• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.105-112
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• 2000

In-Ceram system is one of contemporary esthetic all ceramic restorations and has relatively high flexural strength. The purpose of this study was to evaluate the marginal fit of In-Ceram crown according to shoulder width and measuring position. In this study, twenty seven In-Ceram crowns devided into three groups, each prepared with shoulder width of 0.6mm, 0.9mm and 1.2mm. All specimens were cemented with glass ionomer cement. After cementation, specimens were measured marginal gap between the margin of the In-Ceram crown and the finishing line of resin master die by using a refrective microscope. Marginal gaps were recorded at the labial, lingual, mesial and distal measuring points on the resin master die. The results of this study were as follows: 1. Mean marginal fits of each group were $81.28{\mu}m$ in 0.6mm shoulder width, $70.78{\mu}m$ in 0.9mm shoulder width and $67.75{\mu}m$ in 1.2mm shoulder width. 2. There was significant difference between group 0.6mm and 0.9mm, 1.2mm.(p<0.05). 3. In comparison of marginal fit according to the measuring points, there was no significant difference.

• Journal of Fashion Business
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• v.16 no.5
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• pp.57-73
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• 2012

The main objective of this research was to understand the characteristics of pleats design through the analysis of modern female fashion as they appear in the 'Collections' from '09 A/W to '12 S/S. Data collection of 1027 was done through the review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of three cities; Milan, New York, Paris. Along with the qualitative interpretation of pleats design, statistical analysis of frequency and ${\chi}^2$-test were completed for data analysis. The main findings were as follows; 1. The five types of pleats design were founded in the order of accordion, knife, box, inverted, and sunburst pleats. The frequency and ratio of pleats design occurency showed significant difference between collections. 2. There were significant difference between the types of pleats and their line characteristics of thickness, continuity, length, direction. = Thin fabrics with delicate fine folds were mainly appeared in accordion and sunburst pleats. On the other hand, midium thickness fabrics were used for knife, box & inverted pleats, however, the different images were projected according to the width and the number of folds, characteristics of fabrics and textures. = In all the type of pleats but sunburst, continuity line was appeared the most. The discontinuous lines were appeared the most in the layered types and, sometimes, at some construction lines to add some decorative details or design variations. = The long line were the most frequently appeared in long one-pieces or long skirts of knife, accordion, sunburst pleats. While, the shorter lines showed the most frequently in box and inverted pleats, which mainly used for skirts or the lower part of one-piece. = For the line directions, the vertical lines were the most frequently appeared, and followed by mixed and diagonal line. In mixed or diagonal lines, same type of pleat was repeated in one design. For diagonal lines, one direction was mainly used, however, the symmetrical arrangements or repeated diagonal pleats in various directions also used. In mixed lines, the type of one or two diagonal and one vertical line was the most frequently appeared.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.3
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• pp.36-45
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• 2010

To analyze the relationship between climatic factors (monthly mean temperature and total precipitation) and tree-ring growths of Quercus mongolica Fischer (Mongolian oak) with different topographic sites in Mt. Worak, more than 10 trees were selected from each of seven stands. Two cores from each tree were measured for ring width. After crossdating, each ring-width series was double standardized by fitting first a negative exponential or straight regression line and secondly a 60-year cubic spline. Seven stands were categorized in two groups using cluster analysis for tree-ring index patterns. Cluster I (four stands) was located in higher elevation (550-812 m) with aspects of east, west and northwest, and cluster II (three stands) was located in rather lower election (330-628 m) with aspects of north and northwest. The aspects of two clusters were not significantly different. Response-function analysis showed a significant positive response to March precipitation for both clusters. It indicates that moisture supply during early spring season is important to radial growth because the cambial growths of ring-porous species, such as Mongolian oak, start before leaf growth. Cluster II showed a positive response to the precipitation of middle and late growing season, too.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.4
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• pp.397-402
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• 2003

This paper concerns a pulse-width-modulation (PWM) controller design technique using digital redesign. Digital redesign is to convert a well-designed analog controller into an equivalent pulse-amplitude-modulation (PAM) controller maintaining the original analog control system in the sense of state-matching. In similar line of conversion concept, the redesigned PAM controller is converted into a PWM controller using the equivalent area principle. To convincingly visualize the proposed technique, an computer simulation example-attitude control of artificial satellite system is included.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.89.2-89.2
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• 2013

