• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.11
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• pp.922-931
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• 2017

This research paper describes design procedures and those verification with multi-body dynamic analysis and an experiment for the development of an unprecedented type of canister cover, named as the separating cover. In order to overcome drawbacks from the precious rupture type and actuator driven cover, the separating cover was suggested. It has the simplest structure composed of the previously developed explosive bolt and a spring-lever driven system. First of all, mechanical feasibility with proposed design parameters based on mathematical modeling was confirmed through dynamic analysis and then its results showed good agreement with the followed empirical results acquired from a high speed camera. On top of that, a parametric study was conducted to identify the effect of each design parameter on separating performance. It is highly expected that this research contributes to provide military industries with a brand new canister cover having simplicity and cost efficiency and thus it will be very useful in MLRS(Multiple Launch Rocket System).

• Journal of the Korean Institute of Gas
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• v.13 no.5
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• pp.7-14
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• 2009

This study describes to analyze the pressure drop characteristics for the air-particle flow in pneumatic coal powder conveying system and to proper design of the orifice located in the system to enhance combustion efficiency in furnace of the coal-fired power plant. Usually the system consists of the straight type pipe, the curved type pipe and the elbow, which cause increase of the pressure drop. In this study, the pressure drop arised in the system with straight and curved type pipes is analyzed with interactions of motion of air flow and particles. It is realized that total pressure drop increases with increasing of the pipe length and the angle of curved type pipe due to friction loss of air and particles in the system. The program for analysis of the pressure drop and optimum design of the orifice size for air flow control in the system is developed. The result is also compared with the existing system.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.430-437
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• 2012

In order to obtain information on the design parameters of the horizontal laterals in floodplain filtration, laboratory-scale sand-box experiments were performed where the head distributions on the laterals and the groundwater profiles were measured according to the change in parameters including lateral diameter, hydraulic conductivity of the sand, water level at the well and raw-water supply rate. Measured data were analyzed using a numerical code in order to identify the discharge intensity distribution along the laterals. It was observed from the result that the lowering of the water level at the well had minimal adverse effect on the performance of the floodplain filtration. Results also elucidated that the low conveyance of the laterals to transmit the filtrate was compensated and supplemented by a natural augmentation in horizontal conveyance through the aquifer when the raw-water supply rate exceeded the adequate recovery rate. With this mechanism, the water quality is expected to improve further since the travel distance through the aquifer is amplified. Based on these findings it can be suggested that the diameter of the lateral used in the floodplain filtration may be smaller than those in riverbank/bed filtration. It was also found that the ratio between the head loss occurring in a lateral and the total head loss in the floodplain filtration was proportional to the exit velocities of the laterals, which may be used to design and/or evaluate the lateral in floodplain filtration.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.128-137
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• 2012

Chungcheoungnam-do public relation office remodeling in Hangdam-do resting place is transpotation hub. But many people are not using because discrepancy between the lack of publicity surrounding. public relation office unique role is racking with limited content and mixing operations. Thus, in public relation office to inform the development of new content items in conjunction with the development of advertisements is required. Regional branding can be the basis of the active region by unique region image to define regional identity to create regional image to secure sustainable competitiveness. The purpose of study predict remodeling aspect through analysis of existing public relation office and similar research on domestic and international facilities management practices and success factors for other public relation office. The basic design plan through a feasibility study, the first floor is specialties dealership and the second floor is cafe, public relation office and therapy space.

• Journal of Korea Water Resources Association
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• v.34 no.1
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• pp.31-43
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• 2001

The friction factor of commercial pipe varies with wide range depending on pipe type and pipe size. Various methods can describe the wide variation of friction factor with good accuracy, but they normally require an iteration process even for solution of a simple case. Power law can result in an explicit form of solver so that the power law is rigorously employed for the development of direct solution technique. The parameters used in the present form of power law are allowed to haute some variation with pipe size and Reynolds number as well as pipe type for wider coverage with good accuracy, while Hazen-Williams equation permits limited variation which accounts only for the roughness or the pipe type. Furthermore secondary loss is considered in the development of explicit equations for design of commercial pipes.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.26-33
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• 2011

Recently, the use of buried glass fiber reinforced plastic (GRP) pipes is widespread and ever increasing trend in the industry. GRP pipes are attractive for use in harsh environments, such as for the collection and transmission of liquids which are abrasive and/or corrosive. The structural behavior of a GRP pipes buried under the ground is different from that of a rigid one made of concrete or clay, for example. A GRP pipe buried under the ground is deflected circumferentially by several percent and the stresses in the pipe are mainly compressive stresses. A GRP pipes has been introduced by a number of manufacturers for selection and used by underground pipeline designers. In all cases, the modified Spangler's equation is recommended by these manufacturers for predicting the ring deflection of these pipes under dead and live loads. In this paper, the ring deflection of buried GRP pipe is evaluated and discussed based on the result of analytical investigation.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.45.4-46
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• 2016

