• 제목/요약/키워드: Mixed-effect

검색결과 4,841건 처리시간 0.034초

PVC의 저온 열안정성 향상에 관한 연구 (Improvement of low temperature thermal stability on PVC)

  • 정광보;전인기;안성환
    • 한국응용과학기술학회지
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    • 제26권4호
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    • pp.440-450
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    • 2009
  • Metal(Zinc) soap and mixed metal(Zn/Ba) soap were synthesized with good structures and characterized by IR and H-NMR. The H-NMR spectrums of the synthesized soaps were in very good accordance with the structures proposed by earlier workers. The mixed metal soaps with various costabilizers(acid or metal content effect), which added in order to investigate the thermal stabilization effect at low and high temperature, were investigated the thermal stabilization effect. The temperature effect is relation to the metal content effect than acid effect. In case of mixed metal soap, the high thermal stabilization effect improved with increasing Barium content. As the Zinc content increase the low temperature thermal stabilization effect improved, but the high temperature thermal stabilization effect showed an opposite tendency.

ZrO2의 혼합방법 차이가 ZTA의 기계적 물성에 미치는 영향 (Effect of Difference in Mixing Methods of Zirconia on Mechanical Properties of ZTA)

  • 손정호
    • 한국재료학회지
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    • 제23권11호
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    • pp.625-630
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    • 2013
  • In this study, intermediate-mixed powders were prepared by loading zirconia powders initially in a ball-mill jar and loading alumina powders afterward; the initial-mixed powders were produced by loading zirconia and alumina powders together in the ball-mill jar. The effect of such differences in mixing method on the mechanical properties was investigated. In intermediate-mixed powders, the volume fraction of large particles slightly increased and, simultaneously, zirconia particles formed agglomerates that, due to early ball-mill loading of the zirconia powders only, were more dispersed than were the initial-mixed powders. For the intermediate-mixed powders, zirconia agglomerates were destroyed more quickly than were initial-mixed powders, so the number of dispersed zirconia particles rose and the inhibitory effect of densification due to the addition of a second phase was more obvious. In the microstructure of intermediate-mixed powders, zirconia grains were homogeneously dispersed and grain growth by coalescence was found to occur with increasing sintering temperature. For the initial-mixed powders, large zirconia grains formed by localized early-densification on the inside contacts of some zirconia agglomerates were observed in the early stages of sintering. The intermediate-mixed powders had slightly lower hardness values as a whole but higher fracture toughness compared to that of the initial-mixed powders.

혼합효과모형의 리뷰 (Review of Mixed-Effect Models)

  • 이영조
    • 응용통계연구
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    • 제28권2호
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    • pp.123-136
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    • 2015
  • 관측 가능한 변수들 사이의 관계를 묘사한 갈릴레오의 물리학 법칙 발견 이후, 과학은 큰 성과를 거두며 발전해왔다. 그러나, 관측할 수 없는 변량효과를 함께 이용하여 더 많은 자연 현상을 설명할 수 있게 되었고, 이를 이용한 최초의 통계적 모형인 혼합효과모형이 소개되었다. 계산기술의 발달과 더불어 복잡한 현상에 대한 추론을 위하여 혼합효과모형은 그 중요성이 더욱 커지고 있다. 이러한 혼합효과모형은 최근 다단계 일반화 선형모형을 포함한 여러 모형으로 확장되었으며, 관측할 수 없는 변량효과를 추론하기 위한 다단계 가능도가 제시되었다. 혼합효과모형 특집호를 통해 이러한 모형들이 여러 통계학적 문제점을 해결하는 과정을 제시하고, 앞으로 어떤 확장이 추가적으로 요구되는 지에 대하여 논할 것이다. 빈도록적 접근법과 베이지안 접근법을 함께 다룬다.

The effect of an EML sequence and an interlayer on the performance of the phosphorescent-fluorescent mixed WOLEDs

  • Baek, Heume-Il;Lee, Chang-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1215-1218
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    • 2008
  • We investigate the effect of a light emitting layer (EML) sequence and an interlayer on the performance of the phosphorescent-fluorescent mixed white organic light emitting diodes. Two types of phosphorescent-fluorescent mixed system were evaluated. The proper position of each primary color EML was crucial to obtain best performance in each system whereas the effect of an interlayer was found to be different in both systems.

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Statistical Method for Implementing the Experimenter Effect in the Analysis of Gene Expression Data

  • Kim, In-Young;Rha, Sun-Young;Kim, Byung-Soo
    • Communications for Statistical Applications and Methods
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    • 제13권3호
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    • pp.701-718
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    • 2006
  • In cancer microarray experiments, the experimenter or patient which is nested in each experimenter often shows quite heterogeneous error variability, which should be estimated for identifying a source of variation. Our study describes a Bayesian method which utilizes clinical information for identifying a set of DE genes for the class of subtypes as well as assesses and examines the experimenter effect and patient effect which is nested in each experimenter as a source of variation. We propose a Bayesian multilevel mixed effect model based on analysis of covariance (ANACOVA). The Bayesian multilevel mixed effect model is a combination of the multilevel mixed effect model and the Bayesian hierarchical model, which provides a flexible way of defining a suitable correlation structure among genes.

Mixed-effects LS-SVR for longitudinal dat

  • Cho, Dae-Hyeon
    • Journal of the Korean Data and Information Science Society
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    • 제21권2호
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    • pp.363-369
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    • 2010
  • In this paper we propose a mixed-effects least squares support vector regression (LS-SVR) for longitudinal data. We add a random-effect term in the optimization function of LS-SVR to take random effects into LS-SVR for analyzing longitudinal data. We also present the model selection method that employs generalized cross validation function for choosing the hyper-parameters which affect the performance of the mixed-effects LS-SVR. A simulated example is provided to indicate the usefulness of mixed-effect method for analyzing longitudinal data.

