• 전기의세계
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• v.23 no.4
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• pp.46-52
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• 1974

Generally, it has been regarded that there are two kinds of the effect of the electrodes, especially of the cathode in the gas discharge, (a) the effect caused by the difference of the cathode meterial and (b) the effect by the change of the cathode surface state even in the same meterials. Thus the two effects must be investigated independently to study the roles of the cathode in gas discharges. This paper measured sparking voltage in Rare gas (Ar, He) for the change of sparking voltage in repeating sparks and for the effect of (a) and (b) mentioned above, under the condition that the desorption of impurities from the cathod can be nigligible, and it is obtained that the correlative relations of the work function, sparking voltage and secondary coefficient are comparatively simple. In addition, the interesting character of the minimum point of the paschen's curves is found. The results were as follows; 1) The value of (pd)min with minimum pint of sparking voltage, (Vs)min, is 0.7-0.9 Torr. cm in Argon, but is 5.6-7.1 Torr. cm in Helium, and Paschen's curve in Helium shows slow curve than in Argon. 2) The minimum point of the Paschen's curve is satisfied actually Townsend's self sustaining criterion in Argon, but non-satisfaction in Helium, and the Townsend's secondary coefficient .gamma. action have compound property (.gamma.$_{i}$, .gamma.$_{p}$, .gamma.$_{m}$) in Helium. 3) The dependenting character of work function in Helium is less than in Argon. 4) The minimum point of sparking voltage increase under oxidized electrode than clear electrode in Au and Ag, but minimum point decrease in Ni and Cu.

• Journal of KIISE:Computing Practices and Letters
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• v.12 no.5
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• pp.286-299
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• 2006

Due to the continuing technical progress in the capabilities of modeling, simulation, and sensor devices, huge volume data with very high resolution are common. In scientific visualization, various interactive real-time techniques on high performance parallel computers to effectively render such large scale volume data sets have been proposed. In this paper, we present a mobile volume visualization system that consists of mobile clients, gateways, and parallel rendering servers. The mobile clients allow to explore the regions of interests adaptively in higher resolution level as well as specify rendering / viewing parameters interactively which are sent to parallel rendering server. The gateways play a role in managing requests / responses between mobile clients and parallel rendering servers for stable services. The parallel rendering servers visualize the specified sub-volume with rendering contexts from clients and then transfer the high quality final images back. This proposed system lets multi-users with PDA simultaneously share commonly interesting parts of huge volume, rendering contexts, and final images through CSCW(Computer Supported Cooperative Work) mode.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.9
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• pp.67-75
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• 2006

A fully nonlinear model accounting for swirling effect has been applied in analyzing the dynamic response for a classical swirl injector. The current work applied highly accurate Boundary Element Methods (BEMs) in assessing its static and dynamic characteristics. On the basis of moving surface treatment method and surface instability study, which are obtained from the previous static characteristics analysis in pressure-swirl injectors, this work was expanded for analyzing the dynamics of a classical swirl injector. The dynamic response through injector components for disturbed inflow condition was investigated. The modified code was validated from comparison with the theoretical result for a typical swirl injector. Clearly the simulated result shows the interesting characteristics of swirl injectors to provide either amplification or damping of the input disturbance through each component. These results give promise in applying the current model to nonlinear dynamic characteristics of swirl injectors.

• Korean Journal of Social Welfare
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• v.63 no.3
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• pp.239-260
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• 2011

It is very interesting phenomenon that despite a broad consensus on the need for social worker to take cultural aspects into professional practice, thus to be a culturally competent, a number of materials criticising the concept of cultural competence have emerged in these days simultaneously. The main purpose of the study is to clarify such phenomenon, which means that this article is trying to analyze the contents of such critical discourse on cultural competence and the validity of those contents. The result of the study finds out that most of the arguments can be categorized into three aspects: epistemological, ethical, ontological, and that most of the main ideas of the critical discourses have been borrowed from a branch of critical social work theories, especially highly influenced from Foucault and Derrida. This article argues that critical discourses have some significant problems which make a conflict with traditional values and tenets in social work as a human service profession. First, epistemologically, the critical discourse fails to differentiate the matter of discovery from that of justification, which brings the cultural competence to the brink of agnosticism. Second, ethically, insisting that there should be no foundational criteria for cultural hierarchy in term of rightness or goodness, the critical discourses reveal their intrinsic limitations in solving ethical dilemmas and conflict in real world, which can be considered as a kind of evasion of responsibility in disguise of cultural relativism. Third, in practical vein, critical discourses are largely in effective in specifying the concrete model to realize their own ideas, and furthermore they unintentionally promote context-blind perspectives that eclipses the significance of structural and systematical impacts on the cultural identity.

