• 제목/요약/키워드: mathematics notes

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Two notes on "On soft Hausdorff spaces"

  • El-Shafei, M.E.;Abo-Elhamayel, M.;Al-shami, T.M.
    • Annals of Fuzzy Mathematics and Informatics
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    • 제16권3호
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    • pp.333-336
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    • 2018
  • One of the well known results in general topology says that every compact subset of a Hausdorff space is closed. This result in soft topology is not true in general as demonstrated throughout this note. We begin this investigation by showing that [Theorem 3.34, p.p.23] which proposed by Varol and $Ayg{\ddot{u}}n$ [7] is invalid in general, by giving a counterexample. Then we derive under what condition this result can be generalized in soft topology. Finally, we evidence that [Example 3.22, p.p. 20] which introduced in [7] is false, and we make a correction for this example to satisfy a condition of soft Hausdorffness.

Some Notes on the Fourier Series of an Almost Periodic Weakly Stationary Process

  • You, Hi-Se
    • Journal of the Korean Statistical Society
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    • 제3권1호
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    • pp.13-16
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    • 1974
  • In my former paper [3] I defined an almost periodicity of weakly sationary random processes (a.p.w.s.p.) and presented some basic results of it. In this paper I shall present some notes on the Fourier series of an a.p.w.s.p., resulting from [3]. All the conditions at the introduction of [3] are assumed to hold without repreating them here. The essential facts are as follows : The weakly stationary process $X(t,\omega), t\in(-\infty,\infty), \omega\in\Omega$, defined on a probability space $(\Omega,a,P)$, has a spectral representation $$X(t,\omega)=\int_{-\infty}^{infty}{e^{it\lambda\xi}(d\lambda,\omega)},$$ where $\xi(\lambda)$ is a random measure. Then, the continuous covariance $\rho(\mu) = E(X(t+u) X(t))$ has the form $$\rho(u)=\int_{-\infty}^{infty}{e^{iu\lambda}F(d\lambda)},$$ $E$\mid$\xi(\lambda+0)-\xi(\lambda-0)$\mid$^2 = F(\lambda+0) - F(\lambda-0) \lambda\in(-\infty,\infty)$, assumimg that $\rho(u)$ is a uniformly almost periodic function.

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수학교사 연수에서 협력적 멘토링의 실제 -'함께 만들어가는 수학교사 연수'의 사례를 중심으로- (Collaborative mentoring in professional development program for mathematics teachers: A case of "PD program of multi-tiered teacher community")

  • 조형미;권오남;이지연;윤정은
    • 한국수학교육학회지시리즈A:수학교육
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    • 제54권3호
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    • pp.283-298
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    • 2015
  • This research is the case study of collaborative mentoring in the professional development of multi-tiered mathematics teacher community. We observed the procedures of mentoring, and contents of mentoring in PD program. For this purpose, we implemented PD program with participant unit composed of 3 or 4 teachers in the same school and total 25 teachers from 4 elementary schools and 4 high schools. Also there were 1 mentor and 1 sub-mentor to support each school. Observed mentoring processes were all recorded and the participants not only were interviewed several times but also wrote reflection notes after meetings. While mentoring PD program was implemented, mentor and mentee had joint responsibility about lessons implemented by mentee. Furthermore It showed possibility of change of teacher learning culture, learning culture of community. It means that teacher would improve their professionalism more effectively within teacher community instead of individual. 4 reflection contents was founded in collaborative mentring; 1)purpose of mathematics education, 2)motivation and connection between previous lecture and present lecture 3)lack of mathematical contents in lesson 4)discourse between teacher and students.

NOTES ON CRITICAL ALMOST HERMITIAN STRUCTURES

  • Lee, Jung-Chan;Park, Jeong-Hyeong;Sekigawa, Kouei
    • 대한수학회보
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    • 제47권1호
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    • pp.167-178
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    • 2010
  • We discuss the critical points of the functional $F_{\lambda,\mu}(J,g)=\int_M(\lambda\tau+\mu\tau^*)d\upsilon_g$ on the spaces of all almost Hermitian structures AH(M) with $(\lambda,\mu){\in}R^2-(0,0)$, where $\tau$ and $\tau^*$ being the scalar curvature and the *-scalar curvature of (J, g), respectively. We shall give several characterizations of Kahler structure for some special classes of almost Hermitian manifolds, in terms of the critical points of the functionals $F_{\lambda,\mu}(J,g)$ on AH(M). Further, we provide the almost Hermitian analogy of the Hilbert's result.

