• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.474-482
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• 2016

A Kelvin foam plate - widely used in the energy and transport industries as a lightweight structural material - was examined to estimate its Young's modulus using ultrasound. An isotropic tetrakaidecahedron foam structure was designed in SolidWorks and printed using 3D printer with an ABS plastic material. The 3D printed foam structure was used to build a foam plate with a 14 mm thickness ($50mm{\times}100mm$ in size) for the ultrasonic test. The Kelvin foam plate, a significantly porous medium, was completely filled with paraffin wax to enable the ultrasound to penetrate through the porous medium. The acoustic wave velocity of the wax-filled Kelvin foam was measured using the time of flight (TOF) method. Furthermore, the elastic modulus of the Kelvin foam was estimated based on an elastic structural model developed in this study. The Young's modulus of the produced Kelvin foam was observed to be approximately 3.4% of the bulk value of the constituent material (ABS plastic). This finding is consistent with experimental and theoretical results reported by previous studies.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.181-189
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• 1996

We investigated the relationship between the attitudes and brand preference on the expression techniques of advertisement of underwears and actual buying. A total of 233 females living in Seoul and Taejon were surveyed to compare these points of five major underwear brands (Vivien, Ravora, Wacoal, Calvin Klein, Let'xes).The survey showed that the responders reacted more positively to the revolutionary advertising techniques of the Calvin Klein, and Let'xes than to the more conservative techniques of the Vivien, Ravora, and Wocoal.The most positive response was obtained from the Calvin klein's revolutionary techniques while the most negative response from the Ravora. The most preferred brand was the vivien, followed by the Calvin Klein, Wacoal, Ravora, and Let'xes. The degree of preference varied according to the demographic variables like age, schooling, income, occupation, and residential area. As for the motive of preference, the Calvin Klein ranked best in respect to shape, quality, advertisement, and comfortability. The price factor was best for the Ravora. The Let'xes ranked worst in all aspects. However, there was discrepancy between the attitudes on advertisement and the actual buying, this implying that the attitudes on advertisement did not seem to directly affect actual purchasing behavior.

• 중국학논총
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• no.63
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• pp.91-120
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• 2019

《官話類編》是一部美國傳教士Calvin Wilson Mateer1892編寫的漢語教科書. 他1864年來華之後為了有效的传道编写語言學, 数学, 科学等方面的教科书并设立了山东养学堂和登州学会馆, 中国教育史上出了不少贡献. 《官話類編》是花25年的时间, 进行对北京, 南京, 九江, 潍县方言的方言调查后编写的, 内容簡單而且日常会话为主, 收到当时来华传教士的欢迎. 当时北京官话被认为是最时髦, 最流行的方言, 成为官方的公式语言. 虽然南方官话不是主流, 但还是在中国的更大地区里接受的官话方言. 《官話類編》里的北京官话有疑母消失, 见, 精组合流, 保存iai韵母, 梗曾摄, 宕江摄, 通摄存在文白异读等特征, 他记录的南京官话有见精组对立, 疑母消失, 保存入声和iai韵母, n, l和n, ŋ想混的特征, 为了解当时语言使用的情况以及音韵特征提供很有价值的信息.

• Journal of the Korean Chemical Society
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• v.16 no.6
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• pp.341-348
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• 1972

The significance of the curvature dependency correction of surface tension is studied in calculating the pore volume distribution of porous adsorbent from nitrogen adsorption isotherm. That is, Kelvin radii are calculated with curvature dependent surface tension values calculated by Chang et al, and then with these Kelvin radii, pore volume distributions of three porous adsorbents, silica alumina (steam deactivated), silica gel (Davidson 59), and silica gel (Mallinc-krodt Standard Luminescent), are calculated. The results are compared with those obtained by the previous method in which surface tension is taken as constant and also with the others. obtained by the modelless method proposed by Brunauer et al. The maximum point of the distribution curve shift to the larger pore radius, when the curvature dependency is considered. Furthermore, the relative pressure at which capillary condensation commences is by far the lower than that accepted previously. This effect becomes significant as the pore radius approaches to the micropore range.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.4
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• pp.103-116
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• 1990

