3,113 research outputs found
Scaling of data communications for an advanced supercomputer network
The goal of NASA's Numerical Aerodynamic Simulation (NAS) Program is to provide a powerful computational environment for advanced research and development in aeronautics and related disciplines. The present NAS system consists of a Cray 2 supercomputer connected by a data network to a large mass storage system, to sophisticated local graphics workstations and by remote communication to researchers throughout the United States. The program plan is to continue acquiring the most powerful supercomputers as they become available. The implications of a projected 20-fold increase in processing power on the data communications requirements are described
Preparing Teacher Candidates to Meet the Needs of English Language Learners: The TELLs Certificate
A report on the development and implementation of the Teaching English Language Learners (TELLs) certificate program at Miami University, in Oxford Ohio
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Flashing Slurry Releases
The Hanford K Basin Closure Project involves the retrieval, transfer and processing of radioactive contaminated slurries containing partially corroded spent nuclear fuel from the K Basin spent fuel pools. The spent fuel is primarily metallic fuel from the operation of the Hanford reactors. The Sludge Treatment Project is being designed to treat and package this material in preparation for ultimate disposal. The processing of the contaminated slurries includes further corrosion of the remaining uncorroded uranium metal in a large heated vessel to form a more stable metal oxide for packaging and storage
Fluid Coexistence close to Criticality: Scaling Algorithms for Precise Simulation
A novel algorithm is presented that yields precise estimates of coexisting
liquid and gas densities, , from grand canonical Monte Carlo
simulations of model fluids near criticality. The algorithm utilizes data for
the isothermal minima of the moment ratio in boxes, where
. When the minima, , tend to zero while their locations, , approach and . Finite-size scaling
relates the ratio {\boldmath } {\em universally} to
, where
is the desired width of the
coexistence curve. Utilizing the exact limiting form, the
corresponding scaling function can be generated in recursive steps by fitting
overlapping data for three or more box sizes, , , , .
Starting at a sufficiently far below and suitably
choosing intervals 0 yields
and precisely locates
Enhancing anaerobic digestion of food waste through Biochemical Methane Potential 1 Assays at different substrate: inoculum ratios
Food waste has a high energy potential that can be converted into useful energy in the form of methane via anaerobic digestion. Biochemical Methane Potential assays (BMPs) were conducted to quantify the impacts on methane production of different ratios of food waste. Anaerobic digester sludge (ADS) was used as the inoculum, and BMPs were performed at food waste:inoculum ratios of 0.42, 1.42, and 3.0 g chemical oxygen demand/g volatile solids (VS). The 1.42 ratio had the highest CH4-COD recovery: 90% of the initial total chemical oxygen demand (TCOD) was from food waste, followed by ratios 0.42 and 3.0 at 69% and 57%, respectively. Addition of food waste above 0.42 caused a lag time for CH4 production that increased with higher ratios, which highlighted the negative impacts of overloading with food waste. The Gompertz equation was able to represent the results well, and it gave lag times of 0, 3.6 and 30 days and maximum methane productions of 370, 910, and 1950 mL for ratios 0.42, 1.42 and 3.0, respectively. While ratio 3.0 endured a long lag phase and low VSS destruction, ratio 1.42 achieved satisfactory results for all performance criteria. These results provide practical guidance on food-waste-to-inoculum ratios that can lead to optimizing methanogenic yield
Acceptability and effectiveness of opportunistic referral of smokers to telephone cessation advice from a nurse: a randomised trial in Australian general practice
<p>Abstract</p> <p>Background</p> <p>GPs often lack time to provide intensive cessation advice for patients who smoke. This study aimed to determine the effectiveness of opportunistic referral of smokers by their GP for telephone cessation counselling by a trained nurse.</p> <p>Methods</p> <p>Adult smokers (n = 318) attending 30 GPs in South Western Sydney, Australia were randomly allocated to usual care or referral to a telephone-based program comprising assessment and stage-based behavioural advice, written information and follow-up delivered by a nurse. Self-reported point prevalence abstinence at six and 12 months was compared between groups. Characteristics of patients who accepted and completed the intervention were investigated.</p> <p>Results</p> <p>Of 169 smokers randomised to the intervention, 76 (45%) consented to referral. Compared with smokers in 'pre-contemplation', those further along the stage-of-change continuum were significantly more likely to consent (p = 0.003). Those further along the continuum also were significantly more likely to complete all four calls of the intervention (OR 2.6, 95% CI: 0.8â8.1 and OR 8.6, 95% CI: 1.7â44.4 for 'contemplation' and 'preparation' respectively). At six months, there was no significant difference between groups in point prevalence abstinence (intention to treat) (9% versus 8%, p = 0.7). There was no evidence of differential intervention effectiveness by baseline stage-of-change (p = 0.6) or patient sex (p = 0.5). At 12 months, point prevalence abstinence in the intervention and control groups was 8% and 6% respectively (p = 0.6).</p> <p>Conclusion</p> <p>Acceptance of opportunistic referral for nurse delivered telephone cessation advice was low. This trial did not demonstrate improved quit rates following the intervention. Future research efforts might better focus support for those patients who are motivated to quit.</p> <p>Australian Clinical Trials Registry number</p> <p>ACTRN012607000091404</p
Detection of Anisotropies in the Gravitational-Wave Stochastic Background
By correlating the signals from a pair of gravitational-wave detectors, one
can undertake sensitive searches for a stochastic background of gravitational
radiation. If the stochastic background is anisotropic, then this correlated
signal varies harmonically with the earth's rotation. We calculate how the
harmonics of this varying signal are related to the multipole moments which
characterize the anisotropy, and give a formula for the signal-to-noise ratio
of a given harmonic. The specific case of the two LIGO (Laser Interferometric
Gravitational Observatory) detectors, which will begin operation around the
year 2000, is analyzed in detail. We consider two possible examples of
anisotropy. If the gravitational-wave stochastic background contains a dipole
intensity anisotropy whose origin (like that of the Cosmic Background
Radiation) is motion of our local system, then that anisotropy will be
observable by the advanced LIGO detector (with 90% confidence in one year of
observation) if \Omega_{gw} > 5.3 \times 10^{-8} h_{100}^{-2}. We also study
the signal produced by stochastic sources distributed in the same way as the
luminous matter in the galactic disk, and in the same way as the galactic halo.
The anisotropy due to sources distributed as the galactic disk or as the
galactic halo will be observable by the advanced LIGO detector (with 90%
confidence in one year of observation) if \Omega_{gw} > 1.8 \times 10^{-10}
h_{100}^{-2} or \Omega_{gw} > 6.7 \times 10^{-8} h_{100}^{-2}, respectively.Comment: 25 pages, Latex with RevTeX and epsfig, now includes S/N ratio
calculations, expected response from anisotropy due to local motion & sources
in galax
BCS 100 Module 3: Northern Environments
The landscapes of the Circumpolar North have been shaped by the interplay of physical, chemical and biological processes operating over many millennia or many millions of years.
Many of the physical features and processes found in the Circumpolar North are unique to this part of the earth. The flora and fauna of the northern regions are unique because the environments they inhabit are extreme and finely balanced.
This module provides a brief introduction to the physical and biological features and processes of the Arctic and Subarctic regions and highlights the significant factors that influence those features and processes
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