• 제목/요약/키워드: Sequential Detection

검색결과 260건 처리시간 0.021초

Malware Detector Classification Based on the SPRT in IoT

  • Jun-Won Ho
    • International journal of advanced smart convergence
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    • 제12권1호
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    • pp.59-63
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    • 2023
  • We create a malware detector classification method with using the Sequential Probability Ratio Test (SPRT) in IoT. More specifically, we adapt the SPRT to classify malware detectors into two categories of basic and advanced in line with malware detection capability. We perform evaluation of our scheme through simulation. Our simulation results show that the number of advanced detectors is changed in line with threshold for fraction of advanced malware information, which is used to judge advanced detectors in the SPRT.

동기화된 부호 분할 다원 접속 채널을 위한 ML 최적 다중 사용자 검출기의 간단한 계산 알고리즘 (A simple computational algorithm of ML optimum multiuser detector for synchronous code division multiple access channels)

  • 권형욱;최태영;오성근
    • 전자공학회논문지A
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    • 제33A권5호
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    • pp.1-9
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    • 1996
  • In this paper, we propose an efficient computational algorithm that can reduce significantly the computational complexity of the ML optimum multiuser detector known as the most excellent detector in synchronous code division multiple access channels. The proposed detector uses the sequential detection algorithm based on the alternating maximization appraoch to obtain the ML estimates. As initial estimates for this sequential algorithm, we can use the estimated values obtained by the conventional single-user detector, the linear decorrelating multiuser detector, or the decorrelating decision-feedback muliuser detector, the linear decorrelating multiuser detector, or the decorrelating decision-feedback multiuser detector. We have performed computer simulations in order to see the convergence behaviors and the detection performance of the propsoed algorithm in terms of initial algorithms and the number of users, and then to compare the computational complexity with that of the ML optimum multiuser detector. From the results, we have seen that the proposed alternating maximization detector has nearly equal detction performance with that of the ML optimum multiuser detctor in only a few iteration.

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동영상의 고속 장면분할을 위한 이진검색 알고리즘 (Bianry Searching Algorithm for HIgh Sped Scene Change Indexing of Moving Pictures)

  • 김성철;오일균;장종환
    • 한국정보처리학회논문지
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    • 제7권4호
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    • pp.1044-1049
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    • 2000
  • In detection of a scene change of the moving pictures which has massive information capacity, the temporal sampling method has faster searching speed than the sequential searching method for the whole moving pictures, yet employed searching algorithm and detection interval greatly affect searching time and searching precision. In this study, the whole moving pictures were primarily retrieved by the temporal sampling method. When there exist a scene change within the sampling interval, we suggested a fast searching algorithm using binary searching and derived an equation formula to determine optimal primary retrieval which can minimize computation, and showed the result of the experiment on MPEG moving pictures. The result of the experiment shows that the searching speed of the suggested algorithm is maximum 13 times faster than the one of he sequential searching method.

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적응예측기를 이용한 고장파악방법 (Failure Detection Using Adaptive Predictor)

  • 이연석;이장규
    • 대한전기학회논문지
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    • 제39권2호
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    • pp.210-217
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    • 1990
  • For the failure detection of dynamic systems, processing the residuals from the observer of the estimator is the most general method. A failure detection method which use an adaptive predictor to separate the effect of sensor failure from the additive noise in the residuals of a Kalman filter that is employed as an estimator of a dynamic system is addressed here. In the method, the property of the residuals of an optimal Kalman estimator is exploited. The simulation results of this method shows that the proposed method is superior to the sequential probability ratio test for a small failure magnitude.

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Alert-Confirm 탐지 방식의 설계 및 성능 분석에 관한 연구 (A Study on Design and Analysis of an Alert-Confirm Detection Method)

  • 김은희;오현수;민사원
    • 한국군사과학기술학회지
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    • 제27권2호
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    • pp.140-146
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    • 2024
  • Active electronically scanning antennas are faster and more flexible in beam-scheduling than mechanical antennas. Thus, they require an advanced resource management or detection methods to operate efficiently. In a surveillance radar performing periodic detection, alert-confirm detection is an excellent method to improve the cumulative detection probability by reducing the period while maintaining the detection probability. This paper proposes a design method for alert-confirm detection based on the parameters of the conventional design. We developed a simulator based on simulink@matworks and verified the result through Monte Carlo simulation.

Anomalous Event Detection in Traffic Video Based on Sequential Temporal Patterns of Spatial Interval Events

  • Ashok Kumar, P.M.;Vaidehi, V.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권1호
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    • pp.169-189
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    • 2015
  • Detection of anomalous events from video streams is a challenging problem in many video surveillance applications. One such application that has received significant attention from the computer vision community is traffic video surveillance. In this paper, a Lossy Count based Sequential Temporal Pattern mining approach (LC-STP) is proposed for detecting spatio-temporal abnormal events (such as a traffic violation at junction) from sequences of video streams. The proposed approach relies mainly on spatial abstractions of each object, mining frequent temporal patterns in a sequence of video frames to form a regular temporal pattern. In order to detect each object in every frame, the input video is first pre-processed by applying Gaussian Mixture Models. After the detection of foreground objects, the tracking is carried out using block motion estimation by the three-step search method. The primitive events of the object are represented by assigning spatial and temporal symbols corresponding to their location and time information. These primitive events are analyzed to form a temporal pattern in a sequence of video frames, representing temporal relation between various object's primitive events. This is repeated for each window of sequences, and the support for temporal sequence is obtained based on LC-STP to discover regular patterns of normal events. Events deviating from these patterns are identified as anomalies. Unlike the traditional frequent item set mining methods, the proposed method generates maximal frequent patterns without candidate generation. Furthermore, experimental results show that the proposed method performs well and can detect video anomalies in real traffic video data.

