• 산업경영시스템학회지
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• 제18권36호
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• pp.219-232
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• 1995

Even though Just-In-Time Production System is introduced to industry in order to strengthen competition, applying this production system to field is hard and some problems are occurred. On this study, the algorithm which become smoothed production, one of the prerequisite condition for implementing Just-In-Time, are developed. On the other word. it is possible to become smoothed production based on keeping Lot Production System. The possibility of establishing more stable smoothed production scheduling are proved on this study by comparing with previous researches.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권2호
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• pp.116-121
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• 2006

This paper presents an effective modeling and simulation scheme of solar-powered hydrogen production system (PV-SPE: Photovoltaic Solid Polymer Electrolyte). Existing Hydrogen production technologies can produce vast amounts of hydrogen from hydrocarbons but emit large amounts of carbon dioxide (CO2) into the atmosphere. Advanced hydrogen production methods need development. Renewable technologies such as solar and wind need further development for hydrogen production to be more cost-competitive from other resources. In this paper, authors have focused on a renewable technology to move one step further toward commercial readiness of solar-powered hydrogen production system. Software (PSCAD/EMTDC) based model of PV-SPE system is studied for an effective simulation of hydrogen production system. Using the simulation results, an actual PV-SPE system is implemented to verify the simulation results by comparing them with actual values obtained from the data acquisition system.

• 대한안전경영과학회지
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• 제3권1호
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• pp.93-105
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• 2001

Many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources have been proposed, and GT, MRP and JIT are frequently used among these systems. The three systems have merits and demerits through comparing with each other. Because each system has mutual dependence, a hybrid production system Is necessary for using their merits maximally. In this study, a hybrid production system is designed by combining GT, MRP and JIT, which is suitable in the domestic production system and it is presented as followings. -. Basic research works for G7, MRP and JIT. -. Comparison and analysis are carried out for each system.- . The hybrid production system is designed. -. The hybrid production system is developed.

• The International Journal of Costume Culture
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• 제3권3호
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• pp.235-245
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• 2000

The purposes of this study were 1) to investigate usage level of production strategies based on group of production environment, 2) to investigate usage level of production systems based on group of production strategy, and 3) to analyze each of company performance based on group of production strategy and system. For this study, the questionnaires were administered to 215 apparel manufactures in metropolitan area from Feb. to Mar. 1998. Employing a sample of 201, data were analyzed by factor analysis, descriptive statistics, cluster analysis, discriminant analysis, and multivariate analysis of variance. The following are the results of this study. 1. Concerning production strategy due to group of production environment, the stable group and the complicated group prefer to rice/quality centered strategy but the level of usage for strategies is so pretty that it is not significant to carry out them. 2. Concerning production system due to group of production strategy, the workers centered group is occupied high in the price/quality centered group & the complex group. And also the product centered system is occupied high in the flexibility centered group. 3. Concerning company performance due to group of production strategy and system, the price/quality centered group holds low position of performance comparing to another groups. And the performance of the managers centered group is higher than that of the workers.

• 대한안전경영과학회지
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• 제5권4호
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• pp.209-217
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• 2003

The traditional Kanban needs a lot of preconditions for fitting conditions of dynamic production processing environment. The traditional Kanban isn't suitable conditions of dynamic production processing environment. Therefore conditions of dynamic production processing environment is needed more stable system. This study is describe CONWIP system such as suitable in dynamic production processing environment. Most Pull system is a Kanban system than use Kanban cards or signal for production management and inventory control. The object of Kanban system is reducing inventory between shop-floor that can reduce inventiry cost. If the system reduce the number of Kanban cards would be reduce the working process WIP, can be reduced and can be found all potential problem of production between shop-floors. This study apply to CONWIP system model for Korean industrial companies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1579-1602
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• 2020

