• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.353-362
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• 2000

Herringbone groove journal bearing (HGJB) is developed to improve the static and dynamic performances of hydrodynamic journal bearing. In this study, static and dynamic compressible isothermal lubrication problems are analyzed by the finite element method together with the Newton-Raphson iterative procedure. This analysis is introduced for prediction of the static and dynamic characteristics of air lubricated HGJB for various bearing configurations. The bearing load characteristics and dynamic characteristics are dependent on geometric parameters such as asymmetric ratio, groove depth ratio, groove width ratio and groove angle.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.81-96
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• 2019

The study intends to seek the creative ideas that can satisfy the needs of individual consumers by rediscovering the modern meaning and the artistic value of geometric ornaments engraved on the backside of Danyugyung, which is a traditional Korean pattern. In terms of the study method, the symbolic meaning and formative characteristics of Danyugyung were determined, and the form of its pattern and the geometric characteristics were analyzed. Based on this, Photoshop and illustrations were used to apply the shapes of Danyugyung and internal patterns to the textile designs, and the results are as follows. Firstly, it was found that Danyugyung was associated with the bronze mirror, which was used from the Bronze Age to the Early Iron Age, and was the product of artistic activities and an object and acted as a shamanistic and authoritative symbol of the ruling parties, which were responsible for the acts related to the spiritual world. Secondly, it was discovered that forms of Danyugyung were classified into Jomungyung and Semungyung in accordance with Forms of Danyugyung (造飾), and the formative features of the geometric ornaments that were engraved in great detail on the backside could be found in the images which change according to the form of the inner patterns. Thirdly, with regard to the development of the textile designs utilizing the shape and inner patterns of Danyugyung based on the formative features, it was could discover that the simple shape of Danyugyung presented a value which can be applied as a unique design factor delivering a visual rhythm by attempting to create various harmonies overlapping lines engraved on the inner patterns and the shapes of Danyugyung. Based on the above-mentioned outcomes, the possibility was confirmed that Danyugyung can be used as a novel motif and as a standard unit of patterns for textile design. With future studies, I would like to utilize the unique and diverse images as pattern motif for textile design.

• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.399-406
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• 2019

This study aims to find geometric parameters that the radiologist can change from time to time to reduce dose in angiography examinations. Depending on the geometric characteristics, the values calculated by effective dose were compared, while filming in fluoroscopy mode and Digital subtraction angiography, respectively. The study found that the lower the dose was in FPS mode, the lower the dose was reduced to 30-40%. Doses according to the X-ray angle were measured highest in AP View and lower as the angle went in the head direction. The greater the FOV, the higher the dose was 1.2-1.6 times, and the closer the distance between the X-ray tube and the table, the greater the dose was about 10%. Source-image intensifier distance (SID) get longer to 100 mm, dose of each fluoroscopy and Digital subtraction angiography increase up to 25-30%. In conclusion, various geometric characteristics in angiography examinations are parameters that can be applied by radiographers as frequently as possible, and appropriate geometric properties can be considered and applied in various situations, resulting in appropriate dose reduction.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.1
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• pp.155-167
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• 2021

The latest innovation in the field of fashion comes in the form of 3D-printed clothing. This study explores the composition and characteristics of the shapes in the architecture of Zaha Hadid, a representative architectural designer who expresses space in three dimensions. Hadid applies his aesthetic to fashion design using these distinctive geometric shapes to create design motifs as well as develop new clothing material with 3D printing technology. The research was conducted as follows. First, the lines and arrangement of the geometric shapes in Zaha Hadid's architecture were analyzed so that his design principles could be used as a theoretical basis for this study. The study also reviewed geometric fashion designs using 3D printing technology over the last ten years. Second, we developed triangular modules with rods and tongs that could be fashioned into clothing using fused deposition modeling (FDM) 3D printers. Lastly, the 3D printing fashion design was developed to explore new silhouettes, textures, and a novel way of producing clothing. This study hopes to serve as a stepping-stone for further research on innovations that combine fashion with technology.

• Structural Engineering and Mechanics
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• v.90 no.1
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• pp.97-106
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• 2024

This paper presents a significant contribution to aided design by conducting an analytical examination of geometric links with the aim of establishing criteria for assessing an analogy measure of the extrinsic geometric and kinematic characteristics of the Variable Compression Ratio (VCR) engine with a Geared Mechanism (GBCM) in comparison to the existing Fixed Compression Ratio (FCR) engine with a Standard-Reciprocating Crankshaft configuration. Employing a mechanical approach grounded in projective computational methods, a parametric study has been conducted to analyze the kinematic behavior and geometric transformations of the moving links. The findings indicate that in order to ensure equivalent extrinsic behavior and maintain consistent input-output performance between both engine types, precise adjustments of intrinsic geometric parameters are necessary. Specifically, for a VCR configuration compared to an FCR configuration, regardless of compression ratio and gearwheel radius, for the same crankshaft ratios and stroke lengths, it is imperative to halve lengths of connecting rods, and crank radius. These insights underscore the importance of meticulous parameter adjustment in achieving comparable performance across different engine configurations, offering valuable implications for design optimization.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.97-105
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• 2011

