• 대한산업공학회지
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• 제34권3호
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• pp.296-307
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• 2008

A semiconductor production system has sophisticated manufacturing operations and needs high capital investment for its expensive equipment, which warrants efficient real-time flow control for wafers. In the bay, we consider material handling equipment that can handle multiple carriers of wafers. The dispatching logic first determines the transportation time of each carrier to its destination by each unit of transportation equipment and uses this information to determine the destination machine and target carrier. When there is no available buffer space at the machine tool, the logic allows carriers to stay at the buffer of a machine tool and determine the delay time, which is used to determine the destination of carriers in URL. A simulation study shows this dispatching logic performs better than the procedure currently in use to reduce the mean flow time and average WIP of wafers and increase efficiency of material handling equipment.

• 산업공학
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• 제14권4호
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• pp.356-364
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• 2001

Production Improvement Method in TOC consists of five steps, but it is very difficult for most firms to implement it because it lacks the detailed methods at each step. This paper suggests some of detailed methods to implement the TOC. In the first step, computer simulation is used to identify the constraints in production lines. Subsequently, ASP, AUT, and CM calculation are defined for the second step, which are helpful to exploit the company's constraints. We also suggest the OEE method to effectively exploit the constraints of production lines in the factory. Finally the TOC/OEE procedure is suggested to optimize the investment in the fourth step. As an illustrative example, we introduce a case of a wafer manufacturer to adopt the suggested methods. The benefits of implementating the suggested methods are addressed in the framework of the balanced scorecard.

• 한국경영과학회지
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• 제21권2호
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• pp.17-33
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• 1996

Automatic transfer defined as an integrated system with a number of workstations, interstation storage buffers, automatic device and a control system, play a major role in ass production systems. Due to high capital investment needed for an automatic transferline, greater care should be taken in its design so as to maximize the system performance. One may to control the system performance is to control buffer storage. To control the interstation work-in-process inventory, we propose dual limit switches which control the buffer storage with two parameters, R and r. Under the policy, proceding station is forced down when the inventory level in the buffer reaches R until the level falls to r. For the model developed, we analyze the system characteristics and find the optimal control parameters with a serach procedure.

• 가정과삶의질연구
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• 제14권3호
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• pp.109-120
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• 1996

While theories of portfolio selection have been developed very little is known about how individuals actually go about constructing their asset potfolios. This study investigates empirically the characteristics of household's assets and which factor associated with risky and safe asset amount. Data used in this study consisted of 2,164 households and the statistics employed to analyze the data are univariate procedure Logit analysis and OLS. The results of this study were as follows: Among 2,164 households 505 housholds(23.3%) had risky assets. Average risky asset amount is 8,351,500 won and average safe asset amount is 7,086,900 won. Region education and occupation of household head home ownership transfer and other income and total expenditure had significant effects on either and other income and total expenditure had significant effects on either household having risky asset or safe asset. Financial income transfer and other income and total expenditure had significantly p sitive relation with the risky asset amount. Whereas age and the occupation of household head the sense of economic wellbeing earned financial tranfer and other income and total expenditure had significantly positive relation with safe asset amount.

• Journal of Magnetics
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• 제16권4호
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• pp.379-385
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• 2011

This paper presents an optimal design of a direct-drive permanent magnet synchronous generator for a small-scale wind energy conversion system. An analytical model of a small-scale grid-connected wind energy conversion system is presented, and the effects of generator design parameters on the payback period of the system are investigated. An optimization procedure based on genetic algorithm method is then employed to optimize four design parameters of the generator for use in a region with relatively low wind-speed. The aim of optimization is minimizing the payback period of the initial investment on wind energy conversion systems for residential applications. This makes the use of these systems more economical and appealing. Finite element method is employed to evaluate the performance of the optimized generator. The results obtained from finite element analysis are close to those achieved by analytical model.

• 한국항해항만학회지
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• 제28권1호
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• pp.59-67
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• 2004

세계 경제의 글로벌화에 따른 국제물류의 환경변화로 세계 주요 항만은 각 권역에서의 물류거점 항만이 되기 위한 경쟁이 치열하게 전개되고 있다. 우리나라(한국)에서도 동북아지역에서의 지리적인 이점을 활용하여 새정부의 출범과 함께 국가차원에서 한반도를 동북아 물류 중심기지로 육성하기 위한 전략을 적극적으로 추진 중에 있다. 그 중 한가지 전략이 관세자유지역 지정을 통한 다국적 물류기업의 유치로 물류산업의 활성화 및 동북아의 국제물류기지로 육성할 계획이다. 그러나 세계 각국에 비해 후발주자인 부산항 관세자유지역에 세계적인 다국적 기업의 유치를 위해서는 중앙정부 및 지방정부의 많은 투자가 필요한 것이 현실이다. 따라서 본 연구에서는 중국 및 일본에 있는 업체의 설문 조사를 토대로 부산항 관세자유지역의 경쟁력을 분석하고 활성화 방안을 제시하는데 목적을 두고 있다. 컨조인트 분석을 통한 응답 업체의 선호도 조사결과 투자절차 및 제한이 36.2％로 가장 높은 선호도를 나타내고 있기 때문에, 관세자유지역에 기업을 유치하기 위해서 가장 중요시해야 할 전략은 투자절차 및 제한에 대한 문제점을 해결해야 한다. 시장점유율 시뮬레이션 분석을 통하여 경쟁력을 평가한 결과, 5개 국가중 UAE의 경쟁력이 가장 높고 한국은 가장 낮은 것으로 나타났다. 그러나 투자절차 및 제한과 생산요소 비용의 현재 수준을 개선시켰을 경우에는 5개 국가중 UAE 다음으로 경쟁력이 높은 것으로 나타났다. 따라서 부산항 관세자유지역이 경쟁력을 가지기 위해서는 투자절차 및 제한에 대한 개선뿐만 아니라 생산요소 비용에서도 기업들이 만족하는 수준으로 절감되어야 한다는 것을 알 수 있었다.

