• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.37-42
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• 1986

This paper deals with comparison of simultaneous geodetic networks between with geographical coordinates and with plane coordinates. The adjustment computation is performed by variation of coordinates. Provisional values for observation equations are computed by extended Guass mid-latitude formula using, official coordinates ($\varphi,\lambda$) in geographical network abjustment, measurements are reduced to plane by origin scale factor (＝1.0000) Bessel ellipsoid and unit weight are adopted, and geographical coordinates are projected by Guass conformal double projection. The processing results of a test-network by distances yield the average root mean square error of position 6ㆍ2cm for adjustment with $\varphi,\lambda$ and 5.8cm for adjustment with X, Y. RMSE of discrepancy between two methods is 1.7cm. This result conform to required accracy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.320-323
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• 2001

A computer simulation was performed to distinguish quantitatively a color reaction in a urine analysis systems by using the spectral power distribution of LEDs, the spectral reflectance of a urine strip, and the spectral sensitivity of photodiode. The CIE tristimulus values and CIE chromaticity coordinates ware modified to be conformable with real color reactions in a urine strips. Results on color simulation showed a of real color in comparison with those obtained by Colorimeter CM2C(Color Savvy).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.328-331
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• 2001

Color simulation on a portable colorimeter was performed to distinguish quantitatively a chromaticity coordinates on a color guide of a urine strips by using the spectral power distribution of chip LED, the spectral reflectance of printed objects, and the spectral sensitivity of photodiode. The CIE tristimulus values and chromaticity coordinates realized by a colorimeter were modified to be conformable with real color reactions. Experimental results showed a real color in comparison with those obtained by Colorimeter CM2C(Color Savvy).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.163-170
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• 1991

The 3 dimensional point positioning from SPOT imagery is performed by bundle adjustment methods of analytical and digital photogrammetry, and need the precise determination of image coordinates and accurate coordinates of ground control points. In this study, the authors analysed the digitized planimetric accuarcy and height accuracy of topographic maps in comparison with accurate coordinates by coordinates resulted by bundle adjustment in each cases between different acquisition method of ground control point coordinates and formats of SPOT imagery.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.7 s.112
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• pp.712-719
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• 2006

This paper is concerned with the comparison of substructure synthesis methods based on global and local coordinates. The substructure synthesis methods based on the global coordinates were first proposed for the dynamic analysis of complex structure and the substructure synthesis method based on the local coordinates was proposed to solve the dynamic problem of tree-like structure. However, the conceptual difference between two methods in solving the dynamic problem has never been explained. In this paper, a structure consisting of two beams is considered to show the conceptual difference of two methods. The dynamic formulation shows the characteristics and differences of two methods explicitly. The procedure for choosing proper substructure modes in each method is also explained in detail. In addition, the advantage of the substructure synthesis method based on the local coordinate system is discussed based on the numerical example. Numerical examples show how two methods are applied to the addressed problem.

• Progress in Medical Physics
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• v.10 no.1
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• pp.47-54
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• 1999

Purpose: To verify the BRW coordinates of target located within the limit of XKnife hardware, and to verify the successful transfer of image data, rod detection, anatomical structure when CT images are transferred into a XKnife computer. Materials and Methods: Target coordinates of 13 patients were calculated by SCS1 computer through the rod image on the console screen and film. BRW coordinates of target and landmark calculated by SCS1 computer were compared to those acquired by XKnife localizer. Results : Vertical components of BRW coordinates of target for 13 patients are larger than -50 mm, and then the vertical components of BRW coordinates of target are localized within the limit of XKnife hardware. Average differences between XKnife and SCS1 for BRW coordinates of target and landmark were within 1 mm for AP and LAT components, 0.5 mm for VERT component. Conclusion : It was verified that the SCS1 computer is adequate tool to calculate BRW coordinates of target quickly. And by the comparison between SCS1 computer and XKnife localizer, it was verified that the image transfer into the XKnife computer was performed successfully.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.5
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• pp.1613-1623
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• 1996

In this paper, two discretization methods, hybrid and QUICK, are tested for the Navier-Stokes equations written in general nonorthogonal body fitted coordinates. Comparison is made by calculating two laminar flows at low Reynolds numbers of 10 - 100. One is a two-dimensional channel of gradually expanding cross section and the other is an axisymmetric flow through a circular tube having a circular constriction. Results show that the QUICK scheme results in a numerical solution more accurate than that of hybrid. The QUICK scheme also shows faster convergence for both test cases. As the number of grid points increases, all numerical solutions converge with more oscillation. The number of grid points in the y-direction(cross stream direction) is also shown to play a significant role in the approximation of convection term within separated flow zone.

• Journal of Biomedical Engineering Research
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• v.17 no.4
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• pp.469-478
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• 1996

In the conventional digital ultrasound scanner, the reflected signal is sampled either in polar coordinates of R-$\theta$ method, or in Cartesian coordinates of uniform ladder algorithm (ULA). The R-$\theta$ scan method necessitates a coordinate transform process which makes hardware complex in comparison with ULA scan mrthoA In spite of this complexity, R-$\theta$ method has a good resolution in ultrasonographic (US) image, since scan direction of the US imaging is a radial direction. In this paper, a new digital scan converter is proposed, which is named the radius uniform ladder algorithm (RULA). The RULA has the rome scan direction as the US scanning in the radial direction and as the display space in the $\theta$ direction. In tllis new approach, sampled points we uniformly distributed in each horizontal line i.n well as in each radial ray so that the data are displayed in the Cartesian coordinates by the 1-D interpolation process. The propped algorithm has an uniform resolution in the periphery and the center field in comparison with equi-angle ULA and equi-interval ULA. To extend the scan angle, concentric square raster sampling (CSRS) is adopted with reduction of discontinuities on the junctions between horizontal scan and vertical scan. The discontinuities are reduced by using the hmction filtering along the $\theta$ direction.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.4
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• pp.415-423
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• 2001

This paper deals with the data processing method relative to reference frames through the calculation of absolute coordinates of permanent GPS site which was established at Sungkyunkwan University. In this paper. we computed the ITRF97 coordinates with high precision (0.0001 ppm) from GPS data analysis. Also, we derived the accurate coordinates referred to WGS84 and Korean Geodetic Datum (KGD) using transformation parameters provided. ITRF97 coordinates were computed by using the GIPSY-OASIS II (GOA II) software and the algorithms for determining the position developed Jet Propulsion Laboratory (JPL). The coordinates referred to WGS84 and KGD were derived from the transformation parameters provided by International Earth Rotation Service (IERS) and National Geography Institute (NGI). The parameters determined by NGI were calculated from the 2000 project of the establishment of geocentric coordinate system. We tested its availability through the comparison of the coordinates obtained from local GPS data analysis.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.4
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• pp.7-12
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• 2004

Inspection and analysis are essential process to determine whether a completed product is in given specification or not. Analysis of products with very complicated shape is difficult to carry out direct comparison between inspected coordinate and designed coordinates. So process called as matching or registrations is needed to solve this problem. By defining error between two coordinates and minimizing the error, registration is done. Registration consists of translation, rotation and scale transformations. Error must be defined to express feature of inspected product. In this paper, registration algorithm is developed to determine pose of sub-frame at assembly with body of automobile by defining error between two coordinates considering geometric feature of sub-frame.