The minimum cost network flow problem, (MCNFP) constitutes a wide category of network flow problems. Recently a new dual network exterior point simplex algorithm (DNEPSA) for the MCNFP has been developed. This algorithm belongs to a special “exterior point simplex type” category. Similar to the classical dual network simplex algorithm (DNSA), this algorithm starts with a dual feasible tree-solu...

O Research (OR) instructors use visualizations to help teach graph algorithms and data structures. Algorithm visualization is an illustration of abstract concepts included in computer algorithms, making use of either static or dynamic (animated) computer graphics. In this paper we present new software that includes an animated demonstration of the uncapacitated primal network simplex algorithm....

We present a new efficient approach for solving the multicommodity flow problem as a sequence of subproblems, each on a very sparse but connected network. We show that each subproblem can be contracted to a problem on a much smaller graph. We then solve these problems using the simplex method. We test the algorithm on benchmark instances, and show its improvement over the usual simplex algorithm.

Various methods have been used to economically design wastewater and stormwater collection systems. In this article, Discrete Differential Dynamic Programming (DDDP) which is a subsection of dynamic programming (DP) was used. For each pipe network, various alternatives such as depth and slope of pipe laying and various diameters could be considered to satisfy hydraulic and engineering constrain...

In this paper, a scheduling problem for Automated Guided Vehicles in container terminals is defined and formulated as a Minimum Cost Flow model. This problem is then solved by a novel algorithm, NSA+, which extended the standard Network Simplex Algorithm (NSA). Like NSA, NSA+ is a complete algorithm, which means it guarantees optimality of the solution if it finds one within the time available....

From the most important issues in the design of large logistics network in times of crisis are providing a timely quick reaction for treating of injured people and the rapid distribution of medicines and medical equipment. In this paper, a multi-objective model is presented that aims to determine the location of transfer points and hospitals to provide timely quick reaction for treating injured...

In this paper, a scheduling problem for automated guided vehicles in container terminals is defined and formulated as a Minimum Cost Flow model. This problem is then solved by a novel algorithm, NSA+, which extended the standard Network Simplex Algorithm (NSA). Like NSA, NSA+ is a complete algorithm, which means that it guarantees optimality of the solution if it finds one within the time avail...