건설현장의 추락 및 접촉사고 방지를 위한 스마트 세이프티 센서 개발

이주희,안요섭,Lee, Juhee,Ahn, Joseph 한국건설관리학회 2021 한국건설관리학회 논문집 Vol.22 No.1

한국산업안전보건공단의 산업재해통계 보고서 최근 4년 동안의 자료를 확인하면 2017년부터 2020년 6월까지 건설현장의 재해자 수가 약 93,158명, 사망자 수가 약 1,977명으로 건설업이 재해율 총 3위, 사망률 총 1위로 높은 안전사고 추이를 보이고 있다. 그 중에서도 전체 직업군에서 추락으로 인한 사망사고 및 접촉으로 인한 사망사고는 전체 사고 유형 중 3위 안으로 빈번하게 발생하는 안전사고이다. 본 논문은 건설현장의 다양한 유형의 안전사고 중 발생 비율이 가장 높은 추락과 접촉 사고 두 유형의 안전사고를 예방하기 위해 초음파 센서를 이용한 스마트 감지 장치를 개발하여 직접 현장 작업자가 경험하게 한 결과, 설문참여 작업자의 69.5%이상이 센서의 현장 적용성에 대해 긍정적으로 평가하였으며, 이를 토대로 건설업 안전사고의 전체 비율을 감소하는데 일조 하고자 한다. According to the Korea Occupational Safety and Health Agency's (KOSHA) report on industrial accident statistics over the past four years, the number of casualties at construction sites from 2017 to June 2020 was about 93,158 and the number of deaths was about 1,977, showing a high trend of safety accidents among the eight major occupational groups, with the construction industry ranking third in total and the death rate being the highest in total. Among them, the number of deaths caused by falls in the entire occupational category is about 1,267, the highest rate of deaths due to contact is about 522, which is a frequent safety accident among the top three accident types. This paper aims to help reduce the overall proportion of construction safety accidents by developing smart safety sensing devices using ultrasonic sensors to prevent two types of safety accidents, which have the highest rate of occurrence among various types of safety accidents occurring at construction sites.

서로 다른 단면형상의 핀-휜형 방열판 최적설계

이주희(Juhee Lee),노상길(Sang-Kil Noh),오박균(Park-Kyoun Oh),임효재(Hyo-Jae Lim),박경우(Kyoungwoo Park) 대한설비공학회 2005 대한설비공학회 학술발표대회논문집 Vol.2005 No.6

DUP (Direct Underside Pressurization)을 가진 위그선의 공력특성에 관한 연구

이주희(Juhee Lee) 한국항공우주학회 2010 韓國航空宇宙學會誌 Vol.38 No.7

DUP(direct underside pressurization)는 위그선이 이륙하기 위하여 수면 위를 항주할 때 낮은 속도에서 이륙할 수 있도록 양력을 증가시키는 역할을 한다. 이러한 DUP가 위그선의 안정성과 공기역학적인 힘에 미치는 영향에 관하여 3차원 수치해석을 수행하였다. 해석에 사용된 위그선인 “Aircat”은 동체의 중심에 프로펠러가 있고 동체하부에 공기부양실이 있으며 Lippisch형의 날개와 큰 T자형의 수평꼬리날개를 가지고 있다. 저속에서 대부분의 양력은 프로펠러에 의해 가속된 공기가 동체의 가운데 통로를 통하여 공기부양실로 들어가 정체됨으로써 발생한다. 그러나 DUP에 의해 가속된 공기는 동압의 증가로 인하여 항력을 증가 시킬 뿐만 아니라 안정성에 영향을 주게 된다. DUP (direct underside pressurization) is a device that can considerably increase lift, reduce take-off speed and minimize hump drag when a WIG effect vehicle takes off on the water surface. A 3-dimensional numerical investigation of a WIG effect vehicle with DUP is performed to analyze aerodynamic characteristics and the static height stability. The model vehicle, named Aircat, consists of a propeller in the middle of a fuselage, an air chamber under the fuselage, Lippisch-type wings and a large horizontal T-tail. The lift is mainly increased by the stagnation of the accelerated air coming into the air chamber through the channel in the middle of the fuselage. However, the accelerated air increases drag as well as reduces static height stability.

