• Title/Summary/Keyword: Digitizing

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3D Model Retrieval Based on Orthogonal Projections

  • Wei, Liu;Yuanjun, He
    • International Journal of CAD/CAM
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    • v.6 no.1
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    • pp.117-123
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    • 2006
  • Recently with the development of 3D modeling and digitizing tools, more and more models have been created, which leads to the necessity of the technique of 3D mode retrieval system. In this paper we investigate a new method for 3D model retrieval based on orthogonal projections. We assume that 3D models are composed of trigonal meshes. Algorithms process first by a normalization step in which the 3D models are transformed into the canonical coordinates. Then each model is orthogonally projected onto six surfaces of the projected cube which contains it. A following step is feature extraction of the projected images which is done by Moment Invariants and Polar Radius Fourier Transform. The feature vector of each 3D model is composed of the features extracted from projected images with different weights. Our System validates that this means can distinguish 3D models effectively. Experiments show that our method performs quit well.

SEMI-AUTOMATIC EXTRACTION OF AGRICULTURAL LAND USE AND VEGETATION INFORMATION USING HIGH RESOLUTION SATELLITE IMAGES

  • Lee, Mi-Seon;Kim, Seong-Joon;Shin, Hyoung-Sub;Park, Jong-Hwa
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.147-150
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    • 2008
  • This study refers to develop a semi-automatic extraction of agricultural land use and vegetation information using high resolution satellite images. Data of IKONOS satellite image (May 25 of 2001) and QuickBird satellite image (May 1 of 2006) which resembles with the spatial resolution and spectral characteristics of KOMPSAT3. The precise agricultural land use classification was tried using ISODATA unsupervised classification technique and the result was compared with on-screen digitizing land use accompanying with field investigation. For the extraction of vegetation information, three crops of paddy, com and red pepper were selected and the spectral characteristics were collected during each growing period using ground spectroradiometer. The vegetation indices viz. RVI, NDVI, ARVI, and SAVI for the crops were evaluated. The evaluation process is under development using the ERDAS IMAGINE Spatial Modeler Tool.

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A Study on the Possibility of Pattern Design Using CAD System (With concentration on the change of coat basic pattern) (CAD System을 이용한 패턴디자인설계 활용가능성에 관한 연구(I)-Coat 원형을 중심으로-)

  • 김옥경
    • Journal of the Korean Society of Costume
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    • v.20
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    • pp.49-62
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    • 1993
  • The purpose of this research was to utilize of Pattern Design System(P.D.S) by using AM-300 The conclusion were like these : 1. A coat of basic pattern was selected by design sketch. 2. The basic pattern was input into computer by digitizing. 3. The basic pattern was change into designed shape by using various skills. This system were enabled to draw straight lines, curves, delete lines, sections of lines, extend lines, cut pattern into sections, measure line or section reproduce whole pattern shape of section, rotate and mirror pattern and complete patterns. 4. Automatic grading of finished master pattern have been developed by creation and modification of grading rules of basic pattern. 5. Production pattern added seam allowance, not-ches was generated by P.D.S menu option. 6. Finished pattern design was plotted out 100% and 20% size by AM-300 Plotter. This results will be the basic materials to develop the CAD SYSTEM if some problems were improve. Furthermore, the utilization of P.D.S is expected to be developing in pattern making process.

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A Study on the Data Input and Visualization of Sturctual Form on Topographic Relief in the Landscape Simulation Thchnique using CG (컴퓨터 그래픽스를 이용한 경관 시뮬레이션에 있어서 지형상에 구조물 형상 입력과 가시화 방법에 관한 연구)

  • 조동범
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.3
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    • pp.29-41
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    • 1996
  • The purposes of this study were to develope some techniques which can be used in the landscape simulation process using PC based computer grahics. As a result, a couple of utilities were programmed in AutoLISP language. The one(DSLINE.LSP) is to digitize 2-dimensional structuer forms in the interactive mode considering error handling, and the other one (IMPOST.LSP) is for superimposing and visualizing the digitized plan data to 3-dimension solids & surfaces referring to topographic elevations of meshes in digital terrain model. By applying utilities to present site, the followings may be described. 1) The utility DSLINE.LSP for digitizing simplified building structure form were proved to be easy to input data of polygons including orthogonal edges by handling user coordinates system and checking invalid intersection and default colsing. 2) IMPOST.LSP utility for superimposing and visualizing tool were proved to be more complicated and speedy in calculating process compared with a practical application of modeling tool before rendering process in landscape simulation of built environment on topographic relief, on specially mesospace level of assessment.

