• 한국음향학회지
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• 제29권7호
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• pp.431-438
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• 2010

곡면에 지지된 음원의 경우 음원의 배열 방식에 따라 방사되는 음장이 매우 복잡한 특성을 가진다. 본 연구에서는 곡면 배열 트랜스듀서를 구성하는 음원을 등각, 등간격 그리고 geodesic dome 형태로 배열하여, 각각의 배열 방식에 따른 음향 방사 패턴 함수를 유도하고, 그에 따라 방사 패턴을 해석하였다. 해석 결과를 바탕으로 3가지 배열 방법 가운데 상대적으로 주엽의 빔 폭이 크고 부엽의 크기가 작은 경향을 보이는 등간격 배열을 곡면 배열 트랜스듀서의 구조로 선정하였다. 본 연구 결과는 곡면 배열 트랜스듀서의 구조 설계에 활용될 수 있을 것으로 기대된다.

• 대한수학회논문집
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• 제13권3호
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• pp.539-544
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• 1998

Let (M, g) be a noncompact complete Riemannian manifold of dimension n $\geq$ 3 with scalar curvature S, which is close to O. With conditions on a conformal invariant and scalar curvature of (M, g), we show that there exists a conformal metric (equation omitted), near g, whose scalar curvature (equation omitted) = 0 by gluing solutions of the corresponding partial differential equation on each bounded subsets $K_{i}$ with ∪$K_{i}$ = M.

• 대한수학회보
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• 제53권1호
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• pp.205-214
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• 2016

Any open Riemann surface has a conformal model in any orientable Riemannian manifold of dimension 4. Precisely, we will prove that, given any open Riemann surface, there is a conformally equivalent model in a prespecified orientable 4-dimensional Riemannian manifold. This result along with [5] now shows that an open Riemann surface admits conformal models in any Riemannian manifold of dimension ${\geq}3$.

• 대한수학회보
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• 제55권4호
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• pp.1273-1283
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• 2018

Let ($M,{\mathcal{F}}$) be a closed, oriented Riemannian manifold of a foliation ${\mathcal{F}}$ with a nonisometric transversal conformal field. Then ($M,{\mathcal{F}}$) is transversally isometric to the sphere under some transversal concircular curvature conditions.

• 대한수학회지
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• 제11권1호
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• pp.29-31
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• 1974

In the first paper of this series, [2], we investigated how the conformal change enforces the connections and gave the complete relations between connections in Einstein's $^*g^{{\lambda}{\nu}}$-unified field theory. In the current paper we wish to investigate how the vector def $$S_{{\lambda}{{\mu}}{{^\mu}}{=^{def}}S_{\lambda}$$ is transformed by the conformal change. This topics will be studied for all classes and all possible indices of inertia.

• Journal of applied mathematics & informatics
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• 제20권1_2호
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• pp.595-602
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• 2006

Determinations of conformal map from the unit disk onto a Jordan region are reduced to solve the Theodorsen equation which is an integral equation for the boundary correspondence function. Among numerical conformal maps the Wegmann's method is well known as a Newton efficient one for solving Theodorsen equation. However this method has not so wide class of convergence. We proposed as an improved method for convergence by applying a low frequency filter to the Wegmann's method. In this paper, we investigate error analysis and propose an automatic algorithm based on this analysis.

• 충청수학회지
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• 제22권2호
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• pp.211-216
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• 2009

Let G be a Denjoy domain and let G' a Denjoy proper subdomain of G and homeomorphic to G. We consider conformal re-imbeddings of G' into G. Let G and G' are N-connected. We know that if N = 2, there is a re-imbedding f of G' into G such that G - cl(f(G')) has an interior point. In this note, we obtain the following theorem. If $N{\geq}3$, G has a Denjoy proper subdomain G' such that, for any re-imbeddings f of G' into G, G - cl(f(G') has no interior point.

• Design & Manufacturing
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• 제9권3호
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• pp.34-40
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• 2015

In the study, Three-dimensional drawing parts for conformal cooling circuit cavity & core and their 3D Metal parts using DMLS(Direct MetalLaser Sintering) and NC integrated machining center were showned. For conformal cooling circuit cavity and core parts, I discussed its practicality to DMLS multiple machinins process introducing general manufacturing process and comparing with them.

• 전자공학회논문지A
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• 제32A권8호
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• pp.71-77
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• 1995

Evaluated are errors of the conformal mapping method in the analysis of a coplanar waveguides and asmmetric coplanar strips. The errors are mainly due to the negligence of fringe field effect after electrode structures are transformed to parallel electrodes. For the purpose of comparison, results of the conformal mapping(CM) method are compared with those of the successive over relaxation(SOR) method.

• 대한수학회지
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• 제50권4호
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• pp.899-916
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• 2013

We develop a version of dipolar conformal field theory in a simply connected domain with the Dirichlet-Neumann boundary condition and central charge one. We prove that all correlation functions of the fields in the OPE family of Gaussian free field with a certain boundary value are martingale-observables for dipolar SLE(4).