• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3A
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• pp.145-152
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• 2011

Current Bridge Specification for Highway Bridges adopts a simplified method to determine sectional forces of abutment wing by dividing its area into four sections. This simplified method was developed in Japan when numerical analysis was not mature and computer resources were expensive. This simplified method has been with us without modification. This study evaluates the problem of current design practice to improve the design guideline for abutment wing. In this study, a finite element model of abutment wing based on shell elements was developed to obtain accurate sectional force. In addition, foreign design specifications regarding abutment wing were thoroughly examined. It has been observed that sectional forces obtained from the simplified method produce inaccurate results under various geometric shapes. Thus, it is recommended that two dimensional plate analyses should be adopted for future design of abutment wing wall.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.7
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• pp.721-727
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• 2010

The spontaneous ignition of coal stockpile causes serious safety and economic problems. Such spontaneous ignition occurs in coal stockpile when the rate of heat released by the oxidation of coal is greater than the rate of heat lost to the surroundings. In this study, a two-dimensional unsteady model is adopted for studying spontaneous ignition and the numerical results are compared with experimental results. The numerical results are in a good agreement with the experimental ones. Depending on the porosity, the internal maximum temperature, pressure, and oxygen mass fraction during spontaneous ignition are investigated. On the basis of the numerical results, the transient temperature variations for several shapes of coal stockpiles are analyzed. Further, the physical mechanisms of hot-spot formation and spontaneous ignition are analyzed.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1001-1010
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• 1998

The purpose of this study was to investigate the images and characteristic formative elements of Korean traditional patterns. The Korean pattern image could be interpreted into visual elements of design based on the images, the characteristic formative elements of Korean traditional patterns, and their relationships. Fourteen patterns selected from 5 groups of Korean patterns were used as stimuli. An image evaluation using a 2-point sementica scale of 19 bipolar adjectives, and an impression evaluation of which results were presented by visual drawing using lines and shapes were carried out. The data were analyzed by correspondence analysis and cluster analysis. The major findings are as follows; 1. Fourteen patterns and 19 adjectives were marked on a perception map composed of two (x and y-) axes. The bipoles of x- and y axes were soft-hard and splendid-artless, respectively. 2. Four clusters semerged to account for the dimensional sturucture of 14 patterns and 19 adjectives. These were splendid image, soft image, individualistic image, and sophisticated image. However there was no pattern which belonged to the cluster, sophisticated image. The Korean pattern image was founded to be better related to the kind of patterns than the type of patterns. 3. The characteristic formative elements obtained from the impression test were contour of motif, repeated line or shape, various curved lines, and decorative elements. 4. The splendid image was related to Bongwhang patterns and detailed line and complexity. The individualistic image was related to the abstractive form of Bongwhang pattern and the decorative form of Cloud pattern both of which have the characteristics of point-symmetry and abstraction, and Turtle-back pattern. In this case, the related charac-teristic formative element was identified to be repeated lines. The soft image was related to Moran, Cloud, and Taegeuk patterns. The related characteristic elements were various types of curved lines, decorative elements, and rounded contours.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.2
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• pp.121-132
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• 2016

This study proposes an approach for simulating high spatial resolution satellite images acquired under arbitrary sun-sensor geometry using existing images and 3D (three-dimensional) data. First, satellite images, having significant differences in spectral regions compared with those in the simulated image were transformed to the same spectral regions as those in simulated image by using the UPDM (Universal Pattern Decomposition Method). Simultaneously, shadows cast by buildings or high features under the new sun position were modeled. Then, pixels that changed from shadow into non-shadow areas and vice versa were simulated on the basis of existing images. Finally, buildings that were viewed under the new sensor position were modeled on the basis of open library-based 3D reconstruction program. An experiment was conducted to simulate WV-3 (WorldView-3) images acquired under two different sun-sensor geometries based on a Pleiades 1A image, an additional WV-3 image, a Landsat image, and 3D building models. The results show that the shapes of the buildings were modeled effectively, although some problems were noted in the simulation of pixels changing from shadows cast by buildings into non-shadow. Additionally, the mean reflectance of the simulated image was quite similar to that of actual images in vegetation and water areas. However, significant gaps between the mean reflectance of simulated and actual images in soil and road areas were noted, which could be attributed to differences in the moisture content.

