• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.855-859
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• 2009

In this paper, we introduce the estimation method by Risk or SIL(Safety Integrity Level) for the criterion of safety assurance and summarize each application method and target. IEC 62278(EN 50126) which is international standard for the specification and verification of the railway system RAMS indicate a criterion of safety assurance. Especially, it recommend the safety verification by continuous verification as the order of requirement establishment, design, manufacture, installation, operation, and maintenance for the equipment not easy to quantify the operation environment. In this paper, we study the SIL requirement allocation method relating to internal new system development and existing system improvement by analysing SIL recommendations which were used to understand SIL for a train control equipment in 1990s in IRSE and theoretically their allocation background. This paper help the safety management of Korea train control system to develope the quantitative management procedure as international level by analyzing the SIL requirement allocation by operation agency and the right SIL verification procedure by manufacture and indicating the example to assure safety because it is necessary for improvement and localization for the Korea train control system having highly dependence on aboard technology.

• 한국철도학회논문집
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• 제13권3호
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• pp.257-263
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• 2010

일반적으로 철도차량의 운영 유지보수 비용은 구입비용보다 높다. 따라서 철도차량의 수명주기비용(LCC)을 낮추기 위해서는 운영 및 유지보수가 용이하고 비용이 적게 드는 차량이 설계되고, 효과적이고 효율적인 운영 유지보수 지원 시스템이 공급되어야 한다. 이를 위해서 운영사는 획득초기단계에서 LCC 요구사항을제시하여 LCC가 낮은 철도차량이 설계되고 제작될 수 있도록 해야 한다. 본 연구에서는 운영사가 차량의 구매사양을 공고하고 제작사가 차량을 제작하여 공급하는 일반적인 차량의 획득절차에서 운영사와 제작사의 LCC업무 및 절차를 제시한다. 또한 이 때 사용될 수 있는 검증 가능한 LCC 산출모형을 제시한다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1996년도 학술대회
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• pp.209-212
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• 1996

In this paper, we propose to re-size images using an oblique projection operator instead of the orthogonal one in order to obtain faster, simpler, and more general algorithms. The main advantage is that it becomes perfectly feasible to use higher order models(e.g., splines of degree n 3). We develop the theoretical background and present a simple and practical implementation procedure that uses B-splines. Experiments show that the proposed algorithm consistently outperforms the standard interpolation method and that it essentially provides the same performance as the optimal procedure (least squares solution) with considerably less computations.

• 품질경영학회지
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• 제28권4호
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• pp.67-74
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• 2000

A Bayesian burn-in procedure is developed for imited failure populations in which defective items fail soon after they are put in operation and non-defective ones never fail during he technical life of the items. Sequential schemes guaranteeing pre-specified outgoing quality of a product are derived based on prior information on the quality of a product and accumulated failure information up to the decision point. A numerical example is also provided.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.844-847
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• 1989

This work describes an on-line method and procedure for calculating the fluid properties in real time while system is in operation. The method utilizes function blocks of distributed control systems. Thermodynamic relations of fluid from tables along with a fluid property formula are imbedded into the proposed signal processing block. Once the pressure and temperature measurements are entered the system provides other properties.

• Journal of Chest Surgery
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• 제28권1호
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• pp.96-99
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• 1995

Hiatal hernia is a rare disease in Korea compared to western countries. It is even rarer to find the one that requires operation after unsuccessful medical treatments. We operated three cases of hiatal hernia with gastroesophageal reflux by Belsey-Mark IV procedure. One case developed paraesophageal hernia postoperatively and we performed laparotomy to correct the complication. Postoperatively, all three cases showed satisfactory results clinically and radiographically.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.30-32
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• 2003

This paper presents the determination procedure for planning levels of harmonics in distribution systems. Planning levels should be determinated by considering the system property, operation codition, and others based on compatibility levels. In this paper international standards for harmonics are studied and the determination procedure for planning levels is deduced.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1037-1045
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• 2006

In this study, a hazard analysis was performed on the accident related work in the operational railway during 2000-2006 years in order to establish risk assesment procedure for work in the operational railway. As a result of hazard analysis, various hazard events for person accident and operation incident were identified, and risk for the each events was evaluated. Also risk matrix was structurized for setting the risk control criteria.

• Archives of Plastic Surgery
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• 제37권6호
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• pp.775-778
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• 2010

Purpose: Reconstruction of soft tissue defects with osteomyelitis in the lower third of the leg represents a challenge to plastic surgeons. Moreover, it is more arduous in multimorbid patients. One excellent option for reconstruction of these defects is to use a delayed distally based sural flap. Methods: We successfully used delayed distally based sural flap with a two-step procedure. During the first operation, radical debridement and elevation of flap were performed. The raised flap was fixed again at the donor site. The delay period ranged from seven to ten days. Between August 2008 and July 2009, we underwent operations for five patients using this technique. The size of flap varied from $10{\times}6\;cm$ to $12{\times}14\;cm$. Results: All flaps successfully survived. Partial skin loss of the grafted site was seen in two patients but no further surgical procedure was required for wound healing. Complaints of hypoesthesia on the lateral part of the foot was observed. In a three month follow-up period, hypoesthesia was resolved spontaneously. Conclusion: Delayed procedure improves the viability of distally based sural flap in high risk, critically multimorbid patients. We recommend that, if a two-stage operative approach is required, the delayed procedure should be considered.

• Journal of Chest Surgery
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• 제29권8호
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• pp.822-827
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• 1996

소아에서 대동맥 판막 질환의 경우 합리적인 수술법인 Ross술식을 적용함에 있어,우리 나라의 경우 현실적으로 이용에 어려움이 있는 Ross술식에 필요한 동종이식 판막의 사용을 배제한다는 발상으로 10마리의 15 kg가량의 돼지를 이용 REV술식 등을 시행하고 3마리의 성공 례를 3개월 이상 사육하여 성돈이 된 후 그 판막의 발육 및 기능을 관찰하였다. 대동맥 및 폐동맥 등에 협착의 소견은 없었으며, REV술식으로 사용되었던 monocusp보철편의 변형 및 심한 석회화가 관찰되어 이미 판막으로의 기능 은 상실하였으나 발육에는 큰 지장이 없는 것이 확인되어 REV와 Ross술식의 병행 수술요법이 사람에 서도 적 용될 수 있을 것으로 사료되 며, 계속 석회화 방지에 관한 연구가 진행되면 더욱 좋은 성적을 기대할 수 있겠다.