http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
황철민(Chulmin Hwang),임영섭(Youngsub Lim) 한국해양공학회 2018 韓國海洋工學會誌 Vol.32 No.5
High-pressure gas injection engines (HPGI) took center stage in LNG carrier propulsion systems after their advent. The HPGI engine system can be easily modified to include a re-liquefaction system by adding several devices, which can significantly increase the economic feasibility of the total system. This paper suggests the optimal operating conditions and capacity for a re-liquefaction system for an LNG carrier, which can minimize increases in the total annualized cost. The installation of a re-liquefaction system can save 0.23 million USD per year when the cost of LNG is 5 USD/Mscf. A sensitivity analysis with different LNG costs showed that the re-liquefaction system is profitable when the LNG cost is higher than 3.5 USD/Mscf.
황철민(Chulmin Hwang),이토히로시(Hiroshi Ito),정영관(Youngguan Jung),김세웅(Sewoong Kim) 한국자동차공학회 2012 한국자동차공학회 학술대회 및 전시회 Vol.2012 No.11
A unitized reversible fuel cell (URFC) which have both of function as water electrolyzer and fuel cell can be a main unit of hydrogen system. The Japan Automobile Research Institute (JARI) standard cell is modified to experiment URFC. The Gas Diffusion Layer (GDL) characteristics of O₂ side are considered for a better performance. The results of experiment show that an influence of Polytetrafluoroethylene (PTFE) on the O2 side GDL has not effect to water electrolyzer mode and has bad effect to fuel cell mode. The bigger Ti-felt fiber diameter has positive effect to the water exhaust and fuel cell mode performance.
정영관(Youngguan Jung),김세웅(Sewoong Kim),황철민(Chulmin Hwang),김두희(Duhee Kim),김병수(Byungsoo Kim) 한국자동차공학회 2008 한국자동차공학회 지부 학술대회 논문집 Vol.2008 No.11
Visualization experiments were carried out on a artificial defect in order to investigate the painting exfoliation mechanism on defects. The behavior of bubbles on the temperature at defects were observed through a microscope and the range of temperature was from 30 to 70degrees. As the results, bubbles made by thermal expansion of the air in defects are a cause of the painting exfoliation. Also, the thin and large expansion of bubbles in liquid paint to be under the hardening paint layer growing from the painting surface form into shape of the painting exfoliation.
고분자전해질막의 노후화에 따른 기계적 특성 변화에 관한 연구
김승환(SEUNGHWAN KIM),어준우(JUNWOO EO),서영진(YOUNGJIN SEO),황철민(CHULMIN HWANG),정영관(YOUNGGUAN JUNG) 한국수소및신에너지학회 2022 한국수소 및 신에너지학회논문집 Vol.33 No.2
Since the various characteristics of the polymer electrolyte membrane are not clearly identified, it is difficult to predict and design applications for various conditions. In this study, as a previous study on the aging of the polymer electrolyte membrane, a study was conducted on the change of mechanical properties according to the aging of the polymer electrolyte membrane. Through the tensile test of Nafion 117, the mechanical properties change due to aging was confirmed. As a result of the tensile test, it was confirmed that the aged Nafion 117 had reduced tensile strength. Through DSC measurement, aged Nafion confirmed that the glass transition temperature and enthalpy change were low, which is thought to be the effect of molecular motion and transition due to the lapse of time. The effect is thought to cause a difference in the amount of change in enthalpy, resulting in a difference in mechanical properties during tension.
어준우(JUNWOO EO),정영관(YOUNGGUAN JUNG),서영진(YOUNGJIN SEO),이동배(DONGBAE LEE),황철민(CHULMIN HWANG),김승환(SEUNGHWAN KIM) 한국수소및신에너지학회 2022 한국수소 및 신에너지학회논문집 Vol.33 No.3
In this study, as one part of the studies on the mechanical properties of the polymer electrolyte membrane, a study was conducted on the change in the mechanical properties due to hydration before and after aging of the polymer electrolyte membrane. The mechanical properties of the polymer electrolyte membrane changes due to hydration were confirmed through tensile tests of hydrated and non-hydrated Nafion 117. As results of this study, non-hydrated membrane showed higher mechanical properties than hydrated thing in the elastic region and some plastic regions. But, it was confirmed that hydrated membrane exhibited higher mechanical properties than non-hydrated thing in the large plastic region. Hydrated membrane has a lower glass transition temperature than non-hydrated thing due to the role of water as a plasticizer. In addition, the number of ion aggregates decreases, but the size increases, and the hydrated Nafion 117 is thought to have different mechanical properties from that of the non-hydrated thing due to the characteristic that the internal attraction is strengthened.