VLBI observations of jupiter with the initial test station of LOFAR and the nancay decametric array

AIMS: To demonstrate and test the capability of the next generation of low-frequency radio telescopes to perform high resolution observations across intra-continental baselines. Jupiter's strong burst emission is used to perform broadband full signal cross-correlations on time intervals of up to hundreds of milliseconds. METHODS: Broadband VLBI observations at about 20 MHz on a baseline of ~50000 wavelengths were performed to achieve arcsecond angular resolution. LOFAR's Initial Test Station (LOFAR/ITS, The Netherlands) and the Nancay Decametric Array (NDA, France) digitize the measured electric field with 12 bit and 14 bit in a 40 MHz baseband. The fine structure in Jupiter's signal was used for data synchronization prior to correlation on the time-series data. RESULTS: Strong emission from Jupiter was detected during snapshots of a few seconds and detailed features down to microsecond time-scales were identified in dynamic spectra. Correlations of Jupiter's burst emission returned strong fringes on 1 ms time-scales over channels as narrow as a hundred kilohertz bandwidth. CONCLUSIONS: Long baseline interferometry is confirmed at low frequencies, in spite of phase shifts introduced by variations in ionospheric propagation characteristics. Phase coherence was preserved over tens to hundreds of milliseconds with a baseline of ~700 km. No significant variation with time was found in the correlations and an estimate for the fringe visibility of 1, suggested that the source was not resolved. The upper limit on the source region size of Jupiter Io-B S-bursts corresponds to an angular resolution of ~3 arcsec. Adding remote stations to the LOFAR network at baselines up to thousand kilometers will provide 10 times higher resolution down to an arcsecond.Comment: 6 pages, 4 figures. Nigl, A., Zarka, P., Kuijpers, J., Falcke, H., Baehren, L., VLBI observations of Jupiter with the Initial Test Station of LOFAR and the Nancay Decametric Array, A&A, 471, 1099-1104, accepted on 31/05/200

Determination of Traffic Parameters for the Prediction, Projection, and Computation of EWL’s

One of the first published methods for the structural design of highway pavements was called the Massachusetts Rule and was presented in the eighth annual report of the Massachusetts Highway Commission in 1901 (1). The essence of this procedure was a rather intuitive assumption concerning the distribution of vertical pressures beneath a loaded area. For design purposes, this required the selection of a design load which, since failure was assumed to be catastrophic and not cumulative, could be taken as the largest load that could reasonably be anticipated during the design life of the pavement. The prediction of such a design load was in itself a rather formidable task

An Improved Approximate Consensus Algorithm in the Presence of Mobile Faults

This paper explores the problem of reaching approximate consensus in synchronous point-to-point networks, where each pair of nodes is able to communicate with each other directly and reliably. We consider the mobile Byzantine fault model proposed by Garay '94 -- in the model, an omniscient adversary can corrupt up to $f$ nodes in each round, and at the beginning of each round, faults may "move" in the system (i.e., different sets of nodes may become faulty in different rounds). Recent work by Bonomi et al. '16 proposed a simple iterative approximate consensus algorithm which requires at least $4f+1$ nodes. This paper proposes a novel technique of using "confession" (a mechanism to allow others to ignore past behavior) and a variant of reliable broadcast to improve the fault-tolerance level. In particular, we present an approximate consensus algorithm that requires only $\lceil 7f/2\rceil + 1$ nodes, an $\lfloor f/2 \rfloor$ improvement over the state-of-the-art algorithms. Moreover, we also show that the proposed algorithm is optimal within a family of round-based algorithms

Optical properties and electronic structure of MgAuSn

The optical conductivity spectrum of single-crystal MgAuSn was measured by spectroscopic ellipsometry in the energy range 1.5–5.0 eV. The spectrum has a large peak at 2.9 eV and a small shoulder around 4.3 eV. The band structure, density of states, and interband contribution to the optical conductivity were calculated with the tight-binding linear muffin-tin orbital method in the atomic-sphere approximation. The intraband contribution to the optical conductivity was added using the Drude response fitted to the experimental data. The total theoretical spectrum, including the intraband contribution, agrees well with experimental data

Dynamical and spectral properties of complex networks

Dynamical properties of complex networks are related to the spectral properties of the Laplacian matrix that describes the pattern of connectivity of the network. In particular we compute the synchronization time for different types of networks and different dynamics. We show that the main dependence of the synchronization time is on the smallest nonzero eigenvalue of the Laplacian matrix, in contrast to other proposals in terms of the spectrum of the adjacency matrix. Then, this topological property becomes the most relevant for the dynamics.Comment: 14 pages, 5 figures, to be published in New Journal of Physic

Setting priorities to inform assessment of care homes’ readiness to participate in healthcare innovation: a systematic mapping review and consensus process

© 2020 The Author(s). This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedOrganisational context is known to impact on the successful implementation of healthcare initiatives in care homes. We undertook a systematic mapping review to examine whether researchers have considered organisational context when planning, conducting, and reporting the implementation of healthcare innovations in care homes. Review data were mapped against the Alberta Context Tool, which was designed to assess organizational context in care homes. The review included 56 papers. No studies involved a systematic assessment of organisational context prior to implementation, but many provided post hoc explanations of how organisational context affected the success or otherwise of the innovation. Factors identified to explain a lack of success included poor senior staff engagement, non-alignment with care home culture, limited staff capacity to engage, and low levels of participation from health professionals such as general practitioners (GPs). Thirty-five stakeholders participated in workshops to discuss findings and develop questions for assessing care home readiness to participate in innovations. Ten questions were developed to initiate conversations between innovators and care home staff to support research and implementation. This framework can help researchers initiate discussions about health-related innovation. This will begin to address the gap between implementation theory and practice.Peer reviewe

Differential Charge Sensing and Charge Delocalization in a Tunable Double Quantum Dot

We report measurements of a tunable double quantum dot, operating in the quantum regime, with integrated local charge sensors. The spatial resolution of the sensors is sufficient to allow the charge distribution within the double dot system to be resolved at fixed total charge. We use this readout scheme to investigate charge delocalization as a function of temperature and strength of tunnel coupling, showing that local charge sensing allows an accurate determination of interdot tunnel coupling in the absence of transport.Comment: related papers at http://marcuslab.harvard.ed