This set of Matlab scripts calculates the response of a single-degree-of-freedom system to an acceleration power spectral density base input: sdof_ran.zip The power spectral density may vary arbitrarily with frequency. The main script is: sdof_ran.m The user must specify the natural frequency and damping ratio. The… Read more
Mark 9 [38] And John answered him, saying, Master, we saw one casting out devils in thy name, and he followeth not us: and we forbad him, because he followeth not us. [39] But Jesus said, Forbid him not: for there is no man which… Read more
The software in the zip file was updated on December 21, 2012. A time history consisting of a series of damped sinusoids can be synthesized to satsify a shock response spectrum (SRS). A Matlab script for this is given in: damped_sine_syn.zip. The main script is: … Read more
The following Matlab files are given at: psd_syn_revD.zip psd_syn.m is the main Matlab script. The remaining scripts in the zip file are supporting functions. It synthesizes an acceleration time history to satisfy a power spectral density function. It also calculates the corresponding velocity and displacement… Read more
One of the first references to Zion in the Bible is: Nevertheless David took the strong hold of Zion: the same is the city of David. (2 Samuel 5:7). This scripture refers to a military battle in which David captured a fortress on Mount Zion… Read more
Here are some edited notes given to me by a colleague who is writing software programs to import Nastran data into Matlab. DMAP DMAP (Direct Matrix Abstraction Programming) is the language running under the hood in the various nastran solution sequences. All the math that happens… Read more
I will be presenting a 3-hour tutorial session at the 83rd Shock and Vibration Symposium in New Orleans, on November 4, 2012. My session is called “Shock Response Spectra & Time History Synthesis.” Students will receive basic instruction in calculating shock response spectra for time… Read more
The Lord doesn’t care at all if we spend our days working in marble halls or stable stalls. He knows where we are, no matter how humble our circumstances. He will use—in His own way and for His holy purposes—those who incline their hearts to… Read more
Pyrotechnic devices such as linear shaped charge and frangible joints are used for stage and fairing separation in launch vehicles. These devices generate high-frequency mechanical shock energy. Avionics components mounted in the vehicle must be designed and tested to withstand this shock energy. Thus, ground… Read more
The Apostle Paul taught: [7] For we walk by faith, not by sight. 2 Corinthians 5 * * * We walk by faith, and not by sight; no gracious words we hear from him who spoke as none e’er spoke; but we believe him near.… Read more