• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.9-17
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• 2015

Interface behavior of concrete-infilled steel tube (CFT) was investigated based on the experimental observations and numerical analyses. Laboratory tests were performed for twelve CFTs that consisted of two different cases of diameters where each diameter case was composed of three different cases of shear span length. Thereby, diameter and shear span parameters were considered to prove the question of whether there exists interface slip between steel tube and infilled-concrete. Confining effect of steel tube to infilled concrete was also investigated by measuring lateral strain as well as longitudinal strain. Based on the study, it was concluded that confining effect of steel tube to infilled-concrete is not influential under flexural loading and therefore, the sectional analysis is an effective way to estimate the flexural strength of CFT.

• Korean Institute of Interior Design Journal
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• v.25 no.1
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• pp.201-212
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• 2016

This study is a literature study aimed to derive the evaluation factors for the survey of housing satisfaction of the physically handicapped. To attain the objective, the present study compared the influential factors of housing satisfaction for normal people and those for the physically handicapped found in the precedent researches, and analyzed them to draw out the evaluation factors for housing satisfaction of the physically handicapped. And then it drew out sub-factors and elements for the housing satisfaction of the physically handicapped. The evaluation factors for housing satisfaction of the physically handicapped are divided mainly into physical, social-psychological and economic factors. First, physical factor consists of 'functionality (usability)', 'safety', 'convenience', 'comfort', 'aesthetics', 'accessibility (mobility)', 'identifiability (recognition)'. Of them, 'functionality (usability)' factor consists of 3 sub-factors and 8 elements. 'Safety' was subdivided into securing safety and public order/crime prevention. and structural safety, and 7 elements were drawn out from 'safety'. 'Convenience' is sub-categorized into convenient usage and simple operation, and 9 elements were derived. 'Comfort' was classified into 2 sub-factors and 9 elements. 'Aesthetics' was classified into 2 sub-factors and elements. 'Accessibility (mobility)' was divided into 2 sub-factors and elements. 'Identifiability (recognition)' was classified into 2 sub-factors and 5 elements. Second, social-psychological factor includes 'sociality' and 'independence' factor. One sub-factor and one element were drawn from each of both factors. Third, 'economic factor' consists of 'economy'. One sub-factor and elements were drawn out from the factor. It is expected that the 10 evaluation factors, their sub-factors and elements that have been derived from this study can be used as the basic data and/or reference in designing residential space for the physically handicapped and making policy for it after verifying them in following studies. The present study finds itself significance in that the findings here can ultimately improve the housing welfare and life quality of the physically handicapped.

• Journal of the Korean Institute of Gas
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• v.10 no.3 s.32
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• pp.34-40
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• 2006

This paper presents the optimized design of O-rings with a rectangular groove and dovetails, which are strongly related on the sealing performance of LPG filling unit. The computed results on the optimal design are analyzed by non-linear MARC finite element program with Taguchi method. O-rings with 4 different groove models are analyzed for 3 different elastomeric materials. The design parameters are given to polymer materials, groove depth, groove width, and diameter of O-rings. The FEM computed results showed that the affection ratios of O-ring diameter and material property are the most influential parameter among the groove width, groove depth, and compression ratio. Thus, this paper recommends model III for a rectangular groove and model IV for a dovetail groove with a given gas supply pressure of 1.764 MPa.

• Journal of Korean Society of Steel Construction
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• v.20 no.3
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• pp.389-398
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• 2008

The current design practice of electric transmission tower is based on the allowable stress design. However, it is difficult to find the cause behind a transmission tower's collapse by the above design approach as the collapse is caused by large secondary deformations based on and geometrical nonlinear behavior.influence factor for the nonlinear behavior is mainly residual stress, initial imperfection and end restraints on members. In this study, the necessity of the nonlinear analysis is examined through the comparison between elastic ana the nonlinear analysis, a new analytical method (equivalent nonlinear analysis technique) is proposed. To confirm the reliability of the proposed method, the computed ultimate load of the transmission tower using the method was compared with that of the nonlinear finite element analysis. Effects of parameters, such as compressive force and the slenderness ratio of the brace member on the main post member, were investigated. The effective member length according to influential parameters was formulated in table form for practical purposes.

• Tribology and Lubricants
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• v.29 no.1
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• pp.13-18
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• 2013

Slider bearing is a widely used load-carrying element in the industry. While a large number of studies have investigated the effect of overall surface curvature, very few have considered sinusoidal surface. Recently, consideration of surface roughness/waviness or intentional wave design has been identified as an important issue in the manufacture of hard disk driver, mechanical seal, hydraulic machine, and etc. This study investigated the load-carrying capacity of a finite-width slider bearing with a wavy surface. Film thickness ratios, length-width ratio, ambient pressure, amplitude, and partial distribution were selected as the simulation parameters. The calculation results showed that the load-carrying capacity rapidly varied at small film thickness ratio, but the waviness near the area of minimum film thickness made much more influence with an increase in film thickness ratio. As the length-width ratio of bearing was increased, ambient pressure became more influential at small film thickness ratios. Furthermore a particular partial distribution of the wavy area led to higher load-carrying capacity than did the whole distribution. Consequently, the results of this study are expected to be of use in surface micro-machining of finite-width slider bearings.

