• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.89-90
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• 2002

Ball reducer (HERB Drive: High Efficient Wave Rolling Ball Drive) with waved grooves has many advantages over other types of reducers for high-reduction ratio, low noise and low energy loss, etc. The mechanism of force transmission is very similar to that of cam and follower in automobile valve train system especially in contact behaviors. In this study, we have investigated the traces of contact between ball and outer ring, and the dynamic contact behaviors of elastohydodynamic lubrication(EHL) with a certain reduction ratio. In order to verify the contact behaviors between ball and outer ring for the critical endurance lift, the contact velocity and load are computed for a cycle. During some intervals of a cycle, the contact velocity reverses its direction very suddenly. It is expected that changing the contact direction causes undesirable endurance performance because EHL film frequently col lapse at the moment of velocity reversal. From the computational investigation in this work, we hope to predict similar contact damages in other machinery due to this kind of contact behaviors, which is very typical in many contact phenomena.

• Toxicological Research
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• 제32권3호
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• pp.259-267
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• 2016

Animal testing was used traditionally in the cosmetics industry to confirm product safety, but has begun to be banned; alternative methods to replace animal experiments are either in development, or are being validated, worldwide. Research data related to test substances are critical for developing novel alternative tests. Moreover, safety information on cosmetic materials has neither been collected in a database nor shared among researchers. Therefore, it is imperative to build and share a database of safety information on toxicological mechanisms and pathways collected through in vivo, in vitro, and in silico methods. We developed the CAMSEC database (named after the research team; the Consortium of Alternative Methods for Safety Evaluation of Cosmetics) to fulfill this purpose. On the same website, our aim is to provide updates on current alternative research methods in Korea. The database will not be used directly to conduct safety evaluations, but researchers or regulatory individuals can use it to facilitate their work in formulating safety evaluations for cosmetic materials. We hope this database will help establish new alternative research methods to conduct efficient safety evaluations of cosmetic materials.

• 복식문화연구
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• 제6권2호
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• pp.77-91
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• 1998

The present study collected and analyzed the Korean's folk-belief related to Koran traditional costume culture which are handed down from ancestor and are known to present Korean society as of 1990's. The purpose of the present study is to understand emotion and the view of Korean people, and to understand the social roles of the costumes in Koran traditional society more deeply and more comprehensively. The study was conducted by document analysis and interview. The results of the study are summerized as follows: Folk-belief related to spinning(gilssam), sericultural industry and weaving are mostly enduced from the hope for god quality of work and acquisition of good skill of weaving. There has been also a belief hat gilssam has a magic power to easy delivery and fecundity. Most Folk-belief of taboo related to clothing constraction proposed to people pay great care while they are sawing. Some ways of management of clothing has been related to the manners of which are associated with the differentiation between high and low level and predominance of men over women that was originated fro m confucianism. Socks(busun) and shoes are also considered to have magic power to prevent from exorcism and demon of ill health. This study suggests that folk-belief give us the wisdom a guideline and lessons for better life, high quality arts and techniques which are handed down from ancestors. Therefore, folk-beliefs having a great value, non-shaped treasures of traditional culture heritage should be collected as many as possible, recorded, and preserved.

• 한국제4기학회지
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• 제16권2호
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• pp.23-31
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• 2002

신생대 제4기 갱신세 동안에 존재하였던 젖먹이짐승(포유류)들은 예전부터 많은 고고학자들의 관심의 대상이 된다. 왜냐하면 유적에서 출퇴되는 이 짐승화석을 통해 그 당시의 자연환경을 밝혀낼 수 있으며, 특히 이들을 잡아먹고 살았던 옛사람들의 생활 모습 - 사냥, 짐승해체, 뼈연모 -을 복원하여 볼 수 있기 때문이다. 그런데 이 젖먹이 짐승들은 오랜 시간에 걸쳐 변화하는 자연 조건에 적응하기 위하여 제각기 다른 특징과 생태요소들을 가지게 된다. 이에 따라 같은 젖먹이짐승이라도 각 뼈대의 부위별로 아주 특별한 구조를 이루는 짐승도 있고 뼈의 수도 현격한 차이를 보이는 것이 있게 된다. 이 글에서는 제4기 갱신세 구석기유적에서 많이 나타나는 여러 젖먹이 짐승의 제각기 다른 뼈대의 구조와 수에 대해서 살펴보기로 한다. 특히 이 변화는 팔과 다리부위에서 많이 나타나고 있으므로 이 부위를 중심으로 고찰해 본다. 이러한 작업을 통해 우리는 구석기시대 옛사람들과 젖먹이짐승의 관계에 대한 좀더 정확한 지식을 얻을 수 있을 것이다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제11권sup2호
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• pp.1-10
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• 2008

