Sonic properties of spider silks are measured independent of the web using laser vibrometry and ballistic impact providing insights into Nature's design of functionalized high-performance materials. Through comparison to cocoon silk and other industrial fibers, we find that major ampullate silk has the largest wavespeed range of any known material.

We analyze the impact of loss in lattices of coupled optical waveguides and find that, in such a case, the hopping between adjacent waveguides is necessarily complex. This results not only in a transition of the light spreading from ballistic to diffusive, but also in a new kind of diffraction that is caused by loss dispersion. We prove our theoretical results with experimental observations.

Ballistic simulation of the spray sprinkler for self-propelled irrigation machines requires the incorporation of the effect of the jet impact with the deflecting plate. The kinetic energy losses produced by the jet impact with the spray plate were experimentally characterized for different nozzle sizes and two working pressures for fixed spray plate sprinklers (FSPS). A technique of low speed p...

an internal ballistics model has been developed for performance prediction of a solid propellant rocket motor. inthis model a 1-d unsteady euler equation with source terms is considered. the flow is assumed as a non-reacting mixture of perfect gases with space and time varying thermo physical properties. the governing equations in the combustion chamber are solved numerically by using the stege...

Aaron Karp is Senior Faculty Associate with the Graduate Programs in International Studies at Old Dominion University in Norfolk, Virginia. He is the author of Ballistic Missile Proliferation (Oxford University Press, 1996) and numerous articles that have appeared in such journals as International Security, Survival, and International Studies Quarterly. LESSONS OF IRANIAN MISSILE PROGRAMS FOR U...

The ballistic perforation resistance of 50 mm thick concrete slabs impacted by 20 diameter ogive-nose steel projectiles is investigated experimentally and numerically. Three commercially produced concretes with nominal unconfined compressive strengths 35, 75 110 MPa were used to cast material test specimens slabs. After curing, impact tests carried out determine the limit curve velocity for eac...