• 제목/요약/키워드: 후보점

검색결과 392건 처리시간 0.031초

A Fast Pupil Detection Using Geometric Properties of Circular Objects (원형 객체의 기하학적 특성을 이용한 고속 동공 검출)

  • Kwak, Noyoon
    • Journal of Digital Convergence
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    • 제11권2호
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    • pp.215-220
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    • 2013
  • They are well-known geometric properties of a circle that the perpendicular bisector of a chord passes through the center of a circle, and the intersection of the perpendicular bisectors of any two chords is its center. This paper is related to a fast pupil detection method capable of detecting the center and the radius of a pupil using these geometric properties at high speed when detecting the pupil region for iris segmentation. The proposed method is characterized as rapidly detecting the center and the radius of the pupil, extracting the candidate points of the circle in human eye images using morphological operations, and finding two chords using four points on the circular edge, and taking the intersection of the perpendicular bisectors of these two chords for its center. The proposed method can not only detect the center and the radius of a pupil rapidly but also find partially occluded pupils in human eye images.

Analysis of Research Trends in Mathematical Creativity Education (수학적 창의성 교육에 관한 연구 동향 분석)

  • Choi, Byoung-Hoon;Pang, Jeong-Suk
    • Journal of Gifted/Talented Education
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    • 제22권1호
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    • pp.197-215
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    • 2012
  • The purpose of this study was to analyze the research trends of 114 papers about mathematical creativity published in domestic journals from 1997 to 2011 with regard to the years, objects, subjects, and methods of such research. The research of mathematical creativity education has been studied since 2000. The frequent objects in the research were non-human, middle and high school students, elementary students, gifted students, teachers (in-service and pre-service), and kindergarteners in order. The research on the teaching methods of mathematical creativity, the general study of mathematical creativity, or the measurement and the evaluation of mathematical creativity was active, whereas that of dealing with curricula and textbooks was rare. The qualitative research method was more frequently used than the quantitative research one. The mixed research method was hardly used. On the basis of these results, this paper shows how mathematical creativity was studied until now and gives some implications for the future research direction in mathematical creativity.

A Prediction Search Algorithm in Video Coding by using Neighboring-Block Motion Vectors (비디오 코딩을 위한 인접블록 움직임 벡터를 이용한 예측 탐색 알고리즘)

  • Kwak, Sung-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제12권8호
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    • pp.3697-3705
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    • 2011
  • There is the temporal correlation of the video sequence between the motion vector of current block and the motion vector of previous block. In this paper, we propose a new prediction search algorithm for block matching using the temporal and spatial correlation of the video sequence and local statistics of neighboring motion vectors. The proposed ANBA(Adaptive Neighboring-Block Search Algorithm) determines the location of a better starting point for the search of an exact motion vector using the point of the smallest SAD(Sum of Absolute Difference) value by the predicted motion vectors of neighboring blocks around the same block of the previous frame and the current frame and use a previous motion vector. Simulation results show that PSNR(Peak-to-Signal Noise Ratio) values are improved up to the 1.06dB as depend on the video sequences and improved about 0.01~0.64dB over MVFAST and PMVFAST.

Efficient Path Finding Based on the $A^*$ algorithm for Processing k-Nearest Neighbor Queries in Road Network Databases (도로 네트워크에서 $A^*$ 알고리즘을 이용한 k-최근접 이웃 객체에 대한 효과적인 경로 탐색 방법)

  • Shin, Sung-Hyun;Lee, Sang-Chul;Kim, Sang-Wook;Lee, Jung-Hoon;Im, Eul-Kyu
    • Journal of KIISE:Databases
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    • 제36권5호
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    • pp.405-410
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    • 2009
  • This paper proposes an efficient path finding scheme capable of searching the paths to k static objects from a given query point, aiming at both improving the legacy k-nearest neighbor search and making it easily applicable to the road network environment. To the end of improving the speed of finding one-to-many paths, the modified A* obviates the duplicated part of node scans involved in the multiple executions of a one-to-one path finding algorithm. Additionally, the cost to the each object found in this step makes it possible to finalize the k objects according to the network distance from the candidate set as well as to order them by the path cost. Experiment results show that the proposed scheme has the accuracy of around 100% and improves the search speed by $1.3{\sim}3.0$ times of k-nearest neighbor searches, compared with INE, post-Dijkstra, and $na{\ddot{i}}ve$ method.

Two-step Boundary Extraction Algorithm with Model (모델 정보를 이용한 2단계 윤곽선 추출 기법)

  • Choe, Hae-Cheol;Lee, Jin-Seong;Jo, Ju-Hyeon;Sin, Ho-Cheol;Kim, Seung-Dae
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • 제39권1호
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    • pp.49-60
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    • 2002
  • We propose an algorithm for extracting the boundary of a desired object with shape information obtained from sample images. Considering global shape obtained from sample images and edge orientation as well as edge magnitude, the Proposed method composed of two steps finds the boundary of an object. The first step is the approximate segmentation that extracts a rough boundary with a probability map and an edge map. And the second step is the detailed segmentation for finding more accurate boundary based on the SEEL (seed-point extraction and edge linking) algorithm. The experiment results using IR images show robustness to low-quality image and better performance than conventional segmentation methods.

