Design of the Structural Connection for Lightweight Structure Application

남병현,최진일,Nam, Byung Hyun,Choi, Jinnil The Korea Society for Simulation 2020 한국시뮬레이션학회 논문지 Vol.29 No.2

본 논문에서는 경량구조 적용을 위한 구조 접합부 설계를 제시하였다. 압력에 대한 구조 안정성 연구를 위하여 용접부 접합부와 볼트 접합부에 대한 모델을 설계하였다. 확립된 모델의 신뢰성 검증을 위하여, 비선형 해석을 수행하였고, 실험결과와 비교하였을 때 유사한 결과를 확인하였다. 또한 비교연구를 통하여 구조설계 재료와 적합한 용접방법을 선택하였으며, 볼트의 개수와 위치에 따른 파단하중 시뮬레이션을 진행하여 응력에 따른 안정성을 분석하였다. 마지막으로, 접합부 모델을 기반으로 경량 구조를 모델링하고 구조 해석을 수행하였다. 그 결과, 용접부와 볼트체결을 적용하여 설계된 구조가 접합부를 적용하지 않은 구조에 비해 최대응력이 31.4% 감소함을 확인하였다. 이 결과를 토대로, 경량구조의 안정성 해석 시 접합부 모델링의 필요성을 확인하였다. The structural connection design for lightweight structure application is presented in this paper. Modeling of the welding zone and the bolted connection are suggested. For reliability verification of the established models, nonlinear analysis is performed and comparisons are made with the experimental data showing good agreement. Through comparison study, suitable welding method for structure materials is investigated. Also, stability analysis is performed by fracture load simulation for different number and position of bolts. Finally, based on the structural connection models, the lightweight structure is modeled and structural analysis was performed. Stability analysis of structural connection for lightweight structure design, through combination of welding and bolting process, showed a 31.4% decrease in the maximum stress compared to the structure without the structural connections. Importance of structural connection design is highlighted for lightweight structure stability analysis.

유한요소법을 이용한 유연소자용 Au 나노구조체의 내구성 평가

남병현(Byung Hyun Nam),윤홍석(Hongseok Youn),최진일(Jinnil Choi) 한국생산제조학회 2021 한국생산제조학회지 Vol.30 No.1

In this study, the levels of durability of nanostructures for flexible devices are explored based on tensile force, bending moment, and torsion. First, for application to optical devices, aluminium nanostructures are fabricated using laser interference lithography. The optical characteristics of the fabricated nanopatterns are investigated, and the structure with the highest light transmittance is selected for durability analysis. A structural analysis model using the finite element method is then developed and its reliability is validated through a comparison with the experimental data for both polyethylene terephthalate and Au thin films. Finally, the different levels of durability of the nanostructures are investigated for application based on tensile force, bending moment, and torsion. The structural weakness of each nanostructure is explored and the durability characteristics are highlighted.

대전공단지역의 대기중 독성금속에 대한 위해도 평가

이진홍,윤미정,남병현,왕창근,강호,Lee, Jin Hong,Yun, Mi Jung,Nam, Byung Hyun,Wang, Chang Keun,Kang, Ho 한국환경영향평가학회 1999 환경영향평가 Vol.8 No.2

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and $3.46ng/m^3$ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, $293.29ng/m^3$, respectively. And the long-term arithmetic mean concentration of non-carcinogenic metal, manganese was $55.91ng/m^3$. The point risk estimate for the inhalation of carcinogenic metals was $3.6{\times}10^{-5}$, which was higher than a risk standard of $10^{-5}$. About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The point hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

적설에 따른 경량구조체의 구조해석

장한별(Han Byeoul Jang),남병현(Byung Hyun Nam),최진일(Jinnil Choi),최종민(Jong Min Choi) 대한설비공학회 2016 대한설비공학회 학술발표대회논문집 Vol.2016 No.6

석유화학단지의 휘발성 유기 화합물에 대한 확률론적 위해도 평가

이진홍(Jin Hong Lee),김윤신(Yoon Shin Kim),남병현(Byung Hyun Nam) 大韓環境工學會 1998 대한환경공학회지 Vol.20 No.6

대전공단지역의 대가중 독성금속에 대한 위해도 평가

이진홍(Jin Hong Lee),윤미정(Mi Jung Yun),남병현(Byung Hyun Nam),왕창근(Chang Keun Wang),강호(Ho Kang) 한국환경영향평가학회 1999 환경영향평가 Vol.8 No.2

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and 3.46ng/㎥ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, 293.29ng/㎥, respectively. And the long-term arithmetic mean concentration of noncarcinogenic metal, manganese was 55.91 ng/㎥. The point risk estimate for the inhalation of carcinogenic metals was 3.6 × 10^(-5), which was higher than a risk standard of 10^(-5). About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The paint hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

