• Journal of Electrochemical Science and Technology
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• v.10 no.4
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• pp.408-415
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• 2019

Electroplating is a widely used surface treatment method in the manufacturing process of electronic parts and uniformity of the electrodeposition thickness is very crucial for these applications. Since many variables including fluid flow influence the uniformity of the film, it is difficult to conduct efficient research only by experiments. So many studies using simulation have been carried out. However, the most popular simulation technique, which calculates secondary current distribution, has a limitation on the considering the effects of fluid flow on the deposition behavior. And modified method, which is calculating a tertiary current distribution, is limited to a two-dimensional study of simple shapes because of the massive computational load. In the present study, we propose a new electroplating simulation method that can be applied to complex shapes considering the effect of flow. This new model calculates the electroplating process with three steps. First, the thickness of boundary layers on the surface of the cathode plane and velocity magnitudes at the positions are calculated from the simulation of fluid flow. Next, polarization curves of different velocities are obtained by calculations or experiments. Finally, both results are incorporated into the electroplating simulation program as boundary conditions at the cathode plane. The results of the model showed good agreements with the experimental results, and the effects of fluid flow of electrolytes on the uniformity of deposition thickness was quantitatively predicted.

• The KIPS Transactions:PartD
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• v.11D no.3
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• pp.649-658
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• 2004

An object-oriented system is organized by a set of interacting objects and the system behavior is represented by the cooperating interaction bet ween objects. The characteristics of object-oriented software. such as inheritance and polymorphism, increase the difficulty of the object-oriented software testing. At running time of a program, one call from a member function can bind to other member functions because of the dynamic characteristics such as concurrence, dynamic binding and interaction. Therefore, there need the research about considering the characteristics of object-oriented software and concurrently testing the interaction between objects. In this paper, we propose the techniques as follows. First, we construct a flattened state chart diagram by considering the inheritance and polymorphism. Next, we model the system with CPN(Colored Petri Net) that usually is applying the system modeling and simulation. Last, we propose a test case generation techniques for testing the interaction between objects in object-oriented software by applying a Design/CPN tool.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.9
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• pp.940-951
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• 2012

This study evaluates the fit preference of the tailored jacket according to body types for 20's adult women through a comparison of real and virtual fit. A five point fit evaluation scale utilizing a wearer acceptability scale by Shen and Huck was used to evaluate the degree of the preference of real and virtual fit. This scale contained 23 items in three categories: front fit, back fit, and side fit. For each item, 5 responses from 'too tight' fit (1 point) to 'too loose' fit (5 point) were possible. The middle position for each fit criterion indicated a 'good' fit (3 point). The data were analyzed with a t-test using statistical program SPSS 17.0. According to the results, there were no significant differences ($p{\leq}.05$) between the real and virtual fit preference in total measurement items such as front collar, lapel and roll line, front shoulder slope, front armhole, front waist, abdomen, sideseam, hemline, front silhouette, side shoulder, side armhole, side sleeve width, side hip, side silhouette, back collar stand, upper back, back armhole, back waist, back hip, back silhouette except front bust, side waist, and back center back. The factor that caused a difference in the fit preference between the real and virtual fit evaluation was a specific body type such as Body Type A that indicated a small bust circumference and a big hip circumference.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.64-71
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• 2013

In this study we designed a lean $NO_x$ trap (LNT) model with $GT-POWER^{TM}$ program and then the LNT model was compared to the bench flow reactor test results. This model consists of 9 kinetic reactions to represent the main steps of NO oxidation, $NO_x$ adsorption, $NO_x$ release and then its reduction. The comparison was performed on the operating conditions at the space velocity of 50,000 1/hr and 80,000 1/hr with the temperature range of $200^{\circ}C{\sim}500^{\circ}C$ with the even spaced temperature step of $50^{\circ}C$. The experimental results show that the $NO_x$ conversion efficiency was enhanced by the temperature up to $350^{\circ}C$ and then decayed at higher temperatures. The LNT model predicts the similar trend of the $NO_x$ conversion efficiency to the experimental results below $350^{\circ}C$, but overestimates above $350^{\circ}C$. This overestimation comes from the higher reduction efficiency which was obtained by the different reduction gas composition such as $C_3H_6$ in the model to replace $CH_4$, $C_2H_4$ in the bench test.

