• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.1
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• pp.1-8
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• 1990

In this paper, the transient electromagneti wave scattering at dielectric cylinder is studied by new numerical analysis method. Basic formulation of boundary integral equation (BIE) for numerical method is started weighted residual technique. BIE is made to two simultaneous equation at surface inner and outside point of dielectric cylinder in extended boundary condition (EBC) and surface boundary condition (SBC). Numerical method is used Boundary element method (BEM) that is two form, one is direct method and the other is indirect method, so that this method that transformes operator inversion martics is used numerical analysis. A good agreement of this numerical solution and the other results is obtained.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.293-301
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• 2013

The purpose of this study was to find the space perception by the scene and to analyze the characteristics in the exhibition space. The data for the analysis was collected through a questionnaire survey method. The questionnaire is composed of a scene selection on the panoramic photographs of the exhibition space. 'The 4 Rivers Cultural Center - The ARK' was selected as the subject of this survey. The results of the study are presented as follows : First, the space perception perceived imaged scenes rather than the specific elements of space. Second, the space perception was revealed through the 'Form', 'Materials', 'Light', 'Lighting', 'Furniture' and 'Media' of notable elements. Also that was perceived by forming 'Line', 'Surface' and 'Volume'. Particularly, the perception of 'Surface' was higher than 'Line' and 'Volume'. 'Surface' was perceived mostly through the 'Color'. The perception of 'Line' was positive to 'Boundary' or 'Continuous placement of the light'. In addition, the perception of 'Volume' was positive to 'The curve of the form', 'Transparent material', 'Three-dimensional elements'. Finally, The type of space perception was chosen as 'Extension', 'Center', 'Deep', 'Boundary' and 'Formative'. In this way, the results of this study will set a foundation for developing design methods to induce the space perception by the scene in the exhibition space.

• Journal of the Korean Society of Costume
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• v.61 no.7
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• pp.80-100
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• 2011

The purpose of this research is to classify that fashion and art in the twentieth century broadened the creative field by individually applying each other's ideas or through collaboration. This paper analyses the work of individual artists and fashion designers who created work on the boundaries of fashion and art. These samples are selected to extract features related to specific periods as it is proposed that contemporary creation has been developed from a combination of fashion and art, sharing their distinct concerns. Accordingly, this research will focus on the collaboration between fashion and art in the twentieth century from the aspect of 'fashion into art'/'art into fashion' in order to analyse the historical flow, and thereby examine the relationship between fashion and art. The cross-fertilization between fashion and art was initiated as an imitation of form in the early twentieth century, and led to a 'new cross-disciplinary form' which exists on the boundary of fashion and art. This paper considers the relationship between fashion and art from the perspective of sharing intrinsic concepts and the creation of a new creative sphere. It analyses the characteristics of the works of fashion designers and artists whose works lie on the boundary between fashion and art.

• Advances in nano research
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• v.14 no.1
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• pp.45-65
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• 2023

This paper aimed to investigate the nonclassical size dependent free vibration behavior of regularly squared cutout viscoelastic nanobeams. The nonlocal strain gradient elasticity theory is modified and adopted to incorporate the viscoelasticity effect. The Kelvin Voigt viscoelastic model is adopted to model the linear viscoelastic constitutive response. To explore the influence of shear deformation effect due to cutout, both Euler Bernoulli and Timoshenko beams theories are considered. The Hamilton principle is utilized to derive the dynamic equations of motion incorporating viscoelasticity and size dependent effects. Closed form solutions for the resonant frequencies for both perforated Euler Bernoulli nanobeams (PEBNB) and perforated Timoshenko nanobeams (PTNB) are derived considering different boundary conditions. The developed procedure is verified by comparing the obtained results with the available results in the literature. Parametric studies are conducted to show the influence of the material damping, the perforation, the material and the geometrical parameters as well as the boundary and loading conditions on the dynamic behavior of viscoelastic perforated nanobeams. The proposed procedure and the obtained results are supportive in the analysis and design of perforated viscoelastic NEMS structures.

• Tunnel and Underground Space
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• v.1 no.2
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• pp.181-203
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• 1991

The effects of geologic structures such as rock joins and bedding planes on the thermal conductivity of a discontinuous rock mass are studied. The expressions for the equivalent thermal conductivities of jointed rock masses are derived and found to be anisotropic. The degree of anisotropy depends primarily on the thermal properties contrast between the joint phase and surrounding intact rock, the joint density expressed as volume fraction and the inclination angle of the joint. Within the context of 2-dimensional finite element heat transfer scheme, the isotherms around a circular hole are analyzed for both the isotropic and anisotropic rock masses in 3 different thermal boundary conditions. i.e. temperature, heat flux and convection boundary conditions. The temperature in the stratified anisotripic rock mass is greatly influenced by the thermal properties of the rock formation in contact with the heat source. Using the excavation-temperature coupled elastic plastic finite element method, analyzed is the thermo-mechanical stability of a circular opening subjected to 10$0^{\circ}C$ at a depth of 527m. It is found that the thermal stress concentration was enough to deteriorate the stability and form a plastic yield zone around the opening, in contrast to the safety factor greater than 2 resulted form the excavation-only analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1057-1060
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• 2001

