• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.40-46
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• 2013

Automatic swing door for an automotive application is considered. The equation of motion for a driver side swing door is introduced and gravity cancellation control scheme is adapted. The control scheme supposed to cancel the moment due to the tilt of the car. A speed control is suggested for door operation automation but the output of the speed control is not suppose to be precise as for the manufacturing system control. In the frame of the velocity control of the door, feedback linearization was applied for collision detection. The collision detection performance is satisfactory. The estimate of the magnitude of disturbance due to the collision is close to the actual magnitude of disturbance. Simulation study has been performed to gain insight into the system behavior. Also real test on the prototype hardware has been performed for verification purpose.

• Earthquakes and Structures
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• v.26 no.2
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• pp.117-130
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• 2024

Probabilistic model of seismic demand is the main tool used for seismic demand estimation, which is a fundamental component of the new performance-based design method. This model seeks to mathematically relate the seismic demand parameter and the ground motion intensity measure. This study is intended to use Bayesian analysis to evaluate the accuracy of the seismic demand estimation of Steel moment resisting frames (SMRFs) through a completely Bayesian method in statistical calculations. In this study, two types of intensity measures (earthquake intensity-related indices such as magnitude and distance and intensity indices related to ground motion and spectral response including peak ground acceleration (PGA) and spectral acceleration (SA)) have been used to form the models. In addition, an extensive database consisting of sixty accelerograms was used for time-series analysis, and the target structures included five SMRFs of three, six, nine, twelve and fifteen stories. The results of this study showed that for low-rise frames, first mode spectral acceleration index is sufficient to accurately estimate demand. However, for high-rise frames, two parameters should be used to increase the accuracy. In addition, adding the product of the square of earthquake magnitude multiplied by distance to the model can significantly increase the accuracy of seismic demand estimation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.3
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• pp.255-259
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• 1988

The distributing current is calculated on the infinit plane mattaric grattings for the TM waves. The matrix is larger, when the moment method is applied this structure. So, the moment method of this case is required large memory and long CPU times. Those boundary condition and the scattering formura are transformed into spectal domain. Taking account of the peridic structure, this formular is changed in a series form by using the Flouquet mode. By making a suitable basis function, this equation is expreseed matrix form. So the distributing current on the mattaric strip is able to caculate by using this equation. We calculate magnitude of the distributing current for varing these spaces, widthes and an angle of incident waves.

• Journal of Advanced Navigation Technology
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• v.18 no.1
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• pp.78-83
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• 2014

In this paper, the solutions of TM (transverse magnetic) scattering problems by perfectly conducting strip grating on two dielectric layers are analyzed by applying the FGMM (Fourier Galerkin moment method) as a numerical method. For the TM scattering problem, the induced surface current density is expected to the very high value at both edges of the strip, then the induced surface current density on the strip is expanded in a series of the multiplication of the functions of appropriate edge boundary condition and the Chebyshev polynomials of the first kind. The numerical results are obtained for the magnitude of induced current density, the normalized reflected power and transmitted power. The numerical results using proposed functions were improved the convergence faster than existing exponential functions, and the numerical results shown the good agreement compared to those of the existing papers.

• Journal of Life Science
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• v.20 no.11
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• pp.1704-1710
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• 2010

The purpose of this study was to describe the biomechanical characteristics of stroke patients. These characteristics were obtained during walking on a Zebris system, cinematography system and EMG system. Seven female stroke patients participated in this study. The magnitude of the profiles (joint peak angle, joint peak moments, foot pressure COP, EMG data) correlated with rehabilitation training duration using t-test. The significance level selected for this study was p<0.05, t-test. Joint analysis identified significant differences in hip joint peak angle and hip joint peak moment. Foot pressure verified significant differences in gait line length of COP. The EMG signal proved significant differences in rectus femoris and vastus lateralis.

