• Journal of Advanced Marine Engineering and Technology
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• v.29 no.2
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• pp.154-160
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• 2005

The result of combustion experiment by using the methanol-gasoline blended fuel showed that the supplying pressure appeared the maximum pressure between equivalent rate 1.1 and 1.2. and the evaporation of the fuel has been known to have been greatly influenced by surrounding temperature and the combustion chamber temperature after being injected from the injector And it is confirmed that the rate of evaporation had been suddenly dropped according to the temperature in the combustion chamber though the injected foe) had been fully evaporated Such tendency has visibly appeared when the zone is leaner. and we recognize that the rich fuel supply is needed in the operation of cold operating.

• Journal of Gifted/Talented Education
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• v.25 no.1
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• pp.37-58
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• 2015

The purpose of this study was to investigate the characteristics of convergence education through the Delphi survey targeting 19 teaching professionals. The Delphi survey was completed three times, drawing key factors and expected outcomes which explain the characteristics of convergence education. The key factors of convergence education were classified as 'educational design', 'teachers' expertise' and 'educational environment'. Educational design focused on the qualitative characteristics of leaner's experience. Teachers' expertise was teacher's active and supportive roles in relationship with fellow teachers and learners. Educational environment was the psychological factors with which various subjects can realize convergence education. The expected outcomes were classified as 'learner's cognitive characteristics', 'leaner's affective characteristics', and 'teacher and educational system'. The expected outcomes of convergence education leads to psychological changes for learners to increase the advanced learning experiences and to pursue values of education itself. Compared to similar concepts, convergence education has some unique characteristics in which many of regular learners in educational settings and various topics are targeted. It also focuses on psychological factors of various subjects and qualitative natures of leaners' learning experience for the advanced learning. Especially, these results have significance in understanding the nature of convergence education, focusing on educational practices through teachers'perspectives.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.325-328
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• 1999

The aim of this paper is to measure the duration of Japanese 'sokuon' [t/k] and 'haneron' [m/n] pronounced by Korean and Japanese. It is revealed in this study that gemination of the Japanese 'sokuon' in Korean pronunciation lasts 1.5 times longer than a single consonant, whereas it lasts 2 times longer in Japanese pronunciation. The difference between Korean and Japanese seems to show the difficulty of perceiving and learning a foreign rhythmic pattern non-existent in the leaner's language. The gemination of [s] phoneme lasts 2 times as long as a single consonant in both Korean and Japanese pronunciation. On average, the duration of Japanese 'sokuon' [t/k/s] is 1.7 times longer than a single consonant in Korean pronunciation, whereas 2 times longer in Japanese pronunciation. The pronunciation of Japanese 'haneruon' by either Korean or Japanese produces a similar result: 1) gemination lasts longer than a single consonant, 2) the duration of the single [m] is longer than that of the single [n]; 3) gemination of [n] is 3 times as long as a single [n], whereas gemination of [m] is 2 times as long as a single [m].

• Korean Institute of Interior Design Journal
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• v.25 no.6
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• pp.15-22
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• 2016

Recent changes in the Korean education policies are promoting the advances in science and technology and cultivating people of convergence talent. STEAM (science, technology, engineering, art and math) educational program is Korean styled convergence program for creative competent human resources. Therefore, Therefore the aim of this study is developing convergence hand-on educational program coping with climate change for elementary school students. For development of the program, we investigated the curriculum of the elementary school about the climate change, and allocated in the creative learning standard frame. Also, we selected themes related the climate change in the curriculum and learning activity. For more effective program to build the convergence competency, we analyzed the program based on creative problem based learning process and 4 core competency(creativity, communication, convergence, caring) elements. In conclusion, the STEAM program needs to develop by school curriculum and leaner's ability. For elementary school students, the STEAM program consists with creative problem based learning process. And the convergence educational program would analyze by the creative PBL process and convergence competency elements. So, this developing program has brought the promotion of the creative convergence competent talented person for the future global environment.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.1-8
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• 2011

In recent years, there has been an interest in early-injection diesel engines as it has the potential of achieving a more homogeneous and leaner mixture close to TDC compared to standard diesel engine. The more homogeneous mixture may result in reduced NOx and soot emissions and higher efficiency in homogeneous charge compression ignition engines. While earlier studies have shown that a reduction in NOx emissions from HCCI engine is possible, there are some significant problems including the control of ignition timing and combustion rate. In order to investigate the effect of EGR and hydrogen enriched gas on combustion characteristics and emissions, an experiments with single cylinder CRDi engine were carried out concerning the formation of various premixed charge, which can achieved by early injection, EGR and hydrogen enriched gas. EGR was not effective to further reduce NOx and PM emissions. It was found that NOx emissions were decreased with an introduction of hydrogen enriched gas and an adequate diesel fuel amount.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.20-25
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• 2006

