http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김광대(Kwangdae Kim),서병준(Byungjun Seo),오민석(Minsuck Oh),김치원(Chiwon Kim) 한국자동차공학회 2005 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-
With the rapid development of modern industrialization, human begins have been exposed to environmental pollution and have been paying special attention to preventing it. Recently, in the representative research of reducing NOx as well as improving Compression Ignition Engine performance, it is being regarded as important to correctly understand the high pressure spray to determine the initial conditions of combustion characteristics and the ultimate interior design of a combustion chamber. For the CI engine, optimizing the ultimate fuel injection timing according to the operating conditions is of great importance, because the fuel injection timing has considerable influence on the combustion characteristic and emission formation. The purpose of this research is to find thc optimal combustion characteristics and reduce the exhaust emission based on the wall impingement with changing by the important combustion-related factors through the numerical analysis methods.
체외수정시술의 결과를 예측할 수 있는 인자로서 난구세포의 활용에 관한 연구
김광대,김기형,나용진,이규섭,Kim, Kwang-Dae,Kim, Ki-Hyung,Na, Yong-Jin,Lee, Kyu-Sup 대한생식의학회 1999 Clinical and Experimental Reproductive Medicine Vol.26 No.3
Objective: To establish the evaluation system of the quality of oocytes on the basis of the incidence of cumulus cells apoptosis, to investigate the relationships beween the incidence of cumulus cells and the outcomes of IVF-ET. Method: Thirth-four cycles undergoing controlled ovarian hyperstimulation for IVF-ET with tubal infertility (23 cycles) or unexplained infertility (11 cycles) were included in this study. Cumulus cell masses surrounding mature oocyte and co-culture of embryos with autologous cumulus cells during IVF-ET process. The incidence of apoptosis in cumulus cells was assessed by apoptosis detection kit fluorescein. The effect of co-culture using cumulus cells and the incidence of cumulus cells apoptosis. Results: The results were as follows: 1. The incidence of apoptosis in cumulus cells markedly increased in patients aged 40 or over, while the fertilization rate was greatly decreased in those age group. 2. Apoptosis in cumulus cells was found in both the fertilized oocytes and unfertilized oocytes, but the incidence of apoptosis was higher in unfertilized oocytes. 3. There is no clear correlation between apoptosis in cumulus cells and the number of oocytes retrieved. However, the incidence of apoptosis was increased when the number of oocytes retrieved was 5 and fewer in comparison with $6{\sim}10$. 4. Embryo grade was significantly affected by the incidence of apoptosis in cumulus cells. 5. Pregnancy rate of IVF-ET per cycle was 29.4%, and the pregnant group had the higher fertilization rate and a significantly lower incidence of apoptosis in cumulus cells compared with the nonpregnant group. 6. When cumulus cells were used as helper cells in the co-culture of the embryo, in vitro activity of cumulus cells based on morphological change and proliferation did not influence the quality of embryo, but was closely associated with the implantation rate and pregnancy rate, which was enhanced when morphological changes and proliferation of cumulus cells was more active. 7. This difference in the outcome of IVF-ET according to in vitro activity of cumulus cells used for co-cultue was not associated with the incidence of apoptosis in cumulus cells; but rather had likely relations with the different secretion pattern of protein, which may be an embryo trophic factor by cumulus cells. Conclusion: These results suggest that the incidence of apoptosis in cumulus cells can be used in predicting oocyte qualities and the outcomes of IVF-ET. And the effect of co-culture largely depends on the in vitro activity of cumulus cells as well.
김광대(Kwangdac Kim),서병준(Byungjun Seo),오민석(Minsuck Oh),김치원(Cbiwon Kim),정용관(Yonggoan Jung),이병호(Byungho Lee) 한국자동차공학회 2005 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-
Recently, in the representative research of reducing exhaust emission as well as improving Compression Ignition Engine performance, it is being regarded as important to correctly understand the high pressure spray to determine the initial conditions of combustion characteristics and the ultimate interior design of a combustion chamber. For the CI engine, optimizing the ultimate fuel injection timing and angle according to the operating conditions is of great importance, because the fuel injection timing angle has considerable influence on the combustion characteristic and emission formation. The purpose of this research is to find the optimal combustion characteristics and reduce the exhaust emission based on the wall impingement with changing by the important combustion-related factors through the numerical analysis methods.
압축점화기관에 CH₃(CH₂)₂CH₂OH 연료분사 시 연소특성에 관한 연구
김치원(Chi-won Kim),안희찬(Hee-chan An),김판호(Pan-ho Kim),김광대(Kwang-dae Kim),윤정민(Jeong-min Yoon) 한국자동차공학회 2002 한국자동차공학회 지부 학술대회 논문집 Vol.2002 No.3
Recently, compression ignition engines using diesel oil, because of better fuel economic, are rapidly gaining a large share of the market for passenger car application in addition to their more traditional use for heavy duty trucks and marine engines, but the problem of exhaust emission, particularly NOx and PM from CI engine has been focussed mainly in the view point of environment.<br/> In this experimental study, as the alternative fuel, n-Butyl alcohol and methanol fuel in tested with some blend fuels with diesel oil. The compression ignited type, diesel engines in equipped without turbor charger(NA), in intake manifold system for analyzing engine performance, combustion characteristics.
稀薄燃燒 엔진에서 전자제어 히스테리시스 현상에 관한 實驗的 研究
김응채(Eung-Chae Kim),김광대(Kwang-Dae Kim),김치원(Chi-Won Kim) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
In this study, it is experimented and analyzed the swirl mode control method to overcome the hysteresis phenomenon between normal and lean bum mixture range at engine operation. The experimental engine used in test has been modified Lean Bum 1.5DOHC S.I. engine, developed EMS(Engine Management System) for engine control, and connected the controller circuit of hardware for mode. That is, under full operating range, notified 800 ± 100 rpm of idling operating speed to be stable engine test, and lower exhaust emissions from Look up table set up mapping values of controlling fuel injection and optimum ignition timing, equivalence ratio, and idling speed.