Introducing 3D Cinematography [Guest editors' introduction]

Recent developments in computer vision and computer graphics, especially in such areas as multiple-view geometry and image-based rendering, are making it possible to generate 3D models of dynamic scenes from multiple cameras at video frame rates. The authors call this process 3D cinematography since it extends traditional cinematography from 2D (images) to 3D (solid objects that we can render with photorealistic textures from arbitrary viewpoints) at the same frame rate. The authors provide an overview of the field as well as introduce the articles in their Special Section on 3D Cinema.     

Effect of Combined Grinding–Burnishing Process on Surface Integrity,Tribological, and Corrosion Performance of Laser-Clad Stellite 21 Alloys

Herein, the influence of the grinding–burnishing on surface integrity, mechanical properties, and corrosion performance of Stellite 21 alloys coating deposited by laser cladding is investigated. The as-clad specimens are first ground followed by further modification by ball burnishing at forces of 424 N and 509 N. Results show that the grinding–burnishing enhances surface finish by lowering R_a from 2.6 to 0.73 μm and R_z from 13 to 4.9 μm, respectively. Surface porosity is found to decrease from 3.8% to 0.9%. Hardness is increased from 609 HV to 702 HV, with a surface alteration as deep as 250 μm, while wear resistance increases by reducing worn volume from 4.15 to 2.95 mm³. Because of high hardness, the grinding–burnishing increases impact resistance by lowering indent depth by 20%. Grains flatten and surface undulations are remarkably reduced due to burnishing. Finally, grinding–burnishing at 509 N improves the corrosion resistance by increasing positive corrosion potential from −0.41 to −0.14 V and lowering corrosion current density from 6.34 × 10⁻⁴ A cm⁻² to 2.19 × 10⁻⁵ A cm⁻², as compared to grinding. This synergistic grinding–burnishing can be a plausible post-treatment route for the laser-clad alloys.     

Oxidation/corrosion of BN-based coatings as prospective interphases for SiC/SiC composites

The ceramic matrix composites envisaged as structural parts in the hot section of aircraft engines consist of SiC-based fibres and matrices with a BN interphase coating between them. To control their service life, the oxidation/corrosion behaviour of these materials must be determined. For this purpose, samples of different geometries were prepared by chemical vapour deposition and thermally subjected to wet air. The behaviour of BN alone depends on its crystallization degree, structural homogeneity and the considered direction in the coating. In the case of a thin layer of pure BN of interphase type, recession is significantly reduced at 800 °C by the formation of a sealing borosilicate phase in the confined space surrounded by SiC. At 1000 °C, the protection is no longer sufficient and a steady recession remains. The presence of aluminium added to BN improves protection at 1000 °C due to the formation of alumina combined with borosilicate.     

Light propagation in multilayered scattering media beyond the diffusive regime

We describe a method to solve the radiative transfer equation (RTE) in multilayered geometry with index mismatch and demonstrate its potential for modeling light propagation in biological systems. The method is compared to Monte Carlo simulations with high accuracy but is much more efficient in terms of computer time. We illustrate the potential of the method by studying a multilayered system containing a weakly scattering layer surrounded by highly scattering layers, with anisotropic scattering and index mismatched interfaces. The calculation of directional transmitted fluxes has shown that the RTE method can be used to calculate relevant quantities in realistic systems in the presence of non-diffusive behavior.     

Design considerations of Miller oscillators for high-sensitivity QCM sensors in damping media

In this paper, a new contribution to the design of quartz crystal oscillators for high-sensitivity microbalance sensors used in liquid media is presented. The oscillation condition for a Miller configuration was studied to work in a wide dynamic range of the resonator losses. The equations relating the values of the active and passive components with the maximum supported damping and mass were obtained. Also, the conditions to obtain a stable frequency according to the resonator damping (R(Q)), the static capacity (Cp) and the filter frequency (f(F)) were found. Under these conditions, the circuit oscillation frequency will be proportional to the resonant series frequency and does not depend on the previous parameters (R(Q), f(F), and Cp). If these conditions cannot be satisfied, the expression of the oscillation frequency is given and the discrimination of these effects is obtained through resonator frequency measurements.     

