• 대한전자공학회논문지TC
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• 제45권10호
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• pp.10-16
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• 2008

보통 저궤도를 선회하는 위성은 자기장으로 연결된 반알렌대를 통과하며, 이 안에 갇혀 주기적인 운동으로 남극과 북극을 이동하는 하전입자에 의해 부품이 손상되고 수명이 단축되는 악 영향을 받고 있다. 그중 방사선에 의한 SEU (Single Event Upset) 등은 우주선에 탑재된 반도체 소자의 오동작 유발의 원인이 되고 있다. 본 연구에서는 우주환경 방사선에서 고려해야 할 점들 중에서 특히 과학기술위성 1호 탑재 컴퓨터(On-board Computer, OBC)에서의 싱글이벤트업셋(Single Event Upset, SEU)의 영향을 고찰해 보고 거기에서 극복할 수 있는 알고리즘을 제시하고 있다. SEU 누적을 방지하기 위하여 매 일정한 시간마다 전체 메모리를 읽고/쓰는 과정(memory wash)이 필요하며 워쉬 주기 선정에 대해서도 고찰했다. 이러한 실험은 과학기술위성 시리즈 및 저궤도 위성용 탑재 컴퓨터의 성능 저하를 이해하는데 도움을 줄 수 있을 뿐만 아니라, 다목적 실용위성 시리즈의 각 모듈 개발에도 적극 활용 할 수 있을 것으로 기대된다.

• 대한치과보철학회지
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• 제34권2호
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• pp.373-383
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• 1996

In order to compare the accuracy of impression method using addition silicone putty impression material, metal master die was fabricated with 4 cylindrical abutments that were similar in shape to mandibular arch. Among the 4 abutments, two(A, D) with 8mm width and 7mm height were formed in the 2nd molar regions and the other two(B, C) with 6mm width and 7mm height were on the canine regions. Impressions were taken using one-step putty wash impression technique and two-step putty wash impression technique by three different types of impression materials(Perfect, Express, Exaflex). Upon measuring the distance between the abutments on the model by three dimensional measuring machine, the percent of devitaion of the materials were obtained, rendering the following results. The results obtained are as follows : 1. There was no significant difference in accuracy in regard with the impression method between one-step putty wash impression technique and two-step putty wash impression technique using addition silicone putty impression material. 2. There were no difference in accuracy among with three different addition silicone putty impression materials. 3. All the distances between abutments on improved stone models increased in comparison with those on the metal master model.

• 복식
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• 제56권7호
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• pp.18-32
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• 2006

The objectives of this research were to identify the differences of image evaluations by perceiver's gender, majors and jeans' finishing and to examine image characteristics that have an influence on attractiveness and preferences of jeans' finishing. The subjects are 96 undergraduate students in Los Angeles of the USA. Elegant and refined images had a significant effort on perceiver's gender, so men tended to highly evaluate jeans as elegant and refined images than did women. Soft images were recognized differently by perceiver's major, so non-specialists in design tended to highly evaluate jeans as soft images than did specialists in design. In finishing, shattered wash was evaluated as the most individual, attractive, energetic, and splendid images, and stone wash was evaluated as the most ordinary, unattractive, and plain images. Light images tended to have interaction effects by majors and finishing. Specialists in design did not perceive differences between light images from finishing well, but non-specialists in design perceived that stone wash finishing's image is lighter than indigo blue finishing's image. Sociable images had interaction effects by perceiver's gender, majors and jeans' finishing, and especially non-specialists in men estimated that shattered wash has the lowest sociable images in finishing. According to evaluations about finishing images of ladies' jeans, men tended to be attracted by splendid images, and women tended to be attracted by sexy images. In addition, both men and women were commonly attracted by feminine images, so the study found that feminine images is important image for developing jeans for ladies. According to evaluations about finishing images of ladies' jeans, men preferred sexy and natural images to comfortable and energetic images, and women preferred sexy and neat images. Female undergraduate students of the USA tended to be attracted by sexy images, and we found that actually they consider buying jeans with such images.

• 한국의류학회지
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• 제30권11호
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• pp.1589-1597
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• 2006

Nowadays, Korean consumers prefer drum-type washing machines to pulsator-type washers. Washing is a complex process involving the interaction of numerous physical and chemical influences. The main factors in the washing operations are the washing chemistry of the detergent along with the mechanical input, the wash temperature, and the time provided by the washing machine. Heavy-duty detergents that are used in drum-type washing machines contain different components from those used in vertical-axis washing machines. The bath ratio and the mechanical actions to which laundry is subjected are different between the drum-type and the vertical-axis washing machines. In this study we examined the effects of wash temperature, wash time, detergent concentration, and revolution speed on the removal of soils from artificially soiled cloths in a drum-type washing machine with heavy-duty commercial detergent. We used multiple regression analyses to find the relative importance of the factors and the optimum washing conditions. The results of these experiments showed that the washing temperature was the most important factor in the effective removal of most soils. This was followed by the washing time, the detergent concentration, and finally the revolution speed. In this study it was found that superfluous amounts of detergent did not sufficiently increase the soil removal rate. Koreans who are used to washing with cold water should increase the wash time to launder more efficiently.

