• Title/Summary/Keyword: three-dimensional structure

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Computational Analysis of the Three-Dimensional Flow Fields of Sirocco Fan

  • Hah, Jae-Hong;Moon, Young-J.;Park, Jin-Moo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.2
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    • pp.44-50
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    • 2001
  • The Sirocco fan performance and its three-dimensional flow characteristics are numerically prediction by STAR-CD. Turbulent flow computations are performed using approximately 500,000 mesh points, and the performance results of tow computational methods, transient and quasi-static flow analyses are compared with experimental data. In the present study, our attention is focused on the three-dimensional flow characteristics of the Sirocco fan blades and the secondary flow structure in the scroll. For a design optimization study, the scroll shape is titled by $10^\circ$ to modify the secondary flow structure, which yields some improvement of the fan performance.

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Development of a Post-Processor for Three-Dimensional Forging Analysis (3차원 단조해석용 후처리기 개발)

  • 정완진;최석우
    • Transactions of Materials Processing
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    • v.12 no.6
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    • pp.542-549
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    • 2003
  • Three-dimensional forging analysis becomes an inevitable tool to make design process more reliable and more producible. In this study, in order to make the investigation for three-dimensional forging analysis more conveniently and accurately, a new post processor was developed. For post-processing of multi-stage forging simulation, efficient data structure was proposed and applied by using STL. New file architecture was developed to handle successive and huge data efficiently, common in three-dimensional forging analysis. Since sectioning and flow tracing plays an important role in the investigation of analysis result, we developed an algorithm suitable for 4-node and 10-node tetrahedron. This flow tracing algorithm can trace and reverse-trace flow through remeshing. Developed program shows good performance and functionality. Especially, a big size problem can be handled easily due to proposed data structure and file architecture.

Stiffener Layout Optimization to Maximize Natural Frequencies of a Curved Three-Dimensional Shell Structure (구부러진 3차원 박판 구조물의 고유 진동수 극대화를 위한 보강재 배치 최적화)

  • Lee, Joon-Ho;Park, Youn-Sik;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.954-957
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    • 2004
  • Based on the authors' previous work, where a geometric constraint handling technique for stiffener layout optimization problem using geometry algorithms was proposed, stiffener layout optimization to maximize natural frequencies of a curved three-dimensional shell structure was performed with a projection method. The original geometry of the shell structure was first projected on a two-dimensional plane, and then the whole optimization process was performed with the projected geometry of the shell except that the original shell structure was used for the eigenproblem solving. The projection method can be applied to baseline structures with a one-to-one correspondence between original and projected geometries such as automobile hoods and roofs.

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Synthesis of Melandrin Derivatives (Melandrin 유도체의 합성)

  • Lim, Jung-Ki;Woo, Won-Sick;Lee, Kang-Ro;Ma, Eun-Sook
    • YAKHAK HOEJI
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    • v.38 no.3
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    • pp.281-285
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    • 1994
  • Melandrin was isolated from the Melandrium firmum(Caryophyllaceae), its structure was N-(p-hydroxybenzoyl)-5-hydroxyanthranilic acid. Fourteen melandrin derivatives(I-XIV) were synthesized and according to MME calculation by the computer, optimized three dimensional structure of compounds was obtained. The space orientation of compounds was cis-form as a indomethacin.

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COMPARATIVE STUDY OF THREE-DIMENSIONAL RECONSTRUCTIVE IMAGES OF FACIAL BONE USING COMPUTED TOMOGRAPHY (전산화단층상을 이용한 안면골의 3차원재구성상의 비교 연구)

  • Song Nam-Kyu;Koh Kwang-Joon
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.22 no.2
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    • pp.283-290
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    • 1992
  • The purpose of this study was to evaluate the spatial relationship of facial bone more accurately. For this study, the three-dimensional images of dry skull were reconstructed using computer image analysis system and three-dimensional reconstructive program involved CT. The obtained results were as follows: 1. Three-dimensional reconstructive CT results in images that have better resolution and more contrast 2. It showed good marginal images of anatomical structure on both three-dimensional CT and computer image analysis system, but the roof of orbit, the lacrimal bone and the squamous portion of temporal bone were hardly detectable. 3. The partial loss of image data were observed during the regeneration of saved image data on three-dimensional CT. 4. It saved the more time for reconstruction of three-dimensional images using computer image analysis system. But, the capacity of hardware was limited for inputting of image data and three-dimensional reconstructive process. 5. We could observe the spatial relationship between the region of interest and the surrounding structures by three-dimensional reconstructive images without invasive method.

