Fractal space frames and metamaterials for high mechanical efficiency

A solid slender beam of length $L$, made from a material of Young's modulus $Y$ and subject to a gentle compressive force $F$, requires a volume of material proportional to $L^{3}f^{1/2}$ [where $f\equiv F/(YL^{2})\ll 1$] in order to be stable against Euler buckling. By constructing a hierarchical space frame, we are able to systematically change the scaling of required material with $f$ so that it is proportional to $L^{3}f^{(G+1)/(G+2)}$, through changing the number of hierarchical levels $G$ present in the structure. Based on simple choices for the geometry of the space frames, we provide expressions specifying in detail the optimal structures (in this class) for different values of the loading parameter $f$. These structures may then be used to create effective materials which are elastically isotropic and have the combination of low density and high crush strength. Such a material could be used to make light-weight components of arbitrary shape.Comment: 6 pages, 4 figure

Searching for binary coalescences with inspiral templates: Detection and parameter estimation

There has been remarkable progress in numerical relativity recently. This has led to the generation of gravitational waveform signals covering what has been traditionally termed the three phases of the coalescence of a compact binary - the inspiral, merger and ringdown. In this paper, we examine the usefulness of inspiral only templates for both detection and parameter estimation of the full coalescence waveforms generated by numerical relativity simulations. To this end, we deploy as search templates waveforms based on the effective one-body waveforms terminated at the light-ring as well as standard post-Newtonian waveforms. We find that both of these are good for detection of signals. Parameter estimation is good at low masses, but degrades as the mass of the binary system increases.Comment: 14 pages, submitted to proceedings of the NRDA08 meeting, Syracuse, Aug. 11-14, 200

Senator Farr Reports, 1964-08-04

Interview with Cletus Fitzharris, Superintendent of Soledad Correctional Facility, and Lawrence Wilson, Warden of San Quentin, conducted while on a campout at Big Sur. Topics covered include California\u27s indeterminate sentence law, the inmate population at San Quentin, capital punishment, and prisoner rehabilitation.https://digitalcommons.csumb.edu/fredfarr_broadcasts/1010/thumbnail.jp

Fred Farr Is Our Friend, Campaign Poster

Poster promoting Fred Farr\u27s campaign for California State Assembly. Features a headshot of Farr in a button-up shirt, with his necktie over his shoulder. Poster text: Fred Farr is our friend. Return him to Sacramento June 17th. Fred Farr has the experience. Fred Farr can be effective.https://digitalcommons.csumb.edu/fredfarr_campaign/1003/thumbnail.jp