• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.454-457
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• 2006

This study presents a strut-and-tie model for the development of headed bars in an exterior beam-column joint with transverse reinforcements. The tensile force of a headed bar is considered to be developed by head bearing together with bond along a bonded length as a partial embedment length. The model requires construction of struts with biaxially compressed nodal zones for head bearing and fan-shaped stress fields against neighboring nodal zones for bond stresses along the bonded length. Due to the existence of transverse reinforcements, the fan-shaped stress fields are divided into direct and indirect fan-shaped stress fields. A required development length and head size of a headed bar can be optimally designed by adjusting a proportion between a bond contribution and bearing contribution.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.11
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• pp.479-486
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• 1986

It is necessary to consider a rotor movement in dynamic analysis on the flux distribution of electric machinery by FEM. Therefore, if air-gap domain was subdivided into triangular elements, computation results contain errors due to variation of element shape in air-gap because the nodal points corresponding to the rotor are displaced in analyzing domain for the time difference. In order to reduce this errors, the paper presents a application of a Macro Air-gap Element that interpolation function is obtained analytically and a means to join it with linear triangular elements in the rotating machine or in the linear machine. At the end of paper, setting up analytic domain model, it compares analytic solution with the computation results of Macro Air-gap Element appliction and that of linear triangular element subdivision only to each cases of nodal displacement. And it carries out that errors due to variation of element shape are reduced effectively by application of a Macro air-gap element.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.8
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• pp.374-379
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• 2000

The nodal marginal cost and the congestion charge are used as the econimic signals for the electricity price and new invetments in deregulated power systems. In this paper, the nodal marginal cost and the congestion charge are calculated by using the shadow prices resulted from the calculation of Optimal Power Flow(OPF). Linearization of inequality constraints and piecewise linear cost functions make an OPF problem LP-based forms. In order to use the shadow price, the Interior Point(IP) algorithm is applied as a solution technique to the formulation. This paper proposes an algorithm to determine efficients initial points which are guaranteed to be interior points.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.425-427
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• 2002

In a deregulated power market, a load model considered the characteristics of electric consumers is required and the congestion management of transmission lines should be resolved in a point of economic benefits. It is essential that the optimal power flow algorithm is applied to manage transmission line congestion. Therefore, in this paper, we implement the optimal power flow with object function of social welfare maximization based linear programming and analysis the nodal prices for generations and loads through a numerical study.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.438-440
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• 2002

In deregulated power market, transmission pricing methodology should maintain non-discrimination amongst all participants while ensure that TRANSCOs recover their revenue requirements. The proposed transmission pricing methodology for Korea needs cost allocation ratios, such as allocation ratio of physical transport to network security and that of generators to loads. In this paper, we studied the nodal transmission price determined by the cost allocation factors and its influence on GENCOs and DISTCOs.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.705-710
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• 2003

Many papers have studied computer simulations of elastic bodies undergoing large deflections and large deformations. But there have not been many attempts to check the validity of the numerical formulations because the simulation results could not be matched without correct input data such as material properties and damping effects. In this paper, these values are obtained from real experiment with a high-speed camera and a data acquisition system. The simulation results with the absolute nodal coordinate formulation (ANCF) are compared with the results of real experiments. Two examples, a thin cantilever beam and a thin plate, are studied to verify whether the simulation results are well matched to experimental results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.213-219
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• 2001

This paper deals with the free vibration of two identical circular plates coupled with a bounded fluid. An analytical method based on the [mite Fourier-Bessel series expansion and Rayleigh-Ritz method is suggested. In the theory, it is assumed that the ideal fluid is filled in a rigid cylindrical container and the two plates are clamped along the plate edges. The proposed method is verified by the finite element analysis using commercial software with a good accuracy. Two transverse vibration modes, namely in-phase and out-of-phase, are observed alternately in the fluid-coupled system when the number of nodal circles increases for the fixed nodal diameter. The effect of gap between the plates on the fluid-coupled natural frequency is also investigated.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.514-519
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• 2006

This paper presents a new nonlinear analysis algorithm which uses the equivalent nodal load for the element stiffness. The equivalent nodal load represents the influence of the stiffness change such as the addition of elements, the deletion of elements, and/or the partial change of element stiffness. The nonlinear analysis of structures using the equivalent load improves the efficiency very much because the inverse of the structural stiffness matrix, which needs a large amount of computation to calculate, is reused in each loading step. In this paper, the concept of nonlinear analysis using the equivalent load for the element stiffness is described and some numerical examples are provided to verify it.

• Journal of KSNVE
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• v.8 no.4
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• pp.623-631
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• 1998

The free vibration analyses of the isotropic and composite(CFRP, GFRP) rectangular plates with point supports at the free edge and middle position are performed. The natural frequencies and nodal patterns of plates with point supports are experimentally determined by impact testing using an impact hammer. To compare and verify these experimental results, the finite element analysis is also carried out. The effect of the point support position, the number of point supports, and the anisotropic parameters on the natural frequencies and nodal patterns of cantilevered rectangular plates are investigated.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.298-299
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• 2008

In this paper, supposed that can measure power quality of bus and can calculate this cost in case electric charges about customer are imposed by each bus. When reflected this in system planning, expected cost proposed following method through sample system. We calculated the nodal cost by OPF(optimal power flow) in system and the drop numbers that happen during year of loads utilizing VSCC. Also calculated BPQC using the disruption numbers. As a result, calculated bus total cost including power quality cost through case study.