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A number of experiments are set to measure the 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR). The common denominator of these experiments are the large data sets produced, contaminated by various instrumental…

We present a stochastic, limited-memory Broyden Fletcher Goldfarb Shanno (LBFGS) algorithm that is suitable for handling very large amounts of data. A direct application of this algorithm is radio interferometric calibration of raw data at…

Instrumentation and Methods for Astrophysics · Physics 2019-04-16 Sarod Yatawatta , Lukas De Clercq , Hanno Spreeuw , Faruk Diblen

We introduce CALAMITY, a precision bandpass calibration method for radio interferometry. CALAMITY can solve for direction independent gains with arbitrary frequency structure to the high precision required for 21 cm cosmology with minimal…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Aaron Ewall-Wice , Joshua S. Dillon , Bharat Gehlot , Aaron Parsons , Tyler Cox , Daniel C. Jacobs

Despite extensive research on neural network calibration, existing methods typically apply global transformations that treat all predictions uniformly, overlooking the heterogeneous reliability of individual predictions. Furthermore, the…

Machine Learning · Computer Science 2025-10-22 Hassan Gharoun , Mohammad Sadegh Khorshidi , Kasra Ranjbarigderi , Fang Chen , Amir H. Gandomi

We present a new procedure for the internal (night-to-night) calibration of time series spectra, with specific applications to optical AGN reverberation mapping data. The traditional calibration technique assumes that the narrow…

Instrumentation and Methods for Astrophysics · Physics 2017-12-19 M. M. Fausnaugh

In this paper, we investigate the impact of survey strategy on the performance of self-calibration when the goal is to produce accurate photometric catalogs from wide-field imaging surveys. This self-calibration technique utilizes multiple…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Rory Holmes , David W. Hogg , Hans-Walter Rix

Excalibur is a non-parametric, hierarchical framework for precision wavelength-calibration of spectrographs. It is designed with the needs of extreme-precision radial velocity (EPRV) in mind, which require that instruments be calibrated or…

Instrumentation and Methods for Astrophysics · Physics 2021-01-27 L. L. Zhao , D. W. Hogg , M. Bedell , D. A. Fischer

In recent years, multiple Light Detection and Ranging (LiDAR) systems have grown in popularity due to their enhanced accuracy and stability from the increased field of view (FOV). However, integrating multiple LiDARs can be challenging,…

Robotics · Computer Science 2023-11-08 Minwoo Jung , Sangwoo Jung , Ayoung Kim

Observations of 21cm line from neutral hydrogen promise to be an exciting new probe of astrophysics and cosmology during the Cosmic Dawn and through the Epoch of Reionization (EoR) to when dark energy accelerates the expansion of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-24 Tyler A. Cox , Aaron R. Parsons , Joshua S. Dillon , Aaron Ewall-Wice , Robert Pascua

In this paper, we propose a method of targetless and automatic Camera-LiDAR calibration. Our approach is an extension of hand-eye calibration framework to 2D-3D calibration. By using the sensor fusion odometry method, the scaled camera…

Computer Vision and Pattern Recognition · Computer Science 2018-04-17 Ryoichi Ishikawa , Takeshi Oishi , Katsushi Ikeuchi

Sensor calibration, which can be intrinsic or extrinsic, is an essential step to achieve the measurement accuracy required for modern perception and navigation systems deployed on autonomous robots. To date, intrinsic calibration models for…

Robotics · Computer Science 2021-07-29 Jiunn-Kai Huang , Chenxi Feng , Madhav Achar , Maani Ghaffari , Jessy W. Grizzle

Accurate and reliable sensor calibration is essential to fuse LiDAR and inertial measurements, which are usually available in robotic applications. In this paper, we propose a novel LiDAR-IMU calibration method within the continuous-time…

Robotics · Computer Science 2022-05-09 Jiajun Lv , Xingxing Zuo , Kewei Hu , Jinhong Xu , Guoquan Huang , Yong Liu

In 21 cm cosmology, precision calibration is key to the separation of the neutral hydrogen signal from very bright but spectrally-smooth astrophysical foregrounds. The Hydrogen Epoch of Reionization Array (HERA), an interferometer…

In this work, we implement a relatively new analytical technique, the Improved Amplitude-Frequency Formulation (IAFF) method, approach for solving accurate approximate analytical solutions for strong nonlinear oscillators, which may contain…

Dynamical Systems · Mathematics 2021-10-05 R. Azami , D. D. Ganji , A. G. Davodi , H. Babazadeh

Precise collaboration in vision-based dual-arm robot systems requires accurate system calibration. Recent dual-robot calibration methods have achieved strong performance by simultaneously solving multiple coordinate transformations.…

Robotics · Computer Science 2026-03-17 Tianyu Huang , Bohan Yang , Bin Li , Wenpan Li , Haoang Li , Wenlong Li , Yun-Hui Liu

The light field camera is useful for computer graphics and vision applications. Calibration is an essential step for these applications. After calibration, we can rectify the captured image by using the calibrated camera parameters.…

Computer Vision and Pattern Recognition · Computer Science 2014-07-17 Yichao Xu , Kazuki Maeno , Hajime Nagahara , Rin-ichiro Taniguchi

Very Long Baseline Interferometric (VLBI) observations of quasar jets enable one to measure many theoretically expected effects. Estimating the significance of observational findings is complicated by the correlated noise in the image…

Instrumentation and Methods for Astrophysics · Physics 2018-10-22 I. N. Pashchenko

Bayesian Model Calibration is used to revisit the problem of scaling factor calibration for semi-empirical correction of ab initio calculations. A particular attention is devoted to uncertainty evaluation for scaling factors, and to their…

Data Analysis, Statistics and Probability · Physics 2009-01-12 Pascal Pernot

Broadband femtosecond-laser frequency combs are filtered to spectrographically resolvable frequency-mode spacing, and the limitations of using cavities for spectral filtering are considered. Data and theory are used to show implications to…

Quantum Physics · Physics 2009-11-13 D. A. Braje , M. S. Kirchner , S. Osterman , T. Fortier , S. A. Diddams

There exists the phase ambiguity problem in the coherent beam combining (CBC) system with centrosymmetric arrays, which means that multiple different piston aberrations may generate the same far-field image. This will cause that the…

Optics · Physics 2021-12-02 H. Jia , J. Zuo , Q. Bao , C. Geng , A. Tang , Y. Luo , Z. Li , J. Jiang , F. Li , F. Zou , X. Yang , Z. Pan , J. Jiang , J. Ren , X. Li
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