대전 3, 4 공단지역의 대기중 중금속의 농도

임종명,이진홍,윤미정,장미숙,남병현 忠南大學校 環境問題硏究所 1999 環境硏究 Vol.17 No.-

This research centered on seasonal analysis for the concentration of heavy metals in 5 sites within Taejon 3rd and 4th industrial Complexes. Total suspended particulates were collected on glass microfibre filters (Whatman EPM 2000) by high volume air samplers. About 20 metal elements including 13 toxic ones were analyzed by ICP-MS and ICP-AES after the pretreatment of mixed acid extraction. The following results were summarized from the research : 1) the concentrations of TSPs were 17.7∼219.6㎍/㎥ while the arithmetic mean concentration was 101.7㎍/㎥ ; 2) the arithmetic mean concentration of human carcinogen such as arsenic, hexavalent chromium and nickel subsulfide was 9.99, 6.68 and 6.13 ng/㎥ while that of probable human carcinogen such as beryllium, cadmium and lead was 0.12, 3.37, 97.65 ng/㎥, respectively.

여천공단지역의 유해 대기 오염물질에 대한 확률론적 위해도 분석

남병현,윤미정,이진홍 忠南大學校 環境問題硏究所 1998 環境硏究 Vol.16 No.-

The study centers on a probabilistic risk assessment for the inhalation of volatile organic compounds(VOCs) and toxic metals in Yeochon industrial complex. From the assessment, the 50th∼95th percentile cancer risks by VOCs for men and women are estimated to be ??∼??, ??∼??, respectively. Those percentile risks are higher than a de minimis risk of even ??. About 4% and 1% of the 95th and 50th percentile risks for both men and women come from the only human carcinogen, benzene, while about 85% and 96% come from a probable human carcinogen, 1,3-butadiene. The 50th∼95th percentile cancer risks by toxic metals for men and women are estimated to be ??∼ ??, ??∼??, respectively. Even 95th percentile risk is lower than a de minimis risk of 10-4. About 5% and 1% of the 95th and 50th percentile risks by VOCs and toxic metals for both men and women are due to heavy metals, respectively. A comparison of the probabilistic risk estimates with point risk estimate shows that the probabilistic analysis can provide a more complete assessment of risk and more useful information to risk manager and the public. However, uncertainty remains and improved Korean probabilistic density functions(PDF) are needed for factors such as airborne concentrations, inhalation rate, exposure frequencies, and cancer potency factors.

忠南大 學生들의 價値觀에 關한 硏究

徐昌源,南竝鉉 충남대학교 학생생활연구소 1985 學生生活硏究 Vol.13 No.-

대전공단지역의 대지중 독성 금속의 농도 분석

류영태,남병현,이진흥 忠南大學校 環境問題硏究所 1997 環境硏究 Vol.15 No.-

In spite of lower concentration of toxic metals in urban air, the magnitude of health risk associated with may not be smaller than that by other airborne hazardous pollutants. Especially, it has been expected that the risk from an industrial complex may be much higher by toxic metals including carcinogenic ones. However, unfortunately there has been few domestic research on the concentration profile and risk assessment of airborne toxic metals in such area. The reason may be that the final objective of studies performed before for our urban air was either source characterization or quantitative source estimation of suspended particulate matter and development of a receptor model. Thus, few investigation into the concentration distribution for toxic metals such as As, Be , Cr, Ni, Se, Sb and V has been done. Therefore, this research will focus on 2-year- analysis(twice or four times per month) by using ICP-MS and ICP-AES for the concentration of heavy metals in Taejon Industrial Complex. ICP-MS has much more excellent detection limits and reproducibility for many toxic metals than any other analytical technique. Total suspended particulates were collected on quartz fiber filters by a high volume air sampler. About 20 metal elements including 13 toxic ones were analyzed by ICP-MS and ICP-AES after the pretreatment of mixed acid extraction. As a part of the research, the following results for the period of from June to August, 1997 were summarized : (1) the geometric mean concentration of TSP was 87.28㎍/㎥ during the sampling period in the study area. The maximum was 114.16㎍/㎥ in the 4th week of August while the minimum was 47.97㎍/㎥in the first week of August; (2) much higher concentrations of Pb and Zn were noted among toxic metals and their geometric means were 288.31ng/㎥ and 153.47ng/㎥, respectively. The highest concentration of Pb was 570.99ng/㎥ in the 4th week of August while that of Zn was 279.03 ng/㎥ in the first week of June;(3) the concentration of each Ni, Mn, Zn and Fe was found to be highly correlated with that of TSP, which indicated the greater impact of man- made pollution in the area. The concentration of elements such as Al, Ca and Mg related to soil and road dust was found to be the highest in June and their correlation coefficients were estimated to be very high.