This paper presents how one can investigate the effects on crash occurrence of freeway geometric design elements including the horizontal, vertical alignment and road environment. At present, the available research results for the most part involve geometric data analysis that are obtained along a relatively long section of freeway, and, because of the long section's diverse geometric conditions, the results tend to miss the specific local geometric impacts on vehicle crashes. In this regard, this research attempts to establish vehicle crash models based on a set of freeway geometric patterns whose crash generating characteristics are identical because they are homogeneous in terms of producing the same vehicle operating speeds, and subsequently their actual relationships are described by providing statistical analysis made in this research. Also each standard is comprised of part of straight, curve and continuous curve. This research has revealed that each type of model has different relation between accident and geometry structure. This research results should be useful for doing more reasonable highway designs and safety audit analysis.

• Journal of the Korean Society of Costume
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• v.60 no.6
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• pp.11-22
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• 2010

Purpose: The purpose of this study is to develop golf wear textile design, produce simulation and samples, and create original designs using geometric patterns. Significance: If modern people's trend to pursue well-being is be associated with healthy and active lifestyle and the design which combines a sport sense into artistic image appears in golf wear, it is a very significant effort to settle the role of sport as a mega trend. Contents: This study examined the general concept of geometric patterns and the situation and characteristics of women's golf wear. Finally, the design and simulation of gold wear textile were proposed. Study Instruments: For theoretical research, articles, books, literatures, and Internet materials published at home and abroad were reviewed and collected. For empirical research, a dot, a stripe(a line), a square, and an oval were selected and simulation was tested visually after the development of textile designs. Finally it was directly produced and golf wear design was developed. Photoshop CS 3 and Wacom intuos 3 were used as a general-purpose program and hardware respectively. DTP printing was used for sample work. Based on research results, geometric patterns range broadly and diversely from prehistoric remains and relics to contemporary art, design, architecture, and fashion. It is a unique formative element with value and attraction as the infinite object of inquiry beyond an area and the times. The combination of geometric patterns with art touch could complement the rigidity of design. It contributed to the perception of important role of art in the design area, namely, the importance of design containing artistry.

• Journal of Korean Society of Steel Construction
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• v.23 no.1
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• pp.13-27
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• 2011

This paper presents an investigation of the structural stability of cable-stayed bridges, using geometric nonlinear finite-element analysis and considering various geometric nonlinearities, such as the sag effect of the cables, the beam-column effect of the girder and mast, and the large displacement effect. In this analytic research, a nonlinear frame element and a nonlinear equivalent truss element were used to model the girder, mast, and cable member. The live-load cases that were considered in this research were assumed based on the traffic loads. To perform reasonable analytic research, initial shape analyses in the dead-load case were performed before live-load analysis. In this study, the geometric nonlinear responses of the cable-stayed bridges with different cable arrangement types were compared. After that, parametric studies on the characteristics of the structural stability in critical live-load cases were performed considering various geometric parameters, such as the cable arrangement type, the stiffness ratios of the girder and mast, the area of the cables, and the number of cables. Through this parametric study, the effect of geometric shapes on the structural stability of cable-stayed bridges was investigated.

• Journal of Educational Research in Mathematics
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• v.19 no.1
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• pp.143-161
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• 2009

This study was designed to gain insights into students' visualization process in geometric problem solving. The visualization model for analysing visual process for geometric problem solving was developed on the base of Duval's study. The subjects of this research are two Grade 9 students and six Grade 10 students. They were given 2D-geometric problems. Their written solutions were analyzed problem is research depicted characteristics of process of visualization of individually. The findings on the students' geometric problem solving process are as follows: In geometric problem solving, visualization provided a significant insight by improving the students' figural apprehension. In particular, the discoursive apprehension and the operative apprehension contributed to recognize relation between the constituent of figures and grasp structure of figure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.327-336
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• 2012

This study presents the effects of various geometric properties on the ultimate behavior of steel cable-stayed bridges. In general, cable-stayed bridges are well known as a very efficient structural system, because of those geometric characteristics, but at the same time, the structure also shows complex structural behavior including various nonlinearities which significantly affect to the ultimate behavior of the structure. In this study, the effects of various geometric properties of main members on the ultimate behavior under specific live load cases, which had been studied in previous studies, were investigated using a rational analytical method. In this parametric study, sectional dimensions of main members were considered as main geometric parameters. For the rational ultimate analysis under specific live load cases, the 2-step analysis method, which contains initial shape analysis and live load analysis, was used. As the analysis model, 920.0 m long steel cable-stayed bridges were used and two different types of cable arrangement were considered to study the effect of the cable arrangement types. Through this study, the effects of various geometric properties on the characteristics of the ultimate behavior of steel cable-stayed bridges were intensively investigated.