• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.226-231
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• 2003

The viscous interaction of stern wave is studied by simulating the free-surface flows, including sub-breaking phenomena around a high speed catamaran hull advancing on calm water. The Navier-Stokes equation is solved by a finite difference method where the body-fitted coordinate system, the wall function and the triple-grid system are invoked. The numerical appearance of the sub-breaking waves is qualitatively supported by the experimental observation They are also applied to study precisely on the stern flow of S-103 as to which extensive experimental data are available. For the catamaran, computations are carried out for the mono ana twin hulls.

• 대한가정학회지
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• 제41권5호
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• pp.41-58
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• 2003

The purpose of this study is to develop and evaluate a social competence enrichment program for institutionalized children in early childhood. The program was developed to enhance institutionalized children's social competence. The program consists of sixteen 30-minute sessions. 19 institutionalized children (11 boys and 8 girls) participated in this program. The effect of this program was evaluated by institutionalized preschool children's emotional knowledge and interpersonal problem solving strategy. Assessment of emotional knowledge consists of identification and situation task. Interpersonal problem solving strategy includes forceful, prosocial, and manipulative strategy. Results showed that there was a significant experimental effect for emotional knowledge. Experimental children showed higher scores of emotional knowledge than control children. Also, there was a significant experimental effect for prosocial and forceful strategy. Experimental children showed higher ratio of prosocial strategy and lower ratio of forceful strategy than control children. The results of program evaluation revealed that this program was helpful for promoting institutionalized children's social competence.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.437-442
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• 2005

This paper deals with the measurement and analysis of radio characteristic of 424 MHz for using the automation of transmission and supply of electric power, ana automatic meter reading(AMR). Normally radio propagation characteristic is the base of system design, performance evaluation and choice of position of the base station in wireless communication. It is the most accurate way to design a base station through practical measurements, but it costs much time, money and engineers. So, we developed 424 MHz short range wave propagation model for AMR service.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1582-1589
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• 2004

The dynamic response of an eccentric Griffith crack in functionally graded piezoelectric ceramic strip under anti-plane shear impact loading is ana lysed using integral transform method. Laplace transform and Fourier transform are used to reduce the problem to two pairs of dual integral equations, which are then expressed to Fredholm integral equations of the second kind. We assume that the properties of the functionally graded piezoelectric material vary continuously along the thickness. The impermeable crack boundary condition is adopted. Numerical values on the dynamic stress intensity factors are presented for the functionally graded piezoelectric material to show the dependence of the gradient of material properties and electric loadings.

• Asia pacific journal of information systems
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• 제7권1호
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• pp.7-24
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• 1997

Executive information system (EIS) is a computer-based information system that supports decision makings ana management activities for senior executives. Data warehouse is a database that receives data copies from legacy systems and external data sources. Data warehouse is typically optimized for decision supports and can be an attractive solution for EIS implementation. This paper proposes an architecture for implementing EIS by the use of data warehouse. The architecture consists of ten implementation layers. Interrelationships among these layers are investigated for an effective EIS implementation. An EIS prototype for a real-fife enterprise is implemented to demonstrate the usefulness of the proposed architecture.

• 한국의류학회지
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• 제8권2호
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• pp.1-9
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• 1984

The purpose of this study was to investigate the relationship between personality traits ana clothing interest in girls' high school students The results were as follows : 1. In the personality traits of higher groups, the subjects scored highest in Sociability followed by Ascendancy and Self-Confidence in a descending order. In the clothing interest, the subjects scored highest in clothing interest of shopping followed by clothing interest of design & fashion, clothing interest of construction, clothing interest of management and clothing interest of psychological aspect in a descending order. 2. There was partially significant relationship between personality traits and clothing into rest. 3. There were highly significant relationships among clothing interest subscales. Specially, there was the highest significant relationship between clothing interest of design & fashion and clothing interest of shopping. 4. There was partially significant relationship between clothing interest and background of home.

• 한국재료학회지
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• 제15권5호
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• pp.340-347
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• 2005

Silver nanoparticles were synthesized by chemical reduction method from aqueous silver nitrate solution ana hydrazine as a reduction agent. The morphology, particle size and shape were dependent on the mixing method, reaction temperature and time, molar ratio of hydrazine and silver nitrate, the kind of surfactant, and the addition of surfactant. The stability of the colloidal silver was achieved by the adsorption of surfactant molecules onto the particle. Silver nanoparticles have a characteristic absorption maximum at 430 nm under UV irradiation. It was found that the colloid was nanometer m size and formed very stable dispersion of silver. The Ag nanoparticles obtained showed the spherical shape with the size range of 10-30 nm.

• 한국재료학회지
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• 제17권1호
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• pp.37-42
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• 2007

The effects of immersion time in the liquid nitrogen and deformation-induced martensitic transformation on the behavior of austenite stainless steels used for the hydrogen storage tank of auto-mobile at cryogenic temperature were investigated. With increasing of immersion time in the liquid nitrogen, the tensile strength of all austenite stainless steels at cryogenic temperature was increased because the martensite transformation of unstable austenite. The restraint of crack generation ana transmission also increased the tensile strength by the active ${\alpha}'$ transformation. The elongation decreasing of 321 steel is not the mechanical deformation of austenite phase but the stress induced martensite phase during the tensile test.

• 한국재료학회지
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• 제17권1호
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• pp.56-59
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• 2007

Recently, requirement for the ultra thin copper foil increases with smaller and miniaturized electronic components. In this study, we evaluated the surface morphology, crystal phase ana surface roughness of the copper film electrodeposited by pulse method without using additives. Homogeneous and dense copper crystals were formed on the titanium substrate, and the optimum condition was 25% duty cycle. Moreover, the surface roughness(Ra), $0.295{\mu}m$, is the smallest value in this condition. It is thought that this copper foil is good for electromigration inhibition due to the preferential crystal growth of Cu (111)

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.193-196
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• 2005

As global warming proceeds, South Eastern Asia is undergoing drought, and the harshness of drought in the middle area of Korea is increasing. Especially, there has been the worst spring drought in 2001 since the first meteorological observation, and the damages caused by that drought are being ana lysed in various ways. In this study, spectral indices derived from satellites are used to examine 2001 spring drought, and the application of MODIS Data products as the quantitative tool to analyse drought in the future is examined.