• 보존과학회지
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• 제33권2호
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• pp.97-106
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• 2017

본 연구는 출토직물의 세척을 위한 천연계면활성제 선정을 위하여 그 특성과 세척성을 알아보는데 목적이 있다. 이를 위해 대조군으로 합성계면활성제인 SDS (Sodium dodecyl sulfate)와 천연계면활성제 중 LES (Disodium laurethsulfosuccinate), apple wash (Sodium cocoyl apple amino acids), tea saponin (Saponin), cornacopa (Decyl glucoside), coco betain (Cocamidopropyl betaine) 등 5종을 선별하여 계면활성제의 FT-IR (Fourier transform infrared spectroscopy) 분석으로 구조를 확인하고, pH와 표면장력 측정으로 특성을 파악하였다. 인공오염포 4종과 출토직물편에 대한 세척성 실험을 수행하였다. 그 결과 인공오염포에 대해서는 apple wash, tea saponin, cornacopa가 세척성에 있어서 SDS만큼 좋은 것으로 나타났으며 출토직물편에 대해서는 tea ssponin과 coco betain의 세척성이 좋은 것으로 나타났다. 따라서 세제의 안전성과 세척성을 감안할 때 천연계면활성제 중 tea saponin이 출토복식 세척을 위한 천연계면활성제로써 적합한 것으로 사료되었다.

• 대한치과보철학회지
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• 제38권2호
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• pp.191-199
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• 2000

Wettability of addition silicone impression material is very important property for making an accurate restoration. This study examined the impression quality in clinical condition and the wettability of impression and die material. Four commercially available addition silicone impression material (Express, Examix, Contrast, Perfect) and three die materials (Die-Keen, Vel-Mix, Fuji-Rock) were studied. A total of 50 putty/wash and heavy body/wash impressions of wet intact permanent molar teeth were examined for definition of the gingival sulcus reproduction and then classified in quality ranking. The percentage of the sulcus reproduction ability of each material was calculated from the sulcus depths of cross-sectioned epoxy resin casts from the impressions and clinically measured sulcus depths, The same impression materials were used to produce 3 groups of die stone casts form void entrapment die had been exposed to milk. Voids in the impression body and stone casts ere counted under a stereoscopic microscope. From the experiment, the following results were obtained : 1. Sulcus reproduction ability of additional silicone impression material were diminished in order of Express, Examix, Perfect, Contrast. The significant difference was found between Perfect and other material. Heavy body/wash combination was superior In putty/wash method n Perfect impression material. 2. In direct observation, Contrast showed least void in impression body but correlations ere not found between sulcus reproduction and void production. 3. In void entrapment laboratory test, wettability were diminished in order of Examix, Contrast, Express, Perfect. Clinical impression recording seems not to correlate with laboratory test. 4. The wettability of die material to impression material was not different in Express, Examix, Contrast. But, in Perfect, Die-Keen had superior wettability to others.

• 가정과삶의질연구
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• 제7권2호
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• pp.95-107
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• 1989

In this study one aspect of consumer behavior in household equipment utilization was investigated the pattern, frequency, rate of washer use and their relation to the following factors a) Washer related factors : extent of the presence of desired characteristics, the evaluation of washer's intrinsic features and related household facilities. b) Psycho-social factors : attitude of energy conservation, preference & ability to wash by hand, standard of washing of the respondent homemaker. c) Socio-demographic factors : age, education level and employment status of homemaker, house-hold income, the presence of children under seven years, size of family, the presence of a paid help. The subjects of this study were 286 homemakers with washer in Seoul. Analysis methods were used to fuequency, one-way ANOVA, Gamma test, Pearson's Correlation Coefficient, t-test and multiple regression of SPSS program. The major findings are the following; 1) The pattern, frequency, rate of washe use appeared various in every household. 2) Extent of the presence of desired characteristics was very low and respondents evaluated their washer's intrinsic features moderate. 3) The pattern of washer use was affected by the evaluation of washer's intrinsic features, preference & ability to wash by hand, wife's employment and household income. The frequency of washer use was affected by family size and preference & ability to wash by hand. The rate of washer use was affected by extent of the presence of desired characteristics, the evaluation of washer's intrinsic features and preference & ability to wash by hand. Therefore, washing by hand is major substitute for washer. If more desired characteristics are added to washer, intrinsic features are improved, and maintenance costs are reduced or household income is raised, every houshold with washer will use washer more than washing by hand in washing ask so that it may gain more utility from washer.

