• 제목/요약/키워드: space partitioning

검색결과 175건 처리시간 0.03초

직선으로 둘러싸인 영역과 비평면적 표면 상에서의 회로 분할과 배치를 위한 그래프 매칭 알고리즘 (A Graph Matching Algorithm for Circuit Partitioning and Placement in Rectilinear Region and Nonplanar Surface)

  • 박인철;경종민
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
    • /
    • pp.529-532
    • /
    • 1988
  • This paper proposes a graph matching algorithm based on simulated annealing, which assures the globally optimal solution for circuit partitioning for the placement in the rectilinear region occurring as a result of the pre-placement of some macro cells, or onto the nonplanar surface in some military or space applications. The circuit graph ($G_{C}$) denoting the circuit topology is formed by a hierarchical bottom-up clustering of cells, while another graph called region graph ($G_{R}$) represents the geometry of a planar rectilinear region or a nonplanar surface for circuit placement. Finding the optimal many-to-one vertex mapping function from $G_{C}$ to $G_{R}$, such that the total mismatch cost between two graphs is minimal, is a combinatorial optimization problem which was solved in this work for various examples using simulated annealing.

  • PDF

A Sector-Labeling for generating the Hilbert Space-filling Curve and Its Intention

  • Slamet, Santosa;Naoi, Tohru
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2002년도 ITC-CSCC -1
    • /
    • pp.38-41
    • /
    • 2002
  • Many scientifc applications include manipulation of data points tying in a space. We describe a method, based on sector labeling to generate a space-filling curve for partitioning such given data points. Our method is straightforward and flexible, equipping a one-one correspondence between point-values on the curve and data points in space in more efficient than designated methods found in the literature. It is widely believed that the Hilbert curve achieves the desired properties on linear mappings due to the locality between data points. Therefore we focus on the Hilbert curve since, later on, we identify it as the most suitable for our application. We demonstrate on using our method for the data particles of an n-body simulation that based on Barnes-Hut algorithm.

  • PDF

Design and Performance of Space-Time Trellis Codes for Rapid Rayleigh Fading Channels

  • Zummo, Salam A.;Al-Semari, Saud A.
    • Journal of Communications and Networks
    • /
    • 제5권2호
    • /
    • pp.174-183
    • /
    • 2003
  • Space-Time (ST) codes are known to provide high transmission rates, diversity and coding gains. In this paper, a tight upper bound on the error probability of ST codes over rapid fading channels is presented. Moreover, ST codes suitable for rapid fading channels are presented. These codes are designed using the QPSK and 16-QAM signal constellations. The proposed codes are based on two different encoding schemes. The first scheme uses a single trellis encoder, whereas the second scheme uses the I-Q encoding technique. Code design is achieved via partitioning the signal space such that the design criteria are maximized. As a solution for the decoding problem of I-Q ST codes, the paper introduces a low-complexity decoding algorithm. Results show that the I-Q ST codes using the proposed decoding algorithm outperform singleencoder ST codes with equal complexity. The proposed codes are tested over fading channels with different interleaving conditions, where it is shown that the new codes are robust under such imperfect interleaving conditions.

ESTIMATION OF SOIL MOISTURE WITH AIRBORNE L-BAND MICROWAVE RADIOMETER

  • Chang, Tzu-Yin;Liou, Yuei-An
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
    • /
    • pp.26-28
    • /
    • 2008
  • Soil moisture plays an important role in the land-atmosphere energy balance because it governs the partitioning of energy through latent heat fluxes or evapotranspiration. From the numerous studies, it is evident that the L-band radiometer is a useful and effective tool to measure soil moisture. The objective of the study is to develop and to verify the soil moisture retrieval algorithms for the L-band radiometer system. Through the radiometer-observed brightness temperature, surface emissivity and reflectivity can be derived, and, hence, soil moisture. We collect field and L-band airborne radiometer data from washita92, SGP97 and SGP99 experiments to assist the development of the retrieval algorithms. Upon launching the satellite L-band radiometer such as ESA-sponsored SMOS (Soil Moisture and Ocean Salinity) mission, the developed algorithms may be used to study and monitor globe soil moisture change.

  • PDF

2차원 평면상에 4차원 가시성 정보의 표현을 통한 포괄적 가시성 전처리 (Conservative Visibility Preprocessing by Expressing 4-D visibility Information on 2-D Spaces)

  • 허준혁;원광연
    • 한국컴퓨터그래픽스학회논문지
    • /
    • 제5권2호
    • /
    • pp.9-23
    • /
    • 1999
  • 가시성 전처리는 렌더링을 위하여 실시간에 처리되어야 하는 다각형의 수를 줄여, 전체 랜더링 성능을 향상시키는 유용한 방법 중에 하나이다. 본 논문에서는 새롭고 효율적인 가시성 전처리 방법을 제안하였다. 제안된 방법에서는 가상환경 내에서 네비게이션 가능한 지역들이 사전에 직육면체 형태의 셀들로 분할되어 있다고 가정한다. 분할된 하나의 셀에서 보일 가능성이 있는 다각형을 구하기 위해서는 적어도 면-대-면 가시성을 해결해야 한다. 이는 4차원의 가시성 정보를 다루어야 함을 의미한다. 제안된 방법에서는 이러한 4차원이라는 고차원의 가시성 정보를 보다 효율적으로 처리하기 위해서, 포괄적 가시성의 특성을 이용하여 4차원의 정보를 2차원의 평면들에 나타내고 이를 개념적으로 2진공간분할(Binary Space Partitioning) 트리와 유사한 3진트리로 표현하여 처리하였다. 제안된 방법은 건축물 내부환경뿐만 아니라, 도시환경과 같은 보다 일반적인 야외환경도 다룰 수 있으며, 여러 개의 다각형들이 협력적으로 가리는 다각형들도 제거할 수 있다. 제안된 방법은 O(nm)의 계산 시간과 O(n+m)의 공간을 요구한다. 적당한 m을 선택함으로써 사용자는 전처리시간과 계산결과사이에 적절한 선택을 할 수 있다.