By comparison of the experimental results in two systems of ZnO varistors, its appear that Sb$_2$O$_3$is the indispensable element for twinning in ZnO varistors, and the Zn$_{7}$Sb$_2$O$_{12}$ spinel acts as the nucleus to form twins. A1$_2$O$_3$is not the origin of twinning in ZnO varistor, but it was found that A1$_2$O$_3$could strengthen the twinning and form a deformation twinning by ZnA$_{12}$O$_4$-dragging and pinning effect. The inhibition ratios of grain growth and nonuniformity of two systems ZnO varistors increase with the increase of A1$_2$O$_3$content. The twins affect the inhibition of grain growth, the mechanism could be explained follow as : twins increase the mobility viscosity of ZnO grain and grain boundary, and drag ZnO grain and liquid grain boundary during the sintering, then the grain growth is inhibited, and the microstructure becomes more uniform.orm.m.

• Phonetics and Speech Sciences
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• v.9 no.4
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• pp.9-17
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• 2017

The aim of this study is to examine whether Chinese Korean learners (CKL) can correctly produce the aspiration in 'a lenis obstruents /k/, /t/, /p/, /ʧ/+/h/ sound' sequence at the lexical and post-lexical level. For this purpose 4 Korean native speakers (KNS), 10 advanced and 10 intermediate CKL participated in a production test. The material analyzed consisted of 10 Korean sentences in which aspiration can be applied at different prosodic boundaries (syllable, word, accentual phrase). The results showed that for KNS and CKL, the rate of application of aspiration was different according to prosodic boundaries. Aspiration was more frequently applied at the lexical level than at the post-lexical level and it was more frequent at the word boundary than at the accentual phrase boundary. For CKL, pronunciation errors were either non-application of aspiration or coda obstruent omission. In the case of non-application of aspiration, CKL produced the target syllable as an underling form and they did not transform it as a surface form. In the case of coda obstruent ommision, most of the errors were caused by the inherent complexity of phonological process.

• Advances in nano research
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• v.14 no.4
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• pp.303-312
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• 2023

In this study, the bifurcation analysis of functionally graded material is done using exponential volume fraction law. Shell theory of Love is used for vibration of shell. The Galerkin's method is applied for the formation of three equations in eigen value form. This eigen form gives the frequencies using the computer software MATLAB. The variations of natural frequencies (Hz) for Type-I and Type-II functionally graded cylindrical shells are plotted for exponential volume fraction law. The behavior of exponent of volume fraction law is seen for three different values. Moreover, the frequency variations of Type-I and -II clamped simply supported FG cylindrical shell with different positions of ring supports against the circumferential wave number are investigated. The procedure adopted here enables to study vibration for any boundary condition but for brevity, numerical results for a cylindrical shell with clamped simply supported edge condition are obtained and their analysis with regard various physical parameters is done.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.535-546
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• 2019

The paper presents a closed-form analytical solution for the ultimate strength of sandwich panels with metal faces and an elastic isotropic core during combined in-plane compression and lateral pressure under clamped boundary condition. By using the principle of minimum potential energy, the stress distribution in the faces during uni-axial edge compression and constant lateral pressure was obtained. Then, the ultimate edge compression was derived on the basis that collapse occurs when yield has spread from the mid-length of the sides of the face plates to the center of the convex face plates. The results were validated by nonlinear finite element analysis. Because the solution is analytical and closed-form, it is rapid and efficient and is well-suited for use in practical structural design methods, including repetitive use in structural optimization. The solution applies for any elastic isotropic core material, but the application that stimulated this study was an elastomer-cored steel sandwich panel that had excellent energy absorbing and protective properties against fire, collisions, ballistic projectiles, and explosions.

• KCI Concrete Journal
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• v.12 no.2
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• pp.73-84
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• 2000

A new form of construction utilizing structural steel as the boundary elements in ductile flexural concrete walls is proposed to solve the bar congestion problems in such a heavily reinforced region, while maintaining the ductility and energy absorption capacity comparable to their traditional form. Two wall specimens containing rectangular hollow structural sections (HSS) and channels at their ends respectively, and one companion standard reinforced concrete wall specimen with concentrated end reinforcement were constructed and tested under reversed cyclic loading to evaluate the construction process as well as the structural performance. Initially, all three specimens were chosen and detailed with some caution to have approximately the same flexural capacity without change of the original shape and dimension of a rectangular cross section correction. Analysis and comparison of test results indicated that the reversed cyclic responses of three walls showed similar hysteretic properties, but in those with steel boundaries, local buckling of the corresponding steel webs and flanges following significant yielding was a dominant factor to determine the hysteretic response. The monotonic and cyclic responses predicted based on a sectional approach was also presented and found to be in good agreement with measured results. Design recommendations considering local instability of the structural steel elements and the interaction between steel chords and a concrete web member in such a composite wall are presented.