8,360 research outputs found
Recent Results From CHORUS Charm Analysis
The CHORUS experiment was designed to search for
oscillation by detecting the decay topology of the in charged current
(CC) events. The detector was exposed to the Wide Band Neutrino
Beam of the CERN SPS during the years 1994-1997. About CC
events were collected in the nuclear emulsion target. Up to now, about 170,000
events have been located and analysed. The speed of the automated
emulsion scanning systems increases each year. With the present performance of
these systems, it has become possible to perform large volume scanning. All
tracks belonging to an interaction vertex can be recognized and measured
precisely. This technique is not only applied to the search for neutrino
oscillation but can also be used for the recognition of events where charmed
particles are produced. Results obtained from the analysis of a sub-sample of
the data on the production rate in CC interactions of neutral charmed
mesons () and charmed baryons () are presented. In addition a
new measurement of the branching ratio for the decays of charmed hadrons into
muons is given. Also measurements of topological branching ratios of and
are presented. Finally, a search for associated charm production is
discussed.Comment: 6 pages, 1 figure, to appear in the proceedings of the Conference:
XXXVIII Rencontres de Moriond: Electroweak Interactions and Unified Theories
Les Arcs, France, March 15-22, 200
Turbo-Aggregate: Breaking the Quadratic Aggregation Barrier in Secure Federated Learning
Federated learning is a distributed framework for training machine learning
models over the data residing at mobile devices, while protecting the privacy
of individual users. A major bottleneck in scaling federated learning to a
large number of users is the overhead of secure model aggregation across many
users. In particular, the overhead of the state-of-the-art protocols for secure
model aggregation grows quadratically with the number of users. In this paper,
we propose the first secure aggregation framework, named Turbo-Aggregate, that
in a network with users achieves a secure aggregation overhead of
, as opposed to , while tolerating up to a user dropout
rate of . Turbo-Aggregate employs a multi-group circular strategy for
efficient model aggregation, and leverages additive secret sharing and novel
coding techniques for injecting aggregation redundancy in order to handle user
dropouts while guaranteeing user privacy. We experimentally demonstrate that
Turbo-Aggregate achieves a total running time that grows almost linear in the
number of users, and provides up to speedup over the
state-of-the-art protocols with up to users. Our experiments also
demonstrate the impact of model size and bandwidth on the performance of
Turbo-Aggregate
production rate measurement in neutrino interactions and a limit on muon neutrino to tau neutrino oscillations
The CHORUS experiment was designed to search for \nu_\mu---> \nu_\tau oscillations. Recently, Phase I analysis has been completed and no \tau candidate is found. The second phase of the CHORUS analysis was recently started with new scanning systems. The big improvements in the scanning system and methods allow the CHORUS experiment to study also charm physics with large statistics. In this work, D^0 production rate in neutrino charged-current interactions has been evaluated using 122 D^0 candidates found in 8028 located \nu_\mu charged-current interactions in the collaboration, as; \sigma(\nu_mu N--> D^0\mu^-X)/sigma(\nu_mu N--> \mu^-X)= 1.998 \pm 0.223%. The achived precision of the production rate exceeds that of the previous experiments
OPERA neutrino oscillation results
The OPERA experiment was designed to perform the first detection of νμ → ντ neutrino oscillations in a direct appearance mode. We present the analysis results of the 2008–2009 statistics corresponding to 4.88 × 1019 p.o.t. In this sample, one ντ candidate event has been observed in the τ → h channel. The statistical significance of this observation is estimated to be 95%
Effect of feeding regime on fatty acid composition and conjugated linoleic acid content of perirenal, omental and tail fat in Akkaraman lambs
In this study, the effect of feeding regime on fatty acid composition including conjugated linoleic acid (CLA) of omental, perirenal and tail fat from Akkaraman lambs, the most widespread sheep breed in central Anatolia, was investigated. Forty-five suckling lambs, born in the same farm, were fed mainly maternal milk from birth to weaning and then the lambs were divided into three groups. One group (maternal milk-fed group) of the lambs was directly slaughtered after weaning. A second group (pasture group) was allowed to graze a natural pasture and slaughtered at three months after weaning. Third group (concentrate group) was fed concentrate ad-libitum together with 150 g/day alfalfa and slaughtered at three months after weaning. In all feeding regime, the predominant fatty acids were C 16:0 palmitic and C 18:0 stearic acid as saturated fatty acid (SFA), C 18:1ω9 oleic acid as monounsaturated fatty acid (MUFA) and C 18:2 ω6 linoleic acid as polyunsaturated fatty acid (PUFA). Omental, perirenal and tail fat of the pasture-fed lambs contained more total CLA, total ω3, ω3/ω6ratio compared with that of the concentrate-fed lambs. Moreover, omental, perirenal and tail fat of concentrate-fed lambs had higher ω6/ω3 ratio and this ratio was decreased by pasture feeding.Key words: Akkaraman lambs, pasture, suckling, concentrate, fatty acid composition, conjugated linoleic acid
