자동차정비직무를 위한 국가직무능력표준(NCS) 개발

지명석,노희규,한영민,Jie, Myoung-Seok,Noh, Hi-Kui,Han, Young-Min 대한기계학회 2014 대한기계학회 논문집. Transactions of the KSME. C, 산업기술과 혁신 Vol.2 No.2

자동차정비직무의 "일과 학습의 연계"를 위해 현장에서 필요한 직무수행능력을 기준으로 자동 차정비 분야에 대한 교육훈련과 자격기준으로 활용할 수 있도록 자동차정비 현장전문가들이 국가직무 능력표준(NCS: National Competency Standards)을 개발하였다. 본 연구를 통하여 자동차정비직무의 국가 직무능력표준 개발영역과 직무체계를 수립하였고 직무능력단위별 수행준거, 지식, 기술, 태도 및 평가방법을 제시하였다. 또한 자동차정비직무의 능력단위별 직업기초능력의 영역별 수준을 제시하였으며 자격기준안을 제시하여 교육과 평가의 기준을 마련하였다. Automotive field specialist developed National Competency Standards for Automotive Maintenance to apply for the education and evaluation of automotive maintenance. National Competency Standards scope and system for Automotive Maintenance has been developed and provided Performance Criterion, knowledge, skill, attitude, and evaluation methods for each item. Also it has provided vocational basic knowledge level and qualification frame for automotive maintenance.

예연소실을 갖는 점화플러그의 공연비 변화에 따른 연소 및 화염전파 특성

지명석(Myoung-Seok Jie),정인태(In-Tae Johng),유성연(Seong-Yeon Yoo) 대한기계학회 2008 大韓機械學會論文集B Vol.32 No.2

The new concept spark plug was developed which has pre-ignition chamber and flame hole in the lower end. Fresh mixture gas can be introduced through the flame hole without any fuel supply system. The effects of new spark plug on the combustion and flame propagation for different air fuel ratio was investigated for varying hole sizes and hole numbers. This spark plug was tested in a single cylinder engine dynamometer to measure the fuel consumption rate, emission gases, and MBT timing for different air fuel ratio. Also combustion pressure and average flame propagation speed were measured by use of piezo electric pressure sensor and cylinder head gasket ionization probe. The spark plug with pre-ignition chamber induces fast bum, low HC and low fuel consumption rate compared to conventional spark plug in lean air fuel ratio. As the air fuel ratio was increased, mass burnt duration was increased. Spark plug with pre-ignition chamber with 5 hole was more effective in combustion performance than spark plug with pre-ignition chamber with 1 hole.

예연소실 점화플러그의 화염가시화와 화염전파특성

지명석(Myoung Seok Jie),유성연(Seong Yeon Yoo),정인태(In Tae Johng) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

New concept spark plug was developed to study its influence on the combustion characteristics of SI engine. It has pre-ignition chamber at the lower end of spark plug and flame hole, in which fresh mixture gas can be put in through the flame hole without any fuel supply system. This spark plug was tested in a single cylinder engine dynamometer for different air fuel ratio to measure the fuel consumption rate, emission gases, and MET timing. And constant volume combustion chamber was made to understand flame characteristics of spark plug. New spark plug induced fast burn compared to the conventional spark plug and its effects were increased in lean air fuel ratio. Pre-ignition chamber spark plug with 5 holes which had adjusted size was more stable and effective in combustion performance than pre-ignition chamber spark plug with 1 hole. And its effects showed larger differences in lean air fuel ratio than stoichiometric condition. Flame kernel and flame growth process of conventional spark plug and pre-ignition chamber spark plug studied by flame visualization of schlieren method.

예 연소실을 갖는 점화플러그의 연소 특성에 관한 연구

지명석(Myoung-Seok Jie),유성연(Seong-Yeon Yoo),박준택(Jun-Tack Park) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11

New concept spark plug was developed to study its influence on the combustion characteristics of SI engine. It has pre-ignition chamber in the lower end of spark plug and flame hole. Fresh mixture gas can be got in pre-ignition chamber of spark plug without any fuel supply system. This spark plug was tested to a commercial engine. Fuel consumption rate, emission gas and MBT timing were measured in the engine dynamometer varying the flame hole number, hole position, hole size of the pre-ignition chamber of the spark plug. New concept spark plug induces fast burn in combustion than comparing with the conventional spark plug. MBT timing was retarded about 3~5˚ crank angle. The flame hole number, hole direction and volume of pre-ignition chamber were found to influence emission gases.

SI 엔진의 텀불 유동과 화염전파

지명석(Myoung-Seok Jie) 한국산업융합학회 1999 한국산업융합학회 논문집 Vol.2 No.2

In this study, single cylinder engines with different tumble ratio were made to find out in-cylinder fluid motion and flame propagation. Tumble ratio derived from the steady state flow rig test. Flame propagation speed was obtained using cylinder head gasket ionization probe and the piston ionization probe. And the combustion pressure in cylinder was measured to analyze the combustion characteristics. In case of high tumble engine, BSFC and BSHC were decreased and BSNOx was increased at part load test. Also BMEP and combustion peak pressure was increased at full load test. Tumble flow motion had an great effects on initial burning period rather than main burning period in part load test.<br/> <br/>