Active Shape Model-based Objectionable Image Detection (활동적 형태 모델을 이용한 유해영상 탐지)

  • Jang, Seok-Woo;Joo, Seong-Il;Kim, Gye-Young
    • Journal of Internet Computing and Services
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    • 제10권5호
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    • pp.183-194
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    • 2009
  • In this paper, we propose a new method for detecting objectionable images with an active shape model. Our method first learns the shape of breast lines through principle component analysis and alignment as well as the distribution of intensity values of corresponding landmarks, and then extracts breast lines with the learned shape and intensity distribution. To accurately select the initial position of active shape model, we obtain parameters on scale, rotation, and translation. After positioning the initial location of active shape model using scale and rotation information, iterative searches are performed. We can identify adult images by calculating the average of the distance between each landmark and a candidate breast line. The experiment results show that the proposed method can detect adult images effectively by comparing various results.

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R-wave Detection Algorithm in ECG Signal Using Adaptive Refractory Period (ECG 신호에서 적응적 불응기를 이용한 R-wave 검출 알고리즘)

  • Kim, Jung-Joon;Kim, Jin-Sub;Park, Kil-Houm
    • Journal of the Institute of Electronics and Information Engineers
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    • 제50권5호
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    • pp.242-250
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    • 2013
  • In this paper, R-wave detection algorithm using refractory period to reflect the depolarization and repolarization of the myocardial cells of the heart is proposed. The proposed algorithm detects R-peaks using the features of R-wave and variable refractory period. First, the proposed algorithm extracts candidate R-peaks that have a relatively high potential and calculates the refractory period based on the kurtosis and potential for candidate R-peaks. Next, R-peak is determined by morphological features of the R-wave within the refractory period. In addition, due to less computation in the proposed algorithm, real-time processing is possible. The algorithm is applied to all records of the MIT-BIH arrhythmia database and the obtained results show a competitive detection rate of over 99.7%.

Vision-based Vehicle Detection Using HOG and OS Fuzzy-ELM (HOG와 OS 퍼지-ELM를 이용한 비전 기반 차량 검출 시스템)

  • Yoon, Changyong;Lee, Heejin
    • Journal of the Korean Institute of Intelligent Systems
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    • 제25권6호
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    • pp.621-628
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    • 2015
  • This paper describes an algorithm for detecting vehicles detection in real time. The proposed algorithm has the technique based on computer vision and image processing. In real, complex environment such as one with road traffic, many algorithms have great difficulty such as low detection rate and increasing computational time due to complex backgrounds and rapid changes. To overcome this problem in this paper, the proposed algorithm consists of the following methods. First, to effectively separate the candidate regions, we use vertical and horizontal edge information, and shadow values from input image sequences. Second, we extracts features by using HOG from the selected candidate regions. Finally, this paper uses the OS fuzzy-ELM based on SLFN to classify the extracted features. The experimental results show that the proposed method perform well for detecting vehicles and improves the accuracy and the computational time of detecting.

Input Device of Non Touch Screen Using Hand Region Skeleton Model (손 영역 스켈레톤 모델을 이용한 비접촉 스크린 입력 장치)

  • Seo, Hyo-Dong;Kim, Hyo-Jin;Joo, Young-Hoon;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.1906-1907
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    • 2011
  • 본 논문에서는 손 영역 스켈레톤 모델을 이용한 비접촉식 스크린 입력 장치를 제안한다. 제안하는 방법은 HCbCr 컬러 모델을 생성한 후 손 후보 영역을 추출하고, 손 영역을 추출하기 위해 레이블링 기법을 사용한다. 손 이외의 피부를 제거하기 위해 손 크기 이하의 객체는 필터링을 거친 후 최종적인 손 영역을 추출한다. 손 영역의 특징점은 무게 중심법과 굴곡 기법을 이용하여 추출한다. 특징점을 연결하여 손의 스켈레톤 모델을 생성하고 각 손가락에 터치 이벤트를 부여한다. 손가락의 구부러진 각도를 이용하여 터치 동작을 인식 및 실행하게 된다.

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Spatial Join Processing using Representative Point Filter (대표점 필터를 이용한 공간조인 처리)

  • Joo, In-Hak;Ko, Myeong-Cheol;Choy, Yoon-Chul;Koh, Kyun
    • Journal of KIISE:Databases
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    • 제27권4호
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    • pp.637-650
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    • 2000
  • 공간조인은 지리정보시스템에서 가장 중요한 연산 중의 하나이다. 본 논문에서는 공간조인 처리를 위하여 여과-정제 방법을 사용할 때 여과단계에서의 효과를 높이기 위하여 점 기반 approximation인 Representative Point (RP) 필터를 제안하였다. RP 필터는 실객체에서 선택된 몇 개의 점들로 구성된다. 이 점들을 객체의 근사치로 사용함으로써 공간조인의 여과단계에서 후보객체의 수를 줄이며, 따라서 공간조인의 수행 성능을 높일 수 있다. 또한 RP 필터의 여러 종류들을 제안하였으며 그 종류들의 성질과 성능을 비교분석 하였다. RP필터는 공간조인을 위한 기존의 approximation들에 비하여 생성 및 우지 비용이 매우 적으며 더 높은 필터율을 가진다. 또한 RP 필터는 기존의 approximation들과 달리 선객체에 대하여도 정의될 수 있기 때문에, 다각형 객체끼리의 공간조인 뿐만 아니라 다각형 객체와 선 객체간의 공간조인에도 적용할 수 있다.

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