• 전력전자학회논문지
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• 제4권4호
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• pp.311-317
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• 1999

본 논문에서는 SEPP-LCC형 부하 공진 고주파 인버터의 한 회로형식을 제안하고, 그 동작원리에 관해서 명확히 하였다. 제안한 인버터는 스위칭 소자 양단에 병렬로 커패시터를 추가함으로써 스위칭 소자의 턴-온과 턴-오프시에 발생하는 스위칭 손실, 노이즈, 스트레스 등을 줄일 수 있다. 범용성 있는 회로해석을 위하여 무차원화 파라미터를 도입하였고, 동작특성 및 평가를 통하여 얻은 특성치를 이용하여 회로를 설계하였다. 또한, 실험을 통하여 이론해석의 정당성을 입증하였다.

• Nuclear Engineering and Technology
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• 제41권5호
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• pp.561-574
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• 2009

First ex-vessel core catcher has been applied to the practical design of NPPs with VVER-1000 reactors built in China (Tyanvan) and India (Kudankulam) for severe accident management (SAM) and mitigation of SA consequences. The paper presents the concept and basic design of this crucible-type core catcher as well as an evaluation of its efficiency. The important role of oxidic sacrificial material is discussed. Insight into the behaviour of the molten pool, which forms in the catcher after core relocation from the reactor vessel, is provided. It is shown that heat loads on the water-cooled vessel walls are kept within acceptable limits and that the necessary margins for departure from nucleate boiling (DNB) and of vessel failure caused by thermo-mechanical stress are satisfactorily provided for.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 1999년도 추계학술대회-지능형 정보기술과 미래조직 Information Technology and Future Organization
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• pp.131-137
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• 1999

전문가시스템 개발에 있어서 지식획득 병목현상(knowledge acquisition bottleneck)은 해결해야 할 큰 걸림돌중 하나이다. 지식획득을 위한 여러 과정을 단순화하고 자동화함으로 지식공학자의 작업을 최소화하면서 전문지식을 쉽고 빠르게 획득할 수 있도록 지식획득시스템을 설계·구현한다면 전문가시스템의 대중화는 지금보다 쉽게 이루어질 것이다. 본 연구는 지식 획득시스템 설계와 구현을 위한 연구의 일환으로 기계학습의 한 방법인 PIPPER(Repeated Incremental Pruning to Produce Error Reduction)를 이용하여 규칙을 생성하고 생성된 규칙을 JESS(Justification based Expert System Shell)에서 처리하도록 하였다. 규칙을 생성하기 위한 데이터는 Bohanec이 1997년도에 만든 자동차 평가 데이터베이스(Car Evaluation Database)를 사용하여 실험하였으며, 1700여 개의 레코드에서 약 40개의 규칙이 생성되었고, 생성된 규칙은 지식베이스의 정당성을 위반하지 않으면서 실행되었다.

• 한국논리학회:학술대회논문집
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• 한국논리학회 2008년도 하계학술 발표회
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• pp.73-92
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• 2008

Describing a physical system in idealized terms involves making literally false claims about the system. Given this, it is puzzling that justified beliefs about physical systems can be formed by starting with idealized descriptions and then performing mathematical calculations. I argue that this puzzling aspect of idealizations cannot be easily removed by introducing talk of approximations. I go on to develop an account of how this curious feature of idealizations is to be understood. My account requires us to reassess what precisely we take the laws of physics to be saying, and also has consequences concerning the kind of evidence we can have for thinking that mathematics is the 'language of nature'. Finally, some critical comparisons are made with the so-called model-based account of scientific laws developed by Cartwright and Giere.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.239-244
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• 2011

Technical advancement in the field of world-class railway has brought the development of passenger safety, efficient operation and fast passenger service. The study of the railway speed-up has been progressed for a long time. As for the speed-up of trunkline railways, its design work has already promoted in some railway tacks and some track sections has already been under construction. In such a perspective we should review if the domestic signaling system is the optimal system and figure out the trend of signaling system for the speed-up that is recently applied over the world. In this way learning about justification and futurition, we should secure the national competitiveness in the long term and review the system available to international exports. Further, it is important to apply the result to the research project currently being pursued. In addition, predicting the recent international trends, we should show the direction of the future-oriented and economic signaling system.

