• Journal of Industrial Technology
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• v.17
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• pp.43-50
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• 1997

Local administration is closely related with intention of residents. Especially, a plan item is closely related with life of residents. Therefore, it has to be logical and objective solution for opinion convergence. Decision of opinion has to be in a triangular position standard and stand in a trio of criteria in standard. But, opinion convergence of residents very difficult. Recently, the technique of GIS presents method for oponion convergence with logical and objective and scientifically solution. And, this study present method for decision of intention to a complex element with GRID and NETWORK techniques of GIS. This study present optimun site of constructure with the GIS technique in consideration of a side face of transportation, technical, social economy and environments.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.529-534
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• 1998

To find out an adequate failure criterion in two-dimensional linear elastic crack problems, finite element programs, SED, which determine stress intensity factors $K_I, K_{II}$, crack angle and peak load by the minimum strain energy density failure criterion were developed. In this program, the conventional quadratic isoparametric elements were used in all regions except the crack tip zone where triangular singular elements with 6 nodes were used. The results of SED were compared with the results of those which followed by the maximum circumferential tensile stress criteria and those by the maximum energy release rate criteria and those by Jenq and Shah`s experiments of the same geometry and material properties. The maximum energy release rate criteria were better close to those of the Jenq and Shah`s experiments than the maximum circumferential tensile stress criteria and the minimum strain energy density criteria.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.130-133
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• 2001

Recent days composite bridge deck is gaining attraction due to many advantages such as light weight, high strength, corrosion resistance, and high durability. In this study, composite sandwich deck models of hat, box, and triangular section type were fabricated by VARTM process. For those models, three point flexural test was carried out both in strong and weak axis. The experimental results are compared with each other to determine efficient section type. Also finite element analysis was performed to verify analysis model. It is demonstrated that the results of numerical analysis agree well with experimental results.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.568-572
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• 1998

This paper defines Fuzzy Logic Units(FLUs) which are piece wise finite elements in multidimension Euclidean space, and redefines triangular membership functions which are different from those defined in traditional literature. By analyzing FLUs, this paper gives a constructive method of fuzzy rules in fuzzy logic systems based on finite element method. The simulation results of single machine to infinite bus system show the effectiveness of the proposed method in this paper.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.3 s.180
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• pp.39-46
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• 2006

In this work a dynamic cutting force model in ball end milling of inclined surface is introduced. To represent the complex cutting geometry in ball end milling of inclined surface, workpiece is modeled with Z-map method and cutting edges are divided into finite cutting edge elements. As tool rotates and vibrates, a finite cutting edge element makes two triangular sub-patches. Using the number of nodes in workpiece which are in the interior of sub-patches, instant average uncut chip thickness is derived. Instant dynamic cutting forces are computed with the chip thickness and cutting coefficients. The deformation of cutting tool induced by cutting farces is also computed. With iterative computation of these procedures, a dynamic cutting force model is generated. The model is verified with several experiments.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.769-777
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• 1998

That main purpose of this paper is to clarify the effects of geometrically initial imperfection on the buckling characteristics of the pin-jointed single-layer lattice domes with triangular network. Additionally, this study is to get the data that is to formulate the general buckling-strength equation taking geometrically initial imperfection into consideration. Analysis is undertaken by using the frame analysis method which is based on the finite element method dealing with geometrically nonlinear problem.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.702_703
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• 2009

Electric Power Steering(EPS) system is superior to conventional Hydraulic Power Steering(HPS) system in aspect of fuel economy and environmental concerns. The EPS system consists of torque sensor, electric motor, ECU(Electric Control Unit), gears and etc. Among the elements, the torque sensor is one of the core technologies of which output signal is used for main input of EPS controller. Usually, the torque sensor has used torsion bar to transform torsion angle into torque. The torsion angle of both ends of a torsion bar is measured by a contact variable resistor. In this paper, the sensor is accurately analyzed using 3D finite element method and its characteristics with respect to four different shapes of the stator teeth are compared. The four shapes are rectangular, triangular, trapezoidal and circular type.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2165-2172
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• 1995

Optimization of mesh discretization has been proposed to improve the accuracy of limit analysis solution of collapse load by using the Rigid Body Spring Model(R. B. S. M) under the plane strain condition. Moreover, the fracture behaviour of materials was investigated by employing the fracture mechanism of a spring connecting the triangular rigid body element. It has been clarified that the collapse load and the geometry of slip boundary for optimized mesh discretization were close to those of the slip line solution. Further, the wedge-shaped fracture of a cylinder under a lateral load and the central fracture of a strip in the drawing process were well simulated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.2
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• pp.153-160
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• 1983

The flows in an axial flow turbomachine are calculated numerically in the two sets of flow surfaces of H-S and B-B surfaces assuming that the flow is axisymmetric. The calculation is performed by regarding the governing equations as the quasi-Poisson's equations and using the finite element method for the flow regions divided into triangular elements. The results of numerical calculation agree comparatively well with the experimental results and it has been found that the distribution of an axial velocity component at the rotor exit is not necessarily uniform under the influences of the inlet guide vanes and the front shape of the hub even if the rotor is designed by the free-vortex theory. Also it has been found that the existence of the optimum value of the blade number can be estimated from the results of calculation of deviation angles at rotor exit if we consider the viscous flow-loss, and that the flows of B-B surfaces are affected very sensitively by the degree of satisfaction of Kutta condition.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.5 no.1
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• pp.55-78
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• 2001

Given the anisotropic Poisson equation $-{\nabla}{\cdot}{\mathcal{K}}{\nabla}p=f$, one can convert it into a system of two first order PDEs: the Darcy law for the flux $u=-{\mathcal{K}{\nabla}p$ and conservation of mass ${\nabla}{\cdot}u=f$. A very natural mixed finite volume method for this system is to seek the pressure in the nonconforming P1 space and the Darcy velocity in the lowest order Raviart-Thomas space. The equations for these variables are obtained by integrating the two first order systems over the triangular volumes. In this paper we show that such a method is really a standard finite element method with local recovery of the flux in disguise. As a consequence, we compare two approaches in analyzing finite volume methods (FVM) and shed light on the proper way of analyzing non co-volume type of FVM. Numerical results for Dirichlet and Neumann problems are included.