• 제목/요약/키워드: Projection area

검색결과 356건 처리시간 0.023초

주거용 건물에서의 투영법에 의한 조망의 정량적 분석에 관한 연구 (A Study on the Quantitative Analysis of View by the Projection Method in the Residential Buildings)

  • 김용이;김광우
    • 한국주거학회논문집
    • /
    • 제14권5호
    • /
    • pp.37-46
    • /
    • 2003
  • The quantitative analysis of view tells how surroundings and sky are showed, and requires understanding of visual perception and three dimensional information of buildings. The visual perception and the existing projection methods for view analysis are examined. The results of this study are as follows: The visual perception on the size is determined by the visual angle, which can be described as a solid angle. The analysis of view by planar projection can be narrow-sighted according to the size of the window and the location of the viewpoint, which will cause the obstacles in the normal direction of the window interfere the view. For the analysis of view by fisheye projection, the area around the focus point is calculated wider than other areas, and so the view ratio depends on the position of the focus point. When analyzing sky view by dividing the sky vault into the differential area, the distortion by projection can be minimized.

TM 및 다면체 투영법(投影法)의 비교고찰(比較考察) (A Study on the Comparision Between Map Projection Methods of TM and Polyhedric)

  • 박외근
    • 대한공간정보학회지
    • /
    • 제6권2호
    • /
    • pp.119-132
    • /
    • 1998
  • 지형 및 공간에 관한 많은 양의 정보들은 축척 또는 활용목적 등에 따라 분류되어 다양한 형태의 지도로 만들어지고 있다. 그러나 단일 투영법을 근거로 생산되는 지도가 축척 및 활용목적 등의 다양한 요구조건을 만족시키는 데에는 적합하다고 할 수 없다. 따라서 본 논문에서는 중 대 축척인 1/50,000, 1/25,000, 1/5,000, 1/1,000 지도를 제작하는데 활용되고 있는 기존의 TM 투영법에 대해서 다면체 투영법과 비교 분석하여 다면체 투영법의 활용가능성을 확인해 보고자 하였다. 연구의 수행방식은 타원체면에서 자오선 호장, 평행권 호장 그리고 타원체 면적을 계산하고, 이들 값을 TM과 다면체투영법을 활용하여 직교 평면에 투영하고 타원체 및 투영평면에서 투영 왜곡량을 산출하였다. 또한 지도의 축척별 오차의 허용범위를 규정하고, 두 가지의 투영법에 따른 왜곡량을 지도의 축척별 오차의 허용범위를 결정하였다.

  • PDF

Metal Area Segmentation in X-ray CT Images Using the RNA (Relevant Neighbor Ar ea) Principle

  • Kim, Youngshin;Kwon, Hyukjoon;Kim, Joongkyu;Yi, Juneho
    • 한국멀티미디어학회논문지
    • /
    • 제15권12호
    • /
    • pp.1442-1448
    • /
    • 2012
  • The problem of Metal Area Segmentation (MAS) in X-ray CT images is a very hard task because of metal artifacts. This research features a practical yet effective method for MAS in X-ray CT images that exploits both projection image and reconstructed image spaces. We employ the Relevant Neighbor Area (RNA) idea [1] originally developed for projection image inpainting in order to create a novel feature in the projection image space that distinctively represents metal and near-metal pixels with opposite signs. In the reconstructed result of the feature image, application of a simple thresholding technique provides accurate segmentation of metal areas due to nice separation of near-metal areas from metal areas in its histogram.

컴퓨터 시각을 이용한 돼지 무게 예측시스템의 개발 (Development of a Pig's Weight Estimating System Using Computer Vision)

  • 엄천일;정종훈
    • Journal of Biosystems Engineering
    • /
    • 제29권3호
    • /
    • pp.275-280
    • /
    • 2004
  • The main objective of this study was to develop and evaluate a model for estimating pigs weight using computer vision for improving the management in Korean swine farms in Korea. This research was carried out in two steps: 1) to find a model that relates the projection area with the weight of a pig; 2) to implement the model in a computer vision system mainly consisted of a monochrome CCD camera, a frame grabber and a computer system for estimating the weight of pigs in a non-contact, real-time manner. The model was developed under an important assumption there were no observable genetic differences among the pigs. The main results were: 1) The relationship between the projection area and the weight of pigs was W = 0.0569 ${\times}$ A - 32.585($R^2$ = 0.953), where W is the weight in kg; A is the projection area of a pig in $\textrm{cm}^2$; 2) The model could estimate the weight of pigs with an error less than 3.5%.

Method and Apparatus for Digital Auto Convergence of Projection Video Display

  • Tai, Wen-Chih;Mo, Chi-Neng;Juan, Chang-Jung;Tsai, Ming-Jong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
    • /
    • pp.1171-1174
    • /
    • 2005
  • This thesis provides a new digital convergence method and apparatus which uses area photo sensor and new analog to digital algorithmic to identify the correct digital pattern position factor of the projection system. This method and apparatus can be applied to the convergence correction in a TV receiver with a display that comprises a display screen with photo sensors positioned adjacent to screen edges. It also can be applied to the manufacture process detection of the projection system to adjust the associative convergence parameter. In this paper, demonstrate how this convergence detecting algorithmic was implemented with four area photo sensors of special designed pattern to the rear projection CRT TV.

