• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.135-145
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• 2011

Purpose: This study was conducted to investigate the actual condition of caring soft contact lens cases and the change in contamination level of lens cases by wearing and storage period of soft contact lens. Methods: The actual condition of caring soft lens cases was surveyed with sixty-three of contact lens wearers. Soft contact lenses were worn for 1, 3, 7 and 14 days, and the lenses were separately stored in 12 lens cases for 1, 3 and 7 days. The contamination level of lens cases was determined by counting the numbers of microorganisms, gram negative bacteria and fungi. Results: Only 14% of survey answerers cleaned their lens cases with a brush, rinsed and dried them upside down before next usage of lens case when those lenses were kept for a long time. Furthermore, 54% of total answerers just kept soft contact lens in the case without changing the multipurpose solution. Microorganisms, gram negative bacteria and fungi were detected in lens cases even when soft contact lens were kept for 1 day in the lens case after wearing for 1 day and cleaning it with multipurpose solution. The numbers of microorganisms, gram negative bacteria and fungi in lens cases increased with storage periods of soft contact lens, and also contamination level of lens cases was increased in accordance with wearing period of lens. In the lens cases without changing multipurpose solution, the numbers of microorganisms, gram negative bacteria and fungi increased with storage period of lens with statistical significance. Conclusions: This study showed that lens wearers' concerns on caring contact lens case were not satisfactory. As the result, the contamination of lens cases was related to increase of lens wearing and storage periods suggesting that the proper instruction and education for lens wearers are required.

• Journal of the Korean Professional Engineers Association
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• v.9 no.2
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• pp.40-43
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• 1976

The Kumgang-Pyongtaek multipurpose agricultural development project has been or iginated by president Park with the negotiation of IBRD Loan in the United States in 1965 for the development of agricultural field, The Ministry of Agricultural and fishery and Agricultural Development Corporation having finished survey and design for about 5 years for the Project, IBRD Loan and gurantee agreements were managed to signe. The project construction work has been commenced in 1970 and scheduled to be finished in 1976. About 5,618 hectares of upland reclamation which involves irrigation and bench terracing are included ill the project for the farmland expansion and establishment. It is estimated that about 25,167 metric tons of food grain production which could save foreign exchange of about 6, 100million won annually or meet food grains for about 209,000 people.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2017.10a
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• pp.72-75
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• 2017

도시농업 및 커뮤니티에 대한 사회적 관심에 편승하여 근래 도시의 커뮤니티가든(Community Garden)이 주목받고 있다. 북미의 커뮤니티가든은 농작물 생산 위주의 개인텃밭을 포괄한 지역사회의 구성원과 함께 만들어가는 오픈스페이스의 형태로, 화훼 등을 포괄하는 개념으로 간주되고 있다. 본 연구에서는 커뮤니티가든의 발상지인 북미 중에서도 가장 선진적인 사례로 손꼽히고 있는 미국 워싱턴주 시애틀(Seattle)시의 피패치(P-Patch)를 대상으로, 85개의 현장 전수조사를 통하여 공간설계 및 디자인요소를 추출하여 시사점을 도출하였다. 분석결과, 첫째 시애틀 피패치의 일반적인 디자인 구성요소는 기반시설, 지원시설, 휴게시설, 특수시설, 친환경시설 등 다섯 가지 기능으로 대별할 수 있는데, 지원시설로는 공구함(Tool Shed)이나 수전시설(Spigot)이, 친환경시설로는 도마(Cutting Board)나 퇴비함(Compost Bin)이 대부분 설치되어 있다. 둘째, 피패치의 공간구성 및 디자인적 특징으로는 이용자 수요 및 입지적 특성을 반영한 유연한 정원 설계를 들 수 있다. 셋째, 피패치는 다목적형 기능을 겸비한 복합적 공공장소로서 공공의 제도적 지원과 시민운동을 연계하는 기회를 제공하고 있다. 넷째, 지속가능성을 담보하기 위해 다양한 이해관계자(이용자, 코디네이터, 운영진, 전문가, 지역주민, 자원봉사자 등)와의 파트너십 구축, 다양한 재원 조달 방안 모색, 체계적인 모니터링 시스템 구축 및 운영을 지속하고 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.752-757
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• 2006

