• 제목/요약/키워드: Shape feature

검색결과 1,052건 처리시간 0.034초

특징형상에 기반한 공정설계를 위한 공차 모델러 개발 (A Development of the Tolerance Modeler for Feature-based CAPP)

  • 김재관;노형민;이수홍
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2000년도 추계학술대회 논문집
    • /
    • pp.267-271
    • /
    • 2000
  • A part definition must not only provide shape information of a nominal part but also contain non-shape information such as tolerances, surface roughness and material attributes. Although machining features are useful for suitable shape information for process reasoning in the CAPP, they need to be integrated with tolerance information for effective process planning. We develop the tolerance modeler that efficiently integrates machining features with tolerance information for feature-based CAPP It is based on the association of machining features, tolerance features. and tolerances Tolerance features, where tolerances are assigned, are classified into two types; one is the face that is a topological entity on a solid model and the other is the functional geometry that is not referenced to topological entities. The functional geometry is represented by using machining features All the data for representing tolerance information with machining features are stored completely and unambiguously in the independent tolerance structure. The developed tolerance modeler is implemented as a module of a comprehensive feature-based CAPP system.

  • PDF

확장형 이동창을 이용한 지도 선형 개체의 분할 기법 연구 (Line Segmentation Method using Expansible Moving Window for Cartographic Linear Features)

  • 박우진;이재은;유기윤
    • 한국측량학회:학술대회논문집
    • /
    • 한국측량학회 2010년 춘계학술발표회 논문집
    • /
    • pp.5-6
    • /
    • 2010
  • Needs for the methodology of segmentation of linear feature according to the shape characteristics of line feature are increasing in cartographic linear generalization. In this study, the line segmentation method using expansible moving window is presented. This method analyzes the generalization effect of line simplification algorithms depend on the line characters of linear feature and extracts the sections which show exclusively low positional error due to a specific algorithm. The description measurements of these segments are calculated and the target line data are segmented based on the measurements. For segmenting the linear feature to a homogeneous section, expansible moving window is applied. This segmentation method is expected to be used in the cartographic map generalization considering the shape characteristics of linear feature.

  • PDF

The Optimal Bispectral Feature Vectors and the Fuzzy Classifier for 2D Shape Classification

  • Youngwoon Woo;Soowhan Han;Park, Choong-Shik
    • 한국지능정보시스템학회:학술대회논문집
    • /
    • 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
    • /
    • pp.421-427
    • /
    • 2001
  • In this paper, a method for selection of the optimal feature vectors is proposed for the classification of closed 2D shapes using the bispectrum of a contour sequence. The bispectrum based on third order cumulants is applied to the contour sequences of the images to extract feature vectors for each planar image. These bispectral feature vectors, which are invariant to shape translation, rotation and scale transformation, can be used to represent two-dimensional planar images, but there is no certain criterion on the selection of the feature vectors for optimal classification of closed 2D images. In this paper, a new method for selecting the optimal bispectral feature vectors based on the variances of the feature vectors. The experimental results are presented using eight different shapes of aircraft images, the feature vectors of the bispectrum from five to fifteen and an weighted mean fuzzy classifier.

  • PDF

표적분할 신뢰도 값 기반의 형태특징과 지역특징을 이용한 차량표적 분류기법 연구 (A Study on Vehicle Target Classification Method Using Both Shape and Local Features with Segmentation Reliability)

  • 양동원;이용헌;곽동민
    • 한국군사과학기술학회지
    • /
    • 제20권1호
    • /
    • pp.40-47
    • /
    • 2017
  • To classify the vehicle targets automatically using thermal images, there are usually two main categories of feature extraction method, local and shape feature extraction methods. Since thermal images have less texture information than color images, the shape feature extraction method is useful when the segmentation results are correct. However, if there are some errors in target segmentation, the shape feature may contain some errors, then the classification accuracy can be decreased. To overcome these problems, in this paper, we propose the segmentation reliability estimation method for target classification. The segmentation reliability can be estimated by using the difference information of average intensities and edge energies between the target and the background area. The estimated segmentation reliability is applied in the decision level fusion method of classification results using both shape and local features. Experiment results using the thermal images of the vehicle targets (main battle tank, armored personnel carrier, military truck, and an estate car) show that the proposed classification method and the segmentation reliability estimation method have a good performance in classification accuracy.

ASM-LK Optical Flow 기반 최적 얼굴정서 특징분석 기법 (Optimal Facial Emotion Feature Analysis Method based on ASM-LK Optical Flow)

  • 고광은;박승민;박준형;심귀보
    • 한국지능시스템학회논문지
    • /
    • 제21권4호
    • /
    • pp.512-517
    • /
    • 2011
  • 얼굴영상에서 나타나는 정서특징을 분석하기 위하여 본 논문에서는 Active Shape Model (ASM)과 Lucas-Kanade (LK) optical flow 기법을 기반으로 하는 특징검출 및 분석방법을 제안한다. Facial Action Coding System에 근거하여 묘사된 정서적 특징을 고려하여, 특징이 분포하는 영역에 위치한 다수의 landmark로 shape 모델을 구성하고 모델에서 각 Landmark를 중심으로 하는 움직임 벡터 윈도우 내부의 픽셀에 대한 LK 기법을 통해 optical flow 벡터를 추출한다. 추출된 움직임 벡터의 방향성 조합에 근거하여 얼굴정서특징을 shape 모델로 표현할 수 있으며, 베이지안 분류기라는 확률 기반 추론기법을 기반으로 정서적 상태에 대한 추정할 수 있다. 또한, 정서특징분석과정의 연산 효율성과 정확성 향상을 도모하기 위하여 common spatial pattern (CSP) 분석기법을 적용하여 정서상태 별로 상관성이 높은 특징만으로 구성된 최적정서특징을 추출한다.

