• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.5
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• pp.347-356
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• 2003

Camera pose and scene geometry estimation from video sequences is widely used in various areas such as image composition. Structure and motion recovery based on the auto calibration algorithm can insert synthetic 3D objects in real but un modeled scenes and create their views from the camera positions. However, most previous methods require bundle adjustment or non linear minimization process [or more precise results. This paper presents a new auto' calibration algorithm for video sequence based on two steps: the one is key frame selection, and the other removes the key frame with inaccurate camera matrix based on an absolute quadric estimation by LMedS. In the experimental results, we have demonstrated that the proposed method can achieve a precise camera pose estimation and scene geometry recovery without bundle adjustment. In addition, virtual objects have been inserted in the real images by using the camera trajectories.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.11
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• pp.79-88
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• 1999

In this paper we address the tracking method which tracks only target object in image sequence including moving object. We use a contour tracking algorithm based on intensity and motion boundaries. The motion of the moving object contour in the image is assumed to be well describable by an affine motion model with a translation, a change in scale and a rotation. The moving object contour is represented by B-spline, the position and motion of which is estimated along the image sequence. we use pattern recognition to identify target object. In order to use linear Kalman Filters we decompose the estimation process into two filters. One is estimating the affine motion parameters and the other the shape of moving object contour. In some experiments with dial plate we show that this method enables us to obtain the robust motion estimates and tracking trajectories even in case of including obstructive object.

• Clean Technology
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• v.7 no.2
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• pp.127-132
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• 2001

The effects of activated-carbon (AC) packing length on the Pressure Swing Adsorption (PSA) performance was investigated for the hydrogen separation from the multicomponent mixture gas. Linear driving force model was used to describe mass transfer between two phase and coupled Langmuir isotherm was used for each component as a nonlinear adsorption isotherm. When two adsorbents with a different adsorption capacity were packed consecutively in one bed, it is very important to determine the packing ratio of zeolite to activated carbon affecting the purity and recovery of the product. The activated carbon packing length in adsorption tower of 120 cm was determinated by the ending point of $CO_2$ contration. The optimum length of an activated carbon layer was 65 cm for production of high-purity hydrogen.

• Journal of Digital Contents Society
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• v.10 no.4
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• pp.579-585
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• 2009

In [9], Tyrtshnikov proposed a preconditioned approach to derive a general solution from a Toeplitz linear system. Furthermore, the process of selecting a preconditioner matrix from symmetric Toeplitz matrix, which has been used in previous studies, is introduced. This research introduces a new method for finding the preconditioner in a Toeplitz system. Also, through analyzing these preconditioners, it is derived that eigenvalues of a symmetric Toeplitz are very close to eigenvalues of a new preconditioner for T. It is shown that if the spectrum of the preconditioned system $C_0^{-1}T$ is clustered around 1, then the convergence rate of the preconditioned system is superlinear. From these results, it is determined to get the superliner at the convergence rate by our good preconditioner $C_0$. Moreover, an advantage is driven by increasing various applications i. e. image processing, signal processing, etc. in this study from the proposed preconditioners for Toeplitz matrices. Another characteristic, which this research holds, is that the preconditioner retains the properties of the Toeplitz matrix.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.3
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• pp.1-8
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• 2001

Seismic design forces for bridge components may be determined by modifying elastic member forces of design earthquakes using appropriate response modification factors according to the national design code of bridges Modeling technique of pile foundation system is one of the important parameters which greatly affects the results in the process of the elastic seismic analysis of a bridge system with pile foundation. In this paper, a approximate and simplified modeling technique of a pile foundation system for the practical purposes is presented. The modeling technique is based on the stiffnesses of pile foundation during earthquake. The horizontal stiffnesses are determined from the resistance-deflection curves derived from the results of dynamic field tests using cyclic loads and the vertical stiffness includes the effects of the end bearing capacities and side friction of piles as well as the pile compliances under the expected vertical load level. The applicability of the proposed technique has been validated through the some example bridge analyses.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.25-30
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• 2016

It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

• Food Science and Preservation
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• v.12 no.2
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• pp.151-155
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• 2005

General problems on the quality in circulation process of Kochujang are fluidity, separated water at upper layer, and color change to dark-brown. Rice powders, glutinous rice powder and gelatinized rice powder, gelatinized glutinous rice powder were applied for solving such problems to Kochujang. Relationship between blending ratio of com syrup and fluidity had a linear correlation. Water separation in Kochujang was prevented by addition of gelatinized cereal powders, and gelatinized glufinous rice powder was most effective. Optimal amount of gelatinized glutinous rice powder was $0.5\~1.0\%$ (w/w).

