High level visual scene classification using background knowledge of objects

Multimedia Tools and Applications - This paper introduces a novel and simple approach of high-level scene classification. Knowing that objects are the essence of any given scene, the proposed...     

Modeling and interpretations by the statistical physics formalism of hydrogen adsorption isotherm on LaNi4.75Fe0.25

Three theoretical expressions for the adsorption isotherms of hydrogen on LaNi_4.75Fe_0.25 alloy at 303 K and 313 K have been established. Our objective in this modeling is to select the adequate model that presents a high correlation with the experimental curves. The establishment of these new expressions is based on statistical physics formalism. This method has allowed the estimation of physicochemical parameters in the theoretical model. The parameters intervening in the adsorption process have been deduced directly from experimental adsorption isotherms by numerical simulation. We will mainly introduce four parameters affecting the adsorption process, namely; the density of hydrogen receptor sites N_M, the number of molecules per site and the hydrogen adsorption energy. Then we apply the model to calculate thermodynamics functions which govern the adsorption mechanism such as entropy, free enthalpy and internal energy.     

使用序批式反应器对灰水进行生物处理

本研究的目的是探讨序批式反应器技术在处理从学生宿舍淋浴器出口处收集的灰水中的应用。当排出水的COD和BOD分别为20mg／L和5mg／L时,SBR的性能是令人满意的。     

Combined Convective and Microwave Drying of Agglomerated Sand: Internal Transfer Modeling with the Gas Pressure Effect

In order to improve the industrial drying (hot air and microwave) of inserts made of agglomerated sand, a comprehensive internal heat and water transfer model has been proposed. In this model, the internal gas phase pressure effect was made perfectly explicit, especially the phenomena of liquid and vapour transfer by filtration and of liquid expulsion at the surface. This model was validated on the basis of the experimental mean water content and core temperature curves for drying trials at different microwave powers. Then, it was used for comparing the drying time and the internal pressure level calculated for four particular processes: a standard process with high temperature air applied all over the time, a strong process with high power microwaves applied all over, and two processes which alternate the two heating modes. It was demonstrated that the combined and alternative processes provide a real possibility for faster drying with less internal pressure and thus with less cracking risk. The microwaves should be applied only in the first hour of the process and with decreasing power. The decrease of the drying time was around 30% with regard to the hot air standard process.     

Spontaneous Outcropping of Self‐Assembled Insulating Nanodots in Solution‐Derived Metallic Ferromagnetic La0.7Sr0.3MnO3 Films

A new mechanism is proposed for the generation of self‐assembled nanodots at the surface of a film based on spontaneous outcropping of the secondary phase of a nanocomposite epitaxial film. Epitaxial self‐assembled Sr–La oxide insulating nanodots are formed through this mechanism at the surface of an epitaxial metallic ferromagnetic La_0.7Sr_0.3MnO₃ (LSMO) film grown on SrTiO₃ from chemical solutions. TEM analysis reveals that, underneath the La–Sr oxide (LSO) nanodots, the film switches from the compressive out‐of‐plane stress component to a tensile one. It is shown that the size and concentration of the nanodots can be tuned by means of growth kinetics and through modification of the La excess in the precursor chemical solution. The driving force for the nanodot formation can be attributed to a cooperative effect involving the minimization of the elastic strain energy and a thermodynamic instability of the LSMO phase against the formation of a Ruddelsden–Popper phase Sr₃Mn₄O₇ embedded in the film, and LSO surface nanodots. The mechanism can be described as a generalization of the classical Stranski–Krastanov growth mode involving phase separation. LSO islands induce an isotropic strain to the LSMO film underneath the island which decreases the magnetoelastic contribution to the magnetic anisotropy.     

Electrical and compositional properties of TaSi2 films

Tantalum silicide (TaSi₂) thin films were sputter deposited on p- and n-type silicon substrates using ultrapure TaSi₂ targets. The TaSi₂/Si samples were annealed in nitrogen or forming gas or oxygen containing steam at temperatures in the range of 400–900°C. The sheet resistances of TaSi₂/Si were measured by four-point probe before and after anneal. The structure of these films was investigated using x-ray diffraction (XRD) methods. It has been found that the sheet resistance decreases with the increase in annealing temperature and also with the increase in film thickness. X-ray diffraction patterns show changes in the morphological structure of the films. Oxidation characteristics of the film have been investigated in the temperature range of 400–900°C in oxygen containing steam ambient. The oxidation time ranged from 0.5 to 1.5 h. No oxide formation of the tantalum silicide films was observed in this investigation. This has been attributed to the high purity of TaSi₂ sputter targets used in the preparation of the films.     

Occurrence of multidrug resistance in Campylobacter from Ivorian poultry and analysis of bacterial response to acid shock

The level of antibiotic multiresistance of Campylobacter strains from chicken was evaluated and responses to the bactericidal effects of organic acids were analyzed. Strains (76) isolated from chicken were analyzed for resistance to antibiotics and acid shock. A high strain resistance to fluoroquinolones (ciprofloxacin and nalidixic acid) was observed, with cross resistance to both drugs in 41% of strains. A low resistance was observed for amoxicillin, erythromycin, and gentamicin. Campylobacter jejuni was the most resistant species. Antibacterial activities against multiresistant Campylobacter strains were observed using acetic, citric, and ascorbic acids at minimum bactericidal concentrations (MBC) ranging from 0.3 to 3 mg/mL. Acetic acid was the most efficient acid with the lowest MBC value. However, a contact time of 4 h was required for an efficient effect against Campylobacter contaminated chicken skin. Using organic acids in the poultry production chain can reduce propagation of antibiotic multiresistant strains of Campylobacter.     

Diameter dependence of the apparent tensile modulus of hemp fibres: A morphological,structural or ultrastructural effect?

The aim of this paper is to investigate the origin of the diameter-dependence of Young’s modulus in hemp fibres. In view of the considerable experimental difficulties encountered when determining the 3D morphology of elementary fibres, the influence of the fibre morphology and size on the E-modulus is studied using a mathematical model. An approach based on the 3D elastic theory is used to construct a model of the fibre structure, and to predict its mechanical properties. We clearly show that the modulus is dependent on the size of the lumen and on the outer fibre diameter. This structural effect, induced by the cylindrical geometry, the multi-layered organisation, and the orientation of the cellulose microfibrils only partly explains the large, experimentally determined dispersion of apparent E-modulus, as a function of fibre diameter. Ultrastructural parameters, such as cellulose crystallinity and microfibril angles, are identified to be the main factors involved in this dependence.     

Treatment of landfill leachate using Fenton process and coagulation/flocculation

Coagulation/flocculation process, Fenton oxidation and combinations between them were studied, aiming to provide an efficient method for the treatment of partially stabilized leachates. Leachates were collected from a municipal landfill site, samples containing around 3800 mg/L COD, BOD₅/COD ratio about 0.11 and pH around 8. The sequence of stages implemented was: (a) coagulation/flocculation; (b) Fenton oxidation; (c) coagulation/flocculation followed by Fenton oxidation which resulted in a best COD removal (63.62%) and (d) Fenton oxidation followed by coagulation/flocculation.