Magnetic resonance imaging study of complex flow of viscoelastic fluids

NMR imaging techniques have been applied to investigate complex fluid dynamics in pipes and in annular flow conditions. In this application, aimed to simulate drilling and production operations, two lines have been set up to reproduce, at small laboratory scale, respectively, a pipe flow and an annular flow that are typical flow geometries in oilfield wells during drilling. NMR imaging measurements have been performed inside a horizontal‐bore magnet with a fluid flow assured in a velocity range of 10–100 cm s^?1. The studies were dedicated to investigate the different flow regimes associated to circulating viscous polymer solutions applied in drilling mud formulations. Early transitions from laminar to turbulent regime were observed at very low Reynolds number (in a range between 300 and 500, to be compared with the theoretical transition value greater than 2100). © 2010 American Institute of Chemical Engineers AIChE J, 2011     

Characterization of Listeria monocytogenes strains isolated from Gorgonzola cheese rinds

Listeria monocytogenes is a foodborne pathogen frequently present in ripened soft cheeses. Forty-three strains of L. monocytogenes isolated from the rind of ripened Gorgonzola cheeses produced in 24 different dairy plants were characterized by biotyping, serotyping, and molecular typing. Biotyping was performed by studying two phenotypes closely associated with virulence, such as hemolytic and phospholipase C activities. Traditional typing techniques did not allow a discrimination among the 43 strains studied. All strains showed a good hemolytic activity on blood agar, and only slight differences were observed when titration of hemolytic activity of culture supernatants was performed. Also phospholipase activities were quite similar for all the strains. Concerning serotyping, all strains belonged to serotype 1/2a. The molecular characterization was performed by RAPD-PCR. Combined cluster analysis following PCR amplification experiments allowed to group L. monocytogenes strains into few distinguishable profiles. At a level of similarity of 80%, the 43 strains were grouped into only 5 composite profile groups. Although isolated in 24 different plants, the presence of a few closely related strains demonstrated a possible relationship between these cheese isolates; a special ability of these strains to adapt to Gorgonzola cheese processing environment could be suggested.     

Controlled Inline Fluid Separation Based on Smart Process Tomography Sensors

Today's mechanical fluid separators in industry are mostly operated without any control to maintain efficient separation for varying inlet conditions. Controlling inline fluid separators, on the other hand, is challenging since the process is very fast and measurements in the multiphase stream are difficult as conventional sensors typically fail here. With recent improvement of process tomography sensors and increased processing power of smart computers, such sensors can now be potentially used in inline fluid separation. Concepts for tomography-controlled inline fluid separation were developed, comprising electrical tomography and wire-mesh sensors, fast and massive data processing and appropriate process control strategy. Solutions and ideas presented in this paper base on process models derived from theoretical investigation, numerical simulations and analysis of experimental data.     

Handling effective communication to support awareness in rescue operations

Efficient rescue operations require a high level of situation awareness amongst decision‐makers and first responders for the purpose of achieving operations successfully and reducing losses. Moreover, a common operational picture between involved actors is required in order to support decision‐making. Therefore, different organisations and agencies have to collaborate, cooperate, and coordinate their actions with each other. Hence, effective interactions and communications between participants are vital to fulfil these essential needs. However, emergency actors still lack backing to exchange information effectively and ensure a common operational picture in order to reach shared situational awareness. For this reason, we aim to develop and implement Rescue MODES, a communication system oriented to support situation awareness amongst French emergency actors in rescue operations. In this paper, we examine and analyse actors’ activities and interactions, so that the system will be based on the real needs of actors. We start by studying and modelling the communications, interactions, and information flow. This modelling is based on an application ontology. Then, we define requirements for good communication in these operations and present some existing systems in France and how each system responds to these requirements.