• Title/Summary/Keyword: Stability and Consistency

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A Study of stability in ratings for clothing and their woven fabrics (의복과 그 직물에 대한 평가의 재현성 차이에 관한 연구)

  • 유경숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.3
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    • pp.560-568
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    • 2001
  • The aim of the present study was to measure intra-individual consistency in clothing and fabric evaluation and to examine its relation to the ratings. A sample of 93 female and 97 male university students rated clothing of 4 styles of daytime wear and 2 fabrics on 15 pairs of polar adjectives twice in 7-days interval. Correlation coefficients between the two ratings for each subject, intra-individual consistency in the evaluation, ranged from -0.12 to 0.89 and mean coefficient was 0.63 of female and -0.01 to 0.78 and mean coefficient was 0.54 of male. Based on the coefficients, the subjects were classified into three groups: high, medium, and low intra-individual consistency. Analysis of variance of mean ratings by the three groups revealed that significant difference existed in 24% of female and 23% of male in 90 combinations of 6 clothing and 15 semantic differential scales. Female of subjects with high intra-individual consistency were most likely definite to evaluate clothing, whereas the ones with low were least. But male subjects were not definite. Mean correlation coefficients for style evaluation subscales of female was 0.39, but male was 0.44. Among the semantic differential scales, high stability in the two ratings was observed for the synthetic clothing evaluation. Correlation coefficients for each clothing obtained from the mean score of the subjects in each semantics differential scale were around 0.98, including that the mean scores of the subjects in each scale could yield excellent stability in clothing evaluation.

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The Stability of Yin-Yang Temperament in Middle School Students (중학생에 있어서 음양 기질의 안정성)

  • Lee, Soo Jin;Chae, Han
    • Journal of Sasang Constitutional Medicine
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    • v.31 no.1
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    • pp.94-101
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    • 2019
  • Objectives The Yin-Yang construct was shown to have stable internal reliability or consistency using Sasang Personality Questionnaire (SPQ) throughout the various ages, however the study of stability over specific period of time was only conducted using adults. The purpose of the study was to examine the stability across the time using middle school students whose physical and psychological characteristics were most rapidly changing. Methods The 122 middle school students (65 boys and 57 girls) completed the SPQ at 1st year and 2nd year with one-year time difference. Cronbach's ${\alpha}$ and Pearson's correlation analysis were employed in order to show the internal consistency and stability over one-year interval after considering sex difference. Results The internal consistency of SPQ-T, SPQ-B, SPQ-C, SPQ-E using Cronbach's ${\alpha}$ were .61, .72, .28, .28 in 2016 and .62, .72, .26, .46 in 2017. The one-year test-retest reliability of SPQ-T, SPQ-B, SPQ-C, SPQ-E using Pearson's correlation analysis were .56, .61, .31, .23 in boys and .58, .63, .64, .29 in girls. Conclusion The current study showed the stability of Yin-Yang temperament across the one-year time suggesting that the Yin-Yang temperament is quite stable and measurable concept and the SPQ would be considered as an objective and reliable personality assessment.

Studies on Semisolid Infant Foods (III)-Rheological Properties of the Products- (반고체 이유보충식에 관한 연구 (III)-생물학적 조사-)

  • 이영춘
    • Journal of Nutrition and Health
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    • v.19 no.1
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    • pp.3-15
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    • 1986
  • This study was intended to investigate the rheological properties of the development formula of infant foods and the results are summarized as follow ; 1) Consistency of starch solutions measured by Brabender Anylograph and Brookfield viscometer showed that waxy rice and riece with malt had lower consistency and more rheological stability.The flow type of tested raw materials and formula was found to ? pseudoplastic, as judged by n-value of 0.332 -0.692, and no yield value. 2) The influenced of temperature on consistency could be accounted for by the equation, In (n) = K(1/T) + const. this relationship indicated that consistency of tested sample increased as temperature decreased. The consistency of waxy rice, rice with malt and formula A were less affected by the temperature change. 3) Infant foods with malt(formula A ) ad with waxy rice maintained better freeze-thaw stability in terms of consistency and starch aggregation indicating that this infant food could be stored for a long term in the freezer section of the home refrigeratory without adverse effect on the product quality. 4) From the above experiments, it would necessarily follow that infant food can be easily made at home the food-stuffs generally available around us, and that the easiest and safest way to store them lies in making them into semisolid state, and in keeping them in frozen state.

