• Proceedings of the KIEE Conference
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• summer
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• pp.722-724
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• 2004

Demand estimates in electric power systems have traditionally consisted of time-series analyses over long time periods. The resulting database consisted of huge amounts of data that were then analyzed to create the various coefficients used to forecast power demand. In this research, we take advantage of universally used analysis techniques analysis, but we also use easily available data-mining techniques to analyze patterns of days and special days(holidays, etc.). We then present a new method for estimating and forecasting power flow using decision tree analysis. And because analyzing the relationship between the estimate and power system ceiling Trices currently set by the Korea Power Exchange. We included power system ceiling prices in our estimate coefficients and estimate method.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.4
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• pp.652-658
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• 2016

In practical control systems differences between nominal and real systems arise from internal uncertainties and/or external disturbances. This paper presents a model-based low-order disturbance observer for a sinusoidal disturbance with unknown constant offset. By using the disturbance model of a biased harmonic signal, the proposed method can successfully estimate the biased sinusoidal disturbance with unknown amplitude and phase but known frequency. At the first stage of the observer design, a model-based disturbance observer is designed when all the system states are measurable. Next, a sufficient condition is presented for the proposed observer to estimate the sinusoidal disturbance with a minimal-order additional dynamics using only output measurement. Comparative computer simulations are performed to test the performance of the proposed method. The simulation results show the enhanced performance of the proposed disturbance observer.

• The Journal of Information Technology
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• v.3 no.1
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• pp.37-44
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• 2000

The purchasing estimate price of diamond is affected by the factors of carat, color, clarity, certificate, cut and price with the unit of $/carat. The object of this study is to obtain the linear regression model for such purchasing estimate price and to test statistically. The optimum model is the simple regression model of $^y{\;}:{\;}10^2{\;}/{\;}(-1.5575{\;}+{\;}0.3099{\;}logx){\;}+{\;}{\varepsilon}$ statistically satisfied by the lack of fit test and has the characteristics of normality, constant variance and symmetry.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.33.5-33
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• 2001

We consider here the problem of spectral estimation of multidimensional wide sense stationary (WSS) random process. A method, employing a special difference equation of correlation function, is proposed to solve the problem of multidimensional spectral estimation. In this approach, the special difference equation of correlation function is derived by modal decomposition method. Maximum likelihood estimator and Kalman filter are used to estimate the model parameters of the difference equation and the decomposed spectral residues. An algorithm is presented to estimate the multidimensional spectral density. According to the result of the simulation, these methods are feasible to estimate the spectral density of WSS process, which is realized by finite dimensional multivariable lineal system driven by white noise.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.226-234
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• 2003

Put Many researcher have made much progress in studying an estimate for fracture probability of brittle materials. However, studies of the fracture probability for the elastic-plasticity have not been made yet. An estimate method for fracture probability which is grafted onto 2-parameter criterion and statistical probability analysis is not only introduced in this study, but also applied to the simple 2dimensional model and carbon steel piping to evaluate the effect of random variable.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.4
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• pp.228-234
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• 2000

The aim of the work is to present a new method of estimating the existence of a mass unbalance and mass unbalance under a crack on a rotating shaft. This is an advanced new method for the detection of a mass unbalance and a new way to estimate the position of it under crack influence. As the first step, the shaft is physically modelled with a finite element method and the dynamic mathematical model is derived by using the Hamilton principle; thus, the system is represented by various subsystems. The equation of motion of the shaft with a mass unbalance and a crack are established by adapting the local mass unbalance and the stiffness change. this is a reference system for the given system. Based on a model for transient behavior induced from vabrations measured at the bearings, an elementary Estimator is designed to detect mass unblance on the shaft. Using the Estimator, a bank of the Estimator is established to estimate the estimate the position of the mass unbalance and arranged at a certain location on the shaft. The informations for the given system are the measurements of bearing displacements and velocity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.3
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• pp.115-121
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• 2014

HVAC&R system costs can often be one of the most expensive components, representing approximately 15% of the total construction cost for office buildings. Despite their significant importance, there is a lack of a consistent and homogeneous framework to approximate the estimate research. This research deals with the prediction methodology of HVAC&R system cost with the aim of establishing a common idea for the analysis of the construction cost estimate. Our approach deals with the concept of an HVAC&R set that is composed of subsystems. The matrix combination analysis is examined, and total 960 HVAC&R system cost estimation can be implemented to large scale office buildings.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1887-1890
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• 2003

This paper presents a three-dimensional (3D) head pose estimation algorithm using the stereo image. Given a pair of stereo image, we automatically extract several important facial feature points using the disparity map, the gabor filter and the canny edge detector. To detect the facial feature region , we propose a region dividing method using the disparity map. On the indoor head & shoulder stereo image, a face region has a larger disparity than a background. So we separate a face region from a background by a divergence of disparity. To estimate 3D head pose, we propose a 2D-3D Error Compensated-SVD (EC-SVD) algorithm. We estimate the 3D coordinates of the facial features using the correspondence of a stereo image. We can estimate the head pose of an input image using Error Compensated-SVD (EC-SVD) method. Experimental results show that the proposed method is capable of estimating pose accurately.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.69-76
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• 2003

When houses or buildings are adjacent to roads, with no effective prevention of road traffic noise, neighbors are exposed to it. It is important to understand the properties of sound propagation before taking a countermeasure against road traffic noise. It is easy to estimate the properties of sound propagation without obstacles, but very difficult and complex to estimate them with ones. The purpose of this study is to present a useful tool that can estimate the properties of sound propagation. In the beginning of this study, we investigated the attenuation of road traffic noise with two pillar buildings, and presented practical approximate calculation method, and verified that through scale model. The outcomes from this study are as follows : (1) Over second reflection sound waves can be ignored. (2) Diffraction sound waves that happen when reflection sound and first diffraction wave are projected at the wedge of other building can be ignored.

• Proceedings of the Korean Institute of Building Construction Conference
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• v.y2004m10
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• pp.15-19
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• 2004

The production of waste concrete is increased continuously by urban renewal, reconstruction, remodeling, and so on. So the positive use of recycled aggregate concrete is needed. Research for recycled aggregate concrete that use recycled aggregate from the mid-80s to solve environmental problem of aggregate insufficiency and waste concrete is consisting vigorously. However, specifications and mix design about waste concrete's use are evading use of recycled aggregate concrete yet in spot being not taken a triangular position. Therefore. it analyze existing research data for recycled aggregate concrete collection to develop strength estimate program in this research. Recycled aggregate concrete's strength estimate program if specifications and mix design about recycled aggregate concrete are taken a triangular position to foundation recycled aggregate concrete's practical use to increase judge.