2 research outputs found
New Approach for Solving The Clustered Shortest-Path Tree Problem Based on Reducing The Search Space of Evolutionary Algorithm
Along with the development of manufacture and services, the problem of
distribution network optimization has been growing in importance, thus
receiving much attention from the research community. One of the most recently
introduced network optimization problems is the Clustered Shortest-Path Tree
Problem (CluSTP). Since the problem is NP-Hard, recent approaches often prefer
to use approximation algorithms to solve it, several of which used Evolutionary
Algorithms (EAs) and have been proven to be effective. However, most of the
prior studies directly applied EAs to the whole CluSTP problem, which leads to
a great amount of resource consumption, especially when the problem size is
large. To overcome these limitations, this paper suggests a method for reducing
the search space of the EAs applied to CluSTP by decomposing the original
problem into two sub-problems, the solution to one of which is found by an EAs
and that to the other is found by another method. The goal of the first
sub-problem is to determine a spanning tree which connects among the clusters,
while the goal of the second sub-problem is to determine the best spanning tree
for each cluster. In addition, this paper proposes a new EAs, which can be
applied to solve the first sub-problem and suggests using the Dijkstra's
algorithm to solve the second sub-problem. The proposed approach is
comprehensively experimented and compared with existing methods. Experimental
results prove that our method is more efficient and more importantly, it can
obtain results which are close to the optimal results.Comment: 27 pages, 7 figure
Selective Survey: Most Efficient Models and Solvers for Integrative Multimodal Transport
In the family of Intelligent Transportation Systems (ITS), Multimodal
Transport Systems (MMTS) have placed themselves as a mainstream transportation
mean of our time as a feasible integrative transportation process. The Global
Economy progressed with the help of transportation. The volume of goods and
distances covered have doubled in the last ten years, so there is a high demand
of an optimized transportation, fast but with low costs, saving resources but
also safe, with low or zero emissions. Thus, it is important to have an
overview of existing research in this field, to know what was already done and
what is to be studied next. The main objective is to explore a beneficent
selection of the existing research, methods and information in the field of
multimodal transportation research, to identify industry needs and gaps in
research and provide context for future research. The selective survey covers
multimodal transport design and optimization in terms of: cost, time, and
network topology. The multimodal transport theoretical aspects, context and
resources are also covering various aspects. The survey's selection includes
nowadays best methods and solvers for Intelligent Transportation Systems (ITS).
The gap between theory and real-world applications should be further solved in
order to optimize the global multimodal transportation system.Comment: 12 pages; Accepted: Informatica (ISSN 0868-4952