• School Mathematics
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• v.17 no.3
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• pp.447-467
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• 2015

The purpose of this study is to examine how the learning experience understanding degree and radian as the measurement of arc affects the conceptual understanding of radian and measuring angle. For this purpose, we investigated pre-service teachers' understanding about measurement of angle using a length of arc, and then conducted a teaching experiment with two middle school students. The results of analyzing pre-service teachers' and students' response are as follows. Students' experience interpreting the concept of degree into measurement of arc had a positive effect on understanding of radian and students' learning process in which they got measurement of angle as measurement of arc enabled conceptual understanding of 'linear measuring'. Also a circle context and a strategy dividing by arc operated as effective strategies for solving various problems about an angle. Finally, we confirmed that providing direct manipulative activities as a chance to explore relationships between an angle and arc measure can help students' conceptual understanding of measuring angle.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.285-291
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• 2011

The error motion of a machine tool spindle directly affects the surface errors of machined parts. The error motions of the spindle are not desired errors in the three linear direction motions and two rotating motions. Those are usually due to the imperfect of bearings, stiffness of spindle, assembly errors, external force or unbalance of rotors. The error motions of the spindle have been needed to be decreased to desired goal of spindle's performance. The level of error motion is needed to be estimated during the design and assembly process of the spindle. In this paper, the estimation method for the five degree of freedom (5 D.O.F) error motions of the spindle is suggested. To estimate the error motions of the spindle, waviness of shaft and bearings, external force model was used as input data. And, the estimation models are considering geometric relationship and force equilibrium of the five degree of the freedom. To calculate error motions of the spindle, not only imperfection of the shaft, bearings, such as rolling element bearing, hydrostatic bearing, and aerostatic bearing, but also driving elements such as worm, pulley, and direct driving motor systems, were considered.

• International Journal of Highway Engineering
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• v.16 no.6
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• pp.95-104
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• 2014

PURPOSES : The purpose of this study is to evaluate the degree of restraint (DOR) of longitudinal steel at continuously reinforced concrete pavement (CRCP) against environmental loadings. METHODS : To measure the longitudinal steel strain, 3-electrical resistance and self-temperature compensation gauges were installed to CRCP test section (thickness = 250mm, steel ratio = 0.7%) and continuously measured 10 min. intervals during 259 days. In order to properly analyze the steel strains first, temperature compensation process has been conducted. Secondly, measured steel strains were divided into 12 phases with different events such as before paving, during concrete hardening, and after first cracking, etc. RESULTS : Thermal strain rate (TSR) concept is defined as the linear strain variations with temperature changes and restraints rate of longitudinal steel against environmental loadings (especially thermal loading) with different cases is defined as degree of restraint(DOR). New concept of DOR could be indirect indicator of crack width behaviors of CRCP. CONCLUSIONS : Before paving, DOR of longitudinal steel is almost same at the coefficient of thermal expansion of steel ($12.44m/m/^{\circ}C$) because of no restraint boundary condition. After concrete pouring, DOR is gradually changed into -1 due to concrete stiffness developing with hydration. After first cracking at crack induced area, values of DOR are around -3~-5. The negative DOR stands for the crack width behavior instead of steel strain behavior. During winter season, DOR reached to -5.77 as the highest, but spring this values gradually reduced as -1.7 as the lowest. Based on this observation, we can presume crack width decreased over time within the time frame of this study. This finding is not consistent with the current theory on crack width variations over time, so further study is necessary to identify the causes of crack width reducing. One of the reasons could be related to concrete stress re-distribution and stress relaxation.