913,587 research outputs found
The 2D/3D dynamics of wall-bounded low-Rm magnetohydrodynamic (MHD) turbulence
With this experimental study, we give evidence that the dynamics of low-Rm MHD turbulence depends on the diffusion length l_z, which corresponds to the distance over which the Lorentz force is able to diffuse momentum before it is balanced by inertia
Low-energy scales and temperature-dependent photoemission of heavy fermions
We solve the S = 1/2 Kondo lattice model within the dynamical mean field theory. Detailed predictions are made for the dependence of the lattice Kondo resonance and the conduction electron spectral density on temperature and band filling, n(c). Two low-energy scales are identified in the spectra: a renormalized hybridization pseudogap scale T*, which correlates with the single-ion Kondo scale, and a lattice Kondo scale T-0 much less than T*, which acts as the Fermi-liquid coherence scale. The lattice Kondo resonance is split into a main branch, which is pinned at the Fermi level, and whose width is set by T-0, and an upper branch at omega approximate to T*. The weight of the upper branch decreases rapidly away from n(c) = 1 and vanishes for n(c) less than or similar to 0.7 (however, the pseudogap in the conduction electron spectral density persists for all n(c)). On increasing temperature, we find that the lattice Kondo resonance vanishes on a temperature scale of order 10T(0), the same scale over which the single-ion Kondo resonance vanishes in impurity model calculations. In contrast to impurity model calculations, however, we find that the position of the lattice Kondo resonance depends strongly on temperature. The results are used to make predictions on the temperature dependence of the low-energy photoemission spectrum of metallic heavy fermions and doped Kondo, insulators. We compare our results for the photoemission spectra with available high-resolution measurements on YbInCu4 and YbAgCu4. The loss in intensity with increasing temperature, and the asymmetric lineshape of the low-energy spectra are well accounted for by our simplified S = 1/2 Kondo lattice model
Rapid review of evidence about the optimal primary vaccination schedule for pertussis: Draft Report
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
We create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Power Minimisation Techniques for Testing Low Power VLSI Circuits (PhD Dissertation)
Testing low power very large scale integrated (VLSI) circuits has recently become an area of concern due to yield and reliability problems. This dissertation focuses on minimising power dissipation during test application at logic level and register-transfer level (RTL) of abstraction of the VLSI design flow. The first part of this dissertation addresses power minimisation techniques in scan sequential circuits at the logic level of abstraction. A new best primary input change (BPIC) technique based on a novel test application strategy has been proposed. The technique increases the correlation between successive states during shifting in test vectors and shifting out test responses by changing the primary inputs such that the smallest number of transitions is achieved. The new technique is test set dependent and it is applicable to small to medium sized full and partial scan sequential circuits. Since the proposed test application strategy depends only on controlling primary input change time, power is minimised with no penalty in test area, performance, test efficiency, test application time or volume of test data. Furthermore, it is shown that partial scan does not provide only the commonly known benefits such as less test area overhead and test application time, but also less power dissipation during test application when compared to full scan. To achieve power savings in large scan sequential circuits a new test set independent multiple scan chain-based technique which employs a new design for test (DFT) architecture and a novel test application strategy, is presented. The technique has been validated using benchmark examples, and it has been shown that power is minimised with low computational time, low overhead in test area and volume of test data, and with no penalty in test application time, test efficiency, or performance. The second part of this dissertation addresses power minimisation techniques for testing low power VLSI circuits using built-in self-test (BIST) at RTL. First, it is important to overcome the shortcomings associated with traditional BIST methodologies. It is shown how a new BIST methodology for RTL data paths using a novel concept called test compatibility classes (TCC) overcomes high test application time, BIST area overhead, performance degradation, volume of test data, fault-escape probability, and complexity of the testable design space exploration. Second, power minimisation in BIST RTL data paths is achieved by analysing the effect of test synthesis and test scheduling on power dissipation during test application and by employing new power conscious test synthesis and test scheduling algorithms. Third, the new BIST methodology has been validated using benchmark examples. Further, it is shown that when the proposed power conscious test synthesis and test scheduling is combined with novel test compatibility classes simultaneous reduction in test application time and power dissipation is achieved with low overhead in computational time
Wide-bandwidth low-loss 19-cell hollow core photonic band gap fiber and its potential for low latency data transmission
A record low loss (3.5dB/km) for a wide operating bandwidth HC-PBGF is reported. Detailed time-of-flight measurements are also presented, enabling first measurements of latency and differential group delay between mode groups in HC-PBGF
