• Title/Summary/Keyword: Filtering and detection

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A Study of Edge Detection for Auto Focus of Infrared Camera

  • Park, Hee-Duk
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.1
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    • pp.25-32
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    • 2018
  • In this paper, we propose an edge detection algorithm for auto focus of infrared camera. We designed and implemented the edge detection of infrared image by using a spatial filter on FPGA. The infrared camera should be designed to minimize the image processing time and usage of hardware resource because these days surveillance systems should have the fast response and be low size, weight and power. we applied the $3{\times}3$ mask filter which has an advantage of minimizing the usage of memory and the propagation delay to process filtering. When we applied Laplacian filter to extract contour data from an image, not only edge components but also noise components of the image were extracted by the filter. These noise components make it difficult to determine the focus state. Also a bad pixel of infrared detector causes a problem in detecting the edge components. So we propose an adaptive edge detection filter that is a method to extract only edge components except noise components of an image by analyzing a variance of pixel data in $3{\times}3$ memory area. And we can detect the bad pixel and replace it with neighboring normal pixel value when we store a pixel in $3{\times}3$ memory area for filtering calculation. The experimental result proves that the proposed method is effective to implement the edge detection for auto focus in infrared camera.

An Automated Technique for Detecting Axon Structure in Time-Lapse Neural Image Sequence (시간 경과 신경계 영상 시퀀스에서의 축삭돌기 추출 기법)

  • Kim, Nak Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.3
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    • pp.251-258
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    • 2014
  • The purpose of the neural image analysis is to trace the velocities and the directions of moving mitochondria migrating through axons. This paper proposes an automated technique for detecting axon structure. Previously, the detection process has been carried out using a partially automated technique combined with some human intervention. In our algorithm, a consolidated image is built by taking the maximum intensity value on the all image frames at each pixel Axon detection is performed through vessel enhancement filtering followed by a peak detection procedure. In order to remove errors contained in ridge points, a filtering process is devised using a local reliability measure. Experiments have been performed using real neural image sequences and ground truth data extracted manually. It has been turned out that the proposed algorithm results in high detection rate and precision.

Movie Recommendation Algorithm Using Social Network Analysis to Alleviate Cold-Start Problem

  • Xinchang, Khamphaphone;Vilakone, Phonexay;Park, Doo-Soon
    • Journal of Information Processing Systems
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    • v.15 no.3
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    • pp.616-631
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    • 2019
  • With the rapid increase of information on the World Wide Web, finding useful information on the internet has become a major problem. The recommendation system helps users make decisions in complex data areas where the amount of data available is large. There are many methods that have been proposed in the recommender system. Collaborative filtering is a popular method widely used in the recommendation system. However, collaborative filtering methods still have some problems, namely cold-start problem. In this paper, we propose a movie recommendation system by using social network analysis and collaborative filtering to solve this problem associated with collaborative filtering methods. We applied personal propensity of users such as age, gender, and occupation to make relationship matrix between users, and the relationship matrix is applied to cluster user by using community detection based on edge betweenness centrality. Then the recommended system will suggest movies which were previously interested by users in the group to new users. We show shown that the proposed method is a very efficient method using mean absolute error.

Audio Watermarking Using Independent Component Analysis

  • Seok, Jong-Won
    • Journal of information and communication convergence engineering
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    • v.10 no.2
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    • pp.175-180
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    • 2012
  • This paper presents a blind watermark detection scheme for an additive watermark embedding model. The proposed estimation-correlation-based watermark detector first estimates the embedded watermark by exploiting non-Gaussian of the real-world audio signal and the mutual independence between the host-signal and the embedded watermark and then a correlation-based detector is used to determine the presence or the absence of the watermark. For watermark estimation, blind source separation (BSS) based on independent component analysis (ICA) is used. Low watermark-to-signal ratio (WSR) is one of the limitations of blind detection with the additive embedding model. The proposed detector uses two-stage processing to improve the WSR at the blind detector; the first stage removes the audio spectrum from the watermarked audio signal using linear predictive (LP) filtering and the second stage uses the resulting residue from the LP filtering stage to estimate the embedded watermark using BSS based on ICA. Simulation results show that the proposed detector performs significantly better than existing estimation-correlationbased detection schemes.

Development of On-Line Patial Discharge Detector for Power (운전 중인 전력기기의 부분방전 측정장치 개발에 관하여)

  • 김광화;선종호;김우성;이종구;이준모;강창원
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.733-739
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    • 2000
  • This paper is described the development of on-line partial discharge detector for high voltage apparatus. This detector consists of acoustic and high frequency current sensors, amplifier part, A/D converter part, data communication part and computer. The contents of paper are characteristics of units and digital signal processing for reducing noise in partial discharge detection. We seek methods to do good digital signal processing for detection of partial discharge. We apply digital filtering methods to the elect Tic signal and a cross con-elation to the acoustic signal. This paper shows the characteristics of these filtering method and cross con-elation in partial discharge detection.

