• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.137-147
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• 2010

The purpose of this study is to research a method of creating a new type of boundary by repeated disposition of single unit of modularized membrane successively. In the contemporary architectural indoor space, more highly dimensional analysis of boundary is required and the necessity of establishing boundary of a new concept that may satisfy cultural value, social value and artistic value as a whole as well as aesthetic and functional merit has been increased. In order to create a membrane that may fulfil the requirements of the diversified programs of space like this, an approach of complicated mechanism and high-dimensional calculation are required. At this time, digital GA modelling, parametric modelling technique may expand its range of possibility. One thing to be noted at this juncture is that indefinite expandability involved in digital modelling technique, modelling by grid of absolute and relative coordinates and convenience of systematization may surpass limitation of analogue or simple numerical calculation being progressed in the past. And in order to create solid process including unit modelling or pattern formation, Precise calculation process of computer is necessitated inevitably.

• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.53-69
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• 2024

The solubility of Cloxacillin sodium in ethanol, 1-propanol, isopropanol, and acetone solutions was measured at different temperatures. The melting property was also tested by using a differential scanning calorimeter (DSC). Then, the solubility data were fitted using Apelblat equation and λh equation, respectively. The Wilson model and NRTL model were not utilized to correlate the test data, since Cloxacillin sodium will decompose directly after melting. For comparison purposes, the four empirical models, i.e., Apelblat equation, λh equation, Wilson model and NRTL Model, were evaluated by using 1155 solubility curves of 103 solutes tested under different monosolvents and temperatures. The comparison results indicate that the Apelblat equation is superior to the others. Furthermore, a new method (named the calculation method) for determining the Apelblat equation using only three data points was proposed to solve the problem that there may not be enough solute in the determination of solubility. The log-logistic distribution function was used to further capture the trend of the correlation and to make better quantitative comparison between predicted data and the experimental ones for the Apelblat equation determined by different methods (fitting method or calculation method). It is found that the proposed calculation method not only greatly reduces the number of test data points, but also has satisfactory prediction accuracy.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.46-53
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• 2008

Recently, the synthetic material stern tube bush has been applied by ship owner's requirement because the synthetic material has a merit. That is to say, when stern tube seal is damaged and sea water comes into stern tube, it can work without problem because of water lubricating property. However, the material also has a demerit of temperature rise problem when some factors meets on synthetic material, for example, not sufficient lubrication oil supply and not proper shaft alignment and so on. As known in the world, the RAILKO bush is rampant for synthetic material by some ship owner because of the above mentioned reason. However, the bush has several accidents on large container vessel. Unfortunately or fortunately our yard has a chance to apply the RAILKO bush owing to requirement of specific ship owner. Therefore, it is much more required to approach the accurate shaft alignment analysis. In line with this reason, we had a shaft alignment calculation considering hull deformation and hull flexibility (hull stiffness). Also, in the calculation, we had considered dynamic condition which is reflected he propeller thrust forces and moments and oil film stiffness on the shaft alignment calculation. According to he shaft alignment calculation, bearing slope was applied on the tern tube bush and was measured. The RAILKO bush should be applied the running in procedure according to maker's recommendation for performing the oil film on the bush surface. Finally, the vessels were delivered successfully without any problem with AILKO bush as shown on his paper.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.1 s.190
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• pp.57-63
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• 2007

Wire drawing process of the high carbon steel with a high speed is usually conducted at room temperature using a number of passes or reductions through consequently located dies. In the multi-pass drawing process, temperature rise in each pass affects the mechanical properties of the final product such as bending, torsion, and tensile property, etc. This temperature rise during the deformation promotes the occurrence of delamination, and deteriorates the torsion property and durability of wire. This study investigates the occurrence of delamination in the wire through the torsion test and the evaluation of wire temperature. The excessive wire temperature leads to the occurrence of the delamination. Based on the calculation of the wire temperature, a new pass schedule, which can prevent the delamination due to the excessive wire temperature rise, is designed through the isothermal pass schedule.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.576-578
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• 2000

This paper address the prediction method of a soil thermal property depending on soil moisture contents and suggests the guideline to determine the soil thermal resistivity for the calculation of the cuurent carrying capacity of underground power cables in Korea.

• Journal of applied mathematics & informatics
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• v.38 no.5_6
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• pp.579-590
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• 2020

The flatness property of a unilateral weighted shifts is important to study the gaps between subnormality and hyponormality. In this paper, we first summerize the results on the flatness for some special kinds of a weighted shifts. And then, we consider the flatness property for a local-cubically hyponormal weighted shifts, which was introduced in [2]. Let α : ${\sqrt{\frac{2}{3}}}$, ${\sqrt{\frac{2}{3}}}$, $\{{\sqrt{\frac{n+1}{n+2}}}\}^{\infty}_{n=2}$ and let W_α be the associated weighted shift. We prove that W_α is a local-cubically hyponormal weighted shift W_α of order ${\theta}={\frac{\pi}{4}}$ by numerical calculation.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.230-231
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• 2001

Silica glass is a core material for optical fiber in optical telecommunications, but its centrosymmetry eliminates the second order nonlinearity. But it is experimentally well known that the space charge polarization induces the Second Harmonic Generation (SHG) when a strong DC voltage is applied to silica glass for a long period time with metal blocking electrodes. In this research, a theoretical calculation of the nonlinear optical property caused by the space charge polarization is performed, and a model of a numerical analysis to predict the small change in nonlinear optical property as functions of time and space is provided.

• Journal of the Semiconductor & Display Technology
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• v.9 no.3
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• pp.71-74
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• 2010

In this study the optical properties, such as relative transmittance and reflectance of PDP were analyzed with 3D optical code. Because of the electrode structure, the reference model shows 21.3 % higher transmittance than the test model and the reference model shows 16.6 % higher reflectance than the test model. The calculated reflectance of reference and test models is compared to the measured reflectance and the difference between calculation and measurement is 4.9 %.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.43-46
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• 1991

Nd-Fe-B Permanent Magnet, which is recently more used, has some advantages in comparison with other permanent magnet. However, for the Nd-Fe-B has higher RTC(reversible temperature coefficient), property of the Nd-Fe-B magnet is changed by temperature rise. In this paper temperature rise of a disc type motor is calculated using a heat source network method.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.91-95
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• 2002

This study is using the RADIANCE lighting simulation tool to determine the transmittance where the horizontal blind is installed. The transmittance is applied to DayDim program which is a lighting calculation and analysis tool. Parameters such as clear sky type, seasonal changes(the summer solstice), altitude, azimuth and horizontal blind angle at a 0$^{\circ}$, 45$^{\circ}$, 90$^{\circ}$ were considered. The simulation results present that measured directional transmittances have different values according to each directional property of the horizontal blind.