미국의 對이란 비핵화 전략

이주희(Juhee Lee) 한국정치사회연구소 2022 한국과 국제사회 Vol.6 No.5

미국을 비롯한 국제사회는 평화와 안정을 추구하고 있다. 이러한 국제사회의 노력에도 불구하고 곳곳에서 테러, 핵위협 등이 난무하고 있다. 미국의 對이란 경우, 부시 행정부는 이란의 아마디네자르 핵개발 계획에 대해 강경하게 대응함으로서 대결국면이 전개되었고, 아마디네자드 대통령의 비타협적인 핵 개발 의지에 오바마 행정부는 더욱더 강한 제재를 강화하였다. 이란은 정권 교체 후, 로하니 대통령은 앞선 아마디네자드 대통령과는 달리 오바마 대통령과 협상을 통해 P5+1 방식으로 타협하게 된다. 하지만 트럼프 대통령은 이를 파기하고, 이란에 대해 강력한 경제제재로 회귀한다. 미국과 이란의 비핵화 과정은 행위자의 선택에 따른 전략에 따른 ‘주고받기(Give and Take)’식으로 전개한다. 본 연구는 미국의 對이란 비핵화 과정이 대결-타협-대결-타협을 거쳤음에도 불구하고 여전히 이란 핵문제를 해결하지 못하고 원점 제재체제로 복귀하는 이유가 무엇인지 알아보고자한다. 본 연구는 미국과 이란의 비핵화 협상 과정을 행위자 중심으로 전개하고, 비핵화에 영향을 미치는 가장 큰 요인을 제3국의 지원이라 본다. 그리고 나아가 이란의 비핵화 문제를 해결할 수 있는 유효한 방법으로 양자주의가 아닌 다자주의 협상이 중요성을 제시한다. The international community, including the United States, is seeking peace and stability. Despite the efforts of the international community, terrorism and nuclear threats are rampant everywhere. In the case of the United States against Iran, a confrontational phase developed by the Bush administration's tough response to Iran's nuclear program in Ahmadinejad, and the Obama administration strengthened sanctions even more in response to President Ahmadinejad's uncompromising will to develop nuclear weapons. After the regime change in Iran, President Rouhani, unlike the previous President Ahmadinejad, negotiated with President Obama in a P5+1 method. But President Trump overturns it and returns to strong economic sanctions against Iran. The process of denuclearization between the United States and Iran unfolds in a ‘give and take’ manner according to the strategy of the actors’ choices. This study seeks to find out why the US has returned to the original sanctions regime without resolving the Iran nuclear issue. This study develops the denuclearization negotiation process between the United States and Iran centered on the actors, and considers the biggest factor influencing denuclearization as support from third countries. Furthermore, as an effective way to resolve Iran's denuclearization issue, multilateral negotiations rather than bilateralism are suggested to be important.

한국 이공계 대학원 외국인 유학생의 언어 사용과 인식 연구

이주희 ( Lee Juhee ),조태린 ( Cho Tae-rin ) 국제한국어교육학회 2022 한국어 교육 Vol.33 No.2

The purpose of this study is to investigate, mainly in school situations, the usage of languages by international students admitted to graduate schools of science and engineering in Korea and examine their views on the usage. To this end, this study investigated which language is mainly used, English or Korean, in three significant in-school situations: classes, laboratories, and administration. Further, the level of Korean proficiency for the above three situations - private conversations with professors and colleagues and daily life outside of school - were identified. This study also asked questions about the language environment they considered in the stage of graduate school selection and the desired language environment for the university they attended. It also examined their thoughts on the recommended TOPIK grade as admission and graduation requirements. Through this survey, this study confirmed that English is used as the dominant medium of instruction and academic language in most domestic science and engineering graduate schools. This research also found that international students hardly felt the need for high-level Korean proficiency. This study concluded that English and Korean form a kind of “diglossia” at domestic graduate schools, especially science and engineering graduate schools. (Yonsei University)