• Journal of Korea Game Society
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• v.13 no.3
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• pp.55-68
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• 2013

This study examined the factors determining experience of flow in mobile social network games. Built upon the literature on flow experience in the Internet and online games, this study classified the determining factors into three categories. The first category is the content factor which includes graphic design, challenge, and incentive; the second is the device factor including ease of access and ease of control; the third is the social factor including social interaction and community activities. A correlation analysis was conducted to examine the association between each of the seven determining factors and flow experience. Additionally, a hierarchical regression analysis was performed to evaluate which of the selected factors would exert a relatively strong influence on experience of flow. Both analyses reached the same conclusions as follows: Graphic design, incentive, and community activities increase flow experience while challenge and ease of control exert little influence on flow experience. In addition, graphic design was the most influential element in determining flow experience, followed by community activities and incentive, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.3
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• pp.474-485
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• 2008

The purpose of this study is to examine the determinants and elements to enhance Korean international competitiveness, employing Porter's(1998) Diamond Model. Half of the 500 leading apparel exporters that were members of the Korea Apparel Industry Association in 2003 were selected as the target of this research. From May to June of 2003, survey questionnaires were sent to executives of these 250 companies in person or by telephone, e-mail, or fax. Seventy questionnaires were used for the final data anlysis. The items used were Reliability, Categorical Regression, and Frequency, using SPSS 11.5. The results were as follows: First, as a result of analyzing the influence of international competitiveness in Korean apparel industry, the firm's strategy, structure, and rivalry was the most influential factor. Others were related and supporting industries, government, chance, demand conditions, and factor conditions. Also, the elements that affect Korean international competitiveness were listed as the level of price competition in foreign markets, the level of labor cost, export marketing capacity, and exchange fluctuation. The most important element to improve the international competitiveness of the Korean apparel industry was a demand growth rate of the overseas markets(Demand Conditions), followed by the level of the labor costs(Factor Conditions), the capability of internationalization(Firm Strategy, Structure, and Rivalry), the change of currency(Chance), the quality and management of products(Demand Conditions), the capability of planning products(Firm Strategy, Structure, and Rivalry), free trade from 2005(Chance), and global sourcing strategy(Firm Strategy, Structure, and Rivalry). Korea's main rival country in apparel related and supporting industry factors is China. However, Korea has a higher level of technology development, quality, and price level than China.

• The Journal of Korean Association of Computer Education
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• v.18 no.5
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• pp.45-54
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• 2015

There has been rising demand within the South Korean government and among various industries in recent years on the need for strengthening the competitiveness of the software industry, which they highlight as being a core element for national competitiveness. This strategy would require enhancing the job competency of software developers. This study's results show that computational thinking (CT), which is one of the more creative solutions to the problem, has a positive effect on the enhancement of software developers' job competency. Furthermore, the study finds that the software development tasks of simulation, algorithms and procedures, and parallelization (in that order) serve as influential elements for software developers, which differs from previous studies' findings. The South Korean government thus should emphasize education in these areas in order to enhance the nation's job competence. Because simulation, especially, has the greatest influence among these areas, there is a particular need to strengthen that area.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.7
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• pp.7-16
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• 2000

This paper reports a methodology and its application for extracting cell capacitances and parasitic capacitances in a stacked DRAM cell structure by a numerical technique. To calculate the cell and parasitic capacitances, we employed finite element method (FEM), The three-dimensional DRAM cell structure is generated by solid modeling based on two-dimensional mask layout and transfer data. To obtain transfer data for generating three-dimensional simulation structure, topography simulation is performed. In this calculation, an exemplary structure comprising 4 cell capacitors with a dimension of $2.25{\times}1.75{\times}3.45{\mu}m^3$, 70,078 nodes with 395,064 tetrahedra were used in ULTRA SPARC 10 workstation. The total CPU time for the simulation was about 25 minutes, while the memory size of 201MB was required. The calculated cell capacitance is 24.34fF per cell, and the influential parasitic capacitances in a stacked DRAM cell are investigated.

• Journal of Korean Society of Transportation
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• v.27 no.6
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• pp.45-53
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• 2009

This study presumes the efficiency of each route by utilizing data of Seoul's exclusive bus routes for the 2008 and the DEA model. In the estimation, it is assumed that the number of passengers and profits of each route is calculated by considering the number of buses and stops, travel distance, intervals and management cost. This study computed the efficiency scores of each bus line in Seoul based on the data for the first half of 2008 and one of the DEA models, namely the BCC model. After analysis using the input-oriented BCC model, out of a total of 18 lines of interest, there were 2 CRS lines and 16 IRS lines. Also, the Tobit Regression Analysis that helps identify the impact of the elements used in the analysis on efficiency scores proved that the most influential element to exclusive buses is the length of intervals.