• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.134-136
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• 2023

안드로이드는 오픈소스로 많은 제조 업체들이 자신들의 서비스에 맞게 커스터마이징 하기도 한다. 다만, 접근 제어 정책들을 올바르지 못하게 수정하거나 추가함에 있어서 발생하는 취약점을 통해 공격자가 해당 접근 제어 메커니즘을 우회하여 보안적 위험 문제가 발생할 수 있다. 이에 따라 안드로이드의 다양한 접근 제어 정책들을 살펴보고, 제조 업체가 추가하는 접근 제어 정책을 검사하거나 발생하는 취약점에 따라 우회할 수 있는 방법들을 찾아내는 최근 연구들의 동향을 분석하고자 하며 앞으로의 관련 연구의 지속적인 필요성을 제시한다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.1 s.2
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• pp.41-52
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• 2003

The purpose of this study was to test the effects of the pedestrian green signal adjustment on clearance of the turning vehicles impeding the through traffic flow at the signalized intersections, and thereby, suggest some operational criteria for adjustment of the pedestrian green signal. In order to test such effects, the pedestrian green time was adjusted so that it could started a few seconds later than the vehicle green time during peak hours, and thereby, the turning vehicle volume not cleared at the intersection was measured by extending the time gap by 2 seconds. (In general, the pedestrian green signal turns on at the same time as the vehicle green signal.) The results of this test can be summed up as follows; first, the longer the time gap was, the turning vehicle volume not cleared from the intersection decreased more. Second, in case there existed a storage space between intersection and crosswalk the effect of the turning vehicles on the through traffic flows was minimal. Third, at the pelican, the effect of the turning vehicles on the through traffic flow was minimal due to the structure of the intersection and the phase sequence. In conclusion, it was found that the adjustment of pedestrian green signal had the effect of enhancing the intersection operation. When adjusting the pedestrian green signal, it was deemed necessary to thoroughly survey the geometric structure of the intersection and collect the data on the turning traffic volume and thereby, apply the results of analysis flexibly to each intersection.

• Journal of Chest Surgery
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• v.42 no.6
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• pp.704-709
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• 2009

Background: We assessed the efficacy of intraoperative intra-aortic balloon pump therapy for achieving hemodynamic instability during off-pump coronary artery bypass surgery. Material and Method: We studied seven hundred ninety-six patients who underwent off-pump coronary artery bypass between January 2000 and December 2006. The patient were divided into group I (n=39), which received intraoperative intra-aortic balloon pump therapy, and group II (n=757), which did not receive intraoperative intra-aortic balloon pump therapy. Result: There were no differences in the operative mortalities (2.6%, 1/39 vs 0.8%, 6/757; p=0.195) and morbidities such as atrial fibrillation (p=0.691), stroke (p=0.908) and mediastinitis (p=0.781) between the 2 groups, although the ventilator support time, the length of the intensive care unit stay and the length of the hospital stay were longer in group I than in group II (p<0.05). Multivariate analysis failed to prove that group I was a high risk group for operative mortality (p=0.549). There were 3 intraoperative intra-aortic balloon pump-related complications in group I (7.9%). However, no longer complications occurred after 2003, when the surgeons began using a smaller sized 8 F catheter that was inserted using a sheathless technique. Conclusion: Intraoperative intra-aortic balloon pump therapy for achieving hemodynamic instability during off-pump coronary artery bypass surgery can be performed safely and it showed comparable clinical results to that of not using intraoperative intra-aortic balloon pump therapy.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2122-2123
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• 2011

대규모 발전단지의 계통연계 및 지역간 전력 융통과 대도시지역의 전력공급원 역할을 담당하기 위해 현재 전국적으로 67개의 345kV 이상 초고압변전소가 운전되고 있고, 향후에도 지속적으로 변전설비가 확충될 예정이다. 초고압 변전소에 필수적으로 설치되는 주변압기, 리액터는 그 용량에 따라 대형 중량물(345kV 변압기 66톤, 리액터 88톤 등)로 제작됨으로써 특수 운반차량을 통해서만 공장에서 현장까지 운반되고 있다. 현행 국내 도로법에서는 운반차량의 축하중이 10톤을 초과하거나 적재물 중량을 포함한 총 중량이 40톤을 초과할 경우 도로(교량)관리청의 허가를 득한 후 운반토록 규정하고 있고, 허가 조건을 맞추기 위해서는 교량보강 등의 공사를 통해 교량에 가해지는 중량을 분산시키거나 별도 우회도로를 설치하고 있다. 교량보강 공사는 교량의 종류에 따라 하부지보, 상부가교, 우회가교, 우회가도 등의 개별공법 또는 복합공사를 시행하고 있으나, 엄청난 토목공사비와 시간이 소요되고 있는 실정이다. 따라서 본 논문에서는 중량물 교량통과를 위해 대규모 토목공사 없이 운반할 수 있는 신기술 장비인 'Crossing Bridge System'에 대한 이론적 내용과 더불어 해당 기술의 특징 및 활용계획에 대해 기술하고자 한다.

• Informatization Policy
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• v.24 no.4
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• pp.68-78
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• 2017

Malicious codes are currently becoming more complex and diversified, causing various problems spanning from simple information exposure to financial or psychologically critical damages. Even though many researches have studied using reverse engineering to detect these malicious codes, malicious code developers also utilize bypassing techniques against the code analysis to cause obscurity in code understanding. Furthermore, rootkit techniques are evolving to utilize such bypassing techniques, making it even more difficult to detect infection. Therefore, in this paper, we design the analysis process as a more agile countermeasure to malicious codes that bypass analysis techniques. The proposed analysis process is expected to be able to detect these malicious codes more efficiently.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.34-42
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• 2012

Life and Property damage has increased during traffic congestion and isolation because natural disasters such as flood and landslide have occurred every year. When disaster occurs, if there is insufficient information in advance when entering the flooding areas which subsequently cause confusion. In this paper, we developed the system that could provide display of detour route using disaster information and evacuation route in disaster areas. User will receive result of analysis using smart phone application to prevent additional damages when disaster areas were entered by manager.

• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.115-130
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• 2005

This paper presents the effects of indirect costs on Life-Cycle-Cost(LCC) effective optimum design of steel-box girder bridges. The LCC formulations considered in the LCC optimization of the bridges consist of initial cost and expected rehabilitation costs including repair/replacement costs, loss of contents or fatality and injury losses, and indirect costs such as road user costs and indirect socio-economic losses. To demonstrate the LCC-effectiveness for optimum design of the bridges, an actual steel box girder bridge having two continuous spans(2@50m=100m) is considered as a numerical example. And also, in this paper, various sensitivity analyses are performed to investigate the effects of indirect costs caused by traffic conditions such as number of detour route, number of lane on detour route, length of detour route, and traffic volumes on the LCC-effective optimum design. From the numerical investigations, it may be concluded that indirect costs caused by traffic network may sensitively influence on the LCC-effective optimum design of steel-box girder bridges. Therefore, it may be stated that the traffic conditions should be considered as one of the important items in the LCC-effective optimum design of the bridges.

• Proceedings of the KOR-KST Conference
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• 2007.11a
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• pp.502-511
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• 2007

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.170.1-170.1
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.171-171
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• 2001