• Korean Management Science Review
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• v.11 no.1
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• pp.23-37
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• 1994

This paper discusses the methodology for the operational performance of unit-load automated guided vehicles(AGVs) in a flow-shop-type flexible machining and assembly systems (FM/AS). Throughout the paper, AGVs are working as a carrier and mobile workstation. For a double-loop FM/AS, in which one loop is dedicated to machining and the other to assembly, three AGV operating strategies are proposed. Considering the entering interval and travel time of AGVs between workcenters, the strategies are developed to determine the best job sequence which minimizes the makespan and vehicle idle time. Entering times of AGVs and the required minimum number of AGVs are obtained on the basis of the best job sequence. When the number of AGVs are limited, entering times of AGVs are adjusted to maximize the utilization of AGVs.

• Journal of Korean Institute of Industrial Engineers
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• v.13 no.2
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• pp.35-46
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• 1987

To minimize makespan for preemptive sequence dependent job scheduling with parallel identical processors, fundamental results, as the basis of new algorithm to be presented, such as McNauton's algorithm for independent jobs, Hu's characterization for dependent jobs, and Muntz-Coffman's algorithm, were first introduced. Then a huristic procedure was presented applying those concepts of zoning of assembly line balancing and of resource leveling on CPM network scheduling with two or more of parallel machines in general. New procedure has eliminated presumative machine assignment using ${\rho}$, rate of resource capability (${\rho}$ < 1), for practical scheduling.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.4
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• pp.218-225
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• 2009

This paper considers a parallel-machine scheduling problem with job release times and sequence-dependent setup times. The objective of this problem is to determine the allocation policy of jobs and the scheduling policy of machines so as to minimize the weighted sum of setup times, delay times, and tardy times. A mathematical model for optimal solution is derived and a meta heuristic algorithm based on the improved ant colony system is proposed in this paper. The performance of the meta heuristic algorithm is evaluated through compare with optimal solutions using randomly generated several examples.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.123-131
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• 2009

The purpose of this study was to define the job description for food safety specialist, and to describe the duties and tasks of the job based on the detailed analysis of specific food safety work performed by dietitians. The job analysis was 8 professional panels and a Developing A Curriculum(DACUM) facilitator. The research was done in order to fully define the task element, process, and sequence of a food specialist and was completed by DACUM analysis. The job definition of food safety specialist is one who manages food safety through analysis, safety evaluation, inspection, and hazard blocking in all processes related to the purchase, distribution, storage, manufacture, and marketing of foods and food materials. The job description on the DACUM research chart for food safety specialist contained 7 duties and 79 tasks. Its duties were defined as the specific and independent work of a food safety specialist, and were composed of 7 duties, i.e. hazard analysis of foods and related affairs, safety evaluation of purchased food materials, safety management of food/food materials distribution/storage, safety management of food manufacture, safety examination of food marketing, administration affairs on food safety, and self-development. For the future, this study suggests a curriculum, that shall be basis of program planning and food safety operation for subjects within many schools.

• Journal of the Korea Society for Simulation
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• v.31 no.2
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• pp.1-10
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• 2022

The packaging plastic manufacturing(blown film) industry has long developed in China, but most of them are small/medium-sized enterprises, and it is very rare to have appropriate operation plans suitable for their own business. The packaging plastic manufacturing industry(blown film) follows a typical Make-To-Order method, and the sequence of processing orders is very important. Waste of materials incurred by frequent conversions of production cannot be avoided, and generally, related costs incurred during conversion production are also different. Therefore, this study developed a job sequence determination model for improving operating profits using @RISK simulation software, compared and analyzed 3 actionable clustering treatment methods proposed by technical managers and field experts under the actual situation of the factory.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.11a
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• pp.85-88
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• 2003

In case that any jobs in a Job Shop can be scheduled on more than one machine and may have flexible operation sequences, with considering such case it is very difficult and complex to make the optimal process plans and scheduling. But they should be considered for an integrated model to perform more effective process planning and scheduling in this job shop problem. In this paper, we propose GA-based scheduling method to integrate effectively the problem of alternative machines, alternative operation sequences and scheduling. The performance of proposed GA is evaluated through comparing integrated scheduling with not integrated scheduling in molding company with alternative machines and operation sequences. Also, we use benchmark problems to evaluate performance. The scheduling method in this research will apply usefully to real world scheduling problems.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.151-156
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• 2001

Performance-based course design on the job of receiving substation installations is presented to achieve a work based curriculum development. It includes a job analysis method called ISD(Instructional Systems Design & Development) and DACUM(Developing a Curriculum) which is designed to accept various requirements of industrial fields. It is provided with course profile, key contents, terminal learning objectives, intermediate learning objectives, instruction strategy, instruction sequence, case study, action learning and lesson plan.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.209-213
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• 1998

This study considers flowshop scheduling problem related to flexible maufacturing cell in which consists of two machining centers, robots for loading/unloading, and an automated guided vehicle(AGV) for material handling between two machining centers. Because no machinng center has buffer storage for work in process, a machining center can not release a finished job until the empty AGV is available at that machining center. While the AGV cannot tranfer an unfinished job to a machining center until the machining center empty. In this paper, an new heuristic algorithm is given to find the sequence that minimize their makespan.

• Proceedings of the Safety Management and Science Conference
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• 2003.05a
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• pp.285-290
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• 2003

There is only one server available and arriving work require services from this server. Job are processed by the machine one at a time. The most common objective is to sequence jobs on the severs so as to minimize the penalty for being late, commonly called tardiness penalty Based on other objectives, many criteria may serve as s basis for developing job schedules. Therefore, this study tries to proposed that Scheduling by customer needs group for minimizing the problem and reducing inventory, product development time, cycle time, and order lead time.

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.4
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• pp.607-617
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• 1996

This paper shows that fuzzy set theory can be useful in modeling and solving job scheduling problems with uncertain processing times. The processing times are considered as fuzzy numbers(fuzzy intervals or time intervals) and the fuzzy Delphi method is used to estimate a reliable time interval of each processing time. Based on these time estimates, we then propose an efficient methodology for calculating the optimal sequence and the fuzzy makespan.