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This paper quantifies an error source that limits the accuracy of lidar scan matching, particularly for voxel-based methods. Lidar scan matching, which is used in dead reckoning (also known as lidar odometry) and mapping, computes the…

Robotics · Computer Science 2024-01-25 Jason Rife , Matthew McDermott

We present a new method for detecting and correcting systematic errors in the distances to stars when both proper motions and line-of-sight velocities are available. The method, which is applicable for samples of 200 or more stars that have…

Astrophysics of Galaxies · Physics 2015-06-03 Ralph Schoenrich , James Binney , Martin Asplund

Large-scale transmission radiography scanners are used to image vehicles and cargo containers. Acquired images are inspected for threats by a human operator or a computer algorithm. To make accurate detections, it is important that image…

Instrumentation and Detectors · Physics 2016-08-15 Thomas W. Rogers , James Ollier , Edward J. Morton , Lewis D. Griffin

The idea of using stellar photometry for atmospheric monitoring for optical experiments in high-energy astrophysics is seemingly straightforward, but reaching high precision of the order of 0.01 in the determination of the vertical aerosol…

Accurate photometric redshifts are among the key requirements for precision weak lensing measurements. Both the large size of the Sloan Digital Sky Survey (SDSS) and the existence of large spectroscopic redshift samples that are…

Existing methods for obtaining flat field rely on observed data collected under specific observation conditions to determine the flat field. However, the telescope pointing and the column fixed pattern noise of the CMOS detector change…

Instrumentation and Methods for Astrophysics · Physics 2025-03-21 YaHui Jin , Hui Liu , KaiFan Ji , ZhenYu Jin , WeiJie Meng

The extraction of fibers from dMRI data typically produces a large number of fibers, it is common to group fibers into bundles. To this end, many specialized distance measures, such as MCP, have been used for fiber similarity. However,…

Computer Vision and Pattern Recognition · Computer Science 2017-09-20 Kuldeep Kumar , Pietro Gori , Benjamin Charlier , Stanley Durrleman , Olivier Colliot , Christian Desrosiers

In fiber-fed galaxy redshift surveys, the finite size of the fiber plugs prevents two fibers from being placed too close to one another, limiting the ability of studying galaxy clustering on all scales. We present a new method for…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-07 Hong Guo , Idit Zehavi , Zheng Zheng

The paper presents a concept of a dynamic accuracy estimation method, in which the localization errors are derived based on the measurement results used by the positioning algorithm. The concept was verified experimentally in a…

Signal Processing · Electrical Eng. & Systems 2026-01-06 Marcin Kolakowski , Vitomir Djaja-Josko

In the maintenance of optical fiber networks, there is a growing demand for high-precision measurement of optical loss distribution and fault locations over long distances. In this study, we propose an OCDR method incorporating periodic…

We describe techniques for photometric calibration of optical spectra obtained with the MMT's fiber-fed spectrograph, Hectospec. The atmospheric dispersion compensation prisms built into the MMT's f/5 wide field corrector effectively…

This work demonstrates a computational method for predicting the light propagation through a single multimode fiber using a deep neural network. The experiment for gathering training and testing data is performed with a digital micro-mirror…

Optics · Physics 2018-12-10 Pengfei Fan , Liang Deng , Lei Su

The image quality budget of many telescopes can have substantial contributions from local seeing, both``mirror'' and ``dome'', which arise from turbulence and temperature variations that are difficult to quantify, measure directly, and…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Christopher W. Stubbs

We report on an easy-to-evaluate expression for the prediction of the bend-loss for a large mode area photonic crystal fiber (PCF) with a triangular air-hole lattice. The expression is based on a recently proposed formulation of the…

Speckle imaging is a well known method to achieve diffraction-limited (DL) imaging from ground-based telescopes. The traditional observing method for speckle has been to observe a single, unresolved, source per telescope pointing over a…

Instrumentation and Methods for Astrophysics · Physics 2018-06-04 James W. Davidson , Elliott P. Horch , Steven R. Majewski

In optical metrological protocols to measure physical quantities, it is, in principle, always beneficial to increase photon number to improve measurement precision. However, practical constraints prevent arbitrary increase of n due to the…

The complete 10-year survey from the Large Synoptic Survey Telescope (LSST) will image $\sim$ 20,000 square degrees of sky in six filter bands every few nights, bringing the final survey depth to $r\sim27.5$, with over 4 billion well…

The paper proposes a method of finding the beam loss locations in a linac. If the beam is scraped at an aperture limitation, moving its centroid with two dipole correctors located upstream and oscillating in sync produces a line at the…

Accelerator Physics · Physics 2019-05-02 Alexander Shemyakin

Focal ratio degradation (FRD), the increase of light's focal ratio between the input into an optical fiber and the output, is important to characterize for astronomical spectrographs due to its effects on throughput and the point spread…

Instrumentation and Methods for Astrophysics · Physics 2020-06-22 Brent Belland , James Gunn , Dan Reiley , Judith Cohen , Evan Kirby , Antonio Cesar de Oliveira , Ligia Souza de Oliveira , Mitsuko Roberts , Michael Seiffert

Fiber network modeling can be used for studying mechanical properties of paper. The individual fibers and the bonds in-between constitute a detailed representation of the material. However, detailed microscale fiber network models must be…

Numerical Analysis · Mathematics 2020-04-29 Morgan Görtz , Gustav Kettil , Axel Målqvist , Andreas Mark , Fredrik Edelvik
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