http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박종일(Jongil Park),최성욱(Sungwook Choi),김진원(Jinwon Kim) 한국자동차공학회 2012 한국자동차공학회 학술대회 및 전시회 Vol.2012 No.11
엔진 흡기과정에서 실린더 내부 유동특성은 연소특성 및 엔진성능에 많은 영향을 준다. 엔진 효율상승을 위해서는 흡기포트 유동특성을 정확히 예측하여 실린더 내부에 많은 공기가 유입될 수 있는 유동손실이 적은 흡기포트의 설계가 필요하다. 본 연구에서는 엔진 흡기포트 내부의 유동을 파악하기 위해서 상용 삼차원 Navier-Stokes 방정식 코드인 Fluent를 이용하여 전산유체해석을 수행하고 해석의 신뢰성을 검증하기 위하여 유동 실험으로 결과를 비교하였다. 검증된 해석 기법을 이용하여 흡기포트의 주요 형상 변수에 대하여 중심합성법을 이용하여 다양한 경우에 대하여 해석을 수행하고 반응면기법을 이용하여 흡기포트의 유량계수가 최대화되는 최적의 형상을 도출하였다.
[가솔린엔진부문] 스파크플러그 이온프로브를 이용한 직접분사식 가솔린엔진에서의 연소안정성에 관한 연구
박종일(Jongil Park),박기원(Kiwon Park),전광민(Kwangmin Chun) 한국자동차공학회 2000 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
There arc two type of injection mode in direct injection gasoline engine. One is homogeneous mode that is used in high load operation and the other is stratified mode that is used in part load operation. In stratified operation, the AIF in the vicinity of the spark plug is the most important and has significant effects in combustion stability.<br/> In this study, the relation ship between the magnitude of ion probe signals and combustion stability in stratified operation was found by the analysis of ion probe signals using spark plug itself as an ion probe.<br/> In stratified combustion, the magnitude of ion probe signals was higher than that in the homogeneous combustion at the same condition because the pressure and temperature in stratified operation was higher that in homogeneous operation. It could be found that the magnitude of the measured ion probe signals is directly proportional to the combustion stability in stratified operation and the magnitude of ion probe signals was increased as ignition timing was advanced.<br/>
고급차(제네시스), 고성능차(N) 상품성 확보를 위한 엔진 감성 성능 개발
박종일(Jongil Park),최관희(Kwanhee Choi),임현준(Hyunjun Lim),박종국(Jonguk Park),이춘식(Chunsik Lee),김영권(Youngkwon Kim),김명훈(Myunghoon Kim) 한국자동차공학회 2018 한국자동차공학회 부문종합 학술대회 Vol.2018 No.6
Since Hyundai Motor company developed first new alpha engine, HMC has focused to get higher engine performance and better fuel economy. Recently HMC is preparing to enter new high performance , luxury market. To achieve success in that market, powertrain developments are also required to have different approaches. In this study, to satisfy our new customer’s need, two major engine control logic has been developed and applied. One is making after-burn sound and the other is developing launch control with turbocharger pre-charging. The result of two development were impressive in term of customer emotional satisfaction and will be applied to mass production vehicle.
적자회피 및 기업지배구조가 현금유효세율과 GAAP 유효세율의 차이에 미치는 영향
박종일 ( Jongil Park ),이윤정 ( Yun-jeong Lee ) 한국회계학회 2021 회계학연구 Vol.46 No.6
본 연구는 현금유효세율과 GAAP 유효세율의 차이 측정치를 이용하여 적자회피기업이 법인세비용을 낮추어 보고이익을 상향조정 하는지, 또한 지배구조가 우수한 기업은 앞서의 관계에 효율적 통제메커니즘이 작용하는지를 알아보는데 있다. 적자회피기업이 법인 세비용을 이용한 이익조정을 하는지를 알아보기 위하여 본 연구는 현금유효세율에서 GAAP 유효세율을 차감한 차이 값(이하 TD)을 이용하며, 적자회피는 소폭이익을 보고한 경우로 정의하고, 한국기업지배구조원(KCGS)의 기업지배구조 등급과 ESG 자료를 이용하였다. 실증결과는 적자회피와 현금유효세율과 GAAP 유효세율의 차이(TD)는 양(+)의 관계로 나타나 적자회피기업은 그렇지 않은 경우보다 법인세비용을 낮추는 조정을 통해 보고 이익을 상향조정 하였다. 그러나 추가분석에서 이익감소회피와 TD 간에는 유의한 관계를 발견할 수 없었다. 또한 적자회피와 TD 간에 양(+)의 관계는 지배구조가 우수한 기업일 때 약화되는 것으로 나타났다. 그러나 이 결과는 적자회피 구간설정을 넓게 설정한 경우보다 좁게 설정한 경우에서 주로 관찰되었다. 이상을 종합하면, 본 연구는 적자회피기업이 보고이익을 높이는 방법으로 법인세비용을 낮추는 이익조정을 한다는 새로운 증거를 보여주었다는 데 의미가 있다. 또한 앞서의 결과가 우수한 기업지배구조의 조절 효과에 따라 억제됨을 보여준 점도 의의가 있다. This study examines whether firms manage earnings by lowering their tax expenses to avoid reporting losses, and how corporate governance moderates firms’ earnings management through tax expenses. We use tax divergence (hereafter TD), defined as the difference between a firm’s cash effective tax rate (ETR) and GAAP ETR, as a proxy of earnings management through tax expenses, and corporate governance and ESG rating from KCGS as proxies for corporate governance. Loss avoidance is defined as reporting a small positive earnings. We find positive relations between TD and loss avoidance. These relations appear to be weakened by better corporate governance, the effect of which seems to be stronger when loss avoidance is defined using a smaller interval. However, we do not observe significant relations between TD and earnings decrease avoidance in the additional analyses. Our findings suggest that firms may try to avoid reporting losses by reducing tax expenses, and that good corporate governance could help curb earnings management through tax expenses. The results of this study can shed light on the link between loss avoidance and earnings management through tax expenses, as well as the effect of corporate governance on this link. This study contributes to the current earnings management literature by providing novel empirical evidence on the use of a specific method, reduction of tax expenses, to manage earnings.
버추얼 엔진을 활용한 가솔린 엔진의 극한 환경조건 대응 매핑에의 적용 가능성 연구
박종일(Jongil Park),이동규(Dongkyu Lee),김규섭(Kyusup Kim) 한국자동차공학회 2022 한국자동차공학회 학술대회 및 전시회 Vol.2022 No.11
Product development using virtual technology is getting more important in automotive industry. In engine development, virtual methodologies are widely used in emission field such as RDE. However the application for engine calibration supported by virtual model is not commonly used so far despite of its great potential. In this study, engine calibration combining experimental dataset and virtual models were investigated to find out the potential of calibration efficiency and robustness. Two cases calibration against extreme environmental conditions such as very low temperature and high altitude were investigated to apply to mass production projects. One was turbocharger boost control open-loop calibration and the other was ignition correction calibration according to coolant and intake air temperature. In both applications, the dataset from virtual models are successfully linked to existing calibrations methodology. Promising calibration DCM could be achieved in each application. It can be shown from this study that engine calibration by virtual engine at certain surrounding condition is sufficiently beneficial in terms of time and cost. After a number of validation experiences, it can be expected that some calibration can be eventually replaced by virtual methodology and its coverage will grow gradually