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41.
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The smart grid is promoted as one of the key elements in a low-carbon transition in many countries. In Denmark, the dominant framing of the smart grid emphasises the challenge of integrating much more wind power into the electricity system and using electricity for heating (heat pumps) and transport (electric cars). In the process of radically transforming the electricity system, strategic system builders need to align many forces, including consumers, who play an important role in the functioning of such large networked systems. System builders need to explore, for instance, whether and how users can be motivated to be flexible in relation to moving electricity consumption over time. This paper reports on one of the first smart-grid-related projects in Denmark in which consumer aspects have been central and where potentials for flexible electricity consumption have been tested. The aim of the paper is to explore what can be learned from such experiments and which roles they play in the construction of the smart grid. In this context, the concept of the ‘aligned user’ is introduced. 相似文献
43.
Oula El Korhani Doumit Zaouk Sophie Cerneaux Randa Khoury Antonio Khoury David Cornu 《Nanoscale research letters》2013,8(1):121
Hydrothermal carbonization (HTC) process of beer wastes (Almaza Brewery) yields a biochar and homogeneous carbon-based nanoparticles (NPs). The NPs have been used to prepare carbon membrane on commercial alumina support. Water filtration experiments evidenced the quasi-dense behavior of the membrane with no measurable water flux below an applied nitrogen pressure of 6 bar. Gas permeation tests were conducted and gave remarkable results, namely (1) the existence of a limit temperature of utilization of the membrane, which was below 100°C in our experimental conditions, (2) an evolution of the microstructure of the carbon membrane with the operating temperature that yielded to improved performances in gas separation, (3) the temperature-dependent gas permeance should follow a Knudsen diffusion mechanism, and (4) He permeance was increasing with the applied pressure, whereas N2 and CO2 permeances remained stable in the same conditions. These results yielded an enhancement of both the He/N2 and He/CO2 permselectivities with the applied pressure. These promising results made biomass-sourced HTC-processed carbon membranes encouraging candidates as ultralow-cost and sustainable membranes for gas separation applications. 相似文献
44.
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
45.
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
46.
Slim Abdelkafi Benjamin Fouquet Nathalie Barouh Sophie Durner Michel Pina Frantz Scheirlinckx Pierre Villeneuve Frédéric Carrière 《Food chemistry》2009
High levels of lipase activity are known to occur in Carica papaya latex, and this activity is being used in some biotechnological applications. The lipolytic activity of C. papaya lipase (CPL) on dietary triacylglycerols (TAG) has not yet been studied. Hence, the aim of this study was to characterise the specific activity of CPL on dietary TAG present in a crude preparation. Also, we have determined its stability during the lipolysis of a test meal at various pH values mimicking those occurring in the gastro-intestinal tract, with or without bile, and have compared these properties with those of porcine pancreatic extract (PPE) and human pancreatic lipase (HPL). CPL showed maximum stability at pH 6.0, both with and without bile. Some residual activity was still observed at pH 2 (20%), whereas the pancreatic lipases tested were immediately completely inactivated at this pH. In the absence of bile, the highest specific activities were measured at pH 6 in the case of CPL, PPE and HPL. Adding bile slightly decreased the CPL activity in the 4–6 pH range, thus shifting the optimum CPL activity to pH 7, where the presence of bile had no effect. Lipolysis levels decreased with the pH, but CPL was still more active than PPE at pH 5 on a relative basis. These results suggest that CPL might be a promising candidate for use as a therapeutic tool on patients with pancreatic exocrine insufficiency. 相似文献
47.
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
48.
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
49.
Kaida Xiao Sophie Wuerger Chenyang Fu Dimosthenis Karatzas 《Color research and application》2011,36(5):316-323
Psychophysical experiments were conducted to assess unique hues on a CRT display for a large sample of colour‐normal observers (n = 185). These data were then used to evaluate the most commonly used colour appearance model, CIECAM02, by transforming the CIEXYZ tristimulus values of the unique hues to the CIECAM02 colour appearance attributes, lightness, chroma and hue angle. We report two findings: (1) the hue angles derived from our unique hue data are inconsistent with the commonly used Natural Color System hues that are incorporated in the CIECAM02 model. We argue that our predicted unique hue angles (derived from our large dataset) provide a more reliable standard for colour management applications when the precise specification of these salient colours is important. (2) We test hue uniformity for CIECAM02 in all four unique hues and show significant disagreements for all hues, except for unique red which seems to be invariant under lightness changes. Our dataset is useful to improve the CIECAM02 model as it provides reliable data for benchmarking. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011 相似文献
50.
Michael George A.; Garcia Sophie; Fernandez Damien; Sellal Fran?ois; Boucart Muriel 《Canadian Metallurgical Quarterly》2006,120(2):447
The authors tested a patient suffering from a circumscribed lesion of the right frontal operculum (FO) in 3 experiments of visual attention involving spatial orienting, maintenance of task-relevant priorities, and control of interference from new and old task-irrelevant items. The authors found that spatial orienting and active maintenance of priorities were intact, but there were difficulties in controlling interference from new and old irrelevant items. These results suggest that the FO is necessary for the direct control of interference, but its lesion alone is not enough to disturb spatial orienting processes or active maintenance of task priorities. The authors discuss the results in light of a hybrid cognitive model of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献