• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.10-13
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• 2001

이 연구에서는 2010년도 154kV, 34skV 및 765kV 송전 계통을 대상으로 전력 조류 계산 및 과도 안정도 해석 프로그램을 개발하여 새로 건설되는 대용량 원전 전력계통의 안전성을 평가하였다. 개발된 프로그램은 실계통 전체 송전망 및 전국 발전기 모선을 대상으로 전력 조류계산, 3상 단락 고장계산, 과도안정도 계산을 위하여 통합된 형태의 MS-Windows 기반 프로그램 패키지로 개발되었다. 프로그램의 효용성 검증을 위한 사례연구로 2010년의 송전계통에 대한 전력 조류를 계산하여 과도안정도를 해석한 결과 대용량 원전 전력계통은 극단적인 경우를 제외하고는 과도적으로 안정함을 확인하였다.

• Journal of KSNVE
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• v.14 no.2
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• pp.26-34
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• 2004

현재 철도는 기술의 발전과 함께 초고속 대량수송, 정시성, 안전성, 에너지효율성 및 친환경성 등의 장점을 가지는 새로운 교통수단으로 재조명되고 있다. 국내에서도 고속철도 개통과 G7고속열차의 개발 등으로 철도기술은 제 2의 도약기에 들어서고 있으며, 특히 도로교통망의 포화로 인해 철도건설수요가 계속적으로 증가할 것으로 기대되는데, 기존 수송량의 흡수 및 장기적인 관점에서 철도교통망의 확장을 도모하기 위해서는 열차의 중량화와 고속화가 제반기술의 발전과 함께 지속적으로 추진될 것으로 판단된다. 그러나 이러한 차량의 중량화와 고속화는 실질적으로 선로 주변에 발생되는 소음 및 진동의 크기를 증가시키게 되는데, 최근 들어 소음 및 진동관련 환경기준의 강화와 민원의 증가 등으로 인해 친환경적인 측면에서 적극적인 소음 진동 저감대책의 수립과 관련 기술의 적용이 요구되고 있는 상황이다.(중략)

• Journal of the Speleological Society of Korea
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• no.49
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• pp.67-72
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• 1997

오대연지는 중국 흑룡강성의 덕도현 경내에 자리잡고 있는 화산지역이다. 오대연지 주변에는 제 4기 이래 형성된 화산들이 많이 분포되어 있는데, 그 중심부에는 화산의 용암이 흘러 하천을 가로막아 구슬 모양으로 된 다섯 개의 못이 있기에 ‘오대연지’라 한다. 본 연구는 오대연지와 그 주변의 화산지형에 대해 살펴보는 데에 그 목적이 있다. 그 연구 결과는 다음과 같다 : 첫째, 본 지역은 국내ㆍ외에서 보기 드문 천연적인 화산 박물관으로서 일반적인 관광지로는 물론 화산에 관한 학술연구 활동을 진행하는 훌륭한 장소로 될 수 있다. 둘째, 본 지역의 개발에 있어서 교통조건을 하루 빨리 개선해야 한다. 하얼빈부터 덕도현성까지의 관광열차를 개통하고 오대연지의 관광서비스 시설을 늘려야 하며, 관광산업에 종사할 수 있는 인재를 많이 양성하여야 한다. 넷째, 생태환경을 잘 보존하여야 하며, 화산지역에서의 건축용 석재 채굴을 하루 빨리 중지시키고, 관광객이 화산석을 마구 채취하는 행위를 방지해야 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.11a
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• pp.832-833
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• 2023

최근 2022년 이태원 압사 사고, 2019년 김포 골드라인 개통 이후, 호전되지 않는 밀집도 및 혼잡률에 따른 안전사고 문제가 대두되고 있다. 밀집도 측정이 가능한 CCTV는 이미 존재하지만, 가격이 높고, 시스템 수정 및 적용에 제약이 존재하여 모든 장소에 적용할 수 없다는 한계점을 지니고 있다. 본 논문에서는 현재 상용화된 밀집도 측정 CCTV 시스템과는 다르게 기존 CCTV 시스템과의 상호 호환성을 기반으로 부가적인 비용이 크게 발생하지 않아 경제성이 존재하며, CCTV가 설치되어 있는 모든 장소에 적용이 가능한 확장성을 지닌 CCTV 기반 인원 밀집도 측정 시스템을 소개한다.

• International Journal of Highway Engineering
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• v.3 no.2 s.8
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• pp.131-140
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• 2001

Concrete pavement of Jungbu Expressway composed of CRCP(Continuously Reinforced Concrete Pavement) and JCP(Jointed Concrete Pavement). The CRCP was firstly constructed and applied to new expressway in Korea. It is a good source of the study to analyze the performance of CRCP and JCP because it experiences same amount of traffic and environmental loading. Up to the present, condition survey has conducted several times during 13 years but roughness measurement has not been carefully conducted. Through comparisons among several types of pavement(CRCP, JCP, Asphalt) by roughness, CRCP is superior to JCP. In addition, connected sections in the highway such as bridges and tunnels that have higher IRI values, about 5mm/m, than normal sections should be considered appropriated maintenance such as diamond grinding. The relationship between IRI and distresses carried out by Korea Highway Cooperation in 1999 skewed that the number of crack is related to IRI value in JCP, while other distresses of JCP and CRCP are not shown clearly. The comparison study with IRI values between Jungbu Expressway and GPS-3(JCP) and GPS-5(CRCP) of LTPP data also showed that roughness of Jungbu Expressway is not inferior to that of the state. Some of section showed larger values of IRI are linked with under-9round structures for passages and drainages. The overall performance considering only roughness, the CRCP is also superior to JCP in sections with under-ground tunnels.

