We investigate a random network design problem speci…ed by a complete graph with n nodes whose edges have associated …xed costs that are independent random variables, and variable costs associated that are also independent random variables. The objective is to …nd a spanning tree whose total …xed cost plus total variable cost is minimum, where the total variable cost is the sum of variable cost...

today’s, a common problem in cities is increasing delay and reducing the speed of traffic. on the other wise increasing costs of acquisition in urban area are not allow new routes and highways. also construction of new highway or street such as imam ali highway and sadr highway in tehran lead to develop new applications (such as brt lane ,…) and become quickly saturate and less efficient. there...

introduction: hospitals as important sector of health care system has special location in health economic science. increasing of the operational costs in hospital and limitation in financing cause that hospital as an economic firm use cost analysis and prepare effective using of resource and boost productivity. therefore this study was conducted to calculate daily- patient hotel cost in hospita...