• 제목/요약/키워드: Topological Transformation

검색결과 40건 처리시간 0.028초

위상학적 공간 인식을 위한 효과적인 초음파 격자 지도 매칭 기법 개발 (Effective Sonar Grid map Matching for Topological Place Recognition)

  • 최진우;최민용;정완균
    • 로봇학회논문지
    • /
    • 제6권3호
    • /
    • pp.247-254
    • /
    • 2011
  • This paper presents a method of sonar grid map matching for topological place recognition. The proposed method provides an effective rotation invariant grid map matching method. A template grid map is firstly extracted for reliable grid map matching by filtering noisy data in local grid map. Using the template grid map, the rotation invariant grid map matching is performed by Ring Projection Transformation. The rotation invariant grid map matching selects candidate locations which are regarded as representative point for each node. Then, the topological place recognition is achieved by calculating matching probability based on the candidate location. The matching probability is acquired by using both rotation invariant grid map matching and the matching of distance and angle vectors. The proposed method can provide a successful matching even under rotation changes between grid maps. Moreover, the matching probability gives a reliable result for topological place recognition. The performance of the proposed method is verified by experimental results in a real home environment.

한글 문자의 인식을 위한 대수적 구조 (Algebraic Structure for the Recognition of Korean Characters)

  • 이주근;주훈
    • 대한전자공학회논문지
    • /
    • 제12권2호
    • /
    • pp.11-17
    • /
    • 1975
  • 이 논문은 한글문자의 자동인식을 위한 기초적인 연구로서 기본문자의 구조에 대해서 검토하였다. 기본문자를 구조, 선분구조 및 물자 graph의 node와의 연결곤계 들 구조를 세가지 측면에서 집합 및 군론에 의한 대수적인 분석을 하고 또 그들의 각 구조의 복잡성에 대한 계릉을 고찰하였다. 나아가서 10개의 모음은 한 요소의 Affine 변환에 의한 연속회전으로 이루어지는 회전변환군 속에서 다수의 동치관계가 존재한다는 것을 기술하므로써, 한글문자의 인식에 있어서는 topological 골격외에 기하적 성질이 특히 중요하다는 것을 아울러 지적 하였다. The paper examined the character structure as a basic study for the recognition of Korean characters. In view of concave structure, line structure and node relationship of character graph, the algebraic structure of the basic Korean characters is are analized. Also, the degree of complexities in their character structure is discussed and classififed. Futhermore, by describing the fact that some equivalence relations are existed between the 10 vowels of rotational transformation group by Affine transformation of one element into another, it could be pointed out that the geometrical properting in addition to the topological properties are very important for the recognition of Korean characters.

  • PDF

Three Dimensional Spatial Object Model

  • Lee, Sun-Jun;Kim, Sang-Ho;Lee, Seong-Ho;Chung, Jae-Du;Ryu, Keun-Ho
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.885-890
    • /
    • 2002
  • As Geographic Information Systems represents three-dimensional topological Information, the systems provide accurate and delicate services for user. In order to execute three-dimensional topological operations, a dimensional transformation and heterogeneous spatial models should be used. However, the existing systems that use the dimensional transformation and the heterogeneous models, are not only difficult to operate the spatial operators, but also happened to support non- interoperability. Therefore, in order to support the spatial operation as well as interoperability between dimensions, we propose three-dimensional spatial operators for the proposed models. We defined the three-dimensional spatial operators prior to designing the proposed model. We also implemented the operators of proposed model and evaluated the implemented model on the component environment. Finally, the proposed model is able to not only support interoperability among systems but also execute spatial queries efficiently on three-dimensional spatial objects.

  • PDF

다중축척 공간 데이터베이스의 축소연산자를 위한 위상관계 일관성 평가 (The Consistency Assessment of Topological Relationships For a Collapse Operator in Multi-Scale Spatial Databases)

  • 강혜경;이기준
    • 정보처리학회논문지D
    • /
    • 제12D권6호
    • /
    • pp.837-848
    • /
    • 2005
  • 다중축척 공간데이터베이스란 동일한 현실 공간을 여러 축척으로 저장한 것으로, 기존에 구축된 원시 공간 데이터베이스로부터 유도될 수 있다. 이 유도과정에서 원시 데이터베이스에 있던 기하 및 위상관계는 변형이 되고, 이 관계 변형은 유도된 데이터베이스의 무결성을 보장하지 못하는 원인이 되므로, 유도과정이 수행된 후에는 반드시 유도된 데이터베이스와 원시 데이터베이스의 관계 일관성을 조사해야한다. 이 논문에서는 원시 데이터베이스와 유도된 다중축척 데이터베이스간의 위상 관계 일관성을 평가하는 방법을 제시하겠다. 특히, 2차원 공간객체가 1차원으로 축소되었을 때 위상관계의 일관성을 평가하는 방법을 제한할 것이며, 이 평가 방법들의 구현에 대해서 기술하고, 사례를 이용하여 구현결과를 기술하겠다.

