• 제목/요약/키워드: Subdivision

검색결과 604건 처리시간 0.02초

다차원 특징 공간에서의 효울적 패턴 분할 기법 (An Efficient Pattern Partitioning Method in Multi-dimensional Feature Space)

  • 김진일
    • 한국정보처리학회논문지
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    • 제5권3호
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    • pp.833-841
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    • 1998
  • 본 논문에서는 다차원 특징 공간에서 퍼지규칙을 자동으로 생성하기 위해 다차원 공간을 효과적으로 패턴 분할하는 방법을 제안한다. 제안된 방법은 패턴 공간의 순차적 재분할(sequential subdivision)에 기초하며, 생성된 패턴 부공간의 크기는 불규칙하다. 제안된 방법에서 최초의 n차원 패턴 공간은 패턴의 분포 특성을 고려하여 서로 다른 크기를 갖는 2개의 부공간으로 분할된다. 이 부공간중 재분할할 패턴 공간이 선택되고, 이 재분할은 중지 조건이 만족될 때까지 재귀적으로 반복된다. 본 제안의 결과는 인공위성 Landsat TM을 사용한 2,4,7번 밴드의 다중분광 이미지에 적용시켰으며, 만족할 만한 결과를 얻을 수 있었다.

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일본 여대생의 라이프스타일과 의류구매행동에 관한 연구 (A Study on the Japanese University Students' Clothing Buying Behavior according to Their Lifestyle)

  • 이옥희;김진경
    • 한국의류학회지
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    • 제29권2호
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    • pp.298-306
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    • 2005
  • The Main objective of this study was to investigate the relationship between lifestyle and clothing buying behavior of college female students in Japan. A questionnaire was developed to measure clothing urchasing motives, fashion information sources, evaluation criteria of clothing, store attribute and lifestyle, The questionnaire was administered to 131 female college students in Tokyo of Japan. the data was analyzed using percentage, frequency, mean, factor analysis, Cluster Analysis and ANOVA, Duncan Multiple Range test. The results of the study were as follows : 1. The female college students were classified into fourth subdivisions by the cluster analysis; rational group, economic group, progressive group, fashion-oriented group. 2. The clothing purchasing motives o consumers were significantly different according to lifestyle subdivision in social, personal. 3. In the case of fshion information sources, significant differences were found according to lifestyle subdivision in mass media information, information by marketer, information by consumer. 4. The evaluation criteria of clothing were significantly different depending on lifestyle subdivision in esthetic, quality and management, external criterion. 5. The store attribute were significantly different depending on lifestyle subdivision in convenience, service and atmosphere of store.

섬 관광객의 지리적 시장세분화에 관한 연구 (A Study on Geographical Market Segmentation of Island Tourists)

  • 이진희
    • 수산경영론집
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    • 제49권4호
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    • pp.53-68
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    • 2018
  • The industrial structure of Chuja Island is mainly occupied by fisheries. Since the fisheries resources have been depleted and the marine environment has been changed, the fishery industry has been hard to survive. It is the time when residents are looking for a breakthrough in the tourism industry. Market segmentation is a valuable tool in the establishment of marketing strategies. Segmentation of tourists by the same desire and motivation is an essential factor in identifying the characteristics of tourists. The research on market segmentation of tourism sector focuses mainly on demographic subdivision, psychological subdivision, and behavioral subdivision, so it is urgent to study geographical market segmentation. The purpose of this study is to present data that can be used to establish a marketing strategy for tourism promotion in Chuja Island by analyzing the tourism activities via subdivision market according to demographic characteristics, tourism behavior characteristics, and tourism motivation after grasping the geographical segment of tourists through empirical analysis. In this study, 285 valid samples were analyzed by frequency analysis, ${\chi}^2$ test, cluster analysis and ANOVA test.

격자 세분화 방법을 고려한 복사열전달 형상계수 계산 기법 연구 (STUDY ON VIEW FACTOR CALCULATION FOR RADIATIVE HEAT TRANSFER BY USING THE MESH SUBDIVISION METHOD)

  • 김동건;한국일;최준혁;이장준;김태국
    • 한국전산유체공학회지
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    • 제19권1호
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    • pp.1-6
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    • 2014
  • Since experiments on the actual operational status are said to be very impractical because of their economic and repeatability problems, it is difficult to understand the thermal profiles of aerospace or military equipments. Thus, the CFD codes with considering the radiation heat transfer are used to compensate the defect. In case, analyzing the radiation exchanges between the object surfaces are very important. Because the temperature and the IR signal distributions of the object surface are significantly affected by the radiative heat transfer. To achieve accurate thermal radiation exchange between surfaces, it is important to calculate the radiation view factor precisely. Finer subdivision of meshes can be used to increase the accuracy of radiation view factor, but if the mesh is subdivided infinitely, the time required for calculation increases significantly and thus decreasing the efficiency. If the subdivision is not sufficient, assurance of accuracy is not guaranteed. In this paper, optimal mesh subdivision method using the solid angle has been successfully tested and found to be useful in increasing the efficiency of calculating the shape factors.