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Stability of High Internal Phase Emulsions

  • Park, C.I.;Cho, W.G.
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.25 no.4 s.34
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    • pp.65-74
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    • 1999
  • We have studied the stability of W/O high internal phase emulsions(HIPE) containing water, cetyl dimethicone copolyol and oils varying magnesium sulfate in the range 0 to 0.5 wt% and oil polarities, respectively. The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The greater the increase of complex modulus was, the less coalescence occurred and the more consistent the concentrated emulsions were. The increasing pattern of complex modulus versus volume fraction has been explained with the resistance to coalescence of the deformed interfacial film of water droplets in concentrated W/O emulsion. The stability is dependent on: (i) the choice of the oil is important, the requirements coincide with the requirements for the formation of the rigid liquid crystalline phases; and (ii) addition of salts the aqueous phase opposes the instability due to coalescence. Increasing the salt concentration increases the refractive index of the aqueous phase. It lowers the difference in the refractive index between the oil and aqueous phases. This decreases the attraction between the water domains, thus increasing the stability.

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Stability of High Internal Phase Emulsions

  • Park, C-I.;W-G. Cho
    • Proceedings of the SCSK Conference
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    • 1999.10a
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    • pp.65-74
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    • 1999
  • We have studied the stability of W/O high internal phase emulsions(HIPE) containing water, cetyl dimethicone copolyol and oils varying magnesium sulfate in the range 0 to 0.5wt% and oil polarities, respectively. The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The greater the increase of concentrated modulus was, the less coalescence occurred and the more consistent the concentrated emulsions were. The increasing pattern of complex modulus versus volume fraction has been explained with the resistance to coalescence of the deformed interfacial film of water droplets in concentrated W/O emulsion. The stability is dependent on: (i) the choice of the oil is important, the requirements coincide with the requirements for the formation of the rigid liquid crystalline phases :5; and (ii) addition of salts the aqueous phase opposes the instability due to coalescence:. Increasing the salt concentration increases the refractive index of the aqueous phase. It lowers the difference in the refractive index between the oil and aqueous phases. This decreases the attraction between the water domains, thus increasing the stability.

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Emulsion stability of cosmetic creams based on water-in-oil high internal phase emulsions

  • Park, Chan-Ik;Cho, Wan-Gu;Lee, Seong-Jae
    • Korea-Australia Rheology Journal
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    • v.15 no.3
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    • pp.125-130
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    • 2003
  • The emulsion stability of cosmetic creams based on the water-in-oil (W/O) high internal phase emulsions (HIPEs) containing water, squalane oil and cetyl dimethicone copolyol was investigated with various compositional changes, such as electrolyte concentration, oil polarity and water phase volume fraction. The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The slope change of complex modulus versus water phase volume fraction monitored in the linear viscoelastic region could be explained with the resistance to coalescence of the deformed interfacial film of water droplets in concentrated W/O emulsions: the greater the increase of complex modulus was, the more the coalescence occurred and the less consistent the emulsions were. Emulsion stability was dependent on the addition of electrolyte to the water phase. Increasing the electrolyte concentration increased the refractive index of the water phase, and thus decreased the refractive index difference between oil and water phases. This decreased the attractive force between water droplets, which resulted in reducing the coalescence of droplets and increasing the stability of emulsions. Increasing the oil polarity tended to increase emulsion consistency, but did not show clear difference in cream hardness among the emulsions.