천체투영관은 과학관이나 천문교육 시설에서 관람객이나 피교육자가 많이 찾는 인기 시설 중 하나이며 연간 200만 명이 방문하는 비형식학습의 준비된 장소이다. 현재 국내에 운영되고 있는 약 80여개의 천체투영관들은 대부분 별자리 해설과 돔영상물 상영, 과학콘서트, 천체관음악회, 전문가 강연 등의 프로그램을 운영하고 있다. 이제 국내에서도 설계된 비형식 학습 환경을 갖춘 천체투영관을 천문학 교육에 효율적으로 활용할 수 있도록 학교교육과 연계된 프로그램을 개발하고 운영하는 방안이 연구되어야 한다. 해외 과학관에서 운영되고 있는 비형식 과학교육과 학교 과학교육의 연계 프로그램의 사례 등을 조사하고 국내 천체투영관에서 활용할 수 있는 천문학 교육 연계 프로그램을 개발하는 것이 시급하다. 이번 발표에서는 개편된 교육과정이 반영된 연계 프로그램에 대해 소개하고 천체투영관을 천문학 교육에 효율적으로 활용할 수 있는 방안에 대해 관계자들의 의견을 듣고자 한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.649-653
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• 2010

일반적으로 계획 또는 설계 단계에서 수행되고 있는 관거 시설의 수리계산에는 연결관 내에서의 마찰손실만을 감안하여 수행하고 있으며, 맨홀에서의 에너지 손실은 고려되지 않는 실정이다. 그러나 연결관 내부와 맨홀의 내부는 여러 가지 수리학적 조건이 다르므로 에너지 손실이 발생하게 된다. 더욱이 직선으로 연결된 중간맨홀보다 두 개의 유입관과 한 개의 유출관으로 구성된 합류맨홀은 연결 구조상 유수교란에 의한 에너지 손실이 커질 것으로 예상됨에도 불구하고 현재 실무에서 우수 배수시설의 설계 시 직선 연결맨홀과 합류맨홀의 손실을 구별하지 않고 사용하고 있는 실정이다. 그러므로 합류맨홀에서 우수 관거 시스템의 우수 배제 능력을 증가시켜 도심지의 침수를 방지하기 위한 관거시설의 적정 설계 기준이 필요하며, 합리적인 설계 기준을 제시하기 위하여 합류 맨홀 내에서의 수두 손실을 분석할 필요가 있다. 본 연구에서는 수리 모형 실험의 물질적, 시간적 한계를 극복하기 위하여 일반적으로 3차원 유체거동의 특성분석에 많이 사용되는 Fluent 6.3 모형을 이용하여 과부하 합류 맨홀에서의 흐름특성을 수치모의 하였으며, 맨홀 내 손실수두의 변화를 계산하여 손실계수를 산정하였다. 계산된 손실계수는 수리모형 실험을 통하여 산정된 손실계수와 비교하였다. 또한 동일한 수치모의 해석 조건을 실제 합류맨홀에 적용하여 실제 합류 맨홀의 규모 변화에 따른 손실계수를 산정하였다. 수치모형의 적용 결과 맨홀 내에서의 유속변화, 수심변화 및 압력변화에 대해서는 수리모형 실험 결과와 유사한 경향을 나타내고 있으며, 수치모형에 의하여 산정된 합류 맨홀에서의 손실계수 값과 수리모형에 의하여 산정된 손실계수 값이 거의 유사하게 나타났다. 또한 동일한 수치모의 해석 조건을 실제 합류맨홀에 적용하여 합류맨홀의 규모 변화에 따른 손실계수를 산정하였으며, 산정된 손실계수는 우수관거 시스템의 설계 및 평가에 사용가능하리라 판단된다.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.90-96
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• 2009

The aim of the research is that disease database of the glycosuria and heart's blood is designed to manage the condition of the glycosuria and heart's blood patients periodically and continuously. Also we integrate patient database of existing OCS, PACS, EMR, ERP etc. and support optimal service timely that the patients want through intelligent integrated interface environment. For this, we will develop customized medical information convergence system. We construct intelligent database for disease of the glycosuria and heart's blood. And we support data integration environment for connection with existing systems - OCS, EMR, PACS etc. Also, in consideration of QoS, reliability, and expandability of customized medical information convergence system, we will design H/W, S/W, and data compatibility method.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.95-107
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• 2015

In this case study, we investigated the characteristics of pre-service secondary science teachers' curriculum design for teaching in science museums. Three pre-service secondary science teachers at a college of education in Seoul participated in this study. We have observed and recorded their teaching practices in science museums, collected all of their teaching materials, and conducted semi-structured interviews before and after teaching. All the data collected were analyzed by using the constant comparative method. The analyses of results revealed that the pre-service teachers structured their teaching in a series of pre-visit, during-visit, and post-visit as continuous activities. They attempted to reinforce students' learning experiences during the visit by providing post-visit activities, and also properly considered the principle that activity should be personally meaningful or relevant to students. However, they lacked the perceptions as well as the practical knowledge of reducing student's novelty of the science museum by providing activities prior to the visit, encouraging to engage in joint productive activities, promoting diverse social interactions, and providing students with choices and controls on their learning. On the bases of these results, we made some suggestions in pre-service teacher education for the professional development of teaching in science museum.