디렉토리 분류체계의 표준구분 관련 항목 전개 (Deployment of Standard Subdivisions Topics in Directory Classification Scheme)

  • 김성원
    • 정보관리학회지
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    • 제25권3호
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    • pp.357-375
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    • 2008
  • 인터넷의 보급 및 이용 활성화에 따라 인터넷을 통한 정보의 검색 및 획득이 정보검색의 일차적인 행태가 되고 있다. 인터넷을 통한 정보검색의 보편화는 인터넷 정보검색 포털이 제공하는 검색서비스의 중요성을 증대시키고 있다. 포털에서 제공하는 정보검색 서비스의 효율화는 인터넷 정보검색 환경의 효율화로 직결될 수 있다. 이에 본 고에서는 인터넷 정보검색 포털에서 제공하고 있는 서비스 가운데 인터넷 정보자료를 선별하고 조직화하여 제공하고 있는 디렉토리 서비스의 분류체계에 대해 고찰하였다. 구체적인 연구주제로 전통적인 문헌분류법에서 여러 주제분야에 공통적으로 적용될 수 있는 형식, 접근법을 모아 구성한 표준구분(standard subdivision) 항목들을 디렉토리 분류체계에서 어떻게 전개하고 있는 지 현황을 분석해 보았다. 이러한 분석을 기반으로 전통적인 문헌분류법의 표준구분에 포함된 항목들을 디렉토리 서비스에서 전개하는 방안을 제시하였다.

곡면간의 교차곡선 계산을 위한 개선된 Tracing 알고리즘 (An Improved Tracing algorithm for surface/surface intersection)

  • 조두연;이규열;임중현
    • 한국CDE학회논문집
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    • 제4권3호
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    • pp.269-283
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    • 1999
  • Surface/surface intersection is a common and important problem in geometric modeling and CAD/CAM. Several methods have been used to approach this problem. All possible intersection curves can be obtained by using the subdivision algorithm, while it requires a great deal of memory and is somewhat inefficient. The tracing algorithm is much faster than the subdivision algorithm, and can find points on the intersection curve sequentially. But, the tracing algorithm has some problems in the intersection curves on surface boundaries. In this paper, an Improved tracing algorithm that includes some ideas such as a new trace-terminating condition for the intersection curves on surface boundaries, detecting closed intersections and extension for composite surfaces is suggested. This algorithm consists of three step: generating state points for curve tracing, tracing intersection curves and sorting pieces of the intersection curves. The results of this algorithm and comparisons to the 'DESIGNBASE' and 'ACIS' system are presented.

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다항식곡선으로부터 순차적 방법에 의한 점열의 생성 (A Tessellation of a Polynomial Curve by a Sequential Method)

  • 주상윤
    • 한국CDE학회논문집
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    • 제11권3호
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    • pp.205-210
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    • 2006
  • Curve tessellation, which generates a sequence of points from a curve, is very important for curves rendering on a computer screen and for NC machining. For the most case the sequence of discrete points is used rather than a continuous curve. This paper deals with a method of tessellation by calculating the maximal deviation of a curve. The maximal deviation condition is introduced to find the point with the maximal chordal deviation on a curve segment. In the previous research a curve tessellation was tried by the subdivision method, that is, a curve is subdivided until the maximal chordal deviation is less than the given tolerance. On the other hand, a curve tessellation by sequential method is tried in this paper, that is, points are generated successively by using the local property of a curve. The sequential method generates relatively much less points than the subdivision method. Besides, the sequential method can generate a sequence of points from a spatial curve by approximation to a planar curve. The proposed method can be applied for high-accuracy curve tessellation and NC tool-path generation.

A New Method for Reconstruction of Smooth Branching Surface from Contours

  • Jha, Kailash
    • International Journal of CAD/CAM
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    • 제12권1호
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    • pp.29-37
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    • 2012
  • A new algorithm has been developed to construct surface from the contours having branches and the final smooth surface is obtained by the reversible Catmull-Clark subdivision. In branching, a particular layer has more than one contour that correspond with at least one contour at the adjacent layer. In the next step, three-dimensional composite curve is constructed from contours of a layer having correspondence with at least one contour at the adjacent layer by inserting points between them and joining the contours. The points are inserted in such a way that the geometric center of the contours should merge at the center of the contours at the adjacent layer. This process is repeated for all layers having branching problems. Polyhedra are constructed in the next step with the help of composite curves and the contours at adjacent layer. The required smooth surface is obtained in the proposed work by providing the level of smoothness.

폴리곤모델의 국부적 홀 메움 및 유연화에 관한 연구 (A Study on Local Hole Filling and Smoothing of the Polygon Model)

  • 유동진
    • 한국정밀공학회지
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    • 제23권9호
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    • pp.190-199
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    • 2006
  • A new approach which combines implicit surface scheme and recursive subdivision method is suggested in order to fill the holes with complex shapes in the polygon model. In the method, a base surface is constructed by creating smooth implicit surface from the points selected in the neighborhood of holes. In order to assure C$^1$ continuity between the newly generated surface and the original polygon model, offset points of same number as the selected points are used as the augmented constraint conditions in the calculation of implicit surface. In this paper the well-known recursive subdivision method is used in order to generate the triangular net with good quality using the hole boundary curve and generated base implicit surface. An efficient anisotropic smoothing algorithm is introduced to eliminate the unwanted noise data and improve the quality of polygon model. The effectiveness and validity of the proposed method are demonstrated by performing numerical experiments for the various types of holes and polygon model.

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

  • 설주환;양성봉
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
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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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