• Title/Summary/Keyword: group theory

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The Effects of the Play with Multiplication Activities Based on Skemp's Theory on Mathematics Achievements and Attitudes towards Mathematics (Skemp 이론에 따른 곱셈 놀이활동이 수학학업성취도 및 수학적 태도에 미치는 효과)

  • Park, Man-Goo;Park, Kyeong-Seon
    • Journal of the Korean School Mathematics Society
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    • v.12 no.3
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    • pp.211-230
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    • 2009
  • The purpose of this study was to investigate the effects of using the play with multiplication activities based on Skemp's theory for mathematics achievements and attitudes toward mathematics of elementary school students. For this study, we rearranged Skemp's play activities according to our curriculum in the area of multiplication and applied them to the 2nd grade classes of an elementary school. The plays with multiplication activities were applied to the experimental group while traditional teaching method was used with the current mathematics textbook for the comparative group. We obtained the following conclusions: First, in terms of mathematics achievement, the experimental group who used the plays with multiplication activities based on Skemp's theory didn't show significant difference with the comparative group. Second, it proved that the plays with multiplication activities based on Skemp's theory was more effective for lower level of students than the higher level of students. Third, the plays with multiplication activities based on Skemp's theory have positive effects on improving students' attitudes toward mathematics. We need to use the plays with multiplication activities based on Skemp's theory in the classrooms and find problems with the applying the activities. In addition, we need to develop a more various activities based on Skemp's theory for a better teaching.

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The Historical Background of Erlangen Program (에를랑겐 프로그램의 성립 배경)

  • Han, Kyeong Hye
    • Journal for History of Mathematics
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    • v.26 no.4
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    • pp.233-243
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    • 2013
  • The Erlangen program is a scholastic plan by German mathematician Felix Klein, in which he, based on group theory, made a reassessment of geometry as well as an attempt to generally organize it. In this paper, I will introduce the historical and scholastic background of the Erlangen program, overview the process of its formation, and provide some comments regarding its historical significance.

ELEMENTARY TOPICS ON WEAK POLYGROUPS

  • Davvaz, B.
    • Bulletin of the Korean Mathematical Society
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    • v.40 no.1
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    • pp.1-8
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    • 2003
  • In this paper, we further develop the weak polygroup theory, we define quotient weak polygroup and then the fundamental homomorphism theorem of group theory is derived in the context of weak polygroups. Also, we consider the fundamental relation $\beta$$^{*}$ defined on a weak polygroup and define a functor from the category of all weak polygroups into the category of all fundamental groups.s.

ON SPIN ALTERNATING GROUP ACTIONS ON SPIN 4-MANIFOLDS

  • Kiyono, Kazuhiko;Liu, Ximin
    • Journal of the Korean Mathematical Society
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    • v.43 no.6
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    • pp.1183-1197
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    • 2006
  • Let X be a smooth, closed, connected spin 4-manifold with $b_1(X)=0$ and signature ${\sigma}-(X)$. In this paper we use Seiberg-Witten theory to prove that if X admits a spin alternating $A_4$ action, then $b^+_2(X)$ ${\geq}$ |${\sigma}{(X)}$|/8+3 under some non-degeneracy conditions.

분포매개정수를 갖는 원자로의 최적제어 2

  • 지창열
    • 전기의세계
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    • v.29 no.4
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    • pp.256-259
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    • 1980
  • A singular pertubation theory is applied to obtain an approximate solution for suboptimal control of nuclear reactors with spatially distributed parameters. The inverse of the neutron velocity is regarded as a small perturbing parameter, and the model, adopted for simplicity, is a cylindrically symmetrical reactor whose dynamics are described by the one group diffusion equation with one delayed neutron group. The Helmholtz mode expansion is used for the application of the optimal theory for lumped parameter systems to the spatially distributed parameter systems. An asymptotic expansion of the feedback gain matrix is obtained with construction of the boundary layer correction up to the first order.

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Spin-Orbit Density Functional Theory Calculations for TlAt with Relativistic Effective Core Potentials

  • Choi, Yoon-Jeong;Bae, Cheol-Beom;Lee, Yoon-Sup;Lee, Sang-San
    • Bulletin of the Korean Chemical Society
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    • v.24 no.6
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    • pp.728-730
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    • 2003
  • Bond lengths, harmonic vibrational frequencies and dissociation energies of TlAt are calculated at ab initio molecular orbital and density functional theory using effective spin-orbit operator and relativistic effective core potentials. Spin-orbit effects estimated from density functional theory are in good agreement with those from ab initio calculations, implying that density functional theory with effective core potentials can be an efficient and reliable methods for spin-orbit interactions. The estimated $R_e$, $ω_e$ and $D_e$ values are 2.937 ${\AA}$, 120 $cm^{-1}$, 1.96 eV for TlAt. Spin-orbit effects generally cause the bond contraction in Group 13 elements and the bond elongation in the Group 17 elements, and spin-orbit effects on Re of TlAt are almost cancelled out. The spinorbit effects on $D_e$ of TlAt are roughly the sum of spin-orbit effects on $D_e$ of the corresponding element hydrides. Electron correlations and spin-orbit effects are almost additive in the TlAt molecule.

