• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.590-597
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• 2002

LNG고압펌프계통은 천연가스 고압 송출에 있어 가용도가 매우 중요한 계통이다. 본 연구에서는 현재 적용되고 있는 예방(계획)정비주기를 가용성 측면에서 재검토했다. 확률적인 운전대수와 운전 및 보전 형태에 연관된 여러제약이 고려할 때 계통 불가용도를 정량화하기 위하여 시뮬레이션 기법을 적용했다. 중도 절단된 형태의 펌프 수명 데이터를 분석해 욕조형의 고장율 함수를 도출했으며 보수시간 데이터를 분석해 확률분포모수를 구했다. 또한 주요 펌프부대설비에 대해서는 상수형의 고장율과 보전율을 도출했다. 분석된 확률모수를 작성된 시뮬레이션 모형에 입력하고 과거의 운전대수 시나리오를 설정해 실험한 결과와 실제 보수 및 운전 자료를 비교해 모형의 유효성을 보였다. 그리고 차후 예상되는 운전요구대수 시나리오를 기정하고 각 예방정비주기별로 반복 실험하여 계통의 불가용도를 보이고 적합한 예방정비주기를 도출했으며 펌프부품 교체비용의 기대 절감액을 보였다.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.81-83
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• 2005

The Reactor Protection System (RPS) is a very important system in a nuclear power plant because the system shuts down the reactor to maintain the reactor core integrity and the reactor coolant system pressure boundary if the plant conditions approach the specified safety limits. This paper describes the unavailability assessment of a digital reactor protection system using the fault tree analysis technique. The fault tree technique can be expressed in terms of combinations of the basic event failures. In this paper, a prediction method of the hardware failure rate is suggested for a digital reactor protection system. and applied to the reactor protection system being developed in Korea.

• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.29-32
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• 2004

Reliability is an important issue on the digital reactor protection system. This paper presents a Quantitative reliability evaluation method to find out an improvement effect of availability for the digital control module with a fault detection function. It is a reliability evaluation model which considers only the electronics parts ocurring a spurious reactor trip by the FMEA(Failure Mode Effect Analysis). Applying the previous and present methods to the reactor protection system, the availability factors are evaluated and compared.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.5
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• pp.593-602
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• 2004

We have developed a digital control rod control system not only to improve its performance but also to improve its reliability and speed of response so that it can replace the old fashioned analog system. However, a new developed digital control system should be tested to prove the validity by using any prototype or mock-up before application. The reliability prediction and the reliability block diagram analysis methods were adopted to verify the reliability of the developed hardware. For the case of software, especially fur a new developed control algorithm it has been tested to prove performances and validation by using a dynamic simulator and mock-up of control rod drive mechanism altogether. Here we want to present some key factors regarding to the new developed digital system with some verification procedures.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.1-11
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• 2011

The research was aimed to verify the feasibility of the model of Park-Based Mixed-Use Districts(PBMUD) around urban large park to secure private-based urban parks through the revision of the urban zoning system. The PBMUD is a type of urban zoning district in which park-oriented land use is mixed with the urban land uses of residents, advertising, business, culture, education and research. The PBMUD, delineated from and based on a new paradigm of landscape urbanism, is a new urban strategy to secure urban parks and to cultivate urban regeneration around parks and green spaces to enhance the quality of the urban landscape and to ameliorate urban environmental disasters like climate change. This study performed a questionnaire survey and analysis after a review of literature related to PBMUD. The study looked for specialists in the fields of urban planning and landscape architecture such as officials, researchers and engineers to respond to the questionnaire, which asked about degree of preference. The conclusions of this study were as follows. Firstly, specialists prefer the PBMUD at 79.3% for to 20.7% against ratio, indicating the feasibility of the model of PBMUD. The second, the most preferable reasons for the model, were the possibility of securing park space around urban parks and green spaces that assures access to park and communication with each area. The third, the main reason for non-preference for the model, was a lack of understanding of PBMUD added to the problems of unprofitable laws and regulations related to urban planning and development. These proposed a revision of the related laws and regulations such as the laws for planning and use of national land, laws for architecture etc. The fourth, the most preferred type of PBMUD, was cultural use mixed with park use in every kind of mix of land use. The degree of preference was lower in the order of use of commercial, residential, business, and education(research) when mixed with park use. The number of mixed-use amenities with in the park was found to be an indicator determining preference. The greater the number, the lower was preference frequencies, especially when related to research and business use. The fifth, the preference frequencies of the more than 70% among the respondents to the mixed-use ratio between park use and the others, was in a ratio of 60% park use and 40% other urban use. These research results will help to launch new future research subjects on the revision of zoning regulations in the laws for the planning and uses of national land and architectural law as well as criteria and indicators of subdivision planning as related to a PBMUD model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.759-767
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• 2021

