• Journal of the Korean Society of Costume
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• v.55 no.5 s.95
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• pp.55-64
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• 2005

The concern with three-dimensional measurement has been growing in recent years. And over the last few years, several studies have been made on three-dimensional measurement. Some of the studies using a three-dimensional measurement have focused on type of form of human body and evaluation of fitness. But there has been no study about applications of three-dimensional measurement system for shape analysis. So, the purpose of this study was to investigate about application of three-dimensional mea-surement system lot shape analysis. The instrument and tools for three-dimensional measurement was Whole Body 3D scanner(model name: Exyma-WBS2H). Analysis program used in experiment is Rapid Form 2004 PPI (INUS technology, Int, Korea). The following results were obtained; 1. The point data using three-dimensional measurement system built 3D model. 2. The three-dimensional data were used to analyze length and curvature of shape. 3. The shape using three-dimensional measurement system could be used in variety field.

• Laser Solutions
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• v.14 no.2
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• pp.24-29
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• 2011

The design of a telecentric f-${\theta}$ lens with a field of view (FOV) $30^{\circ}$ and an effective focal length of 1000mm is presented. The optical stop is placed at the front plane and the design is based on a geometric ray tracing technique, and the designed system consists of a series of convex and concave lenses. The designed f-${\theta}$ lens showed a considerable reduction in weight with a simplified structure and resulted in a good performance in the designated FOV. Detail analysis of rays is also presented. 653nm (red laser), 586nm (green laser), and 468nm (blue laser) were simulated as a light source and image illuminating source. The developed optical design requires 7 pieces of lenses made of SF1, N-FK56, N-LAK33, and BK7 glass materials. With optimal parametric design, the effective focal length was calculated to be 974.839mm which is very close to the initial design target. For the manufacturing purpose, the dimensions of lens curvature and thickness were truncated with error ranging 0.1% to 3.2%. As a result, the overall error was calculated to be 3.2% which can be still tolerable for display, laser material, and machining processing.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1039-1044
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• 2008

By the result of efforts for the technology development of G7 trainset, the technology of domestic high-speed train KTX-II has lately been put to practical use while a forward countries of railway, which have their own developing ability of high-speed train, are competing against each other for the development of faster high-speed train system. Japan has been commissioning of FASTECH 360 which was developed in June 2005. Also France and Germany have been commissioning of next generation high-speed train such as AGV and ICE-3, developed basing on technology of their existing high-speed train system(TGV and ICE), its maximum commercial running speed is 360kph, and adopted multiple unit system. For the development of technology of domestic high-speed train and enhancement of national technology competitive power, HEMU (High-speed Electrical Multiple Unit) development project has been carried out as a national R&D project from last August. For the executing of HEMU's maximum speed test, we have investigated the high speed line characteristics (i.e. radius of curvature, gradient, cant etc.) of Seoul-Pusan line and Honam line which is under construction. We'd like to examine a study of condition for the best HEMU T&C line considering HEMU's characteristics (i.e. acceleration, deceleration etc.) and its interface with infrastructure in this paper.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.244-249
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• 1988

Some experiments were conducted to utilize the raphanus test as a bioassay method for plant growth regulaters and hormonal herbicides. Among seven radish cultivars, the response of Jangbaegminong was the most sensitive and quantitative to ${\alpha}$-NAA and its coefficient of variation value was the lowest. The optimum application time of test compounds was estimated seven to nine days after seeding. After ${\alpha}$-NAA treatment the curvature angle of radish cotyledonary petiols was sharply increased to the maximum value at 24 hours after and was changed by light and temperature conditions. The curvature response was observed by application of ${\alpha}$-NAA, phenoxy and indole compounds but often plant growth regulators, $GA_3$ benzyladenine, ABA and homobrassinolide was not detected by this method. So this bioassay was useful to evaluate the activity of a compound as an auxin or a hormonal herbicide.

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.27-35
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• 2012

In this paper, the frost heaving and thawing characteristics of flexible pavement structure were evaluated in the large scale freezer which have a specification of temperature range $-20^{\circ}C{\sim}10^{\circ}C$ and $3.2m(L){\times}3.2m(B){\times}2.4m(H)$ in size. The insulated steel box with the size of $0.9m(L){\times}0.9m(B){\times}0.9m(H)$ was used to simulate actual pavement road structure. The variation of temperature, frost heave amount and frost heave pressure were measured through the instrument of TDS-602 data logger. LFWD (light falling weight deflectometer) was used to determine the change of deflection due to the frost heaving and thawing. Furthermore, the influence of aggregate layer to the freezing of the subgrade soil was studied to verify the function and effectiveness of the anti-freezing layer.

