• Title/Summary/Keyword: Symmetry number

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Reliability for Multiple Reviewers by using Loglinear Models (로그선형모형을 이용한 복수 평가자들간의 신뢰도에 관한 연구)

  • Park, Byung-Joo;Lee, Sung-Im;Lee, Young-Jo;Kim, Dong-Hyun;Kwon, Ho-Jang;Bae, Jong-Myon;Shin, Myung-Hee;Ha, Mi-Na;Han, Sang-Whan
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.4 s.59
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    • pp.719-728
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    • 1997
  • To guarantee the inter-reviewer reliability is very important in evaluating the quality of large number of clinical research papers by multiple reviewers. We cannot find reports on statistical methods for evaluating reliability for multiple raters in clinical research field. The purpose of this paper is to introduce the statistical methods focused on kappa statistic and five kinds of loglinear models for, which can be applied when evaluating the reliability of multiple raters. We have applied these methods to the result of a project, in which seven reviewers have evaluated the quality of 33 papers with regard to four aspects of paper contents including study hypothesis, study design, study population, study method, data analysis and interpretation. Among the five loglinear models including Symmetry model, Conditional symmetry model, Quasi-symmetry model, Independence model, and Quasi-independence model, Quasi-symmetry model shows the best model of fitting. And the level of reliability among seven reviewers revealed to be acceptable as meaningful.

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Using Higher Order Neuron on the Supervised Learning Machine of Kohonen Feature Map (고차 뉴런을 이용한 교사 학습기의 Kohonen Feature Map)

  • Jung, Jong-Soo;Hagiwara, Masafumi
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.5
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    • pp.277-282
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    • 2003
  • In this paper we propose Using Higher Order Neuron on the Supervised Learning Machine of the Kohonen Feature Map. The architecture of proposed model adopts the higher order neuron in the input layer of Kohonen Feature Map as a Supervised Learning Machine. It is able to estimate boundary on input pattern space because or the higher order neuron. However, it suffers from a problem that the number of neuron weight increases because of the higher order neuron in the input layer. In this time, we solved this problem by placing the second order neuron among the higher order neuron. The feature of the higher order neuron can be mapped similar inputs on the Kohonen Feature Map. It also is the network with topological mapping. We have simulated the proposed model in respect of the recognition rate by XOR problem, discrimination of 20 alphabet patterns, Mirror Symmetry problem, and numerical letters Pattern Problem.

Analysis of Coordination Ambiguity in Korean (한국어 병렬문의 중의성 분석)

  • 이호동;박종철
    • Language and Information
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    • v.7 no.2
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    • pp.59-79
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    • 2003
  • Coordination in natural language is often syntactically explained by the rule schema X \longrightarrow X′ and X", where X′ and X" refer to expressions of a like syntactic type. While this schema does explain a lot of instances of coordination, it is well known that this schema also gives rise to serious structural ambiguity, leading not only to numerous unintended interpretations but also to a high degree of unnecessary computational complexity. In order to identify intended interpretations, we need to take into account a number of clues at all the levels of morphology, syntax, semantics, and pragmatics/discourse. In this paper, we propose, with an accompanying data analysis, principles of symmetry and coherency for an effective and reasonable identification of intended interpretations from coordination-bearing sentences.

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Ideal Classes and Cappell-Shaneson Homotopy 4-Spheres

  • Min Hoon Kim;Shohei Yamada
    • Kyungpook Mathematical Journal
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    • v.63 no.3
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    • pp.373-411
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    • 2023
  • Gompf proposed a conjecture on Cappell-Shaneson matrices whose affirmative answer implies that all Cappell-Shaneson homotopy 4-spheres are diffeomorphic to the standard 4-sphere. We study Gompf conjecture on Cappell-Shaneson matrices using various algebraic number theoretic techniques. We find a hidden symmetry between trace n Cappell-Shaneson matrices and trace 5 - n Cappell-Shaneson matrices which was suggested by Gompf experimentally. Using this symmetry, we prove that Gompf conjecture for the trace n case is equivalent to the trace 5 - n case. We confirm Gompf conjecture for the special cases that -64 ≤ trace ≤ 69 and corresponding Cappell-Shaneson homotopy 4-spheres are diffeomorphic to the standard 4-sphere. We also give a new infinite family of Cappell-Shaneson spheres which are diffeomorphic to the standard 4-sphere.

Uptake Effects of Two Electrons for Relative Stability and Atomic Structures of Carbon Cluster Isomers of C20: ab initio Methods

  • Lee, Wang-Ro;Lee, Chang-Hoon;Kang, Jin-Hee;Park, Sung-Soo;Hwang, Yong-Gyoo;Lee, Kee-Hag
    • Bulletin of the Korean Chemical Society
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    • v.30 no.2
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    • pp.445-448
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    • 2009
  • This study examined the effect of the uptake of one and two electrons on the atomic structure of three isomers of $C_{20}$ clusters, namely the ring, bowl (corannulene like), and cage (the smallest fullerene). Geometry optimizations were performed using the hybrid density functional (B3LYP) methods for neutral, singly and doubly charged $C_{20},\;{C_{20}}^-,and\;{C_{20}}^{2-}$. These results show that the symmetry of the lowest energies for ring and bowl isomers were not changed, whereas the increasing order of energy for the cage (the smallest fullerene) isomers was changed from $D_{2h}\;<\;C_{2h}\;{\leq}\;C_2\;of\;C_{20}\;through\;Ci\;<\;C_{2h}\;<\;C_2\;<\;D_{2h}\;of\;{C_{20}}^-\;to\;Ci\;<\;C_2\;<\;D_{2h}\;<\;C_{2h}\;of\;{C_{20}}^{2-}$. The reduced symmetry isomers of the cage have comparative energy and the ground state symmetry of the neutral and single and double charged $C_{20}$ decreased with increasing number of electrons taken up in the point of energetics. Interestingly, the difference in energy between the ground state and the next higher energy state of ${C_{20}}^{2-}$ was 3.5kcal/mol, which is the largest energy gap of the neutral, single anion and double anion of the cage isomers examined.

