• Title/Summary/Keyword: conformal

Search Result 770, Processing Time 0.021 seconds

Analysis of the Radiation Pattern of Conformal Array Transducers (곡면 배열 트랜스듀서의 방사 특성 해석)

  • Kim, Hoe-Yong;Roh, Yong-Rae
    • The Journal of the Acoustical Society of Korea
    • /
    • v.29 no.7
    • /
    • pp.431-438
    • /
    • 2010
  • The radiation pattern of conformal transducers installed on a curved surface is likely to be complicated depending on the array pattern on the curved surface. In this research, the acoustic sources constituting a conformal transducer are arrayed in equi-angle, equi-interval, and geodesic dome forms, and the radiation pattern function of each of the array geometries has been derived, and therewith the radiation pattern has been analyzed for each array geometry. Based on the analysis result, we have determined the equi-interval array geometry that provides the widest beam width with the lowest side lobe level among the three array geometries. Results of the present work are expected to be utilized to the design of conformal transducer structures.

ZERO SCALAR CURVATURE ON OPEN MANIFOLDS

  • Kim, Seong-Tag
    • Communications of the Korean Mathematical Society
    • /
    • v.13 no.3
    • /
    • pp.539-544
    • /
    • 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.

  • PDF

EMBEDDING OPEN RIEMANN SURFACES IN 4-DIMENSIONAL RIEMANNIAN MANIFOLDS

  • Ko, Seokku
    • Bulletin of the Korean Mathematical Society
    • /
    • v.53 no.1
    • /
    • pp.205-214
    • /
    • 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 ${\geq}3$.

THE PROPERTIES OF RIEMANNIAN FOLIATIONS ADMITTING TRANSVERSAL CONFORMAL FIELDS

  • Jung, Seoung Dal;Lee, Keum Ran
    • Bulletin of the Korean Mathematical Society
    • /
    • v.55 no.4
    • /
    • pp.1273-1283
    • /
    • 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.

Conformal Change in Einstein's *gλʋ-Unified Field Theory. -II, The Vector Sλ

  • CHUNG, KYUNG TAE
    • Journal of the Korean Mathematical Society
    • /
    • v.11 no.1
    • /
    • pp.29-31
    • /
    • 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.

  • PDF

A STUDY ON THE EFFECTIVE ALGORITHMS BASED ON THE WEGMANN'S METHOD

  • Song, Eun-Jee
    • Journal of applied mathematics & informatics
    • /
    • v.20 no.1_2
    • /
    • pp.595-602
    • /
    • 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.

SOME APPLICATIONS OF EXTREMAL LENGTH TO CONFORMAL IMBEDDINGS

  • Chung, Bo-Hyun
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.22 no.2
    • /
    • pp.211-216
    • /
    • 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.

  • PDF

Analysis on the practicality and manufacture by DMLS and NC Multiple machines (DMLS와 NC복합가공기의 실용성 검토)

  • Moon, Dae-Young
    • Design & Manufacturing
    • /
    • v.9 no.3
    • /
    • pp.34-40
    • /
    • 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.

  • PDF

Errors of the conformal mapping method in the analysis of electrodes (전극 해석에서 등각사상법의 오차 평가)

  • 한영진;김창민
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.32A no.8
    • /
    • pp.71-77
    • /
    • 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.

  • PDF

CONFORMAL FIELD THEORY OF DIPOLAR SLE(4) WITH MIXED BOUNDARY CONDITION

  • Kang, Nam-Gyu
    • Journal of the Korean Mathematical Society
    • /
    • v.50 no.4
    • /
    • pp.899-916
    • /
    • 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).