미라클 탑 엔진 오일이 엔진 성능에 미치는 영향 분석

지명석(Myoung-Seok Jie) 한국산업융합학회 2002 한국산업융합학회 논문집 Vol.5 No.2

In this study, general engine oil and the Miracle top engine oil of Dongjin chemistry company were tested to find the effects to the SI engine performance. Roller dynamometer used to find maximum power, fuel consumption rate and the emission. Maximum power was measured higher when the Miracle top engine oil was used in the vehicle. By use of the Miracle top engine oil, fuel consumption rate and emission was measured lower and compression pressure was higher compared use of general engine oil. Also the Miracle top engine oil was found to decrease the engine noise at the low HPM. And after 1,500km drive at the same condition, the dust in the oil pan and oil filter was measured less when the Miracle top engine oil used compared than general engine oil used.<br/>

광섬유 장착 점화플러그와 이온 프로브에의한 화염전파측정

지명석(Myoung-Seok Jie),이시훈(Si-Hun Lee),이경환(Kyung-Hwan Lee) 한국자동차공학회 1994 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1994 No.11_1

The optimized fuel injection timing during intake stroke is very important to extend the lean misfire limit of lean bum system. The effects of fuel injection timing on the combustion characteristics were investigated with a single cylinder 4 valve DOHC engine with lean bum system. The fiber optic spark plug and printed circuit board head gasket ionization probe were applied to obtain the flame kernel growth rate and convection velocity in the vicinity of spark plug and flame propagation characteristics in the end zone of combustion chamber. The pressure in the combustion chamber was also measured to understand the combustion characteristics such as initial burn duration and main bum period and compared with the flame propagation.<br/> It was found that in case of 1 valve open, the flame propagation measured by the fiber optic spark plug was consistent with the expected charge motion. The optimized fuel injection timing which has more extended lean misfire limit also showed maximum flame kernel growth rate.<br/>

예연소실 점화플러그의 화염가시화와 화염전파특성

지명석(Myoung Seok Jie),정인태(In Tae Johng) 한국가시화정보학회 2016 한국가시화정보학회지 Vol.14 No.3

New concept spark plug was developed to study its influence on the combustion characteristics of SI engine. It has pre-ignition chamber at the lower end of spark plug and flame hole, in which fresh mixture gas can be put in through the flame hole without any fuel supply system. This spark plug was tested in a single cylinder engine dynamometer for different air fuel ratio to measure the fuel consumption rate, emission gases, and MBT timing. And constant volume combustion chamber was made to understand flame characteristics of spark plug. New spark plug induced fast burn compared to the conventional spark plug and its effects were increased in lean air fuel ratio. Pre-ignition chamber spark plug with 5 holes which had adjusted size was more stable and effective in combustion performance than pre-ignition chamber spark plug with 1 hole. And its effects showed larger differences in lean air fuel ratio than stoichiometric condition. Flame kernel and flame growth process of conventional spark plug and pre-ignition chamber spark plug studied by flame visualization of schlieren method.

COVID-19 상황에서 원격수업에 대한 기술융합 공업계 대학의 교수자와 학습자 인식 고찰

문병구,지명석,신준용,Moon, Byung-Koo,Jie, Myoung-Seok,Shin, Jun-Yong 중소기업융합학회 2021 융합정보논문지 Vol.11 No.10

본 연구는 코로나19로 인한 대학의 원격수업이 장기화하고 교수자와 학습자의 어려움이 계속됨에 따라, 여러 기술이 결합 된 기술융합 부문 공업계 대학 교수자와 학습자의 인식 파악을 통하여 개선 방안을 도출하고자 하였다. 이를 위해 2020학년도 2학기 종료 시기에 자동차 계열 교수와 학생들을 대상으로 온라인 설문조사를 실시하였다. 설문조사 분석 결과, 교수와 학생은 온라인 수업의 장점 측면에 대해서는 시공간의 자유로움, 반복 학습 가능, 재활용 등 유사한 인식을 하는 것으로 나타났다. 애로사항 측면에서는 학생은 현장감 부족으로 학습몰입 떨어짐을, 교수와 학생 모두는 상호작용의 어려움을 상대적으로 크게 느끼는 것으로 나타났다. 본 연구는 기복이 있는 코로나 상황과 코로나 이후 공업계 대학의 온라인 교육에 대하여 대학 정책지원에 관한 제언과 기본자료를 마련한다는 의의가 있다. This study tried to derive improvement measures by identifying the perceptions of industrial college instructors and learners in the technology convergence sector, where various technologies are combined, as distance education at colleges are prolonged due to COVID-19 and difficulties for instructors and learners continue. To this end, an online survey was conducted on automobile professors and students at the end of the second semester of 2020. As a result of the survey analysis, it was found that professors and students had similar perceptions about the advantages of online classes, such as freedom of time and space, repeatable learning, and recycling. In terms of difficulties, it was found that students felt a decrease in learning immersion due to a lack of sense of presence, and both professors and students felt the difficulty of interaction relatively large. This study is meaningful in that it prepares suggestions and basic data on college policy support for online education at industrial colleges during and after COVID-19.

Fluidic Valve의 유동 특성에 관한 연구

유성연(Seong-Yeon Yoo),지명석(Myoung-Seok Jie),김기형(Ki-Hyung Kim),김만웅(Man-Woong Kim) 한국유체기계학회 2001 유체기계 연구개발 발표회 논문집 Vol.- No.-

Fluidic valve is adopted in APR1400 to control passively the flow rate of cooling water from the safety injection tank. It is necessary to establish independent evaluation guideline for the flow characteristics of fluidic valve in order to secure safety. Three dimensional numerical model for fluidic valve is developed and numerical results are compared with experimental data obtained at KAERI in order to verify numerical simulation. Also influence of the grid number and the turbulence model were investigated. In addition, variation of flow rate is investigated at various elapsed times after valve operating, and flow characteristics are analyzed at low and high flow rate conditions, respectively.