• Title/Summary/Keyword: Regular Subdivision

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A Study on the Grid Land Subdivision of Ancient Local City in Korea (고대 한국 지방도시 격자형 토지구획의 형태특성에 관한 연구)

  • Lee, Kyung-Chan
    • Journal of architectural history
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    • v.11 no.4 s.32
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    • pp.45-69
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    • 2002
  • This study aims to find out the genetic characteristics of gridded subdivision area which has its origin from ancient local administrative city-Sangju, Jeonju, Namwon, Kwangju, Chungju. The spatial structure, based on the inter-relationship among gridded subdivision area, city wall, and topographic condition, and the morphological characteristics of gridded subdivision area are analyzed. The points of analysis on morphological characteristics of gridded subdivision area consist of the size of unit block, the organization system of unit block, the orientation of subdivision line. As a result of the analysis, three main characteristics are found. Firstly there can be found no same land subdivision rule among study areas. Secondly, the morphological features of study area were the products of cumulative process of different subdivision areas which were developed in different periods. Thirdly, the original regular gridded land subdivision seems to have been carried out in the object of a farm-land cultivation around 7th century. And there was a change of land-use from farm land to urban land-use during the later 7th century and 8th century.

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Normal Meshes for Multiresolution Analysis on Irregular Meshes with a Boundary (다중해상도해석을 위한 Boundary를 가지는 비정규 메쉬의 Normal 메쉬화 방법)

  • 강성찬;이규열;김태완
    • Korean Journal of Computational Design and Engineering
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    • v.6 no.3
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    • pp.184-192
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    • 2001
  • In this paper we present a remeshing algorithm for irregular meshes with boundaries. The irregular meshes are approximated by regular meshes where the topological regularity is essential for the multiresolutional analysis of the given meshes. Normal meshes are utilized to reduce the necessary data size at each resolution level of the regularized meshes. The normal mesh uses one scalar value, i.e., normal offset value which is based on the regular rule of a uniform subdivision, while other remeshing schemes use one 3D vector at each vertex. Since the normal offset cannot be properly used for the boundaries of meshes, we use a combined subdivision scheme which resolves a problem of the proposed normal offset method at the boundaries. Finally, we show an example to see the effectiveness of the proposed scheme to reduce the data size of a mesh model.

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Forward Differencing for Rendering Catmull-Clark Subdivision Surfaces (포워드 디퍼렌싱을 이용한 Catmull-Clark 서브디비전 서피스 렌더링)

  • 설주환;양성봉
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10d
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    • pp.439-441
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    • 2002
  • 본 논문은 Catmull-Clark 서브디비전 서피스(subdivision surfaces)를 포워드 디퍼렌싱(forward differencing)을 이용하여 효율적으로 evaluation 해서 렌더링하는 알고리즘을 제안하고 있다. 포워드 디퍼렌싱은 순수한 다항식만을 evaluation 할 수 있다. 그러나 Catmull-Clark 서브디비전 서피스는 순수한 다항식이 아니다. 그러므로, Catmull-Clark 서피스를 정규 패치들(regular patches)로 분리하고, 그 패치들에 대한 다항식을 만들고, 포워드 디퍼렌싱을 사용해서 evaluation 하면 된다. 본 알고리즘의 장점은 전통적인 리커시브(recursive) 서브디비전 기법에 비해 메모리의 요구가 적다. 즉, [1]과 마찬가지로 서브디비전 깊이(subdivision depth)에 독립적으로 항상 상수(constant) 메모리 양 만큼만 요구된다.

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ON TROPICAL QUADRIC SURFACES

  • KIM, YONGGU
    • Honam Mathematical Journal
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    • v.28 no.1
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    • pp.83-111
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    • 2006
  • After introducing Tropical Algebraic Varieties, we give a polyhedral description of tropical hypersurfaces. Using TOPCOM and GAP, we show that there exist 59 types of two dimensional tropical quadric surfaces. We also show a criterion for a quadric hypersurface to be non-degenerate in terms of a tropical rank.