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Fairing B-spline Surfaces Using Optimization Technique (최적화 기법을 이용한 곡면페어링)

  • park, S.K.;Lee, K.W.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.1 no.3
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    • pp.95-108
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    • 1993
  • The needs for smooth curves and surfaces are increasing in modeling cars, ships, airplanes, and other consumer products either for aesthetic or functional purpose. However, the curves and surfaces generated by conventional modeling methods usually exhibit an unwanted behavior due to digitizing errors or inadequate generation method, and thus much time and extra effort is spent afterwards to get the faired results. The objective of this work is to develop a fairing scheme by which well refined shape of a surface can be acquired with detecting and removing the shape imperfections of the given surface represented by NURBS. The fairing scheme is based on an optimization process in which the control points of the given surface are repositioned to minimize the integration of the jumps(perturbations) of the unit normal vectors at all surface points.

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A Study on 3-D Shape Measurement and Application by Using Digital Projection Moire (II) (디지털 영사식 무아레를 이용한 3차원 형상 측정과 응용에 관한 연구(II))

  • Ryu, Weon-Jae;Kang, Young-June;Rho, Hyung-Min;Lee, Dong-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.5
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    • pp.62-67
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    • 2007
  • A simple dimension measuring method for the measurement of human bust has been developed using projection moire. The 3-D data of a human bust was calculated from the 2dimensional image information obtained by the stripe using projection moire. The creation of 3-D geometric shape by digitizing real objects has been widely investigated in reverse engineering(RE). This procedure generally consists of three basic steps: data capture, data alignment and model reconstruction. In order to achieve a complete model, multiple scans must be taken and aligned.

모아레간섭을 이용한 3차원 형상측정

  • 박현구;김승우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1991.04a
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    • pp.195-201
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    • 1991
  • This paper presents appliation of optical moire topography to mesuring force profiles of dies and clay models for practical use in the field of production engineering. Moire topography has been studied intensively during last few decades in the area of optical physics and its mathmatical theory has now been established. In this study, two optical configurations are suggested in which resultant moire fringes can be readily analyzed, so that 3D proviles of the models are constructed through a series of image processing by suing ma chine vision techniques. Experimental results demonstreated by using a micro- computer and CCD camera show 0.05mm measuring spatial resulution, so that the optical method can effectively adopted in order to overcome many difficulties arising when using the existing contact-type digitizing methods.

A Study on the calculating the amount of updating Digital Map using Remotely Sensed Data (원격탐사자료를 이용한 수치지도 수정ㆍ갱신 물량 산출 방안 연구)

  • 윤여상;최종현;강인구
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.11a
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    • pp.465-471
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    • 2004
  • The digital map expresses natural topographies and artificial things with 3D position coordinates in the computer such as the road, railway, building, river, mountain, paddy and dryland. Therefore, the digital map is regarded as an important factor in the information-oriented society. However, it is difficult to maintain the most recent topographic information all the times because of restricted budget and time. For that, the efficient method corresponded with the digital map should be presented. This study aims to suggest the way to make an estimate of updating cost for 1:5,000 scale digital map by using remotely sensed data. To predict updating area of the digital map, the screen digitizing method was applied to the overlapped images and digital map

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Tool-Path Generation in NC Machining of Automobile Panel Die (자동차 판넬 금형의 NC 가공을 위한 공구 경로 생성)

  • Lee, C.S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.2 no.5
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    • pp.74-84
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    • 1994
  • This paper discusses a method to generate the tool path for NC machining of automobile panel dies. The source data representing a panel die may be generated from digitizing machines, other CAD/CAM systems via IGES files, of compound surface models. From the source data, three types of interferencefree tool paths are generated automatically ; a parallel (Cartesian), an isometric, and a pencil cutting tool path. For the interference-free tool path, a polyhedral model composed of several triangles, and an 'offset triangle' approach are exploited. Finally, some practical examples are illustrated.

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A Research of Zigbee & Embedded System for Real Time Production System (실시간생산정보시스템을 위한 지그비와 임베디드시스템에 관한 연구)

  • Park, Ju-Sik;Jeong, Yeong-Deuk;Sin, Hyeon-Jae
    • Proceedings of the Safety Management and Science Conference
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    • 2012.04a
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    • pp.561-571
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    • 2012
  • In this study, which is the basis for industrial presses to target small and medium enterprises with production information system is designed. Production information in real time on-site digitizing and transmitting data to a standard PC is to base operations. Personnel management, safety management, production management is to increase the efficiency. Therefore, at low cost is to encourage computerization within the company. These embedded systems and wireless communication module has a database management program installed in order to raise productivity and competitiveness will improve.

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