• Title/Summary/Keyword: 3D (3Dimensional)

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Analysis of Three-dimensional Nonaxisymmetric Spin-up by Using Parallel Computation (병렬계산에 의한 비축대칭 3차원 스핀업 유동해석)

  • Park, Jae-Hyoun;Choi, Yoon-Hwan;Suh, Yong-Kweon
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.512-517
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    • 2001
  • In this study, spin-up flows in a rectangular container are analysed by using three-dimensional computation. In the numerical computation, we use the parallel computer system of PC-cluster type. We compared our results with those obtained by two-dimensional computation. Effect of velocity and vorticity on the flow is studied. The result shows that two-dimensional solution is in good agreement with the 3-D result. Attention is given to the region where the 3-D flow is significant.

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Comparison of the observer reliability of cranial anatomic landmarks based on cephalometric radiograph and three-dimensional computed tomography scans (삼차원 전산화단층촬영사진과 측모두부 방사선규격사진의 계측자에 따른 계측오차에 대한 비교분석)

  • Kim, Jae-Young;Lee, Dong-Keun;Lee, Sang-Han
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.36 no.4
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    • pp.262-269
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    • 2010
  • Introduction: Accurate diagnosis and treatment planning are very important for orthognathic surgery. A small error in diagnosis can cause postoperative functional and esthetic problems. Pre-existing 2-dimensional (D) chephalogram analysis has a high likelihood of error due to its intrinsic and extrinsic problems. A cephalogram can also be inaccurate due to the limited anatomic points, superimposition of the image, and the considerable time and effort required. Recently, an improvement in technology and popularization of computed tomography (CT) provides patients with 3-D computer based cephalometric analysis, which complements traditional analysis in many ways. However, the results are affected by the experience and the subject of the investigator. Materials and Methods: The effects of the sources human error in 2-D cephalogram analysis and 3-D computerized tomography cephalometric analysis were compared using Simplant CMF program. From 2008 Jan to 2009 June, patients who had undergone CT, cephalo AP, lat were investigated. Results: 1. In the 3 D and 2 D images, 10 out of 93 variables (10.4%) and 11 out 44 variables (25%), respectively, showed a significant difference. 2. Landmarks that showed a significant difference in the 2 D image were the points frequently superimposed anatomically. 3. Go Po Orb landmarks, which showed a significant difference in the 3 D images, were found to be the artificial points for analysis in the 2 D image, and in the current definition, these points cannot be used for reproducibility in the 3 D image. Conclusion: Generally, 3-D CT images provide more precise identification of the traditional cephalometric landmark. Greater variability of certain landmarks in the mediolateral direction is probably related to the inadequate definition of the landmarks in the third dimension.

Three-dimensional/two-dimensional convertible integral imaging display system using an active mask (동적 마스크를 이용한 3D/2D 변환 집적영상 디스플레이 시스템)

  • Oh, Yongseok;Shin, Donghak;Lee, Byung-Gook;Jeong, Shin-Il
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.12
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    • pp.3055-3062
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    • 2014
  • 3D integral imaging technique with an active mask is capable of displaying real 3D images with high resolution in space. In this paper, we present a novel 3D/2D convertible integral imaging display system using an active mask. For the proposed method, the principles of 3D, 2D, and 3D/2D composed operations are explained according to the displayed images through two LCD panels. In 3D mode, the elemental images and the mask images are displayed in two display panels. On the other hand, the light source image and 2D image are displayed in 2D mode. In addition, 3D/2D mode is obtained using the spatial separation for 3D and 2D modes. To show the feasibility of the proposed method, we carry out the preliminary experiments and present the optical results.

The Database Development of 2-D and 3-D Hands Measurement for Improving Fitness of Gloves - Focused on the Classification of Hand Type and Analysis of 3-D Hand Shape - (장갑의 적합성 향상을 위한 손부의 2차원 및 3차원 계측정보 DB구축에 관한 연구 -손의 유형분석 및 3차원 입체형상 분석을 중심으로-)

  • 최혜선;김은경
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.910
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    • pp.1300-1311
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    • 2004
  • The aim of this study was to provide the 2 and 3 dimensional statistics requisite in the sizing system and design of gloves. The 64 2-dimensional static measurements were selected to provide information about hands. Participants in the study were 824 adults, aged between 18 and 64. To summarize the information from the measurement values, a Factor Analysis and a Cluster Analysis among multivariate analyses were performed. 3-D scanner was used for visual results of hand shape of each cluster. The results were as follows. Twenty-two items were used for the factor and cluster analysis in order to classify the adult hand shape. The variable quantities that are explained by a total of 3 factors amounted to under 79.37% of the variable quantities. The definition results of the factors related to the hands are as follows: Factor 1 is the horizontal dimension, the thickness of hand factor; Factor 2 is the height of the crotch; and Factor 3 is the vertical dimension of the hand. The adults' group hand was divided into 2 clusters according to a cluster analysis using factor scores. The characteristics according to hand type were as follows: Cluster 1 referred to high horizontal dimensions and thickness, rather small vertical dimensions and crotch height; and Cluster 2 represented the rather smaller horizontal dimensions and thickness but longer hand length than Type 1. To provide specific shape data of each cluster, 3-D scanner measurement was performed. 3-dimensional data base was developed for each cluster type and visual information was provided.

