• Title/Summary/Keyword: Period Detection

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Intelligent Image Analysis System for Preventing Safety Hazards in Dangerous Working Area (작업안전 위험상황 대응을 위한 지능형 영상분석 시스템 구축에 관한 연구)

  • Jang, Hyun Song
    • Journal of the Korea Safety Management & Science
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    • v.17 no.2
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    • pp.47-54
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    • 2015
  • To prevent safety hazards in dangerous working area, we have proposed an intelligent image analysis system. Six common patterns of safety violations of workers' are defined and its motion detection algorithms are developed for alarm to CCTV monitoring system. Developed algorithms are implemented at 195 dangerous areas such as chemical and gas treated room. The results of violated motion detection ratio by developed system shows 94.95% of true positive cases, and 0.21% of false positive cases from all 587,645 event cases in one month implementation period. In the period, it is observed that the number of safety rule violations and the following accidents are decreased.

Design of a CT Saturation Detection Technique with the Countermeasure for a Spike Signal

  • Kang, Yong-Cheol;Yun, Jae-Sung
    • KIEE International Transactions on Power Engineering
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    • v.3A no.2
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    • pp.85-92
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    • 2003
  • When a current transformer (CT) is saturated, the wave-shape of the secondary current is distorted and contains points of inflection, which correspond to the start or end of each saturation period. Discontinuity in the first-difference function of the current arises at points of inflection, where the second and third differences convert into pulses that can be used to detect saturation. This paper describes the design and evaluation of a CT saturation detection technique using the third-difference function and includes the countermeasure for a spike signal. Test results clearly demonstrate that the algorithm successfully detects the start and end of each saturation period irrespective of the remanent flux and magnetization inductance in the saturated region. This paper concludes by describing the results of hardware implementation of the algorithm using a DSP.

Evaluation of Application of Possibility of Visual Surveillance System for Cow Heat Detection

  • Park, Heesu;Roy, Pantu Kumar;Noh, Youngju;Park, Hyuk;Lee, Joongho;Shin, Sangtae;Cho, Jongki
    • Journal of Embryo Transfer
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    • v.31 no.2
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    • pp.137-143
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    • 2016
  • This study was conducted to evaluate a visual surveillance system. The advancement of recording technology and network service make it easy to record and transfer the videos. Moreover, progressed recognition technology help to make a distinction each other. Cows show distinguishing behaviors during their estrus period. The mounting is one of the behaviors. The result was different depending on the breed of the cows and the size of the farm. In the case of Korean native cattle, the estrus detection rate was 71.15%, however, dairy cows, the estrus detection rate was 39.38%. At the farms having below 6 modules, the estrus detection rate was 87.41%. On the other hand, at the farms having over 6 modules, the estrus detection rate was 77.78%. With the proper progress, the visual surveillance system can be used to detect heat detection.

Automated Detection Technique for Suspected Copyright Infringement Sites

  • Jeong, Hae Seon;Kwak, Jin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.12
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    • pp.4889-4908
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    • 2020
  • With the advances in Information Technology (IT), users can download or stream copyrighted works, such as videos, music, and webtoons, at their convenience. Thus, the frequency of use of copyrighted works has increased. Consequently, the number of unauthorized copies and sharing of copyrighted works has also increased. Monitoring is being conducted on sites suspected of conducting copyright infringement activities to reduce copyright holders' damage due to unauthorized sharing of copyrighted works. However, suspected copyright infringement sites respond by changing their domains or blocking access requests. Although research has been conducted for improving the effectiveness of suspected copyright infringement site detection by defining suspected copyright infringement sites' response techniques as a lifecycle step, there is a paucity of studies on automation techniques for lifecycle detection. This has reduced the accuracy of lifecycle step detection on suspected copyright infringement sites, which change domains and lifecycle steps in a short period of time. Thus, in this paper, an automated detection technique for suspected copyright infringement sites is proposed for efficient detection and response to suspected copyright infringement sites. Using our proposed technique, the response to each lifecycle step can be effectively conducted by automatically detecting the lifecycle step.

A Study on Pitch Detection using Cochlear Model on Cochannel Speech (청각 모델을 이용한 Cochannel 음성에서의 피치 추출에 관한 연구)

  • Sin, Dae-Gyu;Sin, Jung-In;Lee, Jae-Hyeok;Han, Du-Jin;Park, Sang-Hui
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.6
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    • pp.330-333
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    • 2000
  • In this paper, a new pitch estimation method is proposed using the Robinson cochlear model. This estimation method is useful in noisy environments and especially very efficient under cochannel in which two speaker voices exist at the same time. For the one speaker speech, the pitch can be extracted from just the neurogram of the Robinson cochlear model. In this case, as the estimation is performed in time domain, the exact pitch period can be detected though the pitch period is various. But in noisy and cochannel cases, the neurogram has many spurious peaks, so we use the autocorrelators in the neurogram to manifest the period. It the autocorrelators are used for the all delays, the large amount of calculations is necessary. Due to this defect, we propose that the autocorrelators are used for the part of the delays on which energy is concentrated. First of all, the proposed algorithm is applied to the one speaker speech, and later to the cochannel speech. And then the results are compared with the autocorrelation pitch detection method.