• Journal of Korean Home Economics Education Association
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• v.9 no.2
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• pp.115-130
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• 1997

The purposes of this study are：(1) to analyze the learning content & subjects on the area of clothing and textiles in Home Economics for Young Men： A Teaching Guide, (2) to compare it with the learning content & subjects on the area of clothing and textiles in Home Economics teaching guides in the middle school in Korea, (3) to provide preliminary data for developing the learning content & learning method on clothing and textiles education for middle school students. To implement these proposals, Home Economics for young Men： A Teaching Guide in U.S.A and 6 Home Economics teaching guides for the middle school in Korea are reviewed and analyzed. The research findings were as follows： 1. Home Economics for Young Men is characterized as including： (1) interesting learning contents for girls and boys in the middle school, (2) learning contents for helping students to work on their own initiative (3) learning contents related to actual life, (4) practical consumer education content related to clothing and textiles area, (5) learning contents for developing originality, (6) learning contents related to vocational education. 2. The subjects in Home Economics for Young Men give careful considerations especially on how to learn. They are based on the idea that middle school students have to learn and to solve the subject by themselves. 3. Learning contents on Home Economics teaching guides for middle school in Korea are different from learning contents in Home Economics for Young Men in the subject & the form of description, the subject matter of practice in clothing area, the standpoint of description on clothing matters. The subjects in Home Economics teaching guides for middle school in Korea don’s give careful consideration on how to learn. There are little idea that middle school students have to learn and to solve the subject by themselves.

• Korea Journal of Hospital Management
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• v.6 no.2
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• pp.86-114
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• 2001

As the environment related to hospital operation has changed very competitively in recent years, a need to reform the hospital management is ever growing. For that reason, it has become more urgent and strategically important for us to diagnose the organizational culture of the hospitals and to make efforts to change them towards more performance- and customers-oriented one. So far, there have been many studies done on the hospital organizations. However, this research distinctively attempts to base itself on the competing values approach in studying the organizational culture and empirically examine how different profiles of the organizational culture may have an impact on the organizational performances in hospital organizations. The results of this study has showed several interesting findings and posed the discussions to be dealt with. First, most hospitals selected for this research are characterized by the inner-oriented culture with more focused on 'hierarchy' and 'relationship-oriented' culture rather than on 'reform' and 'work-oriented' one. And the strong 'hierarchy-oriented' culture is a very general phenomenon in the sample hospitals. From these findings, we can inference that despite the recent efforts of most Korean hospitals for organizational change and innovation they still have long distance way to go. In addition, another important implications of this research has come from the analysis of the relationships between the cultural profiles and organizational performances. For this purpose, this research has conducted a series of cluster analysis and identified four distinct cultural profiles from the sample organizations. Several major findings are as follows. First, with respect to the dependent variable of 'job satisfaction' perceived by the nurses working in the sample hospitals, we found that the balance of competing organizational values had more positive impact on the job satisfaction. This result confirms the hypothesis of competing values model on the organizational performances. However, such result was not replicated on the other dependent variable, 'patients' satisfaction'. The reasons for these results and other discussions including the limitations of this study are suggested.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.2
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• pp.38-45
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• 2003

This paper intends to analyze the movement characteristics of the suspended solid(SS) generated in a riprap work which is the most widespread process in harbor construction. The generation and movement behaviors of SS are investigated when 1) basic ripraps (0.001~0.03㎥) are cast for breakwater construction, 2) ripraps are loaded on carrier for riprap casting in the sea-wall construction of dredged material pocket, and 3) ripraps for inner filling are cast. The result of the present study shows that the SS generation is considerable when basic ripraps are cast for breakwater construction and the SS diffusion reaches up to 500m in high tide period. When ripraps are loaded on carrier, the SS is generated by the ripraps running down into sea from carrier, thereby showing a high concentration of SS in the vicinity of carrier. In the surface layer, SS distribution is confined in the vicinity of the carrier due to the prompt sinking of the SS. However the SS in the bottom layer is diffused approximately up to loom and then the SS concentration reaches to the background one. In the riprap (less than 0.03㎥) casting for inner filling using pork crane, SS is diffused approximately up to 300m in the surface layer and more than 300m in the bottom layer. It is quite interesting that the movement of the SS generated in harbor construction is mainly controlled by wind drift in the surface layer and tidal current in the bottom layer, and also the diffusion range of SS in the bottom layer is much larger than that in the surface layer.

