정온전선의 화재 위험성에 관한 연구

이정현,김시현,박예진,강신동,김재호,Jung Hyun Lee,Si Hyun Kim,Ye Jin Park,Sin Dong Kang,Jae-Ho Kim 한국안전학회 2024 한국안전학회지 Vol.39 No.3

This study examines the physical characteristics of self-regulating heating cables caused by increased temperature and fire risk due to local degradation. A thermo hygrostat system, a convection dryer, a digital multimeter (Agilent 34465 A), NI DAQ, and the LabVIEW program were used to assess the physical properties in response to temperature fluctuations. As the temperature increases, the resistance of the self-regulating heating cable increases; however, when the critical point is exceeded, the resistance sharply decreases. A problem arises when the resistance value cannot return to its original state even though the temperature is lowered to the initial state. Moreover, when the ambient temperature rises while power is applied, the resistance value initially increases, and the flowing current decreases, maintaining a constant state. However, when the critical temperature is exceeded, the flowing current increases because of a rapid decrease in the resistance value, progressing to ignition. When the resistance value decreases because of the deterioration of one local area, the total resistance value becomes less than the initial resistance value. Therefore, the flowing current increases and an ignition problem occurs at one location where deterioration occurs. Despite the sustained flames and arcs resulting from the changes in the overall physical properties of the self-regulating heating cable and resistance variations due to local decline, the fire continued as the flowing current was lower than the operating current of the circuit breaker, failing to cut the power. In the case of self-regulating heating cables and heating wires, which are the leading causes of fires in winter, efforts are needed to ensure the need for periodic maintenance and the use of KS-certified products.

생명윤리 및 안전에 관한 법률 전부개정(안)과 바이오뱅크를 이용한 연구에서의 피험자 보호방안

이정현 원광대학교 법학연구소 2010 의생명과학과 법 Vol.3 No.-

On April, 2010, the Ministry of Health and Welfare gave a legislation notice of entire revision (bill) of Bioethics and Safety Act. This entire revision is to broaden the area of bioethics policy that has been limited to embryo and gene related items and to stipulate the ethical assessment system with regards to the research on subjects and human biological materials research. A role of the bio-bank in the research of medical science and life science is essential to clarify the relation between disease and genetic information and to present a disease treatment method of new paradigm. This study searches the contents regarding the entire revision (bill) of Act regarding bioethics and safety, reviews the insured protection plan in the research using the biobank and surveys the instances of legislation for the biobank in foreign countries.

삼출성 중이염에 대한 이관 통기법의 치료효과

이정현,이재훈 圓光大學校 醫科學硏究所 1999 圓光醫科學 Vol.15 No.2

Background: Generally, the large proportion of chronic sinusitis is bilaterally affected sinus lesion but a considerable number of unilateral sinus lesions can be occurred with variant etiologies. Methods: The authors studied to determine the effect of middle ear inflation in 62 ears with otitis media with effusion. 35 ears were inflated to middle ear by politzer method on every 3 days interval during 3 months. 27 ears were treated by conservative method without inflation. The tympanometric peak pressure was used as indirect method to measure the middle ear pressure. Results: We obtained the results of improvement in 85.7% of 35ears in treatment group with middle ear inflation, and 70.3% of 27ears in the control group. The duration of recovery after treatment is the average 18±4.6days in inflation group and 32±10.4days in control group. Conclusions: Middle ear inflation has favorable therapeutic effects to treat the otitis media with effusion such as restoration of negative middle ear pressure, promotion of drainage of fluid and improvement of hearing impairment.

감포지역의 마이오세 쌍모식(bimodal) 화산활동과 화산암류의 암석학적 연구

이정현,고정선,윤성효 한국광물학회 2002 한국광물학회.한국암석학회 공동학술발표회 논문집 Vol.2002 No.-

접촉성 피부염의 한약제 치료효과 기전연구

이정현,도창호,장영우,임영진 釜山醫師會 2001 釜山醫師會誌 Vol.37 No.5

연소후 이산화탄소 포집을 위한 분리막 기술의 적용 가능성

이정현 한국막학회 2018 한국막학회 총회 및 학술발표회 Vol.2018 No.11

CO2 separation technology for carbon capture, which is one of the hot issues to reduce greenhouse gases from industrial flue gas, has been intensively investigated so far. Despite of several benefits, the membrane technology has some obstacles like large-scale module fabrication, membrane durability, need of pre-treatment or high pressure drive for its industrial application. Also, the power plant flue gas with normally 10~20% of CO2 content should be concentrated upto 99% for being compressed and liquefied to transportable CO2 by pipeline, indicating the need of high selective membrane process as well as high recovery. In this work, the possibility of membrane process for post-combustion treatment in terms of recent technology will be announced. The practically applicable process for CO2 capture also be suggested briefly.

