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41.
42.
Catherine Soladié Nicolas Stoiber Renaud Séguier 《Computer Vision and Image Understanding》2013,117(11):1598-1609
Facial expressions analysis plays an important part in emotion detection. However, having an automatic and non-intrusive system to detect blended facial expression is still a challenging problem, especially when the subject is unknown to the system. Here, we propose a method that adapts to the morphology of the subject and that is based on a new invariant representation of facial expressions. In our system, one expression is defined by its relative position to 8 other expressions. As the mode of representation is relative, we show that the resulting expression space is person-independent. The 8 expressions are synthesized for each unknown subject from plausible distortions. Recognition tasks are performed in this space with a basic algorithm. The experiments have been performed on 22 different blended expressions and on either known or unknown subjects. The recognition results on known subjects demonstrate that the representation is robust to the type of data (shape and/or texture information) and to the dimensionality of the expression space. The recognition results on 22 expressions of unknown subjects show that a dimensionality of the expression space of 4 is enough to outperform traditional methods based on active appearance models and accurately describe an expression. 相似文献
43.
Vincent Bizet Xavier Pannecoucke Jean‐Luc Renaud Dominique Cahard 《Advanced Synthesis \u0026amp; Catalysis》2013,355(7):1394-1402
The ruthenium–2‐propanol combination was found to transform γ‐trifluoromethylated allylic alcohols and β‐trifluoromethylated enones into the corresponding saturated alcohols in excellent yields via a one‐pot tandem process involving isomerization and transfer hydrogenation(s). High stereospecificity was demonstrated and evidence for two mechanistic pathways is provided. The method was applied to a rapid synthesis of trifluoromethylated citronellol. 相似文献
44.
Hajer Trabelsi Olfa Aicha CherifFaouzi Sakouhi Pierre VilleneuveJustin Renaud Nathalie BarouhSadok Boukhchina Paul Mayer 《Food chemistry》2012,131(2):434-440
This research has determined oil, fatty acid and sterol contents of the Tunisian Pistacialentiscus (Lentisc) fruits during maturation. Low oil accumulation was observed during the first 35 days after the fruiting (DAF) date (from 1.83% to 2.57%). After that, two phases were distinguished (35th until the 60th and 105th to the 145th DAF), where the rate of oil accumulation increased significantly. At the last stage of maturation, the lentisc fruits had the highest percentage of lipid content, 42.54%. The changing profile of fatty acids during maturation had been marked mainly by an increase in oleic acid content (from 19.49% to 50.72%) paralleling a decrease in linoleic acid content (from 42.5% to 21.75%). At the 15th DAF, the alpha-linolenic acid was found with a maximum of 13.81%. At full maturity, the main fatty acids were oleic acid, followed by palmitic and linoleic acid. Other fatty acids were present in trace proportions, such as palmitoleic, stearic, linolenic, gadoleic and arachidic acid. In all stages of ripening only four sterols were identified and quantified. β-Sitosterol was the major 4-desmethylsterol in samples tested, followed by campesterol. Cholesterol and stigmasterol were detected in trace amounts. During the first stage of ripening, the amount of total sterols was about 5.19/100 g of oil. It decreased to 0.43/100 g in the last stage. Sitosterol and campesterol showed nearly the same profile during the ripening of P. lentiscus fruit which could be linked to the relation between these compounds during their biosynthesis. 相似文献
45.
Inspired by the Multiplicative Exponential fragment of Linear Logic, we define a framework called the prismoid of resources where each vertex is a language which refines the λ-calculus by using a different choice to make explicit or implicit (meta-level) the definition of the contraction, weakening, and substitution operations. For all the calculi in the prismoid we show simulation of β-reduction, confluence, preservation of β-strong normalisation and strong normalisation for typed terms. Full composition also holds for all the calculi of the prismoid handling explicit substitutions. The whole development of the prismoid is done by making the set of resources a parameter of the formalism, so that all the properties for each vertex are obtained as a particular case of the general abstract proofs. 相似文献
46.
