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This article deals with the conditions of production of an area of knowledge linking feminism to cultural pluralism. It is based on a study of immigrant women identity strategies in the Sherbrooke area, an experience which involved women as researchers, interviewers, and participant-subjects. The article explains the principles and strategies of the feminist approach and the intercultural current which informed methodological choices. It also analyzes the difficulties and uncertainties which confront researchers engaged in the production of knowledge linking women and culture. The authors emphasize, as the "analyzer" of this process, the entire range of interactions produced within and between the three groups of women in the study.

This work describes a new approach to prediction of spatio-temporal evolution of mineral phosphorus in water bodies, particularly in Tiagba Lagoon Bay. Originality of this study lie on the use of artificial neural networks, principally multilayer perceptron, as modelling tool. Two approaches of spatio-temporal evolution of this nutrient were done: static evolution and dynamic evolutions. Data bases, formed by 3 966 and 4 627 data, served for static and dynamic modelling of this nutrient respectively. Weights of network connection are determined using Levenberg-Marquardt algorithm during execution of Multilayer Perceptron. Results obtained show that models 5-14-1 and 6-14-2 can predict to 70.30% and approximately 70% respectively for static and dynamic evolution of mineral phosphorus in this bay. These models, judged satisfactory, could be used for other studies led to rehabilitation and protection of this aquatic ecosystem for its long development.

Keywords: Phosphore, réseau de neurones artificiels, baie lagunaire de Tiagba, système Ébrié, Côte d'Ivoire, Phosphorus, artificial neural networks, multilayer perceptron, Tiagba Lagoon Bay, Ebrié system, Côte d'Ivoire

The town of Zinder has been confronted to a recurring drinking water scarcity since the 1920's. The causes of this problem are diversely interpreted according to the contexts and periods. This paper proposes a critical look at this situation for a better understanding of the problem. From an inventory of etiological narratives analyzed with the tools of the myth critique, on the one hand, hydrometric data and surveys, on the other hand, questions relating to the production and management of water, as well as people's pessimism as to a definitive solution to this problem are studied. Cross-analyses highlight three main explanations of the issue of water in Zinder. The popular imagination teaches that the lack of water finds its explanation in myths, which far from being mere cultural ornaments, are part of a perspective of legitimizing African people's power against the white-skinned invaders. In addition, drilling flow analysis reveals there is a low availability of water resource due to the crystalline subsoil, which has been very little altered. Thus, of the fifteen or so water drilling points sampled around the city, the average productivity is 0.57 m3∙h-1 (±0.47). Sixty percent of water drilling points have below the average flow; therefore, they are barely considered as productive. Finally, the volumes of water produced by pumping stations are always lower than the increasing needs of the population. To manage the shortage, the city's water management services have developed strategies such as the use of water access voucher, the limitation of connections and selective water cut. Despite the building of hydraulic infrastructures and the scientific arguments, the populations are less and less convinced about the definitive resolution of this problem due to the persistence of the shortage. Therefore, depending on the informants and the spatial scale of analysis, the shortage can be explained as a natural, economic, and socio-political issue.

Keywords: eau, mythe de l'eau, gestion de l'eau, Zinder, Sahel, water, water myth, water management, Zinder, Sahel

AbstractThe aim of this study was to conceive a strategy for the optimization of borehole depth in bedrock during hydraulic campaigns in the Ivory Coast. The methodology is based on data acquired in the Ivory Coast and it allows one to establish optimization equations for choosing the depth of the boreholes. It is founded upon statistical methods, notably Principal Component Analysis (PCA), to which multiple linear regressions are added to develop the needed equations. NCSS6.0 software was used for this study.The analysis showed that some borehole parameters, such as the drilling rate in the rock (Vas), the depth at which groundwater is first observed (Pae) and the number of times groundwater is observed (Nae), yield information about the existence of fractured aquifers. Therefore, they are useful in the development of the borehole depth optimization equations. The thickness of the rock drilled (Soc) is added, since this is the parameter to be optimized.The equation was tested on 171 boreholes in the Denguele region and on 43 other boreholes distributed among several geological formations within the Ivory Coast region. The result was positive for 90% of the all the geological formations tested. For a borehole depth of 9220 m, the application of the equation avoided an over-drilling of 728 m, i.e. an economy of 8%. This strategy thus allows a rational management of the budget for borehole drilling projects for village hydraulics, and favours the supply of water to a maximum number of people.

