• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.724-726
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• 1996

In this paper, we propose an optimal daily operation model for the total energy system which includes cogeneration, thermal storage and electrical charger and ice storage facilities. Storing and utilizing the surplus thermal and electrical energy, the daily operation cost could be reduced and more efficient use of thermal energy could be achieved. The ice storage cooling system has a merit of reduce the electricity cost by time of day rate(peak/off-peak). And also, refrigerator can be down sized compare to the other cooling system From this model, operation costs of the sample cogeneration system with/without auxiliary facilities are obtained and compared to each other. In case study, the sensitivity of operating cost is simulated according to the variation of cogeneration production cost, electricity rate, etc.

• 대한설비공학회지:설비저널
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• 제12권4호
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• pp.240-251
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• 1983

The municipal government of Daejeon, Korea set up a plan to retrofit solar energy to the existing swimming pool. The pool was constructed in 1980, and meets the requirements of International standard. It will be used for the 1986 Asian Games and the 1988 Seoul Olymipics. The roof structure of the existing pool is to be modified to accomodate trickle solar collectors. In addition, various energy conserving ideas will be applied to the existing building structure. For the prevention of over heating of collectors on the roof, natural air convection scheme will be adopted within the collector system. Natural convection of passive type heating would be also adopted for the space heating of the pool when the system is idle. At present, the pool can be utilized only for two months a year without auxilairy heating. With oil heating, the energy cost would be too high for the normal operation. When this project completed in March 1984, it would be expected to be openable for seven months a year without a significan amount of auxiliary heating. In this project, two dimensional numerical analysis technic have been used to analyse the characterisitics of thermal performance of the swimming pool system. An experimental tat verification of the theoretical analysis have been also attempted.

• 대한환경공학회지
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• 제39권5호
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• pp.282-287
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• 2017

본 연구의 목적은 방사능 사고로 인한 오염물질 유입으로 인한 영향을 최소화하기 위한 제염제의 혼합확산장치 개발에 앞서 장치 가동으로 인한 혼합 및 확산영향을 예측하는데 있다. 유동특성분석을 위해 사용된 추적자는 방사성 동위원소는 Gy, To이며, 이를 검측하기 위해 2인치 NaI 방사선 검출기를 사용했다. 본 연구에 적용된 제염제 혼합확산장치의 임펠러는 3가지 type으로 제작하였다. 방사혼합형 임펠러는 상향류 흐름을 이용하여 수표면으로 확산이 가능하며, 최적의 조건을 찾기 위해 핀 구조를 조정하였다. 방사능 동위원소를 이용한 제염제 혼합확산장치의 유동특성을 분석한 결과, 모델별 혼합확산과 유동패턴특성을 획득하였다. Model 3 type은 별도의 Fin유도부와 보조 Fin이 구성되어 있어 다른 type의 임펠러보다 확산속도가 크고 완전혼합에 도달하는 시간이 짧게 나타났다.

• 지역연구
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• 제34권3호
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• pp.29-42
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• 2018

우리 사회의 인구성장이 둔화되고 가구형태도 1~2인의 소가구가 53.3%로 과반을 넘고 있어 향후 이를 주거단지에서 어떻게 계획으로 수용하여 적절한 주거공간을 만들어갈지가 중요해지고 있다. 따라서 본 논문에서는 소가구화 증가 추이에 대해 기존의 지구단위계획이 적절히 대응하고 있는지를 고찰하고, 소가구화에 대응한 향후 지구단위계획의 요소별 개선방안과 적용성 제고방안을 제시하고자 하였다. 이를 위해 최근 6개 주거단지를 대상으로 소가구와 관련한 지구단위계획의 지침과 내용을 분석하고 문헌고찰 및 전문가 자문 등을 통해 문제점과 개선방안을 도출하였다. 연구결과, 1인 가구 증가에 대응하여 다양한 주거유형의 지구단위계획상 반영이 필요한 사항들을 제안하고, 소형공동주택, 쉐어하우스, 독신자전용주거 등 1인 가구 주택특성에 맞는 가구 획지, 건축물 배치, 건축물 형태 및 외관 등과 관련한 계획요소도 제시하였다. 또한 무인택배시설, 게스트하우스 등 부대복리시설의 도입, 유치원 등 수요가 낮은 부대복리시설의 재검토 등 1인 가구 거주특성을 고려해야 함을 제안하였다. 제안된 계획요소와 방안들은 향후 공동주택의 지구단위계획수립지침과 운영기준 등을 작성하는 데 활용될 수 있을 것이다.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.3068-3084
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• 2021

Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to experimentally assess the damage and vibrations of NPP buildings subjected to aircraft crash. In present Part I, two shots of reduce-scaled model test of aircraft impacting on NPP building were carried out. Firstly, the 1:15 aircraft model (weighs 135 kg) and RC NPP model (weighs about 70 t) are designed and prepared. Then, based on the large rocket sled loading test platform, the aircraft models were accelerated to impact perpendicularly on the two sides of NPP model, i.e., containment and auxiliary buildings, with a velocity of about 170 m/s. The strain-time histories of rebars within the impact area and acceleration-time histories of each floor of NPP model are derived from the pre-arranged twenty-one strain gauges and twenty tri-axial accelerometers, and the whole impact processes were recorded by three high-speed cameras. The local penetration and perforation failure modes occurred respectively in the collision scenarios of containment and auxiliary buildings, and some suggestions for the NPP design are given. The maximum acceleration in the 1:15 scaled tests is 1785.73 g, and thus the corresponding maximum resultant acceleration in a prototype impact might be about 119 g, which poses a potential threat to the nuclear equipment. Furthermore, it was found that the nonlinear decrease of vibrations along the height was well reflected by the variations of both the maximum resultant vibrations and Cumulative Absolute Velocity (CAV). The present experimental work on the damage and dynamic responses of NPP structure under aircraft impact is firstly presented, which could provide a benchmark basis for further safety assessments of prototype NPP structure as well as inner systems and components against aircraft crash.

• 건축역사연구
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• 제22권2호
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• pp.43-54
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• 2013

Compared to Early Chosun Dynasty, the spatial structure of most local Eupseongs of Korea had a standardized change with the expansion and spread of the Rye-hak(禮學:a study of confucius Rite). Meanwhile in the process of rebuilding Eupseongs there was a tendency of relocation of the local government offices(官衙) and its attached facilities in terms of functions and use. Although it was PyeongSanseong Miryang Eupseong had an unreasonable spatial structure locating Gaeksa(客舍; accommodation house for visitors) in the middle of the local government office complex, and Dongheon(東軒;main office building) in the east of it before the Japanese Invasion of Korea in 1592. However with the reorganization of spatial Structure of local Eupseongs after the Japanese invasion Gaeksa was moved to the foot of Adongsan where commanded a fine view of river. Dongheon was moved to the center of Eupseong for the effective management of its auxiliary organizations. It was because road system and administrative efficiency had a serious effect on deciding the location of the local government office and its attached facilities. After the Japanese invasion Hyangchoeng(鄕廳), having been out of Eupseong, also was moved to the independent location within Eupseong separate from Dongheon and Gaeksa. It seemed to take into account the autonomy of Hyangchoeng. Dongheon, Gaeksa, and Hyangchoeng which are the crucial facilities of Milyang Eupseong were arranged at each angular point of big triangle. In order to enhance the administative efficiency, the attached administrative facilities were arranged surrounding Dongheon and Hyangchoeng. The spatial structure of Milyang Eupseong in the late Choseon dynasty was of great difference from that of uniformly organized system of early Choseon Period. It was because the development of administrative function, the pursuit of efficiency, and commercial progress had a great impact on the change of urban space.

• 한국태양에너지학회 논문집
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• 제36권5호
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• pp.73-89
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• 2016

To assure maximum economic benefits and the energy performance of solar water heating systems, the proper sizing of components and operating conditions need to be optimized. In recent years, a number of studies to design optimally solar water heating systems have been tried. This paper presents a design method for optimizing the various capacity-related and installation-related design variables based on life cycle cost using a genetic algorithm. The design variables considered in this study included the types and numbers of solar collector and auxiliary heaters; the types of storage tanks and heat exchangers; the solar collector slope; mass flow rates of the fluid on the hot and cold sides. The suggested method was applied for optimizing a solar water heating system for an elementary school in Seoul, South Korea. In addition, the effectiveness of the proposed optimization method was assessed by analyzing the obtained optimal solutions of six case studies, each of which was simulated with different solar fractions. It is observed that a trade-off between the equipment cost and the energy cost results in an optimal design that yields the lowest life cycle cost. Therefore, it could be helpful to apply the optimal solar water heating system by comparing the various design solutions obtained by using the optimization method instead of the engineer's experience and intuition.

