Documents found
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131.More information
Keywords: éducation à l'image, cinéma, programmes éducatifs, France, témoignage
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132.More information
Of the many causes of distributed water quality deterioration, biological phenomena are undoubtedly the subject of the most study, and are also the most closely monitored because of short-term public health risks. Although high heterotrophic bacterial counts do not necessary constitute a health risk, they are the sign that a particular network is subject to biological disorders which can protect pathogenic species. What is more, the evolution of the bacterial biomass in the network also affects other aspects of distributed water quality, such as tastes and odours, the development macro-invertebrates, the appearance of colour and turbidity and the appearance of biocorrosion phenomena. Qualitative management of distribution networks is therefore to ensure that the quality of the product is kept as constant as possible up to the farthest points of the distribution. With this in mind, it is essential to understand, describe and model the various phenomena which lead to the evolution of water quality during distribution. Mathematical modelling is necessary in order to take ail parameters into account in view of the complexity of the different phenomena involved. A determinist type modelling was developed to predict bacterial variations (viable and total bacteria) during distribution. The model takes into account: - the fate of available nutrients consumed for the growth of suspended and fixed bacteria, - the influence of temperature on bacterial dynamics, - the natural mortality of bacteria by senescence and grazing, - the mortality resulting from the presence of chlorine disinfectant, with a differentiation between the action on free et fixed bacteria,- the impact of different forms of chlorine in water (HCIO/CIO-) dépending on pH on the mortality rate,- the deposition of suspended bacteria and the detachment of fixed bacteria,- the chlorine decay kinetics onder the influence of temperature, hydraulics and pipe materials.The modelling of the fixed biomass as a layer uniformly distributed over the pipe surface, expressed as an équivalent thickness of carbon, has been adopted. By this way, a differentiation between the mathematical expression of the free and that of the fixed biomass was made in the model. This mean it is possible to distinguish between phenomena depending on their locations: reactions in solution, réaction at the water/biofilm surface interface and within the biofiJm.This model proposes also an original approach for chlorine bactericidal action on suspended and fixed biomass. To model the action of chlorine on the fixed biomass and its stronger résistance compared with the free biomass, the diffusion of the chlorine through the boundary layer and the biofilm has been taken into account. This calculation of the average penetration depth of the chlorine front into the biofilm enables the identification of two layers: a chlorinated layer and a layer not attained by the chlorine which provides a material indication of the better resistance of the fixed biomass.As detachment is a key phenomenon in the modelling of bacterial dynamics in distribution Systems, the influence of different formulas of detachment kinetics on the mathematical expression of model variables were determined by soiving model equations.The model has been interfaced with PICCOLO software, the SAFEGE hydraulic calculation model. It is constructed by using hydraulic results previously generated by PICCOLO and a numerical scheme to predict bacterial count at each node and on each link of a network. Installed on a PC type computer, the model uses the graphic interface of PICCOLO and provides an effective and easy way to visualise on a computer screen water quality variations in the network, using a colour code for bacterial count, nutrient concentration and chlorine residual.The first model calibration was done using data from our pipe loop pilot under various operating conditions. The model has been also used to simulate a variety of distribution Systems of different sizes and levels of details and a validation of the model has been carried out by means of measurement campaigns on different distribution Systems.Animating and visualising variations of bacteria counts in distribution system is an unique approach to study the changes in water quality. This tool is helpful to propose strategies for the management of distribution Systems and treatment plants and define the different zones of bacterial regrowth in relation with hydraulic conditions.
Keywords: croissance bactérienne, modélisation, réseaux de distribution, logiciel, bio-film, eau potable, bacterial regrowth, modelling, distribution systems, software, biofilm, drinking water
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133.More information
Noting the focus of the French tradition in discourse analysis on textometric softwares, the author attempts to model the fundamental processes underlying the analyst-text interaction distinguishing the modes, operations, dimensions, granularity, contextuality and temporalities of the process, and so, with or without recourse to computer processing. Based on this modeling, textometric softwares show that the assistance of the researcher is often a matter of bringing to display, through queries-retrieval, automatic assignments and representations, textual and extra-textual data, but rarely a matter of assisting the researcher in his working of the text (e.g. customized annotations, multiplicity of reading layers, corpus evolution) to produce and construct meaning by his or her analysis traces in an integrated environment. The origins of this trend are discussed as well as directions for future developments.
Keywords: Analyse de texte assistée par ordinateur, Analyse de discours (tradition française), Annotation, interaction analyste-texte, logiciels textométriques, niveaux d'analyses, Computer assisted text analysis, Discourse Analysis (French tradition), Annotation, Analyst-text interaction, Textometric softwares, Levels of analysis, análisis de texto asistido por ordenador, análisis de discurso (tradición francesa), anotación, interacción analista-texto, softwares textométrico, niveles de análisis
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137.More information
Massively multiplayer online game, virtual worlds where hundreds of thousands of players compete through epic quests, are becoming increasingly popular. Because of their popularity and their influence, they bring a range of major social changes, especially in terms of deviant behavior, and criminal offenders. In this paper, we will see how we can understand those universe and how deviant, delinquent and criminal acts are conducted through them.
Keywords: Jeux vidéo, délinquance, Internet, cyberespace, criminalité informatique, cybercriminalité, hackers, Video Games, Delinquancy, Internet, Cyberspace, Computer crime, Cybercriminality, Hackers, Juegos de video, delincuencia, Internet, ciberespacio, criminalidad informática, cibercriminalidad, hackers
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138.More information
Survey of computer use in physic teaching. - During the last ten years, several means of operating computers have been in use : tutorial teaching, training exercices, experimental measure processing, simulation, numeric and graphic exploration, laboratory instrumentation. There has been a large trend in the role of the machine from the function of sharing teaching with the teacher during an experimental phase to that of tool for exploration and experiment since micro computer development.
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