Showing papers on "Flow shop scheduling published in 1983"
TL;DR: A simple algorithm is presented in this paper, which produces very good sequences in comparison with existing heuristics, and performs especially well on large flow-shop problems in both the static and dynamic sequencing environments.
Abstract: In a general flow-shop situation, where all the jobs must pass through all the machines in the same order, certain heuristic algorithms propose that the jobs with higher total process time should be given higher priority than the jobs with less total process time. Based on this premise, a simple algorithm is presented in this paper, which produces very good sequences in comparison with existing heuristics. The results of the proposed algorithm have been compared with the results from 15 other algorithms in an independent study by Park [13], who shows that the proposed algorithm performs especially well on large flow-shop problems in both the static and dynamic sequencing environments.
2,255 citations
TL;DR: A cyclic scheduling method that takes advantage of the flow character of the process and is predicated upon the requirement that during each cycle the shop should perform all of the tasks required to complete a job, although possibly on different jobs.
178 citations
01 Jan 1983
TL;DR: The state of the art of deterministic machine scheduling is reviewed, and emphasis is placed on efficient, i.
Abstract: The state of the art of deterministic machine scheduling is reviewed. Emphasis is placed on efficient, i. e. polynomial-bounded, optimization algorithms. A few of the more significant NP-hardness results are highlighted, and some open problems are mentioned.
161 citations
TL;DR: In this article, the authors explored the due-date performance of job shop control systems which base job due dates on a time-phased representation of the workload and the machine capacity in the shop.
Abstract: This study explores the due-date performance of job shop control systems which base job due dates on a time-phased representation of the workload and the machine capacity in the shop. The performance is measured by the mean and the standard deviation of the lateness. Two parameters are used to vary the functioning of the due-date assignment system: a minimum allowance for waiting, denoted by SL, and a maximum fraction of the available capacity allowed for loading, denoted by CLL. The system increases the waiting lime allowance if congestion is observed when loading a new job. The capability of the system to observe congestion is determined by the parameters CLL and SL.
Simulation experiments are used to investigate the performance of the assignment system. It is shown that the assignment system performs quite well with respect to reducing the standard deviation of the lateness; the performance is not very sensitive however to the parameter values used; with an expected capacity utilization of 90%, CLL should be set between 0.80 and 1.00 times the mean available capacity and SL should be set between 0.55 and 0.90 times the mean operation waiting time in the shop.
The assignment system may also perform well with respect to controlling the mean lateness. If SL is set between 0.55 and 0.75 times the mean expected waiting time in the shop, a constant mean lateness is obtained independent of the utilization of the shop if CLL is set between 0.70 and 0.80 times of the mean available capacity. However, the mean lateness turns out to be quite sensitive to variations in the job-mix of the workload. Finally it is shown that if the values of the assignment parameters are adequate, the mean job lateness is independent of the number of operations in a job. This property can be used to monitor the correctness of the parameter values.
154 citations
TL;DR: A branch-and-bound algorithm for a two-machine scheduling problem by Grabowski is generalized to the case of an arbitrary number of machines and an approach to strengthen these lower bounds is developed.
Abstract: A branch-and-bound algorithm for a two-machine scheduling problem by Grabowski is generalized to the case of an arbitrary number of machines. The lower bounds are obtained by the relaxation of the capacity constraints on the machines. An approach to strengthen these lower bounds is developed. Computational experience with 6-, 10-, 15-, 20-, 30-, 40-, 50-job problems is presented.
77 citations
TL;DR: A concise survey of such resuks is presented in this article with simple proofs based on the ideas of critical paths, non-bottleneck machines, and machine dominance, which covers most previously known special cases and leads to a few new ones as weü
Abstract: — One ofthe earliest results in scheduling theory is an algorithm by S, M. Johnson for scheduling jobs in a two-machine flow-shop to minimize the time at which all jobs are completed. Subsequently, many researchers have efflciently solved special cases of this problem for more than two machines. A concise survey ofsuch resuks ispresented with simple proofs based on the ideas of critical paths, nonbottleneck machines, and machine dominance. This covers most previously known special cases and leads to a few new ones as weü
68 citations
TL;DR: Parallel algorithms are given for scheduling problems such as scheduling to minimizing the number of tardy jobs, job sequencing with deadlines, scheduling to minimize earliness and tardiness penalties, channel assignment, and minimizing the mean finish time.
