• Title/Summary/Keyword: Standard error of mean

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Analysis of Distance Measurement Accuracy in Aerial and Satellite Image Photogrammetry (항공사진측량과 위성영상측량에서 거리측정 정확도 연구)

  • Kim, Hyung-Moo;Tcha, Dek-Kie;Nam, Guon-Mo;Yang, Chul-Soo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.253-255
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    • 2010
  • Needs to study on distance measurement accuracy in aerial and satellite photogrammetry are rapidly increased. However, conventional studies show some confused definitions between measurement accuracy and measurement precision as well as standard deviation(STDEV) and root mean square error(RMSE or RMSD). So, Finite definitions of measurement accuracy and measurement precision as well as STDEV and RMSD are addressed in this paper. Experiment result show using correct definitions improve the distance measurement accuracy in aerial and satellite photogrammetry rapidly, but not the distance measurement accuracy in aerial and satellite photogrammetry.

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Development and Validation of Sky Simulator for Reproducing CIE Overcast Sky Model (돔형 인공천공의 개발 및 CIE표준담천공 구현 검증에 관한 연구)

  • Shin, Ju Young;Yun, Geun Young;Kim, Jeong Tai
    • KIEAE Journal
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    • v.10 no.6
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    • pp.97-103
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    • 2010
  • Sky simulator is a effective daylighting design tool that can evaluate three dimensional performance of lighting. Especially, the dome type sky simulator offer reliable and reproducible daylighting performance with different standard sky models. Recently, K university has developed the dome type sky simulator(sky dome) with the diameter of 6.5m and the height of 3.7m. The sky dome consists of a group of 145 large steel panels with 72 halogen lamps which are arranged in a circular array. The luminance distribution of the sky dome can be calibrated by changing the angle and the brightness of the lamps respectively. To allow more reliable prediction and evaluation of daylighting through the sky dome, It is essential to validate the sky luminance distribution of the sky dome. This study consider the validation of the comparisons between the measured and the calculated luminance values for the CIE standard overcast sky. Also, the error rate between the measured and the calculated luminance values were compared to the previous studies. The results indicated that the K university sky dome can reproduce reliable CIE standard overcast sky with the average relative error rate of 4.4% and root-mean-square error(RMSE) of 5.4%.

Analysis of Medical Errors in Operating Room Nursing using Web;based Error Reporting System (수술 간호업무 중 발생한 의료오류의 분석;웹기반 보고체계를 적용하여)

  • Kim, Myoung-Soo
    • Journal of Korean Academy of Nursing Administration
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    • v.12 no.3
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    • pp.397-405
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    • 2006
  • Purpose: The purpose of this study was to develop the medical error reporting system and to validate an trait of error in the Operating Room. Methods: Descriptive research design was used. The subjects were 30 nurses with below 5-year-career in a University Hospital. Data was collected from 11, April until 22, April, 2005 using web-based error reporting system. Data was analyzed by mean, standard deviation, $X^{2}-test$ using SPSS WIN 10.0 program. Results: A time of medical error in operating room nursing frequent occurrence was from 12 pm. to 4pm. 'Lack of sterile materials' management' was the best frequent occurrence of medical error in operating room nursing. Conclusion: The findings of this study show that manager of healthcare organization must develop the error reporting system more familiar and ordinary. Afterward, we prevent the repetitive medical errors in nursing care through analyzing of error reporting system.

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Effect of Channel Estimation Error on Capacity of MIMO Systems (MIMO 시스템의 채널 용량에 대한 채널 추정 오차의 영향 분석)

  • 함재상;심세준;이충용;박현철;홍대식
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.8
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    • pp.63-68
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    • 2004
  • The capacity of MIMO systems is numerically analyzed when channel estimation error exists. The analysis shows that the capacity is influenced by Mean Square Error (MSE) as well as average Signal to Noise Ratio (SNR). Furthermore, in this paper we present the standard selecting a channel estimator suitable to a system owing to get a tolerable channel estimation error in a given average SNR and channel capacity loss. The simulation results show that the tolerable MSEs for 1 bps/Hz capacity loss are about 10$^{-2}$ and 10$^{-4}$ at n dB and 40 dB average SNR, respectively.