• 아동학회지
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• 제29권5호
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• pp.113-131
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• 2008

This study examined mothers' ratings of everyday rules for their young children. Participants were 294 mothers of 2- to 5-year-old children attending kindergartens and nursery schools in Korea. Data were collected by questionnaire and were analyzed by $x^2$. Results indicated that the majority of mothers' rules for their children pertained to safety, interpersonal issues, and as children got older, social conventions. Mothers endorsed prudential justifications for safety and self-care, moral justifications for interpersonal rules, practical and moral justifications for safeguarding property, and conventional justifications for obedience/order and food/mealtime routines. Analyses of mothers' judgments of rule independence indicated that rules on interpersonal and safety issues were to be kept without exception.

• 전기전자학회논문지
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• 제3권1호
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• pp.126-132
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• 1999

The SDH (Synchronous Digital Hierarchy) has been rapidly acknowledged as a world wide transmission standard replacing the existing PDH infrastructure. A bit stuffing is used for synchronization between a PDH signal and a SDH node, and a pointer justification is used for synchronization between one SDH node and the other SDH node. During above processes - a bit stuffing and a pointer processing -, a stuffing jitter and a pointer Jitter are produced and the generated jitter can cause transmission error. In this study, a stuffing jitter and a pointer jitter are modeled and analyzed. A Sigma-Delta modulation is described and an advanced jitter reduction technique using a Sigma-Delta modulation technique in the Synchronizer, Pointer Processor and Desynchronizer is provided.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.25-30
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• 2002

The problem of qualitative reliability system is very important issue in the digitalized nuclear power plant, because the failure of its system brings about extravagant economic loss, extensive environment destruction, and fatal damage of human. Therefore this study is to develop the reliability evaluation model through the normalized scoring model by the quantitative and qualitative factors considering the advanced safety factors In the Advanced Pressurized water Reactor 1400MWe(APR 1400) under uncertainty Especially, the qualitative factors considering the information and human factors for the systematic and rational justification have been closely analyzed. The reliability evaluation model can be simply applied in real fields in order to minimize the industrial accident and human error in the digitalized nuclear power plant.

• 한국정보시스템학회지:정보시스템연구
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• 제16권1호
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• pp.65-90
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• 2007

전통적인 비용수익 분석법 (CBA approach) 과 활동기준원가계산 방법 (ABC approach)과 같은 지금까지의 방법으로는 전략적 정보시스템이나 정보 하부구조를 효과적으로 평가하고 정당화하는데 한계가 있다고 지적되어왔다. 따라서, 본 논문은 정보시스템의 하부구조를 이루고 있는 데이터 웨어하우징을 스물여섯 개의 데이터 웨어하우징 성공사례 분석을 통해서 데이터 웨어하우징이 가치사슬 모델의 각 활동에 어떻게 활용되고 있는지를 분석하고, 경쟁우위적 관점에서 이들 사례들의 공통점을 찾아내어, 데이터 웨어하우징을 경쟁우위적 관점에서 보다 효과적으로 정당화할 수 있는 모델을 제시하고 있다. 이 모델은 기존의 정보시스템 정당화에 사용되어왔던 방법들의 단점을 보완하여, 기업들이 데이터 웨어하우징이나 경쟁우위를 확보하기 위해서 구축하는 다른 정보시스템들을 경쟁우위적 관점에서 정당화하고자 할 때 유용한 도구로써, 기존의 방법들과 병행해서 사용하면 보다 효과적으로 정보시스템들을 평가하고 정당화할 수 있으리라 생각된다.

• 대한교통학회지
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• 제12권1호
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• pp.151-172
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• 1994

The objective of study is to evaluate design standards related to the allowable truck speeds, taper length and sign requirements together with the operating practices and economic justification for climbing lanes. Field surveys were carried out on seven climbing lanes, three on two-lane and four on four-lane freeways. Data collected are traffic volume, speed, usage rate and delay. It is found that current design criteria for determining the length of climbing lane, taper lengths, and traffic sign requirements must be upgraded. It is also recommended that regulations on the use of climbing lane be established to make it more effective. Further, economic analysis revealed that the climbing lane is economically justified for two-lane and four-lane freeway if the AADT is over 4,577 and 5,116 vehicles respectively.