• Title/Summary/Keyword: Signal Evaluation

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Study on the IR Measurement Scheme and Requirement for Its Evaluation from a Naval ship Considering the Meteorological Conditions (기상 조건에 따른 함정의 적외선 방사신호 성능 평가시 고려요소 및 계측 방안 연구)

  • Gil, Tae-Jun;Cho, Yong-Jin
    • Journal of the Society of Naval Architects of Korea
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    • v.44 no.4
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    • pp.459-465
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    • 2007
  • This paper deals with the development of measuring methodology and the requirement for its evaluation of the infrared radiation from a naval ship to optical sensors, considering the Meteorological conditions. Factors required for measuring the apparent temperature and infrared radiation are identified and two methods are suggested based on the measuring instruments carried by ship or aircraft. and target operation in the Meteorological conditions is considered. This study describes some factors affecting the IR signature. required instruments to obtain the IR signal considering the naval ship.

The study of image quality evaluation and compression method using contourlet transform (정지 영상 화질 평가와 Contourlet 변환을 이용한 압축 방법에 관한 연구)

  • Jang, Jun-Ho;Kim, Young-Seop
    • Journal of the Semiconductor & Display Technology
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    • v.9 no.4
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    • pp.57-61
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    • 2010
  • The wavelet transform was adopted as the transform for JPEG2000. However, wavelet has weakness about smoothness along the contours and limited directional information. So we use to other transform, called contourlet transform in compression. Objective quality assessment methods currently used Peak signal to noise Ratio(PSNR). But that is not very well matched to perceived visual quality. So new image quality assessment is required. In this paper, we propose a new method for image compression based on the contourlet transform, which has been recently introduced. In addition we evaluated compression image quality using PSNR and SSIM. Finally contourlet transform has a good result about images with smooth contours and SSIM is good method for image evaluation compared to PSNR.

Wall Thickness Measurement of Respiratory Airway in CT Images: Signal Processing Aspects

  • Park, Sang-Joon;Kim, Jong-Hyo;Kim, Kwang-Gi;Lee, Sang-Ho
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.279-280
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    • 2007
  • Airway wall thickness is an important bio-marker for evaluation of pulmonary diseases such as stenosis, bronchiectasis. Nevertheless, an image-based analysis of the airway tree can provide precise and valuable airway size information, quantitative measurement of airway wall thickness in CT images involves various sources of error and uncertainty. So we have developed an accurate airway wall measurement technique for small airways with three-dimensional (3-D) approach. To illustrate performance of these techniques, we used airway phantom that consisted of 4 acryl tubes with various inner and outer diameters. Results show that evaluation of interpolation and deconvolution methods of airways in 3-D CT images, and significant improvement over the full-width-half-maximum method for measurement of not only location of the luminal and outer edge of the airway wall but airway wall thickness.

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Fault Analysis of Electric Equipment Using Vehicle Signal (차량신호를 이용한 주요 전장품의 고장 분석)

  • Han, Young-Jae;Kim, Ki-Hwan;Kim, Sang-Soo;Lee, Byoung-Seog;Jung, Sang-Hun;Cho, Byoung-Chan
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.1488-1494
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    • 2006
  • The most important thing to secure safety and reliability of railway vehicles is to verify performance characteristics of equipments, and related companies or research institutes had many efforts to verify performances and functions of equipments synthetically and efficiently. KHST(Korean High Speed Train) has been developed by KRRI(Korea Railroad Research Institute). An electric railway system is composed of high-tech subsystems, among which main electric equipment such as transformers and converter are critical components determining the performance of rolling stock. We developed a measurement system for on-line test and evaluation of performances of KHST. The measurement system is composed of software part and hardware part. Perfect interface between multi-users is possible. A new method to measure temperature was applied to the measurement system. By using the system, fault diagnosis and performance evaluation of electric equipment in Korean High Speed Train was conducted during test running.

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Review on RF Performance of Ultra Wide Band Device

  • Lee, Il-Kyoo;Kang, Bub-Joo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.2
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    • pp.34-39
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    • 2007
  • UWB(Ultra Wide Band) system for high speed and high accurate location has been studying actively. This paper presents the design and implementation of RF transceiver for DS-CDMA(Direct Sequence-Code Division Multiple Access) UWB device. Major components of RF transceiver such as Low Noise Amplifier(LNA) and Band Pass Filter(BPF) are designed and then fabricated to meet wideband characteristics. The RF transceiver was implemented by the use of the fabricated components and commercial devices after carrying out performance simulation. Through the performance evaluation of the UWB RF transceiver with W-CDMA signal, the approach of design, implementation and evaluation of RF transceiver which is available to DS-CDMA UWB system is verified.

