• 제목/요약/키워드: Sign detection

검색결과 198건 처리시간 0.027초

Application of Multiple Threshold Values for Accuracy Improvement of an Automated Binary Change Detection Model

  • Yu, Byeong-Hyeok;Chi, Kwang-Hoon
    • 대한원격탐사학회지
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    • 제25권3호
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    • pp.271-285
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    • 2009
  • Multi-temporal satellite imagery can be changed into a transform image that emphasizes the changed area only through the application of various change detection techniques. From the transform image, an automated change detection model calculates the optimal threshold value for classifying the changed and unchanged areas. However, the model can cause undesirable results when the histogram of the transform image is unbalanced. This is because the model uses a single threshold value in which the sign is either positive or negative and its value is constant (e.g. -1, 1), regardless of the imbalance between changed pixels. This paper proposes an advanced method that can improve accuracy by applying separate threshold values according to the increased or decreased range of the changed pixels. It applies multiple threshold values based on the cumulative producer's and user's accuracies in the automated binary change detection model, and the analyst can automatically extract more accurate optimal threshold values. Multi-temporal IKONOS satellite imagery for the Daejeon area was used to test the proposed method. A total of 16 transformation results were applied to the two study sites, and optimal threshold values were determined using accuracy assessment curves. The experiment showed that the accuracy of most transform images is improved by applying multiple threshold values. The proposed method is expected to be used in various study fields, such as detection of illegal urban building, detection of the damaged area in a disaster, etc.

수화방송 모니터링을 위한 수화영역 검출 방법 연구 (A Study on sign-language object detection for sign language broadcasting monitoring)

  • 최지훈;안충현;서정일
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2018년도 추계학술대회
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    • pp.99-100
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    • 2018
  • 청각장애인을 위한 수화방송 서비스는 지상파 기준으로 100% 제공하는 자막방송 서비스와 달리 콘텐츠 제작비용과 시스템 운영비용 등으로 인해 5% 수준의 편성에 그치고 있다. 이러한 편성 비율조차도 명확한 편성기준과 검증기준이 없어서 실제 청각장애인이 실제 체감하는 수준은 훨씬 낮은 상황이다. 본 논문에서는 지상파 방송사업자의 장애인방송 편성비율을 검증하기 위해서 방송프로그램 안내정보와 방송 시그널링 정보를 기반으로 채널별로 방송스트림을 수집 및 관리하는 장애인방송 모니터링 서버를 활용하여 수화방송 모니터링 기술 고도화를 위한 자동화된 수화영역 검출 방법을 제안한다. 마지막으로, 자동화된 수화영역 검출 방법을 활용한 수화방송 모니터링 결과를 보여준다.

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가중치 함수를 이용한 위상 검출 알고리즘과 위상 추적 루프의 설계 (An algorithm for pahse detection using weighting function and the design of a phase tracking loop)

  • 이명환
    • 한국통신학회논문지
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    • 제23권9A호
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    • pp.2197-2210
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    • 1998
  • In the grand alliance (GA) HDTV receiver, a coherent detection is empolyed for coherent demodulation of vestigial side-band (VSB) signal by using frequency and phaselocked loop(FPLL) operating on the pilot carrier. Additional phase tracking loop (PTL) employed to track out phase noise that has not been removed by the FPLL in theGA system. In this paper, we propose an algorithm for phase detection which utilizes a weighting function. The simplest implementation of the proposed algorithm using te sign of the Q channel component can be tractable by imposing a phase detection gain to the loop gain. It is obserbed that the propsoed algorithm has a robust characteristic against the performance of the digital filters used for Q channel estimation. A second goal of this paper is to introduce a gain control algorithm for the PTL in order to provide an effective implementation of the proposed phase detection algorithm. And we design the PTL through the realization of the simplified digital filter for H/W reduction. The proposed algorithms and the designed PTL are evaluated by computer simulation. In spite of using the simplified H/W structure, simulation results show that the proposed algorithms outperform the coventional PTL algorithms in the phase detection and tracking performance.

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신호처리(II)-Random Process의 detection 및 estimation Karhunen.Loeve의 전개, 한 서상의 SVD (Signal Processing(II)-Detection and Estimation of Random Process, Karhunen Lo$\grave{e}$ve Expansion, SVD of an Image))

  • 안수길
    • 대한전자공학회논문지
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    • 제17권1호
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    • pp.1-9
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    • 1980
  • 신호처리와 analysis를 위한 여러 기초적인 기술이 소개되었다. 이들은 먼저 불확정성순리의 개입에 의하여 특히 교환불가능한 operator 들이 작용한 결과의 등호는 tolerance가 있을 수 있음과 random process 처리방법과 manmum entropy estimate적인 ,사고방식을 통하여 재래식 확정론적 사고방식으로부터의 이탈을 길잡았다. 마지막으로 검출, 추정 및 함수추정의 여러 기법과 covariance functron의 posltive semi-definite-ness 그리고 Karhunen-Loeve 전개, 한 화상의 SVD 등이 설명됐다.

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Single-molecule Detection of Fluorescence Resonance Energy Transfer Using Confocal Microscopy

  • Kim, Sung-Hyun;Choi, Don-Seong;Kim, Do-Seok
    • Journal of the Optical Society of Korea
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    • 제12권2호
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    • pp.107-111
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    • 2008
  • We demonstrated single-molecule fluorescence resonance energy transfer (FRET) from single donor-acceptor dye pair attached to a DNA with a setup based on a confocal microscope. Singlestrand DNAs were immobilized on a glass surface with suitable inter-dye distance. Energy transfer efficiency between the donor and the acceptor dyes attached to the DNA was measured with different lengths of DNA. Photobleaching of single dye molecule was observed and used as a sign of single-molecule detection. We could achieve high enough signal-to-noise ratio to detect the fluorescence from a single-molecule, which allows real-time observation of the distance change between single dye pairs in nanometer scale.

