• Journal of Advanced Navigation Technology
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• v.10 no.4
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• pp.385-393
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• 2006

In this paper, we proposed a location estimation algorithm considering an extension of searching area in 2.45GHz band RTLS and analyzed its performance in terms of an average estimation error distance. The extendable searching area was assumed to be square of $300m{\times}300m$ and 2 dimensions. The arrangement shape of available readers was considered circle, rectangle, and shrinkage rectangle for extendable searching area. Also, we assumed that propagation path was LOS (Line-Of-Sight) environment, and analyzed the estimation error performance as a function of the number of received sub-blink considering an arrangement shape of available readers in searching area. From the results, compared with rectangle shape, circle shape showed the higher estimation accuracy. Also, we confirmed that the proposed location estimation algorithm provided high estimation accuracy in the shrinkage rectangle shape that was suitable for extension of searching area.

• The Pure and Applied Mathematics
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• v.19 no.4
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• pp.337-347
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• 2012

The taxicab distance and Chinese-checker distance in the plane are practical distance notions with a wide range of applications compared to the Euclidean distance. The ${\alpha}$-distance was introduced as a generalization of these two distance functions. In this paper, we study alpha circle, trigonometry, and the area of a triangle in the plane with ${\alpha}$-distance.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1190-1199
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• 2016

This study proposes a classification and compensation algorithm of two non-ideal output signals of a resolver to reduce position errors. Practically, a resolver generates position errors because of amplitude imbalance and quadrature imperfection between the two output signals of the resolver. In this study, a digital signal processor system based on a resolver-to-digital converter is used to reconstruct the two output signals of the resolver. The two output signals, "sin" and "cos," can be represented by a unit circle on the xy-plot. The classification and compensation of the errors can be obtained by using the radius and area of the circle made by the resolver signals. The method computes the integration of the areas made by the two resolver output signals to classify and compensate the error. This system cannot be applied during transient response given that the area integration during the transient state causes an error in the proposed method. The proposed method does not need any additional hardware. The experimental results verify the effectiveness of the proposed algorithm.

• The Research Journal of the Costume Culture
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• v.7 no.5
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• pp.80-92
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• 1999

The objectives of this study were to investigate the relation between personality(activity, emotional stability, and dominance) and clothing design preferences, and to examine the differences of clothing design preferences according to demographic variables of men. Subjects for the study were 255 male white-collar workers ranging in ages from twenties to fifties, in Seoul and Kwangju City, Korea. The men with higher activity of personality preferred the double jacket with 4 buttons, the combination of light color jacket and dark trousers, glen check pattern jacket, herringbone pattern jacket, light beige color dress shirts. The higher the emotional stability, the higher the preferences on diverse patterns such as fine stripe, plaid, hound\`s-tooth check, and small check pattern. The men with higher dominance preferred dark blue color suit, glen check pattern suit, and necktie of red circle, and disliked the necktie of gray circle. The men in their 20\`s and 30\`s liked the single jacket with 3 buttons, the suit of fine stripe and the necktie of gray circle more among three income groups. The higher the men\`s age and income were, the more they liked the conservative style such as a single jacket with 2 buttons. The men who reside in Seoul liked the suit of gray circle, the jacket and trousers of same color, the patternless jacket, and the patternless suit more than the men in Kwangju. Therefore, the men in methropolitan area preferred conservative clothing image. Fine stripe pattern and patternless materials were preferred when men wore jacket and trousers of same color, while glen check pattern was preferred as the pattern of jacket when jacket and trousers of different color. Male white-collar worker liked single jacket more than double jacket, and preferred the dark blue color suit and necktie, patternless suit, fine stripe suit, and the pale blue dress shirts generally. The present findings provide that the personality of male has influence on the clothing design preferences, and it is possible to infer men\`s personality by their attire.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.313-318
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• 2019

The purpose of this study is to investigate whether there is a difference in the incidence of the black circle border of iris(skin disease) according to the iris constitution. Iris was taken for 100 adults living in Seoul. Iris was photographed using the iris camera DV-2H, a blue focus development product. Statistical significance was tested by correlation analysis, and the occurrence of black circle border of iris was low negative correlation(p<0.01). As mentioned above, we know that the occurrence of black circle border of iris differs according to the iris constitution, and by using it actively, it will help health promotion about skin. There is a need to study the changes of iris in the cause of skin disease by using a blood test to analyze the cause of the skin disease in the future.

