• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.5 s.176
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• pp.1352-1361
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• 2000

We obtain a micromechanics-based Helmholtz free energy and then in the framework of irreversible thermodynamics, a kinetic relation, a martensitic nucleation criterion and the reorientation criterion of martensitic variants are obtained. These relations are valid for a three-dimensional proportional and non-proportional loadings and for a combination of mechanical and thermal loading. From the simulated pseudoelastic stress-strain relation of a single crystal with loading rate effect, polycrystalline behavior in case of proportional and non-proportional loading is predicted by a homogenization method. The obtained results are compared quantitatively with experimental results.

• Journal of the military operations research society of Korea
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• v.35 no.3
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• pp.101-117
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• 2009

The objective of this study is to find relations between success factors of project management and user satisfaction and usage for analysis report. According to emprical study, the main factors that affect user satisfaction are requirement and proper planning. And the main factors that affect usage are expert of analysis, proper planning and user satisfaction.

• Macromolecular Research
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• v.11 no.4
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• pp.224-230
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• 2003

The blends of polypropylene (PP) with glass filled thermotropic liquid crystalline polymer (LCP-g) have been prepared by melt mixing techniques at different blend ratios. The thermal, dynamic mechanical, crystalline and morphological characteristics of these blends were investigated. Higher percent crystallinity was observed for 10% level of LCP-g in the blend in comparison to that of other blend ratios. The thermal stability increased with LCP-g concentration in the blend with PP. The variation of storage modulus, stiffness and loss modulus as a function of blend ratios suggested the phase inversion at the 50% level of LCP-g in the blend. The scanning electron microscopy (SEM) photographs showed the creation of voids and destruction of the fiber structures during the dynamic mechanical measurements. Processing behavior of the blends depended on the fiber forming characteristics of LCP-g, which again varied with the molding temperatures.

• Bulletin of the Society of Naval Architects of Korea
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• v.24 no.1
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• pp.9-16
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• 1987

The second-order steady horizontal force and vertical moment are derived for a freely-floating body in water of finite depth. Momentum relations are used in terms of the Kochin function in the fluid region far from the body. The general results look very similar to those for deep water. The water depth is formally reflected in terms of the ratio between the phase and group velocities of incident waves. Computations are made for a Series 60 hull($C_B=0.6$) and are compared with the corresponding results of deep water. It is shown that the vertical drift moment for slender ships becomes completely free from water depth when the wave-ship length ratio is taken as parameter.

• Journal of Plant Biology
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• v.7 no.4
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• pp.9-14
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• 1964

According to the results measured the respiratory quotient of Saccharomyces cerevisiae with neutron radiation by manometric direct method, the respiratory quotient of them was stimulated at the dose(7$\times$106N/$\textrm{cm}^2$/sec) of neutron radiation for 60 seconds, and was inhibited in each group irradiated at the high dose (7$\times$108N/$\textrm{cm}^2$/sec) of neutron. Its physiological effects influenced on neutron had relations with respiratory quotient, reproductive rate and fermentation in the curve of normal logarithmic phase. The multiple reactions which appeared in yeast, indicated that a great deal of physiological function were closely correlated with the irradiated dosage of neutron. The kinds of free amino acid in yeast irradiated with neutron were different from those of unirradiated yeast. The activityof dehydrogenase system accelerated the metabolic function of yeast irradiated at some low dose of neutron. By this results, it may demonstrate that the fact which the phenomena obtained in the stimulation of neutron possess its character for several generation, is dependent on the theory of mutation. Subsequently, it seemed reasonable certain dominant type of microorganisms.

• Korean Journal of Materials Research
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• v.17 no.9
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• pp.500-506
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• 2007

The effects of anisotropic surface energy on the microstructure development of porous materials have been studied through Monte Carlo simulation using a three dimensional lattice. The changes in porosity ($f_v$), mean grain diameter ($D_s$), fraction of connected pores ($f_{v,c}$) and contiguity of the solid phase (C) were examined in cases with three different ${\gamma}_{SV}$ relations and initial grain diameters ($D_{s,o}$). It has been found that larger ${\gamma}_{SV}$ enhances sintering of particles and increases C and does not change $D_s$. And Introducing anisotropic ${\gamma}_{SV}$ brought an increase in $f_v$ and $f_{v,c}$ and an decrease in $D_s$ and C, and this tendency become more marked for fine $D_{s,o}$.

• Korean Journal of Computational Design and Engineering
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• v.6 no.4
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• pp.254-262
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• 2001

It is not possible to exchange parametric information of CAD (Computer Aided Design) models based on the current version of STEP (Standard leer the Exchange of Product model data). The design intent can be lost during the STEP transfer of CAD models. The ISO Parametrics Group has proposed the SMCH (Solid Model Construction History) schema in June 2000 that includes structures fur exchange of parametric information. This paper proposes the macro parametric approach that is intended to provide capabilities to transfer parametric information. In this approach, CAD models are exchanged in the form of macro files. The macro file contains user commands which are used in the modeling phase. To exchange CAD models using the macro parametric approach, modeling commands of commercial CAD systems are analyzed. Those commands are classified by the grouping method suggested by Bill Anderson. As a neutral file format, a standard modeling commands set has been defined. Mapping relations between the standard modeling commands set and the native modeling commands set of commercial CAD systems are defined.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.1
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• pp.60-69
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• 2009

Recently, request far application of advanced commercial technology to the defense acquisition process, to reduce the budget and shorten development time, has been increased. To accomplish these goals, the Advanced Concept Technology Demonstration(ACTD) is used for the defense acquisition process in Korea. And User Utility Assessment is tested to make a decision for transition to acquisition process. But this process does not include measurement of technology maturity and impacts of interface and interaction among the technologies. In this research, we propose the needs of measurement of TRL and IRL and application of SRL to reduce the risk during development phase, to understand the relations of technologies, and to fulfill the requirement far transition of the ACTD project to system development and demonstration process.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.28-35
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• 1998

The seismic overstrength factor $\Omega$ is evaluated for 4-story reinforced concrete buildings in Korea(of which seismic intensity is low). The study model is designed according to aseismic guideline research - phase II in Korea. The effect of variation of span length and bay number, dead load is considered, especially including the variation of hardening ration after yielding. And push-over analysis is performed, in which the external and internal frame is connected by rigid-link and the $\Omega$ is calculated using the roof drift ratio at 2%. For Zone I, the mean value of $\Omega$ is ranged form 2.3 to 2.5, For Zone II, from 3.1 to 3.4. For low hardening ratio(3%) after yielding, $\Omega$ has little relations with the number of bay, like as the results of other research. But for 5% hardening ratio, $\Omega$ is increased as the number of bay is increased. Within general gravity-load bound, the variation of D.L. has variation of D. L. has no effect on $\Omega$. And, $\Omega$ is increased as the span length is increased.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.3
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• pp.330-335
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• 2013

This paper performs two kinds of Field-Oriented Control (FOC) for dual three phase permanent magnet synchronous motor (DTP-PMSM).The first is based on vector space decomposition to study the effect of current harmonics on electromechanical energy conversion. And the second presents the coupling relations between two sets of windings using two d-q transformation. And then this paper has deeply studied the differences between these two strategies, the different effect on the control of harmonic current and the reason for these differences. MATLAB-based Simulation studies of a 3KW DTP-PMSM are carried out to verify the analysis of differences between the two FOC strategies.