• Title/Summary/Keyword: Shape Simplification

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Assessment of Grid Sensitivity in the FDS Field Model to Simulate the Flame Propagation of an Electric Cable Fire (케이블 화재의 화염전파 해석을 위한 FDS 모델의 격자민감도 평가)

  • Kim, Sung-Chan;Lee, Seong-Hyuk
    • Journal of the Korean Society of Safety
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    • v.23 no.4
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    • pp.30-35
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    • 2008
  • The present study has been conducted to examine the effect of grid resolution on the predicted results for electric cable fire using pyrolysis model in FDS(Fire Dynamics Simulator, version 5). The grid independent test for different grid resolutions has been performed for a PE coating cable and the grid resolution is defined by the non-dimensional characteristic length of fire and mean grid size. The calculated maximum heat release rate and mean flame spread rate were almost constant for higher grid resolution of 20${\sim}$25 and the computing time for the grid resolution takes approximately 20hours to solve flame propagation with pyrolysis model. The geometrical simplification of a electric cable dose not greatly affect on the maximum heat release rate and flame spread rate and the rectangular approximation of cable shape gives acceptable result comparing with the round cable with stepwise grid.

Complete 3D Surface Reconstruction from an Unstructured Point Cloud of Arbitrary Shape by Using a Bounding Voxel Model (경계 복셀 모델을 이용한 임의 형상의 비조직화된 점군으로부터의 3 차원 완전 형상 복원)

  • Li Rixie;Kim Seok-Il
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.8 s.251
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    • pp.906-915
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    • 2006
  • This study concerns an advanced 3D surface reconstruction method that the vertices of surface model can be completely matched to the unstructured point cloud measured from arbitrary complex shapes. The concept of bounding voxel model is introduced to generate the mesh model well-representing the geometrical and topological characteristics of point cloud. In the reconstruction processes, the application of various methodologies such as shrink-wrapping, mesh simplification, local subdivision surface fitting, insertion of is isolated points, mesh optimization and so on, are required. Especially, the effectiveness, rapidity and reliability of the proposed surface reconstruction method are demonstrated by the simulation results for the geometrically and topologically complex shapes like dragon and human mouth.

The Effectiveness due to fixed position change of fault protective wire on catenary system (전차선로에서 보호선 설치 위치변경에 따른 효과 검토)

  • Ryoo, Hyang-Bok;Ahn, Young-Hoon;Hyun, Chung-Il;Kang, Seung-Wook
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1456-1459
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    • 2007
  • Protective equipments have a very important protection role in power accident on catenary line. These equipments are installed on electrical pole. The poles have complicated with many bands(moveable bracket, branch wire anchor, shield wire, etc). So we have improved bands and installed bands on pole to test technical condition. The Result has showed effectiveness due to fixed position change of fault protective wire and to improve band shape. For example, reduction of band made cost, simplification of installing, correct position of protective wire and shield wire.

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Edge Watermarking of 3-Dimensional Shape Recognition System (3차원 형상 인식 시스템에서의 에지 워터마킹)

  • 윤재식;유상욱;성택영;김희정;권성근;이응주;권기룡
    • Proceedings of the Korea Multimedia Society Conference
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    • 2004.05a
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    • pp.163-166
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    • 2004
  • 본 논문은 3차원 형상 인식시스템으로부터 스캔 한 3차일 영상 데이터의 깊이정보에 3차원 에지를 추출하여 워터마크를 삽입하는 알고리즘을 제안한다. 제안한 알고리즘에서는 3차원 수직 평형 형상 인식기로 object scanning을 한 데이터 값들을 추출한다. 이 추출된 값들의 특성은 2차원 영상 즉 x, y축에 각각의 픽셀에 깊이정보를 가지는 3차원영상으로서 기존의 3차원영상과는 다른 차이를 가지며 영상의 품질이 우수하며 많은vertex 정보와 메쉬 정보를 가지고 있다. 따라서 획득된 데이터에서 x좌표와 y좌표는 영상에 있어서 위치를 나타내는 정보이고, T좌표는 3차원영상을 형성하는 깊이 정보들이다. 3차원 형상 인식시스템에서 스캔 한 3차원 얼굴영상으로부터 에지를 검출하여 에지가 존재하는 위치에 워터마크를 삽입하는 알고리즘을 제안하였다. 본 논문에서 제안한 워터마킹 알고리즘의 성능 평가를 위한 모의실험 한 결과 워터마크가 삽입된 모텔의 절단(cropping), 리메쉬(remesh) 및 메쉬간소화(mesh simplification) 공격에 대한 견고성이 우수함을 확인함으로써 3차원형상 인식 시스템에 직접적인 워터마크 삽입이 가능함을 증명하였다.