• 한국중재학회지:중재연구
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• 제27권2호
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• pp.3-18
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• 2017

International legal reviews on ISD, a procedure for resolving disputes under the Korea-US FTA, are examined from the perspective of law. If the ISD system does not exist, even if the investor suffers damage due to the illegal act of the host country, he or she must file a lawsuit through the court of the host country, which is unreasonable from the investor's point of view and makes it difficult to guarantee fairness and transparency. Some of the Koreans pointed out that there are some problems with the KORUS FTA dispute settlement regulations, and that the United States federal courts are taking a friendly attitude to the decisions made by the US Customs in determining the dispute by the KORUS FTA Agreement and the US Customs Act. In cases where the State does not violate international law but results in harmful consequences, the responsibility of one country is borne by the treaty. Foreign investment always comes with many challenges and risks. Therefore, the ISD system is a fair and universal arbitration system, which is considered to be a necessary system even for protecting the Korean companies investing abroad. In the investment treaty, compensation for the nationalization of foreign property and reimbursement under the laws of the host country were dissatisfied with foreign investors. In particular, some Koreans have pointed out that there are some problems in the KORUS FTA dispute resolution regulations and there is a need for further discussion and research. Based on the experiences and wisdoms gained in the course of Korea-US FTA negotiations, the dispute arbitration mechanism is urgently needed to reduce the possibility of disputes and to make amicable directions.

• Korean Chemical Engineering Research
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• 제58권4호
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• pp.550-564
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• 2020

증류탑은 경제적 효율성, 높은 신뢰성 및 자료 확보의 용이성으로 석유화학 공정 설계 시 화학 성분의 분리를 위해 적용되는 주된 기술 중 하나이다. 하지만, 기본적으로 에너지 소비 및 투자비가 높은 설비이기 때문에, 운전비와 투자비에 대한 Trade-Off 분석을 진행하여 가장 경제적인 증류탑 설계 진행이 필요하다. 본 연구에서는 가능한 많은 공정 엔지니어의 활용을 위해 대중적 공정 모사 프로그램인 Aspen Plus를 사용하여 검토를 진행하였다. 증류탑 최적화 진행시의 설계 변수를 정의하여 공정 엔지니어의 주관적인 판단에 의한 설계 품질의 편차를 최소화 하였으며, 불필요한 검토 과정 배제 및 체계적/효율적인 절차를 수립하여 설계에 소요되는 시간 및 인력 소요를 최소화 하였다. 또한, 증류탑 단수 최적화 검토시 투자비의 신뢰성 있는 산출을 위해 APEA (Aspen Process Economic Analyzers) 프로그램을 도입하고, APEA 사용에 대한 효율적인 방법에 대해서도 다방면으로 검토하여 최적화 절차를 수립하였다.

• 한국병원경영학회지
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• 제18권1호
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• pp.18-41
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• 2013

This study was aimed to identify the current status of medical service quality of medical institutes; propose improvements; and find out the impact of medical service quality by its attribute on overall customer satisfaction. The research was conducted on the out-patients and in-patients in a high-level general hospital located in A city. To examine the research, the IPA was utilized to identify the priority requirements for improving the medical service quality. The study also applied an extended theory to the analysis on mismatch between the level of satisfaction and importance recognized by the clients, to examine the impact of the above mentioned factors on the overall satisfaction and intention to revisit and recommend the hospital. For out-patients, the result showed that "hospital hygiene" had a positive and negative impact on the clients' intention to revisit the hospital in priority improvements. In terms of the sustainable improvements, "doctor's skill" had a negative impact on the overall service satisfaction, whereas "state-of-the-art facility" and "nurse's instruction" had a positive impact on the intention to revisit the hospital. In long-term improvements,"complaint remedy" had a positive impact on the intention to recommend the hospital but there were no relevant factors in excessive investment. On the other hand, for in-patients, the result demonstrated that there were no relevant factors in priority improvements and sustainable improvements. The factor of"service procedure speed"had a positive as well as negative impact on the intention to revisit the hospital. In excessive investment,"nurse's empathy"had a positive impact on the intention to recommend the hospital.

• 한국게임학회 논문지
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• 제3권2호
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• pp.35-41
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• 2003

게임 엔진에서 처리하는 속성과 절차가 매우 유사한 많은 게임 소프트웨어들이 다른 게임 에서 참조하거나 재사용하지 않고 새로운 게임을 개발할 때 게임엔진 부분에 대한 중복투자 문제가 발생한다. 특히 현재 게임 소프트웨어 개발사들이 게임을 개발할 때 매우 다양한 소프트웨어 개발 프로세스를 사용하고 있는 것이 중복투자의 주된 문제점 중 하나이다. 그러므로 게임엔진에 대한 프로세스의 표준화가 되어있지 않아 현재 개발 중인 게임 소프트웨어에 다른 소프트웨어 개발과정에서 생성된 산출물을 이해하고 재사용할 수가 없다. 따라서 어느 게임 소프트웨어 개발사가 특정 게임을 개발할 때 다른 게임 소프트웨어와 동일한 게임 엔진 처리에 대하여 새롭게 분석하고 설계하는 것이 현재의 게임 소프트웨어가 안고 있는 커다란 문제점이다. 이러한 문제점을 해결하기 위해 본 논문에서는 컴포넌트 기반 개발방법을 적용할 수 있도록 게임 엔진 개발에 대한 공정개선, 구조와 관계성 분석, 계층별 모듈별 분류와 조합 방법, 저장소 구현, 프로세서 모형을 제시하였다.