Abstract: Parallel algorithms are given for scheduling problems such as scheduling to minimize the number of tardy jobs, job sequencing with deadlines, scheduling to minimize earliness and tardiness penalties, channel assignment, and minimizing the mean finish time. The shared memory model of parallel computers is used to obtain fast algorithms.
66 citations
TL;DR: This paper considers the problem of minimizing a linear combination of flow times and max-mum tardiness of a given number of jobs on a single machine and presents a branch-and-bound technique to arrive at an optimal solution.
Abstract: Most scheduling research is done with one criterion; however, the real-world situations demand consideration of multicriterion problems because there are generally many costs associated with scheduling decisions. This paper considers the problem of minimizing a linear combination of flow times and max-mum tardiness of a given number of jobs on a single machine and presents a branch-and-bound technique to arrive at an optimal solution. The computational results are also reported.
65 citations
TL;DR: Surrogate duality bounds for the job shop scheduling problem are obtained by replacing certain constraints by their weighted sum and strengthening the aggregate constraint by iterating over all possible weights.
56 citations
TL;DR: In this article, two simple versions of this two-stage hierarchical scheduling problem are presented, and heuristic solution methods are described and their performance is asymptotically optimal both in expectation and in probability.
Abstract: Certain multistage decision problems that arise frequently in operations management planning and control allow a natural formulation as multistage stochastic programs. In job shop scheduling, for example, the first stage could correspond to the acquisition of resources subject to probabilistic information about the jobs to be processed, and the second stage to the actual allocation of the resources to the jobs given deterministic information about their processing requirements. For two simple versions of this two-stage hierarchical scheduling problem, we describe heuristic solution methods and show that their performance is asymptotically optimal both in expectation and in probability.
49 citations
TL;DR: The results indicate that an assumption of accurately predetermining actual operation times in most cases is not likely to weaken the analysis and impact of research studies which are performed using such an assumption.
Abstract: This study investigates the relative priority of various job shop dispatching rules for various shop utilization levels under both deterministic and stochastic assumptions with regard to processing times The primary criterion for evaluation is that of percentage on time completion The results indicate that an assumption of accurately predetermining actual operation times in most cases is not likely to weaken the analysis and impact of research studies which are performed using such an assumption Also conclusions indicate that the ranking of dispatching rules according to their effectiveness varies significantly with shop utilization levels
01 Jan 1983
TL;DR: ISIS is described, a scheduling system capable of incorporating all relevant constraints in the construction of job shop schedules and both the representation of constraints within ISIS and the manner in which these constraints are utilized in conducting a constraint-directed search for an acceptable schedule are examined.
Abstract: Abstract : Analysis of the job shop scheduling domain has indicated that the crux of the scheduling problem is the determination and satisfaction of a large number and variety of constraints. Schedules are influenced by such diverse factors as due date requirements, cost restrictions, production levels, machine capabilities, operation precedences, resource requirements, and resource availability. This paper describes ISIS, a scheduling system capable of incorporating all relevant constraints in the construction of job shop schedules. The authors examine both the representation of constraints within ISIS, and the manner in which these constraints are utilized in conducting a constraint-directed search for an acceptable schedule. The important issues relating to the relaxation of constraints are addressed. Finally, the interactive scheduling facilities provided by ISIS are considered. (Author)
21 Jun 1983
TL;DR: In this article, the authors describe ISIS, a scheduling system capable of incorporating all relevant constraints in the construction of job shop schedules, and examine both the representation of constraints within ISIS, and the manner in which these constraints are utilized in conducting a constraint-directed search for an acceptable schedule.
Abstract: : Analysis of the job shop scheduling domain has indicated that the crux of the scheduling problem is the determination and satisfaction of a large number and variety of constraints. Schedules are influenced by such diverse factors as due date requirements, cost restrictions, production levels, machine capabilities, operation precedences, resource requirements, and resource availability. This paper describes ISIS, a scheduling system capable of incorporating all relevant constraints in the construction of job shop schedules. The authors examine both the representation of constraints within ISIS, and the manner in which these constraints are utilized in conducting a constraint-directed search for an acceptable schedule. The important issues relating to the relaxation of constraints are addressed. Finally, the interactive scheduling facilities provided by ISIS are considered. (Author)
TL;DR: In this article, the authors define a model that covers the multimachine extensions of all existing flow shop problems with time lags as well as flow-shop problems where setup, processing and release times are separated.
