• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.79-84
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• 2010

액체로켓엔진 공급시스템을 구성하는 배관, 오리피스, 굽힘관, 벨로우즈, 밸브, 플랜지 등의 공급계 부품들에 대한 액체로켓엔진 공급시스템 모듈을 개발하였다. 이 모듈은 각 부품별로 Sizing이 가능하며 압력강하를 계산할 수 있다. 또한, 공급시스템이 구성되면 시스템 전체 부품 개수, 압력강하, 출구압력, 무게를 도출할 수 있다.

• 대한안전경영과학회지
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• 제8권3호
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• pp.115-123
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• 2006

The main focus of this study is to investigate the performance of a clark-scarf type multi-echelon serial supply chain operating with a base-stock policy and to optimize the inventory levels in the supply chains so as to minimize the systemwide total inventory cost, comprising holding and backorder costs as all the nodes in the supply chain. The source of supply of raw materials to the most upstream node, namely supplier, is assumed to have an infinite raw material availability. Retailer faces random customer demand, which is assumed to be stationary and normally distributed. If the demand exceeds on-hand inventory, the excess demand is backlogged. Using the echelon stock and demand quantile concepts and an efficient simulation technique, we derive near optimal inventory policy. Additionally we discuss the derived results through the extensive experiments for different supply chain settings.

• Journal of Information Technology Applications and Management
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• 제13권2호
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• pp.41-54
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• 2006

In this paper, we investigate the inter-organizational information systems effect to supply chain partnerships, and subsequently to the performance. The conceptual model for the causal relationships among interorganizational systems usage, interaction, partnership, and supply chain performances has been developed. Theoretical framework is based on the partnership research in relationship marketing area, and the interaction model from IMP group. The questionnaires are designed to test the hypotheses of the conceptual model. The survey result supports our hypotheses that collaborative IT effects to increase the interaction between the firms, and interaction causes to enhance the partnership quality. Also, the level of partnership shows strong positive correlation with the supply chain performances. Despite the limitations of collected sample data size, our study reveals the fact that inter-organizational information systems contribute to supply chain performance through enhancing the interaction and partnership level between the supply chain partners. Our research result is distinct from the most extant literatures that investigated the firm's collaboration impact on interorganizational systems usage.

• 산업공학
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• 제19권1호
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• pp.53-61
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• 2006

We propose a new supply chain planning methodology for both a manufacturer and a distributor in order to find a global supply chain plan for functional product markets. Functional products as opposed to innovative products include the staples that people buy regularly from their nearby places to satisfy basic needs. In the functional product market, the distributor has an initiative of supply chain control and planning with a freedom to request any profit maximizing order quantities until the manufacturer refuses, whereas the manufacturer may not provide more than requested. In this paper, two independent agents on behalf of the manufacturer and the distributor are introduced, and supply chain planning can be conducted by collaboration between them. In addition, mathematical models and a numerical example are presented to show the possibility of the proposed methodology.

• Industrial Engineering and Management Systems
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• 제12권2호
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• pp.103-111
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• 2013

This paper discusses how to manage supply chain disruption risks from natural disasters or other low-likelihood-high-impact risk drivers. After the catastrophic earthquake in Eastern Japan and the severe flood in Thailand, most companies have been attempting to re-establish the business continuity plan to prevent their supply chain from disruption. However, the challenges for managers and individual risks are often interrelated, and thus, actions that mitigate one risk can end up being no contribution as a whole. In this paper, we describe a framework for assessing how much impact individual mitigation strategies have on the entire supply chain protection against disruption, using network reliability. We propose three categories of risk-mitigation approaches: Stabilization, Absorption, and Duplication. We analyze the situation under which each of these strategies is the best suitable. With a clear understanding of relations between these mitigation strategies and the entire supply chain risks, managers can select effective risk-reduction approaches to their supply chain.

• 상하수도학회지
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• 제19권3호
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• pp.363-369
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• 2005

This paper presents the integrated technique of water quality analysis and Geographic Information System(GIS) for assessing the variation of free chlorine residuals by water temperature and supply distance in Sangri water supply system in Daegu. GIS was utilized for mapping projectmap, extraction of a pipeline route, and supply distance. Free chlorine residual is analyzed every month for appraising the seasonal variation. As a result, free chlorine residuals are affected both water temperature and water supply distance, and it becomes worse as water temperature and water supply distance is increased. To maintain 0.4mg/l of free chlorine residual, initial dose concentration should be over 1.85mg/l in summer.

• 설비공학논문집
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• 제21권4호
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• pp.209-214
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• 2009

The purpose of this study is to investigate the effect exchanging water supply on the' rainwater in detached house. It is difficult to decide water supply amount for a closet in detached house, Therefore, to obtain water supply for closet in detached house, it used regression equation using 1,569 data of frequency of used closet and during 120 days. In detached house, the frequency of used closet is 14.6 times/day and water supply amount is $219 {\ell}/day$. The optimum rainwater tank size which is decided by regression equation and using weather data is $8.5\;m^3$. The effect exchanging water supply on the rainwater in detached house is up 50%.

• 대한안전경영과학회지
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• 제14권4호
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• pp.71-77
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• 2012

It is very important the collaboration and risk management of supply chain between the parent company and its partners in the supply chain risk management(SCRM). It was known that the SCRM approach is very different between a large enterprise and a small and medium-sized enterprise. This paper deals with the suggestion about SCRM structure for a small and medium-sized enterprise. This SCRM structure consist of risk identification, risk assessment, and risk mitigation. We expect that this SCRM structure promote the collaboration between a parent company and its partners to alleviate the supply chain risk.

• 전자통신동향분석
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• 제38권4호
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• pp.81-94
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• 2023

The increased adoption of open source security management in supply chains is gaining worldwide attention. In particular, as security and threatening situations, such as solar winds, Kaseya ransomware, and Log4j vulnerability, are becoming more common in supply chains using software (SW)-defined networks, SW bills of materials (SBOMs) for SW products should be prepared to protect major countries like the United States. An SBOM provides SW component information and is expected to become required for SW supply chain management. We focus on SW supply chain management policies and SBOM trends in major countries and private organizations worldwide for safe SW use and determine the current status of Korea and ETRI's open source SW supply chain management trends.

• 한국정보기술학회 영문논문지
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• 제9권2호
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• pp.75-87
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• 2019

This paper presents a fully digital controlled power supply unit for the wireless controlled dimmable LED lighting system. The proposed power supply designed using a fly-back converter, which is directly controlled by a microprocessor. Although the proposed circuit does not sense the AC input current and has not AC input voltage feed-forward, it can achieve a high power factor. The proposed power supply directly regulates the output power for LED loads using the PWM and PFM control of the fly-back converter without additional regulator. For a wireless remote control function, the Zigbee modem is equipped in the proposed power supply. A prototype set-up has been built and tested. Through the experiment with a prototype set-up, the usefulness of the proposed power supply is verified.