• 제목/요약/키워드: Detection,

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IS-95역방향 링크에서 단일 적분 및 이중 적분 검색 방식의 성능 분석 (Performance evaluation of the single-dwell and double-dwell detection schemes in the IS-95 reverse link)

  • 강법주;박형래;손정영;강창언
    • 한국통신학회논문지
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    • 제21권2호
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    • pp.383-393
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    • 1996
  • This paper considers the evaluation of the ecquistion performance for an accesschannel preamble based on a random access procedure of direct sequence code division multiple access(DS/CDMA) reverse link. The parallel acquistion technique that employs the single-well detection scheme and the multiple-dwell(double-dwell) detection scheme is mentioned. The acquisition performance for two detection schemes is compared in therms of the acquisition probability and the acquisition time. The parallel acquisition is done by a bank of N parallel I/Q noncoherent correlators. Expressions on the detection, false alarm, and miss probabilities of the single-dwell and multiple-dwell(double-well) detection schemes are derived for multiple H$_{1}$ cells and multipath Rayleight fading channel. comparing the single-dwell detection scheme with the multiple-dwell(double-dwell) detection scheme in the case of employing the parallel acquisition technique in the reverse link,the numerical results show that the single-dwell detection scheme deomonstrates a better performance.

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실제적인 Time-Selective Fading Channels에서의 Orthogonal Space-Time Block Codes의 Detection Scheme (A robust detection scheme of OSTBCs with channel estimation errors over time-selective fading channels)

  • 유동헌;이재홍
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.17-18
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    • 2006
  • In this paper, we propose a robust detection scheme of OSTBCs with channel estimation errors over time-selective fading channels. Channel estimation errors are inevitable over time-selective fading channels and even small channel estimation errors dramatically degrade the performance of space-time block coding schemes. Therefore, it is desired to investigate the effect of channel estimation errors on the performance of the proposed detection scheme compared with the existing detection scheme. The proposed detection scheme minimizes noise enhancement and impact of channel estimation errors which occur in an existing detection scheme. It is shown by simulations that the proposed detection scheme performs better than the existing detection scheme over time-selective fading channels.

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TFM 방식에서 Trellis 검파의 성능 분석 (Performance Analysis of Trellis Detection in the TFM System)

  • 정의성;조형래;홍대식;강창언
    • 전자공학회논문지A
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    • 제29A권7호
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    • pp.1-9
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    • 1992
  • In this thesis, the trellis detection scheme is proposed to improve the error performance of the noncoherent detection in the TFM system. Trellis detection takes advantage of the trellis property of TFM-encoded signals. The trellis property is created by giving correlations among adjacent TFM-encoded signals at the transmitter. The performance of the trellis detection scheme is analyzed by means of the Bernoulli trials with the average symbol error probability, and is compared to that of the bit-by-bit detection scheme. As a result,when the SNR is below 20 dB in the Rayleigh fading and AWGN channel, the trellis detection is inferior to the bit-by-bit detections. But when SNR is above 20 dB, the trellis detection is superior to the bit-by-bit detection, and its performance enhancement is better as the SNR increases.

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경계선 검출 성능에 영향을 주는 변수 변화에 따른 경계선 검출 알고리듬 성능의 정량적인 평가 방법 (A Method for Quantitative Performance Evaluation of Edge Detection Algorithms Depending on Chosen Parameters that Influence the Performance of Edge Detection)

  • 양희성;김유호;한정현;이은석;이준호
    • 한국통신학회논문지
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    • 제25권6B호
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    • pp.993-1001
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    • 2000
  • This research features a method that quantitatively evaluates the performance of edge detection algorithms. Contrary to conventional methods that evaluate the performance of edge detection as a function of the amount of noise added to he input image, the proposed method is capable of assessing the performance of edge detection algorithms based on chosen parameters that influence the performance of edge detection. We have proposed a quantitative measure, called average performance index, that compares the average performance of different edge detection algorithms. We have applied the method to the commonly used edge detectors, Sobel, LOG(Laplacian of Gaussian), and Canny edge detectors for noisy images that contain straight line edges and curved line edges. Two kinds of noises i.e, Gaussian and impulse noises, are used. Experimental results show that our method of quantitatively evaluating the performance of edge detection algorithms can facilitate the selection of the optimal dge detection algorithm for a given task.

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블록체인을 적용한 사설 클라우드 기반 침입시도탐지 (A Probe Detection based on Private Cloud using BlockChain)

  • 이세열
    • 디지털산업정보학회논문지
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    • 제14권2호
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    • pp.11-17
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    • 2018
  • IDS/IPS and networked computer systems are playing an increasingly important role in our society. They have been the targets of a malicious attacks that actually turn into intrusions. That is why computer security has become an important concern for network administrators. Recently, various Detection/Prevention System schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems is useful for existing intrusion patterns on standard-only systems. Therefore, probe detection of private clouds using BlockChain has become a major security protection technology to detection potential attacks. In addition, BlockChain and Probe detection need to take into account the relationship between the various factors. We should develop a new probe detection technology that uses BlockChain to fine new pattern detection probes in cloud service security in the end. In this paper, we propose a probe detection using Fuzzy Cognitive Map(FCM) and Self Adaptive Module(SAM) based on service security using BlockChain technology.

