• 해양환경안전학회지
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• 제20권3호
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• pp.277-284
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• 2014

This paper describes the application method of bumper area defined in the ship domain theory and it is to identify risky sectors in VTS(Vessel Traffic Services) area. The final goal of this work is to develop early warning system providing the location information with high traffic risks in Mokpo VTS area and to prevent the human errors of VTS Officer(VTSO). The current goal of this paper is to find evaluation and detection method of risky sectors. The ratio between overlapped bumper area of each vessels and the summing area of a designated sector, Ratio to Evaluate Risk(RER) ${\gamma}$ is used as one of evaluation and detection parameter. The usability of overlapped bumper area is testified through three kinds of scenarios for various traffic situations. The marine traffic data used in the experiments is collected by AIS(Automatic Identification System) receiver and then compiled in the SQL(Structured Query Language) Server. Through the analysis of passing vessel's tracks within the boundary of Mokpo VTS area, the total of 11 sectors are identified as evaluation unit sector. As experiment results from risk evaluation for the 11 sectors, it is clearly known that the proposed method with RER ${\gamma}$ can provide the location information of high risky sectors which are need to keep traffic tracks of vessel movements and to maintain traffic monitoring by VTSO.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권2호
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• pp.644-662
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• 2023

There are still outbreaks of COVID-19 across the world. Ships increase the risk of worldwide transmission of the virus. Close contact tracing remains as an effective method of reducing the risk of virus transmission. Therefore, close contact tracing in ship environments becomes a research topic. Exposure Notifications API (Application Programming Interface) can be used to determine the encountered location points of close contacts on ships. Location points of close contact are estimated by the encountered location points. Risky areas in ships can be calculated based on the encountered location points. The tracking of close contacts is possible with Bluetooth technology without the Internet. The Bluetooth signal can be used to judge the proximity among detecting devices by using the feature that Bluetooth has a strong signal at close range. This Bluetooth feature makes it possible to trace close contacts in ship environments. In this paper, we propose a method for close contact tracing and showing the risky area in a ship environment by combining beacon and Exposure Notification API using Bluetooth technology. This method does not require an Internet connection for tracing close contacts and can protect the personal information of close contacts.

• Journal of Preventive Medicine and Public Health
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• 제45권3호
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• pp.156-163
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• 2012

Objectives: It is necessary to examine groups carrying out sexually risky behavior because the prevalence of sexually transmitted diseases (STDs) is high among them. In this study, the prevalence of STDs among homosexuals and sexbuying men in South Korea was investigated, along with their sexual risk factors. Methods: Men who have sex with men (MSMs, n=108) were recruited in Seoul and Busan by applying the time location sampling method, while sex-buying men (n=118) were recruited from a john school in Gyeonggi province, the suburbs of Seoul. Dependent variables included past or present infection with syphilis, Chlamydia, gonorrhea, and human immunodeficiency virus. Independent variables included health behavior, social support, sexual behavior, and safe sex. Results: It was found that when the MSMs were non-drunk while having sexual intercourse (odds ratio [OR], 0.132), they showed a higher STD infection rate when they had a higher number of anal sex partners (OR, 5.872), rarely used condoms (OR, 1.980), had lower self-efficacy (OR, 0.229), and were more anxious about becoming infected with an STD (OR, 3.723). However, the men who paid for sex showed high STD infections when they had more sex partners (OR, 2.286) and lower education levels (OR, 3.028). Conclusions: STD infections among the two groups were high when they were engaged with many sex partners and not having protected sex. In other words, there was a gap in risky sex behavior within such groups, which was significantly related to the possibility of developing an STD. Therefore, the preventive intervention against STDs for these groups needs to be expanded to include management of sex behaviors.