  • PDF

실내공간에 있어 자연광에 의한 시지각적 현상에 관한 연구 (A Study on the Visual Phenomenon of Natural Light in Interior Space)

  • 김주연
    • 한국실내디자인학회논문집
    • /
    • 제13호
    • /
    • pp.130-138
    • /
    • 1997
  • This study is to present the visual phenomenon of natural light in the interior space. The continuously changing natural light define the visual phenomenon of the architectural space. First, the objective of this study was finding the importance of the visual phenomena which were generated from correlating natural right with the interior space. And the second was to categorize the factors of the visual phenomenon which can be useful factors for modern interior design practice. As a result of this study, two visual phenomena were classified. First; territorial phenomenon: dividing, partitioning, and sectioning by natural light, Second; phenomena by the inflow methods of natural light; a) by direct inflow; transparency, expansion, and floating, b) by filtering fixtures; the architectural structure, color, and the transluscent material, c) by dramatic spacial present of natural light, d) by the sense of direction of naturel light; continuity, and transformatiov. Found and classified each factor is not presented by itself, rather compounded forms. Because of the limited analysis of modern buildings, these found visual factors can not represent all phenomena. But if we practice these finding factors to design present interior space, it is sure of being very valuable factors to re-introduce the overlooked natural light into interior space.

  • PDF

최소평균자승에러 알고리듬을 이용한 non-parametric 검파기 설계 (Design of Non-Parametric Detectors with MMSE)

  • 공형윤
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 추계종합학술대회 논문집
    • /
    • pp.171-174
    • /
    • 1998
  • A class of non-parametric detectors based on quantized m-dimensional noise sample space is introduced. Due to assuming the nongaussian noise as a channel model, it is not easy to design the detector through estimating the unknown functional form of noise; instead equiprobably partitioning m-dimensional noise into a finite number of regions, using a VQ and quantiles obtained by RMSA algorithm is used in this paper to design detectors. To show the comparison of performance between single sample detector and system suggested here, Monte-Carlo simulations were used. The effect of signal pulse shape on the receiver performance is analyzed too.

  • PDF

온도 제어 시스템을 위한 뉴로-퍼지 제어기의 설계 (The Design of an Adaptive Neuro-Fuzzy Controller for a Temperature Control System)

  • 곽근창;김성수;이상혁;유정웅
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2000년도 추계학술대회 학술발표 논문집
    • /
    • pp.493-496
    • /
    • 2000
  • In this paper, an adaptive neuro-fuzzy controller using the conditional fuzzy c-means(CFCM) methods is proposed. Usually, the number of fuzzy rules exponentially increases by applying the grid partitioning of the input space, in conventional adaptive neuro-fuzzy inference system(ANFIS) approaches. In order to solve this problem, CFCM method is adopted to render the clusters which represent the given input and output data. Finally, we applied the proposed method to the water path temperature control system and obtained a better performance than previous works.

  • PDF

군집로봇의 협조탐색을 이용한 공간분할기법 (The cooperate navigation for swarm robot using space partitioning technique)

  • 방문섭;김종선;주영훈;박진배
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2011년도 제42회 하계학술대회
    • /
    • pp.1892-1893
    • /
    • 2011
  • 본 논문에서는 Centroidal Voronoi Tessellation을 이용하여 군집로봇의 협조탐색을 위한 공간분할기법을 제안한다. 탐색공간은 Centroidal Voronoi Tessellation을 이용하여 분할한다. 전역 경로 계획 및 군집 로봇 간의 충돌 회피는 포텐셜 필드를 이용한다. 탐색공간에 밀도 함수를 사용하여 공간분할의 유동성을 부여한다. 마지막으로, 군집로봇의 협조탐색의 가능성을 시뮬레이션을 통하여 확인한다.

  • PDF

OSP Tree를 이용한 무한순차 입력 형상의 실시간 컬링에 관한 연구 (A Study on the Real Time Culling of Infinite Sets of Geometries Using OSP Tree)

  • 표종현;채영호
    • 한국CDE학회논문집
    • /
    • 제8권2호
    • /
    • pp.75-83
    • /
    • 2003
  • In this paper, OSP(Octal Space Partitioning) tree is proposed for the real time culling of infinite sets of geometries in interactive Virtual Environment applications. And MSVBSP(Modified Shadow Volume BSP) tree is suggested for the occlusion culling. Experimental results show that the OSP and MSVBSP tree are efficiently implemented in real time rendering of interactive geometries.