• 제목/요약/키워드: rotation transform.

검색결과 225건 처리시간 0.032초

전동휠체어 자동 주행을 위한 복도영상 해석 (The Corridor Scene Analysis for a Motorized Wheelchair's Automatic Locomotion)

  • 문철홍;한영환;홍승홍
    • 대한의용생체공학회:의공학회지
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    • 제15권1호
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    • pp.27-34
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    • 1994
  • In this paper. a way to analysis a corridor scene for a vehicle's automatic locomotion is presented In general, it's necessary for a vision system of vehicles to identify its positions in given environments. The suggested algorithm is to decide base lines of a corridor image using the vanishing point finding. Feature points are extracted on the base line using a base line extraction tree. This algorithm is suitable for a motorized wheelchair's self locomotion in a building.

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Comparisons of Linear Characteristic for Shape of Stator Teeth of Hall Effect Torque Sensor

  • Lee, Boram;Kim, Young Sun;Park, Il Han
    • Journal of Magnetics
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    • 제17권4호
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    • pp.285-290
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    • 2012
  • Electric Power Steering (EPS) system is superior to conventional Hydraulic Power Steering (HPS) system in aspect of fuel economy and environmental concerns. The EPS system consists of torque sensor, electric motor, ECU (Electric Control Unit), gears and etc. Among the elements, the torque sensor is one of the core technologies of which output signal is used for main input of EPS controller. Usually, the torque sensor has used torsion bar to transform torsion angle into torque and needs linear characteristic in terms of flux variation with respect to rotation angle of permanent magnet. The torsion angle of both ends of a torsion bar is measured by a contact variable resistor. In this paper, the sensor is accurately analyzed using 3D finite element method and its characteristics with respect to four different shapes of the stator teeth are compared. The four shapes are rectangular, triangular, trapezoidal and circular type.

GPU-Based Optimization of Self-Organizing Map Feature Matching for Real-Time Stereo Vision

  • Sharma, Kajal;Saifullah, Saifullah;Moon, Inkyu
    • Journal of information and communication convergence engineering
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    • 제12권2호
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    • pp.128-134
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    • 2014
  • In this paper, we present a graphics processing unit (GPU)-based matching technique for the purpose of fast feature matching between different images. The scale invariant feature transform algorithm developed by Lowe for various feature matching applications, such as stereo vision and object recognition, is computationally intensive. To address this problem, we propose a matching technique optimized for GPUs to perform computations in less time. We optimize GPUs for fast computation of keypoints to make our system quick and efficient. The proposed method uses a self-organizing map feature matching technique to perform efficient matching between the different images. The experiments are performed on various image sets to examine the performance of the system under varying conditions, such as image rotation, scaling, and blurring. The experimental results show that the proposed algorithm outperforms the existing feature matching methods, resulting in fast feature matching due to the optimization of the GPU.

A New Scheme for Watermarking Engineering Graph

  • Zhanchuan, Cai;Wei, Sun;Changzhen, Xiong;Dongxu, Qi
    • International Journal of CAD/CAM
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    • 제6권1호
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    • pp.99-104
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    • 2006
  • Engineering graph plays an important role in design and manufacture, such as architecture, machinery, manufacture, military. However, almost no persons consider the security and copyright of two-dimensional engineering graph. A novel method for two-dimensional engineering graph watermark based U system is proposed in this paper. Watermarks generated by this technique can be successfully extracted even after rotation, translation and scaling transform.

고무타이어 자동분류를 위한 돌출문자 인식 (Recognition of Raised Characters for Automatic Classification of Rubber Tires)

  • 함영국;강민석;정홍규;박래홍;박귀태
    • 전자공학회논문지B
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    • 제31B권4호
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    • pp.77-87
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    • 1994
  • This paper presents recognition of raised alphanumeric markings on rubber tires for their automatic classification. Raised alphanumeric markings on rubber tires have different characteristics as compared to those of printed characters. In the preprocessing step, we first determine the rotation angle using the Hough transform and align markings, then separate each character using vertical and horizontal projections. In the recognition step, we use several features such as width of a character, cross point, partial projection, and distance feature to recognize characters hierarchically. The computer simulation result shows that the proposed system can be successfully applied to the industrial automation of rubber tires classification.

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가상환경을 위한 파노라마 생성에 관한 연구 (Panoramic Image Generation for the Virtual Environment)

  • 김태은
    • 디지털콘텐츠학회 논문지
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    • 제8권3호
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    • pp.365-370
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    • 2007
  • 본 논문에서는 환경 탐색을 위한 영상 기반 환경을 자동으로 생성하기 위한 새로운 모자이크 기법을 제안 한다. 제안된 방법은 영상의 투영 변환 행렬을 이용하여 한 영상 위에 다른 영상을 합성 한다. 특징 모델을 기반한 정합을 이용하여 영상을 모자이크를 구현하고 구맵핑을 통해 시각에 따라 변형되어 몰입감을 주는 영상 기반 환경을 생성한다, 특히, 취득한 영상간의 카메라 회전 성분에 강건한 기준 특징 벡터 필터링 방법을 제안하며 실험을 통해 그 유용성을 검증한다.