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A Study on the Formative Elements of Neo-plasticism Applied on Contemporary Fashion (현대패션에 응용된 신조형주의의 조형요소에 관한 연구 - 몬드리안 회화를 중심으로 -)

  • Jeong, Kyung-Hee;Bae, Soo-Jeong
    • Korean Journal of Human Ecology
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    • v.9 no.1
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    • pp.51-61
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    • 2006
  • The purpose of this study is to examine the relation between the trend of art and fashion which predominate a certain time. In order to achieve this goal, this study intends to analyze how plasticity found in Mondrian's pictures are applied to modern fashion with its focus on formative elements. Mondrian was ahead of abstractionism, a major trend of contemporary art, and defined the theory of neo-plasticism. The theory of neo-plasticism defined by Mondrian is characterized by the limited expression of lines and shapes by using only vertical and horizontal straight lines, and right angles and four-sided figures weaved by the lines, and the use of achromatic color(black, white, and gray) in three primary colors(red, blue, and yellow). Based on his theory, he fully displayed the world of geometric abstraction. Mondrian's formative elements which have been applied in modern fashion can be divided into shape and color, For the element of shape, first, horizontal and vertical lines have been applied to patterns, trimmings, detail, and plane of textiles through simplification of design, representing proportion, balance, and stress in a silhouette, Second, plane and diamond shapes made of horizontal and vertical lines have been applied to textiles or patterns with uniqueness. For the element of color, first, three primary colors and achromatic colors are used to seek the aesthetics of balance and harmony that are produced in the strain of conflict through brightness, chroma, and complementary colors, Second, primary colors of high chroma and brightness which are much stronger than pictures are used to express a modern sense. Formative elements of neo-plasticism, which have been applied to modern fashion suggested by this study, are connected with the trend of art contemporary designers have borrowed, Accordingly, this study will become a very helpful material which provides designers with original ideas in developing materials and patterns which connect design with art.

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A Study on the Abstraction of the Human Body in Contemporary Dance Costumes - Focusing on Oscar Schlemer's Costume Theory - (현대 무용의상에 나타난 인체의 추상화에 관한 연구 - 오스카 슐레머의 의상이론을 중심으로 -)

  • Han, Kyeng-Ha;Geum, Key-Sook
    • Journal of the Korean Society of Costume
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    • v.60 no.10
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    • pp.133-145
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    • 2010
  • The study used four basic formats classified based on the four principles on costumes discussed in the paper 'Human Beings and Arts Phenomena' by Oskar Schlemmer who studied the relationships between stage space and the human body as an analysis tool with regard to analyses on the abstraction of human body in contemporary dance costume. Abstraction of human body expressed in costume for contemporary dance is as follows: Expansions caused by unclear boundary between spaces and costumes, and the principles of three-dimensional abstract spaces based on a geometric cube change heads, trunks, arms and legs to achieve expansions. Similar mechanical shape is a type of shape made in a succession of functional principles of human body in relationships with spaces. As mechanical mechanism is added to the geometric transformation of a specific part of human body, mechanicalness is contained in it. Motion organisms are geometric simplification of moving traces in a space based on conversion into mechanical organisms based on principles of motion, and as mechanical rotation, consecutive speed caused by refraction and directionality are suggested, mobility is achieved. Immaterial shape is based on change into a metaphysical form, and it is converted into animals, plants or a third life that symbolize body parts. It has metaphysical significance in each body part and extends sensibility. As a result of the study, development into abstract succession and a techno art mode has been confirmed. Combination of geometric cubic figures with the organic human body and configuration of the human body pursued by Oskar Schlemmer's geometric abstraction through the proactive accommodation of mechanical aesthetics has been succeeded and expressed in the contemporary dance costumes.

