• Journal of the KSME
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• 제31권3호
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• pp.267-275
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• 1991

LBB 설계법은 오늘날 같이 플랜트의 대형화 및 복잡화함에 따라서, 균열이 발생하였다고 하여도 기기의 점검시 발견하지 못하는 수가 있을 것이다. 이러한 경우에 있어서 LBB 설계법은 fail safe design으로서 만일의 손상이 발생하더라도 플랜트의 안전성 및 경제성 확보를 위하여 매우 중요한 설계법이다. 이 LBB 설계법은 위에서도 설명하였듯이 선진제국에서는 상당히 연구가 진전되어 있으나, 우리나라에서는 이 분야에 연구가 전혀 없는 실정이다. 특히 에너지자원이 부족한 우리나라로서는 LNG, LPG 가스의 수입에 있어서, 이러한 저온가스를 운반할 tanker의 개발에 있어서도 LBB의 확보가 중요한 것이다. 또한 발전에너지원을 석유에만 의존하는 현재의 추세에서, 우라늄 등에 의한 원자력발전으로 대체되어 가고 있는 현재 전 발전능력의 약 50%를 의존하고 있는 실정이다. 이러한 면에서 실제의 구조물이 일시에 파단이 일어나지 않고, 파단 신뢰성이 충분히 높다는 것을 실증하여 둔다는 것은 안전성평가상 지극히 중요한 것이다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.361-365
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• 2007

전자연동장치(Interlocking System)는 열차의 안전운행 확보와 함께 수송능력과 보호향상, 정확하고 신속한 운송과 더불어 이용률을 증대하는데 중요한 역할을 한다. 철도 신호보안 설비 중에서 그 핵심을 이루는 연동장치 설비에 첨단기술인 전자, 정보처리 및 정보전송기술을 철도 신호 시스템에 도입하여 신뢰성과 안정성이 확보된 신호설비를 구현하기 위해 최근에는 마이크로프로세서를 이용한 전자연동장치 기술이 개발되었다. 본 논문에서는 전자연동장치의 필요성 및 기존설비(기계 및 계전 연동장치)의 노후화에 따른 장애 및 호환성 결여 등의 문제점들을 해결하기 위하여 전자 연동장치와 기존 계전 연동장치의 차이점을 제시 및 문제 해결방안을 고찰하고, 전자연동장치 동향을 살펴보았다.

• Journal of the Korean Operations Research and Management Science Society
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• 제36권4호
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• pp.29-41
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• 2011

As industires are evolving into a more advanced type industrial system, service economy has been more emphasized. But with the expansion of the service economy, the failure of the service has also increased. Customers flee caused by the service failure leads to from simple problems like financial loss to serious problems like damaging corporate image. Therefore, if possible, the system providing defect-free service should be established. If this is not possible, preventive measures should be taken in order to minimize the failure. The study as a tool to prevent service failure presents the concepts "service error matrix." And to confirm whether this idea is practical or not, this study investigated the hotel, one of the leading service industries, about actually occurring service failure and applied to service error matrix suggested in this study. Finally service blueprint and Poka-yoke are completed in order to reduce service failure of Y hotel which was the object of the interview for this study.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.433-437
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• 2005

The goal of our research is to develop a formal modeling methodology for supervisory and controlling systems that have artificially intelligent features. This approach is agent-based and central to the development of the model of mobility agent considering reactivity for real-time purpose and deliberation for optimal realization and safe-fail problems for critical systems like Intelligent Transportation Systems by high-level Petri net. By using nets within nets we investigate the concurrency of the system and the agent in one model without losing the needed abstraction, and synchronous channels are introduced to denote the coordination and communication. Finally an example is demonstrated.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.331-334
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• 2003

Since regulation or specification for the reinforcing method are quite ambiguous, structural design for the reinforcement can be subjectively and arbitrarily conducted. Thus, reasonable limitation and guide for the quantity of the reinforcement are required for the safe use of the structure after repair. In order to guarantee the safety of the structural member several items should be considered; reinforcing limit to avoid the brittle failure, least required strength of the existing member before reinforcement in order not to fail under the new serviceability load condition when reinforcing steel plates or CFRP sheets are harmed or subjected to fire.

