The Experts below are selected from a list of 24432 Experts worldwide ranked by ideXlab platform
I Puerari - One of the best experts on this subject based on the ideXlab platform.
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
The Astronomical Journal, 2005Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BV RI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, � ≈ 0.1 −0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ∼ 2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A − S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective. Subject headings: Galaxies: spiral – Galaxies: structure – Galaxies: photometry – Galaxies: interactions – Galaxies: fundamental parameters– Galaxies: morphology – Galaxies: general
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
arXiv: Astrophysics, 2004Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BVRI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, t ~ 0.1 - 0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ~2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A-S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective.
H M Hernandeztoledo - One of the best experts on this subject based on the ideXlab platform.
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
The Astronomical Journal, 2005Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BV RI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, � ≈ 0.1 −0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ∼ 2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A − S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective. Subject headings: Galaxies: spiral – Galaxies: structure – Galaxies: photometry – Galaxies: interactions – Galaxies: fundamental parameters– Galaxies: morphology – Galaxies: general
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
arXiv: Astrophysics, 2004Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BVRI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, t ~ 0.1 - 0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ~2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A-S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective.
Haitao Yang - One of the best experts on this subject based on the ideXlab platform.
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co Projection Plane based 3 d padding for polyhedron Projection for 360 degree video
International Conference on Multimedia and Expo, 2017Co-Authors: Li Li, Haitao Yang, Zhu Li, Houqiang LiAbstract:The polyhedron Projection for 360-degree video is becoming more and more popular since it can lead to much less geometry distortion compared with the equirectangular Projection. However, in the polyhedron Projection, we can observe very obvious texture discontinuity in the area near the face boundary. Such a texture discontinuity may lead to serious quality degradation when motion compensation crosses the discontinuous face boundary. To solve this problem, in this paper, we first propose to fill the corresponding neighboring faces in the suitable positions as the extension of the current face to keep approximated texture continuity. Then a co-Projection-Plane based 3-D padding method is proposed to project the reference pixels in the neighboring face to the current face to guarantee exact texture continuity. Under the proposed scheme, the reference pixel is always projected to the same Plane with the current pixel when performing motion compensation so that the texture discontinuity problem can be solved. The proposed scheme is implemented in the reference software of High Efficiency Video Coding. Compared with the existing method, the proposed algorithm can significantly improve the rate-distortion performance. The experimental results obviously demonstrate that the texture discontinuity in the face boundary can be well handled by the proposed algorithm.
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co Projection Plane based 3 d padding for polyhedron Projection for 360 degree video
International Conference on Multimedia and Expo, 2017Co-Authors: Haitao YangAbstract:The polyhedron Projection for 360-degree video is becoming more and more popular since it can lead to much less geometry distortion compared with the equirectangular Projection. However, in the polyhedron Projection, we can observe very obvious texture discontinuity in the area near the face boundary. Such a texture discontinuity may lead to serious quality degradation when motion compensation crosses the discontinuous face boundary. To solve this problem, in this paper, we first propose to fill the corresponding neighboring faces in the suitable positions as the extension of the current face to keep approximated texture continuity. Then a co-Projection-Plane based 3-D padding method is proposed to project the reference pixels in the neighboring face to the current face to guarantee exact texture continuity. Under the proposed scheme, the reference pixel is always projected to the same Plane with the current pixel when performing motion compensation so that the texture discontinuity problem can be solved. The proposed scheme is implemented in the reference software of High Efficiency Video Coding. Compared with the existing method, the proposed algorithm can significantly improve the rate-distortion performance. The experimental results obviously demonstrate that the texture discontinuity in the face boundary can be well handled by the proposed algorithm.
Vladimir Avilareese - One of the best experts on this subject based on the ideXlab platform.
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
The Astronomical Journal, 2005Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BV RI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, � ≈ 0.1 −0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ∼ 2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A − S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective. Subject headings: Galaxies: spiral – Galaxies: structure – Galaxies: photometry – Galaxies: interactions – Galaxies: fundamental parameters– Galaxies: morphology – Galaxies: general
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
arXiv: Astrophysics, 2004Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BVRI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, t ~ 0.1 - 0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ~2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A-S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective.
Christopher J Conselice - One of the best experts on this subject based on the ideXlab platform.
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
The Astronomical Journal, 2005Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BV RI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, � ≈ 0.1 −0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ∼ 2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A − S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective. Subject headings: Galaxies: spiral – Galaxies: structure – Galaxies: photometry – Galaxies: interactions – Galaxies: fundamental parameters– Galaxies: morphology – Galaxies: general
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the structural properties of isolated galaxies spiral spiral pairs and mergers the robustness of galaxy morphology during secular evolution
arXiv: Astrophysics, 2004Co-Authors: H M Hernandeztoledo, Vladimir Avilareese, Christopher J Conselice, I PuerariAbstract:We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BVRI bands and compare with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the Projections of CAS parameter space to compare these samples. We find that the CAS parameters of paired galaxies are correlated with the projected separations of the pair. For the widest and closest pairs, the CAS parameters tend to be similar to those of isolated and ongoing major mergers (ULIRGs), respectively. Our results imply that galaxy CAS morphology is a robust quantity that only changes significantly during a strong interaction or major merger. The typical time-scale for this change in our paired sample, based on dynamical friction arguments, is short, t ~ 0.1 - 0.5 Gyr. We find average enhancement factors for the spiral pair asymmetries and clumpiness values of ~2.2 and 1.5. The S parameter, which is related to star formation activity, has a moderate level of enhancement suggesting that this activity in modern spirals depends more on internal processes than on external conditions. We furthermore test the statistical criterion for picking up interacting galaxies in an automated way by using the A-S Projection Plane. The diversity of our spiral pair sample in the CAS space suggests that structural/SF/morphological properties of interacting galaxies change abruptly only when the interaction becomes very strong and that the criteria for finding galaxies involved in major mergers from Conselice (2003) is effective.
