http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
상온 반복압축 후 가압소결에 의한 알루미나 분말의 소결특성 -치밀화와 결정립 성장 및 파괴인성-
손건석,서정,백성기,김기태,Son, G.S.,Suh, J.,Baik, S.K.,Kim, K.T. 한국세라믹학회 1993 한국세라믹학회지 Vol.30 No.1
Densification of alumina powder, grain size and fracture toughness of sintered body by hot pressing after cold compaction were investigated and compared to traditional hot pressing process (without cold cyclic compaction). To achieve a higher densification and to reduce the hot pressing time, hot pressing after cold cyclic compaction was more efficient compared to traditional hot pressing. This phenomenon resulted from the increment of packing densityby the acceleration fo rearrangement of powders under cold cyclic compaction. The grain size of sintered body was only dependent on relative density, and densification during hot pressing was governed by thelattice diffusion. Comprisons of grain size, densification mechanism and fracture toughness resulted from hot pressing after/without cold cyclic compaction showed that a low cyclic pressure may not effect on the fragmentation of alumina powders.
알루미나 분말 기지혼합체의 상온 반복압축 후 가압소결 -상온 반복압축 효과-
손건석,서정,박병학,김기태,Son, G.S.,Suh, J.,Park, B.H.,Kim, K.T. 한국세라믹학회 1993 한국세라믹학회지 Vol.30 No.2
Hot pressing after cold cyclic compaction of Al2O3 powder mixtures containing SiC whiskers or Al2O3 short fibers is studied with emphasis on the effects of cold cyclic compaction. The green density of the mixtures increases as the cycle number increases and the cyclic pressure becomes higher. The higher green density is also obtained by cold cyclic compaction with the lower pressrue than a single stroke cold compaction. To achieve a higher densification during hot pressing, cold cyclic compaction before hot pressing is more efficient compared to the conventional hot pressing process (without cold cyclic compaction). Moreover, a low cyclic pressure did not affect on toughening mechanism by whisker reinforcement.
손건석(G.S.Son),최병철(B.C.Choi),이귀영(K.Y.Lee) 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.6_1
To find out optimum operating conditions for a EHC system, space velocity, coexistence gases and O₂ concentration effects were examined. The best HC and CO conversion efficiency was obtained in the range of 13000 - 14000 1/h space velocity. It was found that HC conversion at cold-start of the engine was improved by the coexistence of CO. While, O₂ concentration and coexistence of NOx did not affect the conversion efficiency of HC.<br/>
2차공기 공급을 이용한 배기 저감 기술의 실용성에 관한 연구 Ⅱ
손건석(G.S.Son),고성혁(S.H.Ko),이귀영(K.Y.Lee),최의락(E.R.Choi),김영웅(Y.W.Kim) 한국자동차공학회 1998 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1998 No.11_1
One of the promising technologies for LEV program secondary air injection system has been studied widely. In this paper feasibility test of secondary air injection system for LEV program and a comparison of its efficiency with that of a passive A/F control system were done using the FTP75 test on a 2.0 DOHC A/T vehicle. The engine out and tai lpipe emissions were recorded by the second with the temperatures of exhaust gas and the warm up converter. The temperatures were measured at manifold, inlet and the center of the warm up converter. The vehicle had a 0.67L Pd-only warm up converter and a 1.8L underbody converter which were 50k aged on MAD for the aftertreatment system and a ECU of LEV level. The ULEV regulation was sat isfied through a secondary air inject ion system. But the ULEV regulation was also satisfied with the lean A/F control during the first 40 sec after cold start. This study showed the lean A/F control strategy could be one of the potent ial technologies to meet LEV/ULEV regulations without any other additional active system.<br/>
손건석(G. S. Son),이지연(G. Y. Lee),이귀영(K. Y. Lee),최병철(B. C. Choi) 한국자동차공학회 1996 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1996 No.6_2
Quick aging of catalysts has done wi th, IAE AGING MODE suggested by lAE. To estimate the<br/> effects of number of aging cycle. temperature and H₂O. characteristics of surfaces. mechanical properties and Weibull Modulus were estimated. Also, the conversion efficiency of aged catalysts was evaluated with model gas bench test. The area of surface and pore volume were decreased according to the number of aging cycle. The precious metal which is well dispersed in fresh state was sintered and agglomerated with aging. The mechanisms ui deactivation and sintering of catalysts are discussed on the basis of mechanical tests. The conversion efficiency was decreased wi th the repeats of aging. Especially. the existence of H₂O in supply gas had a main role in catalyst deactivation with high temperature.<br/>
Close-Coupled Catalyst(CCC)의 최적운전조건에 관한 연구
손건석(G.S. Son),김대중(D.J. Kim),이용래(Y.R. Lee),이귀영(K.Y. Lee),최병철(B.C. Choi) 한국자동차공학회 1996 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1996 No.6_2
In this study. the vehicle test and analytic investigation of the 3 kinds of volume of CCC have been carried out. To optimize' the size and location of CCC in a aftertreatment<br/> system. it is necessary to know the characteristics of CCC like as a adsorption efficiency. a capacity of energy storage. etc. To understand these characteristics, the resul ts of FTP75 vehicle test was used. In the mode test. the temperature profiles were recorded with emission results. And the energy balance of CCC was studied with the data.<br/> As a result. the optimum volume and position for CCC in a car was suggested.<br/>