• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.12
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• pp.793-799
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• 2016

In a hybrid fuel cell system, low-temperature reforming technology, which uses waste heat as a heat source, is applied to improve system efficiency. A low temperature reformer is required to optimize geometry in low thermal conditions so that the reformer can achieve the proper methane conversion rate. This study analyzed internal temperature distributions and the reaction patterns of a reformer by considering the change of the shape factor on the limited heat supply condition. Unlike the case of a high temperature reformer, analysis showed that the reaction of a low temperature reformer takes place primarily in the high temperature region of the reactor exit. In addition, it was confirmed that the efficiency can be improved by reducing the GHSV (gas hourly space velocity) or increasing the heat transfer area in the radial direction. Through reacting characteristic analysis, according to change of the aspect ratio, it was confirmed that a low temperature reformer can improve the efficiency by increasing the heat transfer in the radial direction, rather than in the longitudinal direction.

• Journal of Fashion Business
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• v.10 no.1
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• pp.79-93
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• 2006

The purpose of this study is to analyze designs of exhibition clothing in terms of the use of Korean image, to review objectively contents about the use of traditional image, understand external elements of works, and give directions and basic data for future works. This study selected the total 250 works as the subject of this study among the collected data. This study classified and examined the use of Korean image found in exhibition clothing according to period, item, line and form, material, technique of expression and accessary between 1996 and 2004. The results of analysis are as follows (1) The most artworks were comprised in adaptation were Choson costume. (2) Most of them were clothing works for female. The item of chima were the most preferred in use. (3) The straight lines are used more frequently than curved lines. Forms of skirts were applied to those of silhouettes, H and A form were common. (4) In terms of materials, traditional materials such as silk, linen and cotton were commonly used. (5) Geometric patterns and plant pattern were found more often than others. (6) In terms of techniques of expression, patchwork was most frequent, quilting, embroidery and pleating were ranked second, third and fourth. (7) In accessaries and other item, gorom were most common and norigae were ranked second. (8) As Korean image has been expressed by fine parts of traditional costumes, the traditional living item, and local symbols, the range of works are becoming wider.

• Journal of Fashion Business
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• v.11 no.4
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• pp.52-68
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• 2007

[ $Courr{\grave{e}}ges$ ]Look style has been showing up continuously since 1980s in the fashion world. In response to that, this study aimed to look into the trend of design in 1960s and examine the formative artistic characteristics in $Courr{\grave{e}}ges$ Look in order to explore the $Courr{\grave{e}}ges$ Look of Andre Courregs. Following the flow of the times, the $Courr{\grave{e}}ges$'s design has transformed and developed through the styles of the pants suit look, the space age look, the mini look and the sporty look. His own style constructed by simple line like a mini skirts, accurate rates, geometric patterns, high tech materials, vivid color and etc, in 1960s. He has also innovated the fields of textile, garment cutting, details, and accessories. The $Courr{\grave{e}}ges$ Style was expressed by pure&avant-garde style, sporty&modern style, cheerful&reveal style and dynamic&funny style. Functionality with humor to $Courr{\grave{e}}ges$ was an important element that expresses both youth and casual. For the active, new woman, not only a funtional beauty but also a futuristic sensibility is expressed in the $Courr{\grave{e}}ges$ Style.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.1
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• pp.25-34
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• 2010

Design in the 21st Century requires showing extraordinary and revolutionary possibilities by merging multiple cultures or different art forms. 21C fashion also increases its's complexity through the blending in of other design field's styles and forms. In other words, 21C's fashion design involves not only clothing, but combines techniques, aspects and functions fulled from various design categories. As a result, Current fashion design becomes more unique, and shows various styles. From this point of view, this study focuses on creating and suggesting unique textile designs through the understanding of design processes of textiles, which are inspired by high tech architectural structures. The fundamental shape of the architectural structures were simplified into thick lines and geometric shapes. these design elements were then transferred into textile designs. As a result, unique textile looks were created, and were applied to the apparel designs by CAD to see 3d simulations. Exchanging or merging ideas of different design categories leads innovative and fresh looks. 21C is rapidly changing, and designers need to continually introduce new looks every season. Incorporating 21st Century consumption patterns, designers must understand the process of creating original designs through various methods. The innovative fabric designs for this study involved a creative process of drawing from a step by step breakdown of two separate design fields, which were then merged into one finished design. The data and research from this study can be used as a reference tool for any further applicable fashion and textile designs in the future.

• Journal of the Korean Society of Costume
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• v.56 no.1 s.100
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• pp.81-96
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• 2006

Fashion is very superficial. However, it is expressed through the culture that is a cause of internal change and therefore its contents are defined by the cultural features. In this study, to study the aesthetic properties of the French fashion, the internal fashion contents are defined according to the cultural characteristics of France and based on the definition, the external features are investigated. The cultural characteristic was analyzed based on the reference literatures on the French culture. Based on the cultural characteristics of France, the aesthetical properties of the contemporary French fashion can be analyzed as follows: ${\cdot}$Dualism is the internal contents of the French culture with multiple sources, and it implies that opposing values such as female and male, traditionalism and modernism, simplicity and decoration are coexisting. Simplicity is pursued but decorative elements are in harmony and new phase of time is reflected while certain style has lasted for a long period of time to become a tradition. Furthermore, a rational trend combining masculinity and femininity, simultaneously exist with a trend that emphasizes feminine image. ${\cdot}$Multiculturism is a mysterious feature that has adapted the oriental or other cultural factors into the forms, patterns, colors and material of costumes. It has also been reconstructed with the French and the modern tastes. ${\cdot}$Avant-gardism is pursuing a novel aesthetic value against the former value system. It recognizes the human body as an object of figurative arts therefore emphasizes the body with geometric shapes to deny the fixed-idea, or engraft new materials and technologies to express the futuristic aspects.