맥파의 특징점 인식과 파형의 분류에 관한 연구 (The Study on the Feature Point Recognition and Classification of Radial Pulse)

  • 길세기;김낙환;이상민;박승환;홍승홍
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1999년도 하계종합학술대회 논문집
    • /
    • pp.555-558
    • /
    • 1999
  • In this paper, Ire present the result of feature points recognition and classification of radial pulse by the shape of pulse wave. The recognition algorithm use the method which runs in parallel with both the data of ECG and differential pulse simultaneously to recognize the feature points. Also we specified 3-time elements of pulse wave as main parameters for diagnosis and measured them by execution of algorithm. then we classify the shape of radial pulse by existence and position of feature points.

  • PDF

얼굴 특징점 자동 추출 오류에 강인한 3차원 얼굴 복원 방법 (A 3D Face Reconstruction Method Robust to Errors of Automatic Facial Feature Point Extraction)

  • 이연주;이성주;박강령;김재희
    • 대한전자공학회논문지SP
    • /
    • 제48권1호
    • /
    • pp.122-131
    • /
    • 2011
  • 최근에 널리 사용되고 있는 단일 영상 기반의 3차원 얼굴 복원 방법인 변형 가능한 3차원 얼굴 형상 모델(3D morphable shape model)은 입력 영상으로부터 2차원 얼굴 특징점들을 정확하게 추출할 경우, 입력 얼굴과 유사한 3차원 얼굴 형상을 생성할 수 있다. 그러나 실시간 3차원 얼굴 복원 시스템과 같이 사용자의 협조가 불가능한 경우에는 자동으로 얼굴 특징점들을 추출해야 하기 때문에, 특징점 추출 오류가 발생하여 정확한 3차원 얼굴 형상을 생성하기 어려운 문제가 있다. 이러한 문제를 해결하기 위해서, 본 논문에서는 특징점 추출 시 오추출 특징점과 정추출 특징점을 자동으로 분류하고, 정추출 특징점들만을 이용하여 3차원 얼굴을 복원하는 방법을 제안하였다. 실험결과에서는 특징점 자동 추출 오류를 고려하지 않은 기존 방법과 비교한 결과, 제안방법의 3차원 얼굴 복원 성능이 크게 향상되었음을 확인하였다.

색상과 형태를 이용한 내용 기반 영상 검색 (Content-based Image Retrieval Using Color and Shape)

  • 하정요;최미영;최형일
    • 한국컴퓨터정보학회논문지
    • /
    • 제13권1호
    • /
    • pp.117-124
    • /
    • 2008
  • 본 논문에서는 색상정보와 형태정보를 이용한 내용기반 영상 검색방법을 제안한다. 이미지의 한 가지 특징만을 고려한 내용 기반 이미지 검색은 두 가지 이상의 특징 정보를 이용했을 때와 비교하여 정확도가 떨어져 성능을 저하시킬 수 있다. 따라서 여러 검색 시스템에서는 색상이나 형태, 질감 등과 같은 이미지의 다양한 특징들을 혼합하여 검색에 이용하고 있다. 본 연구는 각 영상의 Hue값에 대한 색상정보와 CSS(Curvature Scale Space)를 이용한 형태정보를 사용한다. 각 영상들의 특징 정보와 데이터베이스에 저장된 영상들의 특징 정보들을 비교하여 유사도 순위에 따라 후보영상들이 검색된다. 실험 결과 색상정보나 형태정보 한가지의 특징만을 사용한 경우 보다 정확도와 재현율면에서 사용자가 원하는 이미지와 보다 유사한 결과를 검출할 수 있었다.

  • PDF

iOS 플랫폼에서 Active Shape Model 개선을 통한 얼굴 특징 검출 (Improvement of Active Shape Model for Detecting Face Features in iOS Platform)

  • 이용환;김흥준
    • 반도체디스플레이기술학회지
    • /
    • 제15권2호
    • /
    • pp.61-65
    • /
    • 2016
  • Facial feature detection is a fundamental function in the field of computer vision such as security, bio-metrics, 3D modeling, and face recognition. There are many algorithms for the function, active shape model is one of the most popular local texture models. This paper addresses issues related to face detection, and implements an efficient extraction algorithm for extracting the facial feature points to use on iOS platform. In this paper, we extend the original ASM algorithm to improve its performance by four modifications. First, to detect a face and to initialize the shape model, we apply a face detection API provided from iOS CoreImage framework. Second, we construct a weighted local structure model for landmarks to utilize the edge points of the face contour. Third, we build a modified model definition and fitting more landmarks than the classical ASM. And last, we extend and build two-dimensional profile model for detecting faces within input images. The proposed algorithm is evaluated on experimental test set containing over 500 face images, and found to successfully extract facial feature points, clearly outperforming the original ASM.

형상인식에 의한 다면체모델의 NC 가공을 위한 소개 및 셋업계획 (Workpart and Setup Planning for NC Machining of Prismatic Model:Feature-Based Approach)

  • 지우석;서석환;강재관
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
    • /
    • pp.1078-1083
    • /
    • 1992
  • Extracting the process planning information from the CAD data is the key issue in integrated CAD/CAM system. In this paper, we develop algorithms for extracting the shape and setup configuration for NC machining of prismatic parts. In determining the workpart shape, the minimum-enclosing condept is applied so that the material waste is minimized. To minimize the number of setups, feature based algorithm is developed considrint the part shape, tool shape, and tool approach direction. The validity and effectiveness of the developed algorithms were tested by computer simulations.

  • PDF