• The Journal of Korean Association of Computer Education
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• v.8 no.6
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• pp.1-12
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• 2005

IT education in the colleges or universities and IT industry in producing IT manpower are urgently called for to balance its supply and demand. To correct this problem, Ministry of Information and Communication launched a program where demand-oriented curriculums are developed and applied to colleges. This paper proposes a design technique based on meta-model and software development process in developing curriculums and courses. This meta-modeling technique is proven to result in the extendibility, flexibility and quality improvement in software design. Therefore, we expect that proposed technique makes it possible to be improved in quality.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.443-453
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• 2011

The purpose of present study is to develop a noise map around Korean Train Express (KTX) line. It is also to evaluate the high speed railway noise influence in neighboring areas around KTX. In order to develop the noise map, noise source modeling and 3-D noise radiation simulation have been performed by means of SoundPLAN program. The result of the noise map has been verified in comparison with the measured noise level. Noise measurements have been performed at 15 locations around KTX line. At each locations, 6 microphones were located 1.5m and 3m above the ground at each of 25m, 50m and 75 m distances from a center of the KTX track. The noise map showed clearly the high speed railway noise influence in neighboring areas around KTX line. The present study has also showed the noise could be reduced by using noise barriers constructed at severely noise-exposed locations.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.3
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• pp.346-352
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• 2010

Recently, the high-tech industries, such as the aerospace industry, the auto industry, and the electronics industry, are growing up considerably. Because of that, high machining accuracy and productivity of precision parts have been required. The tooling system is important part in the machining center. HSK tooling system is more suitable than BT tooling system for that of high speed machining center. It is because static stiffness and machining accuracy of HSK tooling system are higher than those of BT tooling system. In this paper, static and dynamic behavior of the HSK tooling System is analyzed according to bearing characteristics and lightweight parts. In order that, three different models of the HSK tooling system are modelled by using a 3D modeling/design program. More stable one in the models of HSK tooling system can be selected by using the FEA(Finite Element Analysis).

• Nuclear Engineering and Technology
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• v.34 no.3
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• pp.242-249
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• 2002

The relationship between the tritium release rate from the nuclear power plant and tritium concentration in the environment around the Kori site was modeled. The tritium concentration in the atmosphere was calculated by multiplying the release rates and $\chi$/Q values, and the d3V deposition rate at each sector according to the direction and the distance was obtained using a dry deposition velocity. The area around Kori site was divided into 6 zones according to the deposition rate. The six zones were divided into 14 compartments for the numerical simulation. Transfer coefficients between the compartments were derived using site characterization data. Source terms were calculated from the dry deposition rates. Tritium concentration in surface soil water and groundwater was calculated based upon a compartment model. The semi-analytical solution of the compartment model was obtained with a computer program, AMBER. The results showed that most of tritium deposited onto the land released into the atmosphere and the sea. Also, the estimated concentration in the top soil agreed well to that measured. Using the model, tritium concentration was predicted in the case that the tritium release rates were doubled.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.12 s.255
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• pp.1518-1525
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• 2006

Finite element analyses of structures made of the fiber reinforced composites require an adequate method to characterize the high anisotropic behavior induced by one or several layers of fiber cords with different spatial orientation embedded in a rubber matrix. This paper newly proposes a continuum based rebar element considering change of the orientation of the fiber during deformation of the composite. The mechanical behavior of the embedded fiber is modeled using two-node bar elements in order to consider the relative deformation and spatial orientation of the embedded fiber. For improvement of the analysis accuracy, the load-displacement curve of fiber is applied to the stiffness matrix of fiber. A finite element program is constructed based on the total Lagrangian formulation considering both geometric and material nonlinearity. Finite element analyses of the tensile test are carried out in order to evaluate the validity of the proposed method. Analysis results obtained with the proposed method provides realistic representation of the fiber reinforced rubber composite compared to results of other two models by the Halpin-Tsai equation and a rebar element in ABAQUS/Standard.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.6
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• pp.579-586
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• 2010

Due to the recent development of measuring technology and 3D programs, it has become possible to obtain various spatial data. This study utilizes the 2-dimensional data and 3-dimensional data extraction technology based on the existing empirical and statistical DB. The data obtained from geospatial data technology are integrated with civil engineering BIM to conduct the modeling of the topography of the target region and select the optimum location condition by using the cut and fill balance of the volume of earth. The target area is the land around Tamjin River, Jangheong-gun, Jeolla-do. The 3-dimensional topology linked with 3-dimensional mapping technology by using the orth-image and aerial LiDAR that uses aerial photo of the target area is visualized with Civil3D of AutoDesk. By using Civil3D program, the Thanks to the recent development of measuring technology and 3D programs, target area is analyzed through visualization and related data can be obtained for analysis. The method of using civil engineering BIM enables to obtain various and accurate information about the target area which is helpful for addressing the issues risen from the existing methodology. In this regard, it aims at searching for the alternatives and provides suggestions to utilize the information.