18 research outputs found
UTILISATION D’UN MODELE HYBRIDE BASE SUR LA RLMS ET LES RNA-PMC POUR LA PREDICTION DES PARAMETRES INDICATEURS DE LA QUALITE DES EAUX SOUTERRAINES CAS DE LA NAPPE DE SOUSS-MASSA- MAROC
This work describes a new approach to the prediction of the parameters (microbiological, physical-chemical) groundwater quality indicators in the water table of Souss-Massa Morocco. The originality of this work lies in the application of a hybrid model based on the Stepwise Multiple Linear Regression and Neural Networks Multilayer Perceptron type. During the first stage, conventional statistical models namely the Stepwise Multiple Linear Regression was applied to a database that consists of eleven vectors as input vectors of the model and three vectors as the model output vectors in order to optimize the explanatory variables. In a second step, the optimized data base in the first step was used to construct a non recurring multi-layer network, the weights of the network connections are determined using the gradient back propagation algorithm. The data used as a database (learning, testing and validation) of the hybrid model are those relating to the analysis of 52 groundwater samples collected at several stations distributed in space and in time, of the groundwater Souss-Massa Morocco. The dependent variables (to explain or predict), which are three in number, are the Electrical Conductivity EC, the amount of Fecal Coliforms CF and Organic Matter MO
UTILISATION D’UN MODELE HYBRIDE BASE SUR LA RLMS ET LES RNA-PMC POUR LA PREDICTION DES PARAMETRES INDICATEURS DE LA QUALITE DES EAUX SOUTERRAINES CAS DE LA NAPPE DE SOUSS-MASSA- MAROC
This work describes a new approach to the prediction of the parameters (microbiological, physical-chemical) groundwater quality indicators in the water table of Souss-Massa Morocco. The originality of this work lies in the application of a hybrid model based on the Stepwise Multiple Linear Regression and Neural Networks Multilayer Perceptron type. During the first stage, conventional statistical models namely the Stepwise Multiple Linear Regression was applied to a database that consists of eleven vectors as input vectors of the model and three vectors as the model output vectors in order to optimize the explanatory variables. In a second step, the optimized data base in the first step was used to construct a non recurring multi-layer network, the weights of the network connections are determined using the gradient back propagation algorithm. The data used as a database (learning, testing and validation) of the hybrid model are those relating to the analysis of 52 groundwater samples collected at several stations distributed in space and in time, of the groundwater Souss-Massa Morocco. The dependent variables (to explain or predict), which are three in number, are the Electrical Conductivity EC, the amount of Fecal Coliforms CF and Organic Matter MO
Air Quality Study in Urban Centers: Case Study of Ouagadougou, Burkina Faso
In this work, a study on air quality in the city of Ouagadougou (Burkina Faso) was carried out. The concentration levels of NO2, SO2, BTEX and PM10 in the city have been quantified. The results show that NO2 concentrations (range from 22 to 27 μg m-3 on average) in the city remain below the limit set by the WHO standard, except for downtown where values often exceed this standard. The average concentrations of SO2 (range from 0.5 to 10.5 μg m-3) remain low in general throughout the city. The concentrations of BTEX (e.g. benzene: 27.9 μg m-3) are high in the city. PM10 concentrations are very high in the city in general; they exceed the limit set by the WHO standard by a factor of 3 to 4. These PM10 are mostly composed of dust from the desert and the re-suspension of dust particles related to vehicles traffic on unpaved roads. Two daily peaks for PM10 are observed at heavy traffic hours. Finally, the study showed that the values of PM10 concentrations observed are in the same order of magnitude of those generally observed in the Sahelian region (range from 119 to 227μg m-3)
Résilience entre les occupations humaines préhistoriques et les dépôts de travertins au Maroc.
International audienc
Résilience entre les occupations humaines préhistoriques et les dépôts de travertins au Maroc.
International audienc