93 research outputs found
Primordial Nucleosynthesis for the New Cosmology: Determining Uncertainties and Examining Concordance
Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have
a long history together in the standard cosmology. The general concordance
between the predicted and observed light element abundances provides a direct
probe of the universal baryon density. Recent CMB anisotropy measurements,
particularly the observations performed by the WMAP satellite, examine this
concordance by independently measuring the cosmic baryon density. Key to this
test of concordance is a quantitative understanding of the uncertainties in the
BBN light element abundance predictions. These uncertainties are dominated by
systematic errors in nuclear cross sections. We critically analyze the cross
section data, producing representations that describe this data and its
uncertainties, taking into account the correlations among data, and explicitly
treating the systematic errors between data sets. Using these updated nuclear
inputs, we compute the new BBN abundance predictions, and quantitatively
examine their concordance with observations. Depending on what deuterium
observations are adopted, one gets the following constraints on the baryon
density: OmegaBh^2=0.0229\pm0.0013 or OmegaBh^2 = 0.0216^{+0.0020}_{-0.0021} at
68% confidence, fixing N_{\nu,eff}=3.0. Concerns over systematics in helium and
lithium observations limit the confidence constraints based on this data
provide. With new nuclear cross section data, light element abundance
observations and the ever increasing resolution of the CMB anisotropy, tighter
constraints can be placed on nuclear and particle astrophysics. ABRIDGEDComment: 54 pages, 20 figures, 5 tables v2: reflects PRD version minor changes
to text and reference
Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4
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Thermostat related behavior and internal temperatures based on measured data in residences
Building interior temperature is one of the major driving forces of energy use. Steady-state heat transfer for a building is a function of the temperature difference between inside and outside air, along with the conductance of the building shell. Changes of only a few degrees in interior temperatures can significantly affect energy use in buildings. This report examines the internal temperatures collected from a large set of residences in the Pacific Northwest for the Bonneville Power Administration (Bonneville) by Pacific Northwest Laboratory (PNL). Three large programs sponsored by Bonneville now provide a large dataset. the Residential Standards Demonstration Program (RSDP) measured the interior temperatures of about 800 buildings at approximate weekly intervals. About 300 homes were end-use metered and data were collected at 15-min intervals in the Hood River Conservation Project (HRCP) in Hood River, Oregon. The End-Use Load and Consumer Assessment Program (ELCAP) measured interior temperatures in about 400 buildings, including a subset of the RSDP buildings. Accurate thermostat set points and/or schedules are needed in simulation models to obtain reasonable estimates of energy usage. Simpler simulations often presume a constant thermostat set point. More complex simulations assume interior temperature set points, which often include temperature setbacks. 1 ref., 22 figs., 5 tabs
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