• Title/Summary/Keyword: Square computing

Search Result 170, Processing Time 0.021 seconds

Nonnegative Tucker Decomposition (텐서의 비음수 Tucker 분해)

  • Kim, Yong-Deok;Choi, Seung-Jin
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.14 no.3
    • /
    • pp.296-300
    • /
    • 2008
  • Nonnegative tensor factorization(NTF) is a recent multiway(multilineal) extension of nonnegative matrix factorization(NMF), where nonnegativity constraints are imposed on the CANDECOMP/PARAFAC model. In this paper we consider the Tucker model with nonnegativity constraints and develop a new tensor factorization method, referred to as nonnegative Tucker decomposition (NTD). We derive multiplicative updating algorithms for various discrepancy measures: least square error function, I-divergence, and $\alpha$-divergence.

Improved National Datum Transformation Parameters of South Korea (국가좌표계 변환요소의 개선)

  • 이영진
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.16 no.1
    • /
    • pp.95-101
    • /
    • 1998
  • In this paper, the historical coordinates data of origin SUWON are reviewed and determination procedures are explained with the three dimensional geocentric coordinates of ITRF94 that is determined using VLBI observations. Also three translation parameters are calculated on the origin point. The national transformation parameters between the Korean geodetic system and Korean Terrestrial Reference Frame 1994(KTRF94) system, are determined using least square methods with weigted parameter constraints. The results of transformation show that one set of parameters are applicable to fixing of a position for GPS relative positioning processing and to adjusting of a network for three dimensional geocentric coordinates(KTRF94) computing.

  • PDF

Free vibrations of arbitrary quadrilateral thick plates with internal columns and uniform elastic edge supports by pb-2 Ritz method

  • Wu, L.H.
    • Structural Engineering and Mechanics
    • /
    • v.44 no.3
    • /
    • pp.267-288
    • /
    • 2012
  • Free vibration analysis of arbitrary quadrilateral thick plates with internal columns and elastic edge supports is presented by using the powerful pb-2 Ritz method and Reddy's third order shear deformation plate theory. The computing domain of arbitrary quadrilateral planform is mapped onto a standard square form by coordinate transformation. The versatile pb-2 Ritz functions defined by the product of a two-dimensional polynomial and a basic function are taken to be the admissible functions. Substituting these displacement functions into the energy functional and minimizing the total energy by differentiation, leads to a typical eigenvalue problem, which is solved by a standard eigenvalue solver. Stiffness and mass matrices are numerically integrated over the plate by using Gaussian quadrature. The accuracy and efficiency of the proposed method are demonstrated through several numerical examples by comparison and convergency studies. A lot of numerical results for reasonable natural frequency parameters of quadrilateral plates with different combinations of elastic boundary conditions and column supports at any locations are presented, which can be used as a benchmark for future studies in this area.

Automatic detection of the lung orientation in digital PA chest radiographs

  • Nahm, Kie-B.
    • Journal of the Optical Society of Korea
    • /
    • v.1 no.1
    • /
    • pp.60-64
    • /
    • 1997
  • An image processing algorithm is presented that can identify the orientation as well as the left/right side (parity) of the digitized radiographs. The orientation was found by computing the mean square deviation between the sampled gray values along the center and their best-fit linear regression relations. The parity was determined by comparing the area difference between two thresholded images of the left and the right side around the heart, which is assumed to be around the center of the image. This method was tested with 86 images with their orientations intentionally rotated. The rotation was limited to multiples of 90 degrees, as this was the way the rotation is most likely to happen in the clinical environment. We obtained positive responses for 85 out of 86 images subject to the screening.