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Development of Delaunay Triangulation Algorithm Using Oct-subdivision in Three Dimensions (3차원 8분할 Delaunay 삼각화 알고리즘 개발)

  • Park S.H.;Lee S.S.
    • Korean Journal of Computational Design and Engineering
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    • v.10 no.3
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    • pp.168-178
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    • 2005
  • The Delaunay triangular net is primarily characterized by a balance of the whole by improving divided triangular patches into a regular triangle, which closely resembles an equiangular triangle. A triangular net occurring in certain, point-clustered, data is unique and can always create the same triangular net. Due to such unique characteristics, Delaunay triangulation is used in various fields., such as shape reconstruction, solid modeling and volume rendering. There are many algorithms available for Delaunay triangulation but, efficient sequential algorithms are rare. When these grids involve a set of points whose distribution are not well proportioned, the execution speed becomes slower than in a well-proportioned grid. In order to make up for this weakness, the ids are divided into sub-grids when the sets are integrated inside the grid. A method for finding a mate in an incremental construction algorithm is to first search the area with a higher possibility of forming a regular triangular net, while the existing method is to find a set of points inside the grid that includes the circumscribed sphere, increasing the radius of the circumscribed sphere to a certain extent. Therefore, due to its more efficient searching performance, it takes a shorer time to form a triangular net than general incremental algorithms.

A STUDY OF SUBDIVISION METHOD TO THREE AND FIVE SIDED FACES BASED ON REGULAR POLYGON

  • Muraki, Yuta;Konno, Kouichi;Tokuyama, Yoshimasa
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.551-556
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    • 2009
  • 3-D CAD (Computer Aided Design) system is an indispensable tool for manufacturing. A lot of engineers have studied for the methods to generate a curved surface on an N-sided shape, which is the basic technology of 3-D CAD systems. This surface generation, however, has three problems on the case of long and narrow shapes: the resultant surface is distorted, the surface is not continuous to adjacent surfaces, or additional user inputs are required to generate the surface. Conventional methods have not yet solved these problems at the same time. In this paper, we propose the method to generate internal curves that divide a long and narrow shape into regular N-sided sections so as to divide the shape into an N-sided section and four-sided ones. Our method controls the shape of internal curves by dividing an N-sided long and narrow shape into an N-sided section and four-sided ones, and solves distortion of the generated curved surface. In addition, each of the generated sections is interpolated with G1-continuous surfaces. This process does not require any user's further input. Therefore, the three problems mentioned above will be solved at the same time.

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Establishment on Management Plan of Environmental Noise with Noise Map (소음지도를 활용한 환경소음 관리계획 수립)

  • Sun, Hyosung
    • Journal of Environmental Impact Assessment
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    • v.20 no.2
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    • pp.123-131
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    • 2011
  • The objective of this study is to prepare the effective management plan of environmental noise with a noise map, and the guideline on the management plan of environmental noise was suggested through the review of existing application examples. The management plan of environmental noise with a noise map includes the practical contents in the stages of subdivision of management areas, establishment of reduction measures, opinion collection, post investigation, and reformulation of management plan. First, the classification of management regions is performed considering the excess degree of noise standard and the facility type in the phase of subdivision of management areas. Second, the optimal management plan is established through the investigation of regional characteristics and various noise reduction measures in the phase of establishment of reduction measures, which includes the examination of noise reduction effects with a noise map and the budget planning with the costing of noise reduction measures. Third, the opinion survey with a local resident and a expert is carried out in order to prove the validity of the management plan in the phase of opinion collection, and the management plan is modified with gathered opinions. Fourth, the post examination plan with noise measurement is performed in order to verify the real effect of noise reduction measures according to the management plan in the phase of post investigation. Finally, the amendment of the management plan as well as the improvement of a noise map is carried out at a regular cycle in the phase of reformulation of management plan.

