• Title/Summary/Keyword: average error

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Block Error Performance of Transmission in Slow Nakagami Fading Channels with Diversity

  • Kim, Young-Nam;Kang, Heau-Jo;Chung, Myung-Rae
    • Journal of information and communication convergence engineering
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    • v.1 no.3
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    • pp.119-122
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    • 2003
  • In this paper presents equations which describe an average weighted spectrum of errors and average block error probabilities for noncoherent frequency shift keying (NCFSK) used in D-branch maximal ratio combining (MRC) diversity in independent very slow nonselective Nakagami fading channels. The average is formed over the instantaneous receiver signal to noise ratio (SNR) after combining. the analysis is limited to additive Gaussian noise.

BOUNDS OF ZERO MEAN GAUSSIAN WITH COVARIANCE FOR AVERAGE ERROR OF TRAPEZOIDAL RULE

  • Hong, Bum-Il;Choi, Sung-Hee;Hahm, Nahm-Woo
    • Journal of applied mathematics & informatics
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    • v.8 no.1
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    • pp.231-242
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    • 2001
  • We showed in [2] that if r≤2, zero mean Gaussian of average error of the Trapezoidal rule is proportional to h/sub i//sup 2r+3/ on the interval [0,1]. In this paper, if r≥3, we show that zero mean Gaussian of average error of the Trapezoidal rule is bounded by Ch⁴/sub i/h⁴/sub j/.

Simulation of Average Bit Error Rate for Computer Hard Disk Drive System Using Planar Silicon Head (평면 실리콘 헤드를 사용한 하드 디스크 드라이브 시스템의 Average Bit Error Rate 시뮬레이션)

  • 서정욱;조순철;김용수;노광춘
    • Journal of the Korean Magnetics Society
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    • v.8 no.6
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    • pp.395-399
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    • 1998
  • 평면 실리콘 헤드를 사용한 디스크 드라이브(hard disk:HDD) 시스템의 average bit error rate(ABER)를 계산하였다. ABER을 구하기 위해 3차원 유한 요소법을 사용하여 헤드 자장 분포를 구하고 error rate response surface(ERRS)를 구하엿다. 다음에 track misregistration(TMR)과 계산되어진 ERRS를 컨볼루션하여 ABER을 시뮬레이션 하였다. 허용할 수 잇는 에러 율이 10-6이라 하고 트랙 피치가 3.7$\mu$m일 때, 요구되는 TMR은 0.36$\mu$m이었다. 이는 트랙 피치의 9.7이었다.

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An Adaptive Algorithm for the Quantization Step Size Control of MPEG-2

  • Cho, Nam-Ik
    • Journal of Electrical Engineering and information Science
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    • v.2 no.6
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    • pp.138-145
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    • 1997
  • This paper proposes an adaptive algorithm for the quantization step size control of MPEG-2, using the information obtained from the previously encoded picture. Before quantizing the DCT coefficients, the properties of reconstruction error of each macro block (MB) is predicted from the previous frame. For the prediction of the error of current MB, a block with the size of MB in the previous frame are chosen by use of the motion vector. Since the original and reconstructed images of the previous frame are available in the encoder, we can calculate the reconstruction error of this block. This error is considered as the expected error of the current MB if it is quantized with the same step size and bit rate. Comparing the error of the MB with the average of overall MBs, if it is larger than the average, small step size is given for this MB, and vice versa. As a result, the error distribution of the MB is more concentrated to the average, giving low variance and improved image quality. Especially for the low bit application, the proposed algorithm gives much smaller error variance and higher PSNR compared to TM5 (test model 5).

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A Study of the New Body Surface Area Calculation for Twenties Women (20대 여성을 위한 새로운 체표면적 산출식에 관한 연구)

  • Im, Soon
    • The Research Journal of the Costume Culture
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    • v.7 no.2
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    • pp.275-288
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    • 1999
  • The purpose of this is providing a simple, relatively errorless body surface area calculation. Subjects were 10 married women and 10 singles women whose age was 20 to 29 years old. The Gypsum method has applied for the sampling of body surface. The Weight method has been used to measure body surface by means of transferring gypsum shape on uniform plane polypropylene films. In this study, compare analyzed errors between the traditional formulas for measuring body surface area and measuring data in this experiment. More than all, it has been to induce a regression equation for measuring body surface area, which is so simple to calculate with less errors, with variable factors as weight and height. The results of this experiment as follows : 1. In the traditional formulas, weight formula was shown high average error : Niya\`s height formula. which was modified K value as 0.62 in the height formula (S = KH) is shown lower average error than Lassabliere\`s Height formula. 2. In the weight-height formula (S=K √WH), it was shown high average error according to the increasing of K value. Kawanami\`s formula, which 5.378 as K value, was shown low average error both the singles and the married women. 3. Dubois weight-heingt formula (S=W/sup a/·H/sub b/·K) was shown low average error than the weight, height, weight-height (S=K√WH) formula. 4. The regression equations with variable factors as weight and height are 156.74W + 86.05H - 660.25 (Single women) and 136.02W + 90.57H - 6241.32 (Married women) the average error and absolute average error to the singles are 0.09%, 0.94% and resoectively -0.13%, 1.16% for the married women.

