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61.
Clegg R.G. Withall M.S. Moore A.W. Phillips I.W. Parish D.J. Rio M. Landa R. Haddadi H. Kyriakopoulos K. Auge J. Clayton R. Salmon D. 《Communications, IET》2009,3(6):957-966
The production of a large-scale monitoring system for a high-speed network leads to a number of challenges. These challenges are not purely technical but also socio-political and legal. The number of stakeholders in such monitoring activity is large including the network operators, the users, the equipment manufacturers and, of course, the monitoring researchers. The MASTS project (measurement at all scales in time and space) was created to instrument the high-speed JANET lightpath network and has been extended to incorporate other paths supported by JANET(UK). Challenges the project has faced included: simple access to the network; legal issues involved in the storage and dissemination of the captured information, which may be personal; the volume of data captured and the rate at which these data appear at store. To this end, the MASTS system will have established four monitoring points each capturing packets on a high-speed link. Traffic header data will be continuously collected, anonymised, indexed, stored and made available to the research community. A legal framework for the capture and storage of network measurement data has been developed which allows the anonymised IP traces to be used for research purposes. 相似文献
62.
Stout Julie C.; Bondi Mark W.; Jernigan Terry L.; Archibald Sarah L.; Delis Dean C.; Salmon David P. 《Canadian Metallurgical Quarterly》1999,13(2):188
Twenty-seven research participants with dementia of the Alzheimer type were studied with the California Verbal Learning Test (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1987) and standardized volume measures of the mesial temporal cortical gray matter, neocortical gray matter, thalamus, and caudate nuclei, from magnetic resonance imaging. A pattern of atrophic brain changes in the mesial temporal lobes (MTL) and the thalamus, with relatively less severe atrophy in the neocortical gray matter, was associated with poorer learning of the word list. Similar patterns of brain atrophy were observed for measures of delayed recall and recognition hits. However, for delayed recall, neither contribution was statistically significant, and for recognition hits, MTL was only at the trend level for significance. These results provide evidence that the verbal memory deficit of Alzheimer's disease (AD) is associated not only with the mesial temporal limbic cortex, thought to be the site of earliest and most severe pathology in AD, but also with damage in the thalamus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
64.
The crystalline phases prepared by calcination at 350°C of amorphous iron molybdate precipitates with different chemical composition have been studied by magnetic susceptibility and EPR measurements. The magnetic susceptibility parameters and peak-to-peak resonance linewidth are defined for the stoichiometric Fe2(MoO4)3.At MotoFe ratios in the precursors higher than 1.5 the crystal products contain lattice defects changing the values of the intensive magnetic parameters. 相似文献
65.
Caroline Privault Jacki O’Neill Victor Ciriza Jean-Michel Renders 《Artificial Intelligence and Law》2010,18(4):459-479
This paper describes a tool for assisting lawyers and paralegal teams during document review in eDiscovery. The tool combines
a machine learning technology (CategoriX) and advanced multi-touch interface capable of not only addressing the usual cost,
time and accuracy issues in document review, but also of facilitating the work of the review teams by capitalizing on the
intelligence of the reviewers and enabling collaborative work. 相似文献
66.
Morphology development during the synthesis at room temperature of an interpenetrating polyurethane/poly(methyl methacrylate) network was investigated by small-angle X-ray scattering in relation with their relative kinetics of formation, determined by Fourier transform infra red spectroscopy. When the time lag between the onset of the two reactions is short, macroscopic phase separation occurs as the polyurethane network is incompletely formed. However, when the time lag increases, the poly(methyl methacrylate) forms into a more continuous network which limits the growth of phase separation to a close environment. 相似文献
67.
Automatic Creation of Object Hierarchies for Ray Tracing 总被引:7,自引:0,他引:7
Intersection calculations dominate the run time of canonical ray tracers. A common algorithm to reduce the number of intersection tests required is the intersection of rays with a tree of extents, rather than the whole database of objects. A shortcoming of this method is that these trees are difficult to generate. Additionally, manually generated trees can be poor, greatly reducing the run-time improvement available. We present methods for evaluation of these trees in approximate number of intersection calculations required and for automatic generation of good trees. These methods run in O(nlogn) expected time where n is the number of objects in the scene. We report some examples of speedups. 相似文献
68.
69.
Marcin Idczak Dominique Groleau Patrice Mestayer Jean-Michel Rosant Jean-François Sini 《Building and Environment》2010
This paper presents a validation of the thermo-radiative model SOLENE and its application for analysing the street canyon energy balance. The validation data were selected from the temperature and radiation measurements obtained during the JAPEX campaign, previously described by Idczak et al. [16]: a set of four lines of steel containers buildings composing three parallel street canyons at an approximate 1:5 scale. Reference weather data and micrometeorological conditions within the canyon were measured. Numerical simulations were carried out using the meteorological measurements as model inputs. The simulated surface temperatures and radiation fluxes are compared with the measurements for a full week period, with a focus on a day with clear sky conditions. The street canyon energy balance analysis demonstrates that the most energetic surface was the street ground due to its thick surface layer of tar-coated gravels while the walls had a low heat capacity. The thermal radiation balance was negative for all canyon surfaces. The sensible heat was transferred mainly from the canyon surfaces to the ambient air, but also from the air to the ground in the morning. The effective albedo of the canyon had a diurnal value of 0.20–0.25, but dropped to 0.10 in the afternoon when the ground strongly transformed the direct and reflected solar radiation into sensible heat. This narrow street configuration enhanced solar radiation absorption and longwave radiation trapping. 相似文献
70.