• 제목/요약/키워드: Coefficient $\beta$

검색결과 675건 처리시간 0.029초

$OMP-{\beta}-CD$ 포접화합물의 물리화학적 성질, 안정성 및 피부 투과 실험 (Study of the Percutaneous Absorption, Stability and Physicochemical Properties of $OMP-{\beta}-CD$ Inclusion Complex)

  • 이상영;이계원;최현순;지웅길
    • Journal of Pharmaceutical Investigation
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    • 제27권4호
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    • pp.271-277
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    • 1997
  • Because omeprazole(OMP) is very unstable in aqueous condition, $OMP-{\beta}-CD$, the inclusion complex of OMP and ${\beta}-cyclodextrin({\beta}-CD)$ was made and physicochemical properties of it were compared with those of OMP. Skin permeability of OMP and $OMP-{\beta}-CD$ in propylene glycol vehicle and the reciprocal action of ${\beta}-CD$ with various enhancers were examined through hairless mouse. Adhesive patches were prepared with polyisobutylene and the skin permeability and stability of OMP were investigated. The inclusion complex showed higher solubility and lower partition coefficient than OMP itself. DMSO, 1-methyl 2-pyrrolidone and sodium cholate had an enhancing effect. However ethanol and polysorbate 80 hardly showed the enhancing effect of OMP. When sodium lauryl sulfate and sodium cholate as enhancer were added in patch, the former case showed higher permeability of OMP.

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Mixing Rules of Young's Modulus, Thermal Expansion Coefficient and Thermal Conductivity of Solid Material with Particulate Inclusion

  • Hirata, Yoshihiro;Shimonosono, Taro
    • 한국세라믹학회지
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    • 제53권1호
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    • pp.43-49
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    • 2016
  • This analyzed a Young's modulus (E), a thermal expansion coefficient (TEC, ${\beta}$) and a thermal conductivity (${\kappa}$) of the material with simple cubic particulate inclusion using two model structures: a parallel structure and a series structure of laminated layers. The derived ${\beta}$ equations were applied to calculate the ${\beta}$ value of the W-MgO system. The accuracy was higher for the series model structure than for the parallel model structure. Young's moduli ($E_c$) of sintered porous alumina compacts were theoretically related to the development of neck growth of grain boundary between sintered two particles and expressed as a function of porosity. The series structure model with cubic pores explained well the increased tendency of $E_c$ with neck growth rather than the parallel structure model. The thermal conductivity of the three phase system of alumina-mullite-pore was calculated by a theoretical equation developed in this research group, and compared with the experimental results. The pores in the sintered composite were treated as one phase. The measured thermal conductivity of the composite with 0.5-25% porosity (open and closed pores) was in accordance with the theoretical prediction based on the parallel structure model.

Development of Lactose-hydrolyzed Milk with Low Sweetness Using Nanofiltration

  • Choi, S.H.;Lee, S.-B.;Won, H.-R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권6호
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    • pp.989-993
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    • 2007
  • A lactose-hydrolyzed milk with low sweetness was developed using nanofiltration. Raw milk was treated with 0.03% ${\beta}$-galactosidase at $4^{\circ}C$ for 24 h to hydrolyze lactose partially. The resultant lactose-hydrolyzed milk containing 0.43% lactose was then concentrated using a nanofiltration membrane to reach concentration factor of 2.13. The concentration factors and coefficients of retention of milk components in nanofiltration were determined. The concentration factor of milk fat was 2.20 which was the highest of the milk components. The coefficient of retention of calcium and riboflavin was 0.96 and 0.76, respectively. However, the coefficient of retention of glucose, galactose, and sodium was 0.21, 0.15, and 0.22, respectively. Raw milk was treated with 0.1% ${\beta}$-galactosidase at $4^{\circ}C$ for 40 h to hydrolyze lactose fully and then concentrated to reach a concentration factor of 1.6 by using nanofiltration. The concentrated milk was reconstituted with water. The lactose-hydrolyzed milk had sweetness similar to milk. The compositional ratios of crude protein, calcium, sodium, and riboflavin of lactose-hydrolyzed nanofiltrated milk to those of raw milk were 99%, 97%, 77%, and 80%, respectively. This study showed that nanofiltration of lactose-hydrolyzed milk to remove galactose and glucose did not cause significant loss of calcium. The lactose-hydrolyzed nanofiltrated milk contained 0.06% lactose and had sweetness similar to milk.