Realistic 3-dimensional using computer graphics Expression of Human illustrations (컴퓨터그래픽스를 이용한 사실적인 3D 인물 일러스트레이션의 표현)

  • Kim, Hoon
    • Archives of design research
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    • v.19 no.1 s.63
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    • pp.79-88
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    • 2006
  • A human face figure is a visual symbol of identity. Each different face per person is a critical information differentiating each person from others and it directly relates to individual identity. When we look back human history, historical change of recognition for a face led to the change of expression and communication media and it in turn caused many changes in expressing a face. However, there has not been no time period when people pay attention to a face more than this time. Technically, the advent of computer graphics opened new turning point in expressing human face figure. Especially, a visual image which can be produced, saved, and transferred in digital has no limitation in time and space, and its importance in communication is getting higher and higher. Among those visual image information, a face image in digital is getting more applications. Therefore, 3d (3-dimensional) expression of a face using computer graphics can be easily produced without any professional techniques, just like assembling puzzle parts composed of the shape of each part ands texture map, etc. This study presents a method with which a general visual designer can effectively express 3d type face by studying each producing step of 3d face expression and by visualizing case study based on the above-mentioned study result.

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A Study on the Modeling of Three-Dimensional Work Structure Using Web 3D in Cyberspace (Cyberspace에서 Web 3D를 이용한 3차원 공사 구조물 모델링의 활용성 제언)

  • Lee Hui-Chul;Lee Tai-Sik;Kim Young-Hyun
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.531-534
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    • 2002
  • Complexity in construction projects has increased over the years, which has led to an increase in the number of organizations involved in those projects. In today's environment, these organizations operate in different parts of the world requiring their personnel to be geographically distributed. So, these organizations construct and utilize the information systems. However, looking into this systems' content, those use two-dimensional planes such as pictures and drawings to check the scheduling etc., which cause the defect of communication and problems such as change order. Accordingly, this study introduces the Web 3Ds and 3D Libraries, intends to present the effect on modeling of three-dimensional work structure using Web 3D in cyberspace.

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Design of Brassiere Pattern for Big Size Breast Women -Based on 3D Breast Scanning Data- (유방이 큰 여성을 위한 브래지어 패턴 설계 -3차원 유방 형상 자료를 중심으로-)

  • Han, Chohee;Yi, Kyong-Hwa
    • Journal of the Korean Society of Clothing and Textiles
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    • v.43 no.2
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    • pp.204-214
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    • 2019
  • A CAD program has recently been introduced that can be directly developed into a three-dimensional human body shape and made into a pattern. It is possible to fabricate a bra that reflects the volume and surface area of the breast; however, it still needs to be verified. This study investigates the average size and shape of 20 big-breasted women and designs a brassiere pattern for women with large breasts using a 3D Flattening function of OptiTex PDS v15.6. In addition, the study verifies the reliability of the proposed method compared to a conventional brassiere pattern. The study results are as follows. First, the three dimensional measurement values were smaller than the direct measurement dimensions when the three dimension measurement dimensions of the subjects were compared with the direct measurement dimensions, the replica measurement dimensions and the three dimensional measurement dimensions. Second, the 3D flattening pattern reflects the actual shape, length, and area of the actual breast when comparing a brassiere pattern using a 3D shape and pattern reflecting the direct measurement.

A Study of the 3D-Reconstruction of indoor using Stereo Camera System (스테레오 카메라를 이용한 실내환경의 3차원 복원에 관한 연구)

  • Lee Dong-Hun;Um Dae-Youn;Kang Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.1
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    • pp.42-47
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    • 2005
  • In this papcr, we address the 3D reconstruction of the indoor circumstance using what the data is extracted by a pall of image from Stereo Camera. Generally sucaking, there arc three methods to extract 3-Dimensional data using IR sensor, Laser sensor and Stereo camera sensor. The best is stereo camera sensor which can show a high performance at a reasonable price. We used 'Window Correlation Matching Method' to extract 3-Dimensional data in stereo image. We proposed new Method to reduce error data, said 'Histogram Weighted Hough Transform'. Owing to this mettled, we reduced error data in each stereo image. So reconstruction is well done. 3-Dimensional Reconstruction is accomplished by using the DirectX that is well known as 3D-Game development tool. We show that the stereo camera can be not only used to extract 3-dimensional data but also applied to reconstruct the 3-Dimensional circumstance. And we try to reduce the error data using various method.

Preparation of Three-Dimensional Graphene/Metal Oxide Nanocomposites for Application of Supercapacitors (슈퍼커패시터 응용을 위한 3차원 그래핀/금속 산화물 나노복합체 제조)

  • Kim, Jung Won;Choi, Bong Gill
    • Applied Chemistry for Engineering
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    • v.26 no.5
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    • pp.521-525
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    • 2015
  • Graphene-based electrode materials have been widely explored for supercapacitor applications due to their unique two-dimensional structure and properties. In particular, Three-dimensional (3D) graphene materials are of great importance for preparing electrode materials because they can provide large surface area, efficient and rapid electron and ion transfer, and mechanical stability. Recently, a number of 3D hybrid architecture of graphene/metal oxides have been developed to increase simultaneously energy and power densities of supercapacitors. This review presents the recent progress of 3D nanocomposites based on graphene and metal oxides. Preparation methods and structures of these 3D nanocomposites and their great potential in supercapacitor applications have been summarized.

A Study on the Generation of 3 Dimensional Graphic Files Using SPOT Imagery (SPOT 위성영상을 이용한 3차원 그래픽 화일 생성연구)

  • Cho, Bong-Whan;Lee, Yong-Woong;Park, Wan-Yong
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.1 s.5
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    • pp.79-89
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    • 1995
  • Using SPOT satellite imagery, 3 dimensional geographic information can be obtained from SPOT's oblique viewing image. Especially, SPOT provides high spatial resolution, adequate base/height ratio and stable orbit characteristics. In this paper, 3D terrain features were extracted using SPOT stereo image and also the techniques for generation of 3D graphic data were developed for the extracted terrain features. We developed computer programs to generate automatically 3D graphic files and to display geographic information on the computer screen, The results of this study may be effectively utilized for the development of 3D geographic information using satellite images.

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