• Steel and Composite Structures
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• v.9 no.5
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• pp.473-497
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• 2009

For the spatially coupled free vibration analysis of composite box beams resting on elastic foundation under the axial force, the exact solutions are presented by using the power series method based on the homogeneous form of simultaneous ordinary differential equations. The general vibrational theory for the composite box beam with arbitrary lamination is developed by introducing Vlasov°Øs assumption. Next, the equations of motion and force-displacement relationships are derived from the energy principle and explicit expressions for displacement parameters are presented based on power series expansions of displacement components. Finally, the dynamic stiffness matrix is calculated using force-displacement relationships. In addition, the finite element model based on the classical Hermitian interpolation polynomial is presented. To show the performances of the proposed dynamic stiffness matrix of composite box beam, the numerical solutions are presented and compared with the finite element solutions using the Hermitian beam elements and the results from other researchers. Particularly, the effects of the fiber orientation, the axial force, the elastic foundation, and the boundary condition on the vibrational behavior of composite box beam are investigated parametrically. Also the emphasis is given in showing the phenomenon of vibration mode change.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.113-116
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• 2004

Output power of a photovoltaic system changes continuously as it strongly depends on the weather condition(isolation and temperature). Therefore, it is necessary the theoretical model realizes the electrical output characteristics of solar cell. Of several theoretical models for real solar cell, both parametric model and interpolation model are used widely. In this paper, we have propose a improved model of solar cell using its output characteristics that can be extended to calculate the rear solar cell characteristics at various temperatures and insolation. And more, the theoretical research of several models of solar cell using simulation analysis.

• Electrical & Electronic Materials
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• v.9 no.8
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• pp.783-788
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• 1996

In this paper, the high-$T_c$ , superconductor (HTS) microstrip patch antenna which is directly coupled to a microstrip transmission line is designed and the numerical solution which evaluate near electromagnetic field of HTS antenna is presented. This solution uses the interpolation function with the vector edge triangular element. The advantage of this element is the elimination of spurious solutions attributed to the lack of enforcement of the divergence condition. The results of this method have a good agreement with $TM_10$ mode in HTS microstrip patch antenna and show that the computation of resonant length considering the fringing capacitance effect at radiating edge are proper.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.293-299
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• 2001

Since the previous cut-and-try design algorithm require much cost and time, it has recently been concerned the automatic design technique using the CFD and optimum design algorithm. In this study, the Navier-Stokes equations is solved to consider the more detail viscous flow informations of cascade interaction and O-H multiblock grid system is generated to impose an accurate boundary condition. The cubic-spline interpolation is applied to handle a relative motion of a rotor to the stator. To validate present procedure, the time averaged aerodynamic loads are compared with experiment and good agreement obtained. Once the N-S equations have been solved, the computed aerodynamic loads may be used to computed the sensitivities of the aerodynamic objective function. The Modified Method of feasible Direction(MMFD) is usef to compute the

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.10
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• pp.821-827
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• 2003

The so-called boundary node method (or NDIF method) that was developed by the authors has been extended for free vibration analysis of arbitrarily shaped plates with free edges. Since the proposed method requires no interpolation functions. no integration Procedure is needed on boundary edges of the plates and only a small amount of numerical calculation is involved, compared with FEM and BEM. In order to explain tile reason why spurious eigenvalues are generated when the NDIF method is applied to free plates, the NDIF method has been considered for free vibration analysis of both a fixed string and a free beam. Finally, verification examples show that natural frequencies obtained by the present method agree well with those given by an exact method or a numerical method (ANSYS).

• International Journal of CAD/CAM
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• v.6 no.1
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• pp.149-156
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• 2006

This paper presents a novel approach for constructing a piecewise triangular cubic polynomial surface with $C^1$ continuity around a common corner vertex. A $C^1$ continuity condition between two cubic triangular patches is first derived using mixed directional derivatives. An approach for constructing a surface with $C^1$ continuity around a corner is then developed. Our approach is easy and fast with the virtue of cubic reproduction, local shape controllability, $C^2$ continuous at the corner vertex. Some experimental results are presented to show the applicability and flexibility of the approach.

• Journal of Mechanical Science and Technology
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• v.18 no.10
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• pp.1747-1754
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• 2004

In this study, a new harmonic axisymmetric thick shell element for static and dynamic analyses is proposed. The newly proposed element considering shear strain is based on a modified Hellinger-Reissner variational principle, and introduces additional nodeless degrees for displacement field interpolation in order to enhance numerical performance. The stress parameters selected via the field-consistency concept. are very important in formulating a trouble-free hybrid-mixed elements. For computational efficiency, the stress parameters are eliminated by the stationary condition and then the nodeless degrees are condensed out by the dynamic reduction. Several numerical examples confirm that the present element shows improved efficiency and yields very accurate results for static and vibration analyses.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.891-894
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• 2001

본 논문은 서로 다른 얼굴이미지 사이의 얼굴매칭기법의 새로운 방법인 TBCC(T-Block constraints Condition)얼굴매칭기법을 제안한다. 본 논문에서 제안하는 방법은 T영역안의 이목구비에다가 제어영역을 두고, T영역과 제어영역들을 분리하여 2개의 영상으로 각각 만든 다음에 각각의 correspondence가 있는 영상끼리 와핑(Warping)을 한 후에, 제어영역들은 2단계구조를 가진 계층적인 선형조합(Linear Combination)모델에 적용시켜 최적의 위치를 찾아낸 후에, T영역에 와핑시켜서 하나의 합성사진을 만들어 낸다. 합성사진에서 피부색이 다른 문제는 정규분표를 이용한 크로스디졸브(Cross-Dissolve)방법인 이미지프로세싱 기법을 새롭게 적용하며, 그리고, T모양의 자국이 남는 것은 본 논문에서 제안하는 T-Block Color Interpolation방법을 적용해서 해결한다.

• Journal of the Chungcheong Mathematical Society
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• v.1 no.1
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• pp.27-32
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• 1988

In this paper, we study the multipliers of $A^p_q$ into $L^{p^{\prime}}$ when 0 < p' < p. For this purpose, we study the condition on the measure ${\mu}$ satisfying $A^p_q{\subset}A^{p^{\prime}}(d{\mu})$. It turns out that the quotient $k_q={\mu}/v_q$ over hyperbolic ball of radius less than 1 belongs to $L^s_q$, where $\frac{1}{s}+\frac{p^{\prime}}{p}=1$. For the proof, we replace the norm of $k_q$ by the Riemann sum, and then use a result of interpolation theory.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.4
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• pp.69-76
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• 1994

Thermal elasto-plastic analysis of axi-symmetric body by the finite element method is presented in this paper for analyzing the process of upset forming of circular section extruded bar. The example of calculation for upset forming of Nimonic extruded bar is also presented. It is shown that remeshing of quadrilateral finite element is necessary because the very highly distorted element by plastic deformation disturbs the calculation. Calculated values for nodal points in new mesh are obtained from nodal points of old mesh by linear interpolation method. The experimental results are compared with calculated values. The appearance of upsetupset forming obtained by experimental method is very similar to that obtained by calculations. So, it is proved that the thermal elasto-plastic analysis of axi-symmetric body by the finite element method is very useful for finding the optimum upsetting condition.