• 제목/요약/키워드: k/s values

검색결과 11,524건 처리시간 0.037초

n-부탄올 및 NaCl 수용액에서 양이온 계면활성제인 TTAB에 의한 크레졸 이성질체들의 가용화에 대한 연구 (Solubilization of Cresol Isomers by the Cationic Surfactant of TTTAB in Aqueous Solution of n-Butanol and NaCl)

  • 이병환
    • 한국응용과학기술학회지
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    • 제38권3호
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    • pp.832-839
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    • 2021
  • 양이온 계면활성제인 tetradecyltrimethylammonium bromide (TTAB)에 의한 크레졸 이성질체의 가용화에 미치는 치환기, 온도 그리고 NaCl과 n-부탄올과 같은 첨가제의 효과를 UV-Vis법으로 측정하였다. 가용화상수(Ks)값은 o-크레졸s값은 감소하였다. 크레졸 이성질체들의 가용화에 대하여 계산한 ∆Go값과 ∆Ho값은 모두 음의 값을 나타내었다. 그러나 ∆So값은 모두 양의 값을 나타내었다. 또한 ∆Go값은 n-부탄올의 농도가 증가할수록 증가하는 경향을 그러나 NaCl의 농도가 증가할수록 더욱 감소하는 경향을 보였다. 이러한 사실들로부터 크레졸 이성질체들의 가용화에는 엔탈피와 엔트로피가 동시에 기여하고 있으며, 또한 크레졸분자들이 가용화되는 위치는 미셀의 표면이나 palisade층에서 주로 이루어짐을 알 수 있다.

신경회로망을 이용한 DC-DC 컨버터의 출력전압제어 (Neural network controller based approach to the output voltage control of DC-DC converter)

  • 황계호;김동희;남승식;배상준;이봉섭;심광열;안항목
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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    • pp.89-92
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    • 2003
  • Recently, Research that output voltage control using several control methods to dc-dc converter that is non-linear system is gone. This paper describes control algorithm of the Buck type DC-DC converter using neural network controller We conform a rightness theoretical analysis by comparing a theoretical values, simulation values obtained from simulation tool and experimental values obtained from experiment. the neural network controller got better special characteristic than the hysteresis controller, This paper is thought to be applied to several power conversion system use neural network controller.

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부가응력과 반발경도와의 관계 (The Relation between Applied Stress and Rebound Hardness Values)

  • 남승훈;김시천;전승범
    • 열처리공학회지
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    • 제8권4호
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    • pp.318-325
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    • 1995
  • Information of change of hardness values during applying load is needed often to control the quality of metal products efficiently, but the relation between applied stress and hardness has not been established. In this paper the theoretical relation between the rebound hardness and stress was examined briefly and the experiment was performed with some materials. Materials used in test were mild steel(SB41), 7-3 brass and copper, which were widely used in the commercial plants. Hardness was measured during stress applied using the Equo-Tip hardness tester as a kind of rebound hardness tester. Hardness values decreased as tensile stress increased, the decreasing rate was effected by the Young's modulus of each material, and the rebound hardness values showed linear relationship with the applied stress in elastic region.

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Bioelectrical Impedance Analysis를 통한 건강한 성인과 TPN환자의 기초대사량 산출 (Assessment of Basal Energy Expenditure in Normal Healthy Volunteers and Patients Receiving TPN by Bioelectrical Impedance Analysis)

