• Title/Summary/Keyword: detection methods

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Change Detection using KOMPSAT EOC Images

  • Jeong Jae-joon;Kim Younsoo
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.518-521
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    • 2004
  • Change detection is one of the common research topics in remote sensing. In general, global change detection methods using image difference method, etc, are used in low resolution images and local change detection methods using floating windows, etc, are used in high resolution images. But, these methods have disadvantages in practical use. If changed area images are automatically produced, these images will be used in public area such as regional planning, regional development managements. In this research, we developed new change detection method applicable KOMPSAT EOC images. This method automatically produces subset images in changed area.

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An Edge Detection Algorithm using Modified Mask in AWGN Environment (AWGN 환경에서 변형된 마스크를 이용한 에지 검출 알고리즘)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.892-894
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    • 2013
  • Edge has been utilized in various application fields with development of technique of digital image processing. In conventional edge detection methods, there are some methods using mask including Sobel, Prewitt, Roberts and Laplacian operator. Those methods are that implement is simple but generates errors of edge detection in images added AWGN(additive white Gaussian noise). Therefore, to compensate the defect of those methods, in this paper, an edge detection algorithm using modified mask is proposed, and it showed superior edge detection property in AWGN.

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An Architecture Design of Distributed Internet Worm Detection System for Fast Response

  • Lim, Jung-Muk;Han, Young-Ju;Chung, Tai-Myoung
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.161-164
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    • 2005
  • As the power of influence of the Internet grows steadily, attacks against the Internet can cause enormous monetary damages nowadays. A worm can not only replicate itself like a virus but also propagate itself across the Internet. So it infects vulnerable hosts in the Internet and then downgrades the overall performance of the Internet or makes the Internet not to work. To response this, worm detection and prevention technologies are developed. The worm detection technologies are classified into two categories, host based detection and network based detection. Host based detection methods are a method which checks the files that worms make, a method which checks the integrity of the file systems and so on. Network based detection methods are a misuse detection method which compares traffic payloads with worm signatures and anomaly detection methods which check inbound/outbound scan rates, ICMP host/port unreachable message rates, and TCP RST packet rates. However, single detection methods like the aforementioned can't response worms' attacks effectively because worms attack the Internet in the distributed fashion. In this paper, we propose a design of distributed worm detection system to overcome the inefficiency. Existing distributed network intrusion detection systems cooperate with each other only with their own information. Unlike this, in our proposed system, a worm detection system on a network in which worms select targets and a worm detection system on a network in which worms propagate themselves cooperate with each other with the direction-aware information in terms of worm's lifecycle. The direction-aware information includes the moving direction of worms and the service port attacked by worms. In this way, we can not only reduce false positive rate of the system but also prevent worms from propagating themselves across the Internet through dispersing the confirmed worm signature.

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Fast Hough Transform Using Multi-statistical Methods (다중 통계기법을 이용한 고속 하프변환)

  • Cho, Bo-Ho;Jung, Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.19 no.10
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    • pp.1747-1758
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    • 2016
  • In this paper, we propose a new fast Hough transform to improve the processing time and line detection of Hough transform that is widely used in various vision systems. First, for the fast processing time, we reduce the number of features by using multi-statistical methods and also reduce the dimension of angle through six separate directions. Next, for improving the line detection, we effectively detect the lines of various directions by designing the line detection method which detects line in proportion to the number of features in six separate directions. The proposed method was evaluated with previous methods and obtained the excellent results. The processing time was improved in about 20% to 50% and line detection was performed better in various directions than conventional methods with experimental images.

Detection of Irradiated Korean Wheat Flour by Viscosity and Pulsed Photostimulated Luminescence (PPSL) Methods

  • Yi, Sang-Duk;Chang, Kyu-Seob;Oh, Man-Jin
    • Preventive Nutrition and Food Science
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    • v.10 no.2
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    • pp.140-144
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    • 2005
  • This study was carried out to establish methods for irradiation detection of irradiation in Korean wheat flour by pulsed photostimulated luminescence (PPSL) and viscometric methods. The photon counts of the irradiated Korean wheat flour measured by PPSL immediately after irradiation increased with increasing irradiation dose. The photon counts in the irradiated Korean wheat flour almost disappeared with lapse of time after storage in normal room conditions, but irradiation detection was still possible after 6 months in darkroom conditions. All irradiated samples indicated a decrease in viscosity with increasing stirring speeds (rpm) and irradiation doses. Irradiation at 1 kGy significantly decreased the viscosity. Consequently, these results suggest that the detection of irradiated Korean wheat powder is possible by both viscometric and PPSL methods.

Hybrid copy-move-forgery detection algorithm fusing keypoint-based and block-based approaches (특징점 기반 방식과 블록 기반 방식을 융합한 효율적인 CMF 위조 검출 방법)

  • Park, Chun-Su
    • Journal of Internet Computing and Services
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    • v.19 no.4
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    • pp.7-13
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    • 2018
  • The methods for detecting copy move frogery (CMF) are divided into two categories, block-based methods and keypoint-based methods. Block-based methods have a high computational cost because a large number of blocks should be examined for CMF detection. In addition, the forgery detection may fail if a tampered region undergoes geometric transformation. On the contrary, keypoint-based methods can overcome the disadvantages of the block-based approach, but it can not detect a tampered region if the CMF forgery occurs in the low entropy region of the image. Therefore, in this paper, we propose a method to detect CMF forgery in all areas of image by combining keypoint-based and block-based methods. The proposed method first performs keypoint-based CMF detection on the entire image. Then, the areas for which the forgery check is not performed are selected and the block-based CMF detection is performed for them. Therefore, the proposed CMF detection method makes it possible to detect CMF forgery occurring in all areas of the image. Experimental results show that the proposed method achieves better forgery detection performance than conventional methods.