A Study on KHST Monitoring System Using Vehicle Signal (차량신호를 이용한 고속열차 모니터링 시스템)

  • Han, Young-Jae;Kim, Ki-Hwan;Park, Choon-Soo;Kim, Sang-Soo
    • Proceedings of the KIEE Conference
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    • 2007.11a
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    • pp.206-207
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    • 2007
  • We developed a measurement system for on-line test and evaluation of performances of KHST. The measurement system is composed of software part and hardware part. Perfect interface between multi-users is possible. A new method to measure temperature was applied to the measurement system. By using the system, fault diagnosis and performance evaluation of electric equipment in Korean High Speed Train was conducted during test running.

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A Study on the Detecting Method of Intercept Violation Vehicles Using an Image Detection Techniques (영상검지기법을 활용한 끼어들기 위반차량 검지 방법에 관한 연구)

  • Kim, Wan-Ki;Ryu, Boo-Hyung
    • Journal of the Korean Society of Safety
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    • v.23 no.6
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    • pp.164-170
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    • 2008
  • This research was verified detection way of intercept vehicles and performance evaluation after system installation using image detector as detection way of ground installation. By image recognition algorithm was on the trace of moving orbit of violation vehicles for detection way of intercept vehicles. When moving orbit is located special site, utilized geometric image calibration and DC-notch filter. These are cognitive system of license plate by making signal. Then, Bright Evidence Detection and Dark Evidence Detection were applied to after mixing. It is applied to way of Backward tracking for detection way of intercept vehicles. After the field evaluation of developed system, it should be analyzed the more high than recognition rate of minimum standards 80%. It should rise in the estimation of the site applicability is highly from now.

A STOCHASTIC EVALUATION OF ACTUAL SOUND ENVIRONMENT BASED ON TWO TYPE INFORMATION PROCESSING METHODS--THE USE OF EXPANSION SERIES TYPE REGRESSION AND FUZZY PROBABILITY

  • Ikuta, Akira;Ohta, Mitsuo
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1994.06a
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    • pp.698-703
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    • 1994
  • In the actual sound environment, the random signal often shows a complex fluctuation pattern apart from a standard Gaussian distribution. In this study, an evaluation method for the sound environmnetal system is proposed in the generalized form applicable to the actual stochastic phenomena, by introducing two type information processing methods based on the regression model of expansion series type and the Fuzzy probability. The effectiveness of the proposed method are confirmed experimentally too by applying it to the observed data in the actual noise environment.

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A Spectral-spatial Cooperative Noise-evaluation Method for Hyperspectral Imaging

  • Zhou, Bing;Li, Bingxuan;He, Xuan;Liu, Hexiong
    • Current Optics and Photonics
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    • v.4 no.6
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    • pp.530-539
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    • 2020
  • Hyperspectral images feature a relatively narrow band and are easily disturbed by noise. Accurate estimation of the types and parameters of noise in hyperspectral images can provide prior knowledge for subsequent image processing. Existing hyperspectral-noise estimation methods often pay more attention to the use of spectral information while ignoring the spatial information of hyperspectral images. To evaluate the noise in hyperspectral images more accurately, we have proposed a spectral-spatial cooperative noise-evaluation method. First, the feature of spatial information was extracted by Gabor-filter and K-means algorithms. Then, texture edges were extracted by the Otsu threshold algorithm, and homogeneous image blocks were automatically separated. After that, signal and noise values for each pixel in homogeneous blocks were split with a multiple-linear-regression model. By experiments with both simulated and real hyperspectral images, the proposed method was demonstrated to be effective and accurate, and the composition of the hyperspectral image was verified.

Development of Sound Quality Evaluation System for a Printer Noise Based on Human Sensibility (프린터 소음에 대한 감성소음 평가 시스템 개발)

  • Park, Sang-Won;Lee, Hyun-Ho;Na, Eun-Woo;Lee, Sang-Kwon;Park, Yeong-Jae;Kim, Jong-Woo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.5
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    • pp.427-436
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    • 2010
  • The printer sound has many aspects which define its quality because the printer has lots of components and its operation is very complicated. These sound qualities are related to the international competition in printer markets. Recordings inside anechoic chamber were analyzed and a large number of sounds were stimulated using digital signal processing technique. First subjective tests of the printer sound were conducted using semantic different method. By applying factor analysis to the subjective response, two important factors of sound quality were extracted. Second subjective tests were conducted to evaluate the quietness and the impulsiveness of the printer sounds. On the other hand, sound metrics are calculated applying psychoacoustic theories. In this paper, the nonlinear relation between subjective evaluation and sound metrics was identified using artificial neural network and the printer sound quality index was developed. Later, subjective sound quality evaluation will be estimated and evaluated using this index.