Effects of Rice Straw (RS) on Allergic Contact Dermatitis (ACD) Induced by DNCB in Mice (볏집 도초(稻草)이 DNCB로 유발된 생쥐의 알레르기성 접촉성 피부염에 미치는 영향)

  • Park, Jem Ma;Chae, Joong Won
    • The Journal of Pediatrics of Korean Medicine
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    • v.27 no.4
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    • pp.39-49
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    • 2013
  • Objectives In the theory of Korean medicine, rice straw (RS) has been used effectively as treatments for dyspepsia, diarrhea, enteritis, inflammatory epigastric diseases and various dermatitis. However, the theory has not been studied intensively yet about anti-inflammatory effects for human. This study was to investigate effects of RS for a treatment of allergic contact dermatitis (ACD) induced by 2,4-dinitrochlorobezene (DNCB) in mice. Methods In this experiment, effects of RS were investigated on changes in body weights, dorsum skin thickness, clinical aspects on the dorsum skin, spleen and body weight among these four groups; normal group (NOR), control group (CON), RS spread group (RSS) and RS spread and administer group (RSS+Adm). In addition, the effects on proliferations of splenocytes were also investigated in vitro and in vivo study. Results RSS group and RSS+Adm group showed increasing in body weights, diminished dorsum skin thickness and treated dermatitis on dorsum skin. In RSS+Adm group, spleen weights were lowered significantly compared to CON group. Conclusions In conclusion, these data suggest that RS can decrease symptoms of ACD significantly, and it shows the anti-inflammatory and immunosuppressant effect as well. Therefore, RS can be useful to treat patients with ACD.

Effects of Integrated Menopause Management Program for Middle Aged Woman (중년여성의 통합적 폐경관리 프로그램의 효과)

  • Park, Jung-Suk;Lee, Young-Eun
    • Women's Health Nursing
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    • v.17 no.1
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    • pp.10-20
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    • 2011
  • Purpose: The purpose of this study was to examine the effects of integrated menopause management program derived theoretical framework of King (1981)'s goal attainment theory model for middle aged women. Methods: This research was a nonequivalent control group non-synchronized design. The subjects of this study were 37 middle aged women in Busan and experiencing menopause; 17 for the experimental group and 20 for the control group. Experimental group was educated for 1 hour group interchange activity and five minutes individual interchange activity, once a week during 8 weeks. Measurement for comparison were taken two times, at baseline, 8wks. The effects were evaluated with menopause symptom, menopause knowledge, menopause attitude and menopause management. Results: The experimental group was significantly lower than control group on menopause symptom (F=5.936, p=.010) and higher than control group on menopause knowledge (F=12.031, p=.001) and menopause management (F=5.861, p=.010) after integrated menopause management program. However integrated menopause management program did not make significant differences on menopause attitude (F=0.105, p=.374). Conclusion: Results indicate that integrated menopause management program could be an effective intervention decreasing menopause symptom and for increasing menopause knowledge, menopause management in middle aged women.

An Elementary Study on the Combustion Mechanism of Levitated Droplet Clusters by Ultrasonic Wave (초음파를 이용한 부상유적군의 연소기구에 관한 기초연구)

  • Jung, Jin-Do;Kim, Seung-Mo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.8
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    • pp.1191-1199
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    • 2003
  • This paper describes to observe the combustion process of only one droplet cluster. In this study, liquid fuel was atomized by ultrasonic wave to form an acoustically levitated droplet cluster. In order to elucidate the detailed structure of burning process of the droplet cluster, laser tomography method was applied. Time-series planar images of fuel droplets were processed and diameter of the each droplet was calculated based on the Mie-scattering theory. Using these data, the modified droplet group combustion number was estimated in time-series. As the result, when the internal droplet group combustion occur, the modified group combustion number dose not decrease monotonically, but show a tow-staged decreasing process. In all case of combustion process, combustion reactions were measured two types that combustion speed was fast and slow. It was casued by difference of concentration degree and droplet size distribution.

TRIVIALITY OF A TRACE ON THE SPACE OF COMMUTING TRACE-CLASS SELF-ADJOINT OPERATORS

  • Myung, Sung
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.6
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    • pp.1205-1211
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    • 2010
  • In the present article, we investigate the possibility of a real-valued map on the space of tuples of commuting trace-class self-adjoint operators, which behaves like the usual trace map on the space of trace-class linear operators. It turns out that such maps are related with continuous group homomorphisms from the Milnor's K-group of the real numbers into the additive group of real numbers. Using this connection, it is shown that any such trace map must be trivial, but it is proposed that the target group of a nontrivial trace should be a linearized version of Milnor's K-theory as with the case of universal determinant for commuting tuples of matrices rather than just the field of constants.