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Rainfall Seasonality and Estimation Errors of Area-Average Rainfall (강수의 계절성과 면적평균강수량의 추정오차)

  • Yoo, Chul-Sang
    • Journal of Korea Water Resources Association
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    • v.35 no.5
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    • pp.575-581
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    • 2002
  • This study evaluates the variation of estimation error of area-average rainfall due to rainfall seasonality. Both the cases considering and not considering the spatial correlation are compared to derive the characteristics of estimation error. Similar cases with different accumulation time without considering the rainfall seasonality are also investigated. This study was applied to the Geum-river basin with total 28 rain gauge measurements haying more than 30 years of daily rainfall measurements. As results of the study we found that: (1) The absolute estimation error of monthly area-average rainfall show strong seasonality like the total rainfall amount. However, the relative estimation error normalized by its mean was estimated to have similar values about 5 to 8% except January and December. (2) The relative estimation error of annual area-average rainfall estimated was found to have the estimation error about 3% of its annual mean. (3) However, the relative estimation error normalized by the standard deviation remains almost the same for both monthly and annual rainfall amounts, which was estimated about 11% of its standard deviation. (4) Finally, the estimation error without considering the spatial correlation was found to become almost twice the estimation error with considering the spatial correlation.

Study of New Approach of Performance Analysis for OADF Relay Systems over Rayleigh Fading channels (레일리 페이딩 채널에서의 OADF 릴레이 시스템에 대한 새로운 성능분석 기법에 관한 연구)

  • Ko, Kyun-Byoung;Seo, Jeong-Tae
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.3
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    • pp.188-193
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    • 2011
  • In this letter, we have derived another exact performance analysis for the OADF(opportunistic adaptive decode-and-forward) relay systems over Rayleigh fading channels. Based on error-events at relay nodes, the received instantaneous SNR(signal-to-noise ratio) is presented and its PDF(probability density function) is expressed as a more tractable form in which the number of summations and the length of each summation are specified. Then, exact average error rate, outage probability, and average channel capacity are obtained as general forms. Simulation results are finally presented to validate that the proposed analytical expressions can be a unified frame work covering all Rayleigh fading channel conditions. Furthermore, it is confirmed that OADF schemes can outperform the other schemes on the average error rate, outage probability, and average channel capacity.

Sampling Error of Areal Average Rainfall due to Radar Partial Coverage (부분적 레이더 정보에 따른 면적평균강우의 관측오차)

  • Yoo, Chul-Sang;Kim, Byoung-Soo;Kim, Kyoung-Jun;Yoon, Jung-Soo
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.97-100
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    • 2008
  • This study estimated the error involved in the areal average rainfall derived incomplete radar information due to radar partial coverage of a basin or sub-basin. This study considers the Han River Basin as an application example for the rainfall observation using the Ganghwa rain radar. Among the total of 24 mid-sized sub-basins of the Han River Basin evaluated in this study, only five sub-basins are fully covered by the radar and three are totally uncovered. Remaining 16 sub-basins are partially covered by the radar leading incomplete radar information available. When only partial radar information is available, the sampling error decreases proportional to the size of the radar coverage, which also varies depending on the number of clusters. It is general that smaller sampling error can be expected when the number of clusters increases if the total area coverage remains the same. This study estimated the sampling error of the areal average rainfall of partially-covered mid-sized sub-basins of the Han River Basin, and the results show that the sampling error could be at least several % to maximum tens % depending on the relative coverage area.

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A Study on the Distance Error Correction of Maritime Object Detection System (해상물체탐지시스템 거리오차 보정에 관한 연구)

  • Byung-Sun Kang;Chang-Hyun Jung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.139-146
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    • 2023
  • Maritime object detection systems, which detects small maritime obstacles such as fish farm buoys and visualizes distance and direction, is equipped with a 3-axis gimbal to compensate for errors caused by hull motion, but there is a limit to distance error corrections necessitated by the vertical movement of the camera and the maritime object due to wave motions. Therefore, in this study, the distance error of maritime object detection systems caused by the movement of the water surface according to the external environment is analyzed and corrected using average filter and moving average filter. Random numbers following a Gaussian standard normal distribution were added to or subtracted from the image coordinates to reproduce the rise or fall of the buoy under irregular waves. The distance calculated according to the change of image coordinates, the predicted distance through the average filter and the moving average filter, and the actual distance measured by laser distance meter were compared. In phases 1 and 2, the error rate increased to a maximum of 98.5% due to the changes of image coordinates due to irregular waves, but the error rate decreased to 16.3% with the moving average filter. This error correction capability was better than with the average filter, but there was a limit due to failure to respond to the distance change. Therefore, it is considered that use of the moving average filter to correct the distance error of the maritime object detection system will enhance responses to the real-time distance change and greatly improve the error rate.

ERROR BOUNDS FOR SUMPSONS QUADRATURE THROUGH ZERO MEAN GEUSSIAN WITH COVARIANCE

  • Hong, Bum-Il;Choi, Sung-Hee;Hahm, Nahm-Woo
    • Communications of the Korean Mathematical Society
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    • v.16 no.4
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    • pp.691-701
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    • 2001
  • We computed zero mean Gaussian of average error bounds pf Simpsons quadrature with convariances in [2]. In this paper, we compute zero mean Gaussian of average error bounds between Simpsons quadrature and composite Simpsons quadra-ture on four consecutive subintervals. The reason why we compute these on subintervals is because these results enable us to compute a posteriori error bounds on the whole interval in the later paper.

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