수직 동심 환형관 내의 난류혼합대류 현상에 관한 직접수치모사 (Direct Numerical Simulation of Turbulent Mixed Convection in Heated Vertical Annulus)

  • 전용준;배중헌;유정열
    • 대한기계학회논문집B
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    • 제33권9호
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    • pp.674-681
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    • 2009
  • Turbulent mixed convection in heated vertical annulus is investigated using Direct Numerical Simulation (DNS) technique. The objective of this study is to find out the effect of buoyancy on turbulent mixed convection in heated vertical annulus. Downward and upward flows with bulk Reynolds number 8500, based on hydraulic diameter and mean velocity, have been simulated to investigate turbulent mixed convection by gradually increasing the effect of buoyancy. With increased heat flux, heat transfer coefficient first decreases and then increases in the upward flow due to the effect of buoyancy, but it gradually increases in downward flow. The mean velocity and temperature profiles can not be explained by the wall log laws due to the effect of buoyancy, too. All simulation results are in good quantitative agreement with existing numerical results and in good qualitative agreement with existing experimental results.

수직 동심 환형관 내의 난류혼합대류 현상에 관한 직접수치모사 (Direct numerical simulation of turbulent mixed convection in heated vertical annulus)

  • 전용준;배중헌;유정열
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2759-2764
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    • 2008
  • Turbulent mixed convection in heated vertical annulus is investigated using Direct Numerical Simulation (DNS) technique. The objective of this study is to find out the effect of buoyancy on turbulent mixed convection in heated vertical annulus. Downward and upward flows with bulk Reynolds number 8500, based on hydraulic diameter and mean velocity, have been simulated to investigate turbulent mixed convection by gradually increasing the effect of buoyancy. With increased heat flux, heat transfer coefficient first decreases and then increases in the upward flow due to the effect of buoyancy, but it gradually increases in downward flow. The mean velocity and temperature profiles can not be explained by the wall log laws due to the effect of buoyancy, too. All simulation results are in good quantitative agreement with existing numerical results and in good qualitative agreement with existing experimental results.

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고지방식에 혼합단백질과 L-카르니틴을 첨가했을 때 흰쥐의 지질대사에 미치는 영향 (Effects of Dietary Mixed Protein and L-Carnitine Supplementation on Lipid Metabolism in Rats fed High Fat Diet)

  • 원향례;김민선;이승교
    • 한국지역사회생활과학회지
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    • 제15권4호
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    • pp.89-96
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    • 2004
  • This study is to investigate the effect of dietary mixed protein and L-carnitine supplementation on lipid metabolism in the rats fed high fat diet. Six experimental groups were organized and each group had eight Sprague-Dawley male white rats with the initial weight of around 180g. The six experimental groups were CO(supplemented with casein), CC(supplementedwith casein and cartinine), ISO(supplemented with isolated soy protein), ISC(supplemented with isolated soy protein and cartinine), CIM(supplemented with casein and isolated soy protein), and CIC(supplemented with casein, isolated soy protein and cartinine). Each group was supplemented with the experimental diet for four weeks, and carnitine contained 3efo of the diet. The results were as follows; 1. There was no significant difference in food intake among the experimental groups. The weight increased more significantly in the group supplemented with the mixed protein than in the group supplemented with casein(p<0.05).2. There was weight reduction effect by the supplementation of carnitine(p<0.05), however no weight reduction effect by the supplementation of carnitine was observed in the group supplemented with the mixed protein and isolated soy protein. 3. Food efficiency was lower in the group supplemented with the mixed protein than in the group supplemented with casein (p<0.05), however it was similar in the group supplemented with isolated soy protein.4. Serum total lipid and se겨m total cholesterol were lower in the group supplemented with mixed protein than in the group supplemented with casein(p<0.05). 5. There was no significant difference of serum triglyceride, HDL-cholesterol, and LDL-cholesterol among the experimental groups. 6. Liver triglyceride was the highest in the group supplemented with mixed protein (p<0.05), and there was no significant difference of liver total lipid and total cholesterol among the experimental groups. 7. In the groups supplemented with mixed protein, the level of liver TBARS showed the lowest when casein was supplemented(p<0.05), and there was no significant difference of GSH-Px activities among the experimental groups. In summary, when mixed protein was supplemented to the rats weight gain and food efficiency were similar with those in the group supplemented with isolated soy protein, however they were lower than those in the group supplemented with casein. The effect of carnitine on weight was not observed in the group supplemented with mixed protein and isolated soy protein, however it was observed in the group supplemented with casein. Serum Total lipid and total cholesterol were lower than those in the group supplemented with casein. Liver total triglyceride was high in the group supplemented with mixed protein, and the antioxidant effect was observed in the group supplemented with mixed protein.

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전단마찰시험에 의한 섬유혼합토와 지오그리드 사이의 마찰 특성 평가 (Friction Properties between Fiber-Mixed Soil and Geogrid by Shear Friction Tests)

  • 조삼덕;김진만;이광우;안주환
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.813-820
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    • 2003
  • The shear friction tests using large direct shear test units were performed to evaluate the friction properties of fiber-mixed soil. The used materials and test conditions were flowing. Soils : SM and ML; mixing fibers : three types of polypropylene fibers(net type 38mm and 60mm, and line type 60mm), reinforcement : geogrid; mixing ratio:0.2% and 0.3%; degree of compaction : 85% and 95%. In the test results, the reinforcing effect of fiber mixed soil was confirmed.

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