• Korean Journal of Adult Nursing
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• 제17권5호
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• pp.783-792
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• 2005

Purpose: This study was conducted to meta-analyze the effects of hardiness on health-related variables. Method: After review of 19 studies performed by Korean nurses, research variables, statistical data(r or F), and other methodological data were extracted and coded. Research variables were categorized under 5 groups such as health-related behavior, well-being, adaptation, stress, and support according to conceptual similarity. Using SAS program, 20 research variables and 34 effect sizes were calculated after eliminating heterogeneous data by Q-test, Results: Effects of hardiness on whole research variables was .512 and ranged from .322 to .643 by categories. The greatest effect was obtained from well-being category, whereas the smallest effect from stress category. All effect sizes were statistically significant. But fail-safe numbers were small and failed to achieve reasonable tolerance level. Conclusion: Results of meta-analysis indicated that hardiness has a moderate effect on health-related variables. But for improving the reliability of the results by minimizing publication bias, the more hardiness studies should be done.

• Journal of Korea Association of Health Promotion
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• 제3권1호
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• pp.55-61
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• 2005

Functional constipation is regarded as a long-standing symptomatic manifestation of abnormal defecation expressed by either a reduced frequency of bowel movements and /or an altered act of evacuation. Patients with constipation can be treated with laxatives, diets and regular habits. Thorough evaluation of functional constipation is considered in those in whom conservative treatment with dietary advice and use of laxatives fails. Patients with normal colonic transit and normal anorectal function may only need reassurance, education and dietary advice with fiber supplementation. For constipated patients in whom such treatment modalities fail, laxatives including bulk-forming and osmotic agents may be used Although most laxatives, if used intermittently, are relatively safe, they must be chosen bearing in mind possible side effects, patient compliance and their action mechanisms. A subgroup of patients with slow transit through the colon ay be unresponsive to conventional laxatives, and, in these subjects, a trial with enteroprokinetics and sometimes stimulant laxatives should be attempted. This article presents our view of the assessment and pharmacologic treatment of functional constipation.

• Proceedings of the KIEE Conference
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.309-311
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• 1999

대용량의 전원단지를 포함한 전력계통에서 기간 송전선로(Route) 고장발생시 해당 계통내 동기 탈조의 불안정 현상을 보이는 발전기들의 동기탈조를 방지하기 위한 사고파급방지장치(FPPC:Fault Propagation Preventive Controller)의 기본 구성, 알고리즘 현장시험 및 적용시 설치효과에 대해 검토하였다. 전원용량이 클수록 발전기 차단 제어 완료까지 요구되는 시간은 짧아지며, 제어 요구량 또한 증가한다. 따라서 제어완료까지의 시간을 최대한 짧게 하기 위한 시스템설계 및 오동작 발생을 방지하기 위한 Fail-safe 기능을 S/W와 H/W적으로 구성하였다.

• Journal of Welding and Joining
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• 제12권3호
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• pp.82-89
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• 1994

In this paper the effect of stress ratio on the fatigue crack growth rate of aluminum alloy A5083-O was examined. The fatigue tests were carried out using CCT (center cracked tension) specimens and CT(compact tension) specimens which were subjected to 0.5 and -1.0 stress ratio respectively. The obtained results are as follows; 1) The $\DeltaK_{th}$ as the function of stress ratio R was introduced in evaluating the fatigue crack growth rate of A5083-O. 2) A new model evaluating the effect of stress ratio on the fatigue crack growth rate was developed over the region of low and high propagation rate.

• Journal of Welding and Joining
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• 제12권3호
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• pp.90-100
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• 1994

In this study the fatigue crack growth behavior was investigated for the surface cracks in aluminum alloy A5083-O plate and its weldment. Several kinds of specimens were tested at room temperature. The Eccentric specimens(E1.0, E2.5) subjected to combined stresses(tension+bending) were tested and the welded specimens with weld toes(TOE1, TOE2) were tested in order to verify the method to consider the stress concentration such as weld toe. It was ascertained that the surface crack growth property in the weld toe could be predicted by the corrected Pang's equation proposed in this study.