The main aim of the present study is to propose a modified harmony search (MHS) algorithm for size and shape optimization of structures. The standard harmony search (HS) algorithm is conceptualized using the musical process of searching for a perfect state of the harmony. It uses a stochastic random search instead of a gradient search. The proposed MHS algorithm is designed based on elitism. In...

The Harmony Search is a relatively new meta-heuristic algorithm for continuous optimization, in which its concept imitates the process of music improvisation. This paper proposes an improved harmony search algorithm called Harmony Search with Adaptive Pitch Adjustment (HSAPA). The adaptive pitch adjustment scheme during a search period is inspired from the velocity clamping in particle swarm op...

In this paper an integrated lot-sizing and scheduling problem in a flexible job shop environment with machine-capacity-constraint is studied. The main objective is to minimize the total cost which includes the inventory costs, production costs and the costs of machine’s idle times. First, a new mixed integer programming model,with small bucket time approach,based onProportional Lot sizing and S...

The power system continuously deals with frequency fluctuations. When a disturbance occurs, the transmission operators rely on underfrequency load shedding (UFLS) scheme to address severe (UF) events maintain at permissible level and prevent blackouts. Defining settings of conventional UFLS is very complex problem due nonlinear nature response, size vast because number UF-relays spread system. ...

The operation of a distribution system in the presence of distributed generation systems has someadvantages and challenges. Optimal sizing and siting of DG systems has economic, technical, andenvironmental benefits in distribution systems. Improper selection of DG systems can reduce theseadvantages or even result in deterioration in the normal operation of the distribution system. DGallocation ...

this article presents the application of two algorithms: heuristic big bang-big crunch (hbb-bc) and a heuristic particle swarm ant colony optimization (hpsaco) to discrete optimization of reinforced concrete planar frames subject to combinations of gravity and lateral loads based on aci 318-08 code. the objective function is the total cost of the frame which includes the cost of concrete, formw...

Many optimization techniques have been proposed since the inception of engineering optimization in 1960s. Traditional mathematical modeling-based approaches are incompetent to solve the engineering optimization problems, as these problems have complex system that involves large number of design variables as well as equality or inequality constraints. In order to overcome the various difficultie...

The Harmony Search (HS) algorithm is a new evolutionary metaheuristic algorithm based on natural musical performance processes that occur when a musician searches for a better state of harmony, such as during jazz improvisation. In the HS algorithm, the solution vector is analogous to the harmony in music, and the local and global search schemes are analogous to musician’s improvisations.The HS...