44,239 research outputs found
Making automated computer program documentation a feature of total system design
It is pointed out that in large-scale computer software systems, program documents are too often fraught with errors, out of date, poorly written, and sometimes nonexistent in whole or in part. The means are described by which many of these typical system documentation problems were overcome in a large and dynamic software project. A systems approach was employed which encompassed such items as: (1) configuration management; (2) standards and conventions; (3) collection of program information into central data banks; (4) interaction among executive, compiler, central data banks, and configuration management; and (5) automatic documentation. A complete description of the overall system is given
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A Folk Tale of an Elderly Monk
Bstan 'dzin tells a folk tale in which a rabbit, a wolf, a magpie, and a pigeon cheat an elderly monkThis collection of 77 audio files focuses on weddings and weddings speeches but also contains: folk tales, folk songs, riddles, tongue twisters, and local history from Bang smad Village and Ri sne Village, Bang smad Township, Nyag rong CountyWorld Oral Literature Projec
Dissociative recombination measurements of HCl+ using an ion storage ring
We have measured dissociative recombination of HCl+ with electrons using a
merged beams configuration at the heavy-ion storage ring TSR located at the Max
Planck Institute for Nuclear Physics in Heidelberg, Germany. We present the
measured absolute merged beams recombination rate coefficient for collision
energies from 0 to 4.5 eV. We have also developed a new method for deriving the
cross section from the measurements. Our approach does not suffer from
approximations made by previously used methods. The cross section was
transformed to a plasma rate coefficient for the electron temperature range
from T=10 to 5000 K. We show that the previously used HCl+ DR data
underestimate the plasma rate coefficient by a factor of 1.5 at T=10 K and
overestimate it by a factor of 3.0 at T=300 K. We also find that the new data
may partly explain existing discrepancies between observed abundances of
chlorine-bearing molecules and their astrochemical models.Comment: Accepted for publication in ApJ (July 7, 2013
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
The effect of flooding on the exchange of the volatile C₂-compounds ethanol, acetaldehyde and acetic acid between leaves of Amazonian floodplain tree species and the atmosphere
The effect of root inundation on the leaf emissions of ethanol, acetaldehyde and acetic acid in relation to assimilation and transpiration was investigated with 2–3 years old tree seedlings of four Amazonian floodplain species by applying dynamic cuvette systems under greenhouse conditions. Emissions were monitored over a period of several days of inundation using a combination of Proton Transfer Reaction Mass Spectrometry (PTR-MS) and conventional techniques (HPLC, ion chromatography). Under non-flooded conditions, none of the species exhibited measurable emissions of any of the compounds, but rather low deposition of acetaldehyde and acetic acid was observed instead. Tree species specific variations in deposition velocities were largely due to variations in stomatal conductance. Flooding of the roots resulted in leaf emissions of ethanol and acetaldehyde by all species, while emissions of acetic acid were only observed from the species exhibiting the highest ethanol and acetaldehyde emission rates. All three compounds showed a similar diurnal emission profile, each displaying an emission burst in the morning, followed by a decline in the evening. This concurrent behavior supports the conclusion, that all three compounds emitted by the leaves are derived from ethanol produced in the roots by alcoholic fermentation, transported to the leaves with the transpiration stream and finally partly converted to acetaldehyde and acetic acid by enzymatic processes. Co-emissions and peaking in the early morning suggest that root ethanol, after transportation with the transpiration stream to the leaves and enzymatic oxidation to acetaldehyde and acetate, is the metabolic precursor for all compounds emitted, though we can not totally exclude other production pathways. Emission rates substantially varied among tree species, with maxima differing by up to two orders of magnitude (25–1700 nmol m−2 min−1 for ethanol and 5–500 nmol m−2 min−1 for acetaldehyde). Acetic acid emissions reached 12 nmol m−2 min−1. The observed differences in emission rates between the tree species are discussed with respect to their root adaptive strategies to tolerate long term flooding, providing an indirect line of evidence that the root ethanol production is a major factor determining the foliar emissions. Species which develop morphological root structures allowing for enhanced root aeration produced less ethanol and showed much lower emissions compared to species which lack gas transporting systems, and respond to flooding with substantially enhanced fermentation rates and a non-trivial loss of carbon to the atmosphere. The pronounced differences in the relative emissions of ethanol to acetaldehyde and acetic acid between the tree species indicate that not only the ethanol production in the roots but also the metabolic conversion in the leaf is an important factor determining the release of these compounds to the atmosphere