A Study of stability in ratings for clothing styles (의복스타일에 따른 평가의 재현성 차이에 관한 연구)

  • 유경숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.27 no.8
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    • pp.924-934
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    • 2003
  • The aim of the present study was to measure intra-individual consistency in clothing style evaluation and to examine its relation to the ratings. For this study, a pilot test was conducted to 50 clothing majored university students to explore the stimulus of‘cute’,‘casual’,‘sexy’,‘elegant’,‘intelligent’,‘formal’,‘romantic’,‘individual’,‘refined’for the 9 each image styles from the 32 spring wears in fashion magazine$\boxDr$FARBE$\boxUl$(March, 2000). On the basis of the preliminary survey, the question items explored the 15 pairs of bipolar adjectives as seven-point Likert type. The main survey was preceded 94 female and 111 men of university students from March 13 to 24 in 2000, twice for 7-days interval. As a result of analyzing of correlation coefficients between the two ratings for each subjects, intra-individual consistency in the evaluation, ranged from -.11 to .87 and mean coefficient was .64 of female and .20 to .76 and mean coefficient was .57 of male. Female had higher intra-individual consistency in the evaluation than male. Based on the coefficients, the subjects were classified into three groups: high, medium, and low intra-individual consistency. Analysis of variance of mean ratings by the three groups revealed that significant difference existed in 42% of female and 25% of male in 135 combinations of 9 clothing and 15 semantic differential scales. There was an apparent tendency that subjects of female with high intra-individual consistency were mostly definitely to evaluate clothing, whereas the ones with low were least. But male shows opposit trend compare to each groups of female. The result of this study, it was found that female rated higher intra-individual consistency and definition in the two times evaluations than male and among the semantic differential scales'consistency differ depending on style and gender. It is believed that the result of this study is helpful clothing image evaluation, and clothing image selection tendency.

PSEUDOSPECTRAL METHOD FOR THE DAMPED BOUSSINESQ EQUATION

  • Choo, S.M.
    • Communications of the Korean Mathematical Society
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    • v.13 no.4
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    • pp.889-901
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    • 1998
  • Numerical approximations by pseudospectral method are obtained for the damped Boussinesq equation which is a modification of the good Boussinesq equation. The consistency and stability of the method are obtained using the extended Lax-Richtmyer equivalence theorem, which imply the convergence of the method. We obtain error estimates of O(h$^{s}$ + k$^2$) for a fully discrete pseudospectral method.

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Study on the Evaluation of Stability of Gel Structured Cosmetics

  • Park, Chan-Ik;Kim, Ki-Sun;Lee, Sung-Jun;Yoon, Myeong-Suk;Kang, Seh-Hoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.22 no.2
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    • pp.167-173
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    • 1996
  • The stability of gel structured emulsion and the effect of polyols on it have been studied by rheological property and interfacial tension. In this paper, three types of gel structured emulsions were prepared by using three polyols respectively(glycerine for sample 1, 1.3 BG for sample 2, PG for sample 3). And both complex modulus($G^*$) and loss angle[$\delta$ = tan-1(G"/G')] of samples were investigated against oscillating shear stress and frequency($\omega$). The results show sample 1 is most highly consistent with oscillating shear stress. And the results were compared with those of accelerated tests concerning storage stability of gel structured emulsion. To correlate consistency of rheological property with storage stability, interfacial tension from which adsorption efficiency of surfactant(Octyldodecyl Ether) could be known was measured. Sample 1 showed the largest value of [$d{\gamma}/dIn_{Cconc. of surfactant}$] in Gibbs equation. In summary, the prediction of stability could be correctly made by the consistency of rheological property(G*,$\gamma$) of gel structured emulsion against oscillating shear stress and it could be supported by measuring interfacial tension. And polyol affected the value of [$d{\gamma}/dIn_{Cconc. of surfactant}$], consequently affected the stability.lity.

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