Ali Nour Bruno Massicotte Renaud De Montaignac Jean-Philippe Charron 《Cement and Concrete Research》2011,(9):964-974
This study is aimed at proposing a simple analytical model to investigate the post-cracking behaviour of FRC panels, using an arbitrary tension softening, stress crack opening diagram, as the input. A new relationship that links the crack opening to the panel deflection is proposed. Due to the stochastic nature of material properties, the random fibre distribution, and other uncertainties that are involved in concrete mix, this relationship is developed from the analysis of beams having the same thickness using the Monte Carlo simulation (MCS) technique. The softening diagrams obtained from direct tensile tests are used as the input for the calculation, in a deterministic way, of the mean load displacement response of round panels. A good agreement is found between the model predictions and the experimental results. 相似文献
47.
Difficulties in isolating and purifying antibiotic fatty acids from culture filtrates of Pseudozyma flocculosa, a biocontrol agent against powdery mildew, have been limiting factors in studying the properties and understanding the mode of action of the biocontrol agent. We report a new protocol for synthesizing (Z)-9-heptadecenoic and for the first time synthesis of (Z)-6-methyl-9-heptadecenoic acids, two antibiotic fatty acids produced by P. flocculosa. This allowed reproducible and quantifiable means of assaying biological activity of the molecules. In these bioassays, both molecules exhibited antifungal activity corresponding to their expected potency. These new developments should facilitate further studies aimed at deciphering the ecological properties of P. flocculosa. 相似文献
48.
Dipak Chandra Das Dipankar Sanyal Renaud Meignen 《Numerical Heat Transfer, Part A: Applications》2013,63(10):1112-1130
A numerical model is developed to study mixed convection film boiling over a vertical flat plate. The integral form of conservation equations for each phase along with the appropriate interface conditions due to phase change is transformed into ordinary differential equation (ODE)-form. The length scale used in the model is based on Rayleigh–Taylor instability wave at the liquid–vapor interface. The heat transfer associated in the process is assessed and results are validated successfully for different available experimental results for natural convection and mixed convection film boiling. The mixed convection film boiling is characterized in terms of relevant nondimensional parameters for each phase. 相似文献
49.
A large number of researchers have paid great attention to solar chimney (SC) power generating technology, but only a few have studied the chimney configuration. Taking a 10 MW SC system as an example, the physical and mathematical models illustrating the fluid flow, heat transfer and output power features of the system are established. Based on constraints such as equal chimney bottom section area or equal chimney surface area, the impact of several sizes of three different chimney configurations upon the chimney outlet air temperature and velocity, system output power and efficiency is analyzed and the influence of the height‐to‐diameter ratio (H/D) of the cylindrical chimney on system performance is studied as well. After a comprehensive analysis of system output power and efficiency, it is proved by the numerical simulation that the cylindrical chimney would be the best choice among the three basic configurations, whose optimum H/D value ranges from 6 to 8. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
50.
Selection of an adsorbent for lead removal from drinking water by a point-of-use treatment device 总被引:6,自引:0,他引:6
The removal of lead from drinking water was investigated to develop a point-of-use water filter that could meet the regulation imposed by the new European Directive 98-83 lowering lead concentration in drinking water below 10 μg L−1. The objective of this research was to assess the potential of different adsorbents (zeolites, resins, activated carbon, manganese oxides, cellulose powder) to remove lead from tap water with a very short contact time. To begin, the repartition of the lead species in a tap water and a mineral water was computed with the computer model CHESS. It showed that in bicarbonated waters lead is mainly under lead carbonate form, either in the aqueous or in the mineral phase. Batch experiments were then conducted to measure the equilibrium adsorption isotherms of the adsorbents. Then, for five of them, dynamic experiments in micro-columns were carried out to assess the outlet lead concentration level. Three adsorbents gave rise to a leakage concentration lower than 10 μg L−1 and were then selected for prototypes experiments: chabasite, an activated carbon coated with a synthetic zeolite and a natural manganese oxide. The proposed method clearly showed that the measurement of equilibrium isotherms is not sufficient to predict the effectiveness of an adsorbent, and must be coupled with dynamic experiments. 相似文献