• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.2
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• pp.72-79
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• 1987

In this paper, an investigation of the property of blended fuel oil, combustion characteristics and engine performance was made, in case blended fuel oil(light oil+heavy oil) was used in a home-made precombustion diesel engine for small-sized fishing boat. The results may be summarized as follows: 1. The specific gravity was linearly increased in accordance with the increase in heavy oil ratio in blended fuel oil, and the relationship between viscosity and temperature was coincided with the formula of Walther-ASTM, and the CCAI, the ignition quality index, was increased nearly as a straight line of the gradient 1.0. 2. The ignition delay was slightly increased below 810 of CCAI(blending ratio to be 60% of heavy oil), but remarkably increased above 810 of CCAI. Therefore, it was considered that the practicable value of CCAI, ignition quality of blended fuel oil, was more than 810. 3. The maximum combustion pressure was increased until blending ratio of heavy oil was raised up to 40%. On the contrary, it came to be decreased at that ratio, with smoke emissions remarkably increasing above 60%. Therefore, it was found in this experiment that the best practicable limit of heavy oil blending ratio was around 50% for saving fuel costs with least smoke emissions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.2
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• pp.26-26
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• 1987

In this paper, an investigation of the property of blended fuel oil, combustion characteristics and engine performance was made, in case blended fuel oil(light oil+heavy oil) was used in a home-made precombustion diesel engine for small-sized fishing boat. The results may be summarized as follows: 1. The specific gravity was linearly increased in accordance with the increase in heavy oil ratio in blended fuel oil, and the relationship between viscosity and temperature was coincided with the formula of Walther-ASTM, and the CCAI, the ignition quality index, was increased nearly as a straight line of the gradient 1.0. 2. The ignition delay was slightly increased below 810 of CCAI(blending ratio to be 60% of heavy oil), but remarkably increased above 810 of CCAI. Therefore, it was considered that the practicable value of CCAI, ignition quality of blended fuel oil, was more than 810. 3. The maximum combustion pressure was increased until blending ratio of heavy oil was raised up to 40%. On the contrary, it came to be decreased at that ratio, with smoke emissions remarkably increasing above 60%. Therefore, it was found in this experiment that the best practicable limit of heavy oil blending ratio was around 50% for saving fuel costs with least smoke emissions.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.113-116
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• 2012

The ignition quality in diesel engines is one of the most important factors influencing their performance. While the ignition quality of distillation fuels is judged with Cetane Number, Cetane Index, and Diesel Index, that of residual fuels blended with distillation fuels is done by using CCAI. Since the 1980s, because of the development in the blending technology and the complexity, it has been difficult to make a judgement on the ignition quality of the fuels with CCAI. Hence, in order to solve the problems, it is ECN that researchers are studying in depth. In this paper, After reviewing the values such as Cetane Number, Cetane Index, Diesel Index, CCAI, and CII, we will introduce ECn and predict the possibility of using it.

• The Journal of Korean society of community based occupational therapy
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• v.10 no.2
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• pp.37-46
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• 2020

Objective : The purpose of this study is to examine the effect of cultural empathy, and personalities on cultural competence among university students of occupational therapy. Methods : One-hundred and fifty-five university students of occupational therapy in Jeollanamdo and Gwangju completed questionnaires consisting of a demographic questionnaire, the Scale of Ethnocultural Empathy(SEE), Big Fie Inventory(BFI), and (CCAI). To determine the relationships among demographic variables, cultural empathy, personalities, and cultural competence, descriptive statistics, Pearson correlation analysis, and regression analysis were analyzed by using SPSS 24.0 for Windows. Results : The results of the study showed the differences in neuroticism and conscientiousness by gender. Also, there were positive correlations between cultural empathy, personality, and cultural competence. Lastly, cultural empathy(β=.357), openness(β=.252), and school year(β=-.148)were significant predictors of cultural competence. Conclusion : The results of this study clarified the relationships among cultural empathy, personality, and cultural competence, and will provide data for the education program to enhance the cultural competence of undergraduates of occupational therapy.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.113-119
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• 2014

Due to the development of the petroleum refining technology and continuously increased demand from markets, a quantity of gasoline and diesel oil produced from a restricted quantity of crude oil has been increasing, and residual fuel to be used at marine diesel engines has been gradually becoming low quality. As a result, it was recently reported that trouble oils which cause abnormal combustion such as knocking with extreme noise and misfire from internal combustion engines were increasing throughout the world. In this study, an author investigated ignitability and combustion quality by using combustion analyzer with constant volume(FCA, Fuel Combustion Analyzer) and middle speed diesel engine about MDO(Marine Diesel Oil), HFO(Heavy Fuel Oil), LCO(Light Cycle Oil) and Blend-HFO which was blended LCO of 1000 liters with HFO of 600 liters. Moreover, for betterment of ignitability and combustion quality of injected fuels, multi-injection experiment was carried out in the diesel engine using Blend-HFO. According to the results of FCA analysis, ignitability and combustion quality was bad in the order of MDO

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.1
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• pp.49-62
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• 2020

Purpose: We aimed to investigate the disease phenotype of Korean pediatric Crohn's disease (CD) patients at diagnosis according to the Paris classification by comparison with patients from the European multicenter 5-years recruitment of children with newly developed IBD (EUROKIDS registry). Methods: Korean children and adolescents who had been newly diagnosed with CD at the age of <18 years during 2013-2016 were included in this multicenter retrospective study. Disease phenotype at diagnosis was classified according to the Paris classification, and compared with the published data from the EUROKIDS study. Results: A total of 255 patients were included. The median diagnosis age was 14.7 years (range, 0.8-17.9 years). No significant difference was observed in male-to-female ratio with EUROKIDS (1.9:1 vs. 1.45:1, p=0.062). The proportion of children aged <10 years was significantly lower in Koreans (7.1% vs. 19.6%, p<0.001). Colonic disease was less prominent (10.0% vs. 27.3%, p<0.001), while upper GI involvement was more prominent in Korean children (59.3% vs. 46.2%, p<0.001). The proportion with perianal fistulizing disease at diagnosis was significantly higher in Korean patients (44.8% vs. 8.2%, p<0.001). A separate analysis of Korean patients revealed that perianal fistulizing disease at diagnosis was positively associated with male sex and body mass index z-score (odds ratio [OR]=2.12, 95% confidence interval [CI]=1.20-3.76, p=0.010; and OR=1.29, 95% CI=1.05-1.58, p=0.015, respectively). Conclusion: Approximately half of pediatric CD patients in Korea present with perianal fistulas and/or abscesses at diagnosis, which is a distinct feature of CD in Korean children and adolescents compared to their European counterparts. An underlying genetic difference between ethnicities may play a role in this expression of different phenotypes in pediatric CD.