• Title/Summary/Keyword: Partial Filter

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Evaluating Spectral Preprocessing Methods for Visible and Near Infrared Reflectance Spectroscopy to Predict Soil Carbon and Nitrogen in Mountainous Areas (산지토양의 탄소와 질소 예측을 위한 가시 근적외선 분광반사특성 분석의 전처리 방법 비교)

  • Jeong, Gwanyong
    • Journal of the Korean Geographical Society
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    • v.51 no.4
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    • pp.509-523
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    • 2016
  • The soil prediction can provide quantitative soil information for sustainable mountainous ecosystem management. Visible near infrared spectroscopy, one of soil prediction methods, has been applied to predict several soil properties with effective costs, rapid and nondesctructive analysis, and satisfactory accuracy. Spectral preprocessing is a essential procedure to correct noisy spectra for visible near infrared spectroscopy. However, there are no attempts to evaluate various spectral preprocessing methods. We tested 5 different pretreatments, namely continuum removal, Savitzky-Golay filter, discrete wavelet transform, 1st derivative, and 2nd derivative to predict soil carbon(C) and nitrogen(N). Partial least squares regression was used for the prediction method. The total of 153 soil samples was split into 122 samples for calibration and 31 samples for validation. In the all range, absorption was increased with increasing C contents. Specifically, the visible region (650nm and 700nm) showed high values of the correlation coefficient with soil C and N contents. For spectral preprocessing methods, continuum removal had the highest prediction accuracy(Root Mean Square Error) for C(9.53mg/g) and N(0.79mg/g). Therefore, continuum removal was selected as the best preprocessing method. Additionally, there were no distinct differences between Savitzky-Golay filter and discrete wavelet transform for visual assessment and the methods showed similar validation results. According to the results, we also recommended Savitzky-Golay filter that is a simple pre-treatment with continuum removal.

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Effects of high pass filter settings on P300 waveform (고역통과필터 값이 P300의 파형에 미치는 영향)

  • Eom, Jin-Sup;Eum, Young-Ji;Sohn, Jin-Hun;Park, Kwang-Bai
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.179-186
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    • 2010
  • The present study is a partial extension of the Duncan-Johnson and Donchin (1979) and Soskins, Rosenfeld, and Niendam (2001) studies that found some effects of high pass filter (HPF) setting on P300 waveform. EEGs were recorded while the subjects performed a visual three-stimulus oddball task, and the Fz and Pz EEG signals were passed through 0.01 Hz, 0.3 Hz, and 1.0 Hz HPFs. P300 amplitudes at Fz and Pz were reduced at 1.0 Hz HPF compared to 0.01 Hz and 0.3 Hz HPFs. The negative peaks post P300 at Fz and Pz were not observed at 0.01 Hz HPF, but observed at 0.3 Hz and 1.0 Hz HPFs. The combination of 0.3 Hz HPF and peak-to-peak P300 measures was more useful than that of 0.01 Hz, 0.3 Hz, or 1.0 Hz HPF and baseline-to-peak P300 measures to discriminate between non-target and standard stimuli. The peak-to-peak P300 measures were more useful than the baseline-topeak P300 measures at 1.0 Hz HPF setting.

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REAL - TIME ORBIT DETERMINATION OF LOW EARTH ORBIT SATELLITES USING RADAR SYSTEM AND SGP4 MODEL (RADAR 시스템과 SGP4 모델을 이용한 저궤도 위성의 실시간 궤도결정)

  • 이재광;이성섭;윤재철;최규홍
    • Journal of Astronomy and Space Sciences
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    • v.20 no.1
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    • pp.21-28
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    • 2003
  • In case that we independently obtain orbital informations about the low earth satellites of foreign countries using radar systems, we develop the orbit determination algorithm for this purpose using a SGP4 model with an analytical orbit model and the extended Kalman filter with a real-time processing method. When the state vector is Keplerian orbital elements, singularity problems happen to compute partial derivative with respect to inclination and eccentricity orbit elements. To cope with this problem, we set state vector osculating to mean equinox and true equator cartesian elements with coordinate transformation. The state transition matrix and the covariance matrix are numerically computed using a SGP4 model. Observational measurements are the type of azimuth, elevation and range, filter process to each measurement in a lump. After analyzing performance of the developed orbit determination algorithm using TOPEX/POSEIDON POE(precision 0.bit Ephemeris), its position error has about 1 km. To be similar to performance of NORAD system that has up to 3km position accuracy during 7 days need to radar system performance that have accuracy within 0.1 degree for azimuth and elevation and 50m for range.

