938 research outputs found
Information support of problems of electric power systems control
Розглянуто особливості створення систем інформаційного забезпечення в електроенергетиці. Проведено аналіз вимог ENTSO-E, що стосуються моніторингу режимних параметрів. Досліджено проблему моніторингу низькочастотних коливань режимних параметрів при об’єднанні енергосистем на паралельну роботу. Визначені часові та ієрархічні обмеження задач керування. Представлено систему збору та обробки інформації, що реєструється комплексами «Регіна-Ч» на об’єктах ОЕС України. Наведені приклади реалізації.Features of information support systems creation in power engineering are considered. The analysis of requirements ENTSO-E, concerning monitoring of operating parameters is carried out. It is investigated a problem of monitoring of low-frequency oscillation of operating parameters at association of power systems for parallel operation. Time and hierarchical limitations of control problems are defined. System of gathering and processing of the information registered on objects of Ukrainian IPS by complexes "Regina-F" are presented. Examples are resulted.Рассмотрены особенности создания систем информационного обеспечения в электроэнергетике. Проведен анализ требований ENTSO-E, касающихся мониторинга режимных параметров. Исследовано проблему мониторинга низкочастотных колебаний режимных параметров при объединении энергосистем на параллельную работу. Определены временные и иерархические ограничения задач управления. Представлено систему сбора и обработки информации регистрируемой комплексами «Регина-Ч» на объектах ОЭС Украины. Приведены примеры
Transverse Enhancement Model and MiniBooNE Charge Current Quasi-Elastic Neutrino Scattering Data
Recently proposed Transverse Enhancement Model of nuclear effects in Charge
Current Quasi-Elastic neutrino scattering [A. Bodek, H. S. Budd, and M. E.
Christy, Eur. Phys. J. C{\bf 71} (2011) 1726] is confronted with the MiniBooNE
high statistics experimental data. It is shown that the {\it effective} large
axial mass model leads to better agreement with the data.Comment: 4 pages, 6 figure
Neutrino Quasielastic Scattering on Nuclear Targets: Parametrizing Transverse Enhancement (Meson Exchange Currents)
We present a parametrization of the observed enhancement in the transverse
electron quasielastic (QE) response function for nucleons bound in carbon as a
function of the square of the four momentum transfer () in terms of a
correction to the magnetic form factors of bound nucleons. The parametrization
should also be applicable to the transverse cross section in neutrino
scattering. If the transverse enhancement originates from meson exchange
currents (MEC), then it is theoretically expected that any enhancement in the
longitudinal or axial contributions is small. We present the predictions of the
"Transverse Enhancement" model (which is based on electron scattering data
only) for the differential and total QE cross sections
for nucleons bound in carbon. The dependence of the transverse
enhancement is observed to resolve much of the long standing discrepancy in the
QE total cross sections and differential distributions between low energy and
high energy neutrino experiments on nuclear targets.Comment: Revised Version- July 21, 2011: 17 pages, 20 Figures. To be published
in Eur. Phys. J.
Cosmic muon flux at shallow depths underground
We consider the cosmic muon background for the installations located at
shallow depths. We suggest a relatively simple formula for the sea-level muon
spectrum, which allows calculate dependencies of the vertical muon intensity
and integral muon flux density on overburden. Muon flux dependency on the
zenith angle at overburden of 10 to 100 meters of standard rock shows that muon
angular distribution practically does not change in this interval. We present
muon angular distributions for three typical apparatus locations in
measurements on the surface and at shallow depths. It is shown that for such
installations the active shielding "umbrella" should overlap a zenith angle of
\theta ~ 80^o to remove the cosmic muon background.Comment: 9 pages, 6 figures, submitted to Phys.Atom.Nuc
Comparing and contrasting the and solutions to the atmospheric neutrino problem with SuperKamiokande data
The and solutions to the
atmospheric neutrino problem are compared with SuperKamiokande data. The
differences between these solutions due to matter effects in the Earth are
calculated for the ratio of -like to -like events and for up-down flux
asymmetries. These quantities are chosen because they are relatively
insensitive to theoretical uncertainties in the overall neutrino flux
normalisation and detection cross-sections and efficiencies. A
analysis using these quantities is performed yielding ranges which
are approximately given by and for
for the and solutions, respectively. Values of smaller than about
eV are disfavoured for the
solution, suggesting that future long baseline experiments should see a
positive signal if this scenario is the correct one.Comment: revtex, 22 pages, 12 figure
Atmospheric Muon Flux at Sea Level, Underground, and Underwater
The vertical sea-level muon spectrum at energies above 1 GeV and the
underground/underwater muon intensities at depths up to 18 km w.e. are
calculated. The results are particularly collated with a great body of the
ground-level, underground, and underwater muon data. In the hadron-cascade
calculations, the growth with energy of inelastic cross sections and pion,
kaon, and nucleon generation in pion-nucleus collisions are taken into account.
For evaluating the prompt muon contribution to the muon flux, we apply two
phenomenological approaches to the charm production problem: the recombination
quark-parton model and the quark-gluon string model. To solve the muon
transport equation at large depths of homogeneous medium, a semi-analytical
method is used. The simple fitting formulas describing our numerical results
are given. Our analysis shows that, at depths up to 6-7 km w. e., essentially
all underground data on the muon intensity correlate with each other and with
predicted depth-intensity relation for conventional muons to within 10%.
However, the high-energy sea-level data as well as the data at large depths are
contradictory and cannot be quantitatively decribed by a single nuclear-cascade
model.Comment: 47 pages, REVTeX, 15 EPS figures included; recent experimental data
and references added, typos correcte
Single neutral pion production by charged-current interactions on hydrocarbon at 3.6 GeV
Single neutral pion production via muon antineutrino charged-current
interactions in plastic scintillator (CH) is studied using the \minerva
detector exposed to the NuMI low-energy, wideband antineutrino beam at
Fermilab. Measurement of this process constrains models of neutral pion
production in nuclei, which is important because the neutral-current analog is
a background for appearance oscillation experiments. The
differential cross sections for momentum and production angle, for
events with a single observed and no charged pions, are presented and
compared to model predictions. These results comprise the first measurement of
the kinematics for this process.Comment: 6 pages, 5 figures, submitted to Physics Letters
- …