• Corrosion Science and Technology
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• v.16 no.5
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• pp.257-264
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• 2017

Film of new Ti-15Zr-5Nb alloy formed during galvanic anodizing in orthophosphoric acid solution was characterized by optical microscope, scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and Raman micro-spectroscopy. Its anticorrosive properties were determined by electrochemical techniques. The film had a layer with nanotube-like porosity with diameters in 500-1000 nm range. The nano layer contained significant amounts of P and O as well as alloying element. Additionally, Raman micro-spectroscopy identified oxygen as oxygen ion in $TiO_2$ anatase and phosphorous as $P_2O_7{^{4-}}$ ion in phosphotitanate compound. All potentiodynamic polarization curves in artificial Carter-Brugirard saliva with pH values (pH= 3.96, 7.84, and 9.11) depending on the addition of 0.05M NaF revealed nobler behavior of anodized alloy and higher polarization resistance indicating the film is thicker and more compact nanolayer. Lower corrosion rates of the anodized alloy reduced toxicity due to less released ions into saliva. Bigger curvature radii in Nyquist plot and higher phase angle in Bode plot for the anodized alloy ascertain a thicker, more protective, insulating nanolayer existing on the anodized alloy. Additionally, ESI results indicate anodized film consists of an inner, compact, barrier, layer and an outer, less protective, porous layer.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.4
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• pp.441-448
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• 2004

A numerical study was conducted to show the effect of aspect ratio on the analogy of the developing laminar flows between in orthogonally rotating straight duct and in a stationary curved duct of rectangular cross-section. In order. to clarify the similarity of two nows, dimensionless parameters (equation omitted) and Rossby Ro= $w_{m}$$\Omega$ $d_{h}$, in a rotating straight duct were used as a set corresponding to Dean number, (equation omitted), and curvature ratio, λ=R/ $d_{h}$, in a stationary curved duct. Four. different aspect ratios A=0.25, 0.5, 2 and 4 were considered. Under the condition that the magnitudes of Ro and λ were large enough to satisfy the 'asymptotic invariance property' and the aspect ratio was larger than 1, there were strong quantitative similarities between the two flows such as flow patterns, friction factors, and maximum axial velocity magnitudes fur the same values of $K_{LR}$ and $K_{LC}$ . On the other hand, as the aspect ratio decreased below 1 (A=0.25 and 0.5), the difference of the secondary flow intensity between these two flows was enhanced and therefore the analogy of two flows was not so evident as that of the larger aspect ratio (A=2 and 4). 4).nd 4).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.11
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• pp.1225-1232
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• 2009

In this paper, a parabolic edge planar monopole antenna for indoor DTV reception is presented. The antenna has broadband property with the planar monopole and ground of parabolic edges. It is designed close to self-complementary structure as changing curvature of edges of monopole and ground. Monopole and ground conductors of the antenna are on the same plane, and excited through CPW feeding. It is fabricated on an FR4 dielectric substrate of $\varepsilon_r=4.4$, and the dimension is $40\;mm{\times}200\;mm{\times}1.6\;mm$. Return loss is larger than 10 dB in 470~806 MHz. Maximum gain is 1.86 dBi on E-plane at 810 MHz and 3.86 dBi on H-plane at 600 MHz.

• Structural Engineering and Mechanics
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• v.63 no.3
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• pp.269-280
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• 2017

One major concern that has occupied the mind of the designers is a structural failure as result of stress concentration in the geometrical discontinuities. Understanding the effective parameters contribute to stress concentration and proper selection of these parameters enables the designer get to a reliable design. In the analysis of perforated isotropic and orthotropic plates, the effective parameters on stress distribution around holes include load angle, curvature radius of the corner of the hole, hole orientation and fiber angle for orthotropic materials. This present paper tries to examine the possible effects of these parameters on stress analysis of infinite perforated plates with central quasi-square hole applying grey wolf optimizer (GWO) inspired by the particular leadership hierarchy and hunting behavior of grey wolves in nature, and also the present study tries to introduce general optimum parameters in order to achieve the minimum amount of stress concentration around this type of hole on isotropic and orthotropic plates. The advantages of grey wolf optimizer are stout, flexible, simple, and easy to be enforced. The used analytical solution is the expansion of Lekhnitskii's solution method. Lekhnitskii applied this method for the stress analysis of anisotropic plates containing circular and elliptical holes. Finite element numerical solution is employed to examine the results of present analytical solution. Results represent that by selecting the aforementioned parameters properly, fewer amounts of stress could be achieved around the hole leading to an increase in load-bearing capacity of the structure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.291-297
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• 2006

In this study, the equivalent physical properties of the shielded slot plate having a lot of very tiny bridge shape structures on its plane were determined by tensile tests and structural analyses. With those results, numerical analyses for the deflection profile by gravity effect were carried out to compare with experimental results. The two results were shown coincident very well so that the estimated equivalent physical properties were verified enough for further studies such as curvature reduction for the shielded slot plate.