We present a new algorithm called A*+BFHS for solving problems with unit-cost operators where A* and IDA* fail due to memory limitations and/or the existence of many distinct paths between same pair nodes. is based on breadth-first heuristic search (BFHS). combines advantages from both algorithms, namely A*'s node ordering, BFHS's savings, algorithms' duplicate detection. On easy problems, beha...

Ant colony optimization algorithm is a heuristic approach for the solution of combinatorial optimization problems. In order to solve continuous optimization models, an ant colony optimization algorithm is designed. Based on this algorithm, two hybrid intelligent algorithms combined with fuzzy simulation and neural network or integral sum approximation are introduced for solving fuzzy expected v...

This paper addresses the problem of minimizing the makespan on a two-stage parallel flow shops with proportional processing times. The problem of scheduling n independent jobs on m proportional parallel flow shops to minimize makespan is known to be NP-hard and hence too difficult to solve in polynomial time. A multiphase heuristic algorithm to minimize the makespan on two proportional parallel...

in this paper, the scheduling problem with nonresumable jobs and maintenance process is considered in order to minimize the makespan under two alternative strategies. the first strategy is to implement the maintenance process on the machine after a predetermined time period and the second one is to consider the maximum number of jobs that can be done with a special tool. we have proposed a new ...

Title of dissertation: HEURISTICS AND PERFORMANCE METAMODELS FOR THE DYNAMIC DIAL-A-RIDE PROBLEM Ying Luo, Doctor of Philosophy, 2006 Directed by: Professor Paul M. Schonfeld Department of Civil and Environmental Engineering Explicit performance models of a transit system are often very useful in facilitating system design, optimization, alternative comparison, and gaining insights into the sys...

this paper addresses the problem of minimizing the sum of maximum earliness and tardiness on identical parallel machines scheduling problem. each job has a processing time and a due date. since this problem is trying to minimize and diminish the values of earliness and tardiness, the results can be useful for just–in-time production systems. it is shown that the problem is np-hard. using effici...

abstract— in this paper we have tried to develop an altered version of the artificial bee colony algorithm which is inspired from and combined with the meta-heuristic algorithm of firefly. in this method, we have tried to change the main equation of searching within the original abc algorithm. on this basis, a new combined equation was used for steps of employed bees and onlooker bees. for this...

With the rapid expansion of the information on the Internet, recommender systems play an important role in terms of trade and research. Recommender systems try to guess the user's way of thinking, using the in-formation of user's behavior or similar users and their views, to discover and then propose a product which is the most appropriate and closest product of user's interest. In the past dec...

Equivalence checking is a common problem in formal software design. It is the process of determining whether two systems are equivalent to each other according to some mathematically defined notion of equivalence. In this paper to improve efficiency we present a procedure, based on heuristic searches, for checking the well-know simulation relation defined by Milner. We use heuristic mechanisms ...