Abstract: This paper defines a model that covers the multimachine extensions of all existing flow-shop problems with time lags as well as flow-shop problems where setup, processing and release times are separated. Approximate solutions and lower completion time bounds are developed for the restricted and unrestricted cases.
TL;DR: In this article, the mean flow-time flow-shop problem is discussed and several new properties have been developed that provide the reader with a better understanding of the model and a class of solvable cases is defined.
Abstract: This paper discusses the mean flow-time flow-shop problem. Several new properties have been developed that provide the reader with a better understanding of this model. A class of solvable cases is defined that includes the known solvable cases.
TL;DR: The algorithm, which is recommended for middle-size problems, is embedded in a dedicated minicomputer-based practical system meant for real time production control in a discrete part manufacturing system environment.
TL;DR: There does not seem to exist any such efficient algorithm to solve an n-job one machine scheduling problem in which processing times are random variables because the problem can be shown to be NP-complete.
Abstract: In 1973, Balut gave an algorithm to solve an n-job one machine scheduling problem in which processing times are random variables and the objective is to minimize the number of tardy jobs with a specified certainty level. This note, however, presents an example for which his algorithm fails to give an optimal schedule. Furthermore, there does not seem to exist any such efficient algorithm because the problem can be shown to be NP-complete.
TL;DR: The results indicate that rules which directly consider costs (or profit) may prove practical for a manager where minimization of WTP and maximization of ROT are the primary and secondary objectives of the company.
Abstract: Although many articles have been published on the general priority scheduling problem, very few have been concerned with directly minimizing costs. The few studies which do consider overall costs do not use these costs in establishing a job's priority in the queue. This paper investigates how the time and cost performance of jobs are affected by the use of a rule which directly considers costs. A simulation model of a hypothetical job shop is used to examine several of these cost rules, as well as some common rules concerned with the timeliness of jobs. Performance measures include both time-oriented and cost-oriented measures. The results indicate that rules which directly consider costs (or profit) may prove practical for a manager where minimization of WTP and maximization of ROT are the primary and secondary objectives of the company
TL;DR: An interactive job shop scheduling program and a new approach to due-date selection which is implemented in the program, which was designed for a labour constrained workshop at the University of Stellenbosch are described.
TL;DR: The proposed method for this problem is based on a new definition of composite jobs and Sidney's theory about series parallel algorithms, and can solve a version of the problem where each job has setup times not included in the processing times and a series-parallel precedence relation is specified among jobs in a group.
Abstract: 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-parallel precedence relation may be specified among groups. Find inter- and intra-group schedules minimizing the total elapsed times on both machines. The proposed method for this problem is based on a new definition of composite jobs and Sidney's theory about series parallel algorithms. The proposed method can also solve a version of the problem where each job has setup times not included in the processing times and a series-parallel precedence relation is specified among jobs in a group.
TL;DR: The experimental study suggests that this efficient linear time algorithm can produce optimal schedules most of the time in the sense that the probability of producing an optimal schedule using this efficientlinear time algorithm is at least 0.9 for over 700 cases randomly constructed in the experiment.
Abstract: In this note we report the results of an experimental investigation on the performance of the very simple level scheduling algorithm for unit time task systems. Although the problem of the construction of optimal k-processor schedules for unit time tasks is NP-complete, the experimental study suggests that this efficient linear time algorithm can produce optimal schedules most of the time in the sense that the probability of producing an optimal schedule using this efficient linear time algorithm is at least 0.9 for over 700 cases randomly constructed in our experiment.
TL;DR: This work presents methods which aim to answer the question of how well permutations perform as strategies in stochastic processing, based on earlier results by Glazebrook.
Abstract: A collection of stochastic jobs is to be processed by a single machine in a manner which is consistent with a precedence relation on the job set. Costs are incurred as jobs are processed and rewards are earned when they complete. The problem of finding optimal processing strategies is in general very complex. However, algorithms exist which in many cases yield the strategies which are optimal among those which are simply permutations of the job set. In light of this, the question of how well permutations perform as strategies is an important one. We present methods which aim to answer this question. They are based on earlier results by Glazebrook.
TL;DR: In this article, the n-job, two-machine flow shop sequencing problem with job processing times following exponential distributions is analyzed and sufficient conditions for determining a job sequence which minimizes a total expected linear cost function are derived.
