• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.53-65
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• 2002

This paper studies an economic manufacturing quantity (EMQ) model with two types of failures and planned preventive maintenance of the production facility. One is a type I (major) failure which should be corrected by a failure maintenance and the other is a type H (minor) failure which can be minimally repaired without interrupting the production run. The objective is to determine the lot size and preventive replacement policy minimizing the long-run expected cost per unit time. We consider a control policy with a constant production lot size and preventive maintenance after completing n production runs. It is assumed that both preventive and failure maintenance times are random and the demand arriving during a stock-out period is lost. An expression for the expected cost per unit time is obtained in the general case. A special case is discussed and numerical results are provided.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.178-182
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• 2007

This paper reviews on the LRE health monitoring and emergency protection system to protect test object engine system and engine test facility, in case of various fault occurrence at LRE testing. General composition and major technical consideration of LRE health monitoring system and emergency protection system are reviewed. Moreover, some application of LRE health monitoring/emergency protection system to development test of major LRE component such as turbopump testing, gas generator and combustion chamber test are reviewed.

• Korean Security Journal
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• no.2
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• pp.83-98
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• 1999

The LPG station's explosion at Bucheon city was a major accident which with rare frequency of occurrence but large damage effect. Therefore, to prevent similar accident in the future from LPG chargings stations which located at inner urban area, it needs to identify the damage effects of such facilities by comparing theoretically quantities risks-PHAST. The BLEVE effects from the accident showed similar level in case of heat flux, however, the over pressure level reflected at reduced distance. The structure damage to the nearby area showed comparatively large reduction of concrete strength and shape changes through by heat effect while the overpressure effect was small.

• Management & Information Systems Review
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• v.18
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• pp.223-251
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• 2006

This study examines the factors that have an effect on the satisfaction of student campus life in two college. By the survey questionnaire, three factors selected from 14 questionnaire by factor analysis in the college environmental character. Those factors ware analyzed to estimate the results of this study. And the effect and type of word of mouth communication surveyed by one questionnaire respectively. The major results of this study are as follow; First, the factors that effected on satisfaction of students are the distinction of sex, the division of major field and the distinction of college. But the academic grade factor is not available, Second, the factors of tutors/curriculums and education support service effected on satisfaction of students in campus life, but the factor of education convenience facility is not. Finally, the effect and communication of word of mouth resulted in effectiveness for on satisfaction of students in campus life.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.37-47
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• 1996

The main objectives of this studies are to present the most desirable rice processing complex model system in a given our situations by comparision and analyzing the major factors and, also recommend the future prospect of the rice processing complex in Korea. There are 3 different rice processing complex models in Korea. Those are concrete bin, flat type steel bin and square bin. These systems have a lot of differences and have their own characteristics such as capital requirement, efficiency, storage capacity and quality controls. The major problems of the existing rice processing centers in Korea are high fixed cost and the unbalnced systems. Following is summary to solve this problems: 1. Development of the large scale harvester and high speed continuous dryer. 2. Quality inspective system of bulk grain and large scale temporary storage facilities. 3. Large size readjustment of arable land. 4. Select the convenient location of rice processing center and formulation of well equipment facilities.

• Journal of Digestive Cancer Research
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• v.5 no.1
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• pp.28-31
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• 2017

The number of laparosocpic liver resection performed every years has been increasing. There is a trend than more major hepatectomy and complex liver resection is being reported. However there has been a major obstacles in many centers because open liver resection is still considered as a gold standard and many surgeons are still getting used to the old method of liver resection. To start a new procedure, education and training is essential in order to achieve a good outcome without compromising the safety of the patients. A gradual progression is crucial in order to avoid dreadful complication. The development of the consensus meeting and difficulty score has facility the understanding of safe practice in the development of laparoscopic liver resection. In a long run, development of registry system will improve transparency and safety of this operation.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.494-500
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• 2007

