• Journal of applied mathematics & informatics
• /
• v.25 no.1_2
• /
• pp.353-361
• /
• 2007

In this paper, we prove the existence of multiple solutions for Neumann and periodic problems. Our main tools are recent general multiplicity theorems proposed by B. Ricceri.

• Journal of applied mathematics & informatics
• /
• v.7 no.2
• /
• pp.693-701
• /
• 2000

In this paper, we investigate a generalization of the Ulam stability problem of the 3-dimensional Euler-Lagrange functional equation f(x-y-z)+f(x)+f( y)+f(z)= f(x-y) +f(y+z) +f(z-x)

• Korean Journal of Mathematics
• /
• v.17 no.1
• /
• pp.103-112
• /
• 2009

We show the existence of the solutions for the following nonlinear elliptic problem under the Dirichlet boundary condition. To show the existence of the solutions we use the variational formulation.

• Journal of applied mathematics & informatics
• /
• v.7 no.1
• /
• pp.175-181
• /
• 2000

The purpose of this to measure, with explicit constants as small as possible, a priori error bounds for approximation by picewise polynomials. These constants play an important role in the numerical verification method of solutions for obstacle problems by using finite element methods .

• Journal of applied mathematics & informatics
• /
• v.16 no.1_2
• /
• pp.279-287
• /
• 2004

In this paper, we establish relations between a solution of a vector continuous-time program and a solution of a vector variational-type inequality problem with functionals.

• Journal of applied mathematics & informatics
• /
• v.28 no.3_4
• /
• pp.877-882
• /
• 2010

In this paper, a third-order three-point boundary value problem on time scales is considered. We establish criteria for the existence of a solution and a positive solution by using the Leray-Schauder fixed point theorem. An example is also given to illustrate our results.

• Korean Journal of Mathematics
• /
• v.18 no.2
• /
• pp.105-118
• /
• 2010

The purpose of this paper is to consider an iterative method for an equilibrium problem and a family relatively nonexpansive mappings. Weak convergence theorems are established in uniformly smooth and uniformly convex Banach spaces.

• Journal for History of Mathematics
• /
• v.14 no.2
• /
• pp.93-100
• /
• 2001

The problem of vagueness has been investigated for a long time by philosophers and mathematicians. There are there approaches in mathematics to the problem, which are probability theory, fuzzy logic, and rough set theory. In this paper I introduce these theories and their meanings.

• The Pure and Applied Mathematics
• /
• v.13 no.3 s.33
• /
• pp.237-247
• /
• 2006

In this paper we solve the Hyers-Ulam stability problem for quadratic functional equations on restricted domains, and then obtain an asymptotic behavior of quadratic mappings on restricted domains.

• Journal of the Chungcheong Mathematical Society
• /
• v.35 no.1
• /
• pp.33-37
• /
• 2022

In this short note, we prove an open problem for the interval (-∞, ∞), related to a reverse trigonometric Masjed-Jamei inequality presented in [2] and establish a new inequality of a similar kind.