• The Korean Journal of Applied Statistics
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• v.24 no.2
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• pp.373-381
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• 2011

This paper discusses how to get the sums of squares due to treatment factors when Type I Analysis is used by projections for the analysis of data under the assumption of a two-way ANOVA model. The suggested method does not need to calculate the residual sums of squares for the calculation of sums of squares. There-fore, the calculation is easier and faster than classical ANOVA methods. It also discusses how eigenvectors and eigenvalues of the projection matrices can be used to get the calculation of sums of squares. An example is given to illustrate the calculation procedure by projections for unbalanced data.

• Journal of the Chungcheong Mathematical Society
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• v.34 no.2
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• pp.181-188
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• 2021

Let X be a nondegenerate reduced closed subscheme in ℙⁿ. Assume that π_q : X → Y = π_q(X) ⊂ ℙ^n-1 is a generic projection from the center q ∈ Sec(X) \ X where Sec(X) = ℙⁿ. Let Z be the singular locus of the projection π_q(X) ⊂ ℙ^n-1. Suppose that I_X has the almost minimal presentation, which is of the form R(-3)^β_2,1 ⊕ R(-4) → R(-2)^β_1,1 → I_X → 0. In this paper, we prove the followings: (a) Z is either a linear space or a quadric hypersurface in a linear subspace; (b) $H^1({\mathcal{I}_X(k)})=H^1({\mathcal{I}_Y(k)})$ for all k ∈ ℤ; (c) reg(Y) ≤ max{reg(X), 4}; (d) Y is cut out by at most quartic hypersurfaces.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.337-343
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• 1998

In Korea, map coordinates has been confused in use since the map projection system has been complicated by using two different methods i.e., Gauss conformal double projection and Gauss-Kruger projection which are com-plicated in using through history. So, we have to understand the two projections' characteristics and differences. In this study, we would find out a fact that the maximum difference occurred in longitude and latitude is about 15cm at the Korean peninsular. This shift is accepted as proper in GIS and cartographic application but should be considered carefully in converting of the geodetic control point coordinates.

• Journal of the Korean Data and Information Science Society
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• v.25 no.6
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• pp.1549-1555
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• 2014

Consider a p-variate normal distribution ($p-q{\geq}3$, q = rank($P_V$) with a projection matrix $P_V$). Using a simple property of noncentral chi square distribution, the generalized Bayes estimators dominating the James-Stein estimator shrinking towards projection vectors under quadratic loss are given based on the methods of Brown, Brewster and Zidek for estimating a normal variance. This result can be extended the cases where covariance matrix is completely unknown or ${\sum}={\sigma}^2I$ for an unknown scalar ${\sigma}^2$.

• Archives of Plastic Surgery
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• v.43 no.5
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• pp.424-429
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• 2016

Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A $1{\times}2-cm$ acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was $73.0%{\pm}9.67%$ for the LD flap group using an O-strut, $72.0%{\pm}11.53%$ for the TRAM flap group using an I-strut, and $69.0%{\pm}10.82%$ for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction.

• Journal of Korean Society for Geospatial Information Science
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• v.6 no.2 s.12
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• pp.119-132
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• 1998

Much information on the terrain and the space has been depicted to maps of various form according to the map scale and the application. In Korea the base map system was made by only one projection method(Transvers Mercator projection). This is the reason to study this paper, because I think singular map projection method can't satisfy the various map scales and application. In this paper Meridian Are Length, Parallel Are Length of ellipsoid and the area of ellipsoidal surface-the length, the width and area of the map scale 1/5,000, 1/25,000, 1/5,000, 1/1,000, will be calculated and transformed to the plane length and area by Transvers Mercartor projection and Polyhedrical projection. The projection distortion which came into existence on this occasion was compared and analyzed by this Paper. And Properties on TM and Polyhedrical projection were understood. Lastly this paper intended to present suitable map projections according to the map scales and the purpose of use.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.2
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• pp.121-134
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• 2013

The transverse cylindrical projection has been used in Korea since 1910s when the nationwide geodetic network was firstly established. However, the projection has a number of different types of functions according to a way of its mathematical derivation as well as a section of its coefficients and terms, for instance Gauss- Schreiber(GS) and Gauss-Kruger(GK) types. Although the transverse cylindrical projection itself is assigned to a system, projected coordinates would be diverse with respect to the function used in the actual calculation. In order to investigate impact of functions used in the computation, five different equations (i.e., 2 GS and 3 GK) were implemented in this study by using MATLAB. A series of numerical simulation tests has been carried out to compare and characterize them in terms of projection accuracy, difference of projected coordinates and distortion. Furthermore, a comparison between GS and GK function was made under the Korean gridding system, consisting of four zones. Results from the numerical computations were qualitatively analyzed and summarized in this paper.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.63.4-63
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• 2001

An x-ray vision can be a unique method to monitor and analyze the motion of mechanical parts in real time which are invisible from outside. Our problem is to identify the pose, i.e. the position and orientation of an object from x-ray projection images. It is assumed here that the x-ray imaging conditions that include the relative coordinates of the x-ray source and the image plane are predetermined and the object geometry is known. In this situation, an x-ray image of an object at a given pose can be estimated computationally by using a priori known x-ray projection image model. It is based on the assumption that a pose of an object can be determined uniquely to a given x-ray projection image. Thus, once we have the numerical model of x-ray imaging process, x-ray image of the known object at any pose could be estimated ...

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.331-332
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• 2009

We present an analysis on the quality factors of the Fourier hologram generated from multiple orthographic view images of three-dimensional object. In the analysis, we analyze both the maximum size of the reconstructed object and its spatial resolution. For the maximum size of the reconstruction, we found that the main factor is the orthographic projection angle interval. Too large projection angle interval causes overlapping in the reconstruction space domain. For the spatial resolution, there are three factors, i.e. the capturing lens array pitch which determines the spatial sampling rate of the original three-dimensional objects, the maximum orthographic projection angle, and the spatial frequency bandwidth of the object. The dominant factor is determined by the relationship between those three factors.

• Journal of the Korean Data and Information Science Society
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• v.25 no.2
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• pp.423-429
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• 2014

This paper discusses a method for getting Type I sums of squares by projections under a two-way fixed-effects model when variances of errors are not equal. The method of weighted least squares is used to estimate the parameters of the assumed model. The model is fitted to the data in a sequential manner by using the model comparison technique. The vector space generated by the model matrix can be composed of orthogonal vector subspaces spanned by submatrices consisting of column vectors related to the parameters. It is discussed how to get the Type I sums of squares by using the projections into the orthogonal vector subspaces.