A hybrid flow shop (HFS) is a generalized flow shop with multiple machines in some stages. HFS is fairly common in flexible manufacturing and in process industry. Because manufacturing systems often operate in a stochastic and dynamic environment, dynamic hybrid flow shop scheduling is frequently encountered in practice. This paper proposes a neural network model and algorithm to solve the dyna...

Ideal schedules minimize both maximum completion time and total completion time of jobs. This paper presents polynomial-time algorithms finding ideal nonpreemptive and preemptive two-machine schedules of jobs with arbitrary release dates and precedence constraints and unit-execution-time operations on identical parallel machines, in a flow shop and an open shop. Heretofore, the complexity statu...

Shop scheduling problems are known to be notoriously intractable, both in theory and practice. In this paper we give a randomized approximation algorithm for flow shop scheduling where the number of machines is part of the input problem. Our algorithm has a multiplicative factor of 2(1 + δ) and an additive term of O(m ln(m+ n)pmax)/δ ).

In military manufacturing enterprises, exceptionally high product performance standards are generally met by using heat treatment followed machining. These procedures typically parallel batch-processing (BP) scheduling problems and job-shop problems, respectively. A mixed-integer nonlinear programming model is created to describe the problem with a machine availability constraint, which divided...

This Paper is an attempt to study two stage open shop scheduling problem in which processing time of the jobs are given. The objective of the paper is to obtain an algorithm to minimize the rental cost of the machines in two stage open shop scheduling problem under specified rental policy. A numerical illustration is given to justify the proposed algorithm.

New complexity results are derived. It is shown that the two machine flow shop problem with a single server is NP-hard if either the setup times or the processing times are constant. Furthermore, polynomial algorithms are given for special cases in which both setup times and processing times are constant. Flow-shop problems with a single server are generalizations of classical flow-shop problem...

The paper addresses a problem of optimal staffing in open shop environment. The problem is to determine the optimal number of operators serving a given number of machines to fulfill the number of independent operations while minimizing staff idle. Using a Gantt chart presentation of the problem it is modeled as twodimensional cutting stock problem. A mixed-integer programming model is used to g...

The following two-machine flow-shop scheduling problem is solved. Given jobs are classified into groups, and each machine needs some setup before the first job in a group is started processing. If a job in a group is started its process, all jobs in the group must be finished before a job in another group is processed. Each job may have a specified lag time between machines. Moreover, a series-...

Minimum makespan scheduling of Flow Shops with Multiple Processors (FSMPs), also known as the Hybrid Flow Shop (HFS), is classified as NP complete. Thus, the FSMP largely depends on strong heuristics to develop solutions to makespan scheduling instances. An FSMP consists of m stages wherein each stage has one or more processors through which n jobs are scheduled. This paper presents a heuristic...