• Journal of Korea Multimedia Society
• /
• v.18 no.12
• /
• pp.1468-1474
• /
• 2015

Efficient spectrum sharing is an important issue in Device-to-Device (D2D) communications underlaying cellular networks as it can mitigate the interference to cellular users and improve the performance of the systems. In this paper, we formulate the radio resource allocation in D2D communications as a mixed nonlinear integer programing. We show the formulated problem is NP-hard and thus a polynomial time algorithm to solve is not possible. Since such a problem is very hard to obtain the optimal solution within a short running time, we instead propose a fast heuristic suboptimal algorithm to mitigate the interference caused to cellular users and improve the performance of the systems. Simulation results are provided to evaluate the performance of the proposed algorithm.

• Journal of the Korean Society of Safety
• /
• v.13 no.4
• /
• pp.240-247
• /
• 1998

This paper proposed a method for solving the nonlinear integer programing problem to get easily the best compromise solution while holding a nonlinear property by using the genetic algorithms. Also, this paper reported that the optimization problem of systems reliability as was solved by using the preposed method, and the numerical comparison experiments between the 0-1 LP/0-1 NP formulations were demonstrated, and from the quantitative evaluation the efficiency of the proposed method was demonstrated.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.3 no.1
• /
• pp.10-19
• /
• 2002

The purpose of this paper is to describe the design of a general multipurpose batch process or plant in terms of a series of mathematical programing models, and to develop approach solution methodologies. The proposed model for a single period is based on the formulation (MINLP; Mixed Integer Nonlinear Programming) of Papageorgaki and Reklaitis [1], but was linearized (MILP; Mixed Integer Linear Programming) so as to obtain an exact and practical solution, and to allow treatment of uncertainties to be considered in expanding the plant. As a solution strategy a modified Benders' Decomposition was introduced and was tested on three example problems. The optimizing solver, OSL code provided by the IBM Corporation, was used for solving the problems. The solution method was successful in that it showed remarkable reduction in the computing times as compared with the direct solution method.