• Korean Journal of Materials Research
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• v.23 no.10
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• pp.543-549
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• 2013

The purpose of this paper was to investigate the effect of a high-energy milling (HEM) process on the particle morphology and the correlation between a thermal treatment and tetragonal/monoclinic nanostructured zirconia powders obtained by a precipitation process. To eliminate chloride residue ions from hydrous zirconia, a modified washing method was used. It was found that the used washing method was effective in removing the chloride from the precipitated gel. In order to investigate the effect of a pre-milling process on the particle morphology of the precipitate, dried $Zr(OH)_4$ was milled using a HEM machine with distilled water. The particle size of the $Zr(OH)_4$ powder exposed to HEM reduced to 100~150 nm, whereas that of fresh $Zr(OH)_4$ powder without a pre-milling process had a large and irregular size of 100 nm~1.5 ${\mu}m$. Additionally, modified heat treatment process was proposed to achieve nano-sized zirconia having a pure monoclinic phase. It was evident that two-step calcining process was effective in perfectly eliminating the tetragonal phase, having a small average particle of ~100 nm with good uniformity compared to the sample calcined by a single-step process, showing a large average particle size of ~300 nm with an irregular particle shape and a broad particle size distribution. The modified method is considered to be a promising process for nano-sized zirconia having a fully monoclinic phase.

• Fashion & Textile Research Journal
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• v.7 no.5
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• pp.472-480
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• 2005

It was proved the practical use of the unique traditional Korean paper through the previous researches. The purpose of this study was to suggest the adequate application which is making various applied patterns in the fashion products so as to contribute to textile, fashion, and Korean paper industry. Six kinds of vests with the same fashion material using the Korean traditional paper were manufactured in order to investigate the images of materials in case of wearing them on the actual human bodies. As the results of image assessment for the materials and the factor analysis, 'classical', 'natural', 'Korean traditional', 'rural' and 'luxury' images were presented as the representative image of the Korean traditional paper material. Making repeated patterns of stripes and zigzag by sewing-machine stitches showed the natural effect on Korean traditional paper. Well-matched harmony was shown between holes made by the needle in sewing and slits torn by the tension to the needle and the thread. Especially, transparency by irregular holes formed by artificial frictional washing could shown special formative arts harmoniously with semi-transparency of Korea traditional paper and touch of sewing yarn. After the unripe persimmon dyeing, holes made by the needle became more hard and tight. The changes were no longer shown by the artificial frictional washing and then fixed. As the result of applying the Korean traditional paper fashion materials with various patterns for the basic formed garments, it was shown that the common and simple garments were changed the garments with special formation which could be found on the art garments due to the creative touch and formative arts using the Korea traditional paper fashion material. A variety of formative application by means of the developed samples was suggested to enlarge the practicality. As the result of this study, it was discovered that the possibility and application of fashion goods through the developed samples made of Korean traditional paper.

• Journal of the Korean Society of Clothing and Textiles
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• v.6 no.1
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• pp.9-15
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• 1982

The influence of builders on calcium deposition on the fabric was studied by laundering the cotton fabric with sodium carbonate, sodium metasilicate, sodium tripolyphosphate and built detergents in hard water. The laundry variables were: 1) Washing cycles: 5, 10, 20, 30 and 40 cycles. 2) Water hardness: 100 ppm, 150 ppm, 200 ppm and 300 ppm. 3) Builders: $Na_2\;CO_3,\;Na_2\;SiO_3$ and STPP. 4) Detergents: Na-DBS, $Na-DBS+Na_2CO_3,\;Na-DBS+Na_2\;SiO_3,\;Na-DBS+STPP,\;Na-DBS+Na_2\;CO_3+STPP$, and $Na-DBS+Na_2\;SiO_3+STPP$. The fabric was washed for 15 minutes at 23+$1^{\circ}C$ in a washing machine(Gold Star WP 3007) under the similar condition with those of home laundering, and rinsed 3 times in the same water hardness for 5 minutes. The calcium deposits on the fabric was determined by EDTA-BACK titration methods. The results of this study were as follows: 1) The amount of calcium deposits on the fabric was increased with increasing wash cycles. This deposit was due to the build up of insoluble calcium carbonate. 2) As the water hardness increased, the amount of calcium deposits on the fabric was increased. 3) Alkaline builders, such as, $Na_2CO_3$ and $Na_2SiO_3$, promoted calcium deposition on the fabric, however STPP prevented calcium deposition on the fabric. 4) Fabric laundered with $Na-DBS+Na_2CO_3$ showed the highest calcium deposits on the fabric, and decreased with the order of $Na_2CO_3$, $Na-DBS+Na_2SiO_3$, and Na-DBS. And fabrics washed with phosphate-built detergents showed a small amount of calcium deposition.

