For the next 75 years, the Old-Age, Survivors, and Disability Insurance (OASDI) system is projected to be close to in balance, on average. For approximately the next 40 years, under current projections, the combined OASDI Trust Fund is expected to continually have excesses of income over outgo, creating a buildup that will peak in 2030 at about +12 1/2 trillion (roughly 23 percent of the gross ...

The first North American full scale post aerobic digester (PAD) is successfully operating at the Spokane County Regional Water Reclamation Facility (SCRWRF). The SCRWRF PAD has demonstrated ammonia removals of 90% or above without alkalinity or supplemental carbon addition. When operational controls were optimized for total inorganic nitrogen (TIN) removal, the SCRWRF PAD demonstrated effluent ...

We developed and applied a model-driven feedforward control approach to mitigate thermal-induced flaw formation in laser powder bed fusion (LPBF) additive manufacturing process. The key idea was avert heat buildup LPBF part before it is printed by adapting process parameters layer-by-layer based on insights from physics-based thermal simulation model. motivation being replace cumbersome empiric...

Laser powder-based directed energy deposition (DED-L) is increasingly being used in additive manufacturing (AM). As AM technology, DED-L must consider specific challenges. It achieve uniform volume growth over hundreds of layers and avoid heat buildup the deposited material. Herein, Ti–6Al–4V fabricated using an approach that addresses these challenges relevant terms transferability to DED–L ap...

An analytical expression for the difference in buildup time between two longitudinal modes in a passively Q -switched laser resonator is developed and compared with experimental laser data. The results support the following temporal criterion for single-frequency, passively Q -switched operation: The difference in buildup time between any two longitudinal modes of the laser resonator should be ...

We theoretically investigate the controlled dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. Three regimes of long-term dynamics are identified, including the buildup of a large difference in the Overhauser fields across the dots, the saturation of the nuclear polarization process associated with formation of so-called "dark states", and the el...

The effects of including incoherent (bound-electron) and coherent (Rayleigh) scattering in exposure buildup factor calculations for point isotropic gamma ray sources, penetrating a two-layer water-lead shield have been investigated in the gamma ray energy (E?) range of 40 keV to 3 MeV. Incoherent scattering decreases the values of these factors in both layers up to E? ~ 200 keV and the effect i...