• Title/Summary/Keyword: Sequential detection

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Detection Schemes Based on Local Optimality and Sequential Criterion: 1. Threshold Analysis (국소 최적성과 순차 기준을 바탕으로 한 검파 기법: 1. 문턱값 분석)

  • Choi Sang Won;Oh Jongho;Kwon Hyoungmoon;Yoon Seokho;Bae Jinsoo;Song Iickho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.6C
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    • pp.532-540
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    • 2005
  • In this paper, a sequential detection scheme is proposed as a combination of a novel weak-signal and a locally optimum(LO) detection schemes. In Part 1, we propose a novel sequential detection scheme for weak signals and show some interesting threshold properties and examples. In Part 2, the performance of the proposed sequential detection scheme is compared with that of the fixed sample size(FSS) test, sequential probability ratio test (SPRT), and truncated sequential probability ratio test(TSPRT).

Detection Schemes Based on Local Optimality and Sequential Criterion: 2. Performance Analysis (국소 최적성과 순차 기준을 바탕으로 한 검파 기법: 2. 성능 분석)

  • Choi Sang Won;Kang Hyun Gu;Lee Jumi;Park So Ryoung;Kim Sun Yong;Song Iickho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10C
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    • pp.1027-1035
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    • 2005
  • In this paper, the performance of the sequential detection scheme proposed in Part 1 is compared with that of the fixed sample size (FSS) test, sequential probability ratio test (SPRT), and truncated sequential probability ratio test (TSPRT). The proposed sequential detection scheme requires less complexity and, in most cases, smaller sample size than the SPRT. It is also observed that the proposed sequential detection scheme has always lower complexity and smaller sample size than the FSS test and TSPRT.

TFT-LCD Defect Blob Detection based on Sequential Defect Detection Method (순차적 결함 검출 방법에 기반한 TFT-LCD 결함 영역 검출)

  • Lee, Eunyoung;Park, Kil-Houm
    • Journal of Korea Society of Industrial Information Systems
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    • v.20 no.2
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    • pp.73-83
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    • 2015
  • This paper proposes a TFT-LCD defect blob detection algorithm using the sequential defect detection method. First, for every pixel, a defect possibility is determined by the intensity difference and the defect candidates are detected according to the sequential defect detection method. For detected candidate pixels, the defect probability that indicates a potential included in the defect according to the each step. By applying the morphological operation, blobs are comprised of the detected candidates and the defect blobs are detected using the defect possibility of blobs. The validity of the proposed method was demonstrated a simulated image and also then it was tested a real TFT-LCD image. By the experimental results, the proposed method is very effective in TFT-LCD detect detection.

QR Decomposition Based Sequential Belief Propagation Detection Scheme for MIMO Systems (MIMO 시스템을 위한 QR 분해 기반 순차적 신뢰 전파 검출 기법)

  • Park, Sangjoon;Choi, Sooyong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.9
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    • pp.1725-1727
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    • 2015
  • In this letter, a QR decomposition based sequential BP detection scheme is proposed for MIMO systems. The proposed scheme performs the sequential updates from the observation node having the smallest degree among all the observation nodes. Our simulation results verify that the proposed scheme achieves an improved error performance with a significantly accelerated detection convergence speed compared to the conventional schemes.

Scene Change Detection with Sequential Access Method in Compressed MPEG Videos (순차접근법을 이용한 MPEG 압축영역에서의 장면전환점 검출)

  • Ahn, Eui-Sub;Song, Hyun-Soo;Lee, Jae-Dong;Kim, Sung-Un
    • The KIPS Transactions:PartB
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    • v.11B no.3
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    • pp.353-360
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    • 2004
  • The study on scene change detection in the compressed MPEG videos has been done by various approaches. However, most of these approacher accomplished scene change detection by carrying out decoding processes and then by comparing pixels with pixels. This approach it not suitable for real time applications owing to much computing time of decoding processes. Recently, the study on scene change detection algorithms using only information of compressed domain is becoming Increasingly important. In this paper, we propose a sequential access method as an efficient scene change detection algorithm in the compressed domain. According to the type of pictures in the compressed MPEG video streams (divided in I-blocks and each I-block into P-blocks), the proposed algorithm provides effective scene change detection by applying sequential access and block by block mechanism. The proposed sequential access method provides fast and accurate detection operation by reducing checking procedures of unnecessary pictures due to molt of operations in compressed domain and checking by block units. Also, this approach uses optimal algorithm to provide fast and accurate detection operation.