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A Study on DDoS(Distributed Denial of Service) Attack Detection Model Based on Statistical (통계 기반 분산서비스거부(DDoS)공격 탐지 모델에 관한 연구)

  • Kook, Yoon-Ju;Kim, Yong-Ho;Kim, Jeom-Goo;Kim, Kiu-Nam
    • Convergence Security Journal
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    • v.9 no.2
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    • pp.41-48
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    • 2009
  • Distributed denial of service attack detection for more development and research is underway. The method of using statistical techniques, the normal packets and abnormal packets to identify efficient. In this paper several statistical techniques, using a mix of various offers a way to detect the attack. To verify the effectiveness of the proposed technique, it set packet filtering on router and the proposed DDoS attacks detection method on a Linux router. In result, the proposed technique was detect various attacks and provide normal service mostly.

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Damage Detection on Thin-walled Structures Utilizing Laser Scanning and Standing Waves (레이저 스캐닝 및 정상파를 이용한 평판 구조물의 손상탐지)

  • Kang, Se Hyeok;Jeon, Jun Young;Kim, Du Hwan;Park, Gyuhae;Kang, To;Han, Soon Woo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.5
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    • pp.401-407
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    • 2017
  • This paper describes wavenumber filtering for damage detection using single-frequency standing wave excitation and laser scanning sensing. An embedded piezoelectric sensor generates ultrasonic standing waves, and the responses are measured using a laser Doppler vibrometer and mirror tilting device. After scanning, newly developed damage detection techniques based on wavenumber filtering are applied to the full standing wave field. To demonstrate the performance of the proposed techniques, several experiments were performed on composite plates with delamination and aluminum plates with corrosion damage. The results demonstrated that the developed techniques could be applied to various structures to localize the damage, with the potential to improve the damage detection capability at a high interrogation speed.

Simplified Module Based Self-collision Detection for Humanoid Robots (간략화 된 모듈 기반의 휴머노이드 로봇을 위한 자기충돌 탐지)

  • Kwak, Hwan-Joo;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.240-241
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    • 2008
  • We are presenting the efficient and robust simplified module based self-collision detection of humanoid robot simulator. For safe and reliable operations of humanoid robot, the self-collision detection is essential and extremely important. The main methods of self-collision detection are inverse X-Y-Z fixed angles and module distance filtering (MDF). According to experiments on the humanoid robot simulator with the self-collision detection, we could have a confidence about the efficiency of the self-collision.

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Optical Design and Construction of Narrow Band Eliminating Spatial Filter for On-line Defect Detection (온라인 결함계측용 협대역 제거형 공간필터의 최적설계 및 제작)

  • 전승환
    • Journal of the Korean Institute of Navigation
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    • v.22 no.4
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    • pp.59-67
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    • 1998
  • A quick and automatic detection with no harm to the goods is very important task for improving quality control, process control and labour reduction. In real fields of industry, defect detection is mostly accomplished by skillful workers. A narrow band eliminating spatial filter having characteristics of removing the specified spatial frequency is developed by the author, and it is proved that the filter has an excellent ability for on-line and real time detection of surface defect. By the way,. this spatial filter shows a ripple phenominum in filtering characteristics. So, it is necessary to remove the ripple component for the improvement of filter gain, moreover efficiency of defect detection. The spatial filtering method has a remarkable feature which means that it is able to set up weighting function for its own sake, and which can to obtain the best signal relating to the purpose of the measurement. Hence, having an eye on such feature, theoretical analysis is carried out at first for optimal design of narrow band eliminating spatial filter, and secondly, on the basis of above results spatial filter is manufactured, and finally advanced effectiveness of spatial filter is evaluated experimentally.

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Noise Elimination and Edge Detection based on Fuzzy Logic (퍼지 논리를 이용한 잡음 제거 및 에지 검출)

  • 이혜정;정성태;정석태
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.3
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    • pp.506-512
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    • 2003
  • The edge detection has been so far under a lot of studies on its methods, as a very important part of image recognition. Never the less the correct detection of the edge has been yet a difficult problem because of the various scopes of detection according to the applied field. One of those problems to be solved is the edge detection in images with noise. This paper presents an efficient method which removes noise and detect edge in the same framework based on fuzzy logic. The method consists of two steps. First, an efficient filtering is applied to eliminate the noise from original image. The filtering is performed by utilizing fuzzy MIN-MAX operator in three directions such as vertical, horizontal and diagonal angle of 3${\times}$3 mask. Second, edges are detected by using extended fuzzy Shanon Function.