The mixed mode surface crack in finite-width plate subjected to uniform shearing has been analyzed in 3-D problem by using boundary element method. The calculations were carried out for the surface crack angles (${\alpha}$) of $0^{\circ}, 15^{\circ}, 30^{\circ}, 45^{\circ}, 60^{\circ}, and 75^{\circ}, $ and for the aspect ratio(a/c) of 0.2, 0.4, 0.6 and 1.0 to get stress intensity factors at the boundary points of the surface crack. For the aspect ratio of 1.0 and the surface crack angles, finite element method was used to check the results in this in this study. Comparison of the results from both method showed good agreement.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.4
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• pp.117-129
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• 1990

The mixed mode surface crack in finite-width plate subjected to uniform shearing has been analyzed in 3-D problem by using boundary element method. The calculations were carried out for the surface crack angles (${\alpha}$) of $0^{\circ}, 15^{\circ}, 30^{\circ}, 45^{\circ}, 60^{\circ}, and 75^{\circ}, $ and for the aspect ratio(a/c) of 0.2, 0.4, 0.6 and 1.0 to get stress intensity factors at the boundary points of the surface crack. For the aspect ratio of 1.0 and the surface crack angles, finite element method was used to check the results in this in this study. Comparison of the results from both method showed good agreement.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.65-72
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• 1993

A numerical method for nonlinear free-surface-wave problem is developed in this paper. The final goal of this study is to simulate the towing tank experiment of a ship model and to partially replace the experiment by the numerical model. The exact problem in the scope of potential flow theory is formulated by a variational principle based on the classical Hamilton's principle. A localized finite element method is used in the present numerical computations which made use of the following two notable steps. The first step is an efficient treatment of the numerical radiation condition by using the intermediate nonlinear-to-linear transition buffer subdomain between the fully nonlinear and linear subdomains. The second is the use of a modal analysis in the final stage of the solution procedures, which enables us to reduce the computation time drastically. With these improvements the present method can treat a much larger computational domain than that was possible previously. A pressure patch on the free surface was chosen as an example. From the present computed results we could investigate the effect of nonlinearity on the down-stream wave pattern more clearly than others, because much larger computational domain was treated. We found, specifically, the widening of the Kelvin angle and the increase of the wave numbers and the magnitude of wave profiles.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.5-11
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• 2022

Despite the increasing importance of manufacturing and application R&D for ultrapure deionized water and electrolyzed ion water, various and systematic studies have not been conducted until now. In this study, the electrostatic discharge (ESD) behavior of electrolyzed ion water using a proton exchange membrane(PEM) was evaluated according to the type, flow rate, and bubble of electrolyzed ion water. In addition, by observing that Oxidation Reduction Potential (ORP) value returns to the unique value of electrolyzed ion water after electrostatic discharge, the possibility of two types of ions participating in electrostatic discharge ((H₂O)_n⁺ (assumed)) and ions for maintaining the characteristics of electrolyzed water could be inferred. In order to confirm the chemical structure and characteristics of the cations, in-depth research related to water molecular orbital energy or band gap should be followed.

• Journal of Digital Convergence
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• v.10 no.3
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• pp.71-78
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• 2012

In this study, we tried to find the moderating effect as an interaction between brand concept variables and thinking style variables as well as the main effect of each. To this end, the inner wear bradns, CalvinKlein(symbolic concepts) and bodyguard(functional concept), as two parent brands and wallets as an extension product were selected. The results of this study were as follows: (i) Extension evaluation as well as fit judgement based on brand concepts was higher in symbolic brand than functional brand. (ii) The holistic thinkers were higher in fit judgement and expansion evaluation than the analytic ones. (iii) In case of symbolic brand, there was little differences in fit judgement and expansion evaluation between holistic thinkers and analytic thinkers. But In functional brand, there was some differences relatively. So, we found the interaction effect between variables in fit judgement and expansion evaluation. We can expect this research result to be helpful in working out diverse and practical marketing strategies using existing brand concepts in the global market environments.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1592-1602
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• 1990

Mixed mode surface crack in finite-width plate subjected to uniform tension and bending has been analyzed in 3-D problem by using boundary element method. The calculations were carried out for the surface crack angles(.a/pha.) of 0.deg., 15.deg., 30.deg., 45.deg., 60.deg., and 75.deg., and for the aspect ratio(a/c) of 0.2, 0.4, 0.6 and 1.0 to get stress intensity factors at the boundary points of the surface crack. For the aspect ratio of 1.0 and the surface crack angles, finite element method was used to check the results in this study. Comparison of the results from both methods showed good agreement.