Peak wind speed anemometers /maxometer/ Final report, 26 Mar. 1969 - 25 May 1970

Fabrication and testing of peak wind speed recording devic

Frequency Shifts Inherent in the 6328 a Helium-neon Laser

Frequency shifts inherent in helium neon lase

Theory of the evolutionary minority game

We present a theory which describes a recently introduced model of an evolving, adaptive system in which agents compete to be in the minority. The agents themselves are able to evolve their strategies over time in an attempt to improve their performance. The present theory explicitly demonstrates the self-interaction, or so-called market impact, that agents in such systems experience

Design of an inert fluid injection system, phase 3 Final report

Research, development, and design of velocity trim system for third stage of Delta launch vehicl

The Increasing Diversity of America\u27s Youth

This brief documents how unfolding demographic forces have placed today’s children and youth at the forefront of America’s new racial and ethnic diversity. Authors Kenneth M. Johnson, Andrew Schaefer, Daniel T. Lichter, and Luke T. Rogers discuss how the rapidly changing racial and ethnic composition of the youth population has important implications for intergroup relations, ethnic identities, and electoral politics. They report that diversity is increasing among America’s youth because there are more minority children and fewer non-Hispanic white children. Minority births exceeded non-Hispanic white births for the first time in U.S. history in 2011 according to Census Bureau estimates. Both the declining number of non-Hispanic white women of prime child-bearing and growing numbers of minority women contributed to this change as did differential fertility rates. The largest gains in child diversity between 2000 and 2012 were in suburban and smaller metropolitan areas. Yet, child diversity is geographically uneven, with minimal diversity in some areas of the country and significant diversity in other areas. They conclude that natural population increase—particularly fertility rates—will continue to reshape the racial and ethnic mix of the country, and this change will be reflected first among the nation’s youngest residents

Theory of enhanced performance emerging in a sparsely-connected competitive population

We provide an analytic theory to explain Anghel et al.'s recent numerical finding whereby a maximum in the global performance emerges for a sparsely-connected competitive population [Phys. Rev. Lett. 92, 058701 (2004)]. We show that the effect originates in the highly-correlated dynamics of strategy choice, and can be significantly enhanced using a simple modification to the model.Comment: This revised version will appear in PRE as a Rapid Com

Spiral-grooved shaft seals substantially reduce leakage and wear

Rotating shaft seals used in space power systems have spiral grooves in one or both of the opposing seal faces. These grooves induce a pumping action which displaces the intervening fluid radially inward toward the shaft and counters the centrifugal forces which tend to displace the fluid outward

Adiabatic self-tuning in a silicon microdisk optical resonator

We demonstrate a method for adiabatically self-tuning a silicon microdisk resonator. This mechanism is not only able to sensitively probe the fast nonlinear cavity dynamics, but also provides various optical functionalities like pulse compression, shaping, and tunable time delay

An improved panel method for the solution of three-dimensional leading edge vortex flows Volume 2: User's guide and programmer's document

A computer program developed for solving the subsonic, three dimensional flow over wing-body configurations with leading edge vortex separation is presented. Instructions are given for the proper set up and input of a problem into the computer code. Program input formats and output are described, as well as the overlay structure of the program. The program is written in FORTRAN