• Tribology and Lubricants
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• 제25권5호
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• pp.311-317
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• 2009

To satisfy the more severe emission regulation and the demand of higher fuel economy in near future, the combustion pressure and power output of engines is going to be higher. In order to get the reduction of engine emission and the higher power, it is needed the reduction of the tension and width of ring pack. The lower tension ring and the thinner width ring can bring not only the friction reduction between the ring and liner during engine running, but also the adjustment of the blow-by gas and oil consumption by changing in the pressure in the crevice volume and the axial motion of rings togethe with the adjustment of the inter-ring crevice volumes. In this study, by using a developed basic computer proglram that predicts the blow-by gas and oil consumption of engines, it is to be examined how satisfying the level of the blow-by gas and oil consumption as being installed the piston ring pack with thinner width ring and lower tension ring.

• 한국산업보건학회지
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• 제16권4호
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• pp.314-323
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• 2006

This study was conducted to identify ingredients of thinners and to confirm reliability of material safety data sheets (MSDS) of thinners for public and workers' health. The 41 thinner products were collected from paint shops located in Busan and Gyeongnam province. The 12 thinner products among them were identified using product MSDS. GC-MSD was used to analyze 41 kinds of thinners qualitatively and quantitatively. The 12 products MSDS were compared with thinner's component through qualitative analysis to confirm MSDS. Chemical ingredients, such as Benzene, Toluene, and Xylene etc., of thinners were analysed in quantity. The 41 thinner products contained 17 disclosed specific, trade name, or generically described chemical solvent ingredients. These 17 ingredients came under 6 classes: alcohols, aromatic hydrocarbons, esters, glycol ethers, ketones, and mixtures. These 17 ingredients were important in the view of industrial hygiene and had occupational exposure limit in the ambient, such as toluene, xylene, acetone, nonane, EGEE, heptane, cumene, MIBK, indene, tri-methyl benzene, etc, were found in 41 kinds of thinners. Aromatic hydrocarbons were the most identified ingredient in thinners. Especially, the benzene, which induces leukemia, was found in 4 kinds of thinners. The content rates of benzene in thinners were 0.25~1.18%. The benzene in enamel thinner, which were 0.39~0.72%, was highest from chemical classification. The contents of toluene, which was found from 27 kinds of thinners, were 5.35~64.16%, which were highest in sobu thinner as 58.80%. Xylene was found from 22 kinds of thinners and contents of xylene were 4.61~72.42%. Acrylic thinner's contents of xylene were 12.06~51.05%, which was most high. It was found that contents of benzene were increased and frequency of detection was decreased through comparison with other study. The MSDS possession rate of paint shops was low as 29.27%. So it did not provide information with public or workers. Mean of agreement rate between MSDS and components of thinners through qualitative analysis was 42.01% and it has wide range from 8.3% to 75%. There are many deficiencies in MSDS about component of thinners. In some case of sample, expecially, despite containing benzene, information was not written it on MSDS.

• 한국수소및신에너지학회논문집
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• 제5권2호
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• pp.59-63
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• 1994

Thermally evaporated Pd films on substrate were hydrogenated upto 1 bar of hydrogen gas at room temperature. Thickness dependence on hydrogenation on Pd film is examined in the thickness range between $60{\AA}$ and $800{\AA}$. Hydrogenation kinetics of thinner films(thinner than $500{\AA}$) and that of thicker films are different. Thin film(thickness < $200{\AA}$, substrate temp. = RT) showed recrystallization due to hydrogen induced heat. Hydrogen was absorbed by chemisorption process in ${\alpha}$ phase of thinner films, and diffusion process in ${\alpha}'$ phase of thicker films respectively.

• 대한치과보철학회지
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• 제8권1호
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• pp.25-29
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• 1968

The purposes of this study were to measure the film thickness of zinc phosphate cement between the casting restorations and preparation walls. In addition, the differences between finger press and non press techniques after the castings were seated completely on the preparation by an automatic mallet until the cement set were studied. The results were as follows : 1) In full cast crown, the cement film thickness on the side wall was thinner than that on the other walls. 2) In 3/4 crown and inlay, the cement thickness was thinner than that in cast crowns. 3) The cement of great W/P ratio showed thinner thickness than that of little W/P ratio. 4) The continuous finger press after the castings were seated completely on the preparations had few influence on the cement film thickness.