• 한국의류학회지
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• 제18권4호
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• pp.549-559
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• 1994

The purpose of this study was to study accumlated residual soils which may be one of the causes for yellowing of worn cloths. Wear and wash tests of white cotton undershirts were repeated at 30 households sellected at random over a period of 60 days. Laundry conditions were similar to home laundry habits in a fact-finding survey, using a powdery heavy duty detergent containing no enzymes or enzymes. The subjects in this study were survey of laundry actual condition, the undershirts from prior to and after the final washing was measured residual soils, $L^*a^*b^*$ value and mellowness index of CIE system. D3ta were analysed by simple correlation analysis of wear and wash cycle, residual soils, whiteness The results obtained were summarized as follows: 1. Using pattern of washing machine, Presoaking was no singinificant differnece in general characteristics of survey respondent. Laundry frequency was significant difference in income level, occupation of housewives whether or not. Use of cold and hot water was significant difference in residence shape. 2. The analyzed consequences of recognition and actual behavior in connection with laundry were found variables each other to have independence or not. 3. Amount of residual sebum soils is using non-enzyme detergent were much more than in using enzyme detergent, increased linearly with increase of the number of wear and wash cycles. 4. Residual protein soils with increase of the number wear and wash cycles less than in laundering more easy than sebum soils. Since accumulated residual sebum soils were much more than residual protein soils. 5. Increase of residual soils was raised mellowness index and diminshed whiteness. yellowness index of residual sebum soils was higher than protein soils. If increase of whiteness will be incresed, amount of residual sebum soils will be decreased sebum soils. Because amount of residual sebum soils much more than protein soils, yellowness index of residual sebum soils was more higher than that of protein soils.

• 한국항해항만학회지
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• 제28권5호
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• pp.463-468
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• 2004

수리조선소에서 발생하는 TBT 함유 선박세척폐수의 용매추출 처리기술을 개발하기 위한 기초연구로서 인공 선박세척폐수를 이용하여 선박용 및 자동차용 디젤, 벙커 B유, 신너, 톨루엔, 에테르 등의 여러 가지 용매들의 TBT 추출효율을 비교하였으며, 추출효율에 대한 추출용매의 양 및 교반시간, 강도, pH 등의 추출조건의 영향을 평가하였다. 선박용 경유는 신나, 병커B 등에 비해 상대적으로 우수한 TBT 추출효율을 보였으며, 적정 추출용매 주입량은 폐수 IL 당 용매 10mL로 평가되었다 TBT 추출을 위한 교반강도가 50rpm에서 250rpm으로 증가함에 따라 잔류 TBT 농도는 약 120ppb에서 2.8ppb로 크게 감소하였다 잔류 TBT는 추출 1시간이후 크게 감소하였으며, 5시간 이후부터는 다시 증가하였다. 추출효율에 대한 Ph의 영향은 크지 않았으나, pH 6∼7의 약산성영역에서 양호한 추출효율을 보였다.

• 한국콘텐츠학회논문지
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• 제11권3호
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• pp.137-146
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• 2011

스마트폰과 태블릿 PC 같은 모바일 기기의 보급과 콘텐츠 사용 증가로 모바일 환경에서의 컴퓨터 그래픽스 연구가 활발하게 진행되고 있다. 그러나 아직까지 수묵화 및 담채 렌더링 기법과 같은 비실사적 기법을 모바일 기기 상에서 효과적으로 구현하기 위한 연구는 부족한 편이다. 모바일 기기는 데스크 탑 환경에 비해 하드웨어적 한계를 가지고 있기 때문에 비실사적 렌더링 기법이 적용된 콘텐츠를 렌더링 하기 위해서는 단말기의 제약성을 고려한 특화된 렌더링 파이프 라인이 필요하다. 본 논문에서는 비실사적 기법중에서도 수묵화 기법과 담채화 기법을 모바일 환경에서 구현하기 위한 3차원 그래픽스 렌더링 파이프라인과 쉐이딩 파일 전처리 기법을 제안한다. 제안하는 기법을 이용하면 비사실적 렌더링이 적용된 다양한 3D 모바일 콘텐츠를 생성할 수 있고 사용자는 모바일 디스플레이 환경에서 실시간으로 수묵 담채 렌더링 된 콘텐츠를 볼 수 있을 것으로 기대한다.