Keywords: socle, hydrogéologie, optimisation, profondeur, forages, Côte d'Ivoire, bedrock, hydrogeology, optimization, depth, boreholes, Ivory Coast

AbstractThe Haoud-Berkaoui region comprises three producing oil fields: Haoud-Berkaoui, Benkahla and Guellala, all located 100 km west of Hassi-Messaoud (Algéria). Oil is recovered from this heterogeneous medium sized layer by injecting water under pressure into the geological formations; the water is extracted from the Albien aquifer by 15 producing wells. To improve exploitation conditions and to increase injection capacities of this water, concentrics were installed within the producing wells to introduce anti-corrosion products. The life time of these facilities, initially predicted to be five years, has been reduced to only two years; important water leaks as well as deterioration of the wellheads have been noticed. The concentrics in the producing wells were in a very advanced state of corrosion, with apparent holes.Chemical analyses of water samples taken from several wells showed that their ion concentrations varied from 107 to 258 mg•L‑1 for calcium, 73 to 139 mg•L‑1 for magnesium, 24 to 36 mg•L‑1 for potassium, 282 to 304 mg•L‑1 for sodium, 459 to 648 mg•L‑1 for chlorides, while bicarbonate concentrations varied from 116  to 176 mg•L‑1. The water from these wells is generally hard, rich in sulphates, but poor in dissolved CO2 gas and lacking H2S and oxygen. The pH was neutral or slightly basic with values ranging between 7.02 and 7.58.A temperature gradient (∆T) was measured along the depth of the well, variable with depth, with a maximum gradient of 16 °C. The temperature gradient profile showed that ∆T was small at the surface of the well and then increased considerably at 584 m depth. For depths between 584 m and 984 m, ∆T was somewhat attenuated but remained high. It is in this zone that the concentric was most affected by corrosion.The corrosion of the concentric in an Albien medium under heat transfer was examined using electro-chemical techniques. The rate of corrosion increased sharply with increasing temperature, regardless of the water quality (i.e., treated with anti-bacterial or anti-corrosion agents, or not). These thermal effects are attributed to the acceleration of kinetic exchange reactions between the metal and the solution and are mainly linked to the energetic contribution associated with the heat flux crossing the concentric by conduction and convection.The efficiency of the anti-corrosion treatments was evaluated using the equation % E = 100 (Vcorr-V'corr)/Vcorr, where Vcorr and V'corr are the rates of corrosion with and without treatment, respectively. The best treatment efficiency of 30 % was obtained at a zero temperature gradient. The total absence of FeS eliminated the possibility of bacterial corrosion; the sulfato-reducing bacterium effect was eliminated by the bactericidal treatment.

Keywords: Albien, corrosion, simulation numérique, thermo-métrie, gradient de température, Albien, corrosion, numeric simulation, thermo-metry, temperature gradient