• The Research Journal of the Costume Culture
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• v.15 no.2 s.67
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• pp.221-231
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• 2007

In the modern society of the 21st century where the visuality is emphasized, the illustration which expresses one symbol by embodying it is getting more spotlight than the use of character. Specifically, the fashion illustration serves the role of image promotion in other fields, for such as book, magazine, etc, as well as the fashion, and is taking root in daily lives. In response to that, this study researched on the fusion style fashion and the fashion illustration by using the violet color. The violet color which symbolizes the mysticism is being applied to society and culture in various forms, and has been considered as a precious color that represents god since ancient time, and still possesses its mysterious image even in the modern times. Moreover, as the appearance of fusion styled clothes which consolidates the latest trend image of the west and east is combined with the mysterious image of the purple to express new cultural image beyond highlighting specific image element of a country, the study on the fashion illustration based on the clothes based on the purple and fusion style would be very interesting. This study tried to produce the work that aims at the practical study based on the purple & fusion style and the theoretical consideration of fashion illustration through the analysis and investigative study of preceding studies. The findings from the study is like this: First, the violet the color, which represents the mysticism, can be confirmed to be an sophisticated, elegant and attractive image color that leads the modern fashion. Second, the fusion style which is coming into the spotlight recently can be found to have a great visual effect of consolidating the image of the west and east through the mixture with the purple color. Third, it was confirmed in our production of works that the fashion illustration was expressing a mysterious and new fusion style by blending appropriately with the purple color.

• Transactions on Electrical and Electronic Materials
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• v.18 no.1
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• pp.7-12
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• 2017

This work takes place in the context of the development of a transport phenomena simulation based on group III nitrides. Gallium and boron nitrides (GaN and BN) are both materials with interesting physical properties; they have a direct band gap and are relatively large compared to other semiconductors. The main objective of this paper is to study the effect of boron content on the electron transport of the ternary compound $B_xGa_{(1-x)}N$ and the effect of the temperature of this alloy at x=50% boron percentage, specifically the piezoelectric, acoustic, and polar optical scatterings as a function of the energy, and the electron energy and drift velocity versus the applied electric field for different boron compositions ($B_xGa_{(1-x)}N$), at various temperatures for $B_{0.5}Ga_{0.5}N$. Monte carlo simulation, was employed and the three valleys of the conduction band (${\Gamma}$, L, X) were considered to be non-parabolic. We focus on the interactions that do not significantly affect the behavior of the electron. Nevertheless, they are introduced to obtain a quantitative description of the electronic dynamics. We find that the form of the velocity-field characteristic changes substantially when the temperature is increased, and a remarkable effect is observed from the boron content in $B_xGa_{(1-x)}N$ alloy and the applied field on the dynamics of holders within the lattice as a result of interaction mechanisms.

• Advances in nano research
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• v.10 no.5
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• pp.449-460
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• 2021

Flexoelectricity is an interesting materials' property that is more touchable in small scales. This property beside the sandwich structures placed in the center of scientists' attention due to their extraordinary effects on the mechanical properties. Furthermore, in the passage of decades, more elaborated sandwich structures took into consideration results from using honeycomb core. This kind of structure, inspiring from honeycomb core, provides more stiffness to weight ratio, which plays a crucial role in different industries. In this paper, based on the Love-Kirchhoff's hypothesis, Hamilton's principle, modified couple stress theory and Fourier series analytical method, equations of motion for a sandwich plate containing a honeycomb core integrated by two face-sheets have derived and solved analytically. The equations of both face sheets have derived by flexoelectricity consideration. Moreover, it should be noticed that the whole structure rests on the visco-Pasternak foundation. Conducting current research provided an acceptable and throughout study based on flexoelectricity to address the effect of materials' characteristics, length-scale parameter, aspect, and thickness ratios and boundary conditions on the natural frequency of honeycomb sandwich plates. Also, based on the presented figures and tables, there is a close agreement between previous studies and recent work. Due to the high ratio of strength to weight, current model analyzing is capable of taking into account for different vehicles' manufacturing in a high range of industries.