유역 내의 지속적인 개발과 도시화로 유출량이 증가하면서 하도의 통수능을 초과하게 됨에 따라 제방을 증고하게 되고 특히 하류부로 갈수록 유량의 급격한 증가로 제방고를 높여야 하는 악순환이 반복되었다. 이에 따라 유역의 홍수량을 하도 이외의 유역 내에서 분담하고 하도 중심의 치수 대책이 아닌 유역 전체에서 홍수를 제어해야 한다는 유역종합치수대책이 중요한 대안으로 떠오르고 있다. 유출저감시설은 이미 개발된 도시유역의 홍수량을 조절하는 데 유용할 뿐 아니라 새롭게 개발이 시행되는 유역에서는 개발로 인한 홍수 증가량을 분담하는 수단으로써 필수적으로 설치되어야 한다. 최근에는 일률적으로 임시 및 상시 저류지 등의 빈도설계를 통하여 개발 이후의 첨두유량이 개발 이전의 첨두유량 보다 크지 않도록 우수배제시스템을 설계하고 있으나 저류지와 같은 유출저감 시설을 유역출구에 설치함으로써 첨두유량만을 개발이전의 수준으로 유지할 뿐 여전히 유출량의 증가 및 홍수 도달시간이 빨라지는 문제점을 근본적으로 해결하지 못하고 있다. 본 연구에서는 현행 재해영향평가제의 법적 테두리안에서 개발사업으로 인한 증가된 홍수 저감대책을 수립하는 과정에서 몇가지 개선방안을 제시, 연구하고자 한다. 즉, 사업지구 하류하천 규모를 감안한 저류지의 적정 설계빈도의 채택과 저류지의 다목적 이용방안에 대해 검토하여 홍수재해로부터 안전하고 환경친화적인 개발사업이 될 수 있는 방안을 제시코자 한다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.481-484
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• 2008

The temperature crack of concrete structure is caused by the phenomenon which the concrete volume is restricted in the inside or outside part due th the temperature variations induced by the hydration heat of cement. And mass concrete structures are weak in temperature crack. Seongdeok multi-purpose dam is gravity dam which is being constructed in Cheongsong-gun, Gyeonsangbuk-do. Upstream cofferdam was constructed to examine the temperature crack due to hydration heat and to decide the height of placement. Therefore this study performed the hydration heat analysis of Seongdeok upstream coffer dam to analyze the hydration heat according to different height of placement and to compare with measured results.

• Nuclear Engineering and Technology
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• v.23 no.3
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• pp.328-339
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• 1991

A multi-purpose research reactor called KMRR has been developed by Korea Atomic Energy Research Institute(KAERI) to generate a maximum thermal output of 30 MW. As a part of thermal hydraulics study, pressure drop characteristics of the longitudinally finned fuel rod bundles were experimentally investigated in a recirculating water test loop. The present study is focused on the investigation of fin effects on pressure drop and the development of pressure drop correlation for the finned rod bundles in a wide range of flow conditions. Friction factor correlations for each design of the finned rod bundles are developed. The value of friction factor for the finned rod bundles was higher than the analytical solution (64/Re) of laminar circular channel new but became lower than the Blasius equation as Reynolds number was increased.

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.2
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• pp.51-60
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• 2012

This research aims to take a close look at the following topics; the ground elevation of playground, equipments of playground, and equipments around playground, and to propose the improvement measure for favorable educational environment. In consideration of the needs mentioned, the following improvement measure for playground can be suggested. First, the elevation of playground should be changed. According to Environment psychology, current playground elevation should be lowered 2 stair-long height from a classroom site. This kind of elevation change can remove unnecessary stairs, and reduces inconvenience incurred by stairs and edges, which results in considerable educational finance saving. Second, the incidental equipment within a playground needs to be improved. This fact is found out at the surveyed schools; school gathering is held at classrooms (through broadcasting) or a multi-purpose auditorium in place of a playground. The results of this study make us conclude that the most important issue to be considered in the processes of selection and investigation for school playground elevation, incidental equipments and others.