근대(近代) 도시화(都市化)에 따른 전라도(全羅道) 전통(傳統) 소도읍(小都邑)의 공간구조변화과정(空間構造變化過程) 연구(硏究) (A study on the Transformation Process of Traditional Small City Structure in Jeollabuk-Do)

  • 이경찬
    • 건축역사연구
    • /
    • 제11권3호
    • /
    • pp.21-34
    • /
    • 2002
  • This study is to analyse the transformation process of spatial structure of traditional small city structure in Jeollabuk-Do in the process of modern urbanization between 19th century and the year 2000. The small cities, IM-PI, YONG-AN, YEO-SAN, OK-GOO, GO-SAN, MU-JANG, GUM-MA, GO-BU, which have been local administrative center in CHO-SUN dynasty, have role of local administrative center of subdivision of country-myon, except OK-GOO. The method of this study is to investigate the transformation process of spatial structural elements of with the actual field surveys, the analysis of Gunhyun map made in 1872, land registration maps in 1910s and 2000, and various topological maps. The elements of analysis are the topological site and geographical situation conditions, the urbanized areas, the street systems, the function of streets, the focal points of urban land use, the land use systems, and the location of major facilities such as administration facilities, markets, bus terminals. The analytical point of view and the results are as follows. There is strong relationship between the transformation of internal matrix route system and the growth pattern of urbanized areas, Especially on the contrary to the matrix route with East-West direction which has the role of checking the growth of urbanized area, the South-North direction route acts as the leading line of the growth. The focal points structure of urban land use shows transformation process from the point of central space of administrative district in front of Nae-A, to the access point to administrative district or to the access point to housing and neighborhood commercial area. From the point of functional area structure and major facilities location, line-type commercial area is developed along the line of central axis route and access route to administrative district. Especially direction of the growth of commercial area is strongly connected with the interrelationship between the study area and its neighboring cities. Pattern of commercial district development is varied with the direction of matrix route. That is, commercial district, which shows one side development pattern along the East-West direction route, is developed on both sides of street along the South-North direction route.

  • PDF

The reidemeister numbers on transformation groups

  • Ahn, Soo-Youp;Chung, In-Jae
    • 대한수학회논문집
    • /
    • 제11권2호
    • /
    • pp.445-455
    • /
    • 1996
  • In this paper we study the Reidemeister number $R(f_G)$ for a self-map $f_G : (X, G) \to (X, G)$ of the transformation group (X,G), as an extenstion of the Reidemeister number R(f) for a self-map $f : X \to X$ of a topological space X.

  • PDF

GENERALIZED REIDEMEISTER NUMBER ON A TRANSFORMATION GROUP

  • Park, Ki Sung
    • Korean Journal of Mathematics
    • /
    • 제5권1호
    • /
    • pp.49-54
    • /
    • 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.

  • PDF

얇은 두께 솔리드의 효율적인 모델링을 위한 박판 옵셋 알고리즘 개발 (Sheet Offsetting Algorithms for Efficient Solid Modeling for Thin-Walled Parts)

  • 김현수;이상헌
    • 한국CDE학회논문집
    • /
    • 제5권3호
    • /
    • pp.242-254
    • /
    • 2000
  • This paper describes an efficient solid modeling method for thin-walled plastic or sheet metal parts, based on the non-manifold offsetting operations. Since the previous methods for modeling and converting a sheet into a solid have adopted the boundary representations for solid object as their topological framework, it is difficult to represent the exact adjacency relationship between topological entities of a sheet model and a mixture of wireframe and sheet models that can appear in the meantime of modeling procedure, and it is hard to implement topological operations for sheet modeling and transformation of a sheet into a solid. To solve these problems, we introduce a non-manifold B-rep and propose a sheet conversion method based on a non-manifold offset algorithm. Because the non-manifold offset aigorithm based on mathematical definitions results in an offset solid with tubular and spherical thickness-faces we modify it to generate the ruled or planar thickness-faces that are mostly shown in actual plastic or sheet metal parts. In addition, in order to accelerate the Boolean operations used the offset algorithm, we also develope an efficient face-face intersection algorithm using topological adjacency information.

  • PDF

A NOTE ON LIFTING TRANSFORMATION GROUPS

  • Cho, Sung Ki;Park, Choon Sung
    • Korean Journal of Mathematics
    • /
    • 제5권2호
    • /
    • pp.169-176
    • /
    • 1997
  • The purpose of this note is to compare two known results related to the lifting problem of an action of a topological group G on a G-space X to a coverring space of X.

  • PDF