Determinants of Employment of Regular Workers by Industrial Type: Focused on Outsourcing (산업유형별 상용직 고용 결정요인 - 외주(Outsourcing)를 중심으로)

  • Moon, Young-man;Kim, Jang-ho
    • Korean Journal of Labor Studies
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    • v.24 no.2
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    • pp.293-319
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    • 2018
  • This study analyzed the determinants of employment for the regular workers in the industrial type, and the results are as follows. First, 73.2% of companies use outsourcing as of 2015, and manufacturing (83.7%) is 20% p higher than non-manufacturing (63.7%). Over the past 10 years, the rate of outsourcing increased by 88.7% in manufacturing and 44.2% in non-manufacturing. Second, as a result of estimating the determinants of employment for regular workers, the variables of labor income distribution, operating profit, sales, R & D expenditure, foreign capital ratio significantly increase the employment of regular workers, while outsourcing, capital intensity, Were estimated to significantly reduce employment. Third, as a result of subdivision of industrial type and estimation of the effect of outsourcing on employment, it decreased employment of regular workers in all types. The size of influence was the biggest decrease in 'basic material type' in manufacturing industry and 'distribution service type' in non - manufacturing industry.

Direct Reconstruction of Displaced Subdivision Mesh from Unorganized 3D Points (연결정보가 없는 3차원 점으로부터 차이분할메쉬 직접 복원)

  • Jung, Won-Ki;Kim, Chang-Heon
    • Journal of KIISE:Computer Systems and Theory
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    • v.29 no.6
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    • pp.307-317
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    • 2002
  • In this paper we propose a new mesh reconstruction scheme that produces a displaced subdivision surface directly from unorganized points. The displaced subdivision surface is a new mesh representation that defines a detailed mesh with a displacement map over a smooth domain surface, but original displaced subdivision surface algorithm needs an explicit polygonal mesh since it is not a mesh reconstruction algorithm but a mesh conversion (remeshing) algorithm. The main idea of our approach is that we sample surface detail from unorganized points without any topological information. For this, we predict a virtual triangular face from unorganized points for each sampling ray from a parameteric domain surface. Direct displaced subdivision surface reconstruction from unorganized points has much importance since the output of this algorithm has several important properties: It has compact mesh representation since most vertices can be represented by only a scalar value. Underlying structure of it is piecewise regular so it ran be easily transformed into a multiresolution mesh. Smoothness after mesh deformation is automatically preserved. We avoid time-consuming global energy optimization by employing the input data dependant mesh smoothing, so we can get a good quality displaced subdivision surface quickly.

Chemotaxonomic and Phylogenetic Study on the Oligotrophic Bacteria Isolated from Forest Soil

  • Whang, Kyung-Sook
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2000.04a
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    • pp.150-156
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    • 2000
  • Oligotrophic bacteria isolated from forest soil showed a specific community consisting of various taxonomic groups compared with those in other soil or aquatic habitats. Based on the cell shape, the isolates were divided into four groups: regular rod, curved/spiral rod, irregular rod, and prosthecate bacteria. The cellular fatty acids 60 oligotrophic isolates were analyzed. The 30 fatty acids which were identified or characterized are classified. At the dendrogram based on cellular fatty acid composition, four clusters(I-IV) were separated at a euclidian distance of about 50. Cluster 3 and 4-a strains were containing Q-8, these strains are accommodated in the Proteobacteria gamma and beta subdivision. The chemotaxonomic profiles of the cluster 4-a strains showed good agreement with those of the genus Burkholderia. Cluster 3 was characterized by the presence of branched-chain fatty acids, iso-C15:0, iso-C17:1, and iso-C17:0 as the major components. These chemotaxonomy suggested the close relationship of the isolates with Xathomonas/Sterotrophomonas group. Based on the 16S rDNA sequence analysis, the two representative strains(MH256 and MA828) of cluster 3 showed the close relation to genera, Xathomonas/Sterotrophomonas, but were not included in these genera. These strains were even further away from core Xanthomonas, and clearly were seen to branch outside the cluster formed by the Sterotrophomonas maltophilia. MH256 and MA828 16S rDNA sequence was different enough to put new genus on a separate branch. The isolates with Q-10 were also studied. They are corresponded to the two large groups in Proteobacteria alpha subdivision. One was incorporated in the genus Bradyrhizobium cluster, which also includes Agromonas, a genus for oligotrophic bacteria. The strains of the other group showed high similarity to the genus Agrobacterium.

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