• 한국수자원학회논문집
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• 제45권8호
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• pp.839-851
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• 2012

일반적으로 수계의 용수공급능력을 평가하기 위해서는 수요량을 단계적으로 증가시키며 용수부족 여부를 검토하고 그 결과에 따라 수요량을 조정하는 시행착오법을 사용한다. 이것은 시뮬레이션 모형 뿐 아니라 최적화모형의 경우에서도 마찬가지다. 그러나 이 같은 시행착오법은 수차례의 최적화를 반복하는 번거로움을 수반한다. 이에 본 연구에서는 물 부족이 발생하지 않은 최대 용수공급능력을 보다 쉽게 찾을 수 있도록 2단계의 목표계획기반 최적화 모형을 제시하였다. 즉, 제1단계에서는 제시된 모형을 유입량 정보가 정확하다는 가정아래 최대 용수공급능력을 산정한다. 그리고 제2단계에서는 실제 용수공급상황에서는 미래 유입량에 대한 정보가 없는 점을 고려하여 최대 갈수기간에 한해 실시간 모의운영을 통하여 용수공급능력을 산정한다. 이 방법을 다기능 보가 신설되어 기존 수문환경과 차이점을 보이는 금강수계에 적용하고, 완전한 정보가 있는 경우와 그렇지 않은 경우의 결과를 비교함으로써 유입량 정보가 용수공급능력에 미치는 영향을 이해하고 평가할 수 있었다.

• Journal of Chest Surgery
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• 제24권9호
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• pp.895-902
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• 1991

The surgical experience on 18 patients with benign or malignant stricture of the esophagus who underwent isoperistaltic interposition of left colon from April 1989 to July 1991 was reviewed. During same period 22 esophageal reconstructions with colon were performed, but 3 patients who had intraabdominal adhesion in the left upper quadrant and one patient who had uncertainty of blood supply of left colic artery could not undergo iso-peristaltic interposition of left colon. There were 12 male and 6 female patients ranging from 16 to 65 years of age. 12 patients had corrosive esophageal stricture, two had cancer of esophagus, and another two had hypopharyngeal cancer. The postoperative complications developed in 7 patients [38.8%] and most frequently encountered complication was cervical anastomotic leakage, which was successfully managed with simple drainage in all cases but one malignant patient. There was no operative mortality. The esophageal reconstruction with isoperistaltic left colon resulted in good function in 14 patients[77.8%], fair in 3 patients[16.7], and poor in 1 patient[5.6%]. In this experience esophageal reconstruction using isoperistaltic left colon is a satisfactory method that can be accomplished with acceptable morbidity and mortality.

• 기술혁신연구
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• 제6권1호
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• pp.163-186
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• 1998

The psychological work environments which facilitate technology innovations in organizations are divided into two dimensions of supportive work environments and uncertain work environments. The measurement variables have significant reliability. And the confirmatory factor analysis confirm the construct validity of two dimensional work environments. Two work environments have the significant effects on motivations to the technology innovations. So, simple and hierarchical regression analyses confirm criterion-related validity. Therefore, Both of the uncertain work environments(uncertainty of external-organizational environments and tasks) and the two important work environments(supporting idea, resource supply, job autonomy) are the two important psychological work environments which indicate technology innovations in organizations. Measures for innovative psychological work environments are provided.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.545-547
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• 2005

345kV youngheung tansmission line which has been constructed in the western sea is the first and the largest marine project in the world crossing the youngheung island and the sihwa bay. It helps the stabilization of power supply greatly to cope with the rapid growth of the electric power consumption in the metropolitan areas and Gyeonggi province. Haying constructed the project successfully with the purely domestic-developed technologies, KEPCO is able to not only accumulate more advanced technologies of the marine project but also establish a bridgehead toward overseas market. It is very meaningful that we completed project successfully in spite of many difficulties including the uncertainty of the first project in the sea and strong objections from the environment groups and local residents. In this paper I will briefly introduce the project, newly developed technologies and materials.