TL;DR: This paper deals with selecting a heuristic rule for concurrent scheduling of mixtures of due-date and non-due-date jobs and the measure of performance for the mixture of jobs is chosen to be mean flowtime subject to the constraint that due dates are satisfied.
Abstract: This paper deals with selecting a heuristic rule for concurrent scheduling of mixtures of due-date and non-due-date jobs. The measure of performance for the mixture of jobs is chosen to be mean flowtime subject to the constraint that due dates are satisfied. To handle varying levels of due-date tightness, three types of schedules are introduced. Dispatching rules for two of the three types of schedules were selected by simulation. Decision rules for determining the best schedules in appropriate situations are suggested.
TL;DR: The two-machine, minimum-schedule-length case, where both open-shop and flow-shop scheduling problems belong to SP, is proved to be binary TISP-complete under a route-dependent open- shop discipline.
Abstract: Open-shop scheduling, where the processing times of the operations constituting a job depend on the route by which it passes through the machines, is proved to be the master problem of which both open-shop and flow-shop scheduling are special cases. The two-machine, minimum-schedule-length case, where both open-shop and flow-shop scheduling problems belong to SP, is proved to be binary TISP-complete under a route-dependent open-shop discipline. An 0(n) algorithm is presented for a special case of the latter problem with a dominating machine.
TL;DR: This paper analyzes approximation algorithms for two types of scheduling problems and proposes an approximation algorithm for general n/2/F/Lmax and derives its worst case bound.
Abstract: In this paper, we analyze approximation algorithms for two types of scheduling problems. The first is the n jobs scheduling problem with due dates on m identical machines to minimize the maximum lateness. For this problem n/m/I/Lmax, we propose two approximation algorithms and derive their worst case bounds. The second is the 2 x n flow shop scheduling problem with due dates to minimize the maximum lateness. For this problem n/2/F/Lmax' we first give a solvable case in the sense that the optimal schedule can be easily found. Then we again propose an approximation algorithm for general n/2/F/Lmax and derive its worst case bound.
TL;DR: An interactive computerized scheduling system has been tailored using a commercial MPS and its Extended Control Language and the man-hours required for making a final schedule has been reduced to one-third as compared with the previous way.
Abstract: This paper presents an implementation of a decomposition-coordination approach to petroleum refinery production scheduling. In this approach the scheduling problem is not formulated as a single mathematical programming model to be solved through a computerized system, but it is dealt with as a mathematical programming process, in which a number of small problems are practically solved, and their solutions are combined into an overall schedule Our approach does not pursue an exact optimum, but quite satisfactory schedules have been generated from a practical viewpoint and productivity in the scheduling process has been remarkably raised An interactive computerized scheduling system has been tailored using a commercial MPS and its Extended Control Language (ECL). The man-hours required for making a final schedule has been reduced to one-third as compared with the previous way
TL;DR: In this paper, the authors describe the development of an on-line, real-time, scheduling method for a computer aided manufacturing system and relates one application example in LSI wafer fabrication factory.
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TL;DR: The purpose of this paper is to present an analysis of dispatching rules using a job shop simulation model, which involves 20 different dispatches rules in a 9-machine shop, for 4 sets of 10000 jobs.
Abstract: Production scheduling is concerned with the allocation of resources and the sequencing of tasks. Sequencing problems, except for special cases, are very difficult to solve analytically. Consequently, heuristics are used frequently to solve this problem. A popular class of heuristics is referred to as dispatching rules. A dispatching rule is a discipline by which jobs are assigned priorities at different work stations. Competing rules in a multi-stage, multi-job problem are generally evaluated on the basis of their performance in simulation tests. The purpose of this paper is to present an analysis of dispatching rules using a job shop simulation model. The analysis involves 20 different dispatching rules in a 9-machine shop, for 4 sets of 10000 jobs.
TL;DR: A flexible scheduling system developed by a surgical intensive care unit nursing staff around a core of 12%-hour work shifts and a master schedule, stafling guidelines, and a work agreement were prepared.
Abstract: Flexible scheduling and its impact on nursing are topics of growing interest among nurses. Described in this article is a flexible scheduling system developed by a surgical intensive care unit nursing staff around a core of 12 1/2-hour work shifts. As a result of careful consideration and planning, a master schedule, staffing guidelines, and a work agreement were prepared for a large department of nursing. Administrators of other departments of nursing implementing flexible scheduling should find this information useful.