• Journal of the Korean Society of Tobacco Science
• /
• v.27 no.1 s.53
• /
• pp.94-99
• /
• 2005

To correct the difference of filling volumn for various cut tobacco and puffed stem according to moisture contents, correction equation was estamated by a simple regression analysis. The $R^2$(coefficient of determination) of correction equation was above 0.95. To verify the precision of correction equation, we predicted correction equation of other samples. The filling volumns by the difference of $1\%$ moisture content were $0.018\;~\;0.022cc/g$ (cut tobacco) and 0.060cc/g (puffed stem). The precision of correction equation for various cut tobacco was very high, but that of puffed stem was low due to quality deviation of row stem according to a season.

• Journal of Biosystems Engineering
• /
• v.35 no.3
• /
• pp.175-181
• /
• 2010

This study compared moisture content measured by moisture meter of microwave resistance type(MMMRT) and standard moisture content of paddy, and developed the correction equation using linear and curvilinear regression analysis, and to explore its significance test. The correction factor according to the range of moisture content was developed to improve the measurement precision of MMMRT. The results were as followings. The coefficients of determination of correction equation by linear and curvilinear regression analysis with comparing the MMMRT and standard moisture content were 0.946 and 0.968, respectively. The moisture content error of MMMRT and standard moisture content measured after the MMMRT were corrected by moisture content rate of every 5% using the correction equation by curvilinear regression analysis appeared with 0~0.5% and 0.9~1.8% respectively in the moisture content range of 15~20% and 20~25%.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.21 no.3
• /
• pp.341-349
• /
• 1997

The characteristics of defect correction method are discussed in a sample heat conduction problem showing the numerical solution of the error correction equation can predict the error of the numerical solution of the original governing equation. A way of using defect correction method combined with the existing algorithm for the incompressible fluid flow, is proposed and subsequently tested for the driven square cavity problem. The error correction equations for the continuity equation and the momentum equations are considered to estimate the errors of the numerical solutions of the original governing equations. With this new approach, better velocity and pressure fields can be obtained by correcting the original numerical solutions using the estimated errors. These calculated errors also can be used to estimate the orders of magnitude of the errors of the original numerical solutions.

• Journal of Power System Engineering
• /
• v.18 no.6
• /
• pp.70-76
• /
• 2014

Surely fuel economy(F.E.) label is needed to meet consumer's right to know. Korea has developed and adopted F.E. correction equation similar to the feeling, because consumer complain about F.E. label higher than they feel. Recently, through continuous research and development high-efficiency & performance green car like HEV, PHEV and EV are being sold. In this situation, it is needed to know whether the current equation can reflect a part of their improved technic or not. In this paper, to review current equation through test using hybrid vehicles on 5-cycle SOC, correction equation and F.E were discussed. The result show HEV didn't meet the SOC error standard on US06. Also, HEV has bigger F.E. difference between FTP-75 and 5-cycle than conventional vehicles. However, the correction equation that include HEV almost same with current one.

• Journal of Korean Society of Forest Science
• /
• v.85 no.1
• /
• pp.56-65
• /
• 1996

Current volume tables might underestimate or overestimate the volumes of individual trees in a specific region because the tables were made using the data from broad region. This study provides a statistical method of local correction, which is the ratio-of-means estimator, when the table is applied to the data from a specific region. Data used in this study were 411 trees of Larix leptolepis from Hongchon region. Five statistical models for individual tree volume equation were evaluated based on 3 evalation criteria and the best equation fitted to the data from Hongchon region was selected. The volume estimated by the selected equation was then compared with the volume estimated by the current volume table. From the ratio-of-means estimate based on the volumes estimated by selected equation and by current volume table, the local correction was made. The correction equation was $V_{Hongchon}=1.078$ $V_{volume\;table}$. It is also proved that the correction equation can simply and precisely estimate tree volumes of Larix leptolepis in Hongchon region using the current volume table.