Development of an Optimized Feature Extraction Algorithm for Throat Signal Analysis

  • Jung, Young-Giu;Han, Mun-Sung;Lee, Sang-Jo
    • ETRI Journal
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    • v.29 no.3
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    • pp.292-299
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    • 2007
  • In this paper, we present a speech recognition system using a throat microphone. The use of this kind of microphone minimizes the impact of environmental noise. Due to the absence of high frequencies and the partial loss of formant frequencies, previous systems using throat microphones have shown a lower recognition rate than systems which use standard microphones. To develop a high performance automatic speech recognition (ASR) system using only a throat microphone, we propose two methods. First, based on Korean phonological feature theory and a detailed throat signal analysis, we show that it is possible to develop an ASR system using only a throat microphone, and propose conditions of the feature extraction algorithm. Second, we optimize the zero-crossing with peak amplitude (ZCPA) algorithm to guarantee the high performance of the ASR system using only a throat microphone. For ZCPA optimization, we propose an intensification of the formant frequencies and a selection of cochlear filters. Experimental results show that this system yields a performance improvement of about 4% and a reduction in time complexity of 25% when compared to the performance of a standard ZCPA algorithm on throat microphone signals.

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Automatic Denoising in 2D Color Face Images Using Recursive PCA Reconstruction (2D 칼라 얼굴 영상에서 반복적인 PCA 재구성을 이용한 자동적인 잡음 제거)

  • Park, Hyun;Moon, Young-Shik
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.1157-1160
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    • 2005
  • The denoising and reconstruction of color images are increasingly studied in the field of computer vision and image processing. Especially, the denoising and reconstruction of color face images are more difficult than those of natural images because of the structural characteristics of human faces as well as the subtleties of color interactions. In this paper, we propose a denoising method based on PCA reconstruction for removing complex color noises on human faces, which is not easy to remove by using vectorial color filters. The proposed method is composed of the following five steps; training of canonical eigenface space using PCA, automatic extracting of face features using active appearance model, relighing of reconstructed color image using bilateral filter, extraction of noise regions using the variance of training data, and reconstruction using partial information of input images (except the noise regions) and blending of the reconstructed image with the original image. Experimental results show that the proposed denosing method efficiently removes complex color noises on input face images.

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Impact Point Prediction of the Ballistic Target Using a Flight Phase Discrimination (비행단계 식별 알고리즘을 이용한 초고속 표적의 탄착점 예측)

  • Jung, JaeKyung;Hwang, DongHwan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.18 no.3
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    • pp.234-243
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    • 2015
  • It is required to have the capability to predict the impact point of the ballistic target in order to assign the firing unit with high engagement possibility for the interception in the ballistic target defense systems. In this paper, a novel method is proposed to predict the impact point of the ballistic target using a flight phase discrimination algorithm given the insufficient measurements on the partial trajectory. The flight of a ballistic target is composed of a boost phase and a ballistic phase with different dynamics. The flight phase is discriminated by using the normalized innovation distance between measurements and a priori estimated measurements. The threshold and tolerance in the flight phase discrimination are determined from the probabilistic characteristics of the estimation error. Monte Carlo simulations are performed to verify the proposed method.

The Characteristics for Seepage Behaviour of Soil Structure by Modeling Tests (모형실험에 의한 토공구조물의 침투거동특성)

