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991.
Vedad Hulusic Carlo Harvey Kurt Debattista Nicolas Tsingos Steve Walker David Howard Alan Chalmers 《Computer Graphics Forum》2012,31(1):102-131
In recent years research in the three‐dimensional sound generation field has been primarily focussed upon new applications of spatialized sound. In the computer graphics community the use of such techniques is most commonly found being applied to virtual, immersive environments. However, the field is more varied and diverse than this and other research tackles the problem in a more complete, and computationally expensive manner. Furthermore, the simulation of light and sound wave propagation is still unachievable at a physically accurate spatio‐temporal quality in real time. Although the Human Visual System (HVS) and the Human Auditory System (HAS) are exceptionally sophisticated, they also contain certain perceptional and attentional limitations. Researchers, in fields such as psychology, have been investigating these limitations for several years and have come up with findings which may be exploited in other fields. This paper provides a comprehensive overview of the major techniques for generating spatialized sound and, in addition, discusses perceptual and cross‐modal influences to consider. We also describe current limitations and provide an in‐depth look at the emerging topics in the field. 相似文献
992.
993.
Experimental and numerical study of interactions between sprinklers and natural smoke vents
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Nicolas Trévisan Pascal Boulet Zoubir Acem Alexandre Jenft Grégoire Pianet Arnaud Breton Armelle Muller 《火与材料》2018,42(3):247-254
Real scale experimentations have been conducted in order to investigate interactions that may occur in a compartment where sprinklers and Smoke and Heat Exhaust Vent Systems coexist. Fuel oil spray was used as fire source with steady heat release rate of 400 and 800 kW. Both sprinkler system and natural Smoke and Heat Exhaust Vent Systems were designed according to the French standards. Effect of vent on sprinkler activation time was studied. An analysis of the temperature field inside the compartment was conducted while vent was opened prior or after sprinkler activation. Simulations of the experiments were also carried out with Fire Dynamics Simulator v.6 for validation purpose and also to provide supplementary data regarding soot flow rate and energy extracted at the vent. 相似文献
994.
Numerous sets of single‐particle breakage experiments are required in order to provide a sufficient database for improving the modeling of fluid particle breakage mechanisms. This work focuses on the interpretation of the physical breakage events captured on video. In order to extract the necessary information required for modeling the mechanisms of the fluid particle breakage events in turbulent flows, a well‐defined image analysis procedure is necessary. Two breakage event definitions are considered, namely, initial breakup and cascade breakup. The reported breakage time, the number of daughter particles created, and the daughter size distribution are significantly affected by the definition used. For each breakage event definition, an image analysis procedure is presented. 相似文献
995.
Nicolas Gauger Andrea Walther Emre ?zkaya Carsten Moldenhauer 《Optimization and Engineering》2012,13(4):563-578
In this paper, we consider an optimization problem for the complete design chain of an airfoil. Starting with a parameter vector, one has to perform a three step procedure to evaluate the desired objective: Generate a grid around the airfoil, compute the flow around the airfoil, and compute the objective. Applying a gradient-based optimization method, one has to provide derivatives for this complex process. In the present paper, we propose the advanced use of automatic differentiation to compute the required gradient information. We report numerical results together with a mesh independency study and an analysis of the optimization process for an inviscid RAE2822 airfoil under transonic flight conditions. 相似文献
996.
997.
Kornél Nagy Karine Redeuil Sabine Lahrichi Marine Nicolas 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(5):712-721
This paper reports the first results on depleting certain organochlorines from vegetable oils without the use of any solvent in order to mitigate monochloropropanediol diesters (MCDPE). The concept is based on separating the organochlorines from the bulk oil by using trapping agents (e.g. monoacylglycerols) that can be easily separated from the oil. The process starts by mixing and homogenizing crude vegetable oils with the trapping agent and subsequently separating the trapping agent from the oil bulk via crystallization. The proof-of-concept of the approach is demonstrated on a spiked sunflower model system, solvent extracted crude sunflower oil, industrially produced crude soybean and corn oils. The depletion of organochlorines in the crude oils and its beneficial effect on the MCPDE content in the heat treated samples is measured by LC-MS. The depletion efficacy of the monitored organochlorines was estimated to be in the 60–95 % range. Both the melting point and polarity of the trapping agents affected the depletion efficacy of the organochlorines. Trapping agents with higher melting point and polarity, such as monostearin were more effective in comparison to high melting point but less polar agents such as palm stearin or agents rich in polar but low melting point monolinolein/monoolein. The effect of organochlorine depletion on the subsequent MPCDE levels in heat treated oil was in the range of 60–90 % reduction depending on the type of the studied oil. 相似文献
998.
999.
Nicolas Perciani de Moraes Leticia Araujo Bacetto Gabriela Spirandelli dos Santos Maria Lucia Caetano Pinto da Silva João Paulo Barros Machado Tiago Moreira Bastos Campos Gilmar Patrocínio Thim Liana Alvares Rodrigues 《Ceramics International》2019,45(3):3657-3667
This paper reports the development of new ZnO/carbon xerogel composites (XZn w) for photocatalytic applications. The use of black wattle tannin as a precursor to the carbon xerogel aimed at reducing costs and environmental impacts. The composites were characterized by diffuse reflectance spectroscopy (DRS), BET surface area, scanning electron microscopy (FEG-SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), infrared spectroscopy (IR), and X-ray diffraction (XRD). The photocatalytic performance of the materials was evaluated in the decomposition process of methylene blue, a known toxic pollutant. The impacts of the catalyst dosage and calcination temperature on the photocatalytic process were also examined systematically. The X-ray profiles of the XZn w evidenced the existence of the hexagonal structure of the zinc oxide (wurtzite) in the composites. The XPS and XRD analyses confirmed the incorporation of carbon in the zinc oxide crystalline structure. The higher carbon content resulted in a larger surface area. All composites presented the ability to absorb radiation in less energetic wavelengths, contrary to pure zinc oxide that only absorbs radiation of wavelengths below 420?nm. The optimal dosage and calcination temperature were found to be 0.2?g?L?1 and 300?°C. All the developed composites displayed significant photocatalytic activities in the decomposition of methylene blue under both visible and solar light. The composites had superior photocatalytic efficiency under visible light when compared to pure zinc oxide. The XZn 0.5 presented the best degradation efficiency under visible radiation. All materials presented similar photocatalytic responses under solar light, evidencing the synergy between the carbon xerogel and the zinc oxide. The photocatalytic mechanism was evaluated by trapping experiments to be mainly controlled by the electron vacancies that are generated during the photoexcitation of the composites. 相似文献
1000.
Ashkhen YesayanFabien Prégaldiny Nicolas ChevillonChristophe Lallement Jean-Michel Sallese 《Solid-state electronics》2011,62(1):165-173
A physical and explicit compact model for lightly doped FinFETs is presented. This design-oriented model is valid for a large range of silicon Fin widths and lengths, using only a very few number of model parameters. The quantum mechanical effects (QMEs), which are very significant for thin Fins below 15 nm, are included in the model as a correction to the surface potential. A physics-based approach is also followed to model short-channel effects (roll-off), drain-induced barrier lowering (DIBL), subthreshold slope degradation, drain saturation voltage, velocity saturation, channel length modulation and carrier mobility degradation. The quasi-static model is then developed and accurately accounts for small-geometry effects as well. This compact model is accurate in all regions of operation, from weak to strong inversion and from linear to saturation regions. It has been implemented in the high-level language Verilog-A and exhibits an excellent numerical efficiency. Finally, comparisons of the model with 3D numerical simulations show a very good agreement making this model well-suited for advanced circuit simulations. 相似文献