| With the rapid development of economy, the logistics network becomes a focus and animportant part in production and life. There are many classic algorithms for the study on theminimum risk and optimal network in graph theory. However, with the development of thelogistics network and the progress of science and technology, people need to explore newalgorithms for minimum risk and optimal network constantly because one can not adapt to thecurrent requirements now.In light of the particularity of dangerous goods transportation, people need to not onlyconsider the optimization of transmission lines in the perspective of network optimization, butalso pay enough attention to the risk in the process of conveying. Sometimes, the latter ismore important than the former.The problem of network optimization in logistics network becomes complicatedrelatively if the qualification has some lines which are given according to the needs of actualproduction and life. Therefore, the reality asks to explore how to solve te problems of optimallogistics network applying the longest path.Based on minimum risk and the relationship between the optimal network and figure,this dissertation gives a minimum risk and minimum cost algorithm about hazardous materialstransportation and an optimal network algorithm through the given edges respectively. Themain contents in this paper are as follows:(1)About the optimal routes of hazardous materials transportation, it considers all theaffected factors as one characteristic risk function. Meanwhile, all the other constraints aretaken into account. It proposes an optimal algorithm about hazardous materials distributionbased on depth first searching minimum spanning tree. As a result, it arrives at the aim thatthe risk is smaller and the route is more optimal during transporting hazardous materials.Simultaneously, with analyzing the complexity of the algorithm, we confirm that thisalgorithm is more practical and takes a smaller space. At the final part, with an example, itverifies the effectiveness and correctness of algorithm.(2)In a directed network, to solve the question that the optimal network problem throughthe assigned frontier set, under the idea of peak levels, we present a way to change a directednetwork into a new hierarchical network. Combining the principle of breadth-first traversal ofhierarchical network vertices on each floor with the new network, we explore an algorithm for searching out the optimal path through the given edges in a network. Finally an example isused to verify the effectiveness and correctness of the algorithm. |