  • PDF

원근 왜곡 보정의 실시간 구현 방법 (Realtime Implementation Method for Perspective Distortion Correction)

  • 이동석;김남규;권순각
    • 한국멀티미디어학회논문지
    • /
    • 제20권4호
    • /
    • pp.606-613
    • /
    • 2017
  • When the planar area is captured by the depth camera, the shape of the plane in the captured image has perspective projection distortion according to the position of the camera. We can correct the distorted image by the depth information in the plane in the captured area. Previous depth information based perspective distortion correction methods fail to satisfy the real-time property due to a large amount of computation. In this paper, we propose the method of applying the conversion table selectively by measuring the motion of the plane and performing the correction process by parallel processing for correcting perspective projection distortion. By appling the proposed method, the system for correcting perspective projection distortion correct the distorted image, whose resolution is 640x480, as 22.52ms per frame, so the proposed system satisfies the real-time property.

산촌지역 인구변동의 특성 분석과 장래 추계 (A Study on Population Change and Projection in Korea Mountainous Area)

  • 민경택;김명은
    • 한국산림과학회지
    • /
    • 제103권4호
    • /
    • pp.670-678
    • /
    • 2014
  • 이 연구는 코호트 변화율법을 이용하여 우리나라 산촌지역 인구변동의 특성을 분석하고 장래 산촌인구를 추계한 것이다. 분석대상이 되는 산촌은 산림청에서 지정한 산촌진흥지역으로, 산림면적 비율 70% 이상, 인구밀도 111인/$km^2$, 경지면적 비율 21% 이하인 읍 면으로 정의한다. 산촌의 인구변동 특성을 살펴보면 지난 20년 간 산촌 인구는 급격히 감소하였고 노령화 지수는 상승하였다. 연령별로는 10~30대 젊은 층의 인구 유출이 많고 40대 이상 장년층의 유입이 증가하였다. 젊은 세대 인구가 감소하는 것은 교육과 취업을 위해 도시로 이동하는 경우가 많기 때문이며, 장년층 인구 증가는 귀농 귀촌에 대한 관심 증대의 영향으로 생각된다. 이러한 추세가 지속된다면 산촌인구는 2030년에 68만 명, 산촌의 노령화 지수는 1,035로 상승하여 국토의 균형 발전과 산림의 지속가능한 경영에 문제를 초래할 것이다. 따라서 산촌경제 활성화와 안정화를 위한 정책적 개입이 필요하다.

MEASURING CROWN PROJECTION AREA AND TREE HEIGHT USINGLIDAR

  • Kwak Doo-Ahn;Lee Woo-Kyun;Son Min-Ho
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
    • /
    • pp.515-518
    • /
    • 2005
  • LiDAR(Light Detection and Ranging) with digital aerial photograph can be used to measure tree growth factors like total height, height of clear-length, dbh(diameter at breast height) and crown projection area. Delineating crown is an important process for identifying and numbering individual trees. Crown delineation can be done by watershed method to segment basin according to elevation values of DSMmax produced by LiDAR. Digital aerial photograph can be used to validate the crown projection area using LiDAR. And tree height can be acquired by image processing using window filter$(3cell\times3cell\;or\;5cell\times5cell)$ that compares grid elevation values of individual crown segmented by watershed.

  • PDF

최대 및 평균 구상흑연크기에 의한 구상흑연주철재의 피로강도의 평가 (Evaluation of Fatigue Strength in Ductile Cast Iron by Maximum and Mean Size of Graphite)

  • 윤명진
    • 한국기계가공학회지
    • /
    • 제11권1호
    • /
    • pp.82-87
    • /
    • 2012
  • For different ferrite-pearlite matrix structure, contain more than 90% spheroidal ratio of graphite, GCD 45-3, GCD 50, GCD 60 series and 70%, 80%, 90% spheroidal ratio of graphite, GCD 40, GCD 45-1, GCD 45-2 series, this paper has carried out rotary bending fatigue test, estimated maximum and mean size of spheroidal graphite, investigated correlation. It was concluded as follows. (1) Fatigue limit in $10^7$cycles and numbers of spheroidal graphite per 1$mm^2$ was linear relation. (2) projection area of graphite can be used to predict fatigue limit of Ductile Cast Iron. The Statistical distribution of extreme values of projection area of defects may be used as a guideline for the control of inclusion size in the steelmaking processes.

전사방식 광조형 시스템의 해상도 최적화를 통한 출력물의 정밀도 향상 (Accuracy Improvement of Output in Projection Stereolithography by Optimizing Projection Resolution)

  • 김영흠;김규언;이치범
    • 한국생산제조학회지
    • /
    • 제24권6호
    • /
    • pp.710-717
    • /
    • 2015
  • Projection stereolithography is an additive manufacturing method that uses beam projection to cure the photo-reactive resin used. The light source of a cross-section layer-form illuminates photo-curable resin for building a three-dimensional (3D) model. This method has high accuracy and a fast molding speed because the processing unit is a face instead of a dot. This study describes a Scalable Projection Stereolithography 3D Printing System for improving the accuracy of the stereolithography. In a conventional projection 3D printer, when printing a small sized model, many pixels are not used in the projection or curing. The proposed system solves this problem through an optical adjustment, and keeps using the original image as possible as filling the whole projection area. The experimental verification shows that the proposed system can maintain the highest level of precision regardless of the output size.