  • 신방웅;강종범
    • Journal of the Korean Society of Safety
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    • v.14 no.4
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    • pp.158-167
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    • 1999
  • In parallel flow condition, to estimate the stability of the extended embankment constructed on a permeable foundation ground, a laboratory model test was performed due to extended materials and water level increasing velocity of a flood period. A laboratory model test was peformed for different permeability coefficients ($K_1=2.0{\times}10^{-5}cm/sec,\;K_2=1.5{\times}10^{-4}cm/sec,\;K_3=2.3{\times}10^{-3}cm/sec$) using seepage. The fluctuation of water level occurring to an extended embankment was analyzed by laboratory model tests as vary the increasing velocity of water level with 0.6cm/min, 1.2cm/min, 2.4cm/min respectively. In analysis results, the increase of water level into embankment occurs rapidly because seepage water moving along with a permeable soil flow into embankment. The larger the permeability coefficient of an extended part is the longer initial seepage distance, and the exit point of downstream slope is gradually increased and then shows unstable seepage behavior as occurring partial collapse. As the increasing velocity of water level increase, the initial seepage line is formed low, and the discharge increases. Therefore, the embankment extended by a lower permeable soil than existing embankment shows stable seepage behavior because an existing embankment plays a role as filter for an extended part.

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Measurement of partial discharge point in power transformer using crosscorrelation (상호상관을 이용한 변압기내의 부분방전 위치측정)

  • 문영재;구춘근;정찬수;곽희로
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.7 no.6
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    • pp.34-41
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    • 1993
  • This paper describes an effort to develop a microcomputer-based parameter identification system for three phase and two phase brushless DC motor. Back EMF equation is derived from back EMF waveform of three phase and two phase brushless DC motor. In this paper, a new identification algorithm for the brushless DC motor parameters by Pasek's technique is de veloped. It is found that Pasek's equation is valid for the brushless DC motor, too. The results obtained clearly shows that it is possible to implement the identification system for the determination of the brushless DC motor parameters. To minimize errors due to the ripple component in the measured armature current, dlgital averaging filter is employed. The whole identification process of signal generation, measuring, parameter determination is fully automated. The use of the pmpased method in the parameter identification system shows that the averaged current curve is in excellent agreement with the estimated current curve. Therefore, this close agreement conf i i the validity of this technique.

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Evaluation of Improvement on Sediment for Practical Application in Prawn Farm (새우 양식장에 적용을 위한 저질개선 평가)

  • Kim Woo-Hang;Kim Doo Hee
    • Proceedings of KOSOMES biannual meeting
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    • 2004.05b
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    • pp.81-84
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    • 2004
  • Control of Sediment is very important in prawn farm due to the eruption of toxic material such as W1ionized H2S, NH3 and NO2-. In this study, column test study, column with filter media such as activated carbon, zeolite, oyster shell and iron chloride to evaluate the reduction of toxicity from sediment ammonia-N(NH3) was effectively removed by Zeolite and oyster shell. It was indicated that ammonium ion(NH4+) was removed by ion exchange of zeolite. And the ammonia in the column of oyster shell was existed as the form of NH4+, which is not toxic for prawn because oyster shell was stably kept around pH 8. Therefore, some of ammonia(NH3) was reduced by oyster shell. Hydrogen sulfide and COD were effectively removed by adsorption of activated carbon and a partial removal of hydrogen sulfide was accomplished by Oyster shell. Phosphorous was removed by activated carbon, oyster shell and iron chloride. In prawn farm, the concentration of ammonia was increased with increase of pH by algae photosynthesis in the column of activated carbon, zeolite and iron chloride, but it was revealed that pH was stably kept in the column of oyster shell.

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A New Approach for Information Security using an Improved Steganography Technique

  • Juneja, Mamta;Sandhu, Parvinder Singh
    • Journal of Information Processing Systems
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    • v.9 no.3
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    • pp.405-424
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    • 2013
  • This research paper proposes a secured, robust approach of information security using steganography. It presents two component based LSB (Least Significant Bit) steganography methods for embedding secret data in the least significant bits of blue components and partial green components of random pixel locations in the edges of images. An adaptive LSB based steganography is proposed for embedding data based on the data available in MSB's (Most Significant Bits) of red, green, and blue components of randomly selected pixels across smooth areas. A hybrid feature detection filter is also proposed that performs better to predict edge areas even in noisy conditions. AES (Advanced Encryption Standard) and random pixel embedding is incorporated to provide two-tier security. The experimental results of the proposed approach are better in terms of PSNR and capacity. The comparison analysis of output results with other existing techniques is giving the proposed approach an edge over others. It has been thoroughly tested for various steganalysis attacks like visual analysis, histogram analysis, chi-square, and RS analysis and could sustain all these attacks very well.