• Title/Summary/Keyword: space extension

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Computing Rotational Swept Volumes of Polyhedral Objects (다면체의 회전 스웹터 볼륨 계산 방법)

  • 백낙훈;신성용
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.2
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    • pp.162-171
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    • 1999
  • Plane sweep plays an important role in computational geometry. This paper shows that an extension of topological plane sweep to three-dimensional space can calculate the volume swept by rotating a solid polyhedral object about a fixed axis. Analyzing the characteristics of rotational swept volumes, we present an incremental algorithm based on the three-dimensional topological sweep technique. Our solution shows the time bound of O(n²·2?+T?), where n is the number of vertices in the original object and T? is time for handling face cycles. Here, α(n) is the inverse of Ackermann's function.

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A Study on the Development for the Real Estate Appraisal Information System (부동산 감정평가정보체계 구축을 위한 기초적 연구)

  • 김한수
    • Journal of the Korean housing association
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    • v.14 no.5
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    • pp.153-161
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    • 2003
  • As development of Information Technology and Internet are available, many industries are creating a lot of values through extension from physical space to virtual reality. However, use of Information Technology and Internet in real estate appraisal is unprepared. As a result, There is necessity of appraisal information system development based on GIS and Internet for pratical use of Information Technology. Therefore, in this study, presented development model which present a basic design of appraisal information system to fulfill information request in appraisal and use GIS and Internet.

AN EXTENSION OF GOTTLIEB GROUPS

  • Lee, Kee-Young;Woo, Moo-Ha
    • Journal of the Korean Mathematical Society
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    • v.34 no.3
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    • pp.653-659
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    • 1997
  • In this paper, we extend the Gottlieb groups of a space to the Gottlieb groups of a map and show some properties of those groups. Especially, We show the 2nd Gottlieb group of a map is contained in the center of the homotopy group of the map and show $G_n(F) = \pi_n(f)$ for an H-map f between H-spaces. We also show the Gottlieb subgroups $G_n(A), G_n(X) and G_n(f)$ make a sequence if the map $f : A \to X$ has a right homotopy inverse.

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Diffuse Large B-cell Lymphoma of the Sacral Nerve Root; Presenting as a Polyradiculoneuropathy

  • Oh, Sung-Han;Noh, Jae-Sub;Chung, Bong-Sub;Paik, So-Ya
    • Journal of Korean Neurosurgical Society
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    • v.37 no.1
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    • pp.70-72
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    • 2005
  • Primary spinal cord lymphomas are rare, and are either extra-/intradural masses with leptomeningeal infiltration or intramedullary in nature. The authors present a patient with a diffuse large B-cell lymphoma involving the sacral nerve root, extension to extradural space, and the cranial nerve.

SPLITTINGS FOR THE BRAID-PERMUTATION GROUP

  • Jeong, Chan-Seok;Song, Yong-Jin
    • Journal of the Korean Mathematical Society
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    • v.40 no.2
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    • pp.179-193
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    • 2003
  • The braid-permutation group is a group of welded braids which is the extension of Artin's braid groups by the symmetric groups. It is also described as a subgroup of the automorphism group of a free group. We also show that the plus-construction of the classifying space of the infinite braid-permutation group has the following two types of splittings BBP(equation omitted) B∑(equation omitted) $\times$ X, BBP(equation omitted) B $^{+}$$\times$ Y=S$^1$$\times$Y, where X, Y are some spaces.

MAYER-VIETORIS SEQUENCE IN COHOMOLOGY OF LIE ALGEBROIDS ON SIMPLICIAL COMPLEXES

  • Oliveira, Jose R.
    • Communications of the Korean Mathematical Society
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    • v.33 no.4
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    • pp.1357-1366
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    • 2018
  • It is shown that the Mayer-Vietoris sequence holds for the cohomology of complexes of Lie algebroids which are defined on simplicial complexes and satisfy the compatibility condition concerning restrictions to the faces of each simplex. The Mayer-Vietoris sequence will be obtained as a consequence of the extension lemma for piecewise smooth forms defined on complexes of Lie algebroids.

GENERALIZED REIDEMEISTER NUMBER ON A TRANSFORMATION GROUP

  • Park, Ki Sung
    • Korean Journal of Mathematics
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    • v.5 no.1
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    • pp.49-54
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    • 1997
  • In this paper we study the generalized Reidemeister number $R({\varphi},{\psi})$ for a self-map $({\varphi},{\psi}):(X,G){\rightarrow}(X,G)$ of a transformation group (X, G), as an extension of the Reidemeister number $R(f)$ for a self-map $f:X{\rightarrow}X$ of a topological space X.

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A NONHARMONIC FOURIER SERIES AND DYADIC SUBDIVISION SCHEMES

  • Rhee, Jung-Soo
    • East Asian mathematical journal
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    • v.26 no.1
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    • pp.105-113
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    • 2010
  • In the spectral analysis, Fourier coeffcients are very important to give informations for the original signal f on a finite domain, because they recover f. Also Fourier analysis has extension to wavelet analysis for the whole space R. Various kinds of reconstruction theorems are main subject to analyze signal function f in the field of wavelet analysis. In this paper, we will present a new reconstruction theorem of functions in $L^1(R)$ using a nonharmonic Fourier series. When we construct this series, we have used dyadic subdivision schemes.