Large-Sample Comparisons of Statistical Calibration Procedures When the Standard Measurement is Also Subject to Error: The Replicated Case

  • Lee, Seung-Hoon;Yum, Bong-Jin
    • Journal of the Korean Statistical Society
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    • v.17 no.1
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    • pp.9-23
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    • 1988
  • The classicla theory of statistical calibration assumes that the standard measurement is exact. From a realistic point of view, however, this assumption needs to be relaxed so that more meaningful calibration procedures may be developed. This paper presents a model which explicitly considers errors in both standard and nonstandard measurements. Under the assumption that replicated observations are available in the calibration experiment, three estimation techniques (ordinary least squares, grouping least squares, and maximum likelihood estimation) combined with two prediction methods (direct and inverse prediction) are compared in terms of the asymptotic mean square error of prediction.

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Discrete-Time Analysis of Throughput and Response Time for LAP Derivative Protocols under Markovian Block-Error Pattern (마르코프 오류모델 하에서의 LAP 계열 프로토콜들의 전송성능과 반응시간에 대한 이산-시간 해석)

  • Cho, Young-Jong;Choi, Dug-Kyoo
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.11
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    • pp.2786-2800
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    • 1997
  • In this paper, we investigate how well the channel memory (statistical dependence in the occurrence of transmission errors) can be used in the evaluation of widely used error control schemes. For this we assume a special case named as the simplest Markovian block-error pattern with two states, in which each block is classified into two classes of whether the block transmission is in error or not. We apply the derived pattern to the performance evaluation of the practical link-level procedures, LAPB/D/M with multi-reject options, and investigate both throughput and user-perceived response time behaviors on the discrete-time domain to determine how much the performance of error recovery action is improved under burst error condition. Through numerical examples, we show that the simplest Markovian block-error pattern tends to be superior in throughput and delay characteristics to the random error case. Also, instead of mean alone, we propose a new measure of the response time specified as mean plus two standard deviations 50 as to consider user-perceived worst cases, and show that it results in much greater sensitivity to parameter variations than does mean alone.

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Determination of Chemical Composition of Toasted Burley Tobacco by Near Infrared Spectroscopy (근적외선분광법을 이용한 버어리 토스트엽의 화학성분 분석)

  • 김용옥;정한주;백순옥;김기환
    • Journal of the Korean Society of Tobacco Science
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    • v.17 no.2
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    • pp.177-183
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    • 1995
  • This study was conducted to develop the most precise NIR(near infrared spectrometric) calibration for rapid determination of chemical composition in ground samples of toasted burley tobacco using stepwise, stepup, principal component regression(PCR), partial least square(PLS) and modified partial least square(MPLS) calibration method. The number of wavelength(W) selected by stepup multiple linear regression using: second derivative spectra was as follows: total sugar(TS)-4 W, nicotine-9 W, total nitrogen(TN)-2 W, ash-8 W, total volatile base(TVB)-5 W, chlorine4 W, L of color-6 W, a of color-6 W and b of color-7 W. Comparing the calibration equations followed by each chemical components, the most precise calibration equation was MPLS for 75, a and b of color, PLS for nicotine, ash, TVB, chlorine and L of color and stepup for TN. The standard error of calibration(SEC) and standard error of performance(SEP) between result of near infrared analysis and standard laboratory analysis were 0.18, 0.40% for 75, 0.06, 0.08% for nicotine, 0.18, 0.16% for TN, 0.33, 0.46% for ash, 0.04, 0.03% for TVB, 0.08, 0.06% for chlorine, 0.54, 0.58 for L of color, 0.22, 0.22 for a of color and 0.27, 0.27 for b of color, respectively. The SEC and SEP of ash and TVB were within allowable error of standard laboratory analysis, nicotine, TN and chlorine were 1.2-2.0 times and 75 were 2.1-4.0 times larger than allowable error of standard laboratory analysis. The ratio of SEC and SEP to mean were 1.5, 1.6% for L of color, 3.7, 3.8% for a of color and 1.8, 1.8% for b of color, respectively. Key words : burley tobacco chemistry, near infrared spectroscopy.