• Journal of IKEEE
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• v.23 no.2
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• pp.543-551
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• 2019

Permanent Magnet Synchronous Motors(PMSMs) have a wider range of applications due to their high output density and high efficiency. PMSMs are used not only in high-power density, high-performance motor-driven systems such as vehicle and robots, but also in systems where cost-cutting is very important, such as washing machines, air conditioners and refrigerators. To reduce costs, position sensorless control is required, which is generally difficult to be used under conditions of starting the motor. Thus, the I-F speed control that rotates the current vector at any speed in the starting procedure should be used at first, and then the sensorless speed control could be applied after PMSM rotates above a certain speed. Speed control performance in I-F speed control and sensorless speed control is very important. And more speed control performance should be maintained even in the transient in which the two control techniques are changed. In this paper, the speed controller transition method from I-F speed control to sensorless speed control of permanent magnet synchronous motor is proposed. Experiments were carried out on the washing machine drive system to verify the performance of the proposed technique.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

• Environmental and Resource Economics Review
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• v.24 no.3
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• pp.463-488
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• 2015

A more detailed design of offset system is needed according to the emission trading system started in 2015. This study aims to estimate the supply of potential offset that can be secured by expanding high-efficiency household electric appliances. The target commodities for analysis are three different householding electric appliances: TV, washing machine, electric fan, refrigerator and air conditioner. By using the ARDL model, we estimated the coefficients of diffusion of these high-efficiency appliances from 2016 to 2022. Then, the potential supply of offset was drawn by calculating the amount of electricity saving by efficiency improvement and by applying the rates of carbon exchange. Supposing that the electricity savings rates of high-efficiency appliances are each 10% and 20%, the accumulated carbon decrement in 2022 was respectively $361,899CO_2t$ and $723,797CO_2t$. The appliance that showed the biggest carbon decrement was air conditioner, and the second biggest was refrigerator and the next was TV, followed by washing machine, electric fan.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.571-575
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• 2019

Fungal occurrence during production of dried red pepper was investigated using red pepper samples collected at harvest, before and after washing, and before, during or after drying. Fungal incidence was evaluated by counting the number of fungal colonies grown after incubating random pepper cuts on potato dextrose agar plates. Washing with ground water had no significant effect on reduction of fungal contamination. Fungal increase was observed in some samples, and the insides of washer and containers were contaminated with fungi. Drying caused significant fungal increase regardless of drying method although the fungal incidence after machine drying was lower than that after greenhouse drying. Fungal increase was observed in the samples being dried in a greenhouse and some mycotoxigenic species were also detected. Therefore, the most important control point for fungal contamination during dried pepper production appears to be the drying process, especially in a greenhouse.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1784-1792
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• 2007

This study set out to identify the problems with hat labels and to search for improvement measures by examining and analyzing consumers' practice of managing their hats. It also intended to provide accurate and enough information about how to keep and wash hats and thus help consumers use their hats for a long period. In an attempt to investigate how consumers wash and manage their hats, a survey was carried out to 395 individuals in their twenties and over who owned hats living in urban areas including Seoul, and were quota sampled according to age and gender. The survey period is March to April 2007. The collected data were statistically treated with the SPSS 12.0 program in terms of frequency, percentage, mean, standard error, cross tabulation, t-test, and one-way ANOVA. The findings were as followed. First, the respondents were in the average level of perceiving and practicing the washing methods of their hats. The female respondents who had more experiences with laundering than the males knew and practiced the washing methods for hats better than males. Second, compared to other clothing items, hat wearers were more likely to pay careful attention to their hats by putting their hats in a laundry net and applying a laundry detergent for wool fabrics when using a washing machine or washing their hats with their own hands. And third, most of the hat wearers were aware of the importance of hat labels and showed a lower level of trust in them than other clothing items. The suppliers need to offer accurate and practical labels in order to regain the consumers' trust. Many consumers had some difficulties figuring out the size system of hats. In particular, the male consumers had a low level of perception of labels, which implies that there should be specific efforts to educate them about general labels.

• Fashion & Textile Research Journal
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• v.2 no.4
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• pp.331-338
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• 2000

To study on the actual condition of care label attached to clothing and consumers' perception, 250 summer clothes sold at department store-blouse, trousers, one-piece dress, knit cardigan and skirt-were investigated during July 2000. In addition, a questionnaire was administered to 192 women in Taegu during August. The fiber contents of surveyed clothes were polyester 100% & polyester blend (26%), rayon 100% & rayon blend (18%), cotton 100% & cotton blend (17%), wool 100% & wool blend (14%) and others. All clothes surveyed were attached care label and the signals showed on care labels were 4~6 kinds about cleaning, squeezing, drying, bleaching, and ironing methods. 92% of clothes had to be dry-cleaned and only 8% could be wet-cleaned. Considered the surveyed clothes were for summer which needs frequent washing and the clothing items, the number of clothes had to dry-cleaned were too many. The bleaching instructions were no chlorine bleach (74%), no bleaching (21%) and others. The ironing instructions were cool ironing ($80{\sim}120^{\circ}C$) with cover (24%) and warm ironing ($140{\sim}160^{\circ}C$) with cover (69%) primarily. The drying instructions was dry on a hanger in the shade (54%) and 38% had no signal or incorrect signal. The properties of summer clothes considered important by consumers were wrinkled hardly, hand-washable, machine-washable, needed no iron and etc. Actually most of summer clothes were hand or machine-washed. Also, the majority of respondents felt inconvenient to have to dry-clean summer clothes. More than 80% respondents looked over care label and fiber content label before buying clothes. However most of respondents did not followed that instructions exactly and thought care label instructions were not correct. Considered this results, the suppliers have to make efforts to attach correct and appropriate care label which furnish the correct information to consumers.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.6
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• pp.630-633
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• 2001

This paper propose electronic speckle pattern interferometry(ESPI) for reliability evaluation of electronic device. Especially, vibration problem in a fan of air conditioner, motor of washing machine and etc. is important factor to design the devices. But, it is difficult to apply previous method, accelerometer to the devices with complex geometry. ESPI, non-contact measurement technique applies a commercial fan of air conditioner to vibration analysis. Vibration mode shapes, natural frequency and the range of the frequency are decided and compared with that of FEM analysis. In mechanical deign of new product, ESPI adds weak point of previous method to supply effective design information.