Most weapons systems that are Force Integration are expensive equipment that reflects the latest technology, and the operation and maintenance cost is increasing continuously. Factors that efficiently operate and maintain these weapon systems include maintenance plans, economic costs, and repair part requirements. Among them, predicting the repair parts requirements during the life cycle in advance is an important way to increase operation and maintenance cost efficiency and operating availability. The start of requirement analysis for repair parts is a calculation of the CSP (CSP: Concurrent Spare parts, CSP hereafter) that is distributed when the weapon system is deployed. The CSP is an essential component of achieving the operating availability during this period because the weapon system aims to successfully perform a given operation mission without resupply for an initial set period. In the present study, the CSP calculation method was analyzed, reflecting the failure rate and operating time of items, but the analyzed CSP was aimed at preparing for technical failure, but in the initial operating environment, it is limited in coping with unexpected failures caused by human error. The failure is not included in the scope of free maintenance and is a serious factor in making the weapon system inoperable during the initial operation period. To prevent the inoperable status of a weapon system, CSP that considers human error is required in the initial operating environment, and the calculation criteria and measures are proposed.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.321-332
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• 2019

The purpose of this study is to identify the problems and present the improvement measures by assessing the suitability of planning of provincial natural parks on a legal basis. We assessed the suitability of 29 provincial parks to examine the suitability of park planning (special-purpose district planning and facilities planning) according to the Natural Park Act, implementation of the park projects, and registration of Korea Real estate Administration intelligence System (KRAS) for park management and obtained the following results. In the case of the park nature conservation districts among the special-purpose districts, 24.1 % (7 parks) were not feasible or decided the park facility that was larger than the planned area. The amended law requires the park cultural heritage district as a new special-purpose district, but 41.2% did not designate the district or failed to comply with the standard. Moreover, there was a problem of establishing or announcing the plan that was unsuitable for the management of park village district (former collective facilities district). Although provincial parks are categorized as the restricted area, the park facility plans still focus on regional development and tourism development, and the titles (names) of the park facilities are wrong. The law requires digitalization and disclosure of park plans, but many parks fail to abide by the law. We judge that it is necessary to develop effective provincial park planning and establish the measures to protect and manage the provincial parks.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.2
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• pp.52-62
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• 2011

By studying the classic poetry and prose with a theme of Plantain, I would like to study why Plantain has been planted in our traditional garden for a long time. Also, through this study, I want to find when Plantain was introduced to in our country. We use description study method for studying the classic poetry and prose with a theme of Plantain. As a result, we found a few things like below. First, the introduction of Plantain to our country traces back to unified Silla in the poetry of Choe Chi Won. Also, Plantain was planted and loved generally as a general garden plant in the middle of Goryeo through poetry and paintings. Second, the meaning of Plantain is like this. 1) It means development and enjoyment of arts of summer because the leaves of Plantain were used for drinking alcohol and writing and poetry instead of papers. 2) In Buddhism, Plantain was thought to awaken 'gong(空)', 'mua(無我)', and 'brevity' of lesson of Buddha by the special shape and the image of falling rain to the leaves. Also, it was used widely in Buddhist temples because of the story of 'Hye ga dan bi(慧可斷臂)'. 3) In Confucianism, it is the emblem of lesson 'a wise man tries to be strong and tries not to stop following to God'(自强不息). 4) The large leaf of Plantain is called 'bongmi(鳳尾)' thanks to the image of likeness with tails of Bongwhang(鳳凰). Third, design use of Plantain is like this. 1) The large leaf of Plantain was used for giving an image of freshness and brightness in the garden in summer. 2) Our ancestor thought 'the sound of falling rain to Plantain'(芭蕉雨聲) as a picturesque sound in summer. Also, Plantain was highly utilized because our ancestor thought Plantain is the best plant for implementing 'soundscape'. Thus, the most characteristic use of several design uses is 'acoustic use'. 3) Plantain was also planted in a indoor pot for viewing. 4) Plantain was used for making food and medicine in the palace and private house as a practical use. The limit of this study is that I mainly use the text translated into Korean of database of overall Korean classics. We hope the new things related to this study would be added up to this study by translating original texts into Korean more.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2011.10a
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• pp.5-5
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• 2011

