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Contrastive Language-Image Pre-Training (CLIP) is highly instrumental in machine learning applications within a large variety of domains. We investigate the geometry of this embedding, which is still not well understood. We examine the raw…

Computer Vision and Pattern Recognition · Computer Science 2025-05-27 Meir Yossef Levi , Guy Gilboa

We consider geometric multigrid methods for the solution of linear systems arising from isogeometric discretizations of elliptic partial differential equations. For classical finite elements, such methods are well known to be fast solvers…

Numerical Analysis · Mathematics 2017-05-16 Clemens Hofreither , Stefan Takacs , Walter Zulehner

Path planning has long been one of the major research areas in robotics, with PRM and RRT being two of the most effective classes of planners. Though generally very efficient, these sampling-based planners can become computationally…

Robotics · Computer Science 2023-05-26 Sipu Ruan , Karen L. Poblete , Hongtao Wu , Qianli Ma , Gregory S. Chirikjian

Algorithms for the computation of the forward and inverse geodesic problems for an ellipsoid of revolution are derived. These are accurate to better than 15 nm when applied to the terrestrial ellipsoids. The solutions of other problems…

Geophysics · Physics 2015-03-18 Charles F. F. Karney

The paper aims at proposing the first shape identification and classification algorithm in echolocation. The approach is based on first extracting geometric features from the reflected waves and then matching them with precomputed ones…

Numerical Analysis · Computer Science 2013-08-27 Habib Ammari , Minh Phuong Tran , Han Wang

When determining the parameters of a parametric planar shape based on a single low-resolution image, common estimation paradigms lead to inaccurate parameter estimates. The reason behind poor estimation results is that standard estimation…

Computer Vision and Pattern Recognition · Computer Science 2019-01-30 Wojciech Chojnacki , Zygmunt L. Szpak

We focus on the analysis of planar shapes and solid objects having thin features and propose a new mathematical model to characterize them. Based on our model, that we call an epsilon-shape, we show how thin parts can be effectively and…

Computational Geometry · Computer Science 2018-01-09 Daniela Cabiddu , Marco Attene

We give a deterministic 2^{O(n)} algorithm for computing an M-ellipsoid of a convex body, matching a known lower bound. This has several interesting consequences including improved deterministic algorithms for volume estimation of convex…

Computational Complexity · Computer Science 2014-03-05 Daniel Dadush , Santosh Vempala

Semi-implicit time-stepping schemes for atmosphere and ocean models require elliptic solvers that work efficiently on modern supercomputers. This paper reports our study of the potential computational savings when using mixed precision…

Computational Physics · Physics 2022-10-05 Jan Ackmann , Peter D. Düben , Tim N. Palmer , Piotr K. Smolarkiewicz

Weak gravitational lensing analyses are fundamentally limited by the intrinsic, non-Gaussian distribution of galaxy shapes. We explore alternative statistics for samples of ellipticity measurements that are unbiased, efficient, and robust.…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Merijn Smit , Konrad Kuijken

Efficiently estimating properties of large and strongly coupled quantum systems is a central focus in many-body physics and quantum information theory. While quantum computers promise speedups for many such tasks, near-term devices are…

Quantum Physics · Physics 2021-09-28 Senrui Chen , Wenjun Yu , Pei Zeng , Steven T. Flammia

We propose a multiscale method for elliptic problems on complex domains, e.g. domains with cracks or complicated boundary. For local singularities this paper also offers a discrete alternative to enrichment techniques such as XFEM. We…

Numerical Analysis · Mathematics 2016-11-01 Daniel Elfverson , Mats G. Larson , Axel Målqvist

We propose a multiscale approach for an elliptic multiscale setting with general unstructured diffusion coefficients that is able to achieve high-order convergence rates with respect to the mesh parameter and the polynomial degree. The…

Numerical Analysis · Mathematics 2020-09-03 Roland Maier

Polyhedral estimate is a generic efficiently computable nonlinear in observations routine for recovering unknown signal belonging to a given convex compact set from noisy observation of signal's linear image. Risk analysis and optimal…

Statistics Theory · Mathematics 2022-12-26 Anatoli Juditsky , Arkadi Nemirovski

We consider finite element approximations of ill-posed elliptic problems with conditional stability. The notion of {\emph{optimal error estimates}} is defined including both convergence with respect to mesh parameter and perturbations in…

Numerical Analysis · Mathematics 2024-03-25 Erik Burman , Mihai Nechita , Lauri Oksanen

This paper describes a 2-D graphics algorithm that uses shifts and adds to precisely plot a series of points on an ellipse of any shape and orientation. The algorithm can also plot an elliptic arc that starts and ends at arbitrary angles.…

Graphics · Computer Science 2021-06-14 Jerry R. Van Aken

Differentially private computation often begins with a bound on some $d$-dimensional statistic's $\ell_p$ sensitivity. For pure differential privacy, the $K$-norm mechanism can improve on this approach using a norm tailored to the…

Cryptography and Security · Computer Science 2024-05-22 Matthew Joseph , Alexander Yu

In this work, we investigate data fitting problems with random noises. A randomized progressive iterative regularization method is proposed. It works well for large-scale matrix computations and converges in expectation to the least-squares…

Numerical Analysis · Mathematics 2025-06-05 Dakang Cen , Wenlong Zhang , Junbin Zhong

Most existing distance metric learning methods assume perfect side information that is usually given in pairwise or triplet constraints. Instead, in many real-world applications, the constraints are derived from side information, such as…

Machine Learning · Computer Science 2012-03-19 Kaizhu Huang , Rong Jin , Zenglin Xu , Cheng-Lin Liu

A method is proposed to generate an optimal fit of a number of connected linear trend segments onto time-series data. To be able to efficiently handle many lines, the method employs a stochastic search procedure to determine optimal…

Quantitative Methods · Quantitative Biology 2017-04-11 Myrl G. Marmarelis
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