영상검지기법을 활용한 끼어들기 위반차량 검지 방법에 관한 연구 (A Study on the Detecting Method of Intercept Violation Vehicles Using an Image Detection Techniques)

  • 김완기;류부형
    • 한국안전학회지
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    • 제23권6호
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    • pp.164-170
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    • 2008
  • This research was verified detection way of intercept vehicles and performance evaluation after system installation using image detector as detection way of ground installation. By image recognition algorithm was on the trace of moving orbit of violation vehicles for detection way of intercept vehicles. When moving orbit is located special site, utilized geometric image calibration and DC-notch filter. These are cognitive system of license plate by making signal. Then, Bright Evidence Detection and Dark Evidence Detection were applied to after mixing. It is applied to way of Backward tracking for detection way of intercept vehicles. After the field evaluation of developed system, it should be analyzed the more high than recognition rate of minimum standards 80%. It should rise in the estimation of the site applicability is highly from now.

Robust Real-time Intrusion Detection System

  • Kim, Byung-Joo;Kim, Il-Kon
    • Journal of Information Processing Systems
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    • 제1권1호
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    • pp.9-13
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    • 2005
  • Computer security has become a critical issue with the rapid development of business and other transaction systems over the Internet. The application of artificial intelligence, machine learning and data mining techniques to intrusion detection systems has been increasing recently. But most research is focused on improving the classification performance of a classifier. Selecting important features from input data leads to simplification of the problem, and faster and more accurate detection rates. Thus selecting important features is an important issue in intrusion detection. Another issue in intrusion detection is that most of the intrusion detection systems are performed by off-line and it is not a suitable method for a real-time intrusion detection system. In this paper, we develop the real-time intrusion detection system, which combines an on-line feature extraction method with the Least Squares Support Vector Machine classifier. Applying the proposed system to KDD CUP 99 data, experimental results show that it has a remarkable feature extraction and classification performance compared to existing off-line intrusion detection systems.

A data corruption detection scheme based on ciphertexts in cloud environment

  • Guo, Sixu;He, Shen;Su, Li;Zhang, Xinyue;Geng, Huizheng;Sun, Yang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권9호
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    • pp.3384-3400
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    • 2021
  • With the advent of the data era, people pay much more attention to data corruption. Aiming at the problem that the majority of existing schemes do not support corruption detection of ciphertext data stored in cloud environment, this paper proposes a data corruption detection scheme based on ciphertexts in cloud environment (DCDC). The scheme is based on the anomaly detection method of Gaussian model. Combined with related statistics knowledge and cryptography knowledge, the encrypted detection index for data corruption and corruption detection threshold for each type of data are constructed in the scheme according to the data labels; moreover, the detection token for data corruption is generated for the data to be detected according to the data labels, and the corruption detection of ciphertext data in cloud storage is realized through corresponding tokens. Security analysis shows that the algorithms in the scheme are semantically secure. Efficiency analysis and simulation results reveal that the scheme shows low computational cost and good application prospect.

RAVIP: Real-Time AI Vision Platform for Heterogeneous Multi-Channel Video Stream

  • Lee, Jeonghun;Hwang, Kwang-il
    • Journal of Information Processing Systems
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    • 제17권2호
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    • pp.227-241
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    • 2021
  • Object detection techniques based on deep learning such as YOLO have high detection performance and precision in a single channel video stream. In order to expand to multiple channel object detection in real-time, however, high-performance hardware is required. In this paper, we propose a novel back-end server framework, a real-time AI vision platform (RAVIP), which can extend the object detection function from single channel to simultaneous multi-channels, which can work well even in low-end server hardware. RAVIP assembles appropriate component modules from the RODEM (real-time object detection module) Base to create per-channel instances for each channel, enabling efficient parallelization of object detection instances on limited hardware resources through continuous monitoring with respect to resource utilization. Through practical experiments, RAVIP shows that it is possible to optimize CPU, GPU, and memory utilization while performing object detection service in a multi-channel situation. In addition, it has been proven that RAVIP can provide object detection services with 25 FPS for all 16 channels at the same time.

CNN 알고리즘을 이용한 인공지지체의 3D프린터 출력 시 실시간 출력 불량 탐지 시스템에 관한 연구 (A Study on Real-Time Defect Detection System Using CNN Algorithm During Scaffold 3D Printing)

  • 이송연;허용정
    • 반도체디스플레이기술학회지
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    • 제20권3호
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    • pp.125-130
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    • 2021
  • Scaffold is used to produce bio sensor. Scaffold is required high dimensional accuracy. 3D printer is used to manufacture scaffold. 3D printer can't detect defect during printing. Defect detection is very important in scaffold printing. Real-time defect detection is very necessary on industry. In this paper, we proposed the method for real-time scaffold defect detection. Real-time defect detection model is produced using CNN(Convolution Neural Network) algorithm. Performance of the proposed model has been verified through evaluation. Real-time defect detection system are manufactured on hardware. Experiments were conducted to detect scaffold defects in real-time. As result of verification, the defect detection system detected scaffold defect well in real-time.