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Optimal Spectrum Sensing Framework based on Estimated Miss Detection Probability for Aggregated Data Slots in Cognitive Radio Networks (무선 인지 네트워크에서 군집형 데이터 슬롯의 미검출 확률 추정에 기반한 최적 스펙트럼 센싱 구조)

  • Wu, Hyuk;Lee, Dong-Jun
    • Journal of Advanced Navigation Technology
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    • v.17 no.5
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    • pp.506-515
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    • 2013
  • In cognitive radio networks, several research works typically address the framework which consists of a spectrum sensing period and a data transmission period. When the frame period is short, there is the problem that the throughput of secondary users decrease. In this paper, aggregated data slot structure is considered to increase the throughput of secondary users. Chapman-Kolmogorov equation is used for the modeling of the transmission probability of primary users and formulation of an optimization problem to maximize the throughput of secondary users. Solution of the optimization problem results in the optimal spectrum sensing time, the length of data slot and the number of data slots governed by a spectrum sensing.

Thermal Imaging Fire Detection Algorithm with Minimal False Detection

  • Jeong, Soo-Young;Kim, Won-Ho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.5
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    • pp.2156-2170
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    • 2020
  • This paper presents a fire detection algorithm with a minimal false detection rate, intended for a thermal imaging surveillance environment, whose properties vary depending on temporal conditions of day or night and environmental changes. This algorithm was designed to minimize the false detection alarm rate while ensuring a high detection rate, as required in fire detection applications. It was necessary to reduce false fire detections due to non-flame elements occurring when existing fixed threshold-based fire detection methods were applied. To this end, adaptive flame thresholds that varied depending on the characteristics of input images, as well as the center of gravity of the heat-source and hot-source regions, were analyzed in an attempt to minimize such non-flame elements in the phase of selecting flame candidate blocks. Also, to remove any false detection elements caused by camera shaking, one of the most frequently raised issues at outdoor sites, preliminary decision thresholds were adaptively set to the motion pixel ratio of input images to maximize the accuracy of the preliminary decision. Finally, in addition to the preliminary decision results, the texture correlation and intensity of the flame candidate blocks were averaged for a specific period of time and tested for their conformity with the fire decision conditions before making the final decision. To verify the fire detection performance of the proposed algorithm, a total of ten test videos were subjected to computer simulation. As a result, the fire detection accuracy of the proposed algorithm was determined to be 94.24%, with minimum false detection, demonstrating its improved performance and practicality compared to previous fixed threshold-based algorithms.

Urban Environment change detection through landscape indices derived from Landsat TM data

  • Iisaka, Joji
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.696-701
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    • 2002
  • This paper describes some results of change detection in Tokyo metropolitan area, Japan , using the Landsat TM data, and methods to quantify the ground cover classes. The changes are analyzed using the measures of not only conventional spectral classes but also a set of landscape indices to describe spatial properties of ground cove types using fractal dimension of objects, entropy in the specific windows defining the neighbors of focusing locations. In order eliminate the seasonal radiometric effects on TM data, an automated class labeling method is also attempted. Urban areas are also delineated automatically by defining the boundaries of the urban area. These procedures for urban change detection were implemented by the unified image computing methods proposed by the author, they can be automated in coherent and systematic ways, and it is anticipated to automate the whole procedures. The results of this analysis suggest that Tokyo metropolitan area was extended to the suburban areas along the new transportation networks and the high density area of Tokyo were also very much extended during the period between 1985 and 1995.

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Economic Evaluation of Early Detection System for Warranty Issues (품질보증 이슈 조기감지 시스템의 경제성 평가)

  • Jung, Sung-Hwan
    • Journal of Korean Society for Quality Management
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    • v.40 no.1
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    • pp.39-48
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    • 2012
  • An early detection system for warranty issues periodically collects customers' claim data and automatically reports alarms about emerging issues based on statistical algorithms. It helps companies to reduce an issue definition time and save the handling cost of warranty claims. This paper provides an evaluation framework to validate the economic effect of an early detection system project. For this purpose, we present economical index of a project with explicit formulas such as ROI(return on investment), PP(payback period), NPV(net present value), PI(profitability index) and IRR(internal rate of return) and analyze the sensitivities of the index according to the variation of project input parameters. The proposed analysis framework is expected to be used for evaluating economic values of various system integration projects.

Flattening Techniques for Pitch Detection (피치 검출을 위한 스펙트럼 평탄화 기법)

  • 김종국;조왕래;배명진
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.381-384
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    • 2002
  • In speech signal processing, it Is very important to detect the pitch exactly in speech recognition, synthesis and analysis. but, it is very difficult to pitch detection from speech signal because of formant and transition amplitude affect. therefore, in this paper, we proposed a pitch detection using the spectrum flattening techniques. Spectrum flattening is to eliminate the formant and transition amplitude affect. In time domain, positive center clipping is process in order to emphasize pitch period with a glottal component of removed vocal tract characteristic. And rough formant envelope is computed through peak-fitting spectrum of original speech signal in frequency domain. As a results, well get the flattened harmonics waveform with the algebra difference between spectrum of original speech signal and smoothed formant envelope. After all, we obtain residual signal which is removed vocal tract element The performance was compared with LPC and Cepstrum, ACF 0wing to this algorithm, we have obtained the pitch information improved the accuracy of pitch detection and gross error rate is reduced in voice speech region and in transition region of changing the phoneme.

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