The vanishing author in computer-generated works: a critical analysis of recent Australian case law
Abstract
The use of software is ubiquitous in the creation of many copyright works, yet the requirement in copyright law that every work have a human author who engages in independent intellectual effort means that its use may prevent copyright subsistence. Several recent Australian cases have refocused attention on authorship as an essential criterion of copyright subsistence, and these cases suggest that much computer-produced output may be authorless and thus lack copyright protection. This article, the first in a two-part series, analyses how each case deals with the question of authorship of computer-produced works and why the use of software diminishes copyright protection for a significant number of computer-generated works. The article critiques the application of conventional notions of human authorship developed in the pre-computer age to modern productions and suggests alternative approaches to authorship that satisfy both the major objectives of copyright policy and the need to adapt to the computer age. The article argues that, without a broader judicial approach to authorship of computer-generated works, Parliament must remedy the lacuna in protection for these ‘authorless’ works. Possible solutions for reform are suggested. In a forthcoming article, the author comprehensively examines those reform proposals
Exact two-dimensionalization of low-magnetic-Reynolds-number flows subject to a strong magnetic field
We investigate the behavior of flows, including turbulent flows, driven by a horizontal body-force and subject to a vertical magnetic field, with the following question in mind: for very strong applied magnetic field, is the flow mostly two-dimensional, with remaining weak three-dimensional fluctuations, or does it become exactly 2D, with no dependence along the vertical? We restrict attention to low-magnetic-Reynolds number (Rm) flow. Because liquid metals have low magnetic Prandtl number, such low- flows can have a kinetic Reynolds number as large as one million and therefore be strongly turbulent. We first focus on the quasi-static approximation, i.e. the asymptotic limit of vanishing magnetic Reynolds number Rm << 1: we prove that the flow becomes exactly 2D asymptotically in time, regardless of the initial condition and provided the interaction parameter N is larger than a threshold value. We call this property absolute two-dimensionalization: the attractor of the system is necessarily a (possibly turbulent) 2D flow. We then consider the full-magnetohydrodynamic equations and we prove that, for low enough Rm and large enough N, the flow becomes exactly two-dimensional in the long-time limit provided the initial vertically-dependent perturbations are infinitesimal. We call this phenomenon linear two-dimensionalization: the (possibly turbulent) 2D flow is an attractor of the dynamics, but it is not necessarily the only attractor of the system. Some 3D attractors may also exist and be attained for strong enough initial 3D perturbations. These results shed some light on the existence of a dissipative anomaly for magnetohydrodynamic flows subject to a strong external magnetic field
Ratio of n-6/n-3 in the diets of beef cattle
Effects of feeding heat-treated canola (C), soybean (S) and flax (F) or mixtures on growth and slaughter characteristics, taste and fatty acid (FA) composition of beef tissue were investigated using 128 crossbred steers to determine the potential of improving the nutritional quality of beef for humans. For Trial 1 (48 steers), dietary treatments were: roasted C, extruded C, roasted S, extruded S, roasted F and extruded F. For Trial 2 (80 steers), the dietary treatments were: S:F (1:1), S:C (1:1), C:F (1:1) and S:F:C (1:1:1), and the oilseeds were processed either by roasting or extruding before mixing. Soybean meal and soybean oil were used to give equivalent lipid and protein contents to each experimental diet. The basal diet consisted of grass silage, barley grain, vitamins and minerals. Steers were fed for a minimum of 100d then slaughtered at a uniform degree of finish. Growth and slaughter characteristics of the steers were only slightly affected by dietary treatment in that the soybean-fed steers consumed more feed and had a higher average daily gain than the canola or flax-fed animals in Trial 1. There was no difference in taste panel parameters for any of the treatments. Inclusion of flax in the diet increased the total n-3 content of meat. Similar results were found for canola and C18:1n-9 although this was not the case for soybean and the n-6 FA. For the n-6 FA in the PL and neutral lipid fractions of the meat samples, levels were correlated with high dietary levels of n-6 or n-9 with low levels of n-3 while for the n-3 FA, levels were correlated with high dietary n-3 levels and low n-6 levels. Oilseed processing method did not have an effect on any fatty acid levels. It is possible to modify the FA composition of beef meat toward a healthier profile by including heat-treated oilseeds in the diet to influence the degree of lipid metabolism in the rumen.ID: S0377840111004007; M3: Article; Accession Number: S0377840111004007; Author: M.A. McNiven (a, ⁎); Author: J.L. Duynisveld (b); Author: T. Turner (a); Author: A.W. Mitchell (a); Affiliation: Department of Health Management, Atlantic Veterinary College, University of PEI, Charlottetown, PEI, Canada C1A 4P3; Affiliation: Agriculture and Agri-Food Canada, Nappan, NS, Canada B0L 1C0; Keyword: Oilseeds; Keyword: Roasted; Keyword: Extruded; Keyword: Fatty acids; Keyword: Healthy fat; Number of Pages: 11; Language: English
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