Morphological Hand-Gesture Recognition Algorithm (형태론적 손짓 인식 알고리즘)

  • Choi Jong-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.8
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    • pp.1725-1731
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    • 2004
  • The use of gestures provides an attractive alternate to cumbersome interface devices for human-computer interaction. This has motivated a very active research area concerned with computer vision-based analysis and interpretation of hand gestures. The most important issues in gesture recognition are the simplification of algorithm and the reduction of processing time. The mathematical morphology based on geometrical set theory is best used to perform the processing. A key idea of proposed algorithm in this paper is to apply morphological shape decomposition. The primitive elements extracted to a hand gesture include in very important information on the directivity of the hand gestures. Based on this characteristic, we proposed the morphological gesture recognition algorithm using feature vectors calculated to lines connecting the center points of a main-primitive element and sub-primitive elements. Through the experiment, we demonstrated the efficiency of proposed algorithm. Coupling natural interactions such as hand gesture with an appropriately designed interface is a valuable and powerful component in the building of TV switch navigating and video contents browsing system.

Analysis of Impact Behavior of Al-Alloy Castings Considering Internal Defects (내부 결함을 포함한 주조 알루미늄 합금의 충격 거동 해석)

  • Jo, Seong-Woo;Kwak, Si-Young
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.36 no.12
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    • pp.1599-1604
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    • 2012
  • In general, internal defects, such as shrinkage in casting, cause stress concentration and can be a starting point for cracks. Therefore, it is important to understand the effects of internal defects on the mechanical properties including the impact behavior. This study aim is to evaluate the effects of internal casting defects on the impact performance of Al-alloy castings. Both an experimental method and computational analysis were used to achieve the research objective. The internal defects in the casting were scanned using an industrial CT scanner, and their shape was simplified using ellipsoidal primitives for impact analysis. The good agreement between the experimental and computer simulation results verified the reliability of the proposed computational method for the FEA of casting components with internal defects.

Shape-Simplification Analysis Model for Fatigue Life Prediction of Casting Products Considering Internal Defects (내부 결함을 고려한 주조 제품의 피로수명 예측을 위한 결함 형상단순화 해석모델)

  • Kwak, Si-Young;Kim, Hak-Ku
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.10
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    • pp.1243-1248
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    • 2011
  • Internal defects are a major concern in the casting process because they have a significant influence on the strength and fatigue life of casting products. In general, they cause stress concentration and can be a starting point of cracks. Therefore, it is important to understand the effects of internal defects on mechanical properties such as fatigue life. In this study, fatigue experiments on tensile specimens with internal defects were performed. The internal defects in the casting product were scanned by an industrial CT scanner, and its shape was simplified by ellipsoidal primitives for the structural and fatigue analysis. The analysis results were compared with experimental results for casting products with internal defects. It was demonstrated that it is possible to consider internal defects of casting products in stress and fatigue analysis. The proposed method provides a tool for the prediction of the fatigue life of casting products and the investigation of the effects of internal defects on mechanical performance.

A Study on Changes of Practical Korean Costume (생활한복의 변천에 관한 연구)

  • Choi, Kyung-Soon;Kim, Sun-Ryung
    • Fashion & Textile Research Journal
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    • v.1 no.1
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    • pp.34-42
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    • 1999
  • The purpose of this study was to change practical korean costume in 20C. In the early 20C, inflow of western civilization started to change korean costume. Since then gradually changes to be simple in Korean costume. Results of this study can be summarized as follows: Traditional jacket (jeo-go-li) gradually began to be long to waist line. This jacket length was to be long and it sleeve is to be short in early 2OC. Traditional skirt (Chi-rna) length was short to the calf of the leg. Traditional wide skirt was gradually to be narrow and pleats shape look as if it in go-gu-Ryeo Dynasty. The width of pleats was about 3~5 cm, be one-sided, look as if it western style in today. But pleats skirt already existed on a women's of the upper classes in go-gu-Ryeo Dynasty. Women's long Coat (do-lu-ma-gi) length was short to under hip line in late 20c. In this way, the practical idea, the factor of design was because of western idea in civilization ages, early 20C. Since then gradually reformed to be simple in Korean costume. Assuming that the trend of simplification in Korean costume is related to the idea of practical. Therefore Korean costume of living or a reformed Korean costume to be design of practical, functional, convenient, economically. And it must have to traditional idea, it is only beauty of shape, pattern, line, fabric in Korean costume.

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