• Journal of Korean Society of Transportation
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• v.35 no.1
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• pp.79-89
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• 2017

The purpose of this study is to analyze the current right-turn operation at signalized intersections and suggest appropriate right-turn operation strategy. From field investigation, right-turn signals have not only operated various type and shape, lacking of consistency, but also there was no clear regulations or standards. It could increase drivers' confusion and cause vehicle-to-pedestrian accidents. In order to improve pedestrian safety, there is urgent need to study the regulations and standards regarding to right-turn traffic control. This study suggests appropriate right-turn signal operation strategy. In case of permissive right-turn operation, it should be stated on regulations that red light means right-turn vehicles must stop temporarily at the stop line and then turn right. Necessary conditions for installing right-turn signal for protected operation are that there should have one or more exclusive right-turn lanes and right-turn signal face should contain the lenses with three-color arrow indication. In addition, we assort right-turn operation types as permissive, protected and protected/permissive right-turn and suggest specific signal operation strategy by the types.

• Journal of Chest Surgery
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• v.34 no.2
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• pp.133-137
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• 2001

배경: 하지에 영향을 미치는 죽상경화증은 복부대동맥과 이에 중요분지인 총장골동맥을 침범할 수 있다. 또한 국소분절을 침범할 수 있으나 다중분절은 침범할 수도 있다. 대상 및 방법: 을지의과대학교 흉부외과학 교실에서는 1995년 1월부터 1999년 12월까지 대동맥총장골동맥의 죽상경화증을 주소로 우회술을 시행받은 23례의 환자들을 후향적으로 조사하였다. 결과: 모든 환자는 남자였고 평균연령은 60.15$\pm$8.7세였다. 전 예에서 흡연의 과거력이 있었으며 동반질환으로 당뇨병 8례, 고혈합 7례, 관상동맥질환 6례, 그리고 판막질환 1례였다. 대동맥장골동맥 죽상경화증에 대한 수술방법으로는 대동맥양측대퇴동맥 우회술(7례), 대동맥양측동맥 우회술 및 대퇴동맥슬와동맥 우회술(8례), 대동맥양측대퇴동맥 우회술(2례), 액와대퇴동맥 및 고고동맥 우회술(3례), 고고동맥 우회술(3례)였다. 훌후 합병증으로 후복막상 출혈 3례, 마비성 장폐색 3례, 폐렴3례, 뇌졸중 1례, 급성신부전 2례, 창상감염 2례였다. 해부학적 우회술을 받은 환자중 3례에서 수술 사망이 발생하였다. 결론: 해부학적 우회술은 대동맥장골동맥의 폐쇄성질환에 표준적인 수술방법이지만 또한 해부학적 우회술 역시 술후 유병률 및 사망률이 낮은 좋은 수술법으로 사료된다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.1
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• pp.58-70
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• 2020

Detour behavior on the expressway means that the driver uses the local road by passing the part of the expressway which is stagnant at the time of the traffic demand such as holidays. Since the detour rate was estimated through the survey at toll gate in the past, there was a difficulty in estimating the actual detour rate due to the small sample of the survey. In this study, we use DSRC-based route travel data to conduct empirical studies on detour patterns such as the estimation of actual detour rate, the improvement of travel time using detour road, and the correlation between traffic conditions on the expressway and detour rate. On the day of Chuseok and the day before Chuseok, the analysis of Giheung-DongtanIC→OsanIC and Seopyeongtaek IC→Walgott JC showed that the use of detour roads increased gradually during the congestion of the main line and travel time reduced when using detour roads, However, when the traffic congestion of the main line is not severe, the travel time increases when using the detour roads. The correlation between the traffic condition of the expressway and the actual detour rate has a negative correlation, which is consistent with the congestion pattern of the main line. The results of this study can be used to overcome limitations of detour pattern research based on surveys in the past and to establish a detour strategy for expressway sections where traffic demand is concentrated.

• The Korean Journal of Financial Management
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• v.27 no.1
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• pp.121-156
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• 2010

Back-door-listing can be viewed both as M&A and an alternative to IPO. If IPO is an access to the capital market through regulations, back-door-listing would be the way of entering the market through trading. Back-door-listing can be a better choice considering the common wisdom that regulations hinder the functioning of free market system. One would, however, prefer IPO, for the informational asymmetry isless severe in case of IPO. This paper examines if IPO is superior to back-door-listing as to the informational efficiency. The excess buy-and-hold returns of the Kosdaq back-door-listing firms are estimated over the three-year-period since the event. They are compared against the excess buy-and-hold returns of the Kosdaq IPO firms over the same period of time. The results confirm this paper's prediction that IPO should be more information-efficient. Both IPO and back-door-listing firms start with high short-term excess returns and end up with long-term under-performance. However, back-door-listing firms show more significantly damaging long-term results. Furthermore, back-door-listing firms record poorer accounting results over the research period. These results imply that there exists fad at the time of both events and, in case of back-door-listing, this fad is reinforced by the possibility of window dressing.