• 한국농촌건축학회논문집
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• 제25권4호
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• pp.17-24
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• 2023

This study is about the traditional house of Kim Myeong-Gwan, the founder of Gwangsan Kim clan(光山金氏) and the 30th grandson of Heunggwang, the 49th king of the Unified Silla Dynasty. He sought a place to take refuge due to a plot and built a house in Jeongeup, adjacent to Yeonsan or Nonsan, Chungcheong-do, which is the home of the Gwangsan Kim clan. The location of old houses was analyzed through Hyeongselon(形勢論) and hyeongguklong(形局論) of Pungsu theory. The results of fengshui analysis of the house through fengshui literature that was presumed to have been used at the time are as follows.The dragon(龍) shows an auspicious condition in which the dragon vein is well connected from its roots in the Honam vein to Guksabong Mountain on Josan Mountain, Bibongsan Mountain on Sojo Mountain, and Mt. Changhasan reaching Jusan Mountain. Hyeol(穴) is a type of Wahyeol(窩穴) and is a Hwalwa(濶窩). Hyeolseong(穴星) is a Jeongche-Hyeolseong(正體穴星) and is a Suseong Hyeol(水星穴). HyeolJung(穴證) and Hyeolgi(穴忌) have the conditions to create hyeol. As for Sa(砂), the height of Hyeonmu(玄武) is not that high, but the Jujak(朱雀) is relatively high, the left blue dragon(左靑龍) is complemented by the outer blue dragon(外靑龍), and the right white tiger(右白虎) does not sufficiently surround the house. To compensate for this, Bibosu trees(裨補樹) were planted at the time of the construction of the house. As for the Water element, it appears to be auspicious as it approaches the old house in the form of a curve, but it has the disadvantage of not sufficiently surrounding the house, so an artificial pond is dug as a Bibo Pungsu(裨補風水). Through this study, it was found that Pungsu was applied as an important consideration factore in selecting the location of the house, and that Pungsu was not just a theory but had a practical effect in preserving the life and property of the family under the risky circumstances of the time.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2016년도 춘계 종합학술대회 논문집
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• pp.237-238
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• 2016

This paper describes Web-based information sharing mechanism in our hazard map creation support system. This system aims at collecting the unique information received from residents and raising resident's consciousness to disasters by recording hazardous locations where residents feel danger in case of disasters. We have implemented a mechanism to share and integrate data of each terminal through a Web server. We expect that this information sharing effects scalability and usefulness of our system by utilizing collected local hazard information of each district.

• 한국지리정보학회지
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• 제22권4호
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• pp.59-71
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• 2019

현행 「산지관리법」 에서는 산지전용허가를 위한 지형기준으로서 전용필지 내의 표고(5부 능선 미만)와 평균경사도(25°이하) 기준을 적용하여 산지의 무분별한 전용을 규제하고 있다. 그러나 표고 개념이 모호하여 5부 능선을 구획할 때 지역적 불평등을 초래할 수 있으며, 평균경사도는 지형의 급격한 사면형태를 고려할 수 없어 산사태 등과 같은 재해위험성을 판단하기 어려운 한계가 있다. 또한 표고와 경사도 이외에 필지의 환경적·생태적 중요도를 고려할 수 있는 추가적인 전용기준이 필요하다. 그러므로 본 연구에서는 기존의 경사 및 표고 기준 이외에 단순한 전용기준을 보완하기 위해 지형분류기법(Catena)을 이용한 사면유형을 전용 기준으로 추가하였으며, 1:5,000 축척의 임상도 및 산림입지토양도를 이용한 생태적 입지(영급, 경급, 토심) 기준을 제안하였다. 지형기준 개선을 위해 산지이용유형별 위험사면 포함비율을 제시함으로써 산지재해위험성을 감소시킬 수 있도록 하였다. 또한 생태적 입지를 평가하기 위해 산지전용 대상지의 영급, 경급, 토심에 대한 기준점수를 해당필지가 속한 산지유역유형별로 제시하여 산림생태계를 보전할 수 있는 기반을 마련하였다. 그리하여 최종적으로 산지의 지형 및 생태적 요소를 고려한 산지전용기준 개선방안을 제시함으로써 재해위험성 감소와 산지생태계 훼손 최소화를 유도할 수 있는 기반을 마련하도록 하였다.