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Development of finite element numerical simulation for three-dimensional oxidation (3차원 산화 공정을 위한 유한요소법 수치 해석기 개발에 관한 연구)

  • 이제희;윤상호;송재복;김윤태;원태영
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.3
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    • pp.74-86
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    • 1997
  • With continued miniaturization and development of new devices, the highly nonuniform oxidation of three-dimensional non-planar silicon structures plays an increasingly important role. In this paper, the three-dimensional finite element numerical simulator. Grwoth of oxide is a coupled process of diffusion of oxidant and deformation of oxide. Because boundaries of oxide are moved in each time step and LOCOS structure is formed three-dimensional shape of sruface, it is necessary to develope an efficient node control algorithm that can locally generate and eliminate the node. Therefore we have developed the optimized three-dimensional mesh generator which is cpable of refining and eliminating the meshes at the moving boundary of oxide, and hve developed three-dimensional finite element oxidation solver.

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Time Historical Response Analysis of Three Dimensional Rectilinear Structure using the TSCM (전달강성계수법을 이용한 3차원 직선형 구조물의 시간이력응답 해석)

  • 문덕홍;강현석;최명수
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.1
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    • pp.108-115
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    • 2002
  • This paper suggests a new analysis algorithm for the time historical response of three dimensional rectilinear structure which is frequently found in a pipe line system of plant by the combination of the transfer stiffness coefficient method(TSCM) and the Newmark method. The present analysis algorithm for a time historical response can improve the computational accuracy and time remarkably owing to advantages of the TSCM in comparison with transfer matrix method(TMM). The structural system is modeled as a lumped mass system in this method. The analysis algorithm was formulated far the three dimensional rectilinear structure. We confirmed the validity of the present algorithm by comparing the numerical computation results of TSCM with those of TMM.

A Study on Dynamic Response Analysis Algorithm for Three Dimensional Structure (3차원 구조물의 동적응답 해석알고리즘에 관한 연구)

  • Moon, D.H.;Kang, H.S.;Choi, M.S.
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.637-642
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    • 2000
  • This paper suggests new analysis algorithm for tile dynamic response of three dimensional structure which is frequently found in pipe line system of plant by the combination of the transfer stiffness coefficient method(TSCM) and Newmark method. Presented analysis algorithm for dynamic response can improve the computational accuracy remarkably owing to advantages of tile TSCM in comparison of transfer matrix method(TMM). Analysis system was modeled as a lumped mass system in this mettled. The analysis algorithm for dynamic response was formulated for the three dimensional structure. The validity of the this method is demonstrated through the results of numerical experiment for simple computational model by the TSCM and TMM.

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A study on Calculating the Resistance characteristics analysis on Three-Dimensional Structure Using Computer Simulation Method. (컴퓨터 시뮬레이션을 이용한 3차원적 구조에서의 저항 특성 분석에 관한 연구)

  • Jang, U-Sun
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.683-686
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    • 2005
  • By now, we have been analysing the resistance values on 3 dimensional structure using experimental statical method or theoretical modeling, while devices miniaturizing reveals the limitation of the traditional methods to calculate 3 dimensional resistance. In addition, 2 dimensional analysing can not produce 3 dimensional characteristic following miniaturizing. To solve the limitations , we must do high level modeling of semi-conductor process. In this thesis, we analyzed the Laplace equation that is the basic and important for 3 dimensional structure resistance with computer simulation method and on the basis of this, analyzed the characteristic of resistance of 3 dimensional structure communication semiconductor device.

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A COMPARATIVE STUDY OF THREE-DIMENSIONAL RECONSTRUCTIVE IMAGES OF TEMPOROMANDIBULAR JOINT USING COMPUTED TOMOGRAM (전산화단층상을 이용한 측두하악관절의 삼차원 재구성상의 비교연구)

  • LIM SUK-YOUNG;KOH KWANG-JOON
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.23 no.2
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    • pp.335-344
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    • 1993
  • The purpose of this study was to clarify the spatial relationship of temporomandibular joint and to an aid in the diagnosis of temporomandibular disorder. For this study, three-dimensional images of normal temporomandibular joints were reconstructed by computer image analysis system and three-dimensional reconstructive program integrated in computed tomography. The obtained results were as follows: 1. Two-dimensional computed tomograms had the better resolution than three dimensional computed tomograms in the evaluation of bone structure and the disk of TMJ. 2. Direct sagittal computed tomograms and coronal computed tomograms had the better resolution in the evaluation of the disk of TMJ. 3. The positional relationship of the disk could be visualized, but the configuration of the disk could not be clearly visualized on three-dimensional reconstructive CT images. 4. Three-dimensional reconstructive CT images had the smoother margin than three-dimensional images reconstructed by computer image analysis system, but the images of the latter had the better perspective. 5. Three-dimensional reconstructive images had the better spatial relationship of the TMJ articulation, and the joint spaces were more clearly visualized on dissection images.

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