• 제목/요약/키워드: topological structure

검색결과 292건 처리시간 0.026초

ARRANGEMENT OF ELEMENTS OF LOCALLY FINITE TOPOLOGICAL SPACES UP TO AN ALF-HOMEOMORPHISM

  • Han, Sang-Eon;Chun, Woo-Jik
    • 호남수학학술지
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    • 제33권4호
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    • pp.617-628
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    • 2011
  • In relation to the classification of finite topological spaces the paper [17] studied various properties of finite topological spaces. Indeed, the study of future internet system can be very related to that of locally finite topological spaces with some order structures such as preorder, partial order, pretopology, Alexandroff topological structure and so forth. The paper generalizes the results from [17] so that the paper can enlarge topological and homotopic properties suggested in the category of finite topological spaces into those in the category of locally finite topological spaces including ALF spaces.

Mobile Robot Exploration in Indoor Environment Using Topological Structure with Invisible Barcodes

  • Huh, Jin-Wook;Chung, Woong-Sik;Nam, Sang-Yep;Chung, Wan-Kyun
    • ETRI Journal
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    • 제29권2호
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    • pp.189-200
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    • 2007
  • This paper addresses the localization and navigation problem in the movement of service robots by using invisible two dimensional barcodes on the floor. Compared with other methods using natural or artificial landmarks, the proposed localization method has great advantages in cost and appearance since the location of the robot is perfectly known using the barcode information after mapping is finished. We also propose a navigation algorithm which uses a topological structure. For the topological information, we define nodes and edges which are suitable for indoor navigation, especially for large area having multiple rooms, many walls, and many static obstacles. The proposed algorithm also has the advantage that errors which occur in each node are mutually independent and can be compensated exactly after some navigation using barcodes. Simulation and experimental results were performed to verify the algorithm in the barcode environment, showing excellent performance results. After mapping, it is also possible to solve the kidnapped robot problem and to generate paths using topological information.

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3차원 위상구조 생성을 위한 노드 - 관계구조로의 CAD 자료 변환 (CAD Data Conversion to a Node-Relation Structure for 3D Sub-Unit Topological Representation)

  • 마크 스티븐스;최진무
    • 대한지리학회지
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    • 제41권2호
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    • pp.188-194
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    • 2006
  • 3차원 위상 자료는 응급상황 처리와 3차원 네트워크 분석 등의 3차원 공간분석에 필수적으로 요구된다. 이 연구에서는 현재까지의 3차원 위상 데이터 모델에 대해 살펴보고, 건물을 설계하기 위해 사용되는 2차원 CAD 도면 데이터로 부터 3차원 위상적 노드-관계 데이터를 추출하는 방법을 개발하였다. 이 방법은 중심축 변환과 위상적 노드-관계 알고리듬들을 이용한 두 단계로 이루어진다. 첫번째 단계는 중심축 변환 알고리듬을 이용하여 CAD 데이터에서 폴리곤이나 이중 선으로 표현되는 벽으로부터 그 중심선을 생성하여 벽의 골격을 추출하는 것이다. 두번째 단계는 추출된 벽의 골격 자료를 이용하여 방을 3차원 노드로하고 방들간의 연결을 관계로하는 위상적 노드-관계 구조를 생성하는 것이다. 따라서, 그러한 연결들은 노드들간의 이웃성 또는 연결성을 표현하게 된다. 결론적으로, 이러한 변환방법으로 미시적 수준의 개별 건물들의 내부구조를 표현하는 3차원 위상구조 데이터는 건물의 도면 작성에 자주 사용되는 CAD 데이터로 부터 쉽게 생성될 수 있을 것이다.

고른 구조의 역사 (The History of Uniform Structures)

  • 이승온;민병수
    • 한국수학사학회지
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    • 제17권3호
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    • pp.1-12
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    • 2004
  • 해석학에서는 위상 구조와 고른 구조를 거리 공간에서 다루었기 때문에 많은 혼동이 있었다. 거리 공간의 개념은 위상 구조로 일반화되었지만 '고르다'는 개념은 그 후에 앙드레 베이유에 의해서 고른 구조로 일반화되었다. 우리는 먼저 베이유의 삶과 그의 수학적 업적을 살피고 고른 구조의 역사와 발달에 대해서 알아볼 것이다.