The purpose of this study was to examine the levels of satisfaction, and awareness, as well as evaluations of internship programs between major and non-major students in food and nutrition. The survey was conducted via questionnaire to 80 major and 113 non-major students in food and nutrition who had finished an internship. For the primary internship facilities, the proportions were 51.3% in foodservice for the major group and 57.4% in business & industry for the non-major group. For the internship period, the proportions were 71.2% for under 2 weeks in the major group, and 42.9% for $2{\sim}4$ weeks in the non-major group(p<0.001). The proportions of students who were provided orientation from a professor(p<0.001), and visiting guidance by a professor(p<0.001), were 40.5% and 35.4%, respectively, in the major group and 73.4% and 82.1 %, respectively, in the non-major group. The proportions answering that the internship was a necessity were 95.0% in the major group and 75.2% in the non-major group(p<0.001). The major group had significantly higher satisfaction scores for location of the internship facility, internship period, and connection between education and practice as compared to the non-major group. However, the satisfaction score for professor's guidance during the internship was significantly lower in the major group than the other group. The evaluation score for 'I did my best when doing my work' was significantly higher in the major group than the non-major group. The major group had significantly higher awareness scores for the internship's degree of assistance in improving skills, making use of knowledge, and adapting to the field, as compared to non-major group. In conclusion, students majoring in food and nutrition faithfully participated in their internship programs, with higher degrees of satisfaction and awareness, and higher evaluations. However, more effective internship program with intensified and developed guidance by professor are needed.

• Journal of Environmental Impact Assessment
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• v.19 no.1
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• pp.29-38
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• 2010

At recent the number of livestock is increased and the size of farm has changed to large facilities in Korea. So the livestock facilities have become one of major sources of odor emission. The purpose of this study is to analyze the concentration and assessment of odor unit from livestock facilities for cow, dairy, swine and poultry. The eleven odor pollutants such as $H_2S$, ($CH_3$)SH, $(CH_3)_2S$, $(CH_3)_2S_2$, $CH_3N$, $NH_3$, $(CH_3)_2N$, $(CH_3)_3N$, butyric acid, valeric acid and isovaleric acid, measured for assessment of the odor concentrations from livestock facility. As the results, it is found that the major matters of odor from livestock facilities were $NH_3$ and $H_2S$. The highest concentration of $NH_3$ is measured as 15 ppm at henhouse and $H_2S$ is measured as 858 ppb at penpig facilities. In the comparison of the average odor unit from livestocks, it is found that the highest odor unit was from swine and the lowest odor unit was from cow facility. So odor unit from swine facilities was 12 to 30 times higher than the odor unit from cow facilities.

• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.46-51
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• 2000

It is required that fuel gas accidents should be managed carefully along with the increase of fuel gas consumption. Factors to cause accidents were investigated through a systematic analysis of gas accidents during recent 4 years, which could be applied to prepare countermeasures to reduce gas accidents. The thawing season is found to be weak to gas accidents, showing a slightly higher rate of accident occurring than average. During this term although the number of LPG accident is similar to that of yearly average, countermeasures are required for LPG facilities since the portion of accident is large; in detail, user's carelessness, defective facility, or instrument failure are major causes. The number of city gas accident facility is larger than that of yearly average; particularly, defective facilities, third-party work, and appliance failure are major causes. As a result, countermeasures have been suggested for the accident of large portion or above yearly average.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.223-231
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• 2005

A quantitative risk assessment tool was used to provide estimates of the probability that foot-and-mouth (FMD) virus-contaminated, smuggled animal products are fed to susceptible swine in Korea. Sensitivity analyses were conducted to attempt to distinguish between parameter uncertainty and variability, using different assumptions on the effect of cooking at home, the effect of the fresh meat, and the effect of heat treatment at garbage processing facility. The median risk estimate was about 20.1% with a mean value of 27.4%. In a scenario regarding all beef and pork were considered as fresh meat the estimated median risk was 3.4%. The risk was greatly dependent on the survival parameters of the FMD virus during the cooking or heat treatment at garbage processing facility. Uncertainty about the proportion of garbage that is likely contaminated with FMD had a major positive influence on the risk, whereas conversion rate representing the size of a load had a major negative effect. This model was very useful in assessing the risk explored. However, the model also requires enhancements, such as the availability of more accurate data to verify the various assumptions considered such as FMD prevalence in a specific country, proportion of garbage which is recycled as feed, proportion of food discarded as garbage. Other factors including the effect of selection of animals for slaughter, ante- and post-mortem inspection, the domestic distribution of the smuggled products, and susceptible animals other than pigs, are need to be taken into account in the future model development.