Mathematical modeling and numerical simulation of a bioreactor landfill using Feel++

In this paper, we propose a mathematical model to describe the functioning of a bioreactor landfill, that is a waste management facility in which biodegradable waste is used to generate methane. The simulation of a bioreactor landfill is a very complex multiphysics problem in which bacteria catalyze a chemical reaction that starting from organic carbon leads to the production of methane, carbon dioxide and water. The resulting model features a heat equation coupled with a non-linear reaction equation describing the chemical phenomena under analysis and several advection and advection-diffusion equations modeling multiphase flows inside a porous environment representing the biodegradable waste. A framework for the approximation of the model is implemented using Feel++, a C++ open-source library to solve Partial Differential Equations. Some heuristic considerations on the quantitative values of the parameters in the model are discussed and preliminary numerical simulations are presented

Infinite non-causality in active cancellation of random noise

Active cancellation of broadband random noise requires the detection of the incoming noise with some time advance. In an duct for example this advance must be larger than the delays in the secondary path from the control source to the error sensor. In this paper it is shown that, in some cases, the advance required for perfect noise cancellation is theoretically infinite because the inverse of the secondary path, which is required for control, can include an infinite non-causal response. This is shown to be the result of two mechanisms: in the single-channel case (one control source and one error sensor), this can arise because of strong echoes in the control path. In the multi-channel case this can arise even in free field simply because of an unfortunate placing of sensors and actuators. In the present paper optimal feedforward control is derived through analytical and numerical computations, in the time and frequency domains. It is shown that, in practice, the advance required for significant noise attenuation can be much larger than the secondary path delays. Practical rules are also suggested in order to prevent infinite non-causality from appearing

Schwinger terms in gravitation in two dimensions as a consequence of the gravitational anomaly

We compute the Schwinger term in the gravitational constraints in two dimensions, starting from the path integral in Hamiltonian form and the Einstein anomaly.Comment: 8 pages, Latex, additional reference

GIS interfaced OECD/PIARC QRA model for road transportation of hazardous goods

International audienceWithin the framework of a research project carried out for both the OECD and the PIARC, INERIS developed a Quantitative Risk Assessment Model (QRA model) for the transport of Hazardous Goods on roads including tunnel sections. This work was also carried out with the collaboration of WS-Atkins (UK) and the University of Waterloo (Canada). INERIS, which was the leading developer of this original model, launched a new research project in order to facilitate the generation of data necessary for a given risk study. A new version of the model is in development. These new developments have been funded by the French Ministry of Ecology and Sustainable Growth and the French Ministry of Equipment, Transport and Buildings, Tourism and the Sea. These new developments have been processed in order to enhance the user-interface performance of the original models (QRAM 3.20 and 3.60) and to extend the QRAM capacities to the study of longer routes. These objectives has been reached by the introduction of a linked Geographical Information System (GIS). In between the original model (QRA v3.20) has been used for the application of the French regulation (circular 2000-82, 30th november 2000). Up to now approximately twenty tunnel safety cases have been studied in order to choose the lowest risky route between the open air route and the tunnel one. Doing that the risk level for the road transportation of hazardous goods has been reduced. In order to have in one hand a global view of the various developments of the QRAM and in an other hand to linked these models to the European regulation framework the present paper deals with the following topics : The present regulation for the transport of dangerous goods by road in Europe, The methodology governing the QRAM, The lessons from the French application of the QRAM, The new developments for a GIS interfaced QRAM, The application of the QRAM at European and International level

The highly polymorphic CYP6M7 cytochrome P450 gene partners with the directionally selected CYP6P9a and CYP6P9b genes to expand the pyrethroid resistance front in the malaria vector Anopheles funestus in Africa

Background: Pyrethroid resistance in the major malaria vector Anopheles funestus is rapidly expanding across Southern Africa. It remains unknown whether this resistance has a unique origin with the same molecular basis or is multifactorial. Knowledge of the origin, mechanisms and evolution of resistance are crucial to designing successful resistance management strategies. Results: Here, we established the resistance profile of a Zambian An. funestus population at the northern range of the resistance front. Similar to other Southern African populations, Zambian An. funestus mosquitoes are resistant to pyrethroids and carbamate, but in contrast to populations in Mozambique and Malawi, these insects are also DDT resistant. Genome-wide microarray-based transcriptional profiling and qRT-PCR revealed that the cytochrome P450 gene CYP6M7 is responsible for extending pyrethroid resistance northwards. Indeed, CYP6M7 is more over-expressed in Zambia [fold-change (FC) 37.7; 13.2 for qRT-PCR] than CYP6P9a (FC15.6; 8.9 for qRT-PCR) and CYP6P9b (FC11.9; 6.5 for qRT-PCR), whereas CYP6P9a and CYP6P9b are more highly over-expressed in Malawi and Mozambique. Transgenic expression of CYP6M7 in Drosophila melanogaster coupled with in vitro assays using recombinant enzymes and assessments of kinetic properties demonstrated that CYP6M7 is as efficient as CYP6P9a and CYP6P9b in conferring pyrethroid resistance. Polymorphism patterns demonstrate that these genes are under contrasting selection forces: the exceptionally diverse CYP6M7 likely evolves neutrally, whereas CYP6P9a and CYP6P9b are directionally selected. The higher variability of CYP6P9a and CYP6P9b observed in Zambia supports their lesser role in resistance in this country. Conclusion: Pyrethroid resistance in Southern Africa probably has multiple origins under different evolutionary forces, which may necessitate the design of different resistance management strategies

Characterization of Information Automation on the Flight Deck

This paper summarizes the results of analyses to identify characteristics of flight deck information automation systems which can lead to potential human factors issues. Information automation systems are responsible for the collection, processing, analysis, and presentation of information to the flightcrew. Information automation systems can pose human factors issues and challenges particular to this type of automation. This paper presents a formal definition of information automation and identifies characteristics and associated human factors issues in the domain of aircraft flight deck systems. A method was developed to identify a set of consistent and independent characteristics of information automation. Characteristics, a set of properties or attributes which describe its operation or behavior, can be used to identify and assess potential human factors issues. This effort lays the groundwork for providing data to support the development of recommendations specific to different characteristics of information automation

Spontaneous CP Violation in a SUSY Model with a complex CKM

It is pointed out that the recent measurement of the angle $\gamma$ of the unitarity triangle, providing irrefutable evidence for a complex Cabibbo-Kobayashi-Maskawa (CKM) matrix, presents a great challenge for supersymmetric models with spontaneous CP violation. We construct a new minimal extension of the minimal supersymmetric standard model (MSSM), with spontaneous CP breaking, which leads to a complex CKM matrix, thus conforming to present experimental data. This is achieved through the introduction of two singlet chiral superfields and a vector-like quark chiral superfield which mixes with the standard quarks. A $Z_3$ symmetry is introduced in order to have a potential solution to the strong CP problem.Comment: 12 pages. Uses the elsart.cls LaTeX class. Minor corrections and references adde

Translation and validation of the German version of the Mother-Generated Index and its application during the postnatal period.

the Mother-Generated Index (MGI) is a validated tool to assess postnatal quality of life. It is usually administered several weeks or months after birth and correlates with indices of post partum mood states and physical complaints. The instrument had not been translated into German before or validated for use among German-speaking women, nor have the results of the tool been assessed specifically for the administration directly after birth. This paper aims to describe the systematic translation process of the MGI into German and to assess the convergent validity of the German version of the instrument directly after birth and seven weeks post partum