• Title/Summary/Keyword: Space Merging

검색결과 140건 처리시간 0.026초

Nitrogen self-enrichment in the starburst galaxies under the metal poor environments

  • Chung, Ji-Won;Sung, Eon-Chang;Rey, Soo-Chang;Kyeong, Jae-mann
    • 천문학회보
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    • 제35권2호
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    • pp.29.2-29.2
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    • 2010
  • We present elemental abundances of 412 blue compact dwarf galaxies (BCDs) at z=0.2~0.5 using the Sloan Digital Sky Survey (SDSS) DR7. The gas-phase nitrogen to oxygen abundance ratios (N/O) of sample galaxies increase as the oxygen to hydrogen abundance ratios (O/H) decrease. This indicates that the nitrogen is more enriched than the oxygen. We found that there is a noticeable distinction between the merger candidates and the isolated galaxies. Merging candidates show more enrichment of nitrogen abundance compared to isolated galaxies. On the other hand, neon and oxygen abundances for merging candidates are slightly lower than the isolated systems. We discuss the main cause of these trends with internal mixing and mass loss by fast rotation of young massive stars. We also discuss the environmental effect to the relation between specific star formation rate and galaxy mass.

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Merging Two Regional Geoid Estimates by Using Optimal Variance Components of Type repro-BIQUUE: An Algorithmic Approach

  • SCHAFFRIN Burkhard;MAUTZ Rainer
    • Korean Journal of Geomatics
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    • 제5권1호
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    • pp.1-6
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    • 2005
  • When merging various datasets the perennial problem of relative weighting arises. In case of two datasets an iterative algorithm has been developed recently that allows the rigorous determination of optimal variance components of type repro-BIQUUE even for large amounts of data, along with the estimation of the joint parameters. Here we shall present this new algorithm, and show its versatility in an example that will entail the merging of two regional geoid estimates (derived from EGM 96 and CHAMP) in terms of certain series expansions which have been proven previously to belong to the most efficient ones (e.g., wavelets, Hardy's multi-quadrics, etc.). Future attempts will be devoted to the sequential merging of altimeter and tide gauge data.

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Enhanced Locality Sensitive Clustering in High Dimensional Space

  • Chen, Gang;Gao, Hao-Lin;Li, Bi-Cheng;Hu, Guo-En
    • Transactions on Electrical and Electronic Materials
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    • 제15권3호
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    • pp.125-129
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    • 2014
  • A dataset can be clustered by merging the bucket indices that come from the random projection of locality sensitive hashing functions. It should be noted that for this to work the merging interval must be calculated first. To improve the feasibility of large scale data clustering in high dimensional space we propose an enhanced Locality Sensitive Hashing Clustering Method. Firstly, multiple hashing functions are generated. Secondly, data points are projected to bucket indices. Thirdly, bucket indices are clustered to get class labels. Experimental results showed that on synthetic datasets this method achieves high accuracy at much improved cluster speeds. These attributes make it well suited to clustering data in high dimensional space.

CUT TREE의 재구축 (RECONSTRUCTION OF THE CUT TREE)

  • 김채복
    • 대한산업공학회지
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    • 제19권3호
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    • pp.51-57
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    • 1993
  • This paper develops 0($n^3$) algorithm to construct a cut-tree generated by Gomory-Hu algorithm. The algorithm only requires node sets defined by the minimal cut in each of the (n-1) maximal flow determinations. Merging computerized facility layout procedure that uses cut-tree concept to generate design skeletons with our algorithm requires less storage space than merging it with Gomory-Hu algorithm. Also, the cut-tree can easily be modified when the (n-1) minimal cut-sets are updated due to changes on arc capacities.

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Mean Shift와 영역병합을 이용한 칼라 영상 분할 (A Color Image Segmentation Using Mean Shift and Region merging method)

  • 곽내정;권동진;김영길
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2006년도 춘계 종합학술대회 논문집
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    • pp.401-404
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    • 2006
  • mean shift 방법은 공간적 요소와 특징 요소를 결합하여 칼라 영상을 분할하는데 좋은 효율을 보인다. 그러나 입력되는 매개변수에 따라 분할된 결과가 달라지며 매개변수의 값이 작을 경우 많은 영역으로 분할되는 단점이 있다. 본 논문은 이러한 단점을 개선하여 mean shift로 분할된 영상이 과도하게 분할되었을 경우 영역병합 방법을 이용하여 유사영역을 병합 하는 방법을 제안한다. 제안방법은 과분할된 영상을 HSI 공간으로 변환하여 색상 정보를 이용하여 유사영역으로 병합하며 이때 경계영역을 보존하기 위해 병합 제한자를 이용하여 병합유무를 결정한다. 그 후 RGB 컬러 공간을 이용하여 HSI 컬러 공간에서 병합되지 않은 영역들을 병합하였다. 실험 결과는 다양한 영상에 대해 주요 영역들의 분할 결과에서 우수한 성능을 보여준다.

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Mean Shift 알고리즘과 영역 병합 방법을 이용한 경계선 보존 컬러 영상 분할 (An Edge Preserving Color Image Segmentation Using Mean Shift Algorithm and Region Merging Method)

  • 곽내정;권동진;김영길
    • 한국콘텐츠학회논문지
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    • 제6권9호
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    • pp.19-27
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    • 2006
  • Mean shift 방법은 중심 모드를 찾기 위한 비모수적 통계 방법으로 컬러 영상을 분할하는데 효율적이다. 그러나 입력되는 윈도우 크기에 따라 분할된 결과가 달라지며 윈도우의 크기 값이 작을 경우 많은 영역으로 분할되는 단점이 있다. 본 논문은 이러한 단점을 개선하여 mean shift 알고리즘에 의한 분할 영상이 과도하게 분할되었을 경우 영역 병합 방법을 이용하여 유사 영역을 병합하는 방법을 제안한다. 제안 방법은 과분할된 영상을 HSI 컬러 공간으로 변환하여 색상 정보를 이용하여 유사 영역으로 병합하며 이때 경계 영역을 보존하기 위해 영역 병합 제한자를 이용하여 병합 유무를 결정한다. 그 후 RGB 컬러 공간을 이용하여 HSI 컬러 공간에서 병합되지 않은 영역들을 병합하였다. 실험 결과는 다양한 영상에 대해 주요 영역들의 분할 결과에서 우수한 성능을 보여준다.

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RP 코드 합성을 기반으로 한 세 방향 영상에서의 삼차원 모델의 복원 (3-D Model Reconstruction from Three Orthogonal Views Based on Merging Technique of RP Codes)

  • 박순용;진성일
    • 전자공학회논문지B
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    • 제31B권4호
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    • pp.106-114
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    • 1994
  • A new merging technique is adopted for combining rectangular parallelepipes produced by 2-D rectangular code into more intuitive 30D volume elements. Rectangular parallelepiped codes (RP codes) can be used in volume-based representation of a three-dimensional object. We proposed more regularity-conserving 2-D rectangular coding scheme to merge rectangular cells represented by RP codes in three-dimensional space. After being constructed from modified 2-D rectangular code, 3-D RP codes are merged in the two orthogonal directions using new merging algorithm. The shape of merged 3-D object reconstructed by proposed algorithm is shown to be much closer to the original object shape than that of conventional RP codes. The storage requirement of merged object can be also reduced.

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