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41.
42.
In this work we extend previous results on moment-based characterization and minimal representation of stationary Markovian arrival processes (MAPs) and rational arrival processes (RAPs) to transient Markovian arrival processes (TMAPs) and Markovian binary trees (MBTs). 相似文献
43.
Sophie Gordon 《History of Photography》2013,37(3)
Abstract Since the discovery of photography, the camera has been a silent witness at countless theatres of war, presenting a story that is ofteh as objective as any written account. The conflicts in the Crimea and in India in the 1850s were the first to allow the photographer an opportunity to report publicly on the progress of a war. Given the developments in photographic techniques, however, the camera still lagged some distance behind the main action and was usually relegated to documneting the carnage left in the wake of a victorious force. Omar Khan's book tells many stories, but perhaps the most presistent and enthralling is the journey of the photographer from the back of the army, straught into the frontline in Afghanistan. The story is surprisingly emotional, as a thrilling narrative of tribal war and the history of the British Raj are interwoven into the lives of two relatively forgotten men who devoted theri lives to photography. 相似文献
44.
N. Chasserio S. Guillemet-Fritsch T. Lebey S. Dagdag 《Journal of Electronic Materials》2009,38(1):164-174
One of the most attractive ways to increase power handling capacity in power modules is to increase the operating temperature
using wide-band-gap semiconductors. Ceramics are ideal candidates for use as substrates in high-power high-temperature electronic
devices. The present article aims to determine the most suitable ceramic material for this application. 相似文献
45.
Sophie Watson 《Urban Policy and Research》2013,31(2):159-170
Abstract This paper has two objectives. One is to explore the new terrain of homelessness from a gendered perspective in order to suggest ways in which the material experience of homelessness may have changed over the last fifteen years. The second objective is to look at the question through a different critical lens and explore what new theoretical paradigms have to offer to understanding homelessness, particularly the homelessness of women. 相似文献
46.
Wenceslao T. Medina Sophie Laurent Enrique Brandan José M. Aguilera 《Journal of food science》2010,75(3):E194-E200
ABSTRACT: Surface liquid adhesion (SLA) and liquid absorption (LA) of tritiated liquids, including water and skim, low-fat, whole, and fat-enriched milks, by cornflakes (CF) and frosted flakes (FF) were determined by scintillation counting using water-[3H] at 0.5 μCi/mL. SLA or the liquid adhering to individual flakes after a short immersion period was the same for CF and FF in the case of water (approximately 0.011 μL mm−2 of flake) but were always higher for CF than for FF and increased as the fat content in milks augmented. LA of individual flakes, followed for 300 s of soaking, increased with time and was always higher for CF than for FF (for the same liquid), however, data did not follow a regular pattern. Flakes showed quite compact outer surfaces and an internal porous matrix composed of air cells of various sizes separated by dense walls of different thicknesses. This heterogeneous microstructure of individual flakes may be the cause of the lack of a simple kinetics during the soaking process. Previous results obtained by soaking a mass of flakes overestimated the uptake of fluid by individual because they included the liquid occluded between the flakes. 相似文献
47.
Franois Charollais Sophie Fonquernie Christophe Perrais Marc Perez Olivier Dugne Franois Cellier Grard Harbonnier Marie-Pierre Vitali 《Nuclear Engineering and Design》2006,236(5-6):534-2004
In the framework of the French V/HTR fuel development and qualification program, the Commissariat à l’Energie Atomique (CEA) and AREVA are conducting R&D projects covering the mastering of UO2 coated particle and fuel compact fabrication technology. To fulfill this task, a review of past knowledge, of existing technologies and a preliminary laboratory-scale work program have been conducted with the aim of retrieving the know-how on HTR coated particle and compact manufacture:
- • The different stages of UO2 kernel fabrication GSP process have been reviewed, reproduced and improved.
- • The experimental conditions for the chemical vapor deposition of coatings have been defined on dummy kernels and development of innovative characterization methods has been carried out.
- • Former CERCA compacting process has been reviewed and updated.
- • to recover and validate past knowledge,
- • to produce representative HTR TRISO fuel meeting industrial standards,
- • to permit the optimization of reference fabrication processes for kernels and coatings defined previously at a laboratory-scale and the investigation of alternative and innovative fuel design (UCO kernel, ZrC coating),
- • to test alternative compact process options and
- • to fabricate and characterize fuel required for irradiation and qualification purpose.
49.
Francis Gohin Sophie Loyer Michel Lunven Claire Labry Jean-Marie Froidefond Daniel Delmas Martin Huret Alain Herbland 《Remote sensing of environment》2005,95(1):29-46
In biological modelling of the coastal phytoplankton dynamics, the light attenuation coefficient is often expressed as a function of the concentrations of chlorophyll and mineral suspended particulate matter (SPM). In order to estimate the relationship between these parameters over the continental shelf of the northern Bay of Biscay, a set of in situ data has been gathered for the period 1998-2003 when SeaWiFS imagery is available. These data comprise surface measurements of the concentrations of total SPM, chlorophyll, and irradiance profiles from which is derived the attenuation coefficient of the photosynthetically available radiation, KPAR. The performance of the IFREMER look-up table used to retrieve the chlorophyll concentration from the SeaWiFS radiance is evaluated on this new set of data. The quality of the estimated chlorophyll concentration is assessed from a comparison of the variograms of the in situ and satellite-derived chlorophyll concentrations. Once the chlorophyll concentration is determined, the non living SPM, which is defined as the SPM not related to the dead or alive endogenous phytoplankton, is estimated from the radiance at 555 nm by inverting a semi-analytic model. This method provides realistic estimations of concentrations of chlorophyll and SPM over the continental shelf all over the year. Finally, a relationship, based on non living SPM and chlorophyll, is proposed to estimate KPAR on the continental shelf of the Bay of Biscay. The same formula is applied to non living SPM and chlorophyll concentrations, observed in situ or derived from SeaWiFS radiance. 相似文献
50.
Constraint Programming (CP) offers a rich modeling language of constraints embedding efficient algorithms to handle complex and heterogeneous combinatorial problems. To solve hard combinatorial optimization problems using CP alone or hybrid CP-ILP decomposition methods, costs also have to be taken into account within the propagation process. Optimization constraints, with their cost-based filtering algorithms, aim to apply inference based on optimality rather than feasibility. This paper introduces a new optimization constraint, cost-regular. Its filtering algorithm is based on the computation of shortest and longest paths in a layered directed graph. The support information is also used to guide the search for solutions. We believe this constraint to be particularly useful in modeling and solving Column Generation subproblems and evaluate its behaviour on complex Employee Timetabling Problems through a flexible CP-based column generation approach. Computational results on generated benchmark sets and on a complex real-world instance are given.A preliminary version of this paper appeared as [7]. This research was supported by the Mathematics of Information Technology and Complex Systems (MITACS) Internship program in association with Omega Optimisation Inc. (CA). 相似文献