• 한국실내디자인학회논문집
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• 제22권5호
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• pp.33-41
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• 2013

It is not surprising that senior centers are widely used nationwide as Korea becomes an aging society. This study attempts to figure out senior citizens' needs and evaluations of senior centers in terms of characteristics of their usage and spatial composition. A face to face interview using a questionnaire was conducted on 255 senior citizens who has been using senior centers located in Jangyu new city apartment housing complex. The questionnaire is composed of questions asking characteristics of their usage, evaluations of spatial composition, and respondents' demographic data. Findings are: First, it is found that many respondents visit senior centers everyday and spend 4 to 6 hours a day. Their main activities are meeting friends, taking hobbies, and dining. That is, senior centers play a pivotal role in daily lives of senior citizens. Such characteristics should be taken into account in space design when planning to build a future senior center; Second, it is found that senior centers play a role of auxiliary space for building their sense of belonging and familarity. It is found that furnitures in senior centers are worn out and safety measures are not sufficiently considered; Third, it is found that they highly evaluate flexible spacial composition that could be partitioned or extended depending on occasions even though they prefer independent space; Fourth, it is found that kitchen facilities are not large enough considering the fact that more that half of the respondents have their lunches in senior centers. Even though they do not cook for themselves kitchen space should be large enough for preparing meals simultaneously for a large number people.

• 대한공간정보학회지
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• 제6권1호
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• pp.75-90
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• 1998

본 연구에서는 하천수질관리 방안의 일환으로 수질 및 오염원등의 환경정보에 대한 데이터베이스를 구축하고, 특히 하천의 유기오염 상태를 나타내는 지표인 BOD를 중심으로 GSIS환경하에서 시간과 지점에 따라 변화되는 사항을 수치적으로는 물론 시각적으로 Simulation하였다. 또한 각종 환경관련정보의 테이터베이스 구축과 동시에 검색, 통계, 분석등에 목적을 두고 있다. 본 연구의 결과를 이용하면 일반인에게 하천의 오염상태를 쉽게 보고 이해 할 수 있게 하여 환경에 대한 관심도를 높이는 데 도움을 줄 수 있으며 돌발적인 수결오염의 발생시 대상지역 및 영향의 정도를 신속하게 파악할 수 있다. 그리고 각 지역간의 오염원현황 및 발생오염부하량의 원활한 비교와 파악이 가능하고 각 오염인자에 의한 하천의 오염의 정도를 파악할 수 있어 이에 대한 적절한 오염량 저감대책 수립의 한 기준으로 사용될 수 있을 것으로 기대된다.

• 한국지진공학회논문집
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• 제7권2호
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• pp.49-58
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• 2003

본 연구에서는 구조가 간단하고 경제적이며, 보수유지 면에서 능동형 진동제어 장치로서 매우 유리한 장점을 가지고 있는 선형모터 댐퍼(LMD : linear motor damper)를 개발하여 유니슨 기술연구소에 설치된 대형 철골구조물에 적용하였다. 개발된 LMD는 1,500kg의 가동질량을 갖고 있으며, 최대 $\pm$250mm의 변위로 움직일 수 있다. 제어 대상 시험구조물의 최저차 2개 진동형만을 가지는 축소모델을 사용하여 H$_{\infty}$ 제어로직을 설계하였다. 일련의 성능 검증시험을 통해 시험 구조물의 1, 2차 진동형에 대해 가속도 레벨이 약 l0dB 감소함을 확인하였다. 본 연구를 통해 개발된 LMD가 풍 및 지진하중을 받는 구조물의 진동제어용 제진장치로서 가능성이 있음을 확인하였다.