An Edge Detection Algorithm for Impulse Noise Images (임펄스 잡음 영상을 위한 에지 검출 알고리즘)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.770-772
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    • 2013
  • Edges on the images are widely used in preprocessing in various areas including recognition and detection of the object. As generally known edge detection methods, there is a method using mask and these methods are Sobel, Prewitt, Roberts, Laplacian operator and etc. Implementation of these existing edge detection methods is simple. However, when processing the impulse noise added images, the properties of edge detection is not sufficient. Accordingly, in order to compensate for the weakness of existing edge detection methods and to detect strong edges on the images which were damaged by impulse noise, the edge detection algorithm using transformed mask was proposed in this paper.

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A Study on Edge Detection using Standard Deviation of Local Masks (국부 마스크의 표준편차를 이용한 에지 검출에 관한 연구)

  • Lee, Chang-Young;An, Young-Joo;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.782-784
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    • 2013
  • As digital image processing technologies are developing, edges are being utilized in various areas. In the existing edge detection methods, there are mask methods which utilize Sobel, Prewitt, Roberts, Laplacian operator etc. To realize these existing edge detection methods is simple. But, in case that AWGN(additive white Gaussian noise) added images are processed, edge detection characteristics are slightly insufficient. Therefore, the edge detection algorithm using the standard deviation of local mask was suggested in this paper to compensate for the drawbacks in the existing detection methods and the suggested algorithm in AWGN environments showed excellent edge detection characteristics.

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Rapid Detection Methods for Agro-Food Safety

  • Kim, Gi-Young
    • 한국환경농학회:학술대회논문집
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    • 2009.07a
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    • pp.157-168
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    • 2009
  • Frequent outbreaks of foodborne illness have been increasing the awareness of agro-food safety. Conventional methods for pathogen detection and identification are labor.intensive and take days to complete. The increasing use of rapid food safety testing is receiving more and more attention. The major reason for this trend is that the food industry requires quick and accurate results. The rapid detection of contaminants in food is critical for ensuring the safety of consumers. Recent advances in technology make detection and identification faster, more sensitive and more specific than traditional method. In this paper, technology trends and recent developments in rapid methods for agro-food safety are discussed.

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Determination of Aflatoxins Using High-Performance Liquid Chromatography and Fluorescence or UV Absorbence Detection (HPLC에 의한 aflatoxin 분석법에 관한 연구 형광 및 자외선 흡광 검출의 비교)

  • 김종규;강회양;민경진
    • Journal of Environmental Health Sciences
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    • v.22 no.1
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    • pp.36-44
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    • 1996
  • A comparison was made of two detection methods(UV absorbence detection and fluorescence detection with pre-column derivatization, with trifluoroacetic acid) coupled with HPLC for the simultaneous determination of aflatoxin $B_1, B_2, G_1$ and $G_2$. A good separation of the four aflatoxins was achieved on a reversed-phase $C_{18}$ column (30 cm x 3.9 mm) with methanol-acetonitrile-water(20+20+60) for absorbence detection or acetonitrile-water(25+75) for fluorescence detection at the flow rate of 1.0 ml/min. The calibration graphs were linear over the ranges 100 ppb-1 ppm for $B_1/G_1$ and 30~300 ppb for $B_2/G_1$ with absorbence detection, and 1~500 ppb for $B_1/G_1$ and 0.3~150 ppb for $B_2/G_2$ with fluorescence detection. The correlation coefficients were greater than 0.94 and 0.99 for absorbance detection and for fluorescence detection, respectively. The detection limit was 100 ng for $B_1/G_1$ and 30 ng for $B_2/G_2$ with absorbence detection, and 1 ng for $B_1/G_1$ and 0.3 ng for $B_2/G_2$ with fluorescence detection. Recovery rates of aflatoxin $B_1, B_2, G_1$ and $G_2$ added to yeast-extract sucrose broth medium were 66.6%, 59.4%, 67.5% and 59.2%, respectively, for absorbence detection and 82.9%, 71.5%, 80.0% and 69.3%, respectively, for fluorescence detection. The four aflatoxins in culture medium were quantitatively detected by the two methods. The aflatoxins in the rice sample were not detected the absorbence detection method, but were below 10 ppb using the fluorescence detection method. Analysis of aflatoxins by both the absorbence and fluorescence methods coupled with HPLC showed acceptable linearity and good recovery. The absorbence detection was less timeconsuming and safer for treatment. The fluorescence detection was more elective and sensitive though elevated $B_1$ and $G_1$ contents were determined from the TFA-induced conversion of $B_1$ to $B_{2a}$ and $G_1$ to $G_{2a}$.

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