• 한국정밀공학회지
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• 제18권9호
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• pp.89-95
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• 2001

Ceramic tool has to equip with not only high toughness and strength but also low thermal expansion and good thermal conductivity which leads to the high thermal shock resistance. These characteristics make it have longer tool life under thermal stress condition. In this study, commercial Si$_3$N$_4$ceramic cutting tool and home-made SiC based ceramic cutting tools which have different sintering time and chemical composition are tested under various cutting speed and the feed rate increase, the cutting force and the flank wear growth ratio increase, too. The performance of home-made SiC based ceramic cutting tool shows the possibility to be a new ceramic tool.

• 한방안이비인후피부과학회지
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• 제23권2호
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• pp.174-185
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• 2010

Objective : In period of convalescence and aftereffect, facial palsy patients suffer from social and psychological problems, besides experiencing physical inconvenience. So Quality of life is important Evaluation in treatment or facial palsy. Nevertheless the aims of recent study were only trying to explain about objective symptoms. Therefore, Oriental-Western Medicine was performed, effectiveness of treatment were measured in Quality of life. Methods : Acute facial palsy patients who visiting whin 5days completed questionnaire about Quality of life, if he(or she) participated voluntarily. Questionnaire are comprised of general characteristics, Facial Disability Index(FDI), WHOQOL-BREF, VAS and House-Brackmann grade. Questionnaire used two times, the first medical examination and 4weeks later after starting Oriental-Western Medicine. The statistical analysis was performed by GraphPad Prism 4.0. T-test was used to verify effectiveness between the two groups. Results : 1. When we compared the first medical examination with 4weeks later, score of FDI-Physical function and FDI-Social/Well-bieng function increased but they were not valid statistically. 2. When we compared the first medical examination with 4weeks later, in WHOQOL-Brefoverall domain and physical domain, score increased. In WHOQOL-Bref-psychological, Social, Environment domain, score decreased. but, they were not valid statistically. 3. VAS, House-Brackmann grade decreased, but, they were not valid statistically. Conclusion : The number of subjects with facial palsy in our study(N=5) was too small, and the period of study(4 weeks) was short, too. For this reason, our data were not valid statistically. But Facial palsy Patient's Quality of life has risen.

• 산업공학
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• 제15권1호
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• pp.64-72
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• 2002

Broaching machine is widely used for machining inner shaped slots in the work-pieces, and provides vertical motion (usually hydraulically powered) between tool and work-piece. In this study, we modelled the tool life process and investigated economic tool life of broaching machine. Tool life process is divided into wear-process and succeeding failure process. Wear process is defined as machining wear and failure process as 'chipping' occurred by random shock. We modelled wear process as linear regression function for products amounts and assumed failure process as Poisson process. Economic tool life is defined as the number of lots which minimizes average tool related cost per lot and analyzed by using age replacement policy technique. As tool-related cost factors, we consider tool replacement cost, tool maintenance cost and quality costs of products. The results of this study can be applied to analyze life process of general machining tools.

• 유공압시스템학회논문집
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• 제3권3호
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• pp.8-13
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• 2006

It is very important for the manufacturers to predict the life of hydraulic system components according to the results of life tests. Since it takes too much time to test the hydraulic system components until failure, the no-failure test method is applied for the life test of them. If the shape parameter of Weibull distribution, the number of samples, the confidence level, and the assurance life are given, the no-failure test times of hydraulic system components can be calculated by given equation. Here, the procedures to obtain the no-failure test times of the hydraulic system components such as hydraulic motors and pumps, hydraulic cylinders, hydraulic valves, hydraulic accumulators, hydraulic hoses, and hydraulic filters are described briefly.

• 동아시아식생활학회지
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• 제17권4호
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• pp.490-498
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• 2007

The purpose of this study was to investigate the perception of Korean kimchi in Singapore. A questionnaire was given to male 236(43.0%) and female 313(57.0%) college students residing in Singapore. The results are as follows: 86.9% of the participants answered that kimchi is Korean in origin, and 48.7% had eaten kimchi. Also 75.2% of the males and 65.2% of the females had purchased commercial kimchi at restaurants(p<0.05). Regarding the primary reason they purchased commercial kimchi, 62.1% responded 'its taste'(male 58.1%, female 65.0%), also 47.6% stated the package size was 50g(male 44.8%, female 49.7%). Among the kimchi they had experienced, 86.7% had eaten Baechu kimchi, 31.0% Mu kimchi and 30.9% Oi kimchi(males : 82.2% Baechu kimchi, 30.9% Oi kimchi, and 27.4% Mu kimchi, females: 90.0% Baechu kimchi, 33.6% Mu kimchi, and 26.2% Oi kimchi respectively). For their kimchi preference, 67.0% preferred Baechu kimchi, 9.4% Oi kimchi, and 7.1% Mu kimchi(males: 63.4% Baechu kimchi, 12.9% Oi kimchi and 5.4% Mu kimchi, females: 69.5% Baechu kimchi, 8.4% Oi kimchi and 6.9% Mu kimchi, respectively). After having eaten kimchi, 19.3% answer it tasted good, and the primary reason for liking kimchi, 'spicy and hot taste'(51.3%), The main reasons for not liking kimchi were the odor(garlic, ginger, anchovy juice, etc) and too spicy, respectively. Regarding improvements for its expanded consumption 32.0% answered 'not to improve', 18.0% answered 'don't make it too hot', 17.6% answered 'don't make it too salty', and 9.4% answered 'don't make it over-ripe'. For the overall perception of kimchi, the answer with the highest mean(3.95) was 'kimchi is a good side dish with cooked rice', which was significantly different than 'kimchi is delicious'(M=3.14, p<0.05).

