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111.
Byung Joo Park Sung Woo Sohn Won Tae Kim Do Hyang Kim 《Journal of Alloys and Compounds》2009,483(1-2):260
Structural evolution during heat treatment of melt spun Ti36Y20Al24Co20 alloy was studied using differential scanning calorimetry, X-ray diffractometry and transmission electron microscopy. The as-melt spun Ti36Y20Al24Co20 specimen showed a hierarchical complex microstructure consisting of Ti-rich and Y-rich amorphous phases and crystallized with two-step process. Crystallization in the phase separated two phase mixture took place in a confined mode due to different thermal stability and complex microstructure, resulting in various nano-scaled microstructural formation ranging from fine distribution of crystalline particles in amorphous matrix to fine distribution of amorphous particles in crystalline matrix. 相似文献
112.
Insuk Sohn 《Computational statistics & data analysis》2008,52(8):4104-4115
There are many sources of systematic variations in cDNA microarray experiments which affect the measured gene expression levels. Print-tip lowess normalization is widely used in situations where dye biases can depend on spot overall intensity and/or spatial location within the array. However, print-tip lowess normalization performs poorly in situations where error variability for each gene is heterogeneous over intensity ranges. We first develop support vector machine quantile regression (SVMQR) by extending support vector machine regression (SVMR) for the estimation of linear and nonlinear quantile regressions, and then propose some new print-tip normalization methods based on SVMR and SVMQR. We apply our proposed normalization methods to previous cDNA microarray data of apolipoprotein AI-knockout (apoAI-KO) mice, diet-induced obese mice, and genistein-fed obese mice. From our comparative analyses, we find that our proposed methods perform better than the existing print-tip lowess normalization method. 相似文献
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Although many products are made through several tiers of supply chains, a systematic way of handling reliability issues in a various product planning stage has drawn attention, only recently, in the context of supply chain management (SCM). The main objective of this paper is to develop a fuzzy quality function deployment (QFD) model in order to convey fuzzy relationship between customers needs and design specification for reliability in the context of SCM. A fuzzy multi criteria decision-making procedure is proposed and is applied to find a set of optimal solution with respect to the performance of the reliability test needed in CRT design. It is expected that the proposed approach can make significant contributions on the following areas: effectively communicating with technical personnel and users; developing relatively error-free reliability review system; and creating consistent and complete documentation for design for reliability. 相似文献
115.
Kee-Sun- Sohn Yoon Young Choi Kyoung Hwa Kim Se Young Choi Hee Dong Park 《Journal of Materials Science: Materials in Electronics》2001,12(3):179-186
The photoluminescence of Terbium-activated yttrium aluminate with the general formula Y3-xTbXAl5O12was investigated as a function of Tb3+concentration. The main attention is focused on the 5D3/5D4fluorescence and its energy transfer behavior. The emission and excitation spectra were measured in terms of Tb3+concentration and analyzed in view of the application for plasma display panel (PDP). Also, the diffuse reflectance spectra were measured and analyzed in the range from VUV to UV. As a result, the yttrium aluminate was found to have a broad excitation band extending from VUV to UV range and to show the typical concentration quenching behaviors both for 5D3and 5D4fluorescence. The energy transfer was investigated by analyzing the decay curve of 5D3and 5D4emission based on the multipolar interaction or the exchange interaction. The decay curves of 5D3emission, for which well known cross relaxation has been accepted as a main factor, were analyzed by Inokuti and Hirayama's formula based on the direct quenching scheme. The decay curves of 5D4emission were analyzed by Yokota and Tanimoto's formula based on the diffusion limited quenching scheme. 相似文献
116.
Dinesh Kumar Misra Sung Woo Sohn Won Tae Kim Do Hyang Kim 《Science and Technology of Advanced Materials》2008,9(4)
The plastic deformation of Ti45Zr16Be20Cu10Ni9 bulk metallic glass has been investigated by nanoindentation performed with loads ranging from 10 to 200 mN in a wide range of loading rates. The plastic flow in the alloy exhibited conspicuous serrations at low loading rates. The serrations, however, became less prominent as the rate of indentation increased. Atomic force microscopy showed a significant pile-up of materials around the indents, indicating that a highly localized plastic deformation occurred under nanoindentation. The possible mechanism governing the plastic deformation in bulk metallic glass specimens is tentatively discussed in terms of strain-induced free volume. 相似文献
117.
Seong-Ho Choi Seungho Lee Sang-Jun Kim Sang-Ho Sohn Hee-Dong Kang Yu-Ping Zhang Kwang-Pill Lee Jong-Han Chun 《Catalysis Letters》2005,105(1-2):59-65
Polyvinypyrrolidone (PVP)-stabilized Pd-Ag bimetallic colloids were successfully prepared in an acetone:2-propanol solution
mixture of palladium acetate and silver perchlorate, and in an aqueous solution of palladium nitrate and silver nitrate by
γ-irradiation. The prepared PVP-stabilized bimetallic nanoparticles were characterized by UV, TEM, XRD, and XPS. In Pd–Ag
bimetallic nanoparticles, the XPS data indicated that the constituent elements were in the metallic state, and the palladium
atoms were concentrated on the surface of the alloy cluster. These PVP-stabilized bimetallic nanoparticles were used as catalysts
for hydrogenation of cis,cis-1,3-cyclooctadiene (COD). 相似文献
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120.
This paper presents a novel method for cost aggregation and occlusion handling for stereo matching. In order to estimate optimal cost, given a per-pixel difference image as observed data, we define an energy function and solve the minimization problem by solving the iterative equation with the numerical method. We improve performance and increase the convergence rate by using several acceleration techniques such as the Gauss-Seidel method, the multiscale approach, and adaptive interpolation. The proposed method is computationally efficient since it does not use color segmentation or any global optimization techniques. For occlusion handling, which has not been performed effectively by any conventional cost aggregation approaches, we combine the occlusion problem with the proposed minimization scheme. Asymmetric information is used so that few additional computational loads are necessary. Experimental results show that performance is comparable to that of many state-of-the-art methods. The proposed method is in fact the most successful among all cost aggregation methods based on standard stereo test beds. 相似文献