• Korean Journal of Remote Sensing
• /
• v.35 no.6_4
• /
• pp.1373-1389
• /
• 2019

KOMPSAT-5 is the first satellite in Korea equipped with X-band Synthetic Aperture Radar (SAR) instrument and has been operated since August 2013. KOMPSAT-5 is used to monitor the global environment according to its observation purpose and the availability of KOMPSAT-5 is also highlighted as the need of high resolution wind data for investigating the coastal region. However, the previous study for the validation of wind derived from KOMPSAT-5 showed that the accuracy is lower than that of other SAR satellites. Therefore, in this study, we developed the correction equation of normalized radar cross section (NRCS or backscattering coefficient) for improvement of wind from the KOMPSAT-5 and validated the effect of the equation using the in-situ measurement of ocean buoys. Theoretical estimated NRCS and observed NRCS from KOMPSAT-5 showed linear relationship with incidence angle. Before applying the correction equation, the accuracy of the estimated wind speed showed the relatively high root-mean-square errors (RMSE) of 2.89 m s^-1 and bias of -0.55 m s^-1. Such high errors were significantly reduced to the RMSE of 1.60 m s^-1 and bias of -0.38 m s^-1 after applying the correction equation. The improvement effect of the correction equation showed dependency relying on the range of incidence angle.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.38 no.3
• /
• pp.193-200
• /
• 1989

The errors of activation energy calculated by the initial rise method from the characteristics of thermally stimulated current have been estimated and an equation for the correction of the error is proposed. The coefficients needed in the proposed equation are determined by the numerical method. It is shown that the activation energy calculated by the conventional initial rise method contains errors of 0.7-10% depending on the location of the data points of the interval on which the method is applied. However, the error can be reduced to less than 0.5% when corrected by using the proposed equation. It is finally concluded that the activation energy determined by the initial rise method can approach the true value by adapting the proposed error correction method which is effective and reliable.

• The Korean Journal of Applied Statistics
• /
• v.29 no.1
• /
• pp.75-83
• /
• 2016

We propose methodology to analyze the dynamic mechanisms of financial market contagion under market integration using a biological contagion analytical approach. We employ U-statistic to measure market integration, and a dynamic model based on an error correction mechanism (single equation error correction model) and latent factor model to examine market contagion. We also use quantile regression and Wald-Wolfowitz runs test to test market contagion. This methodology is designed to effectively handle heteroscedasticity and correlated errors. Our simulation results show that the single equation error correction model fits well with the linear regression model with a stationary predictor and correlated errors.

• Journal of Astronomy and Space Sciences
• /
• v.28 no.4
• /
• pp.267-271
• /
• 2011

I developed an enhanced correction method for Ricean bias which occurs in linear polarization measurement. Two known methods for Ricean bias correction are reviewed. In low signal-to-noise area, the method based on the mode of the equation gives better representation of the fractional polarization. But a caution should be given that the accurate estimation of noise level, i.e. ${\sigma}$ of the polarized flux, is important. The maximum likelihood method is better choice for high signal-to-noise area. I suggest a hybrid method which uses the mode of the equation at the low signal-to-noise area and takes the maximum likelihood method at the high signal-to-noise area. A modified correction coefficient for the mode solution is proposed. The impact on the depolarization measure analysis is discussed.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.42 no.6
• /
• pp.106-114
• /
• 2000

In order to evaluate the shear characteristics of undisturbed weathered granite soil which is a typical residual soil in Korea, the mechanical properties are first investigated and discussed by carrying out a series of direct shear test and then dilatancy correction is performed by using Taylor’s correction equation. In this study, specimens are sampled at Pungam(-3, -8, -13m below ground surface), Kwangju and Iksan(-5m below ground surface), Jeonbuk. The test results are summarized as follows: 1) Mohr-Coulomb failure criterion is not linear under the low confining pressure. 2) The value of cohesion is smaller than usually determined value in low pressure region. 3) The value of strength parameter c and ø which are corrected by Taylor’s correction equation is a little bit small.