• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.10
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• pp.10-16
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• 2008

Generally, the satellite circling round in a low orbit goes through Van Allen belt connecting with the magnetic fold, in which electronic components are easily damaged and shortened by charged particles moving in a cycle between the South Pole and the North Pole. In particular, Single Event Upset(SEU) by radiation could cause electronic device on satellite to malfunction. Based on the idea mentioned above, this study considersabout SEU effect on the On-board Computer(OBC) of STSAT-1 in the space environment radiation, and shows algorithm to cope with SEUs. In this experiment, it also is shown that the repetitive memory read/write operation called memory wash is needed to prevent the accumulation of SEUs and the choice for the period of memory wash is examined. In conclusion, it is expected that this research not only contributes to understand low capacity of On-board Computer(OBC) on Low Earth Orbit satellite(LEOS) and SaTReC Technology satellite(STSAT) series, but also makes good use of each module development of Korea Multi-Purpose Satellite(COMPSAT) series.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.2
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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.

• Journal of the Korean Society of Costume
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• v.56 no.7 s.107
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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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.

• Journal of Conservation Science
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• v.33 no.2
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• pp.97-106
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• 2017

The purpose of this study was to investigate the characteristics and detergency of natural surfactants for the cleaning of excavated fabrics. For this purpose, SDS, a synthetic surfactant, was selected as the control, and five types of natural surfactants, namely, LES, apple wash, tea saponin, cornacopa, and coco betaine were selected. The structures of the surfactants were confirmed by FT-IR spectroscopy analysis, and the characteristics of the surfactants were determined by measuring the pH and surface tension. In addition, detergency testing was carried out on four artificially soiled fabrics and fragments of excavated fabrics. From the results, apple wash, tea saponin, and cornacopa were found to be as good as SDS in terms of detergency in the cleaning of artificially soiled fabrics, and the detergency of tea saponin and coco betaine was found to be good for cleaning excavated fabrics. Therefore, considering the safety and detergency of detergents, among natural surfactants, tea saponin is found to be most suitable for the cleaning of excavated fabrics.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.2
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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.

• Journal of Families and Better Life
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• v.7 no.2
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.4
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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.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.463-468
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• 2004

A lab-scale fundamental study to develop the solvent extraction process of ship wash wastewater containing TBT was carried out. For various solvents, including diesels for car and ship, bunker B, thinner, toluene, and ether, the extraction efficiencies of TBT from synthetic ship wash wastewater were compared The effect of extraction conditions, such as solvent amount, time and intensity of agitation, and pH, on the extraction efficiency of TBT was evaluated Diesel for ship showed better extraction efficiency of TBT than those of other tested solvents, and the proper amount of the extraction solvent for 1L of the wastewater was l0mL. When the agitation intensity was increased from 50rpm to 250rpm, the TBT remained in the wastewater after the extraction was decreased from around 120ppb to 2.8ppb. The remaining TBT in the wastewater was sharply decreased from 1hr of the extraction time, but was slightly increased again after 5hrs of the extraction time. The efficiency of TBT extraction was good in the weak acid range of pH, but was not significant as much as the others.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.137-146
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• 2011

Development of mobile devices such as smart phones and tablet PC and increased usage for mobile contents make researches of mobile computer graphics noticeable. However, previous non-photorealistic renderings such as an ink-and-wash painting with thin colors are almost designed for desktop platform and not well-matched for mobile devices. In the result, mobile-specific rendering techniques are needed to create 3D mobile contents with non-photorealistic graphics. We introduce processing techniques that are especially ink-and-wash painting and oriental thin coloring in mobile devices. Through the result of this paper, it is expected that various 3D mobile contents with non-photorealistic styles are made. Proposed work also can allow mobile devices render it in realtime using proposed preprocessing techniques and rendering pipelines.