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신경망의 스펙트럼 분석기를 이용한 패턴 인식 (Pattern Recognition Using Spectrum Analyzer and Neural Network)

  • 김남익;한수환;전도홍
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1996년도 추계학술대회 학술발표 논문집
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    • pp.211-214
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    • 1996
  • This paper propose a method for pattern recogniton using spectrum analyzer and fuzzy ARTMAP. Contour sequences obtained from 2-D planar images represent the Euclidean distance between the centroid and all boundary pixels of the shape, and are related to the overall shape of the images. The Fourier transform of contour sequence and spectrum analyzer are used as a means of feature selection and data reduction. The three dimensional spectral feature vectors are extracted by spectrum analyzer from the FFT spectrum. These Spectral feature vectors are invariant to shape translation, rotation, and scale transformations. The fuzzy ARTMAP neural network which is combined with two fuzzy ART modules is trained and tested with these feature vectors. The experiments include 4 aircrafts and 4 industrial parts recognition process are presented to illustrate the high performance of this proposed method in the ion problems of noisv shapes.

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수소압축기 스너버 관로 내부의 맥동파 특성에 관한 연구 (A Study on Gas Pressure Fluctuation Characteristics inside Pipe Line Passing Through a Snubber at Hydrogen Compressor)

  • 심규진;이중섭;악바르 완다 알리;정한식;정효민
    • 동력기계공학회지
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    • 제10권4호
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    • pp.165-171
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    • 2006
  • An experiment to observe reduction of pressure fluctuation in the compressing system utilizing snubber has done. The experiment measured pressure at inlet and outlet of snubber. It used an air compressor as a model of hydrogen one. Snubber with buffer and snubber without buffer were used to get comprehensive comparison between both of that snubber. An analysis by using Fast Fourier Transform (FFT) method was conducted to verify working pressure frequency. With this method pure signal of static pressure was filtered from noisy signal. The experiment was run for several speeds of piston movement. It was controlled by adjustable frequency regulator that controled rotation of actuator motor. This was connected to the piston-reciprocating compressor with V-belt. From result obtained, the fluctuation was increasing proportionally when frequency of driver motor was increased.

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Affine Local Descriptors for Viewpoint Invariant Face Recognition

  • Gao, Yongbin;Lee, Hyo Jong
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2014년도 춘계학술발표대회
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    • pp.781-784
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    • 2014
  • Face recognition under controlled settings, such as limited viewpoint and illumination change, can achieve good performance nowadays. However, real world application for face recognition is still challenging. In this paper, we use Affine SIFT to detect affine invariant local descriptors for face recognition under large viewpoint change. Affine SIFT is an extension of SIFT algorithm. SIFT algorithm is scale and rotation invariant, which is powerful for small viewpoint changes in face recognition, but it fails when large viewpoint change exists. In our scheme, Affine SIFT is used for both gallery face and probe face, which generates a series of different viewpoints using affine transformation. Therefore, Affine SIFT allows viewpoint difference between gallery face and probe face. Experiment results show our framework achieves better recognition accuracy than SIFT algorithm on FERET database.

스테레오 카메라 기반 트윈 카메라 모듈 시스템 설계 및 구현 (Design and Implementation Stereo Camera based Twin Camera Module System)

  • 김태연
    • 한국정보전자통신기술학회논문지
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    • 제12권6호
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    • pp.537-546
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    • 2019
  • 본 논문에서는 휴대하기 편하고 3D 콘텐츠 제작이 용이한 트윈 카메라 모듈 시스템을 구현하고자 하였다. 제안한 트윈 카메라 모듈 시스템은 2D 스테레오 카메라로 부터 입력되는 영상을 변환하여 3차원 영상으로 출력할 수 있는 시스템이다. 본 눈문에서 제안한 시스템의 성능평가를 위해 Test Platform을 이용하여 좌, 우 두 개의 렌즈로 촬영된 스테레오 입체 영상의 좌, 우 영상 간의 시차에 따른 회전(Rotation), 기울기(Tilt)에 대한 보정을 평가하였다. 또한 SIFT(Scale Invariant Feature Transform) 알고리즘을 이용하여 3D 입체 영상의 거리오차(Depth Error)를 검증하여 트윈 카메라 모듈 시스템의 효율성을 검증하고자 하였다. 본 논문에서 제안한 트윈 카메라 모듈 시스템은 촬영된 영상을 3D 입체 영상과 준비 영상으로 변화하여 외부에 출력하면 각기 다른 3D 입체 영상 제작 방식에 따른 출력장치에 맞춰 디스플레이가 가능하다. 또한 생성된 영상을 준비 영상과 입체 영상을 각기 다른 채널을 통해 출력하여 많은 제품에 적용하기 쉽고 간편하게 3D 입체 영상 콘텐츠를 제작하는데 이용할 수 있을 거라 기대한다.