• Progress in Medical Physics
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• v.20 no.3
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• pp.119-124
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• 2009

Stents are frequently used throughout the human body. They keep pathways open in vascular or nonvascular duct for a long time. Therefore its stability is very important factor. In recent years, aconsiderable amount of research has been carried out in order to estimate mechanical properties of the stent such as expansion pressure behavior, radial recoil and longitudinal recoil using FEM (Finite element analyses). However, published works on simulation of stent fatigue behavior using FEM are relatively rare. In this paper, a nonlinear finite-element methodwas employed to analyses the compression of a stent using external pressure and fatigue behavior. Finite element analyses for the stent system were performed using NASTRAN FX. In conclusion this paper shows how the stent is behaved in the body, and its fatigue behavior.

• Journal of the Korean Regional Science Association
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• v.32 no.1
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• pp.3-26
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• 2016

This study aims to examine the influence of the Daegu Subway Line 3 construction on apartment price fluctuation and to find the factors causing the apartment price fluctuation in the station area of the Daegu Subway Line 3. Empirical results of this study are as follows: first, the apartment price is more fluctuated or increased at the time of completion of subway construction than at the time of breaking ground; second, the opening of the Daegu Subway Line 3 has positive impact on apartment price nearby the station area of the Daegu Subway Line 3, especially apartment prices in the second station area (200-600m) are positively related to the opening of the Daegu Subway Line 3; third, medium-large size ($85-135m^2$) and large size (excess of $135m^2$) apartment are sensitively related to the apartment price fluctuation by the Daegu Subway Line 3 construction; and fourth, Buk-gu and Suseong-gu areas are the main beneficiaries. The results of this study suggest implications for tax and redistribution policies in the station areas.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.133-138
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• 1998

Choanal atresia may be membrane or bony, unilateral or bilateral. Approximately 90% of the choanal atresia are bony type. Unilateral choanal atresia often eludes the diagnosis because of the absence of subjective symptoms in the neonatal period. However, bilateral choanal atresia presents at birth with cyclic respiratory distress aggravated by feedings. So complete bilateral choanal atresia is considered as a neonatal emergency. Examinations for the diagnosis of chonal atresia include 1) attempt at passing a rubber catheter or probe through the patient s nose, 2) mirror examination of the nasopharynx, 3) digital examination of the nasopharynx, 4) X-ray examination after installation of radiopaque materal into the nasal cavity. But, computed tomography has become accepted method for evaluation of choanal atresia. Surgical repair of choanal atresia is accomplished via transnasal or transpalatal approach. Advantages of the transpalatal approach are improved exposure and the preservation of mucosal flap along the newly formed apertures. On the other hand, the transpalatal approach carries the risk of injury to the greater palatine neurovascular complex, and requires longer operative time. After careful physical and radiographic examinations, we accomplished the surgical repair of the complete bony bilateral choanal atresia via transpalatal approach without complications.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.383-390
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• 1995

This study was performed to investigate the characteristics of tear staining syndrome in poodle dogs. Schirmer tear test, fluorescein dye test and measurement of the angle of bend between vertical and horizontal bony nasolacrimal duct were conducted in both poodles and German shepherd dogs. There were no significant differences between normal and tear-stained poodles in tear formation determined by Schimer tear test. However, there was significantly higher tear production in German shepherds than that in normal poodles(p<0.05). In the fluorescein dye test for the measurement of tear excretion, the dye was observed within $14.5{\pm}6.5$ minutes after dropping of the dye in normal poodles, but was not observed even over 30 minutes in tear-stained poodles. German shepherds had rather rapid passage time($0.4{\pm}0.3$ minutes) than poodles in the dye excretion. In the measurement of the angle of bend between vertical and horizontal bony nasolacrimal duct through dacryocystorhinography, there were no significant differences between normal tear-stained poodles with showing $85.0{\pm}6.8^{\circ}$ and $89.8{\pm}6.5^{\circ}$, respectively. However, obtuse angle of bend($106.8{\pm}4.7^{\circ}$) was shown in German shepherds. These results have ascertained that tear staining syndrome of poodle dogs was not related to tear production but to the rate of tear excretion.

• Journal of Korea Planning Association
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• v.54 no.2
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• pp.54-66
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• 2019

This study analyzed whether a subway accessibility impact on house price is constant since its operation over time or not. The study was approached specifically to answer two research questions. One is "Are there significant temporal variations in the relationship between subway accessibility and housing price transacted after its opening?" The other one is "How the pattern of its temporal variation in housing price is formed as a function of the distance from the nearest station?" The study area is the subway station areas in the Daejeon metropolitan city, South Korea. Its first subway line has started to be opened in 2006 with 12 stations and then opened its additional 10 stations in 2007. It can be more appropriate to observe its impacts of subway accessibility on housing price because it has only one transit line with more than 10-year reaction term to its operation. The study employed alternative models to estimate yearly variation of subway accessibility on house price for the station areas with 500-meter and 1-kilometer radius respectively. While the study originally considered both a hedonic price model with interaction terms of its access distance to yearly transacted housing and a time-variant random coefficient model, the former model was finally selected because it is better fitted. Based on our analysis results, the reaction of house price to its transit line had significant temporal variation over time after opening. In addition, the pattern in its variation from our analysis results indicates that its capitalization impact on house price is over-estimated in its first several years after the opening. In addition, its positive capitalization impact is more effective in the 1000-meter station area than in the 500-meter one.