The Research Of Cost-Benefit Trade-off Models About Capacity Expansion In Networks

In our real life there are many kinds of network, such as urban traffic network, telecommunication network, power generation network and computer network. All these networks play important roles in our economic life and they are the carrier of the country economic growth. During all these years of quick development of Chinese economy, network is going through deep changes. Therefore, research on network optimization is very critical reference for decision makers in real network construction.It is well known that the network optimization model attains great attentions in international research field and there are many aspects of models mentioned. In this dissertation, some models and their corresponding algorithms about cost-benefit trade-offs raised in capacity expansion of network are presented. For, in reality, a certain network's capacity could be limited, when the capacity need be expanded because of increasing demands, the network capacity expansion problem comes up.There are six chapters in this dissertation except the abstract. The first chapter gives the application background of the models, and, also research methods and creative idears in the dissertation is put forward in detail. The second chapter presents research background, including basic models and basic algorithms in network flow theory and capacity expansion models. Chapter three to Chapter five are the main content, in which five main models and some related models are presented and discussed in this part. Last chapter presents the conclusion of the whole dissertation; meanwhile, some future research on models of cost-benefit about capacity expansion is presented.The main models and algorithms are discussed in three chapters. Firstly, it is the research of cost budget models and algorithms in network capacity expansion, which considers two models'capacity expansion strategy under given budget with different assumptions. Secondly, it is about research of optimum cost-benefit trade-off models and algorithms in network expansion. In this part the relationship between benefit function and cost function are discussed, including difference and ratio of two functions. Finally, it presents cost-benefit models and algorithms under stochastic factors. It discusses multi-stage network capacity expansion strategy with stochastic demand, in which demand is uncertain but the probability distribution function is known. There are still many problems worth researching in this field and stochastic conditions get highly attention recently in international literature because of its characteristic is closer to realistic description. The future research in capacity expansion should take more consideration on this aspect.