Though recent renewed interest in “expressive” temporal planning, as exemplified by PDDL2.1, has led to advances, few such planners to date can guarantee optimality, or even bounded suboptimality, w.r.t. plan makespan. As a step towards improving planners’ awareness of the quality of their plans, we describe three ways of obtaining lower bound functions, i.e., admissible heuristics, for plan ma...

In this paper, we analyze the characteristics of the dynamic job shop scheduling problem when machine breakdown and new job arrivals occur. A hybrid approach involving neural networks(NNs) and geneticalgorithm(GA) is presented to solve the dynamic job shop scheduling problem as a static scheduling problem. The objective of this kind of job shop scheduling problem is minimizing the completion ti...

In this paper the multi-mode resource-constrained project scheduling problem with discounted cash flows is considered. Minimizing the makespan and maximization the net present value (NPV) are the two common objectives that have been investigated in the literature. We apply one evolutionary algorithm named multiobjective particle swarm optimization (MOPSO) to find Pareto front solutions. We used...

The paper presents a metric that is well suited to evaluate online job schedules for massively parallel processors. We point out the disadvantages of commonly used metrics like makespan or machine utilization. We suggest to use the well known total weighted completion time metric with an appropriate selection of job weights and show that this metric exhibits many properties that are similar to ...

We consider the online problem of minimizing the maximum flow-time on related machines. This is a natural generalization of the extensively studied makespan minimization problem to the setting where jobs arrive over time. Interestingly, natural algorithms such as Greedy or Slow-fit that work for the simpler identical machines case or for makespan minimization on related machines, are not O(1)-c...

In the paper we discuss the influence of the route flexibility degree, the open rate of operations and the production type coefficient on makespan. The flexible job-open shop scheduling problem FJOSP (an extension of the classical job shop scheduling) is analyzed. For the analysis of the production process we used a hybrid heuristic of the GRASP (greedy randomized adaptive search procedure) wit...

In multi-cloud environment, task scheduling has attracted a lot of attention due to NP-Complete nature of the problem. Moreover, it is very challenging due to heterogeneity of the cloud resources with varying capacities and functionalities. Therefore, minimizing the makespan for task scheduling is a challenging issue. In this paper, we propose a genetic algorithm (GA) based approach for solving...

We investigate the problems of scheduling n jobs tom = m1+ m2 identical machines where m1 machines are always available, m2 machines have some specified unavailable intervals.The objective is tominimize the makespan. We assume that if a job is interrupted by the unavailable interval, it can be resumed after the machine becomes available. We show that if at least one machine is always available,...

Scheduling-Location (ScheLoc) Problems integrate the separate fields of scheduling and location problems. In ScheLoc Problems the objective is to find locations for the machines and a schedule for each machine subject to some production and location constraints such that some scheduling objective is minimized. In this paper we consider the Discrete Parallel Machine Makespan (DPMM) ScheLoc Probl...