• Title/Summary/Keyword: waveform detection

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A study on the adaptive detection of EEG waveforms (EEG파형의 실시간 적응적 감지에 관한 연구)

  • 심신호;장태규;양원영
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.877-882
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    • 1993
  • An adaptive EEG waveform detection is presented. The method is based on a layered process model. The model allows the bilateral information exchange across the layers. The criteria for the waveform detection and epoch-wise classification can be adapted according to the higher layer context information embedded in a wider range of adjacent signals. The designed system is experimentally tested to show the adaptive operation of the waveform detection.

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Electric Leakage Point Detection System of Underground Power Cable Using Half-period Modulated Transmission Waveform and Earth Electric Potential Measurement (반주기 변조된 송신파형과 대지전위 측정을 이용한 지중 케이블 누전 고장점 탐지 시스템)

  • Jeon, Jeong Chay;Yoo, Jae-Geun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.12
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    • pp.2113-2118
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    • 2016
  • The precise detection of electric leakage point of underground power cable is very important to reduce cost and time of maintenance and prevent electric shock accident through expedite repair of electric leakage point. This paper proposes a electric leakage point detection system underground power cable using of half-period modulated transmission waveform and earth electric potential measurement. The developed system is composed of transmitter to generate the wanted pulse waveform, receiver to measure and display earth electric potential by the transmitted pulse in electric leakage point and PC Software program to display of GPS coordinate on detection cable line. The performance of the electric leakage point detection system was tested in the constructed underground cable leakage detection test bed. The test results on signal generation voltage precision of signal transmitter, mean detection earth voltage, mean detection leakage current and electric leakage point detection error showed the developed system can be used in electric leakage point detection underground power cable.

Waveform Detection Algorithm based on the Search of Distinctive Line-Segments (검색에 기초한 파형 검출 알고리듬)

  • 박승훈;장태규
    • Journal of Biomedical Engineering Research
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    • v.14 no.3
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    • pp.265-272
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    • 1993
  • We present a new waveform detection method, based on the search of distinctive line-segments. The method is based on the basic assumption that the waveform morphology of biological signals is readily characterized by a sequence of the distinctive line-segments and their structural features. In this method, the distinctive line-segments are first searched for, and a structural feature analysis is performed an the distinctive line-segments found. Experiments of detecting epileptic spikes were carried out to evaluate the detection per formance of the method. Two subjects were used for training and tuning the algorithm and four subjects for testing the method. The results were obtained on two different performance indices, detection ratio and the number of false detections per minute.

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Waveform Decomposition of Airborne Bathymetric LiDAR by Estimating Potential Peaks (잠재적 피크 추정을 통한 항공수심라이다 웨이브폼 분해)

  • Kim, Hyejin;Lee, Jaebin;Kim, Yongil;Wie, Gwangjae
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1709-1718
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    • 2021
  • The waveform data of the Airborne Bathymetric LiDAR (ABL; LiDAR: Light Detection And Ranging) system provides data with improved accuracy, resolution, and reliability compared to the discrete-return data, and increases the user's control over data processing. Furthermore, we are able to extract additional information about the return signal. Waveform decomposition is a technique that separates each echo from the received waveform with a mixture of water surface and seabed reflections, waterbody backscattering, and various noises. In this study, a new waveform decomposition technique based on a Gaussian model was developed to improve the point extraction performance from the ABL waveform data. In the existing waveform decomposition techniques, the number of decomposed echoes and decomposition performance depend on the peak detection results because they use waveform peaks as initial values. However, in the study, we improved the approximation accuracy of the decomposition model by adding the estimated potential peak candidates to the initial peaks. As a result of an experiment using waveform data obtained from the East Coast from the Seahawk system, the precision of the decomposition model was improved by about 37% based on evaluating RMSE compared to the Gaussian decomposition method.

Comparative study for height accuracy of Full waveform LiDAR data (Full waveform LiDAR의 높이 정확도 비교 분석)

  • Ryu, Joong-Hi;Lee, Jae-Hwan;Koh, Seung-Bum;Kim, Back-Seok;Seo, Hae-Soo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.3
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    • pp.257-263
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    • 2011
  • There are many previous researches such as verification of accuracy, application, and change detection of discrete return LiDAR data, but no researches for full waveform LiDAR data. In this study, we selected the forest area and urban area as case study areas and compared the height accuracy of full waveform LiDAR data with field surveying data. As a result, we got an RMSE of 3.lcm in urban area, 4.7cm in forest area, and it is verified that height accuracy of full waveform LiDAR is high. We think that it is very usefull in aerial photogrammetry.