• Journal of Korea Water Resources Association
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• v.44 no.11
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• pp.863-873
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• 2011

It has been known that soil erosion caused by water has been a serious problem worldwide. Thus various modeling techniques for conservationists, farmers, and other land users have been developed and utilized to estimate effects of numerous site-specific Best Management Practices on soil erosion reduction. The physical process-based WEPP model would provide both temporal and spatial estimates of soil loss within small watersheds and for hillslope profiles within small watersheds. Thus, the WEPP watershed version was applied to study watershed, located at Jawoon-ri, Gangwon to simulate diversion ditch and vegetated swale with detailed input data set. The sediment yield and runoff reduction rates reduced by 5.8% and 29.6% with diversion ditch and 9.8% and 14.5% with vegetated swale. With vegetated diversion ditch, runoff and sediment yield could be reduced by 11.8% and 40.4%, respectively. Based on the results obtained in this study, the WEPP model would be an useful tool to measure runoff and sediment yield reduction and establish site-specific sediment reduction best management plan.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.1-4
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• 2003

최근에 침입 탐지 시스템은 네트워크 보안의 강화를 위해서 방화벽과 침입탐지 시스템 상호간의 연동으로 침입자의 연결 상태를 차단하는 방법도 개발되었다. 하지만 방화벽뿐만 아니라 침입탐지 시스템도 공격자에 의한 우회공격에 대해서는 아직 상당부분 방어할 수 없다. 또한 우회공격 탐지 모듈도 기존의 IDS와 Rule의 중복이 불가피하다. 본 논문은 취약점 진단 스크립트를 통해 IDS의 취약점 진단 후 IDS우회탐지공격 시스템의 Rule을 최적화 하여 우회공격을 효율적으로 탐지 해내는 시스템을 제안한다.

• Journal of Chest Surgery
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• v.33 no.11
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• pp.906-909
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• 2000

심폐바이패스를 사용하지 않고 심장박동 상태에서 시행하는 관상동맥 우회수술은 심 비대와 좌심실 기능저하가 동반된 협증심 환자에서는 심장 뒤쪽에 위치한 관상동맥에 대한 접근이 어렵고 수술 중 혈역학적으로 불안정하여 시행하기에 어려운 경우가 많다. 우심실 보조장치 하의 심장박동 상태에서 시행하는 관상동맥 우회수술은 대동맥의 삽관을 피하고, 심폐바이패스의 합병증을 줄일 수 있으며, 심장 뒤쪽에 위치한 혈관의 문합시에도 안정된 혈역학적 상태를 유지 할 수 있어 고위험군 환자에게 도움을 줄 수 있다. 좌심실 기능저하와 심 비대가 동반된 환자에서 우심실 보조장치 하의 심장박동 상태에서 시행한 관상동맥 우회수술을 2례 시행하여 좋은 결과를 얻어 보고하고자 한다.

• Journal of Korean Society of Transportation
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• v.33 no.3
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• pp.304-314
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• 2015

Detour of metro (subway) in metropolitan area has been regarded as one of inherent elements that make entire metro system less competitive than passenger cars. However, factors affecting detour of metro line is not specified clearly when a new subway system is planned or an existing system is improved. Previous detour-related studies was reviewed for developing 'distance efficeincy evaluation model' for metro as well as its counterpart (i.e. road). Metro line 3 (orange line) of Seoul metropolitan area was applied as a case study. As a results, the most detoured OD segment is Daechi - Apgujeong and its detour factor is 1.93 which means that the distance of the metro is 1.93 times longer distance compared to the distance of the road. The metro line 3 has averagely 20% longer distance compared to road for the identical O/D pairs.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.898-901
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• 2002

It is now widely accepted that the complete arterial coronary revascularization has better short and long term results compared to coronary bypass surgery using arterial graft mixed with vein graft mainly due to its superior patency rate. However, sometimes the internal thoracic artery and other conventionally used grafts might be unavailable or it may require caution in using bilateral internal thoracic artery especially in diabetic patient because of the possible risk of the mediastinitis or other associated morbidities. Moreover, there could also be a shortage for arterial graft in case of coronary reoperation. We report our first three cases using thoracodorsal artery(TDA) as an alternative graft in complete arterial coronary revascularization.

• Journal of Chest Surgery
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• v.35 no.7
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• pp.553-555
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• 2002

Transabdominal approach in redo coronary artery bypass grafting(CABG) may avoid the risk related to repeat sternotomy. Redo CABG using this approach can be performed safely in selected cases. We report a case of redo off-pump CABG through a transabdominal approach in a 59-year-old woman with recurrent unstable angina after a previous CABG. Through a curvilinear epigastric incision, right gastroepiploic artery(RGEA) was harvested as a graft, and the RGEA-to-right coronary artery anastomosis was performed on the beating heart. A 1-day postoperative angiographic study showed the patent RGEA graft, and she was discharged on postoperative 4th day without any complication.