5,578 research outputs found
Age UK Rotherham Hospital Aftercare Service: Evaluation of the pilot extension into UECC and AMU at TRFT
When Network Coding and Dirty Paper Coding meet in a Cooperative Ad Hoc Network
We develop and analyze new cooperative strategies for ad hoc networks that
are more spectrally efficient than classical DF cooperative protocols. Using
analog network coding, our strategies preserve the practical half-duplex
assumption but relax the orthogonality constraint. The introduction of
interference due to non-orthogonality is mitigated thanks to precoding, in
particular Dirty Paper coding. Combined with smart power allocation, our
cooperation strategies allow to save time and lead to more efficient use of
bandwidth and to improved network throughput with respect to classical RDF/PDF.Comment: 7 pages, 7 figure
Asymptotic Capacity and Optimal Precoding Strategy of Multi-Level Precode & Forward in Correlated Channels
We analyze a multi-level MIMO relaying system where a multiple-antenna
transmitter sends data to a multipleantenna receiver through several relay
levels, also equipped with multiple antennas. Assuming correlated fading in
each hop, each relay receives a faded version of the signal transmitted by the
previous level, performs precoding on the received signal and retransmits it to
the next level. Using free probability theory and assuming that the noise power
at the relay levels - but not at the receiver - is negligible, a closed-form
expression of the end-to-end asymptotic instantaneous mutual information is
derived as the number of antennas in all levels grow large with the same rate.
This asymptotic expression is shown to be independent from the channel
realizations, to only depend on the channel statistics and to also serve as the
asymptotic value of the end-to-end average mutual information. We also provide
the optimal singular vectors of the precoding matrices that maximize the
asymptotic mutual information : the optimal transmit directions represented by
the singular vectors of the precoding matrices are aligned on the eigenvectors
of the channel correlation matrices, therefore they can be determined only
using the known statistics of the channel matrices and do not depend on a
particular channel realization.Comment: 5 pages, 3 figures, to be published in proceedings of IEEE
Information Theory Workshop 200
Once despised now desired: innovative land use and management of multilayered Pumice Soils in the Taupo and Galatea areas, central North Island, New Zealand
The tour brings together innovative land use change and management associated with dairy farming, and land-based effluent disposal, on weakly weathered and multi-layered, glass-rich, Pumice Soils (Vitrands) in the Taupo and Galatea areas. These changes and their effects, together with environmental and sustainability issues, form a central theme of the trip. Four main stops are planned, two before lunch and two after: (1) plantation pine-to-dairy farm conversion and impacts, the Taupo eruption deposits (AD 232 ± 10) and the Taupo soil, at Tahorakuri; (2) overview of the application of secondary-treated wastewater and nitrogen leaching and uptake, Rotokawa; (3) a sequence of five Holocene tephras and buried soils, including Kaharoa eruption deposits (AD 1314 ± 12) and the Galatea soil, Smeith Farm, Murupara; and (4) enhancing pasture production on ânewâ soils formed by excavating and mixing (âflippingâ) buried soil horizons (paleosols) on Smeithâs farm. During the trip â which helps mark Waikato Universityâs 50th anniversary â we will see a spectacular range of volcanic and fluvial landscapes and deposits, together with impacts of tectonism, as we traverse the famous Taupo Volcanic Zone ((TVZ) in the central volcanic region. Landforms and soils dominated by tephras (volcanic ash) become generally younger towards the loci of volcanic activity. Extensive areas of soils have been formed repeatedly from the fragmental eruptive products of the two most frequently active and productive rhyolite (silica-rich) volcanic centres known, namely Taupo and Okataina. Thus soil stratigraphy and upbuilding pedogenesis form a second theme on the trip. The first part of the guidebook thus contains sections including (i) volcanism and its products, (ii) Quaternary volcanism in TVZ including deposits erupted recently from Taupo and Tarawera volcanoes from which Pumice Soils have been formed, (iii) tephra-derived soils including Pumice Soils, their classification, special problems, and (low) fertility, (iv) allophane and its formation, and (v) the interplay between geological and pedological processes relating to tephras (upbuilding pedogenesis). The second part then comprises notes and illustrations pertaining to each stop (note that figure and table numbers are self-contained at each stop, or not used). Broad overviews of the regionâs geology are covered by Leonard et al. (2010), and the soils are outlined by Rijkse and Guinto (2010) and S-map. Further compilations of data are available in tour guides by Lowe (2008) and Lowe et al. (2010)
Coupling quasi-phase matching: entanglement buildup in nonlinear waveguide arrays
