접촉불량 및 과전류의 복합적 원인에 따른 화재위험성 연구

한주환,서형원 한국화재감식학회 2018 한국화재감식학회 학회지 Vol.9 No.2

This article is a study to identify the various causes of electric fire that could occur at the terminal stage, such as poor contact and the risk of fire due to over-current. First, the fire hazard was tested for poor contact, over-current, or single cause, and then the thermal characteristics of the tightening torque changes were tested, assuming that the two causes occurred simultaneously. The experiment showed that the thermal characteristics of the terminals were significantly more apparent when the two causes worked in combination, and that the risk was higher.

북방수염하늘소(Monochamus saltuarius)의 수종별 우화시기

한주환,유종현,구창덕,윤창만,최광식,신상철,김길하,Han, Ju-Hwan,You, Jong-Hyun,Koo, Chang-Deok,Yoon, Chang-Mann,Choi, Kwang-Sik,Shin, Sang-Chul,Kim, Gil-Hah 한국응용곤충학회 2009 한국응용곤충학회지 Vol.48 No.2

충북 청원에서 2006년도부터 2008년까지 북방수염하늘소 성충의 수종(잣나무, 소나무, 낙엽송)에 따른 우화시기와 일중 우화 탈출시간을 조사하였다. 성충은 잣나무와 소나무에서 5월 초순(2${\sim}$10일)에 우화를 시작하였으며, 6월 중순(4${\sim}$20일)에 끝났다. 하지만 낙엽송에서는 5월 중순(13일)에 우화를 시작하여 5월 하순(27일)에 끝나 두 수종에 비하여 우화기간이 짧았다. 우화시기는 수컷과 암컷 간에 차이가 없었다. 2007년에 우화한 성충의 성비는 잣나무에서 0.55, 소나무 0.46, 낙엽송 0.59로 수종간 차이는 없었다. 일중 우화탈출은 24시간 내내 이루어졌고 최대 우화탈출은 12${\sim}$14:00시로 가장 높았고(22.8%), 06${\sim}$08:00시간이 가장 낮았다. 성충은 1년에 1세대 발생 비율이 98.9%이고, 2년 1세대 발생 성충의 비율은 1.1%이었다. This study was performed to investigate the emergence timing and daily emergence from the different tree species logs (Korean white pine, Pine, and Japanese larch) at Cheongwon, Chungcheongbuk-do from 2006 to 2008. Pine sawyer adults began to emerge on early May (2${\sim}$10th day) and finished on mid-June (4${\sim}$20th day) in the Korean white pine and pine logs. However, pine sawyer adults began to emerge on mid-May (13th day) and finished late May (27th day) in Japanese larch logs, Japanese larch logs shows shorter emergence timing of pine sawyer adult compare to those of other two tree species. Emergence timing shows no difference between males and females. Sex ratios of emerged adult in 2007 were 0.55 from Korean white pine, 0.46 from Pine, and 0.59 from Japanese larch; it shows no difference among tree species. Female and male adults emerged throughout 24 hrs; 22.8% of the total adults emerged from 12${\sim}$14:00 (22.8%) and adults emerged lowest from 06${\sim}$08:00. Of the adults emerged from the logs, 98.9% was univoltine and the rest was biennial which emerged next year.

학술연구논문 포스터발표 : 5분과: 임산물이용 ; 충북지역내 화살나무, 회잎나무, 고추나무, 누리장나무의 개엽특성

한주환,박용우,김두성,이귀용,구창덕,신창섭 한국임학회 2012 한국임학회 학술발표논문집 Vol.2012 No.-

학술연구논문 포스터발표 : 1분과: 산림환경, 산림생태, 수목학, 분류, 조림 ; 충북지역내 화살나무자생지 토양의 이화학적 특성과 수관 울폐율 변화

한주환,안찬기,이귀용,박용우,구창덕,신창섭 한국임학회 2013 한국임학회 학술발표논문집 Vol.2013 No.-

Molecular Dynamics Study on Atomistic Details of the Melting of Solid Argon

한주환 한국세라믹학회 2007 한국세라믹학회지 Vol.44 No.8

The atomic scale details of the melting of solid argon were monitored with the aid of molecular dynamics simulations. Thepotential energy distribution is substantially disturbed by an increase in the interatomic distance and the random offset dista ncefrom the lattice points, with increasing temperature. The potential energy barriers between the lattice points decrease in magn i-tude with the temperature. Eventually, at the melting point, these barriers can be overcome by atoms that are excited with theentropy gain acquired when the atoms obtain rotational freedom in their atomic motion, and the rotational freedom leads to thegprocess: the surface eliminates the barrier for the nucleation of the liquid phase and facilitates the melting process. Moreove r, theatomic structure of the surface varies with increasing temperature, first via surface roughening and then, before the bulk melt s,via surface melting.