Implementation of an LFM-FSK Transceiver for Automotive Radar

  • Yoo, HyunGi;Park, MyoungYeol;Kim, YoungSu;Ahn, SangChul;Bien, Franklin
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.4
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    • pp.258-264
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    • 2015
  • The first 77 GHz transceiver that applies a heterodyne structure-based linear frequency modulation-frequency shift keying (LFM-FSK) front-end module (FEM) is presented. An LFM-FSK waveform generator is proposed for the transceiver design to avoid ghost target detection in a multi-target environment. This FEM consists of three parts: a frequency synthesizer, a 77 GHz up/down converter, and a baseband block. The purpose of the FEM is to make an appropriate beat frequency, which will be the key to solving problems in the digital signal processor (DSP). This paper mainly focuses on the most challenging tasks, including generating and conveying the correct transmission waveform in the 77 GHz frequency band to the DSP. A synthesizer test confirmed that the developed module for the signal generator of the LFM-FSK can produce an adequate transmission signal. Additionally, a loop back test confirmed that the output frequency of this module works well. This development will contribute to future progress in integrating a radar module for multi-target detection. By using the LFM-FSK waveform method, this radar transceiver is expected to provide multi-target detection, in contrast to the existing method.

Unusual Waveform Detection Algorithm in Arrhythmia ECG Signal (부정맥 심전도 신호에서 특이 파형 검출)

  • Park, Kil-Houm;Kim, Jin-Sub;Ryu, Chunha;Choi, Byung-Jae;Kim, Jungjoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.23 no.4
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    • pp.292-297
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    • 2013
  • In this paper, unusual waveform detection algorithm based on Refractory Period in arrhythmia ECG signal is proposed. Most of arrhythmia ECG signals consist of unusual waveforms with average 10% rate. Thus tremendous benefit can be obtained in terms of time and cost by providing unusual waveform samples reduced more than 90% to medical staffs who have to monitor and analyze for a long time. The proposed algorithm detects the R-peak using the features of R wave and variable refractory period. For the detected R-peak, unusual waveforms are found using means and standard deviation of electric potential and kurtosis of the R-peaks which are not included in unusual waveform. The proposed algorithm was applied to all records of the MIT-BIH arrhythmia database and showed more than average 90% of compression ratio.

EEG WAVEFORM DETECTION BASED ON THE SEARCH OF DISTINCTIVE LINE-SEGMENTS (특징적인 직선요소들의 검색에 기초한 EEG 파형 검출)

  • Park, Seung-Hun;Chang, Tae-Kyu
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.121-122
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    • 1992
  • We present a new EEG waveform detection method, based on the search of distinctive line-segments. The method is based on the assumption that EEG waveform morphology is characterized by a sequence of its distinctive line-segments and their structural features. In this method, the distinctive line segments are first searched for, and the structural feature analysis is performed on the found line-segment sequence. Experiments of detecting epileptic spikes are performed on four different subjects.

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A Speech Waveform Forgery Detection Algorithm Based on Frequency Distribution Analysis (음성 주파수 분포 분석을 통한 편집 의심 지점 검출 방법)

  • Heo, Hee-Soo;So, Byung-Min;Yang, IL-Ho;Yu, Ha-Jin
    • Phonetics and Speech Sciences
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    • v.7 no.4
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    • pp.35-40
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    • 2015
  • We propose a speech waveform forgery detection algorithm based on the flatness of frequency distribution. We devise a new measure of flatness which emphasizes the local change of the frequency distribution. Our measure calculates the sum of the differences between the energies of neighboring frequency bands. We compare the proposed measure with conventional flatness measures using a set of a large amount of test sounds. We also compare- the proposed method with conventional detection algorithms based on spectral distances. The results show that the proposed method gives lower equal error rate for the test set compared to the conventional methods.

Real-time Detection of spindle Waveforms Based on the Local Spectrum of EEG (국부스펙트럼에 근거한 뇌파 스핀들 파형의 실시간 감지에 관한 연구)

  • Shim, Shin-H.;Chang, Tae-G.;Yang, Won-Y.
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.281-283
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    • 1993
  • A new method of EEG spindle waveform detection i s presented. The method combines the signal conditioning in the time-domin and the analysis of local spectrum in the frequency-domain. Fast computation methods, utilizing some effective approximations, are also suggested for the desist and implementation of the filter as well as for the computation of the local spectrum. The presented approach is especially useful for the real-time implementation of the waveform detection system under a general purpose microcomputer environment. The overall detection system is implemented and tested on-line with the total 24 hour data of selected four subjects. The result show the average agreement of 86.7% with the visually inspected result.

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