Magnetic suspension actuator concepts and applications

The fundamental aspect which makes magnetic suspension systems possible is the magnetic phenomena by which significant forces can be generated. Each of these force-producing phenomena has unique characteristics and is implementable in a unique fashion, such that each performs the magnetic suspension task differently than the others. A practical overview of the force-producing concepts, their unique characteristics, and their typical methods of application is provided

Employers Steal Billions from Workers' Paychecks Each Year

This paper finds that employers steal billions of dollars from American workers' paychecks each year, causing harm for working families, taxpayers, and the U.S. economy.While wage theft is difficult to measure and can occur in many forms, this report assesses one straightforward, identifiable type of wage theft: workers being paid less than the minimum wage. Using Current Population Survey data, the authors analyze minimum wage violations in the 10 largest U.S. states, finding that nearly one fifth of low-wage workers in these states are being cheated by their employers

Remittances and Children's Capabilities: New Evidence from Kyrgyzstan, 2005-2008

The Kyrgyz Republic is one of the largest recipients of international remittances in the world; from a Balance of Payments measure of remittances, it ranked tenth in the world in 2008 in the ratio of remittances to GDP, a rapid increase from 30th place in 2004.Remittances can be used to maintain the household's standard of living by providing income to families with unemployed and underemployed adult members. Remittances can also be used to promote investment not only in businesses and communities but also in people. In this paper, we examine the role that remittances have played in the Kyrgyz Republic in promoting investments in children. Based on the capabilities approach to well-being initiated by Sen (2010), we look at the impact of remittances and domestic transfer payments primarily from internal migration on children's education and health. Our outcomes include enrollment in school and preschool, expenditures, stunting and wasting of preschool children, and health habits of older children. We use unique panel data from the Kyrgyz Republic for 2005-2008 and thus control for some of the biases inherent in cross-sectional studies of remittances and family outcomes. We find that overall remittances and domestic transfers have not promoted investments in the human capital of children. Specifically, preschool enrollments were higher in the urban north but secondary school enrollments were lower in other regions in remittance receiving households; expenditures were also negatively affected in the south and the mountain areas. These negative enrollment results were larger for girls than for boys. We also found evidence of stunting and wasting among young children and worse health habits among boys in remittance or transfer receiving households. In the long run, Kyrgyzstan needs human capital development for growth; our results suggest that remittances are not providing the boost needed in human capital to promote development in the future.Children’s education and health, Remittances, Kyrgyzstan, Central Asia

COLD-SAT: A technology satellite for cryogenic experimentation

NASA-Lewis (LeRC) is involved in the development and validation of analytical models which describe the fluid dynamic and thermodynamic processes associated with the storage, acquisition and transfer of subcritical cryogenic fluids in low gravity. Four concurrent studies, including one in-house at LeRC, are underway to determine the feasibility of performing model validation experiments aboard a free-flying spacecraft (S/C) called Cryogenic On-Orbit Liquid Depot-Storage, Acquisition and Transfer (COLD-SAT), using liquid hydrogen as the cryogen. The technology requirements for the experiments are described along with the initial LeRC concepts for the S/C and an experiment subsystem comprising of cryogenic tankage (a supply dewar and three receiver tanks), gas pressurization bottles (both helium and autogenous hydrogen), their associated plumbing, and instrumentation for data collection. Experiments were categorized into enabling/high priority Class 1 technologies and component/system Class 2 demonstrations. As initially envisioned by LeRC, COLD-SAT would have had a 1997 launch aboard a Delta-2 for a 6 month active lifetime in a 925 km orbit with a pseudo-inertial attitude

Lithium and potassium heat pipes for thermionic converters

A prototypic heat pipe system for an out-of-core thermionic reactor was built and tested. The emitter of the concentric thermionic converter consists of the condenser of a tungsten heat pipe utilizing a lithium working fluid. The evaporator section of the emitter heat pipe is radiation heated to simulate the thermal input from the nuclear reactor. The emitter heat pipe thermal transport is matched to the thermionic converter input requirement. The collector heat pipe of niobium, 1% zirconium alloy uses potassium as the working fluid. The thermionic collector is coupled to the heat pipe by a tapered conical joint designed to minimize the temperature drop. The collector heat flux matches the design requirements of the thermionic converter

Phase coherence length and quantum interference patterns at step edges

The accepted approximation used to describe quantum interference patterns at steps is shown to be incorrect. As a result, electron lifetimes determined using it are in error by a factor 2.Comment: 3 pages, 1 figur