• Korean Journal of Mathematics
• /
• 제25권1호
• /
• pp.37-43
• /
• 2017

We study the existence of positive solutions of second order nonlinear separated boundary value problems of superlinear as well as sublinear type without imposing monotonicity restrictions on the problem. The type of problem investigated cannot be analyzed using the linearization about the trivial solution because either it does not exist (the sublinear case) or is trivial (the superlinear case). The results follow from a known fixed point theorem by noticing that the concavity of the solutions provides an important condition for the applicability of the fixed point result.

• 충청수학회지
• /
• 제23권3호
• /
• pp.511-521
• /
• 2010

In this paper, we define the one-sided fuzzy set and we calculate the mean value and variance, defined by C. Carlsson and R. $Full{\acute{e}}r$, of this fuzzy set. And we obtain a result that, in some special case, the mean of the product of two fuzzy sets is the product of means of each fuzzy sets. This result can be considered as the similar result which is well-known in the independence of events in probability theory.

• 한국수학교육학회지시리즈D:수학교육연구
• /
• 제18권3호
• /
• pp.209-221
• /
• 2014

In the last few decades there has been much interest in how mathematics can be effectively taught and learnt. The Third Wave is a unique ongoing international collaborative mathematics education research project, which aims to explore the relevant values of effective school mathematics teaching from both the teacher and student perspectives. As part of this project, this study investigates the related findings from students on the Chinese mainland. Multiple data were collected through classroom observations, focus group interviews, and written, open-ended questions. Twenty-four students from junior and senior secondary schools were invited to write down their views on an effective lesson, a good mathematics teacher, and how to do well in mathematics learning. Results showed that among the eight values determined in the study, the values of involvement, explanation, and examples were embraced by students across all grades. Students preferred teacher-led mathematics teaching. Junior secondary students placed more value on teachers' personalities, whereas senior students placed more value on teachers' teaching manners.

• Journal of applied mathematics & informatics
• /
• 제22권1_2호
• /
• pp.295-306
• /
• 2006

In this paper, by using the Krasnoselskii fixed point theorem, we study the existence of 2m or 2m + 1 symmetric positive solutions of fourth-order two point boundary value problem y(4)(t) - f(t, y(t), y"(t))= 0, y(0) = y(1) = y'(0) = y"(1)=0.

• Journal of applied mathematics & informatics
• /
• 제27권1_2호
• /
• pp.205-215
• /
• 2009

Sufficient conditions for the existence of at least one solution of the boundary value problems for higher order nonlinear difference equations $\{{{{{\Delta^n}x(i-1)=f(i,x(i),{\Delta}x(i),{\cdots},\Delta^{n-2}x(i)),i{\in}[1,T+1],\atop%20{\Delta^m}x(0)=0,m{\in}[0,n-3],}\atop%20\Delta^{n-2}x(0)=\phi(\Delta^{n-1}(0)),}\atop%20\Delta^{n-1}x(T+1)=-\psi(\Delta^{n-2}x(T+1))}\$. are established.

• Journal of applied mathematics & informatics
• /
• 제33권1_2호
• /
• pp.1-12
• /
• 2015

This paper is concerned with boundary value problems for systems of n-th order dynamic equations on time scales. Under the suitable conditions, the existence and multiplicity of positive solutions are established by using abstract fixed-point theorems.

• Korean Journal of Mathematics
• /
• 제26권1호
• /
• pp.9-21
• /
• 2018

We investigate existence and multiplicity of the solutions for elliptic boundary value problem with two singularities. We obtain one theorem which shows that there exists at least one nontrivial weak solution under some conditions on which the corresponding functional of the problem satisfies the Palais-Smale condition. We obtain this result by variational method and critical point theory.

• Journal of applied mathematics & informatics
• /
• 제31권1_2호
• /
• pp.87-97
• /
• 2013

The purpose of this paper is to employ a new useful technique to solve the initial-Neumann boundary value problems for parabolic, hyperbolic and parabolic-hyperbolic equations and obtain a solution in form of infinite series. The results obtained indicate that this approach is indeed practical and efficient.

• Korean Journal of Mathematics
• /
• 제23권4호
• /
• pp.571-590
• /
• 2015

Let a, b, q be integers with q > 0. The homogeneous Dedekind sum is dened by $$\Large S(a,b,q)={\sum_{r=1}^{q}}\(\({\frac{ar}{q}}\)\)\(\({\frac{br}{q}}\)\)$$, where $$\Large ((x))=\{x-[x]-{\frac{1}{2}},\text{ if x is not an integer},\\0,\hspace{75}\text{ if x is an integer.}$$ In this paper we study the mean value of S(a, b, q) by using mean value theorems of Dirichlet L-functions, and give some asymptotic formula.

• Journal of applied mathematics & informatics
• /
• 제5권3호
• /
• pp.759-770
• /
• 1998

In this paper we use uniform cubic spline polynomials to derive some new consistency relations. These relations are then used to develop a numerical method for computing smooth approxi-mations to the solution and its first second as well as third derivatives for a second order boundary value problem. The proesent method out-performs other collocations finite-difference and splines methods of the same order. numerical illustratiosn are provided to demonstrate the practical use of our method.