Suna Kondakci

A flexible flowshop problem with total flow time minimization

Abstract In this study, we consider total flow time problem in a flexible flowshop environment. We develop a branch and bound algorithm to find the optimal schedule. The efficiency of the algorithm is enhanced by upper and lower bounds and a dominance criterion. Computational experience reveals that the algorithm solves moderate sized problems in reasonable solution times.

Bicriteria scheduling problem involving total tardiness and total earliness penalties

Abstract This paper considers the problem of minimizing the weighted sum of earliness and tardiness penalties on a single machine. A simple and efficient lower bound is developed and several upper bounds are proposed. A branch and bound procedure incorporating the bounds, precedence relations and dominance properties is proposed. An experiment is designed to test the efficiency of the bounds, precedence relations, etc. Computational experience with problems up to 20 jobs is reported.

Single machine scheduling with maximum earliness and number tardy

In this paper, we study the bicriteria scheduling problem of minimizing the maximum earliness and the number of tardy jobs on a single machine. We assume idle time insertion is not allowed. We first examine the problem of minimizing maximum earliness while keeping the number of tardy jobs to its minimum value. We then propose a general procedure for generating all efficient schedules for bicriteria problems. We also develop a general procedure to find the efficient schedule that minimizes a composite function of the two criteria by evaluating only a small fraction of the efficient solutions. We adapt the general procedures for the bicriteria problem of minimizing maximum earliness and the number of tardy jobs.

An efficient algorithm for the single machine tardiness problem

Abstract This study considers the problem of minimizing total tardiness on a single machine. A simple and efficient lower bound and several upper bounds are developed. A branch and bound procedure incorporating the bounds, precedence relations and dominance properties is proposed. An experiment is designed to test the efficiency of the bounds, precedence relations and the branch and bound procedure. Computational experience with problems up to 35 jobs is reported.

Note: Bicriteria scheduling for minimizing flow time and maximum tardiness

We consider the bicriteria problem of minimizing total flow time and maximum tardiness penalties for a given set of jobs on a single machine. We develop an algorithm that finds the optimal schedule for any given monotonic function of the two criteria by generating only a small subset of the efficient schedules.

Scheduling with bicriteria: total flowtime and number of tardy jobs

Abstract In this paper the problem of minimizing total flowtime and number of tardy jobs on a single machine is considered. Some properties of the nondominated solutions are discussed. Computational results on the usefulness of developed properties for problems having up to 30 jobs are reported.

Bicriteria Scheduling: Minimizing Flowtime and Maximum Earliness on a Single Machine

We consider the bicriteria problem of minimizing total flowtime and maximum earliness penalties for a given set of jobs on a single machine. We discuss some properties of the efficient solutions and develop a heuristic procedure to generate all efficient solutions when inserted idle time is not allowed.

Scheduling of Unit Processing Time Jobs on a Single Machine

In this paper we address the scheduling problem of unit processing time jobs on a single machine considering number of tardy jobs and a measure of earliness. We consider total absolute lateness, total earliness and maximum earliness, as earliness measures.

Scheduling unit-time tasks in renewable resource constrained flowshops

In this paper we address the problem of scheduling unit time jobs in a flowshop to minimize makespan under a discrete renewable resource constraint. We propose algorithms having complexityO(n) for special cases of two machine and three machine problems. For the three machineN P-hard problem we develop a branch and bound procedure and several upper and lower bounds. We test the efficiency of the procedure and report our computational experience.

An interactive approach for a dual-constraint job shop scheduling problem

Abstract Until recently, heuristic dispatching rules were the only practical means to solve the job shop scheduling problem. Currently, a promising direction in job shop scheduling is interactive scheduling. In this study an interactive scheduling approach is developed for a dual-constraint dynamic job shop production environment. The approach is used by a number of subjects in an experiment. The performance of the subjects is compared with that of disptaching rules based on tardiness and other measures relevant to the job shop environment. the results indicate that the subjects outperform the dispatching rules in general.