Modelling the hydrological behaviour of drainage basins is very important for solving problems related to the evaluation and optimal management of water resources. This is illustrated quantitatively in countries such as Algeria where water supply is a limiting factor. The principal aim of this paper was to explain the relationship between hydrological conditions and the availability of surface water. A model of rainfall-discharge was developed on a yearly scale, taking into account physical and climatic parameters. The application was carried out in northern Algeria where the total land surface is about 325 000 km2.The development of this model required a database, which was acquired during previous studies where maps of median rainfall and permeability as well as the digital elevation model were developed. In order to complete this database, the cartography of rainfall for the years for which we have discharge data was carried out using a methodology entitled "mapping standardized rainfall". To estimate and map annual rainfall, the kriging method was used. Two problems were encountered:- The presence of a drift highly altered the variogram and made it very difficult to infer a sub- structure function;- The variogram is significant only if the hypothesis of ergodicity is valid, which was not easy to assume for any given year.In order to resolve these difficulties, a homogeneous random and secondary stationary order function (same mean at all points and same covariance function) must be calculated. A previous study by ANRH (1993) allowed us to know the statistical parameters of the distribution at each point. These parameters were mapped, taking into consideration the topographical relief and distance to the sea. For every year and at each rainfall measure point, the standardized rainfall could be deduced. The correlogram gave information about the spatial variability of the phenomenon and its range, and subsequently the standardized rainfall was then interpolated. Annual rainfall was calculated by combining the grids of the means, the variances and the centered reduced rainfall (TOUAZI and LABORDE, 2000). Thus, the data of 467 rainfall gauges were used in order to create maps of the yearly isohyets.The rainfall-discharge relationship on an annual scale was based on 50 hydrometric stations distributed throughout the study area. The methodology used was derived from the production function of the S.C.S (Soil Conservation Service). This production function was part of modelling, which transformed total rainfall to net rainfall. This method was very representative of the natural hydrological processes. Indeed, it takes into account rainfall and the maximum infiltration capacity (S), which depends on the nature of the soil (lithology), vegetation and soil moisture content. In the current study, the basin surface and a regional parameter (a) were introduced in order to calibrate the model. This production function was implemented by supplying different values for the parameter (S). The values (n+1) were obtained by increasing the previous value (n) by 10 %. We evaluated the different values of (S) in the same way to obtain the last value (i). We calculated for these different values of the parameter (S) the square of the difference between the measured and estimated discharges for each year by measuring the discharge at different stations. For each station, we calculated the sum of these values for all the years and we retained the value of (S) that gave the minimal value. The results demonstrated that the values of (S) obtained were not significant because they tend to the infinite. For this reason, (S) was considered as a constant. In order to improve the model, we repeated the same operation, but instead of (S), we used the parameter (a) and performed the same calculation. After calibration of the model the results gave a coefficient of determination of 0.75, which means that 75 % of the variance was explained by the mean rainfall, the surface and the parameter (a).To explain the parameter (a), we calculated the correlation between its value at each station with the corresponding geology. This latter variable was characterized by the average storage capacity, which corresponds to the weighted average of the surfaces of the basin assigned to each permeability category (TOUAZI, 2001). The results demonstrated a coefficient of determination of 0.1. The correlation with the topographical relief was not necessary because it was taken into account in the cartography of the rainfall. We then proceeded to the cartography of the parameter (a). The results demonstrated an east-west gradient that was constant and a north-south gradient that decreased from north to south. With the digital elevation model, we used a geographical information system to deduce the slopes. For each basin, the average slope was calculated by taking the average of the values of the slopes of all the pixels that constituted the individual basin. The correlation between slopes and corresponding values of the parameter (a) gave a coefficient of correlation of 0.6.The results obtained by this model after calibration gave a coefficient of determination of 0.75, which means that 75% of the variance was explained by the mean rainfall, the surface and a coefficient (a), which corresponds to the average slope of the drainage basins.

Keywords: Algérie du Nord, bassins versants, cartographie automatique, débits, krigeage, système d'information géographique, fonction de production du SCS, Northern Algeria, soil conservation service production function, discharge, drainage basin, automatic mapping, kriging, geographical information system

AbstractThis study concerns the impact of attending an ethnoreligious school on the ability to master French for Armenian, Muslim and Jewish students registered in French schools, in Secondary Four and Five. It builds on the research of Sercia (2004) that focused on the social integration of immigrant students. The measure of aptitude in French is composed of twelve items that cover the attitudes, behaviours, preferences and intentions of students. The analysis of data shows significant differences between the three groups on one or more of the variables, which leads the author to trace a unique portrait of each group that accounts for its particular situation.

Keywords: Français, école ethnoreligieuse, immigration, intégration, Québec, French, ethnoreligious school, immigration, integration, Quebec

Abstract In painting, the canonical scene of the Annunciation was, for a period of two or three hundred years, a challenge to mise en scène : how to join the heavenly and the earthly ? This article inquires into how certain films have taken up some of the solutions that were found for this “annunciative model.” The particular focus is on films which, without quoting any particular painting literally, show signs of a “migration” of painting into the cinema through their concern for creating a representational art by re-examining from scratch the question of symbolism, without relying on more-or-less fantastic fictional beings. Thus for certain filmmakers, “creating Annunciations” has not meant a desire to ennoble their films culturally, but is rather the manifestation of an attempt to wield forms, themes and figures as an ensemble. In other words, to produce, not the gesture of a painter, but the gesture of an auteur.