Wavevector quasi-phase matching was devised in the 1960s as a way to boost
nonlinear interactions with efficient quantum noise squeezing as one
outstanding outcome. In the era of quantum technologies, we propose a new
coupling quasi-phase matching for efficient generation of multimode
downconverted quantum light in nonlinear waveguide arrays. We highlight this
technique achieving multimode quantum entanglement and Einstein-Podolsky-Rosen
steering buildup. We discuss the feasibility of this method with current
technology and demonstrate its competitiveness as a resource for continuous
variables quantum information.Comment: 9 pages, 5 figures, v2 closer to published versio
Zero supermode-based multipartite entanglement in nonlinear waveguides arrays
We show that arrays of nonlinear waveguides in the second
harmonic generation regime are a promising source of continuous-variable
entanglement. We indeed demonstrate analytically that optical arrays with odd
number of waveguides injected with the zero-eigenvalue fundamental supermode
entangle this fundamental supermode with a collective harmonic field. Moreover
the fundamental individual modes are multipartite entangled and their
entanglement grows with propagation length. The device is scalable, robust to
losses, does not rely on specific values of nonlinearity and coupling and is
easily realized with current technology. It thus stands as an unprecedented
candidate for generation of multipartite continuous-variable entanglement for
optical quantum information processing.Comment: Main text: 7 pages, 6 figures. Supplemental material: 5 pages, 2
figure. v2 closer to published versio
THE TRUE AND FAIR VIEW CONCEPT IN ROMANIA: A CASE STUDY OF CONCEPT TRANSFERABILITY
There is an enormous literature relating to the true and fair view (hereafter TFV). We are concerned with how the concept is actually perceived by various actors in an emerging economy which has only recently joined the European Union, i.e. Romania. Romania has a code law system with an obvious preference for the legal form. Two main steps have been taken for the purpose of our study. First, textual analysis of all accounting regulations has been performed with respect to the provisions regarding the TFV concept. Second, nine in-depth semi-structured interviews have been conducted with top representatives of the Romanian regulator, preparers, auditors and professional bodies. The perception on TFV depends firstly on the category: for auditors, this is a guide or a vital concept, closely related to substance over form, relevance and usefulness for users, while for regulators and preparers, TFV is primarily compliance with the rules.true and fair view ; true and fair view override ; Romania
Families and work: revisiting barriers to employment
"In recent years, considerable effort has been put into supporting parents to make the transition
into work. This study was commissioned by the Department for Work and Pensions (DWP) to explore whether these incentives were helping parents to overcome the barriers known to impede their engagement in the formal labour market.
The report is based on fieldwork conducted in 2009. However, the concluding chapter considers the significance of the findings in light of proposals for the introduction of the Universal Credit and other reforms of the tax and benefit systems proposed by the Coalition Government." - Page 1
Recent Progress in Plasmonic Colour Filters for Image Sensor and Multispectral Applications
Using nanostructured thin metal films as colour filters offers several important advantages, in particular high tunability across the entire visible spectrum and some of the infrared region, and also compatibility with conventional CMOS processes. Since 2003, the field of plasmonic colour filters has evolved rapidly and several different designs and materials, or combination of materials, have been proposed and studied. In this paper we present a simulation study for a single- step lithographically patterned multilayer structure able to provide competitive transmission efficiencies above 40% and contemporary FWHM of the order of 30 nm across the visible spectrum. The total thickness of the proposed filters is less than 200 nm and is constant for every wavelength, unlike e.g. resonant cavity-based filters such as Fabry-Perot that require a variable stack of several layers according to the working frequency, and their passband characteristics are entirely controlled by changing the lithographic pattern. It will also be shown that a key to obtaining narrow-band optical response lies in the dielectric environment of a nanostructure and that it is not necessary to have a symmetric structure to ensure good coupling between the SPPs at the top and bottom interfaces. Moreover, an analytical method to evaluate the periodicity, given a specific structure and a desirable working wavelength, will be proposed and its accuracy demonstrated. This method conveniently eliminate the need to optimize the design of a filter numerically, i.e. by running several time-consuming simulations with different periodicities. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
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