• Journal of the Korean Magnetics Society
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• v.10 no.1
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• pp.42-47
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• 2000

In the present work, we analyze theoretically the flow of magnetic fluids in a circular pipe with longitudinal magnetic field. We used governing equations induced Shliomis and Polar theory of Eringen. Using theoretical equations and distributions for the velocity, vorticity and angular velocity as the magnetic response, it is shown that magnetic fluid flow is non-Newtonian fluid. We investigate dynamic characteristic of magnetic fluid by comparing longitudinal magnetic field with transverse magnetic field. And, the limits, influence magnetic fluid, of the intensity of the magnetic field with polar, size and magnetic effect parameters are shown.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.3
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• pp.1-10
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• 2000

In order to predict the performance of subsonic/sonic ejector system and to provide fundamental data for a cost effective design, one dimensional gas dynamics theory was applied to the subsonic and sonic ejector systems with the second throat. In the current theoretical analyses, ejector throat area ratio, mass flow ratio and secondary stagnation pressure were derived as a function of the operating pressure ratio of the ejector, and the discharge coefficient of the primary nozzle and the loss coefficient of the diffuser were incorporated into the whole performance of the ejector system. The results of theoretical analysis can be applied to practical industrial use of subsonic and sonic gas ejector systems.

• Korean journal of communication and information
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• v.19
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• pp.185-211
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• 2002

Media convergence is prevalent all over the world, and is expected to change our lives dramatically in near future. Chaos theory is a new emerging theoretical approach to various social phenomena including organization management, economic system, stock market fluctuation, and so on. This thesis is intended to explain media convergence phenomena centered on internet media using basic concepts of chaos theory such as self-organization, co-evolution, and feedback loop. The implications of this tentative study are that we can apply chaos theory to media convergence as other social or natural phenomena, and that maintaining chaos state of media system is useful for accelerating creativities, and that developing media system as an organic system to cooperate with other relevant systems is helpful for promoting life qualities, and that establishing moral order or root value is desirable for implementing communicatopia.

• The Journal of the Acoustical Society of Korea
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• v.15 no.5
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• pp.65-72
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• 1996

A dynamic self-consistent method previously proposed and validated for the composites containing spherical inclusions is applied to the simplest two dimensional problems : SH wave propagation in unidirectional fiber reinforced composites. The self-consistent conditions for SH wave are derived without limitation on frequency and the wave speed and coherent attenuation are calculated for two composites. THe results of the present theory are compared with those of the multiple scattering theories and another self-consistent theory. At low volume fractions, the present theoretical results coincide with those of the multiple scattering theory using exact pair-correlation function, whereas the results based on another self-consistent theory deviate markedly from the others. As the volume fraction increases, the three theories give different results although they have qualitatively similar trends. The present theoretical results for composites considered in this paper exhibit less dispersion and physically realizable attenuation. An important observation is that the multiple scattering theory predicts vanishingly small attenuation at low frequency with volume fraction is high.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.7
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• pp.1463-1469
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• 2012

This paper has presented the influence of scaling theory on short channel effects of double gate(DG) MOSFET in subthreshold region. In the case of conventional MOSFET, to preserve constantly output characteristics,current and switching frequency have been analyzed based on scaling theory. To analyze the results of application of scaling theory for short channel effects of DGMOSFET, the changes of threshold voltage, drain induced barrier height and subthreshold swing have been observed according to scaling factor. The analytical potential distribution of Poisson equation already verified has been used. As a result, it has been observed that threshold voltage among short channel effects is grealty changed according to scaling factor. The best scaling theory for DGMOSFET has been explained as using modified scaling theory, applying weighting factor reflected the influence of two gates when scaling theory has been applied for channel length.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.275-285
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• 2010

This research examines the relation of dissatisfaction about own real conditions, deviant labeling, self-esteem, abuse from parent, victimization and juvenile delinquency(smoking, drinking, run-away, assault, taking away stuffs or money, larceny). The evidence of a strong relation of these factors and girls' delinquency is well known through empirical researches by feminist criminologists. Feminist criminology had attention to the gender-specific factors that could explain girls' delinquency. Most of conventional delinquency theories, such as social bond theory, differential association theory, focused on bad boys' deviant behaviors. These theories has not been designed to apply to girls' troubles. According to the conclusion of the research, there seems to support researches of feministic perspectives.

• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.5-15
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• 2004

It is worthwhile to verify the vertical stress distribution in soil mass for rigorous design of foundation. A series of laboratory model tests were performed to investigate the Boussinesq's theory on vertical stress increment in sandy soil mass caused by surface loading. The test results were also compared with Boussinesq's theoretical values. The Boussinesq's theoretical values were always smaller than test results under the footing regardless of depth. Outside of the footing the values were larger than the measured stress at the depth of just footing width. The theory and the test showed similar results when the depth reached two and three times the footing width. The vertical stress decreased as the applied load increased. These trends were confirmed to be valid for the considered range of the relative density of sand and/or the width of footing. More accurate values can be acquired by correcting the theoretical values using these results when Boussinesq's theory is used.

• Korean Journal of Social Welfare
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• v.58 no.3
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• pp.269-294
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• 2006

This paper aimed to analyze articles published in 9 Korean social work journals from 1979 to 2005 regarding the conceptualization of disability and the orientation of disability theories. Trends of disability theories have shifted from the division of the individual model and the social model to four models including individual materialist, individual idealist, social creationist, and social constructionist. As a result of categorizing the articles, it was revealed that the individual idealist position is the most popular and the social creationist position is increasingly popular. To understand disability holistically, the complexity of disability has to be addressed rather than focusing on one model.

• Korean Journal of Logic
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• v.19 no.2
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• pp.145-184
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• 2016

Williamson(1994) proved incompatibility of Gab Theory and Tarski T-schema. But this does not means that Gab Theory could not involve intuition on truth that is expressed by T-schema. I will show that Gab Theory and mutual entailment of 'p' and 'it is true that p'(p⊨T

and T

⊨p) are compatible. It will draw that Gab Theory can involve minimal intuition on truth. After all what I want to reveal is logical space for Gab Theory through the compatibility of the mutual entailment and negation of the Principle of Bivalence. To prove the compatibility, I will present a consequent relation which should be accepted whenever we accept Gab Theory and demonstrate Gab Theory and the mutual entailment imply following two thesis; 1) not-T

and T are not equivalent. 2) p entails T

but not-T

does not entails not-p.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.982-988
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• 2012

This paper has presented the relation of scaling theory and threshold voltage of double gate(DG) MOSFET. In the case of conventional MOSFET, current and switching frequency have been analyzed based on scaling theory. To observe the possibility of application of scaling theory for threshold voltage of DGMOSFET, the change of threshold voltage has been observed and analyzed according to scaling theory. The analytical potential distribution of Poisson equation has been used, and this model has been already verified. To solve Poisson equation, charge distribution such as Gaussian function has been used. As a result, it has been observed that threshold voltage is grealty changed according to scaling factor and change rate of threshold voltages is traced for scaling of doping concentration in channel. This paper has explained for the best modified scaling theory reflected the influence of two gates as using weighting factor when scaling theory has been applied for channel length and channel thickness.