• The Journal of the Society of Korean Medicine Diagnostics
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• v.16 no.1
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• pp.9-18
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• 2012

Objectives The aim of this study is to propose an optimized tongue colour interpolation method to achieve accurate tongue image rendering. Methods We selected 60 colour chips in the chips of DIC color guide selector, and then divided randomly the colour chips into two groups. The colour chips of a group (Gr I) were used for finding the optimized colour correction factor of error and those of the other group (Gr II) were used for verifying the correction factor. We measured colour value of the Gr I colour chips with spectrophotometer, and took the colour chips image with a digital tongue image system (DTIS). We adjusted colour correction factor of error to equal the chip colour from each method. Through that process, we obtained the optimized colour correction factor. To verify the correction factor, we measured colour value of the Gr II colour chips with a spectrophotometer, and took the colour chips image with the DTIS in the two types of colour interpolation mode (auto white balance mode and optimized colour correction factor mode). And then we calculated the CIE-$L^*ab$ colour difference (${\Delta}E$) between colour values measured with the spectrophotometer and those from images taken with the DTIS. Results In auto white balance mode, The mean ${\Delta}E$ between colour values measured with the spectrophotometer and those from images taken with the DTIS was 13.95. On the other hand, in optimized colour correction factor mode, The mean ${\Delta}E$ was 9.55. The correction rate was over 30%. Conclusions In case of interpolating colour of images taken with the DTIS, we suggest that procedure to search the optimized colour correction factor of error should be done first.

• Journal of Positioning, Navigation, and Timing
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• v.3 no.1
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• pp.17-23
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• 2014

Satellite Based Augmentation Systems (SBAS) provide ionospheric corrections at geographically five degree-spaced Ionospheric Grid Points (IGPs) and confidence bounds, called Grid Ionospheric Vertical Errors (GIVEs), on the error of those corrections. Since the ionosphere is one of the largest error sources which may threaten the safety of a single frequency Global Navigation Satellite System (GNSS) user, the ionospheric correction and integrity bound algorithm is essential for the development of SBAS. The current single frequency based SBAS, already deployed or being developed, implement the ionospheric correction and error bounding algorithm of the Wide Area Augmentation System (WAAS) developed for use in the United States. However, the ionospheric condition is different for each region and it could greatly degrade the performance of SBAS if its regional characteristics are not properly treated. Therefore, this paper discusses key factors that should be taken into consideration in the development of the ionospheric correction and integrity bound algorithm optimized for the Korean SBAS. The main elements of the conventional GIVE monitor algorithm are firstly reviewed. Then, this paper suggests several areas which should be investigated to improve the availability of the Korean SBAS by decreasing the GIVE value.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.83-88
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• 2006

We intend to increase in efficiency of the topographic monitoring of seabed or riverbed by combined with DGPS, RTK GPS and echo sounder. For this study, we defined the error correction of the echo sounder with the experiment of water tank, which is considered the characteristic of estuary riverbed and then we developed the s/w for 3-dimensional monitoring of estuary riverbed and applied the s/w to field test and improved the various problems. On analyzing topography of estuary riverbed by combined GPS with echo sounder, the draught error which is yielded to change of length from the water surface by the movement of survey vessel to the end of the transducer was eliminated by geometrical rearrangement and we defined the correction formula, z = BM+ SAH- $DBR_{(i)}$ - DRT - ED. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter and residual error and we defined correction formula, Y= -0.00474*In(X) -0.0045 by the regression analysis. and then we verified applicability of correction formula.