  • 손은선;김충배;서옥경;신현택;이숙향
    • 한국임상약학회지
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    • 제9권1호
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    • pp.19-26
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    • 1999
  • Adequate nutrition is important in maintaining optimal health. Malnutrition can expose individual to increased risks of morbidity and mortality. The purposes of this study were to determine the basal energy expenditure (BEE) of Korean healthy subjects and TPN patients using Bioelectrical Impedance Analysis (BIA) method and to compare these values with those predicted by Harris-Benedict equation (H-B). BEE values measured by BIA were compared with predicted BEE values by the H-B formula in 59 clinically stable TPN patients and 65 healthy volunteers. In healthy volunteers and TPN patients, statistically significant differences were not shown between the BEE values measured by BIA (1392.5 Kcal and 1325.9 Kcal) and those predicted by H-B formula (1384.1 Kcal and 1270.1 Kcal). In male volunteers, statistically significant differences were not shown between BEE values measured by BIA (1670.7 Kcal) and the H-B formula (1550.9 Kcal), but in female volunteers, statistically significant differences were shown between BEE values measured by BIA (1194.8 Kcal) and the H-B formula (1265.6 Kcal). In male TPN patients, statistically significant differences were shown between BEE values measured by BIA (1453.5 Kcal) and the H-B formula (1335.9 Kcal), but in female TPN patients, statistically significant differences were not shown between BEE values measured by BIA (1126.4 Kcal) and the H-B formula (1167.2 Kcal). In normal healthy volunteers, $90.8\%$ of BEE values measured by BIA and in TPN patients $89.8\%$ of BEE values measured by BIA were within $15\%$ of BEE values predicted by the H-B formula in non-obese subjects. In conclusion, BEE values predicted by H-B formula or measured by BIA can be applied to non-obese Koreans. However, these values should be confirmed with Indirect calorimetry for Koreans.

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Correlation of the Rates of Solvolysis of Electron-Rich Benzoyl Chloride Using the Extended Grunwald-Wistein Equation

  • Oh, Hyunjung;Choi, Hojune;Park, Jong Keun;Yang, Kiyull;Koo, In Sun
    • Bulletin of the Korean Chemical Society
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    • 제34권9호
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    • pp.2697-2701
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    • 2013
  • The solvolysis rate constants of piperonyloyl chloride (1) in 27 different solvents are well correlated with the extended Grunwald-Winstein equation, using the $N_T$ solvent nucleophilicity scale, $Y_{Cl}$ solvent ionizing scale, and I aromatic ring parameter with sensitivity values of $0.30{\pm}0.05$, $0.71{\pm}0.02$, and $0.60{\pm}0.04$ for l, m, and h, respectively. The solvent kinetic isotope effect values (SKIE, $k_{MeOH}/k_{MeOD}$ and $k_{50%MeOD-50%D2O}$) of 1.16 and 1.12 were also in accord with the values for the $S_N1$ mechanism and/or the dissociative $S_N2$ mechanism. The product selectivity values (S) for solvolysis of 1 in alcohol/water mixtures were in the range of 0.5 to 1.9, which is also consistent with the proposed unimolecular ionization mechanism.

2030대와 4050대 남성소비자들의 외모관리 기대가치가 남성정장 구매행동에 미치는 영향 (The Expected Values of Appearance Management of 20s-30s and 40s-50s Male Consumers on their Men's Suit Buying Behaviors)

  • 정혜정;이유리
    • 한국의류학회지
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    • 제35권2호
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    • pp.125-135
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    • 2011
  • This study compares the expected values of appearance management for the suit buying behavior of men in two age groups: (20s-30s and 40s-50s) to investigate the effect of male consumers' expected values in regards to appearance management on the purchase behavior of men's suits between two generations. A survey was carried out with male consumers between the ages of 20 and 50; a total of 135 responses were analyzed by descriptive analysis, factor analysis, a reliability test, an independent samples t-test, MANOVA, ANOVA, and regression analysis. The results of this study were as follows: 1) From a result of the factor analysis on male consumers' expected value of appearance management and the information sources and purchase evaluative criteria for buying men's suits, each of three variance assessments clearly showed factorial structures. 2) There were significant differences between those in their 20s-30s and those in their 40s-50s in terms of male consumers' expected values of appearance management, their information sources, and their purchase evaluative criteria when buying men's suits. 3) As a result of looking at the differences in the effects of expected values of appearance management on men's suit buying behavior according to age (generation), the younger generation in this study showed that men's suit purchasing tendency was affected by the managing appearance factor for internal reasons such as enjoyment and self-satisfaction. On the other hand, the assessment of the older generation revealed that appearance management for external reasons such as showing social power, good human relationships, and conformity influenced their suit purchase behaviors.

Socioeconomic Changes and Value Modernization in China: Changes and Continuity 1993-2011

  • Wang, Zhengxu
    • Asian Journal for Public Opinion Research
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    • 제2권3호
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    • pp.140-171
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    • 2015
  • As China's economic development brings the country out of poverty and into modernity, a long-lasting debate concerns whether the Chinese public's value system is also changing toward the so-called "modern values," or whether some distinctly traditional Chinese values remain unchanged. Using empirical data collected at three points in time during the 1990s and the first two decades of the 21st Century (1993, 2002, and 2011), I found that Chinese citizens who benefitted from urbanization, rising levels of education and employment in non-farm, knowledge-based industries displayed stronger modern values. People with stronger modern values are more likely to emphasize individual autonomy, competition, gender equality, and market transaction, among others. Some characteristics of the Chinese people, most importantly family values, however, seem to remain stable amidst rapid social changes.