클리핑방법을 이용한 non-conformal interface 경계를 갖는 열전도 해석

이주희(Juhee Lee),장진우(Jinwoo Jang),이용준(Yongjun Lee),이상환(Sanghwan Lee),이현균(Hyeonkyun Lee) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12

In CFD(Computational Fluid Dynamics) or heat transfer problem using an unstructured grid, it is possible to divide a complex domain into several simple domains. However, the grid points on the interface between two domains are not matched completely so called non-conformal mesh. Thus, mesh handling technique is needed to deal with this problem. Especially, a similar problem occurs in multi-phase or multi-material system. Since fluxes are calculated two neighbor cells sharing a surface in a finite volume method, it is difficult to calculate the proper flux. In order to overcome the problem, we employed the clipping method that calculates the connectivity and geometrical informations between non-conformal cells on the interface. The clipping method is generally used for comptuer graphics and searches the shape information of the overlapped polygons. In this study, we implemented the clipping algorithm that calculates the area and center of overlapped polygons. To validate the clipping method, the 3-dimensional heat conduction with a non-conformal interface was performed and then, it represented the reasonable solutions.

The Impact of Manure Compost Amendments on NH₃ Volatilization and Its Mechanistic Insights in a Paddy Soil during Rice Cultivation

Juhee Lee(이주희),Seongwoo Choi(최성우),Yeomyeong Lee(이여명),Sang Yoon Kim(김상윤) 한국토양비료학회 2020 한국토양비료학회 학술발표회 초록집 Vol.2020 No.10

소형가전용 팬 설계 및 전산 해석을 이용한 성능평가

이주희(Juhee Lee),김창업(Chang-Eob Kim),김성일(Sung-Il Kim),김지환(Ji-Hwan Kim) 한국항공우주학회 2017 한국항공우주학회 학술발표회 논문집 Vol.2017 No.11

일 대학 간호대학생의 시뮬레이션 교육 경험 분석

이주희(Lee, JuHee),김소선(Kim, So-Sun),여기선(Yeo, Kisun),조수진(Cho, Su Jin),김현례(Kim, Hyun Lye) 한국간호교육학회 2009 한국간호교육학회지 Vol.15 No.2

3차원 비정렬격자을 이용한 전열해석 방법론

이주희(Lee, Juhee),장진우(Jang, Jinwoo),이용준(Lee, Yongjun),최준혁(Choi, Junhyuck),이상환(Lee, Sanghwan) 한국건축친환경설비학회 2014 한국건축친환경설비학회 논문집 Vol.8 No.6

Heat transfers and related phenomena can be described by the second order partial differential equation, which cannot generally be solved except a simple domain. To make matters worse, the solution significantly dependents on the boundary conditions. The equations with analytical methods are solvable for only a limited number of cases. The known solutions are extremely useful in helping to understand heat transfer phenomena, but they rarely can be applied in engineering or design, because these solutions are not sufficiently practical. The engineer and designer have generally been forced to use numerical methods instead. To obtain an numerical solution, a discretization method, which approximates the differential equations by a system of algebraic equations is used. The approximations are applied to small domains in space and time so the numerical solution provides results at discrete locations in both space and time. The accuracy of numerical solutions is dependent on the quality of discretizations and size of cells used. The higher accuracy, the higher numerical resource are required. The balance between the accuracy and difficulty of the numerical methods is critical. The final linear equations by discretization are solved with matrix solver, which takes the most of the computation time. To reduce the computation time, the effective method for matrix solver is required. This study provides an overview of discretization, and matrix solver for the 3-dimensional numerical heat transfer.