• 한국ITS학회:학술대회논문집
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• 2010.05a
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• pp.96-97
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• 2010

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.636-644
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• 1999

Experimental and simulation results are presented on the Aperture-Coupled microstrip patch antennal with U-shaped slot. Experiment and simulation results include impedance bandwidth, copolar and crosspolar-pattern characteristics and gain measurements. Simulation results show the advantages of U-slotted patch antenna comparing with the normal patch antenna. More than 35% impedance bandwidth is obtained with reasonably restricted cross-polar radiation pattern. The U-slotted radiation element fed by aperture-coupling method can be more easily extended to array structure, compared with that fed by coaxial cable.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.350-353
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• 2000

In this paper, we designed the microstrip patch antenna with L-shaped aperture, which greatly enhances its bandwidth. We optimized to get a maximum bandwidth. The microstrip patch antenna with L-shaped aperture has the widest bandwidth of the conventional aperture coupled microstrip patch antenna. This antenna also has the low-cross polarization level. The effects of changing several key design parameters of the antenna are investigated. We calculated the VSWR, input impedance, and radiation pattern.

• Journal of Chest Surgery
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• v.22 no.1
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• pp.74-82
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• 1989

Ninety-six patients with tetralogy of Fallot have undergone either primary total correction [71], staged total correction [9], or an initial shunt [16], between January, 1984, and December, 1987 Their mean age was 9.5 years, mean body weight 24kg, and mean body surface area 0.86m2. Initial palliative shunt group had smaller size, smaller pulmonary artery, and higher hemoglobin [P value < 0.05 >. Modified Blalock-Taussig shunt was performed most commonly. Patch enlargement of right ventricle in 31 cases [38%], right ventricle and pulmonary artery in 7 cases [9%], transannular patch enlargement in 28 cases [35%], and valved conduit in 2 cases [2.5%] was performed for reconstruction of right ventricular outflow tract stenosis. Longer aorta cross clamp time was noted in case of separate patch enlargement of right ventricle and pulmonary artery, and dead patient with transannular patch enlargement [P value < 0.05]. There was no operative death in shunt group, but 7 deaths in total correction group [mortality rate 8.8%].

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.652-657
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• 2008

A stress distribution of composite laminates patches is obtained by using the Kantorovich method when the substrate is under uniaxial load. The analysis is based on the stress function approach and uses the complementary virtual work principle. The three-dimensional stresses satisfy the traction free conditions at the free edges and the top surfaces of the patch. The stress of the bottom surfaces of the patch is obtained from equilibrium equation of patch and substrate. To demonstrate the efficiency and validity of the proposed analysis, numerical examples for cross-ply and quasi-isotropic laminates are included. The present method provides accurate stresses in the interior and near the free edges of composite laminate patches.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.62-67
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• 2002

It has been shown that the vibrational response of a tire can be represented by a set of decaying waves, each associated with a particular cross-sectional mode shape in the region near the contact patch. Thus, it can be concluded that tires can be effectively modeled as lossy waveguides. It has also been shown that the sound radiation from tires is mainly from the region close to the contact patch. In consequence, it may be computationally efficient to analyze tire vibration and sound radiation in the region close to the contact patch by using a hybrid finite element model in which the cross-section of a tire is approximated by 2-D finite elements while an analytical wave solution is assumed in the circumferential direction of the tire. In this article. a hybrid finite element was formulated based on a composite shell model. The dispersion relations for sample structures obtained by using the hybrid FE model were then compared with those obtained by using a full, three-dimensional FE model. It has been shown that the FE analysis made using the hybrid 2-D finite elements yields results in close agreement with the three-dimensional model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.79-80
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• 2016

In this paper, we considered a design method for a microstrip patch antenna fed through two radiating edges by two feeding microstrip lines. Two feedlines are made to have a phase difference of 180 degree with each other in order to reduce cross-polarization level radiated from the antenna. The operation principle and design procedure for the considered antenna are explained using equivalent circuits. In order to check the validity of this study, the results for reflection coefficients of the antenna obtained by the proposed equivalent circuit method and the simulation using commercial antenna design tool are compared with each other.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.12
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• pp.2468-2478
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• 1994

A hybrid finite element method is presented for a characterization of scattering an radiation properties of microstrip patch and arrays residing in a cavity recessed in a ground plane. The technique combines the finite element and boundary integral methods to formulate a system for the solution of fields at the aperture and the scattering field and radar cross sections at free space. By virture of the finite element method, the proposed technique is applicable to patch antennas and arrays residing on or embeded in a layered dielectric loss/lossless substrate and is also capable of treating various feed configuration. Several numerical results are presented demonstrating the validity, efficiency and capability of the technique.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.401-404
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• 2000

We designed and fabricated partially shorted MSA with a slot for 850 MHz on Copper-clad Laminate substrate, where the width of the radiation patch is identical with that of the ground plane and one side of the radiation patch is partially shorted to the ground plane. The radiation patterns of ZX, XY and ZY planes were measured. As a result, a better co and cross polarization lot ZX plane was obtained, compared to the partially shorted MSA without a slot.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.314.1-314
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• 2002

It has been shown that the vibrational response of a tire can be represented by a set of decaying waves, each associated with a particular cross-sectional shapes, in the region near the contact patch. Thus, it can be concluded that tires can be effectively modeled as lossy waveguides. It has also been shown that the sound radiation from tires is mainly from the region close to contact patch. (omitted)