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This paper presents a new variable selection approach integrated with Gaussian process (GP) regression. We consider a sparse projection of input variables and a general stationary covariance model that depends on the Euclidean distance…

Machine Learning · Computer Science 2020-08-26 Chiwoo Park , David J. Borth , Nicholas S. Wilson , Chad N. Hunter

In this paper, we study a 2D tomography problem for point source models with random unknown view angles. Rather than recovering the projection angles, we reconstruct the model through a set of rotation-invariant features that are estimated…

Signal Processing · Electrical Eng. & Systems 2018-11-27 Mona Zehni , Shuai Huang , Ivan Dokmanić , Zhizhen Zhao

We geometrically analyze the problem of estimating parameters related to the shape and size of a two-dimensional target object on the plane by using randomly distributed distance sensors whose locations are unknown. Based on the analysis…

Information Theory · Computer Science 2017-07-20 Hiroshi Saito , Hirotada Honda

Computed tomography is a method for synthesizing volumetric or cross-sectional images of an object from a collection of projections. Popular reconstruction methods for computed tomography are based on idealized models and assumptions that…

Numerical Analysis · Mathematics 2022-03-03 Frederik H. Pedersen , Jakob S. Jørgensen , Martin S. Andersen

We propose a method to achieve the geometric calibration of cone-beam imaging and delivery systems in radiation therapy; our approach applies to devices where an X-ray source and a flat-panel detector, facing each other, move in circular…

Medical Physics · Physics 2007-05-23 Evangelos Matsinos , Wolfgang Kaissl

In industrial applications, it is common to scan objects on a moving conveyor belt. If slice-wise 2D computed tomography (CT) measurements of the moving object are obtained we call it a sequential scanning geometry. In this case, each slice…

Signal Processing · Electrical Eng. & Systems 2023-11-10 Sebastian Springer , Aldo Glielmo , Angelina Senchukova , Tomi Kauppi , Jarkko Suuronen , Lassi Roininen , Heikki Haario , Andreas Hauptmann

Optical scatterometry is a method to measure the size and shape of periodic micro- or nanostructures on surfaces. For this purpose the geometry parameters of the structures are obtained by reproducing experimental measurement results…

Computational Physics · Physics 2020-06-24 Philipp-Immanuel Schneider , Martin Hammerschmidt , Lin Zschiedrich , Sven Burger

Many problems in computer vision can be formulated as geometric estimation problems, i.e. given a collection of measurements (e.g. point correspondences) we wish to fit a model (e.g. an essential matrix) that agrees with our observations.…

Computer Vision and Pattern Recognition · Computer Science 2024-05-14 Felix Rydell , Angélica Torres , Viktor Larsson

Procedural material models have been gaining traction in many applications thanks to their flexibility, compactness, and easy editability. We explore the inverse rendering problem of procedural material parameter estimation from…

Graphics · Computer Science 2025-04-22 Yu Guo , Milos Hasan , Lingqi Yan , Shuang Zhao

Antenna array calibration is necessary to maintain the high fidelity of beam patterns across a wide range of advanced antenna systems and to ensure channel reciprocity in time division duplexing schemes. Despite the continuous development…

Signal Processing · Electrical Eng. & Systems 2023-05-26 Sergey S. Tambovskiy , Gábor Fodor , Hugo M. Tullberg

The main objective of this work is to describe a general and original approach for computing an off-line solution for a set of parameters describing the geometry of the domain. That is, a solution able to include information for different…

Numerical Analysis · Mathematics 2019-09-26 Ruben Sevilla , Sergio Zlotnik , Antonio Huerta

We present a cost-efficient and versatile method to map an unknown 3D freeform surface using only sparse measurements while the end-effector of a robotic manipulator moves along the surface. The geometry is locally approximated by a plane,…

Robotics · Computer Science 2021-10-08 Manuel Amersdorfer , Thomas Meurer

A common task is the determination of system parameters from spectroscopy, where one compares the experimental spectrum with calculated spectra, that depend on the desired parameters. Here we discuss an approach based on a machine learning…

Quantum Physics · Physics 2022-05-04 Farhad Taher-Ghahramani , Fulu Zheng , Alexander Eisfeld

We examine in this paper the problem of image registration from the new perspective where images are given by sparse approximations in parametric dictionaries of geometric functions. We propose a registration algorithm that looks for an…

Computer Vision and Pattern Recognition · Computer Science 2013-12-31 Alhussein Fawzi , Pascal Frossard

We develop a Bayesian approach called Bayesian projected calibration to address the problem of calibrating an imperfect computer model using observational data from a complex physical system. The calibration parameter and the physical…

Methodology · Statistics 2019-02-08 Fangzheng Xie , Yanxun Xu

In this paper we discuss an application of Stochastic Approximation to statistical estimation of high-dimensional sparse parameters. The proposed solution reduces to resolving a penalized stochastic optimization problem on each stage of a…

Machine Learning · Statistics 2022-10-25 Sasila Ilandarideva , Yannis Bekri , Anatoli Juditsky , Vianney Perchet

Calibration or parameter identification is used with computational mechanics models related to observed data of the modeled process to find model parameters such that good similarity between model prediction and observation is achieved. We…

Computational Engineering, Finance, and Science · Computer Science 2022-12-26 Harald Willmann , Jonas Nitzler , Sebastian Brandstaeter , Wolfgang A. Wall

X-ray tomographic image reconstruction consists of determining an object function from its projections. In many applications such as non-destructive testing, we look for a fault region (air) in a homogeneous, known background (metal). The…

Data Analysis, Statistics and Probability · Physics 2007-05-23 A. Mohammad-Djafari , Ken Sauer

Surface parameterization is a fundamental concept in fields such as differential geometry and computer graphics. It involves mapping a surface in three-dimensional space onto a two-dimensional parameter space. This process allows for the…

Numerical Analysis · Mathematics 2024-12-16 Shu-Yung Liu , Mei-Heng Yueh

Global quantum sensing enables parameter estimation across arbitrary ranges with a finite number of measurements. Among the various existing formulations, the Bayesian paradigm stands as a flexible approach for optimal protocol design under…

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