Sequential Fault Detection and Isolation for Redundant Inertial Sensor Systems with Uncertain Factors

  • Kim, Jeong-Yong;Yang, Cheol-Kwan;Shim, Duk-Sun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2594-2599
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    • 2003
  • We consider some problems of the Modified SPRT(Sequential Probability Ratio Test) method for fault detection and isolation of inertial redundant sensor systems and propose an Advanced SPRT method to solve the problems of the Modified SPRT method. One problem of the Modified SPRT method to apply to inertial sensor system comes from the effect of inertial sensor errors such as misalignment, scale factor error and sensor bias in the parity vector, which make the Modified SPRT method hard to be applicable. The other problem is due to the correlation of parity vector components which may induce false alarm. We use a two-stage Kalman filter to remove effects of the inertial sensor errors and propose the modified parity vector and the controlled parity vector which removes the effect of correlation of parity vector components. The Advanced SPRT method is derived form the modified parity vector and the controlled parity vector. Some simulation results are presented to show the usefulness of the Advanced SPRT method to redundant inertial sensor systems.

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연속 영상 분석에 의한 다중 차량 검출 방법의 연구 (A Study on The Detection of Multiple Vehicles Using Sequence Image Analysis)

  • 한상훈;이강호
    • 한국컴퓨터정보학회논문지
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    • 제8권2호
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    • pp.37-43
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    • 2003
  • 본 연구는 연속된 컬러 영상으로부터 전방의 차량과 차선을 검출하는 과정에서 연속 영상 분석을 통하여 다중 차량을 검출하는 방법을 제안한다. 하나의 프레임에서 차량 후보 영역의 검출은 그림자 특징과 에지 성분을 이용한다. 그리고, 다중 차량 영역을 검출하는 방법은 연속된 영상에 존재하는 차량 후보 영역들의 차량 추정값과(EOV)과 누적 유사도 함수(ASF)를 분석하여 차량일 가능성을 검사한다. 대부분의 연구 방법이 전방의 한 차량을 검출하는데 비해 본 연구에서는 여러 차량을 검출하는 방법을 제시하였으며, 교통량이 많고, 차선 변경이 자주 있는 경우에도 차량의 검출이 가능하도록 한다. 제안된 방식의 효과를 검증하기 위해 노트북 PC와 PC용 CCD 카메라로 도로에서의 영상을 촬영하고 차량 검출 알고리즘을 적용한 처리 시간, 정확도 및 차량검지 결과를 보인다.

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HCr과 적응적 임계화에 의한 고속 얼굴 검출 (Fast Face Detection in Video Using The HCr and Adaptive Thresholding Method)

  • 신승주;최석림
    • 대한전자공학회논문지SP
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    • 제41권6호
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    • pp.61-71
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    • 2004
  • 얼굴검출을 위한 다양한 연구가 행해지고 있으나 아직도 실시간성의 확보는 미진하다. 이에 본 연구는 연속영상에서 컬러와 움직임 정보를 이용한 실시간 얼굴검출 방법을 제안한다. 피부색 검출을 위한 컬러공간은 조명의 변화에 강인하고 피부색을 좁은 영역으로 정의할 수 있는 Hue와 Cr성분을 조합하여 재구성한 HCr을 사용한다. 배경참조영상 기반에서 밝기와 Cr 성분을 함께 사용하여 획득한 움직임 영역에서, HCr과 적응적 임계값을 이용해서 피부색 영역을 검출하고, 그 검출된 영역의 모양과 크기정보를 통해 얼굴 후보영역을 구한다. 이렇게 구해진 얼굴후보영역에서 G와 B성분의 차이, 밝기, Cr성분 값과 눈과 입의 위치 및 거리관계를 이용하여 눈과 입을 검출하여 얼굴을 확정한다. 실험결과 연속영상에서 실시간으로 얼굴을 검출 할 수 있었다.

Speed Sign Recognition Using Sequential Cascade AdaBoost Classifier with Color Features

  • Kwon, Oh-Seol
    • Journal of Multimedia Information System
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    • 제6권4호
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    • pp.185-190
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    • 2019
  • For future autonomous cars, it is necessary to recognize various surrounding environments such as lanes, traffic lights, and vehicles. This paper presents a method of speed sign recognition from a single image in automatic driving assistance systems. The detection step with the proposed method emphasizes the color attributes in modified YUV color space because speed sign area is affected by color. The proposed method is further improved by extracting the digits from the highlighted circle region. A sequential cascade AdaBoost classifier is then used in the recognition step for real-time processing. Experimental results show the performance of the proposed algorithm is superior to that of conventional algorithms for various speed signs and real-world conditions.