• Journal of Digital Convergence
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• v.16 no.1
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• pp.351-356
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• 2018

The aim of this study is to propose guidelines for bus-stop information design that is more congested with the advent of U-Shelter, via case studies and focus group interviews. First, the literature research explored the concept of information design and correlation of information design and route map. Second, raising problems and consider improvement plans through case study in korea, overseas. Finally, current information design was evaluated and user's requests were derived through focus group interview. The current information design had problems with lack of priority, information overlaying, and hard recognition. Priority shall be selected by bus route, direction of bus, arrival time, interval, and operating time, and information overlay can be reduced into one. Also visualize the connection and direction between the lines using schematic and two-dimensional lines and shapes for recognition. Through this study, it will be used as a reference material to help improve and develop the bus-stop information design.

• The Journal of the Acoustical Society of Korea
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• v.33 no.6
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• pp.358-365
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• 2014

When a ship propeller having wing type sections rotates at high speed underwater, local pressure on the blade decreases and various types of the cavitation inevitably occur where the local pressure falls below the vapor pressure. Fundamentally characteristics of the cavitation are determined by the shapes of the blade section and their operating conditions. Underwater noise radiated from a ship propeller is directly connected to the occurrence of the cavitation. In order to design low noise propeller, it is preferentially demanded to figure out key features: how the cavity is generated, developed and collapsed and how the effect of viscosity works in the process. In this study, we first perform inviscid analysis of the partial cavity generated on two dimensional hydrofoil. Secondly, viscous analysis using FLUENT with different turbulence and cavitation models are presented. Results from both approaches are also compared and estimated.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.5
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• pp.61-66
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• 2010

A stereo vision, which is based on two or more images taken from different view points, is able to build three dimensional maps of its environment having various applications including robots and home networks. SAD algorithm, which is based on area-based correlation, is widely used since its regular structure provide abundant parallelism. In this paper, we present heuristic designs of SAD algorithm to meet the demands on accuracy and resource usages in various applications. The disparity abridgement and the window abridgement algorithms can be used for vision systems in low cost and small size. The window shape algorithm can be applicable when object are in specific shapes. The adaptive window algorithm work well when accuracy is the primary concern.

• KIEAE Journal
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• v.12 no.3
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• pp.41-46
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• 2012

The building envelope is important specially for saving energy consumption of residential buildings. but Apartment houses in Korea commonly have inside insulation system which have constantly arisen thermal bridges, the risk of heat loss, as a necessity. This study aims to evaluate integrated insulation performance according to the different shapes of external walls, adjacent to windows. The thermal performance analysis was carried out by Equivalent U-value and using the three-dimensional heat transfer computer simulation (TRISCO-RADCON), under nine different cases of comparing among three each of different bases(current standard model, 30percent energy saving model and 60percent energy saving model). The heating and the cooling load were also compared between two cases (standard U-value and Equivalent U-value) of three each of different bases, using the Building energy simulation which is based on DOE-2.1 analysis. As results, it turns out that if the Equivalent U-value is considered on the envelope analysis, the heat flow loss will be increasing more than the standard U-value, and if heat insulation property of the residential building reinforced rather than current, the rate of influences on the thermal bridges would be extremely expanded. In addition, it is shown that annual heating loads of the apartment house with applied Equivalent U-value substantially increased by more than 15 percent compared to those with the existing U-value, but annual cooling loads were negligibly affected.

• Archives of design research
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• v.12 no.2
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• pp.43-50
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• 1999

The purpose of this study is to suggest the standard size of a bench in the park. To obtain the basic shapes and size of a bench in the park, several parks are selected as a sample which is located in 6 major cities in Korea. Those obtained basic data of a bench are compared to standard size of a bench in United State and Japan and then human engineering concepts are applied to determine the optimal standard size. Furthermore the standard size of a bench is suggested in two classifications. One for the adults and the other for the children. This study is limited to a determining the standard size of a bench but in the future study, overall facilities in the park for the human being ha<> to be examined.

• Communications for Statistical Applications and Methods
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• v.17 no.6
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• pp.917-925
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• 2010

The canonical correlation biplot is a 2-dimensional plot for graphically investigating the relationship between two sets of variables and the relationship between observations and variables in the canonical correlation analysis. Recently, Choi and Choi (2008) suggested a method for investigating the relationship between skill and competition score factors of KLPGA players using this biplot. Choi et al. (2010) used this biplot to analyze the player characteristic factors and competitive factors of tennis Grand Slam competition. Moreover, Huh (1999) provided a generalized canonical correlation analysis and biplot for more than three sets of variables. A Procrustes analysis is a useful tool for comparing shapes between configurations. This study will provide a method to investigate the relationship between physique, physical fitness and basic skill factors of tennis players in the Korea Tennis Association using a generalized canonical correlation biplot and Procrustes analysis.