6,382 research outputs found
Conceptual design of thermal energy storage systems for near term electric utility applications. Volume 1: Screening of concepts
Over forty thermal energy storage (TES) concepts gathered from the literature and personal contacts were studied for their suitability for the electric utility application of storing energy off-peak discharge during peak hours. Twelve selections were derived from the concepts for screening; they used as storage media high temperature water (HTW), hot oil, molten salts, and packed beds of solids such as rock. HTW required pressure containment by prestressed cast-iron or concrete vessels, or lined underground cavities. Both steam generation from storage and feedwater heating from storage were studied. Four choices were made for further study during the project. Economic comparison by electric utility standard cost practices, and near-term availability (low technical risk) were principal criteria but suitability for utility use, conservation potential, and environmental hazards were considered
Conceptual design of thermal energy storage systems for near term electric utility applications. Volume 2: Appendices - screening of concepts
Volume 2 of this 2 volume report is represented. This volume contains three appendices: (1) bibliography and cross references; (2) taxonomy - proponents and sources; and (3) concept definitions
Charge injection instability in perfect insulators
We show that in a macroscopic perfect insulator, charge injection at a
field-enhancing defect is associated with an instability of the insulating
state or with bistability of the insulating and the charged state. The effect
of a nonlinear carrier mobility is emphasized. The formation of the charged
state is governed by two different processes with clearly separated time
scales. First, due to a fast growth of a charge-injection mode, a localized
charge cloud forms near the injecting defect (or contact). Charge injection
stops when the field enhancement is screened below criticality. Secondly, the
charge slowly redistributes in the bulk. The linear instability mechanism and
the final charged steady state are discussed for a simple model and for
cylindrical and spherical geometries. The theory explains an experimentally
observed increase of the critical electric field with decreasing size of the
injecting contact. Numerical results are presented for dc and ac biased
insulators.Comment: Revtex, 7pages, 4 ps figure
Investigation, Development, and Evaluation of Performance Proving for Fault-tolerant Computers
A number of methodologies for verifying systems and computer based tools that assist users in verifying their systems were developed. These tools were applied to verify in part the SIFT ultrareliable aircraft computer. Topics covered included: STP theorem prover; design verification of SIFT; high level language code verification; assembly language level verification; numerical algorithm verification; verification of flight control programs; and verification of hardware logic
Thyroid hormones correlate with resting metabolic rate, not daily energy expenditure, in two charadriiform seabirds
K. Woo, M. Le Vaillant, T. van Nus, and especially A. Wesphal, J. Schultner and I. Dorresteijn, assisted with field work, often under unpleasant conditions. K. Wauthier was instrumental in wrestling the gamma counter into submission. P. Redman and C. Hambly conducted the isotopic analyses. K. Scott and K. Campbell provided the FoxBox. K.H.E. benefited from a Natural Sciences and Engineering Research Council (NSERC) Vanier Scholarship, Association of Canadian Universities for Northern Studies Garfield Weston Northern Studies Award and the Arctic Institute of North America Jennifer Robinson Scholarship. Research support came from Bird Studies Canada/Society of Canadian Ornithologists James Baillie Award, Animal Behavior Society Research Grant, American Ornithologists’ Union Research Grant, Frank Chapman Research Grant, the Waterbird Society Nisbet Grant and NSERC Discovery Grants to J.F.H. and W.G.A. Any use of trade names is for descriptive purposes only and does not imply endorsement by the US Government.Peer reviewedPublisher PD
Airborne multiwavelength High Spectral Resolution Lidar (HSRL-2) observations during TCAP 2012 : Vertical profiles of optical and microphysical properties of a smoke/urban haze plume over the northeastern coast of the US
© Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License.We present measurements acquired by the world's first airborne 3 backscatter (β) + 2 extinction (α) High Spectral Resolution Lidar (HSRL-2). HSRL-2 measures particle backscatter coefficients at 355, 532, and 1064 nm, and particle extinction coefficients at 355 and 532 nm. The instrument has been developed by the NASA Langley Research Center. The instrument was operated during Phase 1 of the Department of Energy (DOE) Two-Column Aerosol Project (TCAP) in July 2012. We observed pollution outflow from the northeastern coast of the US out over the western Atlantic Ocean. Lidar ratios were 50-60 sr at 355 nm and 60-70 sr at 532 nm. Extinction-related Ångström exponents were on average 1.2-1.7, indicating comparably small particles. Our novel automated, unsupervised data inversion algorithm retrieved particle effective radii of approximately 0.2 μm, which is in agreement with the large Ångström exponents. We find good agreement with particle size parameters obtained from coincident in situ measurements carried out with the DOE Gulfstream-1 aircraft.Peer reviewedFinal Published versio
Chromosome composition in an F2 hexaploid x durum cross analysed by DArT markers and MCFISH
A major constraint to tetraploid durum wheat production in Australia is widespread susceptibility to crown rot, due to infection by Fusarium pseudograminearum
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