7,051 research outputs found
Comparison of Preseason and In-Season Practice and Game Loads in National Collegiate Athletic Association Division i Football Players
Cosmology on a Mesh
An adaptive multi grid approach to simulating the formation of structure from
collisionless dark matter is described. MLAPM (Multi-Level Adaptive Particle
Mesh) is one of the most efficient serial codes available on the cosmological
'market' today. As part of Swinburne University's role in the development of
the Square Kilometer Array, we are implementing hydrodynamics, feedback, and
radiative transfer within the MLAPM adaptive mesh, in order to simulate
baryonic processes relevant to the interstellar and intergalactic media at high
redshift. We will outline our progress to date in applying the existing MLAPM
to a study of the decay of satellite galaxies within massive host potentials.Comment: 3 pages, 2 figures, to appear in the proceedings of "The IGM/Galaxy
Connection - The Distribution of Baryons at z=0", ed. M. Putman & J.
Rosenber
Half-life of the electron-capture decay of 97Ru: Precision measurement shows no temperature dependence
We have measured the half-life of the electron-capture (ec) decay of 97Ru in
a metallic environment, both at low temperature (19K), and also at room
temperature. We find the half-lives at both temperatures to be the same within
0.1%. This demonstrates that a recent claim that the ec decay half-life for 7Be
changes by $0.9% +/- 0.2% under similar circumstances certainly cannot be
generalized to other ec decays. Our results for the half-life of 97Ru,
2.8370(14)d at room temperature and 2.8382(14)d at 19K, are consistent with,
but much more precise than, previous room-temperature measurements. In
addition, we have also measured the half-lives of the beta-emitters 103Ru and
105Rh at both temperatures, and found them also to be unchanged.Comment: 6 pages, 6 figure
Assessing the Safety and Reliability of Autonomous Vehicles from Road Testing
There is an urgent societal need to assess whether
autonomous vehicles (AVs) are safe enough. From published
quantitative safety and reliability assessments of AVs, we know
that, given the goal of predicting very low rates of accidents,
road testing alone requires infeasible numbers of miles to
be driven. However, previous analyses do not consider any
knowledge prior to road testing – knowledge which could bring
substantial advantages if the AV design allows strong expectations
of safety before road testing. We present the advantages of a new
variant of Conservative Bayesian Inference (CBI), which uses
prior knowledge while avoiding optimistic biases. We then study
the trend of disengagements (take-overs by human drivers) by
applying Software Reliability Growth Models (SRGMs) to data
from Waymo’s public road testing over 51 months, in view of the
practice of software updates during this testing. Our approach is
to not trust any specific SRGM, but to assess forecast accuracy
and then improve forecasts. We show that, coupled with accuracy
assessment and recalibration techniques, SRGMs could be a
valuable test planning aid
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