• Journal of computational fluids engineering
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• v.20 no.3
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• pp.8-14
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• 2015

More and more, spaces are decreasing which satisfy multiple requirements for wind power plants. However, areas which have excellent wind resources and are free to civil complaints occupy a large space, although they are exposed to the cryogenic environment. This study conducted a thermal-fluid analysis of a cryogenic chamber for testing large wind turbine parts exposed to the cryogenic environment. The position of supply air is placed to the upper area to compare each cooling performance for each location of various outlets in mixing ventilated conditions. The study carried out CFD analysis for the chamber both with and without a test object. For the cases without the test object, the air temperature of the upper supply and down extract type chamber was cooled faster by 5-100% than the others. However, for the cases with the test object, the object temperature of upper supply and center extract on the opposite side type chamber was cooled faster by 33-132% than the others. The cooling performance by the air inside the chamber and the test object did not show the same pattern, which implicates the need to consider the cooling performance by not only the air but also the test object in the large cryogenic chamber design for testing large parts.

• Journal of Korean Society for Quality Management
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• v.28 no.4
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• pp.204-222
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• 2000

Supply Chain Management is a process-oriented concept, integrated approach to procuring, producing, and delivering products and services to customers. Supply Chain Management covers the management of material, information, and funds flows. A strategic supply chain management produces for value maker and the ultimate customer. One aim of this paper is to determine the effect of contract parameters on the quality of the end product of the supplier-producer chain. The supply chain management is viewed as a single entity rather fragmented. This research constructed model the relationship of supply chain management to quality management. The questionnaire were tested with survey of supplier's employee and the result were analyzed using SEM(Structural Equation Model). As a result, Quality performance positively depends on the communication, coordination, and process management between the supplier and the producer.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.331-333
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• 1999

Power supply for Nuclear Power Plant was developed, and MMI monitoring circuit was added to the main function of power supply. The developed power supply is designed to show equal or higher performance compared with the existing power supplies. Performance of the power supply is verified by simulations, experiments, and authentication test for Q-class, he status of power supply and fault waveform can be displayed and analyzed on PC by RS-232C port. By adopting the latest parts, mainly domestic models, production cost and delivery can be reduced. Replacement period of capacitor can be extended by life estimation.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.1
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• pp.25-36
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• 2006

Consider a supply chain in which a vendor supplies a product to a buyer. We assume that the buyer's and vendor's inventory cost structures are different, resulting in differences in inventory order/delivery cycle times. Here, if one party insists on its individually optimal order/delivery quantity, the other party will suffer from mismatches in cycle times. Under this scenario, coordination contracts that make use of either a Net Term/Two parts Term Trade Credit or a Quantity Discount are designed to align individually optimal order Quantities. We compare and analyze the perform ances of these contracts. The focus of the comparison is the ability of contracts to generate a lower cost for the supply chain. We show that a Trade Credit policy can be effectively used to coordinate a supply chain. In many cases it will result in a lower supply chain cost compared to that achieved by using a Quantitative Discount policy.

• Industrial Engineering and Management Systems
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• v.13 no.1
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• pp.52-66
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• 2014

Promotion of a closed-loop supply chain requires disassembly systems that recycle end-of-life (EOL) assembled products. To operate the recycling disassembly system, parts selection is environmentally and economically carried out with non-destructive or destructive disassembly, and the recycling rate of the whole EOL product is determined. As the number of disassembled parts increases, the recycling rate basically increases. However, the labor cost also increases and brings lower profit, which is the difference between the recovered material prices and the disassembly costs. On the other hand, since the precedence relationships among disassembly tasks of the product also change with the parts selections, it is also required to optimize allocation of the tasks in designing a disassembly line. In addition, because information is required for such a design, the recycling rate, profit of each part and disassembly task times take precedence among the disassembly tasks. However, it is difficult to obtain that information in advance before collecting the actual EOL product. This study proposes and analyzes an optimal disassembly system design using integer programming with the environmental and economic parts selection (Igarashi et al., 2013), which harmonizes the recycling rate and profit using recyclability evaluation method (REM) developed by Hitachi, Ltd. The first stage involves optimization of environmental and economic parts selection with integer programming with ${\varepsilon}$ constraint, and the second stage involves optimization of the line balancing with integer programming in terms of minimizing the number of stations. The first and second stages are generally and mathematically formulized, and the relationships between them are analyzed in the cases of cell phones, computers and cleaners.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.203-212
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• 2007

Until now, used parts of automobiles necessary for the remake of automobiles have been recovered from auto repair shops. But it takes much time and cost to collect those parts because the recovery system has not been set up. Furthermore. used parts from auto junk yards have rarely been used for the remaking. This current situation will improve by adopting DISRMPA(Distribution Information System for Recovery and Management of used Parts of Automobiles) designed by the author. Auto repair shops or junk yards input the information of used parts to make a database in the system. Remaking companies use the database to find and recover used parts. The DISRMPA can help prepare stabilized ways to supply used parts.

• Journal of Distribution Science
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• v.15 no.8
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• pp.15-28
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• 2017

Purpose - Many researchers analyze VMI as a supply chain collaboration program to reveal its true value. Most of them focus on the dyadic relationship in two stage supply chain systems. This study examines the effect of VMI when it is applied to the different parts of three stage supply chain systems. Research design, data, and methodology - Based on three stage supply chain, this study compares three different systems including full VMI, partial VMI, and non-VMI by using mathematical models. The performances of three systems are compared with the numerical examples of the proposed supply chain models. Results - The numerical examples reveal that full VMI where the manufacturer controls inventories at all stages outperforms any other systems in terms of the system profit and enables all individual members to gain greater profits than non-VMI. Meanwhile, under partial VMI where VMI is implemented between the wholesaler and retailer, only these two members improve their performances and the manufacturer who does not belong to VMI makes less profit than even under non-VMI. This study also examines the impact of market size and profit margin on the system performance. Conclusions - The result of this study supports the common belief that VMI secures the best result when it is applied to the entire supply chain system. The additional findings from the numerical analysis are discussed.

• Journal of Information Technology Services
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• v.8 no.4
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• pp.115-128
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• 2009

In today's changing environment where the product life-cycle is becoming shorter, enterprises are forced to introduce new products as rapidly as possible and to score a success in a market. It is important to manage suppliers who supply parts of the new products to satisfy variable demands. We suggest performance measures of flexibility for suppliers in new products environments. We analyzed the measures from literatures, SCOR (Supply Chain Operations Reference) model and several scorecards. A simulation study was made with the measures in order to understand adaptability of a supply chain. It could help a manufacturer make a decision of purchasing and find a bottleneck supplier.

• Journal of Korean Society for Quality Management
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• v.38 no.2
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• pp.180-189
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• 2010

For the success of total six sigma innovation, it is necessary to improve the suppliers' quality in the supply chain. This paper presents the deployment and support system of six sigma innovation for supply chain quality improvement, with the application to an aerospace production company. The process of project selection, project implementation, financial effect verification, benefit sharing is presented. This paper will benefit the companies which are going to enhance all the companies in the supply chain via six sigma activities.

• Electronics and Telecommunications Trends
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• v.36 no.3
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• pp.1-11
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• 2021

In this study, we analyze the automotive chip ecosystem that recently caused the global supply shortage, and attempt to derive policy implications for us from the conclusion. Automotive chips are critical parts that control various systems so that a vehicle can drive itself or operate with electricity. The current shortage in supply and demand for automotive chips is due to the inconsistency between supply and demand between automotive chip companies and car manufacturers. To promote the automotive chip industry, new investment incentives, tax cuts, and human resource training are needed.