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Generic event boundary detection (GEBD) aims to identify natural boundaries in a video, segmenting it into distinct and meaningful chunks. Despite the inherent subjectivity of event boundaries, previous methods have focused on deterministic…

Computer Vision and Pattern Recognition · Computer Science 2025-08-19 Jaejun Hwang , Dayoung Gong , Manjin Kim , Minsu Cho

In this paper, we analyze in detail with numerical simulations how the mask effect can influence the weak lensing peak statistics reconstructed from the shear measurement of background galaxies. It is found that high peak fractions are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Xiangkun Liu , Qiao Wang , Chuzhong Pan , Zuhui Fan

Weak lensing statistics is typically measured as weighted sum of shear estimators or their products (shear-shear correlation). The weighting schemes are designed in the hope of minimizing the statistical error without introducing systematic…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Jun Zhang , Pengjie Zhang , Wentao Luo

We derive a new relation between cosological distances, valid in any (statistically) isotropic space-time and independent of cosmological parameters or even the validity of the field equation of General Relativity. In particular, this…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-03 Peter Schneider

Boundaries are among the primary visual cues used by human and computer vision systems. One of the key problems in boundary detection is the label representation, which typically leads to class imbalance and, as a consequence, to thick…

Computer Vision and Pattern Recognition · Computer Science 2022-09-09 Edoardo Mello Rella , Ajad Chhatkuli , Yun Liu , Ender Konukoglu , Luc Van Gool

The proposed two-dimensional geometrically exact beam element extends our previous work by including the effects of shear distortion, and also of distributed forces and moments acting along the beam. The general flexibility-based…

Numerical Analysis · Mathematics 2025-08-06 Milan Jirasek , Martin Horak , Emma La Malfa Ribolla , Chiara Bonvissuto

We show, using the pseudo-$C_\ell$ technique, how to estimate cosmic shear and galaxy-galaxy lensing power spectra that are insensitive to the effects of multiple sources of lensing bias including source-lens clustering, magnification bias…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-12 Christopher A. J. Duncan , Michael L. Brown

This paper proposes a novel method which combines both median filter and simple standard deviation to accomplish an excellent edge detector for image processing. First of all, a denoising process must be applied on the grey scale image…

Computer Vision and Pattern Recognition · Computer Science 2013-04-24 Firas A. Jassim

This paper proposes a novel method for high-quality image segmentation of both objects and scenes. Inspired by the dilation and erosion operations in morphological image processing techniques, the pixel-level image segmentation problems are…

Computer Vision and Pattern Recognition · Computer Science 2021-12-15 Hao He , Xiangtai Li , Yibo Yang , Guangliang Cheng , Yunhai Tong , Lubin Weng , Zhouchen Lin , Shiming Xiang

We investigate methods for determining if a planar surface contains geometric deviations (e.g., protrusions, objects, divots, or cliffs) using only an instantaneous measurement from a miniature optical time-of-flight sensor. The key to our…

Robotics · Computer Science 2024-08-08 Carter Sifferman , William Sun , Mohit Gupta , Michael Gleicher

We present simulations of a cosmic shear survey and show how the survey geometry influences the accuracy of determination of cosmological parameters. We numerically calculate the full covariance matrices Cov of two-point statistics of…

Astrophysics · Physics 2009-11-10 Martin Kilbinger , Peter Schneider

As imaging surveys progress in exploring the large-scale structure of the Universe through the use of weak gravitational lensing, achieving subpercent accuracy in estimating shape distortions caused by lensing, or shear, is imperative for…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-22 Andy Park , Xiangchong Li , Rachel Mandelbaum

In this paper, a color edge detection strategy based on collaborative filtering combined with multiscale gradient fusion is proposed. The block-matching and 3D (BM3D) filter are used to enhance the sparse representation in the transform…

Computer Vision and Pattern Recognition · Computer Science 2024-09-04 Zhuoyue Wang , Yiyi Tao , Danqing Ma , Jiajing Chen

Collider events with multi-stage cascade decays fill out the kinematically allowed region in phase space with a density that is enhanced at the boundary. The boundary encodes all available information about the spectrum and is well…

High Energy Physics - Phenomenology · Physics 2017-03-08 Baris Altunkaynak , Can Kilic , Matthew D. Klimek

We study the effect of an externally imposed oscillatory shear on the motion of a grain boundary that separates differently oriented domains of the lamellar phase of a diblock copolymer. A direct numerical solution of the Swift-Hohenberg…

Soft Condensed Matter · Physics 2009-11-10 Zhi-Feng Huang , Jorge Vinals

Precision weak gravitational lensing experiments require measurements of galaxy shapes accurate to <1 part in 1000. We investigate measurement biases, noted by Voigt and Bridle (2009) and Melchior et al. (2009), that are common to shape…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Gary M. Bernstein

Problems with localized nonhomogeneous material properties arise frequently in many applications and are a well-known source of difficulty in numerical simulations. In certain applications (including additive manufacturing), the physics of…

Numerical Analysis · Mathematics 2020-04-22 Alex Viguerie , Silvia Bertoluzza , Ferdinando Auricchio

In this paper we derive a full expression for the propagation of weak lensing shape measurement biases into cosmic shear power spectra including the effect of missing data. We show using simulations that terms higher than first order in…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-16 T. D. Kitching , A. C. Deshpande , P. L. Taylor

The measurement of shape parameters of sources in astronomical images is usually performed by assuming that the underlying noise is uncorrelated. Spatial noise correlation is however present in practice due to various observational effects…

Astrophysics · Physics 2007-05-23 A. Refregier , S. T. Brown

Using new photometric and spectroscopic data in the fields of nine strong gravitational lenses that lie in galaxy groups, we analyze the effects of both the local group environment and line-of-sight galaxies on the lens potential. We use…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Kenneth C. Wong , Charles R. Keeton , Kurtis A. Williams , Ivelina G. Momcheva , Ann I. Zabludoff
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