at variable velocity is estimated using the Gauss_Markov mobility model for the correlation of mobility velocities. Simulation results show CooLMS performs better than other schemes under certain circumstances.
基金supported by the Natural Science Foundation of Jiangsu Province (BK2009469)the Fundamental Research Funds for the Central Universities (BUPT2009RC0120)the National Natural Science Foundation of China (60772110)
文摘By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile node (MN) needs to orderly accomplish two binding updates with the MAP and home agent (HA) when the MN performs inter-MAP mobility. This results in a high signaling cost, thus affecting network performance. To reduce the inter-MAP binding update cost of idle MN in HMIPv6, an optimization scheme based on pointer forwarding with a threshold is proposed. The scheme can reduces the binding update cost of idle MN by using the binding update between MAP to replace several home binding updates. The signaling cost difference is derived by analyzing the cost of the basic scheme and the optimization scheme between two successive sessions. Simulation results show that, the optimization scheme can reduce the binding update signaling cost and improve the network performance as long as a suitable threshold is chosen. The discussions on the sensitivity of tele-parameters are also given.