Feeding and oviposition preference of the Sakhalin pine sawyer Monochamus saltuarius (Coleoptera: Cerambycidae) for various tree species

한주환,김현경,강원진,김길하 한국곤충학회 2016 Entomological Research Vol.46 No.6

Monochamus saltuarius was recently identified as an important vector of Bursaphelenchus xylophilus, the cause of pine wilt disease. In this study, M. saltuarius adults preferred different species of tree based on the longevity, ingested amount and wounded area that were determined for 90 d. Among eight tree species, the longevity of feeding by M. saltuarius was not significantly different except when feeding in Sciadopitys verticillata. However, the highest ingested amounts with the largest wounded areas were associated with Pinus koraiensis. The highest oviposition preference was in P. densiflora for the first 20 d. However, after 40 d, the oviposition highest preference was noted in P. koraiensis. For oviposition activities, M. saltuarius preferred the tree species in the following order: P. densiflora > P. koraiensis > P. rigida > Larix leptolepis. Although many oviposition scars were observed, M. saltuarius laid fewer eggs in P. rigida than other species of pine, which was related to the bark thickness. The oviposition frequencies were highest with bark 2.0–2.5 mm thick and with tree diameters of 110–130 mm. The current study increased understanding of the ecology of M. saltuarius by identifying specific tree preferences.

요소를 이용한 활성 이트리아 분말의 합성

한주환 한국세라믹학회 1997 한국세라믹학회지 Vol.34 No.12

Sinter-active yttria powders were prepared by a solution precipitation with using a self-decomposing precipitation agent NH2CONH2(urea). The cold-pressed powders can be sintered to full density and the microstructure of grains less than 200 nm at a temperature as low as 120$0^{\circ}C$. The activity of the yttria powder has been controlled by varying nucleation conditions during precipitation and by minimizing formation of aggregates. The type of precursor is decisive in preparation of a sinter-active oxide powder, and urea is desirable as a precipitation agent for an active yttrium oxide powder.

오존 발생기용 탄소복합 적극 제조기술 개발

한주환,이재춘,조수래 嶺南大學校 工業技術硏究所 2002 工業技術硏究所論文集 Vol.30 No.1

Ozone has been widely used in many industrial applications on an environmental pollution, because of its strong oxidation power. However, ozone generating electrodes whose electrolysis is performed in water will be used in environment-affinity products. In this study, on the basis of investigating all the possible materials for electrodes, We tried to develop carbon composite electrodes by various methods. the research was concentrated on the development of carbon-metal composite electrodes for proper price and bio-compatible feature.

유연 OLED디스플레이 구현을 위한 박막 봉지 기술

한주환,이성현,박진성,Han, Ju-Hwan,Lee, Seong-Hyeon,Park, Jin-Seong 한국정보디스플레이학회 2019 인포메이션 디스플레이 Vol.20 No.3

유연 OLED 디스플레이 구현을 위한 박막 봉지 기술에 대해 두 가지 관점으로 살펴보았다. 첫 번째 다층 구조를 통한 박막 봉지 특성 개선에 대한 연구는 현재까지 다양한 연구들이 진행되어 왔으며 활발히 진행 중이다. 특히 우수한 투습 방지 특성을 가지며 동시에 기계적 내구성을 잃지 않기 위해 유 무기 적층구조는 중요한 연구 주제였다. 유기물 층은 다양한 소재, 증착 방법들이 연구되었으며 무기물 층은 ?고 좋은 특성을 가지기 위해 원자층 증착법을 활용하는 것이 중요하다. 특히 원자층 증착법이 대면적 증착이 가능하며, 균일도가 높다는 점에서 향후 양산에서도 활용이 가능하다는 점에서 원자층 증착법과 분자층 증착법을 통한 유 무기 적층 구조 연구가 중요하다고 할 수 있다. 또한 막에 구조적인 변화를 주어 가해자는 응력을 최소화하는 방법을 소개하였다. 이론적으로 전체막에서 외부 응력이 가해지더라도 받는 응력이 0이 되는 중립면을 활용하면 큰 외부 응력이 막에 가해지더라도 열화가 확연히 줄어든 연구 결과들이 있었다. 결론적으로 유연 OLED 디스플레이 구현하기 위해 박막 봉지 측면에서 이루어 져야 할 연구의 방향은 소재적으로 유 무기 적층 구조를 통한 막 내구성 및 투습 방지 특성 확보가 중요하고 구조적으로는 OLED 패널 제작 시 박막 봉지 층 이외에 상부 추가되는 막의 두께와 탄성 계수를 조절하여 기계적 내구성이 낮은 백플레인 부분과 박막 봉지 부분을 중립면에 위치시켜 외부 응력으로부터 자유로워 지도록 하는 방향으로 진행될 것으로 예상된다.

고분자 절연체의 가속열화에 따른 화학적특성 및 발화위험성에 관한 연구

한주환,이준규,홍해룡 한국화재감식학회 2022 한국화재감식학회 학회지 Vol.13 No.3

In this paper, among the causes of electrical fires, the chemical properties due to thermal degradation of the wire coating, which is a polymer material, and the risk of ignition through temperature change by equivalent lifespan were analyzed. Insulated wires (HIV, 2.5SQ, single wire) used in small buildings under 500V were accelerated to deteriorate over time to produce samples for 0, 10, 20, 30, 40 years. Qualitative and quantitative analysis of insulators was performed using equipment such as strength, SEM, XRD, IR, TGA, and DSC. In addition, the temperature change by step above the allowable current was analyzed with an overcurrent tester, and through this, it was possible to confirm the risk of fire due to deterioration of insulation of old wires used in buildings. Through this study, it is possible to present the rationale for systematically introducing the replacement and repair period for old wires, and it is judged that it can be used as basic data for investigators to verify the cause of ignition due to insulation deterioration at the fire site.