• 대한가정학회지
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• 제29권2호
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• pp.135-154
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• 1991

The purposes of this study are: 1) To find out overall family life issues percieved by the middle-classhousewives in their forties. 2) To examine detailed aspects related to middle years crises, leisure activities, children issues, family economy issues, and housing issues. 3) To clarify solutions to, and provide basic data on family issues raised by the middle-class families. The middle-class housewives in their forties living in the Seoul area were the subject of the survey. The sample size analysed in this study was 422. Data were analysed by the frequency, mean, percentile, standard deviation, X2-test, analysis of variance, multiple classification analysis, analysis of multiple regression, and Scheffe-test as a post-hoc analysis. The conclusions are as follows: First, the middle-class housewives tend to give more importance on children issues, especially on academic achievement and career development. Second, family cohesion of middle-class families is comparatively high and intra-familial conflict is low, and middle years crisis of housewives is comparatively low, too. Third, the stability of middle-class families can be found in household economic management patterns. one fourth of the families own stocks and two fifths of the families own real estate except their own dwelling house. Be based on their property income add to their labor income, middle-class families are showed their economic stability, however, intra-class inequality is found, too. Fourth, the great part of middle-class families that possess their own house, tend to be unsatisfied with their housig scale, and a half of the families expect to enlarge their housing scale for more comfortable and convient living.

• 한국과학교육학회지
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• 제12권2호
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• pp.55-65
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• 1992

The purpose of the study is to compare the learning contents of theme acids and bases that are commonly dealed with in elementary, middle and high schools m Korea and to investigate the acid-base-concepts of secondary students. The results of the study were as follows: 1) Many students did not have an interest in the chemistry and they pointed out the necessity of many experiments and practices and its application to the practical life. 2) It is found that most of textbooks used in the elementary school are written to make the students have an interest in the science through the experiments and pratices. However the textbooks used in the secondary school are too theoretically written so that many students are likely to lose the interests in the chemistry. 3) Although students had already learned Arrhenius's acid-base-concept, many students tried to solve the question with Liebig's theory as a acid-base-concept. This misconception might be caused by learning by cramming and teaching too theoretically. Accordingly, it is necessary that the education of science is carried out to make the students have an interest in the science by providing the students with the much more experiments and practices and also applying it to the practical life.

• 복식문화연구
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• 제7권3호
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• pp.93-107
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• 1999

Elderly population of Korea has been significantly increasing, therefore, social and economical influence of the elderly people has been increasing, too. Recently, research regarding elderly people is important because many elderly men take care of their appearance and clothing, and clothing plays an important role in everyday life. The purpose of this study is to investigate the clothing behavior of men aged 55 years and older who were residents of Seoul. The data were collected with a interview and self-administered questionnaire at various places. The importance of various factors on clothing behavior is different. 2. Age has a negative relationship with conformity, but a positive relationship with aesthetics and satisfaction of clothing. Allowance has a positive relationship with all clothing behaviors factors excepts conformity. 3. Life satisfaction has a positive relationship with education and allowance, also, life satisfaction of occupation group is higher than no occupation group is higher than no occupation group. 4. Appearance satisfaction has not a significant relationships with age, but, has a positive relationship with education. 5. There are positive relationships between not only life satisfaction and clothing behavior factors, but also appearance satisfaction and clothing behavior factors except conformity.

• 한국안전학회지
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• 제24권3호
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• pp.19-24
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• 2009

Currently the technique of composite material field is developed day by day. The many kinds industrial facility and life articles are coming to make with the composite material. But still the engineering works field the building and the bridge uses the material which is old era and is making. To here there is a various problem but the biggest problem the theory of the composite material is complicated too and means that the application is been delayed about constructive structure. When the composite material is used widely from constructive field, too with difficult theory in technical expert and easily with the research for the experiment data accumulation is necessary. The tensile and fatigue test of the carbon/epoxy which is a high-class composite material led from the present paper consequently and the change of the intensity coefficient which follows in repeated load researched.

• 대한가정학회지
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• 제31권3호
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• pp.101-112
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• 1993

The purpose of this study is to examine the real life of married women employed in a manufacturing industry by analysis patterns of their time use. Data for 172 married working women were gathered from the use of face-to-face interview method. The results were shown as follows; 1) Married female production workers spend 8 hours 44 minutes a weekday, and 10 hours 39 minutes a Sunday on physiological activities, and on socio-cultural activities 1 hour 50 minutes(weekday), 5 hours 30 minutes (sunday). 10 hours 22 minutes, 2 hours 23 minutes were consumed for the employed time compared to 3 hours 4 minutes, 5 hours 28 minutes for household labor. 2) Married working women's employed labor time is excessively too long while for leisure and house work time is too short, which means the patterns of their time use are very unbalanced type.