• Composites Research
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• v.16 no.4
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• pp.29-35
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• 2003

In this paper. various tow parameters such as equivalent tow thickness, amplitude of longitudinal tow and tow intervals were investigated and compared with each other by using microscopic observation to find out the exact deformation patterns between both directions of the fabric structure(Longitudinal and Transverse Directions). And those observation results were compared with bias extension. biaxial tests results with dry fabric which has the same tow structure as the draped helmet materials and also compared with prepreg specimen which is cured by autoclave moulding without vacuum and pressure condition. Specimens for the observation were taken from draped helmet which is made of fabric composite(Five Harness Satin Weave). From the observation results, it was found that there are different deformation pattern between tow directions and effect of geometric condition on the deformation of the fabric materials during draping process was verified.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.7
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• pp.2097-2107
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• 1996

The dynamic photoelastic technique had been utilized to investigate the possibillity of relieving the large local singular stresses induced at the corner of a right- angle- indenter. The indenter compressed a semi-infinite body dynamically with an impact load applied on the top of the indenter. The effects of the geometric changes of the indenter in terms of the diameter (d) and the location (1) of the stress relieving notch on the behavior of the dynamic contact stresses were investigated. The influence of stress relieving notches positioned along the edge of the semi-infinite body on the dynamic contact stresses were also studied by changing the diameter (D) and the location (L) of the notch. A multi-speak-high speed camera with twelve sparks were used to take photographs of full field dynamic isochromatic fringe patterns. The contact singular stresses were found to be released significantly by the stress relief notches both along the indenter and the edge of the semi-infinite body. The optimal position and geometry of the stress relieving notches were obtained with the aid of limited experimental results.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.1
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• pp.13-23
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• 2003

Backgrounds: The present study in angulated coronary stenosis was to evaluate the influence of velocity and wall shear stress (WSS) on coronary atherosclerosis, the changes of hemodynamic indices following coronary stenting, as well as their effect of evolving in-stent restenosis using human in vivo hemodynamic parameters and computed simulation quantitatively and qualitatively. Methods: Initial and follow-up coronary angiographies in the patients with angulated coronary stenosis were performed (n=80). Optimal coronary stenting in angulated coronary stenosis had two models: < 50 % angle changed(model 1, n=43), > 50% angle changed group (model 2, n=37) according to percent change of vascular angle between pre- and post-intracoronary stenting. Flow-velocity wave obtained from in vivo intracoronary Doppler study data was used for in vitro numerical simulation. Spatial and temporal patterns of velocity vector and recirculation area were drawn throughout the selected segment of coronary models. WSS of pre/post-intracoronary stenting were calculated from three-dimensional computer simulation. Results: Follow-up coronary angiogram demonstrated significant difference in the percent of diameter stenosis between two groups (group 1: $40.3{\pm}30.2$ vs. group 2: $25.5{\pm}22.5%$, p<0.05). Negative WSS area on 3D simulation, which is consistent with re-circulation area of velocity vector, was noted on the inner wall of post-stenotic area before stenting. The negative WSS was disappeared after stenting. High spatial and temporal WSS before stenting fell into within physiologic WSS after stenting. This finding was prominent in Model 2 (p<0.01) Conclusions: The present study suggests that hemodynamic forces exerted by pulsatile coronary circulation termed as WSS might affect on the evolution of atherosclerosis within the angulated vascular curvature. Moreover, geometric change, such as angular difference between pre / post-intracoronary stenting might give proper information of optimal hemodynamic charateristics for vascular repair after stenting.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.6 s.154
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• pp.948-960
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• 2006

Chogakpos are highly artistic works created by Korean women as a part of the Kyubang culture in the Chosun Dynasty from the late 19th century to the early 20th. Tessellation is a plaid pattern composed of squares that covers a surface or a space with figures completely without any gap or overlap. The present study purposed to make a comparative analysis of the formative pattern of Chogakp and tessellation in order to show the superiority of Korean Kyubang(the women's quarters called Kyubang in the Chosun Dynasty) culture. As for the research method, we analyzed relevant materials to examine the geometric characteristics and formative principles of tessellation. In addition, we analyzed the formative pattern of Chogakpo using Photographs. The scope of this study was limited to 148 old Chogakpos contained in Huh Dong-hwa's 'Yetpojagi'. According to the results of this research, similarities between Chogakpo and tessellation were as follows. First, in a regular polygon, the face was divided into regular triangles, squares and two or more regular polygons. Second, in a polygon, the face was divided into triangles and quadrangles. Third, the symmetry of tessellation was applied to Cintamani pattern Pojagi. Differences between Chogakpo and tessellation were as follows. First, different from Chogakpo, tessellation had various formative patterns utilizing different regular polygons including hexagons. Second, there was no overlapping repetition in tessellation. Third, there was no free pattern in tessellation.

• School Mathematics
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• v.15 no.2
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• pp.481-501
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• 2013

The purpose of this study is to review the role of dragging in dynamic geometry environments. Dragging is a kind of dynamic representations that dynamically change geometric figures and enable to search invariances of figures and relationships among them. In this study dragging in dynamic geometry environments is divided by three perspectives: dynamic representations, instrumented actions, and affordance. Following this review, six conclusions are suggested for future research and for teaching and learning geometry in school geometry as well: students' epistemological change of basic geometry concepts by dragging, the possibilities to converting paper-and-pencil geometry into experimental mathematics, the role of dragging between conjecturing and proving, geometry learning process according to the instrumental genesis perspective, patterns of communication or discourse generated by dragging, and the role of measuring function as an affordance of DGS.