Dwell Time Optimization of Alert-Confirm Detection for Active Phased Array Radars

  • Kim, Eun Hee;Park, JoonYong
    • Journal of electromagnetic engineering and science
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    • v.19 no.2
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    • pp.107-114
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    • 2019
  • Alert-confirm detection is a highly efficient method to improve phased array radar search performance. It comprises sequential detection in two steps: alert detection, in which a target is detected at a low detection threshold, and confirm detection, which is triggered by alert detection with a longer dwell time to minimize false alarms. This paper provides a design method for applying the alert-confirm detection to multifunctional radars. We find optimum dwell times and false alarm probabilities for each alert detection and confirm detection under the dual constraints of total false alarm probability and maximum allowable dwell time per position. These optimum values are expressed as a function of the mean new target appearance rate. The proposed alert-confirm detection increases the maximum detection range even with a shorter frame time than that of uniform scanning.

Cooperative Spectrum Sensing Via Sequential Detection: A Method to Reduce the Sensing Time

  • Thanh, Truc Tran;Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.12 no.3
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    • pp.196-202
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    • 2012
  • Spectrum sensing is one of the most important functions in cognitive radio systems. In this paper, we focus on reducing the sensing time in a cooperative spectrum sensing paradigm. In the proposed scheme, a sequential detection technique is employed to provide a robust and quick detection system. Each of the secondary users measures the log-likelihood probability of the received signals and then sequentially reports to the base station. Here, the maximum ratio combining (MRC) technique is employed to reduce the average sample number (ASN) in order to reduce the sensing time. This proposed scheme is analyzed and simulated to illustrate the performance in comparison with the other given methods. Analysis and simulation are provided to validate the proposed method.

Sequential Pattern Mining for Intrusion Detection System with Feature Selection on Big Data

  • Fidalcastro, A;Baburaj, E
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.10
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    • pp.5023-5038
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    • 2017
  • Big data is an emerging technology which deals with wide range of data sets with sizes beyond the ability to work with software tools which is commonly used for processing of data. When we consider a huge network, we have to process a large amount of network information generated, which consists of both normal and abnormal activity logs in large volume of multi-dimensional data. Intrusion Detection System (IDS) is required to monitor the network and to detect the malicious nodes and activities in the network. Massive amount of data makes it difficult to detect threats and attacks. Sequential Pattern mining may be used to identify the patterns of malicious activities which have been an emerging popular trend due to the consideration of quantities, profits and time orders of item. Here we propose a sequential pattern mining algorithm with fuzzy logic feature selection and fuzzy weighted support for huge volumes of network logs to be implemented in Apache Hadoop YARN, which solves the problem of speed and time constraints. Fuzzy logic feature selection selects important features from the feature set. Fuzzy weighted supports provide weights to the inputs and avoid multiple scans. In our simulation we use the attack log from NS-2 MANET environment and compare the proposed algorithm with the state-of-the-art sequential Pattern Mining algorithm, SPADE and Support Vector Machine with Hadoop environment.

SPRT-based Collaboration Construction for Malware Detection in IoT

  • Jun-Won Ho
    • International journal of advanced smart convergence
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    • v.12 no.1
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    • pp.64-69
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    • 2023
  • We devise a collaboration construction method based on the SPRT (Sequential Probability Ratio Test) for malware detection in IoT. In our method, high-end IoT nodes having capable of detecting malware and generating malware signatures harness the SPRT to give a reward of malware signatures to low-end IoT nodes providing useful data for malware detection in IoT. We evaluate our proposed method through simulation. Our simulation results indicate that the number of malware signatures provided for collaboration is varied in accordance with the threshold for fraction of useful data.

An Algorithm to Reduce the Number of Nodes in Active Spectrum Sensing Via Cooperative Sequential Detection

  • Truc, Tran Thanh;Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.12 no.2
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    • pp.148-154
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    • 2012
  • In this paper, we propose an algorithm to conserve resources of the common control channel in a cognitive radio network by rejecting the redundant users using cooperative spectrum sensing. The proposed scheme is investigated under the paradigm of active spectrum sensing and a sequential detection technique. The algorithm is based on the J-divergence between the hypotheses of non primary user operation and the otherwise case. We select the most significant eigenvalues, which primarily affect the global statistical test. For the case where interference is from a secondary system transmission, a match filter is first employed to remove the degradation, and then the proposed algorithm is employed to remove the cooperative sensing nodes. Numerical results are provided and compared with conventional cases in order to validate the performance of the proposed algorithm.