• Title/Summary/Keyword: Geometrical Feature

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Intelligent Simulation of Three-Dimensional Forging Process (삼차원 단조공정의 지능적 시뮬레이션)

  • Lee, M.C.;Joun, M.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.155-159
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    • 2007
  • We conduct intelligent simulation of three-dimensional forging processes in this paper. A new remeshing technique is employed for this purpose. Not only the state variables including strain and strain-rate but also the geometrical features including die-material contact conditions and the characteristic lines or surfaces are taken into account during remeshing. The presented approach is applied to the Baden-Baden benchmark test example and its influence on the simulated results is discussed particularly in terms of the deformed shape with emphasis on the characteristic line.

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Face Extraction using Genetic Algorithm, Stochastic Variable and Geometrical Model (유전 알고리즘, 통계적 변수, 기하학적 모델에 의한 얼굴 영역 추출)

  • 이상진;홍준표이종실홍승홍
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.891-894
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    • 1998
  • This paper introduces an automatic face region extraction method. This method consists of two part: face recognition and extraction of facial organs which are eye, eyebrow, nose and mouth. In first stage, we use genetic algorithms(GAs) to get face region in complex background. In second stage, we use Geometrical Face Model to textract eye, eyebrow, nose and mouth. In both stage, stochastic component is used to deal with the problems caused by had lighting condition. According to this value, blurring number is determined. Average Computation time is less than 1 sec, and using this method we can extract facial feature efficiently from several images which has different lightning condition.

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A Study on Scale-Invariant Features Extraction and Distance Measurement for Localization of Mobile Robot (이동로봇의 위치 추정을 위한 스케일 불변 특징점 추출 및 거리 측정에 관한 연구)

  • Jung, Dae-Seop;Jang, Mun-Suk;Ryu, Je-Goon;Lee, Eung-Hyuk;Shim, Jae-Hong
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.625-627
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    • 2005
  • Existent distance measurement that use camera is method that use both Stereo Camera and Monocular Camera, There is shortcoming that method that use Stereo Camera is sensitive in effect of a lot of expenses and environment variables, and method that use Monocular Camera are big computational complexity and error. In this study, reduce expense and error using Monocular Camera and I suggest algorithm that measure distance, Extract features using scale Invariant features Transform(SIFT) for distance measurement, and this measures distance through features matching and geometrical analysis, Proposed method proves measuring distance with wall by geometrical analysis free wall through feature point abstraction and matching.

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Similarity Measurement Using Open-Ball Scheme for 2D Patterns in Comparison with Moment Invariant Method (Open-Ball Scheme을 이용한 2D 패턴의 상대적 닮음 정도 측정의 Moment Invariant Method와의 비교)

  • Kim, Seong-Su
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.1
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    • pp.76-81
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    • 1999
  • The degree of relative similarity between 2D patterns is obtained using Open-Ball Scheme. Open-Ball Scheme employs a method of transforming the geometrical information on 3D objects or 2D patterns into the features to measure the relative similarity for object(patten) recognition, with invariance on scale, rotation, and translation. The feature of an object is used to obtain the relative similarity and mapped into [0, 1] the interval of real line. For decades, Moment-Invariant Method has been used as one of the excellent methods for pattern classification and object recognition. Open-Ball Scheme uses the geometrical structure of patterns while Moment Invariant Method uses the statistical characteristics. Open-Ball Scheme is compared to Moment Invariant Method with respect to the way that it interprets two-dimensional patten classification, especially the paradigms are compared by the degree of closeness to human's intuitive understanding. Finally the effectiveness of the proposed Open-Ball Scheme is illustrated through simulations.

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Evaluation of Condensation Heat Transfer Correlations for Microfin Tubes

  • Han, Dong-Hyouck;Lee, Kyu-Jung
    • International Journal of Air-Conditioning and Refrigeration
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    • v.15 no.4
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    • pp.163-168
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    • 2007
  • The feature of six existing condensation heat transfer correlations for microfin tubes were evaluated with the consideration of vapor quality, mass flux, geometries, and various refrigerants. The Kosky and Staub [15] and the Jaster and Kosky [16] correlations for smooth tube were used for the evaluation of the heat transfer enhancement factor (EF). For the prediction of zeotropic mixtures, most correlations show discrepancy with previous measurements. The Yu and Koyama [4] and the Shikazono et al. [8] correlations do not consider spiral angle effect. The Han and Lee [10] correlation shows fin height growth deteriorates heat transfer. Experimental verification to develop reliable condensation heat transfer correlation for microfin tubes is still needed with the consideration of geometrical effects and working conditions.