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위상 변경 고유치 재해석 기법을 이용한 최적 구조물 동특성 변경 (Optimal Structural Dynamics Modification Using Eigen Reanalysis Technique of Technique of Topological Modifications)

  • 이준호;박영진;박윤식
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.77-81
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    • 2003
  • SDM (Structural Dynamics Modification) is a tool to improve dynamic characteristics of a structure, more specifically of a base structure, by adding or deleting auxiliary (modifying) structures. In this paper, the goal of the optimal SDM is set to maximize the natural frequency of a base plate structure by attaching serially-connected beam stiffeners. The design variables are chosen as positions of the attaching beam stiffeners, where the number of stiffeners is considered as a design space. The problem of non-matching interface nodes between the base plate and beam stiffeners is solved by using localized Lagrange multipliers, which act to glue the two structures with non-matching interface nodes. As fer the cases of non-matching interface nodes problem, the governing equation of motion of a structure can be considered from the viewpoint of a topological modification, which involves the change of the number of structural members and DOFs. Consequently, the eigenpairs of the beam-stiffened plate structure are obtained by using an eigen reanalysis technique of topological modifications. Evolution Strategies (ES), which is a probabilistic population-based optimization technique that mimics the principles from biological evolution in nature, is utilized as a mean for the optimization.

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TOPOLOGICAL R2-DIVISIBLE R3-SPACES

  • Im, Jang-Hwan
    • 대한수학회논문집
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    • 제17권4호
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    • pp.647-673
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    • 2002
  • There are many models to study topological $R^2$-planes. Unlike topological $R^2$-planes, it is difficult to find models to study topological R$^3$)-spaces. If an 4-dimensional affine plane intersects with R$^3$, we are able to get a geometrical structure on R$^3$ which is similar to R$^3$-space, and called $R^2$-divisible R$^3$-space. Such spatial geometric models is useful to study topological R$^3$-spaces. Hence, we introduce some classes of topological $R^2$-divisible R$^3$-spaces which are induced from 4-dimensional anne planes.

SEMI-ASYMPTOTIC NON-EXPANSIVE ACTIONS OF SEMI-TOPOLOGICAL SEMIGROUPS

  • Amini, Massoud;Medghalchi, Alireza;Naderi, Fouad
    • 대한수학회보
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    • 제53권1호
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    • pp.39-48
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    • 2016
  • In this paper we extend Takahashi's fixed point theorem on discrete semigroups to general semi-topological semigroups. Next we define the semi-asymptotic non-expansive action of semi-topological semi-groups to give a partial affirmative answer to an open problem raised by A.T-M. Lau.

PRETOPOLOGICAL CONVERGENCE QUOTIENT MAPS

  • Park, Sang-Ho
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제3권1호
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    • pp.33-40
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    • 1996
  • A convergence structure defined by Kent [4] is a correspondence between the filters on a given set X and the subsets of X which specifies which filters converge to points of X. This concept is defined to include types of convergence which are more general than that defined by specifying a topology on X. Thus, a convergence structure may be regarded as a generalization of a topology. With a given convergence structure q on a set X, Kent [4] introduced associated convergence structures which are called a topological modification and a pretopological modification. (omitted)

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위상학적 하중 재분배 방법을 이용한 부정정 트러스 구조 해석 (Indeterminate Truss Structure Analysis using Topological Load Redistribution Method)

  • 최원;김한중
    • 한국농공학회논문집
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    • 제57권6호
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    • pp.59-68
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    • 2015
  • Traditional structure analysis method is based on numerical matrix analysis to use the geometries consisting of the structure. The characteristics require a lot of computer memories and computational time. To avoid these weaknesses, new approach to analyze truss structure was suggested by adopting topological load redistribution method. The axial forces to be not structurely analyzed yet against outside loads were redistributed by using nodal equation of equilibrium randomly at each node without constructing global matrix. However, this method could not calculate the axial forces if structure is statically indeterminate due to degree of many indeterminacies. Therefore, to apply the method suggested in this research, all redundancies of truss structure were replaced by unit loads. Each unit load could make the deformation of a whole structure, and a superposition method was finally adopted to solve the simultaneous equations. The axial forces and deflections agreed with the result of commercial software within the relative error of 1 %, whereas in the case that the axial forces are relatively very smaller than others, the relative errors were increased to 2 %. However, as the values were small enough not to be considered, it was practically useful as a structural analysis model. This model will be used for structural analysis of truss type of large structure such as agricultural farming facility.

CLASSIFICATION OF SPACES IN TERMS OF BOTH A DIGITIZATION AND A MARCUS WYSE TOPOLOGICAL STRUCTURE

  • Han, Sang-Eon;Chun, Woo-Jik
    • 호남수학학술지
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    • 제33권4호
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    • pp.575-589
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    • 2011
  • In order to examine the possibility of some topological structures into the fields of network science, telecommunications related to the future internet and a digitization, the paper studies the Marcus Wyse topological structure. Further, this paper develops the notions of lattice based Marcus Wyse continuity and lattice based Marcus Wyse homeomorphism which can be used for studying spaces $X{\subset}R^2$ in the Marcus Wyse topological approach. By using these two notions, we can study and classify lattice based simple closed Marcus Wyse curves.