• Geotechnical Engineering
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• v.3 no.3
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• pp.21-30
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• 1987

Some methods are presented to estimate the ultimate lateral resistance of single active piles subjected to lateral loads above the ground surface, considering the lateral soil reaction, the pile length and the fixity condition of a pile head. The lateral soil reaction acting on a single active pile embedded in soil due to pile movement can be estimated by use of a theoretical equation which is derived by considering especially the plastic state of ground surrounding the pile and the pile- section shape. The piles are named short or long depending upon the relative magnitude of the induced bending moment to the yielding moment. As for the fixity condition of a pile head, the free head and the unrotated head are considered. Comparison with other experimental results gives that the calculated ultimate lateral resistance obtained by the author's theory is closer to experimental results than the one obtained by Brom's theory.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.309-313
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• 2015

If the present universe is slightly open then pre-inflation curvature would appear as a cosmic dark-flow component of the CMB dipole moment. We summarize current cosmological constraints on this cosmic dark flow and analyze the possible constraints on parameters characterizing the pre-inflating universe in an inflation model with a present-day very slightly open ${\Lambda}CDM$ cosmology. We employ an analytic model to show that for a broad class of inflation-generating effective potentials, the simple requirement that the observed dipole moment represents the pre-inflation curvature as it enters the horizon allows one to set upper and lower limits on the magnitude and wavelength scale of pre-inflation fluctuations in the inflaton field and the curvature parameter of the pre-inflation universe, as a function of the fraction of the total initial energy density in the inflaton field. We estimate that if the current CMB dipole is a universal dark flow (or if it is near the upper limit set by the Planck Collaboration) then the present constraints on ${\Lambda}CDM$ cosmological parameters imply rather small curvature ${\Omega}_k{\sim}0.1$ for the pre-inflating universe for a broad range of the fraction of the total energy in the inflaton field at the onset of inflation. Such small pre-inflation curvature might be indicative of open-inflation models in which there are two epochs of inflation.

• Journal of the Korean Magnetics Society
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• v.14 no.4
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• pp.115-119
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• 2004

We measured in-plane 2 dimensional magnetization vector using two pick-up coil sets and investigate the relationship between magnetization vector and anisotropic magnetoresistance. We can determine magnetization vector by measuring magnetic moment in x and y direction simultaneously. As the uniaxial magnetic anisotropy of permalloy film increases, magnetoresistance approaches the expectation which is calculated from the angle between current vector and magnetization vector. Magnetoresistance ratio is linearly proportional to the y moment magnitude which is parallel to the current direction.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.74-81
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• 2009

In this study, the seismic performance of RC school buildings which were not designed according to earthquake-resistance design code were evaluated by using response spectrum and push-over analyses. The torsional amplification effect due to plan irregularity is considered and then the efficiency of seismic retrofitting methods such as RC shear wall, steel frame, RC frame and PC wing wall was investigated. The analysis result indicate that the inter-story drift concentrated in the first floor and most plastic hinge forms at the column of the first story. Among the retrofitting methods, the PC wing wall has the highest seismic performance in strength and story drift aspect. Especially, it can make building ductile behavior due to the concentrated inter-story drift at the first column hinge is distributed overall stories. The axial force, shear force and moment magnitude of existing elements significantly decreased after retrofitting. However, the axial and shear force of the elements connected to the additional retrofitting elements increased, and especially the boundary columns at the end of the retrofitting shear wall should be reinforced for assuring the enhancement of seismic performance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.3
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• pp.77-82
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• 2023

In this paper, TM(tranverse magnetic) electromagnetic scattering problems for resitive strip grating between grounded double dielectric layers are analyzed by using the FGMM(fourier galerkin moment method) and PMM(point matching method) known as a numerical method of electromagnetic field. The boundary conditions are applied to obtain the unknown field coefficients, the resistive boundary condition is applied to analysis of resistive strip. Overall, when the unoform resistivity decreased, the magnitude of the current density induced in the resistive strip increased, and the reflected power also increased. Also, as the thickness and relative permittivity of the double dielectric layers increased, the overall reflected power increased. The numerical results obtained by using the numerical methods of FGMM and PMM to the structure proposed in this paper agree very well.