• Bulletin of the Korean Mathematical Society
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• v.27 no.2
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• pp.183-188
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• 1990

The notion of a Dirichlet set has been studied for several decades. Such sets are named in honour of Dirichlet's Theorem [4, pp.235] which, in modern terminology, simply says that every finite set in R is a dirichlet set. In this paper, we present a structure theorem which characterizes all D-sets on the real line. We also use our structure theorem to give a new proof of a known criterion for proving that a set fails to be a D-set.

• Journal of the Chungcheong Mathematical Society
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• v.27 no.4
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• pp.707-720
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• 2014

We get a theorem which shows the existence of at least three solutions for some elliptic system with Dirichlet boundary condition. We obtain this result by using the finite dimensional reduction method which reduces the infinite dimensional problem to the finite dimensional one. We also use the critical point theory on the reduced finite dimensioal subspace.