IR-UWB 레이더를 이용한 비접촉 실시간 심박탐지 (A Non-contact Realtime Heart Rate Estimation Using IR-UWB Radar)

  • 변상선
    • 대한임베디드공학회논문지
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    • 제14권3호
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    • pp.123-131
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    • 2019
  • In recent years, a non-contact respiration and heart rates monitoring via IR-UWB radar has been paid much attention to in various applications - patient monitoring, occupancy detection, survivor exploring in disaster area, etc. In this paper, we address a novel approach of real time heart rate estimation using IR-UWB radar. We apply sine fitting and peak detection method for estimating respiration rate and heart rate, respectively. We also deploy two techniques to mitigate the error caused by wrong estimation of respiration rate: a moving average filter and finding the frequency of the highest occurrence. Experimental results show that the algorithm can estimate heart rate in real time when respiration rate is presumed to be estimated accurately.

Proposing a New Approach for Detecting Malware Based on the Event Analysis Technique

  • Vu Ngoc Son
    • International Journal of Computer Science & Network Security
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    • 제23권12호
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    • pp.107-114
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    • 2023
  • The attack technique by the malware distribution form is a dangerous, difficult to detect and prevent attack method. Current malware detection studies and proposals are often based on two main methods: using sign sets and analyzing abnormal behaviors using machine learning or deep learning techniques. This paper will propose a method to detect malware on Endpoints based on Event IDs using deep learning. Event IDs are behaviors of malware tracked and collected on Endpoints' operating system kernel. The malware detection proposal based on Event IDs is a new research approach that has not been studied and proposed much. To achieve this purpose, this paper proposes to combine different data mining methods and deep learning algorithms. The data mining process is presented in detail in section 2 of the paper.

인터넷 환경에서의 비정상행위 공격 탐지를 위한 위협관리 시스템 (Threat Management System for Anomaly Intrusion Detection in Internet Environment)

  • 김효남
    • 한국컴퓨터정보학회논문지
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    • 제11권5호
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    • pp.157-164
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    • 2006
  • 최근에는 대부분의 인터넷 공격은 악성코드(Malware)에 의한 잘 알려지지 않은 제로데이 공격 형태가 주류를 이루고 있으며, 이미 알려진 공격유형들에 대해서 탐지하는 오용탐지 기술로는 이러한 공격에 대응하기가 어려운 실정이다. 또한, 다양한 공격 패턴들이 인터넷상에 나타나고 있기 때문에 기존의 정보 보호 기술로는 한계에 다다르게 되었고, 웹기반 서비스가 보편화됨에 따라 인터넷상에 노출된 웹 서비스가 주공격 대상이 되고 있다. 본 논문은 인터넷상의 트래픽 유형을 분류하고, 각 유형에 따른 이상 징후를 탐지하고 분석할 수 있는 비정상행위공격 탐지기술(Anomaly Intrusion Detection Technologies)을 포함하고 있는 위협관리 시스템(Threat Management System)을 제안한다.

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The Detection Distance of Colored Target using Various Automotive Headlamps

  • Kim, Jung-Yong;Lee, Ho-Sang;Min, Seung-Nam;Lee, Min-Ho
    • 대한인간공학회지
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    • 제31권3호
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    • pp.421-426
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    • 2012
  • As headlamp technology advances, newly developed various headlamps were introduced in the market. The objective of this study is to quantitatively analyze the detection distance of the recently developed LED headlamps and existing headlamps, complying with specific technical standard. Background: The detection distance of headlamps is very important to prevent automobile accident at night time. The studies of detection distance of LED, Halogen and HID headlamp have been conducted, but no study has shown the detection distance of pedestrian target with various colors (Black, White, Blue). Method: The experiment of detection distance was conducted with 30 people, which divide into 2 groups as 15 men and 15 women. Automatic transferable target on the rail was manufactured in order to reduce the error of study's result, and ANOVA also conducted to analyze the main effect with sign color, sex and headlamp classified by detection distance. In addition, the luminance by average detection distance was measured as well. Results: The detection distance of headlamps was HID > LED > Halogen. The luminance measure of LED headlamp was lower than HID and Halogen headlamps. Conclusion: The headlamp performs a very significant role for safety at night time but it needs to be improved through assessment of visual characteristics. Also, it needs to be suggested the need of test method for dynamic detection distance concerning technical development is suggested.

자기연상 학습 신경망과 부호 입력 변수를 이용한 종합주가지수 "왼쪽어깨" 패턴 검출 (“Left Shoulder”Detection in Korea Composite Stock Price Index Using an Auto-Associative Neural Network and Sign Variables)

  • 백진우;조성준
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2000년도 추계학술대회 및 정기총회
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    • pp.29-32
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    • 2000
  • We proposed a neural network based “left shoulder”detector. The auto-associative neural network was trained with the “left shoulder”patterns obtained from the Korea Composite Stock Price Index, and then tested out-of-sample with a reasonably good result. A hypothetical investment strategy based on the detector achieved a return of 132% in comparison with 39% return from a buy and hold strategy

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