A study of depth/texture bit-rate allocation in multi-view video plus depth compression

Multi-view video plus depth (MVD) data offer a reliable representation of three-dimensional (3D) scenes for 3D video applications. This is a huge amount of data whose compression is an important challenge for researchers at the current time. Consisting of texture and depth video sequences, the question of the relationship between these two types of data regarding bit-rate allocation often raises. This paper questions the required ratio between texture and depth when encoding MVD data. In particular, the paper investigates the elements impacting on the best bit-rate ratio between depth and color: total bit-rate budget, input data features, encoding strategy, and assessed view.     

Investigation of damp heat effects on glass properties for photovoltaic applications

Damp heat test was performed on soda-lime glass to characterise functional properties of glass in photovoltaic applications and define the ageing mechanism. In addition to the optical property measurements, SEM-EDX, XPS and FTIR analyses were carried out. The damp heat exposed samples presented an increased transmittance in UV, visible and near-IR ranges namely within (1900–2100?nm). The results were explained by hydration of glass network with heat. An ageing mechanism based on glass corrosion theories is discussed. Molecular water adsorption involves a leaching process of network modifier cations and especially sodium ions. Hydrolysis also occurs in silica network by reacting free molecular water. This phenomenon enhances concentration of hydroxyl groups in glass highlighted by FTIR measurements and promotes formation of silanol groups. A tin side dependence on sodium leaching which acts as a passivating barrier for ionic transport is highlighted which may be taken into consideration for photovoltaic module design.     

An Imbricate Finite Element Method (I-FEM) using full, reduced, and smoothed integration

A method to design finite elements that imbricate with each other while being assembled, denoted as imbricate finite element method, is proposed to improve the smoothness and the accuracy of the approximation based upon low order elements. Although these imbricate elements rely on triangular meshes, the approximation stems from the shape functions of bilinear quadrilateral elements. These elements satisfy the standard requirements of the finite element method: continuity, delta function property, and partition of unity. The convergence of the proposed approximation is investigated by means of two numerical benchmark problems comparing three different schemes for the numerical integration including a cell-based smoothed FEM based on a quadratic shape of the elements edges. The method is compared to related existing methods.     

Design of experiment techniques for fuel cell characterisation and development

Designs of Experiments (DoE) can be of immediate relevance for various research works conducted in the Fuel Cell (FC) area. DoE techniques allow efficient test definitions for rapid conceptions and well-organised characterisations of FC materials and components, individual cells, stacks or even complete generators. In the DoE method, some statistic-based models can be proposed in pre-stages of physical models. The statistical/numerical relations are used to predict the behaviour of the investigated systems as a function of various operating parameters. Some control strategies can also be developed to optimise relevant criteria like FC voltage, fuel consumption, and maximal electrical power or stack lifetime.     

Nuclear decontamination of cementitious materials by electrokinetics: An experimental study

The objective of this paper is to evaluate the efficiency of an electrokinetic method of radionuclide removal from a cement-based material. This work is a two-part process. In the first part, a sample of mortar was uniformly contaminated for use as a reference. In order to ensure a uniform contamination, the ingress of the radioelement (cesium) was controlled by an external electrical field. The second part of this work concerns the removal of cesium from the contaminated mortar samples. This second, decontamination, phase was driven by the same electrical field. No electroosmosis was detected. Both phases were characterized by analyses of cesium and calcium concentrations in cathodic and anodic solutions, and by measurements of cesium content in the samples at the end of each phase. In addition to the electrical current, pH, and conductivity were measured during the experiments. Finally, the efficiency of the electrokinetic method was described in terms of decontamination factor, leading to promising results.     

Kinetics of the NO + H2 reaction over supported noble metal based catalysts: Support effect on their adsorption properties

This paper reports a kinetic investigation of the global reduction of NO by H₂ which has been considered as a probe reaction for characterising the adsorption properties of supported palladium based catalysts. A particular attention has been paid towards the influence of the support on the catalytic properties of Pd, particularly towards the production of undesirable by-products such as nitrous oxide (N₂O) and ammonia (NH₃). It has been found that the kinetics of the overall NO + H₂ reaction on Pd/Al₂O₃ can be correctly depicted according to a Langmuir–Hinshelwood mechanism involving the dissociation of nitrosyl species assisted by chemisorbed hydrogen atoms. On the other hand, Pd/LaCoO₃ exhibits a different kinetic behaviour towards the adsorption of hydrogen depending on the pre-activation thermal treatment. In that case, different mechanisms may occur.     

Analysis of flame surface density measurements in turbulent premixed combustion

In premixed turbulent combustion, reaction rates can be estimated from the flame surface density. This parameter, which measures the mean flame surface area available per unit volume, may be obtained from algebraic expressions or by solving a transport equation. In this study, detailed measurements were performed on a Bunsen-type burner fed with methane/air mixtures in order to determine the local flame surface density experimentally. This burner, located in a high-pressure combustion chamber, allows investigation of turbulent premixed flames under various flow, mixture, and pressure conditions. In the present work, equivalence ratio was varied from 0.6 to 0.8 and pressure from 0.1 to 0.9 MPa. Flame front visualizations by Mie scattering laser tomography are used to obtain experimental data on the instantaneous flame front dynamics. The exact equation given by Pope is used to obtain flame surface density maps for different flame conditions. Some assumptions are made in order to access three-dimensional information from our two-dimensional experiments. Two different methodologies are proposed and tested in term of global mass balance (what enters compared to what is burned). The detailed experimental flame surface data provided for the first time in this work should progressively allow improvement of turbulent premixed flame modeling approaches.