• Title/Summary/Keyword: Rank Deficiency

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REMARKS ON CRITERIA FOR THE EXISTENCE OF A POSITIVE EQUILIBRIUM IN REACTION NETWORKS

  • Choo, S.M.
    • Journal of applied mathematics & informatics
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    • v.29 no.3_4
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    • pp.949-953
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    • 2011
  • It is interesting to know the behavior of a network from its structure. One interesting topic is to find a relation between the existence of a positive equilibrium of the reaction network and its structure. One approach to study this topic is using the concept of deficiency. Another is using some conditions on nodes, which can apply to large-size networks compared to deficiency. In this work, we show the relation between deficiency and the conditions.

A function space approach to study rank deficiency and spurious modes in finite elements

  • Sangeeta, K.;Mukherjee, Somenath;Prathap, Gangan
    • Structural Engineering and Mechanics
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    • v.21 no.5
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    • pp.539-551
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    • 2005
  • Finite elements based on isoparametric formulation are known to suffer spurious stiffness properties and corresponding stress oscillations, even when care is taken to ensure that completeness and continuity requirements are enforced. This occurs frequently when the physics of the problem requires multiple strain components to be defined. This kind of error, commonly known as locking, can be circumvented by using reduced integration techniques to evaluate the element stiffness matrices instead of the full integration that is mathematically prescribed. However, the reduced integration technique itself can have a further drawback - rank deficiency, which physically implies that spurious energy modes (e.g., hourglass modes) are introduced because of reduced integration. Such instability in an existing stiffness matrix is generally detected by means of an eigenvalue test. In this paper we show that a knowledge of the dimension of the solution space spanned by the column vectors of the strain-displacement matrix can be used to identify the instabilities arising in an element due to reduced/selective integration techniques a priori, without having to complete the element stiffness matrix formulation and then test for zero eigenvalues.

AN ELEMENTARY PROOF OF THE EXISTENCE OF A POSITIVE EQUILIBRIUM IN REACTION NETWORKS

  • Choo, S.M.
    • Journal of applied mathematics & informatics
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    • v.28 no.5_6
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    • pp.1545-1552
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    • 2010
  • It is interesting to know the behavior of a network from its structure. One interesting topic is to find a relation between the existence of a positive equilibrium of the reaction network and its structure. One approach to study this topic is using the concept of deficiency. In this work, we develop an algorithm and show an elementary proof of the relation based on the algorithm and deficiency.

AN EXAMPLE OF LARGE GROUPS

  • Cevik, Ahmet Sinan
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.1
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    • pp.195-206
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    • 2020
  • The fundamental idea of this article is to present an effective way to obtain the large groups in terms of the split extension obtained by a finite cyclic group and a free abelian group rank 2. The proof of the main result on largeness property of this specific split extension groups will be given by using the connection of large groups with the groups having deficiency one presentations.

A GRAPHICAL ALGORITHM FOR CALCULATING THE RANKS OF COMPLEX REACTION NETWORKS

  • Choo, S.M.;Lee, N.Y.
    • Journal of applied mathematics & informatics
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    • v.30 no.5_6
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    • pp.787-792
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    • 2012
  • We present a graphical algorithm and theorems for calculating the ranks of reaction networks. The ranks are needed to study behaviors of the networks from their structures. This approach can graphically simplify complex networks for the calculation. We show an example of a large network for the practical advantage.

On the Fitting ANOVA Models to Unbalanced Data

  • Jong-Tae Park;Jae-Heon Lee;Byung-Chun Kim
    • Communications for Statistical Applications and Methods
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    • v.2 no.1
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    • pp.48-54
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    • 1995
  • A direct method for fitting analysis-of-variance models to unbalanced data is presented. This method exploits sparsity and rank deficiency of the matrix and is based on Gram-Schmidt orthogonalization of a set of sparse columns of the model matrix. The computational algorithm of the sum of squares for testing estmable hyphotheses is given.