Comparison of Three Binomial-related Models in the Estimation of Correlations

  • Moon, Myung-Sang
    • Communications for Statistical Applications and Methods
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    • 제10권2호
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    • pp.585-594
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    • 2003
  • It has been generally recognized that conventional binomial or Poisson model provides poor fits to the actual correlated binary data due to the extra-binomial variation. A number of generalized statistical models have been proposed to account for this additional variation. Among them, beta-binomial, correlated-binomial, and modified-binomial models are binomial-related models which are frequently used in modeling the sum of n correlated binary data. In many situations, it is reasonable to assume that n correlated binary data are exchangeable, which is a special case of correlated binary data. The sum of n exchangeable correlated binary data is modeled relatively well when the above three binomial-related models are applied. But the estimation results of correlation coefficient turn to be quite different. Hence, it is important to identify which model provides better estimates of model parameters(success probability, correlation coefficient). For this purpose, a small-scale simulation study is performed to compare the behavior of above three models.

부문항이 분할된 고사에서 우량한 신뢰도 계수추경과 그 평가치 분포의 정규화 (On Estimating Good Reliability Coefficient when the Test is Split into Several Formats of Subtests and Standardizing the Raw Score, whose Distribution is Departed from Normality.)

  • 홍석강
    • 한국수학교육학회지시리즈A:수학교육
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    • 제41권1호
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    • pp.109-126
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    • 2002
  • In this thesis. we estimated the good reliability coefficient ${\beta}$$\sub$k/ that is unbiased, consistent and more efficient than Cronbach's ${\alpha}$$\sub$k/ in splitting of a test into several formats of subtests and several properties of ${\beta}$$\sub$k/ are also represented. The tables of coefficients of skewness and kurtosis are represented to test the significance of departures from normality. We got the cumulative normal plots of z'from the distribution which is departed from normality using the Bock's approximation procedure and we finally enumerated the transformed standardized scores z'and a new raw score X' which enable us to proceed further evaluation procedures depending on our assessment policy.

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A Sediment Concentration Distribution Based on a Revised Prandtl's Mixing Theory

  • Jung, Kwan-Sue
    • Korean Journal of Hydrosciences
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    • 제8권
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    • pp.1-17
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    • 1997
  • Prandtl's mixing length theory was modified to obtain a power velocity distribution in which the coefficient and the exponent are variable over a range from : $$ A simple suspended-sediment concentration distribution was developed from the modified velocity distribytion : $ With nominal values of $\beta$=1.0, $\kappa$=0.4 and visual accumulation tube values of the fall velocity, the comparison between the theory and field measurements by the USGS on the Rio Grande is fair. Doubling the value of the exponent results in a good comparison. Further researches are needed for choosing the values of $\beta$, $\kappa$, and fall velocity values, and consideration on the effects of large-scale turbulence and secondary flows are necessary for them. In a pragmatic sense, on any gaging sites the close analysis of very detailed measurements can establish its specific coefficient and exponent.

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기계적 합금화로 제조된 Fe0.92Mn0.08Si2의 상변화 및 열전 특성 (Phase Transformation and Thermoelectric Properties of Fe0.92Mn0.08Si2 Prepared by Mechanical Alloying)

  • 김영섭;조경원;김일호;어순철;이영근
    • 한국재료학회지
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    • 제13권5호
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    • pp.292-296
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    • 2003
  • In an attempt to enhance phase transformation and homogenization of Mn-doped $FeSi_2$, mechanical alloying of elemental powders was applied. Cold pressing and sintering in vacuum were carried out to produce a dense microstructure, and then isothermal annealing was employed to induce a phase transformation to the $\beta$-$FeSi_2$semiconductor. Phase transitions in this alloy system during the process were investigated by using XRD, EDS and SEM. As-milled powders after 100 h of milling were shown to be metastable state. As-sintered iron silicides consisted of untransformed mixture of $\alpha$-$Fe_2$$Si_{5}$and $\varepsilon$-FeSi phases. $\beta$-$FeSi_2$phase transformation was induced by subsequent isothermal annealing at $830^{\circ}C$, and near single phase of $\beta$-$FeSi_2$was obtained after 24 h of annealing. Thermoelectric properties in terms of Seebeck coefficient, and electrical conductivity were evaluated and correlated with phase transformation. Seebeck coefficient electrical resistivity and hardness increased with increasing annealing time due to $\beta$ phase transformation.

