Abstract: The Breakthrough Starshot project proposes using radiation-pressure propulsion to send multiple spacecraft in the gram-range mass to interstellar targets. There are numerous engineering challenges to accomplishing this mission, but their project discusses speeds and accelerations previously only discussed for cannon projectiles and particle physics experiments. This article examines the problem from first principles to see if the project is even orders-of-magnitude possible. A preliminary check on their numbers seems to confirm that the project is possible in principle. https://stkwans.blogspot.com/2012/04/program-66.html is about the Apollo guidance computer. https://stkwans.blogspot.com/2012/09/a-review-of-adxl345-and-bma180.html
Skyfield computes positions for the stars, planets, and satellites in orbit around the Earth. Its results should agree with the positions generated by the United States Naval Observatory and their Astronomical Almanac to within 0.0005 arcseconds (which equals half a “mas” or milliarcsecond).
Written in pure Python and installs without any compilation.
Supports Python 2.6–2.7 and Python 3.3–3.5.
Has NumPy as its only binary dependency, the fundamental package for scientific computing with Python, whose vector operations make Skyfield efficient.
https://www.johndcook.com/blog/2022/10/21/math-origins/ explains V.I. Arnolds comment
"All mathematics is divided into three parts: cryptography (paid for by CIA, KGB and the like), hydrodynamics (supported by manufacturers of atomic submarines), and celestial mechanics (financed by military and other institutions dealing with missiles, such as NASA)."
The article https://www.johndcook.com/non_central_chi_square.pdf sounds interesting:
John D. Cook Upper bounds on non-central chi-squared tails and truncated normal moments (2010). UT MD Anderson Cancer Center Department of Biostatistics Working Paper Series. Working Paper 62.
Abstract. We show that moments of the truncated normal distribution provide upper bounds on the tails of the non-central chi-squared distribution, then develop upper bounds for the former.
Computer codes produced and supported by the RLE Computational Prototyping Group.
Includes FASTCAP, a multipole-accelerated capacitance extraction program,
FastImp
The c++ program FastImp is a wideband impedance extraction program for 3D geometries. It could perform Magneto-Quasi-Static (MQS), Electro-Magneto-Quasi-Static (EMQS) and fullwave analysis of complicated3D structures from zero frequency to at least tens of Giga Hertz. These 3D structures are commonly seen in interconnects and packages of VLSI circuits.
FastHenry
This is a multipole-accelerated inductance analysis program.
The Cosmic Pi project aims to build the world's largest open source distributed cosmic ray telescope. You can be a part of the project, by becoming a Cosmic Pixel!
Converting color temperature (Kelvin) to RGB.
The algorithm provides a high-quality approximation, but it’s not accurate enough for serious scientific use. It’s designed primarily for photo manipulation – so don’t try and use it for astronomy or medical imaging.