• Journal of Preventive Medicine and Public Health
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• 제15권1호
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• pp.213-217
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• 1982

Self sensing symptoms were. surveyed by interview from the workers using lacquer-thinner(Male 35, Female 28). And the data was converted to point. Independent variables were state of the medication, education, alcohol drinking, smoking, living and past occupational history. Dependent variable was the point. The relationship between independent variables and the depenent variable was studied. The result of the study were briefly summarized as below. 1. The difference of point between sex and medication statement was significant by statistical test. 2. Age and past occupational history were not important variables. 3. The Multiple Stepwise Regression Equation obtained by this study was not useful.

• Plant Resources
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• 제7권2호
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• pp.123-126
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• 2004

New thornless cultivar of castor aralia(Kalopanax septemlobus Koidz.) was developed and selected in Cheongsong, Prov. of GyeongSangbuk-do during the period from 1994 to 1999 by Korea Forest Research Institute(KFRI). The new thornless cultivar, "Cheongsong II" is characterized by a thinner outer-bark and soft, wider leaves, and is particularly characterized by thornless stems. This cultivar has a thinner outer-bark(8.82mm) when compared with thorned type trees(13.95mm). It also has a larger leaves than does thorned type trees. Consequently, the new thornless cultivar, "Cheongsong II" is defined to have thinner bark and longer and wider leaves than do other thorned type trees. thorned type trees.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.173-176
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• 2008

The purpose of this study was to use case analysis and experimentations to examine the ignition characteristics of the cigarette lights on corrugated board and oils etc. As a result of the tested. The corrugated board could be ignited by cigarette light, but gasoline and lacquer thinner could seldom be ignited.

• Composites Research
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• 제27권1호
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• pp.25-30
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• 2014

실리콘 KE-12, NBR 그리고 NR 등의 유전 탄성체 종류, 두께 및 희석제 함유량을 함수로 한 전기활성 유전탄성체(EADE) 구동 성능에 대해 연구하였다. 탄성체의 두께($1{\rightarrow}0.5{\rightarrow}0.25{\rightarrow}0.1{\rightarrow}0.05$ mm)의 감소에 따라 그리고 희석제의 함유량 증가에 따라 KE-12 탄성체의 작동변위는 증가하였지만, 유전파괴는 낮은 전압에서 발생되었다. 동일한 탄성체 두께(1 mm)에 대해서 KE-12의 변위(2.24 mm)는 동일한 전압(25 kV)에서 NBR 혹은 NR보다 더 높게 나타났다. 시험한 탄성체 종류 중 KE-12는 가장 낮은 탄성계수를 NBR은 가장 높은 탄성계수 나타냈다. 하지만, NBR 탄성체의 변위는 높은 유전상수 때문에 NR의 경우 보다 높았다. EADE 구동기의 중요한 요소는 탄성체의 두께, 탄성계수 및 유전상수임을 확인하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.60-65
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• 2007

According to the customers' demands, cellular phones are getting thinner and thinner in spite that their functions are getting more complex and flexible. Based on this trend, we are willing to propose new design of ultra slim cellular phone with multi-hinges which can provide thinner feature and wider active area than the current merchandised one. To make it come true, smaller and stronger mechanical parts would be necessary and more researches would be carried out in the near future. Moreover, the new frame of ultra slim cellular phone has the problem in heat propagation due to its thin feature and multi function. In this paper, slim heat-spreader would be proposed as a candidate to resolve the problem of heat transfer in the new cellular phone. To investigate the applicability of heat-spreader to cellular phones, prototypes were fabricated and verified.

• 대한지역사회영양학회지
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• 제2권2호
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• pp.197-205
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• 1997

This study was conducted to investigate adolescents' body size and their concerns and perceptions about body image. Group means of heights and weights were 171.5cm and 60.3kg for boys and 159.3cm and 52.3Kg for girls. Body Mass Index(BMI) of the subjects were 20.5 for boys and 20.6 for girls. Only 11.5$\%$ of subjects were overweight or obese, however 42.5% of subjects had experienced weight control, and the main reason for weight control was to lose weight(80.6$\%$). In concern for body image and frequency of eating distrubance ; females had more concern than males, the group who had attempted weight control had more concern than those who had not, and the group who were overweight had more concern than those who were under and normal weight. In perception about body image, using a set of nine figure drawings arranged from very thin to very heavy figures, subjects rated their current figure, considered figure(how they appeared to others), ideal figure, and attractive figure. For boys, the current, ideal, and most attractive figures were almost identical, but for girls, the ideal figure was significantly thinner than current figure and attractive figure was significantly thinner than current figure. The greater the preference for thinner figure as idal and attractive figure, the higher the concern for body image and frequency of eating distrubance. Thus it seems that a distorted perception of ideal body size affects adolescents' concern for body image and eating behaviors.