| The purpose of CPM network scheduling optimization is to acquire the shortest project duration by adjusting the start time or finish time of each activity under the situation of resource constrains. As quality contral, proceeding management and cost management are the three targets of project management; the network scheduling optimization turns out to be a very important factor during the whole project process from planning period to execution period. Thereby the problem of CPM network scheduling optimization has great value in terms of theory and practice.In order to overcome the difficult point and the shortcoming of the current CPM network scheduling optimization model, this paper analyzes the characteristic of the time floats and extend their applications, research is made to discuss the regularty of transforming the parallel activities into activities chains, which is the essence of the CPM network scheduling optimization. New scheduling optimization methods are presented and the result is also applied on the critical chain theory. The innovative points of the paper are as the following:(1) Great attentios are paid on the net work time floats, their characteristic and application extendments are studied. As time floats represent the characteristics and informations of the whole network, the regularity of the whole network can be discovered by studing that of the time floats. The correlations between the time floats and the path length in the network are the key to discover the regularity of the whole network.(2) Based on the characteristic of the time floats, the project delayed model is created by transforming a group of paralleling activities into an activities chain. on the basis of this model, Varies scheduling methods are designed and applied to solve the network scheduling problems.(3) Based on the characteristic of the time floats, the project delayed model is created by transforming a group of paralleling activities into some activities chains, such as two paralleling chains, or three paralleling chains. On the basis of this model, Varies scheduling methods are designed and applied to solve the network scheduling problems.(4) Applied the time floats regularty on the critical chain theory, the network structure amendments after adding buffers are studied. The CPM network with buffer is designed on this basiss and the chritical chain are transformed into CPm network, the identification of the critital chain, the access chain and the designing of the access poit are studied under the complex CPM network environments. |