• 시큐리티연구
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• 제7호
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• pp.213-231
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• 2004

This paper is concerned with the influence in the job satisfaction by the organization, the job specialty and the self-devotion in the special duty of private security. Today's society is required more intensive security in the diversity, the complexity and the uncertainty, but the public security service could not supply enough for what the society requires. In this circumstance more specialized and special trained security services are demanded from private security industry. With the concerns, this study is based on actual survey. The study is telling us that there is much relationship in job satisfaction between each element. Which means that 1) there is some different from personality, 2) there is much influence in self-devotion by job specialty, 3) there some effectiveness in job satisfaction by job specialty, 4) there is some influence in job satisfaction by self-devotion, and 5) job satisfaction is affected by job specialty and self-devotion.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.435-439
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• 2001

In many make-to-order production systems customers ask due date confirmed and kept. Unexpected urgent orders from valuable customers often requires short lead times, which causes existing orders in the production schedule to be delayed so that their confirmed due dates cannot be met. This Imposes significant uncertainty on the production schedule in a supply chain. In this paper, we propose a new concept of capacity reservation as a viable tool for due date promising and suggest its operational alternatives. Simulation results show that the reserved capacity scheme appears to outperform simple FCFS scheduling policy in terms of the number of valuable urgent orders accepted and total profit attained.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.940-945
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• 2009

This paper presents the design method of low order controller for the active pantograph of electric train system. The pantograph is the most playa role to supply constant current to the train. The design objectives are to have good tracking performance about reference contact force despite the stiffness variation that is like sinusoidal function concerned in train speed or span length of contact wire. In this paper, we consider stiffness variation from external disturbance of active pantograph to simplify model equation, and propose simple second-order controller which is designed by Characteristic ratio assignment(CRA) control method. Finally, we verify time response appling to model equation of real system and frequency response about parameter uncertainty like stiffness variation. it is performed by Matlab version 6.5 and Matlab simulink simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.606-608
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• 2003

경쟁적인 전력시장에서의 전력 가격은 전력에 대한 수요(Demand)와 공급(Supply)에 의한 시장원리에 의해 결정되기 때문에, 매 시각의 전력가격은 정해져 있지 않고 시장에 의해 결정된다. 이와 같이 전력가격이 가지는 가변성 및 불확실성(Volatility) 때문에 향후 전력 시장에 참여하는 사업자의 수입(Revenue) 및 수익 규모의 불확실성이 커지는 한편, 전력을 사용하는 소비자의 에너지비용도 그 불확실성이 매우 크게 증가하게 마련이다. 이러한 전력가격의 가변성(Volatility)과 불확실성(Uncertainty)이 대두됨에 따라, 외국의 경우, 가정용 부하와 같은 소규모 전력소비자를 제외한 대부분의 대규모 소비자(산업용, 상업용, 일반용 전력소비자)들은 전력가격이나 자신이 사용하고 있는 전력의 소비패턴과 같은 정보(Information)와 전략(Strategy)이 없는 경우, 예전에 비해 상당히 높은 전기요금을 지불해야 하는 상황에 처하게 되었다. 본 논문에서는 이러한 경쟁적 환경에서 직접부하제어자원을 활용하여 비용 및 위험을 관리하는 해외사례를 집중적으로 분석하고자 한다.

• 한국지능시스템학회논문지
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• 제7권5호
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• pp.77-85
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• 1997

본 연구에서는 발전기 보수유지계획 수립을 위하여 퍼지 다목적함수를 이용한 새로은 방법을 제시한다. 보수유지 지연비용의 최소화의 발전기 공급예비력의 최대화를 퍼지 다목적함수로 삼았다. 퍼지론적인 환경을 갖는 보수유지계획의 최적점을 구하기 위하여 퍼지 다목적 정수계획법을 이용하였다. 본 연구의 중요 특성은 기존의 불확실성을 갖는 크리스프적인 제약조건을 퍼지제약으로 처리함으로써 보다 유연한 해를 구할 수 있다는 점이다. 모델계통에 대한 사례연구를 통하여 이번에 개발한 수법의 효용성을 보였다.

• 대한전기학회논문지:전력기술부문A
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• 제55권11호
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• pp.453-462
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• 2006

This paper evaluates the reliability of KEPCO system using TRELSS, which is a probabilistic reliability evaluation program for large-scaled power system. In order to reflect the characteristic of KEPCO system, the sensitivity of reliability indices such as LOLP, EDLC, EENS and Energy Curtailment for variations of TRELSS parameter and input data was analyzed. Additionally, probabilistic reliability of KEPCO system reflecting sensitivity analysis results was systematically evaluated and simulated. Finally, maximum acceptable FOR of KEPCO system to satisfy reliability criterion, which meet in process of establishing the basic plan for long-term electricity supply and demand is suggested.