• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2000-2006
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• 2000

The enhancement of service life of damaged or cracked structures is currently major issue to the researchers and engineers. In order to improve the life of cracked aging aircraft structures, the repair technique which uses adhesively bonded boron/epoxy composite patches is being widely considered as a cost-effective and reliable method. This paper is to study the performance of the bonded composite patch repair of a plate containing an inclined central through-crack. A 3-dimensional finite element method having three layers to the cracked plate, composite patch and adhesive layer, is used to compute the stress intensity factor. In this paper, the reduction of stress intensity factors near the crack-tip are determined to evaluate the effects of various non-dimensional design parameter including composite patch thickness, and material properties of the composite patch and thickness of the adhesive layer, materials of patch etc., and the crack length, Finally, The problem of how to optimize the patch geometric configurations has been discussed.

• ETRI Journal
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• v.33 no.2
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• pp.163-168
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• 2011

A Fabry-Perot cavity (FPC) antenna producing both high-gain and circularly-polarized (CP) behavior is proposed. To increase antenna gain and obtain CP characteristics, a superstrate composed of square patches with a pair of truncated corners is placed above the linearly polarized patch antenna with an approximately half-wavelength distance from the ground plane at the operating frequency. The proposed antenna has the advantages of high gain, a simple design, and an excellent boresight axial ratio over the operating frequency bandwidth. Moreover, used in an FPC antenna, the proposed superstrate converts a linear polarization produced by a patch antenna into a circular polarization. In addition, the cavity antenna produces left-hand circular-polarization and right-hand circular-polarization when a patch antenna inside the cavity generates x-direction and y-direction polarization, respectively. The measured and simulated results verify the performance of the antenna.

• The Korean Journal of Ecology
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• v.14 no.3
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• pp.327-343
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• 1991

Clonal growth and rhizome architecture of calmagrostis epigeios, were studied in a 15-year old coastal reclamed land. As c. epigeios patch grew from center to margin radially over time, concentric annuli were added. the radial increases of the mature patch were 80~130cm/yr. the patch ages of c. epigeios estimated by relationships between the diameter and is radial increament, were 1~6year old. There were the marked variations of density, phytomass, shoot height and inflorecence frequency with increasing age of rhizome system within the patch. the maximum performance occurred at 2-year-old concentric annuli of the patch. The growth phasic continuum with aging was divided into 5 grwth phases ; pioneer, building, matyre, senile and degenerate. The rhizome aging had a more significant effect on the inflorescence frequency than on the other attributes. new rhizomes tended to diverge from the direction of the parent ramet by sympodial growth. in a 1-year-old patch, average length of rhizome segment was 7cm, average number of internode was 6, and the tillering frequency was 27%. The tillering in the early stage resultd in the increase of shoot density and the producation of multibranching rhizome. as the result of that, circular patchwas formed in a year. The branching structure based on such facts was represented graphically in branching degree of 60 and 100. therefore, c. epigeios with clonal growth may establish and grow vigorously earlier than other glycophytes in high salt conditions such as the coastal reclaimed land.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.525-529
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• 2009

In this paper, microstrip patch antenna with diagonal slotted type using RFID is designed. This microstrip patch antenna is designed by considering the properties of critical parameter like the size, the truncating dimension, position of feed power and the height of airspace. the designed microstrip patch antenna has the lowest return loss in 915MHz, and in case of the voltage standing wave ratio(VSWR) is less than 1.2 under return loss -16dB, it has bandwidth of about 26MHz. Also, the microstrip patch antenna has the gain of 6dBi on the center frequency of 915MHz band and 2.8dB in the rate of reduction.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.117-121
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• 2006

Ability of pectic polysaccharides isolated from Eleutherococcus senticosus EN-3 to inhibit tumor metastasis and induce antigen-specific immune response after oral administration in mice was assessed. Consecutive oral administration of EN-3 before tumor inoculation dramatically inhibited tumor metastasis produced by colon26-M3.1 and B16-BL6 cells. When Peyer's patch cells isolated from mouse intestine were co-cultured with EN-3, proliferation of Peyer's patch cells was induced. Mice co-administered with EN-3 and ovalbumin (OVA) showed significantly higher production of OVA-specific IgA in intestinal washing as well as IgG in serum than those administered with OVA alone. Payer's patch cells of mice immunized with OVA plus EN-3 showed much higher proliferating activity than those of mice immunized with OVA alone. Proliferating activity increased dose-dependently, indicating EN-3 specifically enhanced mucosal immune response to OVA. These results suggested EN-3 could significantly stimulate Peyer's patch cells either non-specifically or antigen-specifically, possibly playing important role in enhancement of mucosal and systemic immune systems.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.187-190
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• 2007

This study is for analyzing best band in image matching using correlation coefficient of left and right images of stereo image pair, lot red, green, blue band images separated from color aerial photo and gray image converted from the same color aerial photo image. The image matching is applied to construct Digital Elevation Model(DEM) or terrain data. The correlation coefficients and variation by change of pixel patch size are computed from pixel patches of which sizes are $11{\times}11{\sim}101{\times}101$. Consequently, the correlation coefficient in red band image is highest. The lowest is in blue band. Therefore, to construct terrain data using image matching, the red band image is preferable. As the size of pixel patch is growing, the correlation coefficient is increasing. But increasing rate declines from $51{\times}51$ image patch size and above. It is proved that the smaller pixel patch size than $51{\times}51$ is applied to construct terrain data using image matching.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.197-200
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• 2004

In this paper, a novel triple-band planar inverted F antenna(PIFA) is proposed. The goal of this paper is to design a small antenna which is operated in triple band. Using T-shape slit and stacked U-shape parasitic patch, good impedance matching is achieved in three band. T-shape slit is inserted on the main patch in order to effectively control the excited patch surface current distributions. The proposed antenna occupies a small volume of $26{\times}9.5{\times}6mm^3$, and the obtained impedance bandwidths cover the required operating bandwidths of the GPS(1565-1585MHz), IMT-2000(1885-2200MHz) and Bluetooth (2400-2484MHz) bands.

• 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 Yeungnam Medical Science
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• v.29 no.1
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• pp.58-60
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• 2012

Central anticholinergic syndrome occurs when an anticholinergic substance works in vivo or as a result of the insufficient release of acetylcholine. Its symptoms include confusion, agitation, behavioral change, hallucination, blurred vision, and dysarthria. Occasionally, these symptoms occur with the use of a scopolamine patch. A 54-year-old female complained of behavioral change and confused mentality. She attached a scopolamine patch at the postauricular area in the morning of the day before her hospital visit. Neurological examination revealed bilateral symmetric mydriasis without light reflex. The brain MRI was normal, and electroencephalography showed nonspecific abnormalities. The patient recovered completely after the removal of the scopolamine patch.

• ETRI Journal
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• v.28 no.3
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• pp.379-382
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• 2006

A novel reconfigurable microstrip patch antenna with frequency and polarization diversities is proposed. A U-slot is incorporated into a square patch, and a PIN diode is utilized to switch the slot on and off, which realizes the frequency diversity characteristic. The polarization diversities among linear polarization (LP), right-hand circular polarization (RHCP), and left-hand circular polarization (LHCP) are also obtained by switching three PIN diodes on the slot and the truncating corners of a square patch on and off. The antenna design and experimental results are presented.