• Journal of Korean Society of Transportation
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• v.15 no.4
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• pp.35-51
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• 1997

The main objective of this research is to develop urban workers' daily travel pattern choice model. For this research, a hovel pattern choice model was empirically estimated by using a survey data collected from Kyongsan and Yeungchun City. For this research, a nested logit model structure was employed. For the model specification, it is hypothesized that urban workers' daily travel pattern choice behavior is represented by two stages of choices with single-destination or multi destination travel pattern choice as the higher stage, and the number of tours as the lower stage. The urban workers' daily travel pattern choice model developed in this research yields intuitively reasonable results. From the empirical results, it is found to be sensible to represent urban workers' daily travel patterns as the nested logit model structure Hypothesized in this research. furthermore, future directions of model development are suggested.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.404-404
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• 2018

본 연구는 홍수조절을 위한 댐의 역할과 홍수조절의 크기가 하류에 미치는 영향범위에 대해 조사하였다. 연구지역으로 낙동강을 중심으로 연구를 진행하였고 기존연구(남한강 유역)와의 비교를 통해 댐의 홍수조절 능력의 공간적 영향 범위에 대한 분석을 실시하였다. 낙동강 유역과 남한강 유역의 홍수사상은 각각 1997년부터 2010년까지의 31개의 홍수사상과 2000년부터 2010년까지의 18개의 홍수사상을 활용하였다. 남한강 유역은 횡성댐(2000년 완공)의 영향을 포함하여 분석하기 위해 2000년부터의 홍수사상을 선정하였다. 낙동강 유역은 안동댐과 임하댐의 영향을 남한강 유역은 충주댐과 횡성댐의 영향을 분석하였다. 홍수조절의 양을 분석하기 위해 홍수최대 유출치 (Peak Discharge)와 홍수유출량(Volume)을 분석하였다. 댐 자체의 홍수조절 능력을 보면 댐의 상시방류량을 넘어 조절하는 하는 경우는 남한강 댐의 경우는 종종 발생하나 낙동강내의 댐의 경우는 자주 발생하지 않는 것으로 파악됐다. 댐의 홍수조절 능력의 경우 댐의 크기와 유역의 크기를 비교분석하여 댐이 영향이 미치는 범위를 추정하였다. 댐의 영향(홍수저감율)이 10 %미만으로 조정되는 거리는 한강유역의 경우는 댐 상류의 면적의 7배에 해당하는 유역이었으나 낙동강 유역의 경우는 8.5배에 해당하는 유역면적에서 같은 영향을 나타냈다. 이는 자료의 양과 조건의 영향으로 파악된다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.2
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• pp.179-184
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• 2009

The Fuel Test Loop(FTL) which is capable of an irradiation testing under a similar operating condition to those of PWR(Pressurized Water Reactor) and CANDU(CANadian Deuterium Uranium reactor) nuclear power plants has been developed and installed in HANARO, KAERI(Korea Atomic Energy Research Institute). It consists of In-Pile Section(IPS) and Out-of Pile System(OPS). The IPS, which is located inside the pool is divided into 3-parts; the in-pool pipes, the IVA(IPS Vessel Assembly) and the support structures. The test fuel is loaded inside a double wall, inner pressure vessel and outer pressure vessel, to keep the functionality of the reactor coolant pressure boundary. The IVA is manufactured by local company and the functional test and verification were done through pressure drop, vibration, hydraulic and leakage tests. The brazing technique for the instrument lines has been checked for its functionality and performance. An IVA has been manufactured by local technique and have finally tested under high temperature and high pressure. The IVA and piping did not experience leakage, as we have checked the piping, flanges, assembly parts. We have obtained good data during the three cycle test which includes a pressure test, pressure and temperature cycling, and constant temperature.