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New mathematical approach to determine solar radiation for the southwestern coastline of Pakistan

  • Atteeq Razzak;Zaheer Uddin;M. Jawed Iqbal
    • Advances in Energy Research
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    • v.8 no.2
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    • pp.111-123
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    • 2022
  • Solar Energy is the energy of solar radiation carried by them in the form of heat and light. It can be converted into electricity. Solar potential depends on the site's atmosphere; the solar energy distribution depends on many factors, e.g., turbidity, cloud types, pollution levels, solar altitude, etc. We estimated solar radiation with the help of the Ashrae clear-sky model for three locations in Pakistan, namely Pasni, Gwadar, and Jiwani. As these locations are close to each other as compared to the distance between the sun and earth, therefore a slight change of latitude and longitude does not make any difference in the calculation of direct beam solar radiation (BSR), diffuse solar radiation (DSR), and global solar radiation (GSR). A modified formula for declination angle is also developed and presented. We also created two different models for Ashrae constants. The values of these constants are compared with the standard Ashrae Model. A good agreement is observed when we used these constants to calculate BSR, DSR, GSR, the Root mean square error (RMSE), Mean Absolute error (MABE), Mean Absolute percent error (MAPE), and chisquare (χ2) values are in acceptance range, indicating the validity of the models.

A Study on the Standard Link-based Travel Speed Calculation System Using GPS Tracking Information (GPS 운행궤적정보를 이용한 표준링크기반 통행속도 산출 시스템 연구)

  • Song, Gil jong;Hwang, Jae Seon;Lim, Jae Jung;Jung, Eui Yong
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.5
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    • pp.142-155
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    • 2019
  • This study was conducted with the aim of developing a system to collect taxi GPS probe information to prevent link defects and to improve the accuracy of the standard link-based travel speed by determining when to go into and come out the link. For this purpose, a framework and algorithm consisting of a five-step process for standard link-based map matching and individual vehicle travel speed are presented and used it to calculate the average travel speed of the service link. Two on-site surveys of Teheran and Hakdong-ro were conducted to verify the results by the methods proposed in this paper. On the basis of the overall time of the field survey, the deviation in the travel speed was 0.2 km/h and 0.6 km/h, the accuracy was 99% and 96%, and the MAPE(Mean Absolute Percentage Error) was 1% and 4% in Teheran and Hakdong-ro, respectively. These results were more accurate thand those obtained using conventional methodologies without standard links.

Statistical Efficiency of Sampling Plot Size in Half-sib Progeny Test of Korean Pine (Pinus koraiensis S. et Z.) (잣나무 차대검정(次代檢定)에 있어서의 효율적(效率的)인 Plot Sampling에 관(關)한 연구(硏究))

  • Kim, Dae Eun;Chon, Sang Keun
    • Journal of Korean Society of Forest Science
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    • v.80 no.4
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    • pp.379-382
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    • 1991
  • Tree height at age 10 was used to estimate the statistical efficiencies of sampling size in the progeny test of Pinus koraiensis S. et Z. Experimental design was RCB design which consists of 25 half-sib families in each of three blocks. The number of families and blocks were fixed, therefore, the number of trees sampled per plot was the only factor that influences the environmental portion of the family mean height. Coefficient of variation, the estimate of the standard error of the family mean height, decreased with increase of sampling plot size, and became stable from 4-tree plot sampling (6.97%). The experimental error was significant from 7-tree sampling plot size. Nonlinear relationship (${\hat{Y}}=10.425e-^{0.073x}$ ; $R^2$=0.840) was found between the sampling plot size and the standard error of family mean height.

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