A Study on the Evaluation of Interpolation Methods in PIV (PIV에서의 보간기법의 평가에 관한 연구)

  • 최장운;조대한;최민선;이영호
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.20 no.4
    • /
    • pp.90-100
    • /
    • 1996
  • To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

  • PDF

A Study on the Evaluation of Interpolation Methods in PIV (PIV에서의 보간기법의 평가에 관한 연구)

  • Choi, J.W;Cho, D.H;Choi, M.S;Lee, Y.H
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.20 no.4
    • /
    • pp.412-412
    • /
    • 1996
  • To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

Camera Motion Parameter Estimation Technique using 2D Homography and LM Method based on Invariant Features

  • Cha, Jeong-Hee
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.5 no.4
    • /
    • pp.297-301
    • /
    • 2005
  • In this paper, we propose a method to estimate camera motion parameter based on invariant point features. Typically, feature information of image has drawbacks, it is variable to camera viewpoint, and therefore information quantity increases after time. The LM(Levenberg-Marquardt) method using nonlinear minimum square evaluation for camera extrinsic parameter estimation also has a weak point, which has different iteration number for approaching the minimal point according to the initial values and convergence time increases if the process run into a local minimum. In order to complement these shortfalls, we, first propose constructing feature models using invariant vector of geometry. Secondly, we propose a two-stage calculation method to improve accuracy and convergence by using homography and LM method. In the experiment, we compare and analyze the proposed method with existing method to demonstrate the superiority of the proposed algorithms.

THE REPRESENTATION AND PERTURBATION OF THE W-WEIGHTED DRAZIN INVERSE

  • Xu, Zhaoliang;Wang, Guorong
    • Journal of applied mathematics & informatics
    • /
    • v.23 no.1_2
    • /
    • pp.113-126
    • /
    • 2007
  • Let A and E be $m{\times}n$ matrices and W an $n{\times}m$ matrix, and let $A_{d,w}$ denote the W-weighted Drazin inverse of A. In this paper, a new representation of the W-weighted Drazin inverse of A is given. Some new properties for the W-weighted Drazin inverse $A_{d,w}\;and\;B_{d,w}$ are investigated, where B=A+E. In addition, the Banach-type perturbation theorem for the W-weighted Drazin inverse of A and B are established, and the perturbation bounds for ${\parallel}B_{d,w}{\parallel}\;and\;{\parallel}B_{d,w}-A_{d,w}{\parallel}/{\parallel}A_{d,w}{\parallel}$ are also presented. When A and B are square matrices and W is identity matrix, some known results in the literature related to the Drazin inverse and the group inverse are directly reduced by the results in this paper as special cases.

Development of Time-dependent mean Temperature Equations for GPS Meteorology

  • Ha, Jihyun
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.3 no.4
    • /
    • pp.143-147
    • /
    • 2014
  • The mean temperature is one of the key parameters in computing Precipitable Water Vapor (PWV) from Global Positioning System (GPS) measurements and is usually derived as a function of surface temperature through the use of a mean temperature equation (MTE). In this study, two new types of MTEs were developed as functions solely of the observation time so that the mean temperature can be obtained without surface temperature measurements. To validate the new models, we created one-year time series of GPS-derived PWV using the new MTEs and compared them with the radiosonde-observed PWV. The bias and root-mean-square error were on the other of ~1 mm and ~2 mm, respectively.

A Novel Network Reduction Method based on Similarity Index between Bus Pairs (모선 간 유사지수에 근거한 새로운 계통축약 기법)

  • Chun, Yeong-Han;Lee, Dong-Su
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.55 no.4
    • /
    • pp.156-162
    • /
    • 2006
  • Transmission zones can be defined based on LMPs. Each zone consists of nodes with similar LMPs, and zonal price is determined by average nodal prices in each zone.[1] Network reduction is still important for the analysis of zonal systems under electricity market environments, even though the computing capability of computer system can deal with entire power systems. The Similarity Index is a good performance measure for the network reduction.[2] It can be applied to the network reduction between zones categorized by the nodal prices. This paper deals with a novel network reduction method between zones based on the similarity Index. Line admittances of reduced network were determined by using the least square method. The proposed method was verified by IEEE 39 bus test system.