Absolute rate coefficients for photorecombination of berylliumlike and boronlike silicon ions
We report measured rate coefficients for electron-ion recombination for Si10+
forming Si9+ and for Si9+ forming Si8+, respectively. The measurements were
performed using the electron-ion merged-beams technique at a heavy-ion storage
ring. Electron-ion collision energies ranged from 0 to 50 eV for Si9+ and from
0 to 2000 eV for Si10+, thus, extending previous measurements for Si10+ [Orban
et al. 2010, Astrophys. J. 721, 1603] to much higher energies. Experimentally
derived rate coefficients for the recombination of Si9+ and Si10+ ions in a
plasma are presented along with simple parameterizations. These rate
coefficients are useful for the modeling of the charge balance of silicon in
photoionized plasmas (Si9+ and Si10+) and in collisionally ionized plasmas
(Si10+ only). In the corresponding temperature ranges, the experimentally
derived rate coefficients agree with the latest corresponding theoretical
results within the experimental uncertainties.Comment: 17 pages, 7 figures, 3 tables, 66 references, submitted to the J.
Phys. B special issue on atomic and molecular data for astrophysicist
BL-WoLF: A Framework For Loss-Bounded Learnability In Zero-Sum Games
We present BL-WoLF, a framework for learnability in repeated zero-sum games
where the cost of learning is measured by the losses the learning agent accrues
(rather than the number of rounds). The game is adversarially chosen from some
family that the learner knows. The opponent knows the game and the learner's
learning strategy. The learner tries to either not accrue losses, or to quickly
learn about the game so as to avoid future losses (this is consistent with the
Win or Learn Fast (WoLF) principle; BL stands for ``bounded loss''). Our
framework allows for both probabilistic and approximate learning. The resultant
notion of {\em BL-WoLF}-learnability can be applied to any class of games, and
allows us to measure the inherent disadvantage to a player that does not know
which game in the class it is in. We present {\em guaranteed
BL-WoLF-learnability} results for families of games with deterministic payoffs
and families of games with stochastic payoffs. We demonstrate that these
families are {\em guaranteed approximately BL-WoLF-learnable} with lower cost.
We then demonstrate families of games (both stochastic and deterministic) that
are not guaranteed BL-WoLF-learnable. We show that those families,
nevertheless, are {\em BL-WoLF-learnable}. To prove these results, we use a key
lemma which we derive
Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector
A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13 TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
Radiative rotational lifetimes and state-resolved relative detachment cross sections from photodetachment thermometry of molecular anions in a cryogenic storage ring
Photodetachment thermometry on a beam of OH in a cryogenic storage ring
cooled to below 10 K is carried out using two-dimensional, frequency and time
dependent photodetachment spectroscopy over 20 minutes of ion storage. In
equilibrium with the low-level blackbody field, we find an effective radiative
temperature near 15 K with about 90% of all ions in the rotational ground
state. We measure the J = 1 natural lifetime (about 193 s) and determine the
OH rotational transition dipole moment with 1.5% uncertainty. We also
measure rotationally dependent relative near-threshold photodetachment cross
sections for photodetachment thermometry.Comment: Manuscript LaTeX with 5 pages, 3 figures, and 1 table plus LaTeX
supplement with 12 pages, 3 figures and 3 tables. This article has been
accepted by Physical Review Letter
Observation of the Isospin-Violating Decay
Using data collected with the CLEO~II detector, we have observed the
isospin-violating decay . The decay rate for this mode,
relative to the dominant radiative decay, is found to be .Comment: 8 page uuencoded postscript file, also available through
http://w4.lns.cornell.edu/public/CLN
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