아시안 에스닉 룩의 조형성과 미적가치에 판한 연구 (The Research of Visual and Aesthetic Values of an Asian Ethnic Look)

  • 권하진;김민자
    • 복식
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    • 제56권6호
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    • pp.114-131
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    • 2006
  • An Asian Ethnic Look is based on its own values of traditional costumes and the fashion accessories that are influenced by its own genre within their own culture. In this thesis, it contemplates the study of visual values and the traditional influences of the Modern Western Designers and Asian Designers' definitions and the considerations of an Ethnic look in the countries like Middle East, India, Korea, China and Japan. The standard procedure to understand their Visual and Aesthetic values is acknowledgement of body. From that foundation, an Asian Ethnic Look and its Visual and Aesthetic Values were researched through out the Middle East Asian Look, Indian Look, Korean Look, Chinese Look and Japanese Look which effective after 1990's. The studies are further researched to the comparisons and interpretations of the Western Designers and the Asian Designers, and the definitions of an Asian Ethnic Look and its Visual and Aesthetic Values in between those. According to each country's religious attitudes, a beauty of concealment and a beauty of negative space appeal which emphasize an ethics on humanity and non-materialistic attitudes. It takes meanings of a phenomenon of nature's worship, Yin-Yang five elements of principles, oneness of body-mind and oneness of universe-mankind. Following the studies of Visual and Aesthetic Values of an Asian Ethnic Look, in 1990's Western Designers' interpretations were prominent use of the Asian Traditional Motif3. However, the interpretations of the Asian Designers were based on their own traditional ethics and they minimized decorative elements but enhanced naturalism, feminism, calm and sober designs compare to the past. The Asian Designers' interpretations of their visual values were based on their Asian mentality, beauty and its straightforward genuine perspective and respects of their own culture.

계절(季節)에 따른 헤어컬러 변화(變化)에 관(關)한 연구(硏究) - 2003 $\sim$ 6년 여성잡지(女性雜誌)에 나타난 헤어컬러 트렌드를 중심(中心)으로- (A Study on the Seasonal Changes of Hair Color - Centered on 2003 $\sim$ 6' hair color trends published on women's magazines -)

  • 안현경
    • 패션비즈니스
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    • 제11권1호
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    • pp.1-14
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    • 2007
  • This study was aimed at giving help to the people intending to change their own hair color design and also providing the guide line to the cosmetic circles for developing new hair color design and promoting sales by statistically analyzing seasonal changes of hair colors puplished on women's magazines(Vogue Korea, Estetica Korea, Woman Chosun, Ce.ci) from 2003 to 2006. The researching methods were as follows; (1) hair colors published on women's magazines from september 2003 to August 2006 were measured by N.C.S. color reader(4 magazines $\times$10 main hair colors/magazine $\times$ 12 months $\times$ 3 years = 1,440 colors). (2) N.C.S. tone is made of percentage, so measured values and chromas were statistically analyzed by mean, standard deviation, and seasonal deferences were statistically analyzed by t-test and specified on high significant values. But hues were not made of percentage, so these were statistically analyzed by cross tabulation analysis, $x^2$ -test and specified on high significant values. These all had been analyzed by SPSS program(ver. 11.0). The results were as follows; (1) Usually seasonal changes of hair values were significant, specially in foreign licensed magazines, and bright values appeared in S/S and dark values in F/W. (2) Seasonal changes of hair hues were significant only on foreign women's magazines. Therefore seasonal changes of korean hair colors were not significant compared by foreign hair colors because of hardness of color changes of dark black hair and hair damages by hair tints and bleaches and trends of well being and hair care. But hair color changes have been developed gradually and will developed furthermore. So korean hair cosmetic circles have to present hair color trends deferenciated by seasons. And S/S hair values have to be brignt and F/W have to be dark. And new seasonal hair hues matched by korean have to be developed and presented.