Vortex Filament Equation and Non-linear Schrödinger Equation in S3

  • Zhang, Hongning;Wu, Faen
    • Kyungpook Mathematical Journal
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    • 제47권3호
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    • pp.381-392
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    • 2007
  • In 1906, da Rios, a student of Leivi-Civita, wrote a master's thesis modeling the motion of a vortex in a viscous fluid by the motion of a curve propagating in $R^3$, in the direction of its binormal with a speed equal to its curvature. Much later, in 1971 Hasimoto showed the equivalence of this system with the non-linear Schr$\ddot{o}$dinger equation (NLS) $$q_t=i(q_{ss}+\frac{1}{2}{\mid}q{\mid}^2q$$. In this paper, we use the same idea as Terng used in her lecture notes but different technique to extend the above relation to the case of $R^3$, and obtained an analogous equation that $$q_t=i[q_{ss}+(\frac{1}{2}{\mid}q{\mid}^2+1)q]$$.

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Notes on "Perpetual Question" of Problem Solving: How Can Learners Best Be Taught Problem-Solving Skills?

  • Oleksiy, Yevdokimov;Peter, Taylor
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제12권3호
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    • pp.179-191
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    • 2008
  • Although problem solving was a major focus of mathematics education research in many countries throughout the 1990s, not enough is known about how people best acquire problem-solving skills. This paper is an attempt to advance further development of problem-solving skills of talented school students through combination of some methods accessible from curriculum knowledge and more special techniques that are beyond curriculum. Analysis of various problems is provided in detail. Educational aspects of challenging problems in mathematical contests up to IMO level are, also, taken into account and discussed in the paper.

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NOTES ON GENERALIZED FIBONACCI NUMBERS AND MATRICES

  • Halim, Ozdemir;Sinan, Karakaya;Tugba, Petik
    • 호남수학학술지
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    • 제44권4호
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    • pp.473-484
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    • 2022
  • In this study, some new relations between generalized Fibonacci numbers and matrices are given. The work is designed in three stages: Firstly, it is obtained a relation between generalized Fibonacci numbers and integer powers of the matrices X satisfying the relation X2 = pX +qI, and also, many results are derived from obtained relation. Then, it is established more general relation between generalized Fibonacci numbers and the square matrices X satisfying the condition X2 = VnX - (-q)nI. Finally, some applications and numerical examples related to the obtained results are given.

Middle School Mathematics Teachers' Responses to a Student's Mistaken Mathematical Conjecture and Justification

  • Kim, Young-Ok
    • East Asian mathematical journal
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    • 제29권2호
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    • pp.109-135
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    • 2013
  • The purpose of the study was to investigate the reality of middle school mathematics teachers' subject matter knowledge for teaching mathematical conjecture and justification. Data in the study were collected through interviewing nine Chinese and ten Korean middle school mathematics teachers. The teachers responded to the question that was designed in the form of a scenario that presents a teaching task related to a geometrical topic. The teachers' oral responses were audiotaped and transcribed, and their written notes were collected. The results of the study were compared to the analysis of American and Chinese elementary and secondary teachers' responses to the same task in Ball (1988) and Ma (1999). The findings of the study suggested that teachers' approaches to explaining and demonstrating a mathematical topic were significantly influenced by their knowledge of learners and knowledge of the curriculum they teach. One of the practical implications of the study is that teachers should recognize the advantages of learning the conceptual structure of a mathematical topic. It allows the teachers to have the flexibility to come up with meaningful mathematical approaches to teaching the topic, which are comprehensible to the learners whatever the grade levels they teach, rather than rule-based algorithms.

NOTES ON ${\overline{WN_{n,0,0_{[2]}}}$ I

  • CHOI, SEUL HEE
    • 호남수학학술지
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    • 제27권4호
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    • pp.571-581
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    • 2005
  • The Weyl-type non-associative algebra ${\overline{WN_{g_n,m,s_r}}$ and its subalgebra ${\overline{WN_{n,m,s_r}}$ are defined and studied in the papers [8], [9], [10], [12]. We will prove that the Weyl-type non-associative algebra ${\overline{WN_{n,0,0_{[2]}}}$ and its corresponding semi-Lie algebra are simple. We find the non-associative algebra automorphism group $Aut_{non}({\overline{WN_{1,0,0_{[2]}}})$.

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NOTES ON ${\overline{WN_{n,0,0_{[2]}}}$ II

  • CHOI, SEUL HEE
    • 호남수학학술지
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    • 제27권4호
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    • pp.583-593
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    • 2005
  • The Weyl-type non-associative algebra ${\overline{WN_{g_n,m,s_r}}$ and its subalgebra ${\overline{WN_{n,m,s_r}}$ are defined and studied in the papers [2], [3], [9], [11], [12]. We find the derivation group $Der_{non}({\overline{WN_{1,0,0_{[2]}}})$ the non-associative simple algebra ${\overline{WN_{1,0,0_{[2]}}}$.

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