When you present a medical scientific paper or give a lecture in English, It is important to visit your presentation room in advance to gain familiarity with the controls and the computer. You can check how to use the mouse or laser pointer and determine where the microphones are. You should meet the Chairman and introduce yourself. You may ask the Chairman any questions you have. I am confident this strategy will work for beginners because they are usually nervous before their presentations. Most Chairmen prepare one or two questions for the presenters to stimulate discussion. Speaking with the Chairman also allows you to determine the type of English that he or she speaks (i.e., French-English, Spanish-English, and British-English). You need to be comfortable with the Chairman's English before the presentation because the Chairman will repeat the questions for you when you do not understand a question from the audience. Although I have given a number of lectures and moderated many scientific sessions and symposiums in English over the past 20 years, it is still difficult and stressful for me to do these in English because English is not my first language. To overcome the problems, I have written down the questions and useful English expressions that I have received during or after my presentation because I found them helpful for my next presentation. I hope the examples will be of great help to you.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.143-149
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• 2002

Ball reducer with waved grooves has many advantages over other reducers for the high-reduction ratios, low noise and low energy loss, etc. The mechanism of force transmission is very similar to that of cam and follower in automobile valve train system especially in the contact geometry. In this study, we have investigated the traces of contact between ball and outer race and the working behaviors with a certain reduction ratio. In order to verify the contact behaviors between ball and outer race, which determines the critical endurance life the contact velocity and load are computed for a cycle. During some period of a cycle, the contact velocity reverses its direction very suddenly, which causes undesirable endurance performance of this machinery. From the computational investigation in this work, we hope to predict similar contact damages in other machinery due to this kind of contact behaviors, which is very common in many contact phenomena.

• 한국자기공명학회논문지
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• 제21권3호
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• pp.102-108
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• 2017

Escherichia coli responds to ever-changing external and internal stresses by rapidly adjusting its physiology for better survival. This adjustment occurs at all levels including metabolites as well as mRNAs and proteins. Although there has been many reports describing E. coli's adaptation to various stresses regarding transcriptomics or proteomics, only a few investigations have been reported regarding this adaptation viewed from metabolites' perspective. We applied four different types of stresses at four different doses as imposed by NaCl, sorbitol, ethanol, and pH to investigate the similarities or differences among the stresses, and which stress causes the largest perturbation of the metabolite composition. We profiled the metabolites under such external stresses by using two-dimensional NMR spectroscopy and identified 39 metabolites including amino acids, sugars, organic acids, and nucleic acids. According to our statistical analysis, the osmotic stress caused by sorbitol differentiated itself from others, while NaCl showed the largest dose dependent metabolic perturbations. We hope this work will form a foundation on which an approach to a successful protein production is systematically provided by a favorable metabolic environment by imposing proper external stresses.

• 한국의상디자인학회지
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• 제13권3호
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• pp.1-14
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• 2011

A dress is commonly designed and worn as a work of art. It is developed through various ways to show the expression of our bodies with functional aspects. Light plays a role in everyday life functionally and aesthetically. We can use the light in many different ways in order to enhance the beauty of the designs. The purpose of this study is to suggest sensible designs with the active expression of light reflection. The designs are especially focused on utilizing light that shows the combination between natural human body's movement and reflection of the light. The use of reflective materials shows the character of movement when it exposes to light. The methods allow to amplify the aesthetic effects of the designs. Reflective materials were used in the resulting design to show the various effects of light by applying the movement which is artistic and aesthetic pleasing aspect for the clothing. The movement is accentuated when the wearer moves, or the air flows through the adding materials on the clothing. In addition, the beads attached to the end of the springs to show the movement of the light. The combination of the spring and the light movement resulted in a dazzling effect. I hope in the future, more studies will be conducted to further use of fiber optics and other innovative ways to use light in fashion.

• 한국과학교육학회지
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• 제14권3호
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• pp.366-378
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• 1994

The titled study has been conducted by collecting questionnaires from 146 secondary school science teachers. The results analysed are as follows. 1. More than half of the science teachers think that they have too much loads on teaching and other works. They hope to teach 15 hours a week or less and also to be waived from extra works not related with teaching. 2. Most of the science teachers think that they are not paid enough salary. And more than half of them feel their economic and social status are below average. 3. Science teachers think that they have good relations with their colleagues but many of them are not much satisfied with the attitudes of students and their parents. 4. Science teachers want better facilities for teaching and for their office. 5. Science teachers feel difficult in teaching laboratory class. They pointed out that it is time-consuming to prepare for experiments and clean up the laboratory and that evaluation of experimental work is not easy. 6. Science teachers appeal that they have difficulties in teaching inquiry skills due to the crowded class and also lack of teaching materials for this purpose.

• 대한가정학회지
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• 제8권1호
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• pp.159-180
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• 1970

Forty-five home account books were randomized by electing "prize for good home manager" in 1967 through all over the country in korea. With this sampling analyzed monthly home expenditure in different item by test of significance, and compared with model of home expenditure and this results. Hope this analysis will help to the house wife for better plan home expenditure and will develope in scientific way of life in home managing. 1. Significance test of home account books in their items and in months indicated that there were significant statistical differences in the total living expenses. In other words, they did not work out a budget, and their home account books were nothing but a record expenses. 2. There was a significant difference in the monthly expenditure for food caused by the preparation of cabbage pickle (kim Jang) in November. This payment in a lump to the cabbage pickle brought about unbalance to home economic. 3. Compared with others, in November and in December we could find a meaningful difference in the monthly expenditure for clothing. 4. It was noted that there were not such comparable significant differences in months as to be mentioned for housing light and heating, education, saving, transportation and communication culture, taxes.