• 한국ITS학회 논문지
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• 제16권4호
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• pp.122-131
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• 2017

본 연구는 최근 활용도가 주목받고 있는 드론을 활용하면 기존 현장조사장비로는 불가능했던 수준의 정밀한 영상자료 수집이 가능하다는 점에 착안하여 진행된 "드론활용 사례연구"의 하나로서, 접근로에서 황색신호 점등시 운전자의 의사결정 패턴을 분석하기 위해 드론 촬영 영상을 활용하였다. 본 연구에서는 먼저 접근로상의 딜레마구간을 파악하고, 황색신호점등 시 실제 운전자들이 정지 혹은 통과하는 의사결정 기준선을 파악하고, 이를 적정 황색신호 셋팅값에 의한 기준선과 비교하여 차이가 있는 구간을 "위험통과구간"으로 정의하고자 하였다. 또한, 이를 개선하기 위한 방법으로 황색시간 재설정 및 특정한 가이드 노면표시를 도입하여 운전자들이 안전하게 정지 혹은 통과 결정을 할 수 있도록 돕는 방안을 제안하였다.

• Earthquakes and Structures
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• 제16권4호
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• pp.437-453
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• 2019

This study investigates a new optimal placement method for viscous dampers between structures in order to prevent pounding of adjacent structures with different dynamic characteristics under earthquake effects. A relative displacement spectrum is developed in two single degree of freedom system to reveal the critical period ratios for the most risky scenario of collision using El Centro earthquake record (NS). Three different types of viscous damper design, which are classical, stair and X-diagonal model, are considered to prevent pounding on two adjacent building models. The objective function is minimized under the upper and lower limits of the damping coefficient of the damper and a target modal damping ratio. A new algorithm including time history analyses and numerical optimization methods is proposed to find the optimal dampers placement. The proposed design method is tested on two 12-storey adjacent building models. The effects of the type of damper placement on structural models, the critical period ratios of adjacent structures, the permissible relative displacement limit, the mode behavior and the upper limit of damper are investigated in detail. The results of the analyzes show that the proposed method can be used as an effective means of finding the optimum amount and location of the dampers and eliminating the risk of pounding.

• Geomechanics and Engineering
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• 제29권3호
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• pp.301-310
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• 2022

Accurate prediction of mixed ground conditions ahead of a tunnel face is of vital importance for safe excavation using tunnel boring machines (TBMs). Previous studies have primarily focused on electrical resistivity surveys from the ground surface for geotechnical investigation. In this study, an FE (finite element) numerical model was developed to simulate electrical resistivity surveys for the prediction of risky mixed ground conditions in front of a tunnel face. The proposed FE model is validated by comparing with the apparent electrical resistivity values obtained from the analytical solution corresponding to a vertical fault on the ground surface (i.e., a simplified model). A series of parametric studies was performed with the FE model to analyze the effect of geological and sensor geometric conditions on the electrical resistivity survey. The parametric study revealed that the interface slope between two different ground formations affects the electrical resistivity measurements during TBM excavation. In addition, a large difference in electrical resistivity between two different ground formations represented the dramatic effect of the mixed ground conditions on the electrical resistivity values. The parametric studies of the electrode array showed that the proper selection of the electrode spacing and the location of the electrode array on the tunnel face of TBM is very important. Thus, it is concluded that the developed FE numerical model can successfully predict the presence of a mixed ground zone, which enables optimal management of potential risks.

• 한국간담췌외과학회지
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• 제26권2호
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• pp.204-209
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• 2022

The state of intense peripancreatic inflammation in chronic pancreatitis can give rise to various vascular complications such as venous thrombosis and arterial pseudoaneurysms. Due to its intimate location with the pancreas, spleno-mesenteric-portal axis suffers the greatest blunt of thrombotic complications. Treatment modalities for such cases of chronic portal vein thrombosis have always been controversial and challenging. Medical management with anticoagulants is both risky and unsatisfactory due to presence of varices, hypersplenism, and persistence of the inflammatory pathology. Although endovascular techniques have been tried in various case reports, there are definite anatomical challenges in cases of long segment porto-mesenteric thrombosis with massive ascites. Surgical shunts have been historically described for cirrhotic and non-cirrhotic portal hypertensive patients. However, its use in patients with refractory ascites due to chronic pancreatitis induced portal vein thrombosis has not been reported in the medical literature. Here, we present a case of an extensive portal vein thrombosis with massive refractory ascites in a patient with alcohol-induced chronic pancreatitis successfully treated with a surgical mesocaval shunt using an interposition small diameter graft.