• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.1027-1039
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• 2005

Consider the problem of estimating a $p{\times}1$ mean vector $\theta(p\geq4)$ under the quadratic loss, based on a sample $X_1$, $X_2$, $\cdots$, $X_n$. We find a Lindley type decision rule which shrinks the usual one toward the mean of observations when the underlying distribution is that of a variance mixture of normals and when the norm $\parallel\;{\theta}-\bar{{\theta}}1\;{\parallel}$ is restricted to a known interval, where $bar{{\theta}}=\frac{1}{p}\;\sum\limits_{i=1}^{p}{\theta}_i$ and 1 is the column vector of ones. In this case, we characterize a minimal complete class within the class of Lindley type decision rules. We also characterize the subclass of Lindley type decision rules that dominate the sample mean.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.73-77
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• 2019

Isothermal (vapor + liquid) equilibrium data measurements were undertaken for the binary mixtures of (propylene oxide + 1-pentanol) system at three different temperatures (303.15, 318.15, and 333.15) K. The Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS) was used to correlate the experimental data. The van der Waals one-fluid mixing rule was used for the vapor phase and the Wong-Sandler mixing rule, which incorporates the non-random two liquid (NRTL) model, the universal quasi-chemical (UNIQUAC) model and the Wilson model, was used for the liquid phase. The experimental data were in good agreement with the correlation results.

• Journal of Integrative Natural Science
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• v.10 no.1
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• pp.33-39
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• 2017

Consider the problem of estimating a $p{\times}1$ mean vector ${\theta}(p-q{\geq}3)$, $q=rank(P_V)$ with a projection matrix $P_v$ under the quadratic loss, based on a sample $X_1$, $X_2$, ${\cdots}$, $X_n$. We find a James-Stein type decision rule which shrinks towards projection vector when the underlying distribution is that of a variance mixture of normals and when the norm ${\parallel}{\theta}-P_V{\theta}{\parallel}$ is restricted to a known interval, where $P_V$ is an idempotent and projection matrix and rank $(P_V)=q$. In this case, we characterize a minimal complete class within the class of James-Stein type decision rules. We also characterize the subclass of James-Stein type decision rules that dominate the sample mean.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.9
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• pp.663-670
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• 2020

A study on mechanical property characterization and modeling technique was carried out to approximate the behaviour of structures with 2.5D C/SiC material. Several tensile tests were performed to analyze the behaviour characteristics of the 2.5D C/SiC material and elastic property was characterized by applying a mathematical homogenization and a modified rule of mixture. SiC matrix representing the elasto-plastic behavior approximates as a bilinear function. Then the equivalent yield strength and equivalent plastic stiffness were calculated by minimizing errors in experiment and approximation. RVE(Representative Volume Element)was defined from the fiber and matrix configuration of 2.5D C/SiC and a process of calculating the effective stiffness matrix by applying the modified rule of mixture to RVE was implemented in the ABAQUS User-defined subroutine. Finite element analysis was performed by applying the mechanical properties of fiber and matrix calculated based on the proposed process, and the results were in good agreement with the experimental results.

• Computers and Concrete
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• v.22 no.2
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• pp.161-166
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• 2018

This paper deals with the instability analysis of concrete pipes conveying viscous fluid-nanoparticle mixture. The fluid is mixed by $AL_2O_3$ nanoparticles where the effective material properties of fluid are obtained by mixture rule. The applied force by the internal fluid is calculated by Navier-Stokes equation. The structure is simulated by classical cylindrical shell theory and using energy method and Hamilton's principle, the motion equations are derived. Based on Navier method, the critical fluid velocity of the structure is calculated and the effects of different parameters such as fluid velocity, volume percent of nanoparticle in fluid and geometrical parameters of the pipe are considered. The results present that with increasing the volume percent of nanoparticle in fluid, the critical fluid velocity increase.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.41-50
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• 1999

As for the properties on both the aluminum and the CFRP which are used to make A17075/CFRP multi-layered hybrid composites, CRALL(carbon reinforced aluminum laminate). In the CRALL specimen for rule of mixture, we were analyzed notched strength by finite element method. The results obtained from FEM analysis are as follows; In the unnotch CRALL specimen, the stresses CFRP, epoxy, Al 7075 obtained by finite element method strength solution for A/C0001, when strain is 0.28%, are 1400MPa, 38MPa, 411MPa. respectively and for A/C9991, when strain 0.48%, are 392MPa, 26MPa and 321Mpa, respectively. the solpe of the stress-strain curve by FEM increases in keeping with the hole size and the yield strain decrease to 36% and 55% for A/C9993 and A/C9991 respectively.

• Journal of Integrative Natural Science
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• v.6 no.4
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• pp.251-255
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• 2013

For the mean vector of a p-variate normal distribution ($p{\geq}4$), the optimal estimation within the class of modified James-Stein type decision rules under the quadratic loss is given when the underlying distribution is that of a variance mixture of normals and when the norm ${\parallel}{\theta}-\bar{\theta}1{\parallel}$ it known.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.180-183
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• 2001

Glass fiber reinforced plastic(CFHP) tent pole fabricated by the pultrusion process with unidirectional glass fiber is two times as heavy as aluminum tent pole owing to the low specific modulus The first objective of this research is the design the high strength and light weight tent pole compete with. the second is the develope glass fiber carbon fiber hybrid tent pole pultrusion process. the third is the evaluate the mechanical properties of the hybrid tent pole compare to these of the duralumin tent pole.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.10
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• pp.3361-3370
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• 1996

Micro-Macro approach is conducted for the mixture solidification to handle the closely linked phenomena of microscopic solute redistribution and macroscopic solidification behavior. For this purpose, present work combines the efficiency of mixture theory for macro part and the capability of microscopic analysis of two-phase model for micro part. The micro part of present study is verified by comparison with experiment of Al-4.9 mass% Cu alloy. The effect of back diffusion on the macroscopic variables such as temperature and liquid concentration, is appreciable. The effect, however, is considerable on the mixture concentration and eutectic fraction which are indices of macro and micro segregation, respectively. According to the diffusion time, the behavior near the cooling wall where relatively rapid solidification permits short solutal diffusion time, approaches Scheil equation limit and inner part approaches lever rule limit.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.637-640
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• 2005

The density of polar-nonpolar liquid mixtures composed of methyl tert-butyl ether(MTBE) and 2,2,4-trimethylpentane, and methyl ethyl ketone (MEK) and 2,2,4-trimethylpentane, and the density of polar-polar liquid mixture of MTBE and MEK were measured by densitometer at 278.15 K, 288.15 K and 298.15 K, respectively. The excess molar volume of the binary systems calculated from the measured density was shown good agreement with the calculated one by the cubic Peng-Robinson- Stryjek-Vera (PRSV) equation of state together with Huron-Vidal mixing rule and it confirmed that the cubic PRSV equation of state could be used in the molar volume calculation of polar mixture.