http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
VGT와 EGR이 장착된 디젤엔진의 공기순환계 모델에 관한 연구
정동영(Dong-Young Jeong),정재우(Jae-Woo Chung),강정호(Chung-Ho Kang),김남호(Nam-Ho Kim),정진은(Jin-Eun Chung) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
The recent Diesel engine is to install VGT(variable geometry turbocharger) to increase the engine displacement per the power, to reduce the CO2 generation by increasing the BSFC and to minimize the turbo-reg at low speed-load points. And the EGR system is installing for reducing the NOx generation. The VGT and EGR were operated complexly in the engine intake and the exhaust system. Therefore, this study focuses to modify VGT dimensionless model using the flow, efficiency and power parameters which are temperature, pressure and mass flow. and this models were developed to predict the intake and the exhaust state in engine. In case of the Combination with the model which are turbocharger model, intercooler model, exhaust gas model, it is possible to predict intake and exhaust state which are boost temperature, pressure ratio, after intercooler gas temperature, before the turbine pressure and the turbine vane duty using just mass air flow rate within reasonable errors. And in case of introduce the another additional independent parameter, it is possible to increase the prediction accuracy.
유동 에너지 균형을 이용한 EGR 측정 기술 개발에 관한 연구
정동영(Dong-Young Jeong),정재우(Jae-Woo Chung),김남호(Nam-Ho Kim),강정호(Chung-Ho Kang),서영호(Young-Ho Seo),정수진(Soo-Jin Jeong) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
This study focuses the another measurement way of EGR rate without Horiba exhaust analyser. it uses the flow energy balance which is intercooler heat rate plus EGR gas heat rate equals intake manifold. The result of comparison of engine test, the heat transfer should be considered especially Hot HP EGR loop system because EGR gas temperature is higher than cooled HP EGR loop. The correction coefficient considering to heat transfer was fined by using heat rate error for NEDC mode test with 2000cc common rail DME engine. The result of mode test shows the validity of the measurement of EGR rate through the comparison of NOx.
포트폴리오 프로그램의 대안평가 활용에 대한 특수교육 교사의 인식
정소영 ( Dong Young Chung ),정동영 ( So Young Jeong ) 한국특수아동학회 2011 특수아동교육연구 Vol.13 No.3
The purpose of this study is to investigate the special education teachers` perception on the use of portfolio as an alternative assessment. Based on institution of employment and appointed grade, 104 elementary special education teachers were selected into experimental groups and comparative groups with 13 teachers respectively. First, the results showed that there were differences in the impact on special education teacher`s perception of alternative assessment depending on the institution of employment. In particular, the special school teachers` perception of reliability, validity, and efficiency increased significantly compared to that of special class teachers. Secondly, the results indicated that there were differences in the impact on the special education teacher`s perception of alternative assessment depending on the appointed grade level. In particular, the lower grade special class teachers` perception of efficiency and effectiveness significantly increased compared to that of higher grade special class teachers. As seen above, special education teachers improved their perception for alternative assessment by using portfolio assessment. Teachers who work at special education schools perceive portfolio assessment as a useful assessment tool ensured with reliability, validity, and efficiency. Teachers who work in lower grade classes perceive portfolio assessment as a useful assessment tool ensured with efficiency and effectiveness. Therefore, portfolio program should be presented to the students as an alternative assessment method ensured with reliability, validity, efficiency, and effectiveness.
정신지체 특수학교 과학교사의 교수내용지식(PCK)의 구성요소와 구조 탐색
정현우 ( Hyun Woo Jeong ),정동영 ( Dong Young Chung ) 한국특수아동학회 2012 특수아동교육연구 Vol.14 No.2
The purpose of this study, exploring components and structure of Pedagogical Content Knowledge (PCK) of science teachers in special school for students with mental retardation, To achieve this objective, the selected research questions are as follows, First, what is components of pedagogical content knowledge of science teachers in special school for students with mental retardation? Second, what is structure of pedagogical content knowledge of science teachers in special school for students with mental retardation? Six science teachers in special school for students with mental retardation was participated in a one-to-one depth interviews, classroom observation and other documentation, Experiences of preparation, execution and reflection of science teachers analyzed by grounded theory method. The results of this study are as follows. First, Components of Pedagogical Content Knowledge (PCK) of Science Teachers in Special School for Students with Mental Retardation are knowledge of mental retardation students, knowledge of special education, knowledge of teaching environment, knowledge of subject contents, knowledge of curriculum, knowledge of teaching strategies, knowledge of instructional materials, and knowledge of assessment. Second, Structure of Pedagogical Content Knowledge (PCK) of Science Teachers in Special School for Students with Mental Retardation had three core elements of knowledge of mental retardation students, knowledge of special education, knowledge of teaching environment and interacted with each other.