OBJECT RECOGNITION ALGORITHM (물체 인지 알고리즘)

  • Shon, Howoong;Cho, Hyun C;Kim, Youngkyung
    • Journal of the Korean Geophysical Society
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    • v.7 no.4
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    • pp.247-253
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    • 2004
  • In this paper, 3D recognizing algorithm which is based on the external shape feature is presented. Since many objects have the regular shape, if we posses the database of pattern and we recognize the object using the database of the object's pattern, it is possible to inspect and/or recognize the objects of many fields. This paper handles on the 3D object recognition algorithm using the geometrical pattern matching by 3D database.

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Effects of geometrical parameters on the degree of bending in two-planar tubular DYT-joints of offshore jacket structures

  • Hamid Ahmadi;Mahdi Ghorbani
    • Ocean Systems Engineering
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    • v.13 no.2
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    • pp.97-121
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    • 2023
  • Through-the-thickness stress distribution in a tubular member has a profound effect on the fatigue behavior of tubular joints commonly found in steel offshore structures. This stress distribution can be characterized by the degree of bending (DoB). Although multi-planar joints are an intrinsic feature of offshore tubular structures and the multi-planarity usually has a considerable effect on the DoB values at the brace-to-chord intersection, few investigations have been reported on the DoB in multi-planar joints due to the complexity of the problem and high cost involved. In the present research, data extracted from the stress analysis of 243 finite element (FE) models, verified based on available parametric equations, was used to study the effects of geometrical parameters on the DoB values in two-planar tubular DYT-joints. Parametric FE study was followed by a set of nonlinear regression analyses to develop six new DoB parametric equations for the fatigue analysis and design of axially loaded two-planar DYT-joints.

Adaptive Face Region Detection and Real-Time Face Identification Algorithm Based on Face Feature Evaluation Function (적응적 얼굴검출 및 얼굴 특징자 평가함수를 사용한 실시간 얼굴인식 알고리즘)

  • 이응주;김정훈;김지홍
    • Journal of Korea Multimedia Society
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    • v.7 no.2
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    • pp.156-163
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    • 2004
  • In this paper, we propose an adaptive face region detection and real-time face identification algorithm using face feature evaluation function. The proposed algorithm can detect exact face region adaptively by using skin color information for races as well as intensity and elliptical masking method. And also, it improves face recognition efficiency using geometrical face feature and geometric evaluation function between features. The proposed algorithm can be used for the development of biometric and security system areas. In the experiment, the superiority of the proposed method has been tested using real image, the proposed algorithm shows more improved recognition efficiency as well as face region detection efficiency than conventional method.

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A Facial Feature Detection using Light Compensation and Appearance-based Features (빛 보상과 외형 기반의 특징을 이용한 얼굴 특징 검출)

  • Kim Jin-Ok
    • Journal of Internet Computing and Services
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    • v.7 no.3
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    • pp.143-153
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    • 2006
  • Facial feature detection is a basic technology in applications such as human computer interface, face recognition, face tracking and image database management. The speed of feature detection algorithm is one of the main issues for facial feature detection in real-time environment. Primary factors like a variation by lighting effect, location, rotation and complex background give an effect to decrease a detection ratio. A facial feature detection algorithm is proposed to improve the detection ratio and the detection speed. The proposed algorithm detects skin regions over the entire image improved by CLAHE, an algorithm for light compensation against varying lighting conditions. To extract facial feature points on detected skin regions, it uses appearance-based geometrical characteristics of a face. Since the method shows fast detection speed as well as efficient face-detection ratio, it can be applied in real-time application to face tracking and face recognition.

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Effect of Inquiring Activities through Manipulative Materials-Experiment on Geometrical Properties Understanding and Communicative Competence (구체적 조작.실험을 통한 탐구활동이 평면도형의 성질 이해 및 수학적 의사소통능력에 미치는 영향)

  • Lim, Geun-Gwang
    • Journal of Elementary Mathematics Education in Korea
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    • v.14 no.3
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    • pp.701-722
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    • 2010
  • Students have to investigate, experiment and inquire using the manipulative materials and real-world thing for studying Geometry. Manipulative materials activities encourage to understand mathematical concept and connection of symbol. Experiment activities using the computer focused the student's intuitive and inquisitive activities because of visualization of an abstract mathematics concept. This study developed a workbook through the use of manipulative materials and computer for operating and experimenting, and suggested a method for inquiry of geometrical properties and proved an effect. Manipulative materials-experiment activities was proven effective to middle level and lower level students in understanding the geometrical properties, and was proven effective to high level and lower level students when it comes to mathematical communication ability. When students operate, at first, they have to know about the feature and information of the materials, and the teacher has to make an elaborate plan and encourages the students to discuss about this.

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