Predicting Shear Capacity of RC Beams Strengthened with NSM FRP Using Neural Networks
This research aims to predict the shear capacity
of NSM FRP beams using the neural network method. The study investigates the key considerations and the necessary analysis for this prediction. NSM FRP beams are reinforced concrete beams that are strengthened with near-surface mounted (NSM) fiber-reinforced polymer (FRP) composites. Accurately predicting their shear capacity is important for ensuring their safety and reliability in real-world applications. The neural network method is a machine learning approach that is increasingly used in engineering analysis and design. The study explores how this method can be used to predict the shear capacity of NSM FRP beams and what factors should be taken into account in this analysis. The research also discusses the analytical approach required for this prediction, highlighting the necessary steps for obtaining accurate results. Overall, this study provides valuable insights into the use of the neural network method for predicting the shear capacity of NSM FRP beams. The findings can help inform future research and practical applications in the field of structural engineering, contributing to the development of safer and more reliable structures
Indentation of a free beam resting on an elastic substrate with an internal lengthscale
The plane strain problem of a slender and weightless beam-plate loaded by a transversal point force in unilateral contact with a couple stress elastic foundation is investigated. The study aims to explore the consequences of the material internal lengthscale on the contact mechanics. In particular, compatibility between the beam and the foundation surface demands that both displacement and rotation match along the contact line. To this aim, couple tractions are exchanged besides the traditional contact pressure until separation between the beam and the foundation occurs. The problem is formulated making use of the Green's functions for a point force and a point couple acting atop of a couple stress elastic half-plane. A pair of coupled integral equations is thus derived, that governs the distribution of contact pressure and couple tractions, with one of them being immediately solved to provide an explicit relation between the two unknowns. In this sense, we retrieve the concept of a mechanically equivalent action, as it is the case of the Kirchhoff shear for plates. The remaining integral equation sets a cubic eigenvalue problem, whose linear term accounts for the microstructure. Its numerical solution is sought by expanding the equivalent contact pressure in series of Chebyshev polynomials vanishing at the contact region ends points, namely the lift-off points, and then applying a collocation strategy. The contact length, the distributions of contact pressure and couple tractions under the beam and the shearing force and bending moment along the beam are then obtained as a function of the material characteristic length. Results clearly indicate that accounting for the material internal lengthscale is mainly realized through exchange of the couple tractions, in the lack of which results much resemble those of the classical solution. Specifically, greater contact lengths and a stronger focusing effect about the loading point are encountered, which become very significant when the contact length approaches the internal lengthscale
High precision determination of the -evolution of the Bjorken Sum
We present a significantly improved determination of the Bjorken Sum for
0.64.8 GeV using precise new and
data taken with the CLAS detector at Jefferson Lab. A higher-twist analysis of
the -dependence of the Bjorken Sum yields the twist-4 coefficient
. This leads to the color
polarizabilities and
. The strong force coupling is determined to be
\alpha_{s}^{\overline{\mbox{ MS}}}(M_{Z}^{2})=0.1124\pm0.0061, which has an
uncertainty a factor of 1.5 smaller than earlier estimates using polarized DIS
data. This improvement makes the comparison between extracted from
polarized DIS and other techniques a valuable test of QCD.Comment: Published in Phys. Rev. D. V1: 8 pages, 3 figures. V2: Updated
references; Included threshold matching in \alpha_s evolution. Corrected a
typo on the uncertainty for \Lambda_QCD. V3: Published versio
Non-cooperative joint replenishment under asymmetric information
Cataloged from PDF version of article.We consider jointly replenishing n ex-ante identical firms that operate under an EOQ like setting using a
non-cooperative game under asymmetric information. In this game, each firm, upon being privately
informed about its demand rate (or inventory cost rate), submits a private contribution to an intermediary
that specifies how much it is willing to pay for its replenishment per unit of time and the intermediary
determines the maximum feasible frequency for the joint orders that would finance the fixed
replenishment cost. We show that a Bayesian Nash equilibrium exists and characterize the equilibrium
in this game. We also show that the contributions are monotone increasing in each firm’s type. We finally
conduct a numerical study to compare the equilibrium to solutions obtained under independent and
cooperative ordering, and under full information. The results show that while information asymmetry
eliminates free-riding in the contributions game, the resulting aggregate contributions are not as high
as under full information, leading to higher aggregate costs.
2013 Elsevier B.V. All rights reserved
- …