KISE-BAAT(수학)의 신뢰도와 타당도에 관한 연구
박경숙 ( Kyung Sook Park ),정동영 ( Dong Young Chung ),정인숙 ( In Suk Jeong ),송영준 ( Young Jun Song ),김계옥 ( Kye Ok Kim ) 한국특수아동학회 2005 특수아동교육연구 Vol.7 No.3
The purpose of this study is to investigate validity and reliability of KISE-BAAT(Math). KISE-BAAT(Math) test was administered 2,000 students from kindergarten, elementary and middle school level. The results of the study presented that overall alternate-form reliability coefficient is .89 and by subtest it ranges from .36 and .97. Split-half reliability coefficient of each alternate form shows high level of reliability of .98. By grade and subtest it ranges from .39 through .96 for Form A and .28 through .95 for Form B. The overall item response theory reliability coefficient of each alternate form also presents high level of .97 and .99. By grade and subtest it ranges from .69 through .97 for Form A and .77 through .95 for Form B. The overall standard error of measurement of each alternate form presents 2.11 and 2.32 respectively. By grade and subtest it ranges from 0.7 through 1.54 for Form A and .07 through 1.79 for Form B. The overall test-retest reliability coefficient of each alternate form presents .98. By grade and subtest it ranges from .88 through .97 for both forms. Cronbach``s coefficient alpha of each alternate form presents high level of reliability of .99. By grade and subtest it ranges from .25 through .96 for Form A and .37 through .97 for Form B. As for the ontent validity related expert team worked from the stage of setting up standards of achievement, developing test items. The item tryout was administered to select and arrange test items. The criterion -related validity in terms of the relationship with KEDI-Basic Academic Ability Test was examined. The validity coefficient of each alternate form and KEDI-Basic Academic Ability Test showed .70 and .75 respectively. As for intercorrelation coefficient between subtests range from .81 to .95. The results demonstrate that KISE-BAAT(Math) is relatively reliable and valid test instrument.
정진은(Jin-Eun Chung),정동영(Dong-young Jeong),정재우(Jae-Woo Chung),강우(Woo Kang) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
Today, tight and contradictory demands concerning the performance, the exhaust quality and higher milage require the complex system in the engine, such as the combinations of turbochargers. In this engine the control becomes more difficult, Therefore the simple and accurate model for the turbocharger is necessary. This paper deals with the prediction of the compressor performance. The universal curve for flow map and Jenson-Kristensen method for the efficiency map are used. To verify these maps, some measurements were carrying out on the test bench and compared with the results of simulation. As a result of comparison, we can show that the error is inside 5% and it is possible to make 2nd equation compressor performance. Also model using AMESim & IFP engine library is similar to predicted values using universal curve and Jenson-Kristensen method.
문화역사적 활동이론의 관점을 통한 우리나라 특수교육의 체제 분석과 전망
정현우 ( Hyun Woo Jeong ),정동영 ( Dong Young Chung ) 한국특수아동학회 2013 특수아동교육연구 Vol.15 No.1
The purpose of this study was to analyze the systems of special education in the standpoint of cultural-historical activity theory. For this purpose, this study selected the research problems, what is the traditional system of special education when viewing in the standpoint of cultural-historical activity theory? and what is the new system of special education when viewing in the standpoint of cultural-historical activity theory? The findings from this study showed that the system of traditional special education could structualized the second-generation activity theory model, the system of new special education, by the third-generation activity theory model. The external system of traditional special education had a structure that the basic elements, which are the nation and society as the subject of activity, the organ of special education as the mediating artifact of activity, the exceptional children as the object of activity, are interacting with rules, community, the division of labor, and the internal system of traditional special education had a structure that the basic elements, which are the special education teacher as the subject of activity, the special education as mediating artifact of activity, the exceptional children as the object of activity, are interacting with rules, community, the division of labor. Also, the external system of new special education had a structure which produce a new outcome, that is, ``the special education approaching to the regular education`` by interacting of the special education system and the regular education system which are two independent activity systems, and the internal system of new special education appeared to be having a structure which produce a new outcome, that is, ``the special education accomplished by the appropriate arrangement for children`s needs, and education & supporting service offering``.