노인의 구강건강 영향지수가 우울과 삶의 질에 미치는 영향 (Effects of Oral Health Impact Profile (OHIP) on Depression and Quality of Life among Community-dwelling Korean Elderly Persons)

  • 이홍자;김춘미
    • 지역사회간호학회지
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    • 제23권3호
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    • pp.338-346
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    • 2012
  • Purpose: The purpose of this study was to examine the association between oral health impact profile, depression and quality of life among community-dwelling elderly persons in South Korea. Methods: The design of this research was cross-sectional descriptive study. The participants were 266 community-dwelling individuals aged 65 and older. Data were collected from November 20 to December 20, 2011. The measurements for assessing the subjects' oral health, depression, quality of life were OHIP-14, GDS-SF and QOL. Data were collected using self-administered or interviewer-administered questionnaires. Collected data were analyzed using descriptive statistics, Pearson's correlation coefficient and stepwise multiple regression. Results: The participants' mean age was 77.68, and 86.5% were female, 42.9% were living-alone elders. Pearson's correlation coefficient analysis found that oral health impact profile was significantly associated with depression (r=-.622, p<.001), QOL (r=-.400, p<.001), number of disease (r=.298, p<.001), age (r=.198, p=.002), education (r=-.149, p=.015), eating habit (r=.185, p=.003). The QOL was explained 54.7% by depression (${\beta}$=-.619), oral health impact profile (${\beta}$=-.127), number of benefited welfare service (${\beta}$=.235), perceived health (${\beta}$=-.327), eating habit (${\beta}$=-.094) using stepwise multiple regression analysis. Conclusion: These results indicate that the intervention program of oral health promotion for community-dwelling elders is needed from now on.

판상형 충전제의 함량과 배향에 따른 PP복합체의 열팽창계수 영향 연구 (Empirical Study on Effects of Disk Shape Filler Content and Orientation on Thermal Expansion Coefficient of PP Composites)

  • 이용현;정선경;황효연;이승구;이기윤
    • 폴리머
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    • 제36권3호
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    • pp.281-286
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    • 2012
  • 두 가지의 종횡비(${\rho}_{\alpha}=a_1/a_3$ and ${\rho}_{\beta}=a_1/a_2$)에 의해 특징지어진 3차원 타원체($a_1$ > $a_2$ > $a_3$)를 사용하여 polypropylene 복합체의 판상형 충전제 함량과 방향이 열팽창률에 미치는 영향에 대해 실험적인 연구를 수행하였다. 측정된 실험적인 값은 Lee와 그의 연구자들이 제안한 이론적인 모델에 의한 계산 값과 비교분석되었다. 판상형 충전제로는 운모와 탈크가 사용되었다. 실험 결과로 운모의 경우 종횡비는 ${\rho}_{\alpha}=13.5$, ${\rho}_{\beta}=1.8$이 사용되어, 20 wt% 함량일 때 ${\alpha}_{11}/{\alpha}_m$는 약 0.56으로 감소하였으나, ${\alpha}_{33}/{\alpha}_m$는 오히려 1.018로 증가함을 보였다. 탈크의 경우의 종횡비는 ${\rho}_{\alpha}=3.7$, ${\rho}_{\beta}=1.4$이었고 ${\alpha}_{11}/{\alpha}_m$는 0.63으로 감소하였다. 결국 운모와 탈크 모두 그 함량증가에 따라 종단방향과 횡단방향에서 열팽창률은 감소하였으나 수직방향에서는 초기 낮은 충전제 함량에서는 오히려 증가하는 경향을 보였다.

응급구조학과 학생들의 결핵에 대한 지식 및 태도가 결핵감염 예방행위에 미치는 영향 (The Effect of Department of Emergency Medical Service Students' Knowledge and Attitudes toward Tuberculosis Infection Prevention Behaviors)

  • 문성모;김덕원
    • 한국산학기술학회논문지
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    • 제20권2호
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    • pp.259-266
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    • 2019
  • 본 연구는 응급구조학과 학생들의 결핵에 대한 예방행위에 미치는 요인을 파악하고 응급구조학과 학생들의 결핵에 대한 예방행위수준을 높이기 위하여 조사하였다. 전라북도의 4년제 대학 1개와 3년제 대학 2개의 응급구조학과 학생 314명을 대상으로 2018년 6월 25일부터 7월 6일까지 12일간 설문조사를 실시하였다. 통계분석은 SPSS 18.0 프로그램을 사용하였으며, t-test, ANOVA, pearson correlation coefficient, 다중회귀분석으로 분석하였다. 상관분석 결과 결핵에 대한 예방행위는 결핵에 대한 지식(r=0.268, p<0.001)과 태도(r=0.394, p<0.001)에 모두 유의한 양의 상관관계를 나타냈다. 다중회귀분석 결과 결핵에 대한 지식이 높을수록(${\beta}=0.152$, p<0.001), 태도가 높을수록(${\beta}=0.052$, p<0.001) 예방행위수준이 높아지는 것으로 나타났다. 또한 본인 또는 친인척이 결핵 발병을 경험한 학생들의 예방행위수준이 높았다(${\beta}=-0.186$, p=0.001). 따라서 응급구조학과 학생들에게 결핵에 대한 지식수준을 높이고 부정적인 인식과 태도를 변화시켜 예방행위 수준을 향상시킬 수 있는 체계적이고 지속적인 생활화된 교육이 필요하다.