In the design of production system, buffer capacity allocation is a major step. Through polymorphism analysis of production capacity and production capability, this paper investigates a buffer allocation optimization problem aiming at the multi-stage production line including unreliable machines, which is concerned with maximizing the system theoretical production rate and minimizing the system state entropy for a certain amount of buffers simultaneously. Stochastic process analysis is employed to establish Markov models for repairable modular machines. Considering the complex structure, an improved vector UGF (Universal Generating Function) technique and composition operators are introduced to construct the system model. Then the measures to assess the system's multi-state reliability and structural complexity are given. Based on system theoretical production rate and system state entropy, mathematical model for buffer capacity optimization is built and optimized by a specific genetic algorithm. The feasibility and effectiveness of the proposed method is verified by an application of an engine head production line.

• 산업공학
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• 제21권4호
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• pp.418-434
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• 2008

This paper studied issues in decision making on the production control policy of a cathode plate manufacturing process in zinc refining plant. The present production system has a long lead time from raw materials (aluminum plate) to products (cathode plate) due to many WIP inventories. Because WIP inventories are stocked at each process and moved from one place to another frequently, they are the main cause of inefficiency in the process. In this paper, to solve this problem, several production control policies have been identified and studied. Several simulation models are used to compare the performances of these production control policies. The output lead time and WIP (Work In Process) of real production system are compared with those of simulation models. PUSH, CONWIP, DBR, KANBAN and CONWIP-DBR models have been used to simulate and review the optimized production control policy that achieves the target output quantities with decreased lead time and WIP. The simulation results of each production control policy show that CONWIP and CONWIP-DBR models are the good production control policy under the present production system. Especially in present production system, CONWIP with one parameter is easier control policy than CONWIP-DBR with two parameters. Therefore CONWIP has been selected as the best optimum production control policy. With CONWIP, lead time has been reduced by 97% (from 6,653 to 187 minute) and WIP has been reduced from 1,488 to 53, compared to the present system.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2011년도 추계학술대회
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• pp.162-163
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• 2011

This paper presents the system dynamics methodology for modeling and control the production/inventory system. Under system dynamics point of view, we can apply some production/inventory policies as if we use the control laws for dynamics systems, then the behavior of system is analyzed and evaluated to improve the performance of production/inventory system. We also utilize the hybrid modeling method for the dynamic of production system with the combination of Matlab/Simulink and Matlab/Sateflow. Finally, the numerical simulation results are carried out in Matlab/Simulink environment and compare with the results from other works. It is shown that our approach can obtain some good performances (such as operational cost, stability of inventory, customer service level).

• 산업경영시스템학회지
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• 제25권4호
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• pp.69-78
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• 2002

The basic purpose of the JIT(Just In Time) production system is to increase profits by reducing costs-that is, by completely eliminating waste such as excessive stocks or workforce. To achieve cost reduction, Production must promptly and flexibly adapt to changes in market demand without having wasteful slacks. :iuch an ideal is accomplished by the concept of JIT, producing the necessary items in the necessary quantities at the necessary time. The JIT production system is supported by the following: reduction of setup time, smoothing of production, standardization of jobs, improvement activities, design of machine layout, Kanban system, autonomation etc. This study examined the present state of the domestic JIT production system and introduced the empirical case of JIT application a small and medium manufacturing company. A synthetic resins manufacturing company applied JIT principles to its processes and achieved the great performance.

• 대한안전경영과학회지
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• 제6권3호
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• pp.187-196
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• 2004

By successful establishment of Supply Chain Management System they should make the supply chains speedy and combine production information system with the outcome system and thus they reinforce the competition of the production system of local enterprises in accordance with the rapid decision making. Supply chain coordination improves if all supplier of chain take actions that together increase total supply chain profits. To design of Modularity by the grouping supplier, the proposed method is to develop the most appropriate production system models through the reflection of JIT system in the Supply Chain Management which is necessity of the times and its importance. The objects of this study is to develop the most appropriate production system Model and optimal profit model in the process line and to provide the enterprises with the models which are based on the Supply Chain Management.