• Journal of Institute of Control, Robotics and Systems
• /
• v.8 no.6
• /
• pp.524-532
• /
• 2002

This paper presents a new in-flight alignment method for an SDINS under large initial heading error. To handle large heading error, a new attitude error model is introduced. The attitude errors are divided into heading error and leveling errors using a newly defined horizontal frame. Some navigation error dynamic models are derived from the attitude error model for indirect feedback filtering of the in-flight alignment system. A Kalman filter with Position measurement is designed to estimate navigation errors as the indirect feedback filter Simulation results show that the proposed in-flight alignment method reduces the heading error very quickly from more than 40deg to about 5deg so as to apply a refined navigation filter. The total alignment process including leveling mode and navigation mode in addition to the proposed one allows large initial values not only in heading error but also in leveling errors.

• Journal of Korean Society for Quality Management
• /
• v.23 no.3
• /
• pp.57-68
• /
• 1995

In this paper, we consider possibility that the multiple errors occur in each testing stage. At present, software reliability modeling is considered as a part of software reliability quality assurance in software engineering. However they dealt with the software growth model for the single error debugging at each testing stage until now. Hence it is necessary to study software reliability with multiple errors debugging. Therefore we propose software reliability growth modeling and estimate the parameters in the proposed software reliability growth model for the multiple errors debugging at each testing stage.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.25 no.6_1
• /
• pp.537-543
• /
• 2007

Since the GPS absolute positioning with pseudorange measurements can significantly be affected by the observation error, the time series analysis of the GPS receiver clock errors was performed in this study. From the estimated receiver clock errors, the time series model is generated, and constrained back in the absolute positioning process. One of the CORS (Continuously Operating Reference Stations) network is used to analyze the behavior of the receiver clock. The dominant part of the model is the linear trend during 24 hours, and the seasonal component is also estimated. After constraining the modeled receiver clock errors, the estimated position error compared to the published coordinates is improved from ${\pm}11.4\;m\;to\;{\pm}9.5\;m$ in 3D RMS.

• Journal of Institute of Control, Robotics and Systems
• /
• v.8 no.2
• /
• pp.167-177
• /
• 2002

In Strapdown Inertial Navigation System(SDINS), error models based on previously proposed conversion equations between the attitude errors, are only valid in case the attitude errors are small. The SDINS error models have been independently studied according to the definition of the reference frame and of the attitude error. The conversion equations between the attitude errors applicable to SDINS with large attitude errors are newly derived. Lyapunov transformation matrices are also derived from the obtained results. Furthermore the general method, which is independent of the attitude error and the reference frame to derive SDINS error model, is proposed using the Lyapunov transformation.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.30 no.3
• /
• pp.95-105
• /
• 1988

This study refers to the development of a hydrologic model simulating daily inflow and release rates for irrigation reservoirs. A daily - based model is needed for adequate operation of an irrigation reservoir sufficing the water demand for paddy fields which is closely related to meteorological conditions. And the objective or this study is to develop a Daily Irrigation Reservoir Operation Model(DIROM) combining the inflow and the release models which depicts the daily water level fluctuations of an irrigation reservoir, and to evaluate the applicability of the model. DIROM was applied to four reservoirs and daily water levels were simulated and compared to the observed data. The model behaviour was also compared with that of a ten - day based model, Reservoir Operation Study(ROS) which has been applied for determining the design capacity of reservoirs. Various combinations of measured and simulated inflow and release rates for tested reservoirs were used to define the daily water level fluctuations. Simulated release rates and measured inflow data resulted in larger errors, and simulated inflow and release rates produced the smallest errors in water level comparison. Two resevoir operation models, DIROM and ROS were applied to the same reservoir and the simulation results compared. The computational errors of DIROM ware smaller than those of ROS, and DIROM was more sensitive to meteorological conditions. DIROM demonstrated its potenial applicability in water management and operation.

• Journal of Korean Academy of Fundamentals of Nursing
• /
• v.22 no.2
• /
• pp.180-189
• /
• 2015

Purpose: The purpose of this study was to identify the types of errors that occurred and were recovered in a simulated transfusion scenario by nursing students. Methods: Twenty-eight teams of a total of 89 nursing students participated in a transfusion simulation using a high fidelity simulator. Data were collected by observing rule based errors and built in errors recovered according to the framework of Eindhoven model. Reflective journaling was used to identify perceived safety-threatening errors and commitment to improvement. Data were analyzed using descriptive statistics. Results: All teams committed the rule based errors in the scenario. The most common errors occurred in the coordination category related to communication with physician. Most of students perceived the transfusion reaction as a safety-threatening error. Conclusion: The findings indicate that students lack patient safety competence. The simulation training to decrease errors and improve safe practice provides nursing students with an effective strategy to develop patient safety competence.

• Journal of Korean Society for Quality Management
• /
• v.41 no.4
• /
• pp.673-681
• /
• 2013

Purpose: The purpose of this study is to investigate the design optimization modeling of screening procedures based on the assessment of misclassification errors. Methods: Misclassification errors due to measurement variability are derived for normally distributed quality characteristics. Further, an optimization model for ensuring the level of outgoing quality is proposed and demonstrated through an illustrative example. Results: It is shown that two types of misclassification errors (i.e., false acceptance and false rejection) may be properly compromised through an analytical assessment of measurement errors and an optimization modeling. It is also discussed that a variety of optimization modeling may be enabled based on the derivation of measurement errors. Conclusion: It may be concluded that the design of screening inspection may further be facilitated by including the effect of measurement errors on the performance of screening inspection procedure.

• Communications for Statistical Applications and Methods
• /
• v.29 no.5
• /
• pp.533-545
• /
• 2022

Collection of data on several variables, especially in the field of medicine, results in the problem of measurement errors. The presence of such measurement errors may influence the outcomes or estimates of the parameter in the model. In classification scenario, the presence of measurement errors will affect the intrinsic cum summary measures of Receiver Operating Characteristic (ROC) curve. In the context of ROC curve, only a few researchers have attempted to study the problem of measurement errors in estimating the area under their respective ROC curves in the framework of univariate setup. In this paper, we work on the estimation of area under the multivariate ROC curve in the presence of measurement errors. The proposed work is supported with a real dataset and simulation studies. Results show that the proposed bias-corrected estimator helps in correcting the AUC with minimum bias and minimum mean square error.

• Journal of the Korean Statistical Society
• /
• v.36 no.2
• /
• pp.183-200
• /
• 2007

We consider a nonlinear autoregressive moving average model with nonlinear GARCH errors, and find sufficient conditions for the existence of a strictly stationary solution of three related time series equations. We also consider a geometric ergodicity and functional central limit theorem for a nonlinear autoregressive model with nonlinear ARCH errors. The given model includes broad classes of nonlinear models. New results are obtained, and known results are shown to emerge as special cases.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10a
• /
• pp.161-166
• /
• 1990

In this paper, Proposed the robust controller for robot manipulator plus actuator with dynamic parameter uncertainties. In general, errors and uncertainties system parameters exist more or less between the actual system and mathematical model. To reduce these trems, used Lyapunov stability theorem. The performance of the controller is evaluated for the three degree of freedom robot manipulator plus actuator model with uncertainties of parameters and model errors.