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The Optimized Integration of Single-baseline GPS Solutions for Network-based Kinematic Positioning (네트워크 기반 키너매틱 위치결정을 위한 단일기선 GPS해의 최적 결합)

  • Choi, Yun-Soo;Bae, Tae-Suk;Lee, Jong-Ki;Kwon, Jay-Hyoun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.3
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    • pp.207-213
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    • 2007
  • For several years, although the demand of high accuracy kinematic positing using multiple bases has been increased, most of the commercial GPS processing softwares can provide the single-baseline solutions only. Thus, we studied the methods to improve the accuracy of the kinematic positioning using the network configuration based on the several single-baseline solutions. As discussed in this study, the positioning accuracy as well as the network stability is improved by introducing the geodetic network adjustment theories into the kinematic positioning application. Three different methods to remove the rank-deficiency, RLESS, BLIMPBE and SCLESS, are analyzed in this study. The 3D RMS error has been improved from 3.5cm(max) to 2.1cm using the network-based kinematic positioning, and it is desired to choose BLIMPBE and SCLESS depending on the accuracy of the base stations.

Construction Algorithm of Grassmann Space Parameters in Linear Output Feedback Systems

  • Kim Su-Woon
    • International Journal of Control, Automation, and Systems
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    • v.3 no.3
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    • pp.430-443
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    • 2005
  • A general construction algorithm of the Grassmann space parameters in linear systems - so-called, the Plucker matrix, 'L' in m-input, p-output, n-th order static output feedback systems and the Plucker matrix, $'L^{aug}'$ in augmented (m+d)-input, (p+d)-output, (n+d)-th order static output feedback systems - is presented for numerical checking of necessary conditions of complete static and complete minimum d-th order dynamic output feedback pole-assignments, respectively, and also for discernment of deterministic computation condition of their pole-assignable real solutions. Through the construction of L, it is shown that certain generically pole-assignable strictly proper mp > n system is actually none pole-assignable over any (real and complex) output feedbacks, by intrinsic rank deficiency of some submatrix of L. And it is also concretely illustrated that this none pole-assignable mp > n system by static output feedback can be arbitrary pole-assignable system via minimum d-th order dynamic output feedback, which is constructed by deterministic computation under full­rank of some submatrix of $L^{aug}$.

A Study for the Development of the Fundamental Nursing Practice Education -Focused on A Nursing College - (기본간호실습교육의 발전을 위한 일 연구 -일 지역의 3년제 간호대학을 중심으로-)

  • Je Mi-Soon
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.6 no.2
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    • pp.331-346
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    • 1999
  • Many studies have reported that a lot of nursing colleges do not have good facilities for the nursing practice in hospitals, so many students do not have the good ability which is needed to be a competent nurse. The purpose of this study was to develop a program in which students could improve their ability in fundamental nursing skills before the graduation. This study was primarily designed to identify items of the fundamental nursing practice in which nursing college students have perceived deficiencies. According to previous studies, a total 75 items were presented. In Identifying them, a modified Porter format was used. The questionnaire contained three sections. A. How well do you think you can/could perform the item when you graduate/graduated the college? B. How well do you think you should perform/should be able to perform the item when you graduate/graduated the college? C. How important do you think the item is? For each of the 75 items, the respondents were instructed to answer the above three questions, by circling a number on a rating scale extending from 1 to 5, where low numbers represented a low degree of performance or minimum amount, and high numbers represented a high degree of performance or maximum amount. The perceived degree of deficiency in performance on each questionnaire item was obtained by subtracting the answer to Part A of an item from that to of Part B. The larger difference means a larger perceived degree of deficiency in performance. This method of measuring the perceived degree of deficiency in performance is an indirect measure derived from two direct answers by the respondent for each item. From this result Part C of each item was used to rank the items, and the items were prioritized. The items which had the highest priority were IV injection, simple catheterization, indwelling catheterization, CPR, and nurse recording. By this method, through these results from a nursing college, and the items which will be used first in developing the supplementation program for nursing college students can be identified.

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Finite Element Model Updating of Framed Structures Using Constrained Optimization (구속조건을 가진 최적화기법을 이용한 골조구조물의 유한요소모델 개선기법)

  • Yu, Eun-Jong;Kim, Ho-Geun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.446-451
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    • 2007
  • An Improved finite element model updating method to address the numerical difficulty associated with ill-conditioning and rank-deficiency. These difficulties frequently occur in model updating problems, when the identification of a larger number of physical parameters is attempted than that warranted by the information content of the experimental data. Based on the standard Bounded Variables Least-squares (BVLS) method, which incorporates the usual upper/lower-bound constraints, the proposed method is equipped with new constraints based on the correlation coefficients between the sensitivity vectors of updating parameters. The effectiveness of the proposed method is investigated through the numerical simulation of a simple framed structure by comparing the results of the proposed method with those obtained via pure BVLS and the regularization method. The comparison indicated that the proposed method and the regularization method yield approximate solutions with similar accuracy.

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