Solar energetic transients, e.g., flares, CMEs, etc., release large amount of energy which is expected to excite acoustic waves (p-modes) by exerting mechanical impulse of the thermal expansion of the flare on the photosphere. We study the p-mode properties of flaring and dormant active regions (ARs) to find association between flare and p-mode parameters. We compute the magnetic and flare activity indices of ARs using the line-of-sight magnetograms and GOES X-ray fluxes, respectively. The p-mode parameters are computed from the ring-diagram analysis. We correct p-mode parameters for magnetic field, filling factors and foreshortening by multiple linear-regression analysis. Our analysis of several flaring and dormant ARs observed during the Carrington rotations 1980-2109, showed strong association of mode parameters with magnetic and flare activities. We find that the mode parameters are contaminated by the geometrical effect. Mode amplitude decreases with angular distance from the solar disc centre. The mode width increases with magnetic activity while amplitude showed opposite relation due to mode absorption by the sunspot. After correcting modes due to all geometrical effects, magnetic activity and filling factor, we find that the modes amplitude, and mode energy increases with flare energy while width shows opposite relation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.5
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• pp.479-488
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• 2003

Dual-band microstrip antenna is designed for industrial-scientific-medical(ISM) band of 2.4 GHz and 5.8 GHz using finite-difference time-domain method(FDTD). Cross patch 130 by aperture in the ground plane of microstrip line is proposed as radiation element of antenna which is 2 rectangular patch is overlapped. To design antenna, change of input impedance is examined by length change of aperture and stub. And center frequency and - 10 dB bandwidth are investigated by change of length and width in radiation element. Measured result about reflection loss confirm that agree well with simulation results of FDTD and IE3D. And 3 dB beam width, front to back ratio and maximum gain is presented by measuring radiation pattern of antenna in frequency 2.43 GHz and 5.79 GHz.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.590-595
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• 2004

The shape and size variations of the nanopatterns produced on a positive photoresist using a near-field scanning optical microscope(NSOM) are investigated with respect to the process variables. A cantilever type nanoprobe having a 100nm aperture at the apex of the pyramidal tip is used with the NSOM and a He-Cd laser at a wavelength of 442nm as the illumination source. Patterning characteristics are examined for different laser beam power at the entrance side of the aperture( $P_{in}$ ), scan speed of the piezo stage(V), repeated scanning over the same pattern, and operation modes of the NSOM(DC and AC modes). The pattern size remained almost the same for equal linear energy density. Pattern size decreased for lower laser beam power and greater scan speed, leading to a minimum pattern width of around 50nm at $P_{in}$ =1.2$\mu$W and V=12$\mu$m/. Direct writing of an arbitrary pattern with a line width of about 150nm was demonstrated to verify the feasibility of this technique for nanomask fabrication. Application on high-density data storage using azopolymer is discussed at the end.

• The Journal of the Acoustical Society of Korea
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• v.13 no.6
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• pp.45-49
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• 1994

In this paper, photoacoustic image processing system was constructed by using 2W CW $CO_{2}$ laser of $10.6{\mu}m$ wavelength and PZT 5A acoustic transducer. Stainless steel of 5mm thickness was used as a sample in experiment. Three line cracks of $50{\mu}m$ in each width and depth were made by using plasma on the surface of the sample. Also, each gap among their lines was $200{\mu}m$ and $300{\mu}m$ in width. In the scan range of $2.2mm\times2mm$ including surface defects, a good image of $50{\mu}m$ resolution had been shown when modulation frequency of CW laser was 100Hz.

• Journal of electromagnetic engineering and science
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• v.2 no.1
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• pp.50-55
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• 2002

In this paper, Ive propose a bow-tie-shaped meander slot antenna find by a microstrip line to achieve compact size as well as wideband characteristic. While conventional bow-tie slot antennas exhibit wide band characteristic, they have relatively large size. On the other hand, the meander slot antennas are very small, but they reveal quite narrow bandwidth (typically less than 1 %). To realize miniaturized antennas balling large bandwidth, combination of the bow-tie slot and the meander slot geometries is proposed in this paper. Theoretical results show that the proposed antenna with uniform slot width is 65.5 % smaller than that of the conventional bow-tie antenna in size, while the bandwidth is 3 times larger than that of the meander slot antenna. Moreover, the non-uniform slot width antenna shows 60 % smaller in size and about 3.5 times wider in bandwidth than the previous antennas. Measured antenna performance reveals excellent agreement with the predicted values.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.726-731
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• 2004

This paper proposes a pulse-width-modulation (PWM) controller design technique using intelligent digital redesign. Intelligent digital redesign is to convert a well-designed analog fuzzy-model-based controller into an equivalent pulse-amplitude-modulation (PAM) digital controller maintaining the original analog control system in the sense of state-matching. In similar line of conversion concept, the redesigned PAM intelligent digital controller is converted into a PWM controller using the equivalent area principle. To convincingly visualize the proposed technique, an computer simulation example-attitude control of nonlinear artificial satellite system is included.