• The Journal of Korean Association of Computer Education
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• v.3 no.2
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• pp.115-127
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• 2000

Korean error detectors of word processors have defects such as inconvenience that users choose one of error groups, lower detecting rate of 60%, and slow processing time. In this study, I proposed a resolution method of these defects. For these, I applied bidirectional longest match strategy for morphological analysis to improve processing time. I suggested dictionaries and several algorithms such as seperation of compound noun and assistant declinable words, correction of typing error to improve processing time and to guarantee correction accuracy. I also suggested a distinguishable method for dependent noun/suffix and Josa/Eomi where many ambiguities are generated, and a distinguishable method for Korean "로써/로서" to improve the reliability of the correction system.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.1
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• pp.1-9
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• 2012

A 10-b 500 MS/s A/D converter (ADC) with a hybrid calibration and error correction logic is described. The ADC employs a single-channel cascaded folding-interpolating architecture whose folding rate (FR) is 25 and interpolation rate (IR) is 8. To overcome the disadvantage of an offset error, we propose a hybrid self-calibration circuit at the open-loop amplifier. Further, a novel prevision digital error correction logic (DCL) for the folding ADC is also proposed. The ADC prototype using a 130 nm 1P6M CMOS has a DNL of ${\pm}0.8$ LSB and an INL of ${\pm}1.0$ LSB. The measured SNDR is 52.34-dB and SFDR is 62.04-dBc when the input frequency is 78.15 MHz at 500 MS/s conversion rate. The SNDR of the ADC is 7-dB higher than the same circuit without the proposed calibration. The effective chip area is $1.55mm^2$, and the power dissipates 300 mW including peripheral circuits, at a 1.2/1.5 V power supply.

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

• Environmental and Resource Economics Review
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• v.27 no.3
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• pp.521-544
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• 2018

This paper investigates the impact of ethanol mandate on the price relationship between corn and beef using the monthly time-series data from January 2003 through December 2013. In addition, we examine the non-linearity in ethanol, corn, and beef markets. Based on the threshold cointegration test, we find the symmetric relationship in pairs with ethanol production-corn price and ethanol production-beef price whereas there is the asymmetric relationship between prices of corn and beef. Employing the threshold vector error correction and vector error correction models, we also find that the corn price in the U.S is caused by both ethanol production and beef price in a long-run when the beef price is relatively high. On the other hand, the corn price does not cause both ethanol production and beef price in the long run. Findings from this study imply that demanders for corn such as ethanol and beef producers have price leadership on corn producers.

• Journal of Environmental Science International
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• v.28 no.1
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• pp.125-135
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• 2019

For the purposes of enhancing usability of Numerical Weather Prediction (NWP), the quantitative precipitation prediction scheme by machine learning has been proposed. In this study, heavy rainfall was corrected for by utilizing rainfall predictors from LENS and Radar from 2017 to 2018, as well as machine learning tools LightGBM and XGBoost. The results were analyzed using Mean Absolute Error (MAE), Normalized Peak Error (NPE), and Peak Timing Error (PTE) for rainfall corrected through machine learning. Machine learning results (i.e. using LightGBM and XGBoost) showed improvements in the overall correction of rainfall and maximum rainfall compared to LENS. For example, the MAE of case 5 was found to be 24.252 using LENS, 11.564 using LightGBM, and 11.693 using XGBoost, showing excellent error improvement in machine learning results. This rainfall correction technique can provide hydrologically meaningful rainfall information such as predictions of flooding. Future research on the interpretation of various hydrologic processes using machine learning is necessary.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.5
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• pp.719-725
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• 1986

Reed-solomon(R-S) code is very effective to coerrect both random and burst errors over a noise communication channel. However, the required hardware is very complex if the B/M algorithm was employed. Moreover, when the error correction system consists of two R-S decoder and de-interleave, the I/O data bns lines becomes 9bits because of an erasure flag bit. Thus, it increases the complexity of hardware. This paper describes the R-S decoder which consisits of a error correction section that uses a direct decoding algorithm and erasure generation section and a erasure generation section which does not use the erasure flag bit. It can be shown that the proposed R-S dicoder is very effective in reducing the size of required hardware for error correction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.2
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• pp.960-973
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• 2018

This paper presents design for error correcting algorithm of the time of flight (ToF) detection value in the light detection and ranging (LIDAR) system sensor. The walk error of ToF value is generated by change of the received signal power depending on distance between the LIDAR sensor and object. The proposed method efficiently compensates the ToF value error by the independent ToF value calculation from the received signal using both rising point and falling point. A constant error of ~0.05 m is obtained after the walk error correction while an increasing error up to ~1 m is obtained with conventional method.