Numerical Study of Wavy Taylor-Couette Flow(I) -Without an Axial Flow- (Wavy Taylor-Couette 유동에 대한 전산해석 (I) -축방향 유동이 없는 경우-)

  • Hwang, Jong-Yeon;Yang, Gyeong-Su
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.5
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    • pp.697-704
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    • 2001
  • The flow between two concentric cylinders, with the inner one rotating, is studied using numerical simulation. This study considers the identical flow geometry as in the experiments of Wereley and Lueptow[J. Fluid Mech., 364, 1998]. They carried out experiment using PIV to measure the velocity fields in a meridional plane of the annulus in detail. When Taylor number increases over the critical one, the flow instability caused by curved streamlines of the tangential flow induces Taylor vortices in the flow direction. As Taylor number further increases over another critical one, the steady Taylor vortices become unsteady and non-axisymmetrically wavy. The velocity vector fields obtained also show the same flow features found in the experiments of Wereley and Lueptow.

A Study on the Bending Analysis of Rectangular Plates by Substructuring Technique (분할구조기법을 이용한 장방형판의 휨해석에 관한 연구)

  • 오숙경;김성용;김일중;이용수
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1997.10a
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    • pp.65-72
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    • 1997
  • This study is the bending analysis of rectangular plates with 4-sides simply supported by Finite Element Method using substructuring technique. In finite element method, as the more number of finite element, the more dimension of matrix, it is difficult to obtain accuracy solution. In this paper substructuring technique is applied to finite element method in order to reduce the dimension of matrix according to the number of finite element mesh. To validate finite element method using substructuring technique, deflections and moments of rectangular plates by that method is compared with those of references. Considering the symmetry of the plate and load, one fourth of plate is analyzed. Operating time and the error of solutions according to the number of finite element mesh and substructure are compared with each other.

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REVISION OF THE THEORY OF SYMMETRIC ONE-STEP METHODS FOR ORDINARY DIFFERENTIAL EQUATIONS

  • Kulikov, G.Yo.
    • Journal of applied mathematics & informatics
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    • v.5 no.3
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    • pp.669-690
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    • 1998
  • In this paper we develop a new theory of adjoint and symmetric method in the class of general implicit one-step fixed-stepsize methods. These methods arise from simple and natral def-initions of the concepts of symmetry and adjointness that provide a fruitful basis for analysis. We prove a number of theorems for meth-ods having these properties and show in particular that only the symmetric methods possess a quadratic asymptotic expansion of the global error. In addition we give a very simple test to identify the symmetric methods in practice.

Investigation of Geoboards in Elementary Mathematics Education (초등수학에서 기하판 활용방안 탐색)

  • 김민경
    • Education of Primary School Mathematics
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    • v.5 no.2
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    • pp.111-119
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    • 2001
  • Over the years, the benefits of instructional manipulatives in mathematics education have been verified by classroom practice and educational research. The purpose of this paper is to introduce how the instructional material, specifically, geoboard could be used and integrated in elementary mathematics classroom in order to develop student's mathematical concepts and process in terms of the following areas: (1) Number '||'&'||' Operation : counting, fraction '||'&'||' additio $n_traction/multiplication (2) Geometry : geometric concepts (3) Geometry : symmetry '||'&'||' motion (4) Measurement : area '||'&'||' perimeter (5) Probability '||'&'||' Statistics : table '||'&'||' graph (6) Pattern : finding patterns Further, future study will continue to foster how manipulatives will enhance children's mathematics knowledge and influence on their mathematics performance.

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Recognizing asymmetric moire patterns for human spinal deformity detection

  • Kim, Hyoung-Seop;Hiroshi UENO;Seiji ISHIKAWA;Yoshinori Otsuka
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.568-571
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    • 1997
  • Recently, the number of techniques for analyzing medical images has been increasing in computer vision, employing X-ray CT images, ultrasound images, MR images, moire topographic images, etc. Spinal deformity is a serious problem especially for teenagers and medical doctors inspect moire topographic images of their backs visually for the primary screening. If a subject is normal, the moire image is almost symmetric with respect to the middle line of the subject's back, otherwise it shows asymmetric shape. In this paper, an image analysis technique is described for discriminating suspicious cases from normal in human spinal deformity by recognizing asymmetric moire images of human backs. The principal axes which are sensitive to asymmetry of the moire image are extracted at two parts on a subject's back and their angles are evaluated with respect to the detected middle line of the back. The two angles compose a 2-D feature space and inspected cases are divided into two clusters in the space by a linear discriminant function based on the Mahalanobis distance. Given 120 cases, 60 normal and 60 abnormal, the leave-out method was applied for the recognition and 75% recognition rate was achieved.

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