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相关论文: Rotation Invariant Descriptors for Galaxy Morpholo…

200 篇论文

We study a sample of 112 galaxies of various Hubble types imaged in the Two Micron All Sky Survey (2MASS) in the Near-Infra Red (NIR; 1-2 $\mu$m) $J$, $H$, and $K_s$ bands. The sample contains (optically classified) 32 elliptical, 16…

天体物理学 · 物理学 2009-11-10 Nurur Rahman , Sergei F. Shandarin

In this proceeding we make use of the two-dimensional stellar kinematics of a representative sample of E and S0 galaxies obtained with the SAURON integral-field spectrograph to reveal that early-type galaxies appear in two broad flavours,…

Using the galaxy data of the Sloan Digital Sky Survey Data Release 8 (SDSS DR8), I explore whether the concentration index is a good morphological classification tool and find that a reasonably pure late-type galaxy sample can be…

星系天体物理 · 物理学 2015-06-12 Xin-Fa Deng

The morphological diversity of galaxies is a relevant probe of galaxy evolution and cosmological structure formation. However, in large sky surveys, even the morphological classification of galaxies into two classes, like late-type (LT) and…

We explore the use of the tangential component of weak lensing shear to characterize the ellipticity of clusters of galaxies. We introduce an ellipticity estimator, and quantify its properties for isolated clusters from LCDM N-body…

天体物理学 · 物理学 2009-11-13 A. E. Schulz , Joseph Hennawi , Martin White

A homogeneous sample of galaxy redshifts in the core regions (R < 0.5 h$^{-1}$ Mpc) of 12 clusters is used to measure the frequency of substructure with different tests. In 50 % of the cases substructure is detected, a frequency which…

天体物理学 · 物理学 2007-05-23 P. Stein

We employ the XGBoost machine learning (ML) method for the morphological classification of galaxies into two (early-type, late-type) and five (E, S0--S0a, Sa--Sb, Sbc--Scd, Sd--Irr) classes, using a combination of non-parametric…

We conduct a systematic robustness analysis of the unsupervised machine learning module within the hybrid framework \texttt{USmorph}. This module automatically discovers morphological structures from large-scale galaxy images, forming the…

星系天体物理 · 物理学 2026-05-21 Guanwen Fang , Xiaolei Yin , Yirui Zheng , Zesen Lin , Shiwei Zhu , Jie Song , Chichun Zhou , Xu Kong

In this study, we report on the analysis of 701 stars in a solar vicinity defined in three categories namely subsolar, solar, and supersolar with rotation periods between 1 and 70 days, based on rotational modulation signatures inferred…

Performance of neural networks can be significantly improved by encoding known invariance for particular tasks. Many image classification tasks, such as those related to cellular imaging, exhibit invariance to rotation. We present a novel…

机器学习 · 统计学 2018-06-01 Benjamin Chidester , Minh N. Do , Jian Ma

In order to obtain morphological information of unlabeled galaxies, we present an unsupervised machine-learning (UML) method for morphological classification of galaxies, which can be summarized as two aspects: (1) the methodology of…

星系天体物理 · 物理学 2022-02-02 C. C. Zhou , Y. Z. Gu , G. W. Fang , Z. S. Lin

In this paper, a deep convolutional neural network architecture for galaxies classification is presented. The galaxy can be classified based on its features into main three categories Elliptical, Spiral, and Irregular. The proposed deep…

计算机视觉与模式识别 · 计算机科学 2017-09-08 Nour Eldeen M. Khalifa , Mohamed Hamed N. Taha , Aboul Ella Hassanien , I. M. Selim

We present an enhanced unsupervised machine learning (UML) module within our previous \texttt{USmorph} classification framework featuring two components: (1) hierarchical feature extraction via a pre-trained ConvNeXt convolutional neural…

星系天体物理 · 物理学 2025-12-19 Guanwen Fang , Shiwei Zhu , Jun Xu , Shiying Lu , Chichun Zhou , Yao Dai , Zesen Lin , Xu Kong

In this work we introduce a physically motivated method of performing disc/spheroid decomposition of simulated galaxies, which we apply to the Eagle sample. We make use of the HEALPix package to create Mollweide projections of the angular…

星系天体物理 · 物理学 2021-01-14 Dimitrios Irodotou , Peter A. Thomas

This study addresses the challenge of classifying cell shapes from noisy contours, such as those obtained through cell instance segmentation of histological images. We assess the performance of various features for shape classification,…

计算机视觉与模式识别 · 计算机科学 2024-11-04 Valentina Vadori , Antonella Peruffo , Jean-Marie Graïc , Livio Finos , Enrico Grisan

In recent decades, large-scale sky surveys such as Sloan Digital Sky Survey (SDSS) have resulted in generation of tremendous amount of data. The classification of this enormous amount of data by astronomers is time consuming. To simplify…

天体物理仪器与方法 · 物理学 2022-11-02 Sarvesh Gharat , Yogesh Dandawate

Galaxy morphology encodes key information about formation and evolution. Large imaging surveys require automated, reproducible methods beyond visual inspection. Non--parametric indices provide an useful framework, but their performance must…

Aims. This work investigates the potential of using the wavelength-dependence of galaxy structural parameters (S\'ersic index, n, and effective radius, Re) to separate galaxies into distinct types. Methods. A sample of nearby galaxies with…

星系天体物理 · 物理学 2015-05-13 M. Vika , B. Vulcani , S. P. Bamford , B. Häußler , A. L. Rojas

Quantitative morphological classification of galaxies is important for understanding the origin of type frequency and correlations with environment. But galaxy morphological classification is still mainly done visually by dedicated…

The structural information of spiral galaxies such as the spiral arm number, offer valuable insights into their formation processes and physical roles in galaxy evolution. We developed classifiers based on CNNs using variants of the…

星系天体物理 · 物理学 2024-12-17 Ming Wei Lee , John Y. H. Soo , Syarawi M. H. Sharoni