• Korean Journal of Optics and Photonics
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• v.12 no.3
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• pp.165-171
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• 2001

We discuss the influence of annular binary filters on the axial PSF of imaging systems which are apodized by a radiallysymmetric filter and have spherical aberration and coma. In this paper we consider a whole family of annular binary fIlters in two cases. First, the binary filters are composed of two transparent annuli of the same area. Second, the binary filters are composed of a central clear circle and a concentric annular aperture with area bigger than that of the inner circle. In order to investigate the influence of the proposed filters on the axial PSF, we may use the axial resolution gains, which evaluate in terms of the FWHM of the intensity in the focal region of an apodized imaging system in comparison with that corresponding to a nonapodized one. We evaluate the PSF for the conventional and confocal systems having an aberration. ation.

• Steel and Composite Structures
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• v.29 no.6
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• pp.771-783
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• 2018

In this paper, topology optimization (TO) is applied to find a new configuration for the perforated steel plate shear wall (PSPSW) based on the maximization of reaction forces as the objective function. An infill steel plate is introduced based on an experimental model for TO. The TO is conducted using the sensitivity analysis, the method of moving asymptotes and SIMP method. TO is done using a nonlinear analysis (geometry and material) considering the buckling. The final area of the optimized plate is equal to 50% of the infill plate. Three plate thicknesses and three length-to-height ratios are defined and their effects are investigated in the TO. It indicates the plate thickness has no significant impact on the optimization results. The nonlinear behavior of optimized plates under cyclic loading is studied and the strength, energy and fracture tendency of them are investigated. Also, four steel plates including infill plate, a plate with a central circle and two types of the multi-circle plate are introduced with equal plate volume for comparing with the results of the optimized plate.

• Journal of the Semiconductor & Display Technology
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• v.9 no.1
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• pp.11-16
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• 2010

Wafer Pre-Alignment is to find the center and the orientation of a wafer and to move the wafer to the desired position and orientation. In this paper, an area camera based pre-aligning method is presented that captures 8 wafer images regularly during 360 degrees rotation. From the images, wafer edge positions are extracted and used to estimate the wafer's center and orientation using least squares circle fitting. These data are utilized for the proper alignment of the wafer. For accurate alignments, camera calibration methods using high order polynomials are used for converting pixel coordinates into real-world coordinates. A complete pre-alignment system was constructed using mechanical and optical components and tested. Experimental results show that alignment of wafer center and orientation can be done with the standard deviation of 0.002 mm and 0.028 degree, respectively.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.2
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• pp.121-129
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• 1993

Plane strain punch stretching test (PSST) was developed to evaluate stamping formability of sheet materials. In this test, the rectangular specimen of sheet material is uniformly stretched up to fracture by raising a specially designed punch to certainly assure plane strain stretching deformation along the longitudinal direction of the specimen. The stamping formability was evaluated by limit punch height(LPH) in plane strain punch stretching test compared to limit dome height(LDH) in hemispherical punch stretching test. LPH-value in PSST well ranks the stamping formability of various material and correlates with press performance. Moreover by using ultrasonic thickness gauge the plane strain intercept-limit plane strain(FLCo)-in forming limit curve can be accurately determined from thickness measurement around the fracture area. The FLCo derived from thickness measurement well correlates with the results from circle grid analysis for the deformed circle grid marked on the surface of the specimen.

• Journal of the Korean Home Economics Association
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• v.36 no.3
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• pp.191-206
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• 1998

The purpose of this study was to explore social support in childhood and early adolescence. The research was based on the social convoy model(Kahn and Antonucci, 1980). The data were collected from questionnaires completed by 656 elementary school children(2nd and 5th grade) and the middle school children(2nd grade) in rural and urban area. The statistical methods adopted for data analyses were frequencies, mean, standard deviation, T-test, One-way ANOVA, Scheffe-test, Two-way ANOVA, and correlation coefficient. Children received more support from parents and friends in convoy function of social support. Convoy size of social support increased with age. Rural children had larger convoy size in the inner circle, and smaller convoy size in the middle circle than urban children did.