최근에 고령화 사회에 접어들면서 건강하게 활동하며 수명을 다하는 것이 중요한 연구과제가 되고 있다. 이 때문에 영양, 운동, 스트레스, 환경 등과 관련하여 암, 당뇨병, 고혈압, 비만, 동맥경화 등 생활습관병의 극복이 사회문제가 되고 있는 실정이다. 지금까지 고려인삼의 대표적인 동물실험 및 임상학적 연구결과를 종합하여 보면 성인의 난치성 만성질환에 대해서 치료제보다는 질병을 예방하고 회복촉진에 보다 큰 효과 있음을 확인할 수 있다. 이는 인삼이 식품과 의약품의 중간에 위치한 식품의약품(Nutraceutical)의 용도로 활용할 수 있음을 시사한다. 현재까지 인삼제품에 표시되는 기능성의 내용은 약 3,000여편 이상의 약리효능에 관련된 논문이 발표되었다 하더라도 "피로회복, 면역력 증진, 혈소판 응집 억제를 통한 혈액흐름에 도움이 됩니다"이며 이외의 기능성 표시는 현재로서 원칙적으로 불가한 것으로 되어 있다. 그러나 시험물질의 규격화 및 임상시험의 검토기준을 만족시키는 과학적 자료제출에 의한 개별 평가 후 표시내용의 확대가 가능하다. 고려인삼의 다양한 성분 중 ginsenoside는 주요 약효성분으로 인정을 받고 있으며 현재 품질관리의 지표성분으로 활용되고 있다. 이러한 개별 ginsenoside의 약리작용을 보면 서로 유사 또는 상반된 효과를 보여주는 성분들이 공존하고 있어 인삼의 다양한 약리효과와 일맥상통하는 것으로 보고되고 있다. 아울러, ginsenoside는 인삼의 부위 별로 현격한 차이를 보여주기 때문에 소재의 규격화는 매우 중요하다고 판단된다. 따라서, 인삼제품 개발의 가장 중요한 조건은 의약품에 가까운 기능성식품으로 세계적인 제품을 만들기 위해서는 표준화가 선행되어야 한다. 이와 같은 조건을 잘 충족시키는 제품이 스위스 "파마톤의 진사나(백삼추출물, G115)" 제품으로 생각할 수 있다. 따라서, 고려인삼의 수출시장 확대 및 세계적인 제품을 위해서는 진사나에 필적할 수 있는 새로운 홍삼의 표준화된 추출물을 도출하는 것이 무엇보다 급선무라 생각한다. 아울러 고려인삼의 특장점 발굴을 위한 표준화 된 추출분획물, 활성성분 및 효능과 연계한 새로운 고부가가치 창출제품(식품/의약품)개발에 주력해야 할 것이다.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.685-692
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• 2005

In this study, it is surveyed and analyzed under the condition of developing GPS receiver that the present status of use and the precision of GPS receiver installed in naval vessels. Throughout interview and questionnaire with the workers in naval vessels, reliability and utilization of GPS receiver are verified. In conclusion, it is suggested that the development of GPS receiver system as well as navigation methods in naval vessels. The result of this study is as follows. Though the workers in naval vessels regard the accuracy of GPS receiver position as the fix by geographical navigation method. However, it is confirmed that its practical usage is when it is difficult to obtain the fix by geographical navigation method or R/D position or for verification. The suggested plans to develop the navigation methods from naval vessels standpoint are designing a parallel systems and introducing the GPS receiver system that functions well and is linked to the electronic navigation chart.