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In the first paper of this series, we studied the effect of baryon acoustic oscillations (BAO), redshift space distortions (RSD) and weak lensing (WL) on measurements of angular cross-correlations in narrow redshift bins. Paper-II presented…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-09 Martin Eriksen , Enrique Gaztanaga

This paper aims to improve the performance and positioning accuracy of a robot by using the particle filter method. The laser range information is a wireless navigation system mainly used to measure, position, and control autonomous robots.…

Robotics · Computer Science 2021-10-29 Rashid Ali , Dil Nawaz Hakro , Yongping He , Wenpeng Fu , Zhiqiang Cao

Sample selection is a necessary preparation for weak lensing measurement. It is well-known that selection itself may introduce bias in the measured shear signal. Using image simulation and the Fourier_Quad shear measurement pipeline, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 Hekun Li , Jun Zhang , Dezi Liu , Wentao Luo , Jiajun Zhang , Fuyu Dong , Zhi Shen , Haoran Wang

Fiber-like features are an important aspect of breast imaging. Vessels and ducts are present in all breast images, and spiculations radiating from a mass can indicate malignancy. Accordingly, fiber objects are one of the three types of…

Medical Physics · Physics 2019-04-09 Sean D. Rose , Emil Y. Sidky , Ingrid Reiser , Xiaochuan Pan

Accurate estimates of Instrument Spectral Response Functions (ISRFs) are crucial in order to have a good characterization of high resolution spectrometers. Spectrometers are composed of different optical elements that can induce errors in…

Numerical Analysis · Mathematics 2024-04-09 Jihanne El Haouari , Jean-Michel Gaucel , Christelle Pittet , Jean-Yves Tourneret , Herwig Wendt

Focal Ration Degradation (FRD) is a change in light angular distribution caused by fiber optics. FRD is important to fiber-fed, spectroscopic astronomical systems because it can cause loss of signal, degradation in spectral resolution, or…

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

Integral-field-spectroscopy and multi-object-spectroscopy provide the high multiplex gain required for efficient use of the upcoming generation of extremely large telescopes. We present instrument developments and designs for both concepts,…

Astrophysics · Physics 2007-05-23 F. Eisenhauer , M. Tecza , N. Thatte , S. Mengel , R. Hofmann , R. Genzel

The availability of positional information is of great importance in many commercial, governmental, and military applications. Localization is commonly accomplished through the use of radio communication between mobile devices (agents) and…

Information Theory · Computer Science 2016-11-15 Yuan Shen , Henk Wymeersch , Moe Z. Win

A low-complexity model for signal quality prediction in a nonlinear fiber-optical network is developed. The model, which builds on the Gaussian noise model, takes into account the signal degradation caused by a combination of chromatic…

Optics · Physics 2015-01-07 Pontus Johannisson , Erik Agrell

We present a method to determine the static aberrations in a nearly diffraction-limited spectrograph introduced, for example, by alignment or manufacturing errors. We consider an instrument with two stages separated by a slit or image…

Instrumentation and Methods for Astrophysics · Physics 2022-06-01 B. Sánchez , A. M. Watson , S. Cuevas

In vibration-based condition monitoring, optimal filter design improves fault detection by enhancing weak fault signatures within vibration signals. This process involves optimising a derived objective function from a defined objective. The…

Signal Processing · Electrical Eng. & Systems 2024-05-07 Stephan Schmidt , Daniel N. Wilke , Konstantinos C. Gryllias

The Prime Focus Spectrograph (PFS) is a wide field multi-fiber spectrograph using the prime focus of the Subaru telescope, which is capable of observing up to 2400 astronomical objects simultaneously. The instrument control software will…

Instrumentation and Methods for Astrophysics · Physics 2012-10-11 Atsushi Shimono , Naoyuki Tamura , Hajime Sugai , Hiroshi Karoji

Fiber modal noise is a performance limiting factor in high-resolution spectroscopy, both with respect to achieving high signal-to-noise ratios or when targeting high-precision radial velocity measurements, with multi-mode fiber-fed…

Instrumentation and Methods for Astrophysics · Physics 2020-12-16 Gert Raskin , Jacob Pember , Dmytro Rogozin , Christian Schwab , David Coutts

I propose an analysis method, based on spin-spherical harmonics and spherical Bessel functions, for large-scale weak lensing surveys which have source distance information through photometric redshifts. I show that the distance information…

Astrophysics · Physics 2009-11-07 Alan Heavens

Automated fiber placement (AFP) is an advanced manufacturing technology that increases the rate of production of composite materials. At the same time, the need for adaptable and fast inline control methods of such parts raises. Existing…

Computer Vision and Pattern Recognition · Computer Science 2019-10-14 Sebastian Zambal , Christoph Heindl , Christian Eitzinger , Josef Scharinger

For photoacoustic image reconstruction, certain parameters such as sensor positions and speed of sound have a major impact in the reconstruction process and must be carefully determined before data acquisition. Uncertainties in these…

Signal Processing · Electrical Eng. & Systems 2021-11-24 L. Hirsch , M. G. Gonzalez , L. Rey Vega

Modern extreme adaptive optics (AO) systems achieving diffraction-limited performance open up new possibilities for instrumentation. Especially important for the fields of spectroscopy and interferometry is that it enables the prospect to…

The fields of view of Extremely Large Telescopes will contain vast numbers of spatial sampling elements (spaxels) as their Adaptive Optics systems approach the diffraction limit over wide fields. Since this will exceed the detection…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 G. J. Murray , J. R. Allington-Smith

Large-scale surveys make huge amounts of photometric data available. Because of the sheer amount of objects, spectral data cannot be obtained for all of them. Therefore it is important to devise techniques for reliably estimating physical…

Instrumentation and Methods for Astrophysics · Physics 2017-03-22 Kristoffer Stensbo-Smidt , Fabian Gieseke , Christian Igel , Andrew Zirm , Kim Steenstrup Pedersen
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