Recently, there has been an interest in premixed diesel engines as it has the potential of achieving a more homogeneous and leaner mixture close to TDC compared to conventional diesel engines. Early studies are shown that in a HCCI(Homogeneous Charge Compression Ignition) engine, the fuel injection timing and injection angle affects the mixture formations. Thus the purpose of this study was to investigate relationship of combustion and mixture formations according to injection timing and injection angle in a common rail direct injection type HCCI engine using a early injection method called the PCCI(Premixed Charge Compression Ignition). From this study, we found that the fuel. injection timing and injection angle affect the mixture formations and in turn affects combustion in the PCCI engine.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.93-100
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• 2002

For natural gas and LPG fuel, measurements on the concentrations of individual exhaust hydrocarbon species have been made as a function of air-fuel ratio in a 2-liter four-cylinder engine using a gas chromatography. NMHC in addition to the species of HC, other emissions such as CO$_2$, CO and NOx were examined for natural gas and LPG at 1800rpm far two compression ratios (8.6 and 10.6). Fuel conversion efficiencies were also investigated together with emissions to study the effect of engine parameters on the combustion performances in gas engines especially under the lean bum conditions. It was found that CO$_2$ emission decreased with smaller C value of fuel, leaner mixture strength and the higher compression ratio. HC emissions from LPG engine consisted primarily of propane (larger 60%), ethylene and propylene, while main emissions from natural gas were mothane (larger than 60%), ethane, ethylene and propane on the average. The natural gas was proved to give the less ozone formation than LPG fuel. This was accomplished by reducing the emissions of propylene, which has relatively high MIR factor, and propane that originally has large portion of LPG. In addition, natural gas shows a benefit in other emissions (i.e. NMHC,NOx, CO$_2$and CO), SR and BSR values except fuel conversion efficiency.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.3
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• pp.1-9
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• 2006

Recently, there has been an interest in premixed diesel engines as it has the potential of achieving a more homogeneous and leaner mixture close to TDC compared to conventional diesel engines. Because this concept reduced NOx and smoke emissions simultaneously. Early studies are shown that in a HCCI(Homogeneous Charge Compression Ignition) engine, the fuel injection timing and intake air temperature affect the mixture formation. The purpose of this study is to investigate characteristics of combustion and mixture formation according to injection timing and intake air temperature in a common rail direct injection type HCCI engine using an early injection method called the PCCI(Premixed Charge Compression Ignition). From this study, we found that the fuel injection timing and intake air temperature affect the mixture formation and in turn affects combustion in the PCCI engine.

• Journal of Preventive Medicine and Public Health
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• v.12 no.1
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• pp.24-30
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• 1979

This study was conducted to find out the most suitable weight-height index out of the $weight/height^{p}-type$ indices that could be used for the evaluation of nutritional status in an epidemiological survey and for the screening of the obesity. The subjects were chosen randomly, 2,182 males and 719 females from college students and office workers in Seoul districts. The 'best' power-type weight-height index for Korean men and women of all ages from 16 to 59 was found to be $weight/height^{1.54}$ for males and $weight/height^{1.42}$ for females. $Weight/height^2$ (Kaup index), however, was the best suited weight-height index for each age group of both sexes except that relative weight (weight/height) was considered to be desirable to apply for males of teen-aged and of over fifties and for females of over forties of age. Normal ranges of Kaup index values for males and females of each age group were presented in tables 5 and 6. These findings suggest that Koreans are generally leaner than other ethnic groups of the same sex and age.

• The Journal of Korean Association of Computer Education
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• v.8 no.3
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• pp.91-100
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• 2005

On university education, the efforts to improve the curriculum with the leaner based curriculum are proceeding. Those efforts are evaluated as a way to increase the quality of university education, to improve the competitive power of university and to develop learners' ability. I suggested the SSC curriculum and evaluated the educational effect of it in this study, because the current method to select a subject is most simple and non-effective to students. As the result of this study, the achievement of learners involved in the experiment group completing the SSC was higher than that of learners involved in the control group completing the SC.