• Journal of applied mathematics & informatics
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• v.6 no.1
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• pp.1-14
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• 1999

In this paper we shall analyze the fully discrete Galerkin type approximations to solutions of the Rosenau equation. We provide the numerical results of several cases.

• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.1-28
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• 2004

We first apply a first order splitting to a semilinear reaction-diffusion equation and then discretize the resulting system by an $H^1$-Galerkin mixed finite element method in space. This semidiscrete method yields a system of differential algebraic equations (DAEs) of index one. A priori error estimates for semidiscrete scheme are derived for both differ-ential as well as algebraic components. For fully discretization, an implicit Runge-Kutta (IRK) methods is applied to the temporal direction and the error estimates are discussed for both components. Finally, we conclude the paper with a numerical example.

• Journal for History of Mathematics
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• v.28 no.1
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• pp.45-62
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• 2015

This study assumes alternative character of the operation of mathematical club in middle school. The case that operated the voluntary mathematics club for one year was analyzed and the educational effect was considered. First, the examination instrument for choosing the members of mathematics club was developed and used. And, diverse teaching and learning materials for improving creativity and mathematical ability of the members were used. Second, the difference of learning result between the experiment group and control one who joined the activities of mathematics club was analyzed. Finally, mathematical club activity based on mathematics history appeared to be effective in improving academic achievement and mathematics exploration activity.

• Journal of Educational Research in Mathematics
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• v.11 no.2
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• pp.257-271
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• 2001

This study investigated the new revised Mathematics curriculums of elementary schools in Korea and Japan at the end of the 20th century. The comparison was made especially with revising direction, purposes, and contents of elementary school mathematics curriculum in both countries. I began by comparing and confirming the ratio of instruction hours of Mathematics to the total instruction hours of all the subjects at as whole. This comparison was done of the elementary and middle school mathematics. The next part of the study was to compare in detail the purposes of revised mathematics in elementary and middle schools of both countries. Particular attentions was paid to the important revised points of Japanese elementary school Mathematics. Finally, I concluded by comparing the contents of elementary school Mathematics of the two countries. New mathematic text books in both countries having been published by revised curriculum, puts the future task in comparing, in detail, the concrete contents of each textbook.

• Korean Journal of Mathematics
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• v.32 no.1
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• pp.43-57
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• 2024

Given a domain X and a collection H of functions h : X → {0, 1}, the Vapnik-Chervonenkis (VC) dimension of H measures its complexity in an appropriate sense. In particular, the fundamental theorem of statistical learning says that a hypothesis class with finite VC-dimension is PAC learnable. Recent work by Fitzpatrick, Wyman, the fourth and seventh named authors studied the VC-dimension of a natural family of functions ℋ'²_t(E) : 𝔽²_q → {0, 1}, corresponding to indicator functions of circles centered at points in a subset E ⊆ 𝔽²_q. They showed that when |E| is large enough, the VC-dimension of ℋ'²_t(E) is the same as in the case that E = 𝔽²_q. We study a related hypothesis class, ℋ^d_t(E), corresponding to intersections of spheres in 𝔽^d_q, and ask how large E ⊆ 𝔽^d_q needs to be to ensure the maximum possible VC-dimension. We resolve this problem in all dimensions, proving that whenever |E| ≥ C_dq^d-1/(d-1) for d ≥ 3, the VC-dimension of ℋ^d_t(E) is as large as possible. We get a slightly stronger result if d = 3: this result holds as long as |E| ≥ C_3q^7/3. Furthermore, when d = 2 the result holds when |E| ≥ C_2q^7/4.

• Nonlinear Functional Analysis and Applications
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• v.29 no.2
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• pp.451-460
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• 2024

If a₀ + Σⁿ_ν=μ a_νz^ν, 1 ≤ µ ≤ n, is a polynomial of degree n having no zeroin |z| < k, k ≥ 1 and p'(z) its derivative, then Qazi [19] proved $$\max_{{\left|z\right|=1}}\left|p\prime(z)\right|\leq{n}\frac{1+\frac{{\mu}}{n}\left|\frac{a_{\mu}}{a_0} \right|k^{{\mu}+1}}{1+k^{{\mu}+1}+\frac{{\mu}}{n}\left|\frac{a_{\mu}}{a_0} \right|(k^{{\mu}+1}+k^{2{\mu}})}\max_{{\left|z\right|=1}}\left|p(z)\right|$$ In this paper, we not only obtain the L^r version of the polar derivative of the above inequality for r > 0, but also obtain an improved L^r extension in polar derivative.

• Journal of the Chungcheong Mathematical Society
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• v.36 no.2
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• pp.125-133
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• 2023

We establish a characterization theorem of elliptic paraboloids in the (n+1)-dimensional Euclidean space 𝔼ⁿ⁺¹ with extrinsic properties such as the (n+1)-dimensional volumes of regions enclosed by the hyperplanes and hypersurfaces, and the n-dimensional areas of projections of the sections of hypersurfaces cut off by hyperplanes.

• Korean Journal of Mathematics
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• v.30 no.1
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• pp.43-51
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• 2022

The aim of this paper is to obtain a Radau type quadrature formula for a rational interpolation process satisfying the almost quasi Hermite Fejér interpolatory conditions on the zeros of Chebyshev Markov sine fraction on [-1, 1).

• Natural Product Sciences
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• v.27 no.1
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• pp.18-27
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• 2021

Eight cytotoxic constituents, consisting of six triterpenoids, cabralealactone (1), cabraleadiol (2), prototiamin A (3), 23-desmethyllimocin B (5), melianodiol (7) and indicalilacol (8) along with one limonoid, neemfruitins A (4) and one protolimonoid, protoxylocarpin G (6), were isolated from the extract of n-hexane of the stembark of Chisocheton pentandrus. The chemical structures were identified on the basis of spectroscopic evidence and compared to previously reported spectra. These isolated compounds appear for the first time in the plant. Compounds 1 - 8 were evaluated for their cytotoxic effect against MCF-7 breast cancer lines in vitro. Among the isolated compounds, melianodiol (7) showed the strongest cytotoxic activity with IC50 values of 16.8 µM.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.101-123
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• 1998

The purpose of this study is to construct the "open" instructional model that might be used properly in mathematics classroom. In this study, the core philosophy of "openness" in mathematics instruction is looked upon as the transference itself from pursuing simply strengthening the function of instruction such as effectiveness in the management of educational environment into the understanding of the nature of mathematics learning and the pursuing of true effectiveness in mathematics learning. It means, in other words, this study is going to accept the "openness" as functional readiness to open all the possibility among the conditions of educational environment for the purpose of realizing maximum learning effectiveness. With considering these concepts, this study regards open mathematics education as simply one section among the spectrum of mathematics education, thus could be included in the category of mathematics education. The model for open instruction in mathematics classroom, constructed in this study, has the following virtues: This model (1) suggests integrated view of open mathematics instruction that could adjust the individual and sporadic views recently constructed about open mathematics instruction; (2) could suggest structural approach for the construction of open mathematics instruction program; (3) could be used in other way as a method for evaluation open mathematics instruction program.thematics instruction program.