We are not human beings having a spiritual experience; we are spiritual beings having a human experience. – Pierre Teilhard de Chardin (1881-1955) Quoted by: President Thomas S. Monson, BYU Devotional Be a Light to the World, November 1, 2011 * * * * *… Read more
“In our friendly neighbor city of St. Augustine, great flocks of sea gulls are starving amid plenty. Fishing is still good, but the gulls don’t know how to fish. For generations they have depended on the shrimp fleet to toss them scraps from the nets.… Read more
These are the generations of the heavens and of the earth when they were created, in the day that the Lord God made the earth and the heavens. Genesis 2:4 * * * In rabbinic conception, Adonai “Lord” represents the attribute of mercy, while Elohim… Read more
The punch file method may be used to extract the mass & stiffness matrices from Nastran models. The format is awkward since zero terms are not stored. Also the matrices are assumed to be symmetric, and the upper triangular portion above the diagonal is not… Read more
A sound file from the attack on the U.S. Embassy in Cuba has now been made available on the Internet. I did a spectral analysis of this file using my Matlab GUI scripts. The sound source is still unknown. The attacks have caused hearing, cognitive,… Read more
NASA SP-8072 Acoustics Loads Generate by the Propulsion System (Alternate SP-8072 link) The liftoff analysis has been added to the GUI package at: Vibrationdata Matlab GUI The function can be accessed via: >> vibrationdata > Miscellaneous Functions I > Acoustics Vibroacoustics & SEA > acoustics >… Read more
This post is a work-in-progress… Combined Ascent Loads for Launch Vehicle Analysis Equivalent Axial & Line Loads for Launch Vehicles Launch Vehicle and Spacecraft Primary Structure Response to High Frequency Shock and Vibration – Tom Irvine
Figure 1. Boeing 787 Aircraft Carbon fiber/epoxy laminates are widely used in aeronautic and aerospace structural components mainly because of their excellent specific mechanical properties. These laminates show mechanical properties similar or higher than the conventional metallic materials in terms of strength-to-weight and stiffness-to-weight ratios. The… Read more
Rolls Royce Engine Blade-off Test Video Link 1 Video Link 2 The engine blade-off test is performed to make sure that the engine can survive a fan. compressor or turbine blade breaking off within the engine, without fragments being ejected through the outside… Read more
The Lomb-Scargle Periodogram is a least-square method which is useful for calculating the Fourier transform of a time history with gaps or an uneven sampling rate. Reference Paper This function has been added to the vibrationdata GUI package Python script & Utility: lomb_scargle.py tompy.py -… Read more