서울시 고등학생의 외모규제에 관한 연구

이정현,이윤정 한국가정과교육학회 2006 한국가정과교육학회 학술대회 Vol.2006 No.-

해외 타이어 업체의 재편 전략

이정현,Lee, Jeong-Hyeon 대한타이어공업협회 2001 타이어 Vol.209 No.-

캡슐형 무선 내시경의 양방향 통신을 위한 CPLD 기반의 제어기 설계 및 구현

이정현,문연관,박희준,원철호,이승하,최현철,조진호,Lee Jyung Hyun,Moon Yeon Kwan,Park Hee Joon,Won Chul Ho,Lee Seung Ha,Choi Hyun Chul,Cho Jin Ho 대한의용생체공학회 2004 의공학회지 Vol.25 No.6

사람의 장속에서 영상을 획득하여 이를 체외로 전송하는 무선 내시경과 같은 초소형 텔레메트리 캡슐에서는 캡슐의 크기와 전원 공급에 많은 제약을 받는다. 캡슐을 삼킬 수 있는 크기로 제작하기 위해서는 소형의 건전지를 사용하여 캡슐이 소화관 내를 조사하는 동안 안정적인 전원 공급이 이루어지도록 해야 한다. 이를 위해서는 양방향 통신을 이용한 캡슐의 동작 및 전원 제어가 필수적이다. 본 연구에서는 캡슐형 내시경에서의 양방향 통신을 위한 CPLD (complex programmable logic device) 기반의 제어기를 설계 및 구현하였다. 캡슐 제어기는 체외의 제어기로부터 제어 명령을 전달받아 이를 수행하며 제어 동작의 수행 결과로 장내부의 영상을 획득하여 체외로 전송한다. 설계한 제어기를 컴퓨터 모의실험을 통해 설계사양을 검증하고 이를 CPLD로 구현하였다. 구현한 제어기를 캡슐형 무선 내시경에 탑재하여 동물실험을 수행하였으며 동물 실험 결과 실험 대상 동물의 체내에서 캡슐의 동작과 전원을 제어 할수 있었으며 동작제어의 결과로 장내부의 영상을 획득하여 이를 복원 할 수 있었다. In the case of a capsule that can acquire and transmit images from the intestines, the size of the module and the battery capacity in the capsule are subject to restriction. The capsule must be swallowable and the battery must maintain the stable power during the capsule travels in the gastrointestinal tract. Therefore, it is important to control the endoscope using bi-directional wireless communication. In this study, encoder and decoder CPLD modules for bi-directional capsule endoscopes were designed and implemented. The designed controller for capsule endoscope can transmit the images of GI-track from inside to outside of the body and the capsules can be controlled by external controller simultaneously. The designed and implemented controller was verified by an in-vivo animal experiments. From these experiments, it was verified that the CPLD module for bi-directional capsule endoscope satisfied the design specifications.

이주 경로 분석을 통해 살펴본 중국 국적 이주민 집중거주지의 성장 및 분화

이정현,정수열 대한지리학회 2022 대한지리학회지 Vol.57 No.2

Recently, with the increase in the number of immigrants in Korea, residential concentrations by nationality and ethnicity are growing. In particular, the Chosonjok (Korean-Chinese), who are superior in the number of immigrants, are forming residential concentrations in various regions by taking advantage of compatriots' benefits. In this study, to identify the growth and divergence process of the residential concentrations formed, considered migration paths as the driving force. Specifically, It analyzed the migration paths of Chinese nationality immigrants (Chosonjok and Han Chinese) as the case of residential concentrations based in Garibong-dong, Daerim-dong in Seoul, and Godeung-dong Maesan-dong in Suwon. The results are as follows. Firstly, Daerim-dong serves as nodal regions in the migration paths of Chinese immigrants. Secondly, the migration network of Chosonjok is more developed than the case of Han Chinese. Thirdly, it confirmed the development of Chinese nationality's migration paths that connected to Garibong-dong (proto-type), Daerim-dong (expanded-type), Godeung-dong, and Maesan-dong (relocation-type). That is a driver as Chosonjok residential concentrations are grown and diverged. This study is significant in identifying the mechanism of growth and divergence of residential concentrations in the same nationality and same ethnicity. 최근 국내 외국인 이주민의 수적 증가와 더불어 국적·민족별 집중거주지들이 성장하고 있다. 특히 수적으로 우세한 조선족은 동포로서의 이점을 활용하여 여러 지역에 걸쳐 집중거주지들을 형성하고 있다. 본 연구는 이렇게 형성된 집중거주지의 성장 및 분화 과정을 규명하고자 그 동인인 이주 경로를 고찰하였다. 구체적으로 서울시 가리봉동과 대림동을 그리고 수원시의 고등동·매산동에 자리잡은 중국 국적 이주민(조선족, 한족) 집중거주지를 사례로 그들의 이주 경로를 분석하였다. 연구 결과는 다음과 같다. 첫째, 중국 이주민의 국내 이주 경로에서 대림동은 결절로 기능하였다. 둘째, 조선족의 이주망이 한족보다 발달하였다. 셋째, 국내 조선족 집중거주지의 성장 및 분화 동인으로서 가리봉동(원형/原形), 대림동(확장형), 고등동 및 매산동(재입지형)으로 연결되는 중국 국적인 이주 경로의 발달이 확인되었다. 본 연구는 국적 및 민족 내 집중거주지의 성장 및 분화 과정을 규명한 점에서 의의가 있다.