11 research outputs found
Geology, mineralogy, geochemistry and deposit model of iron and manganese in Bouarfa mine, Eastern High Atlas, Morocco
No full textThe Bouarfa Iron and Manganese Deposits are contained in the Sinemurian carbonate formations in the eastern High Atlas. It is a large deposit which has allowed the exploitation of more than 1.5 million tons of manganese and which still contains millions of tons of reserves. The mapping carried out shows the extension of the mineralization with oxides and hydroxides of Mn and Fe. The definition of types of mineralization shows that they are essentially stratiform deposits with some bodies and veins in the fault zones. The result of the mineralogical identification and geochemical analyses shows that it is a sedimentary deposit resulting from at least two mineralizing events with a high Fe-Mn content during the installation of the Sinemurian shallow carbonate platform. This is an environment of rapid oxidation and relatively sufficient sulphide inputs under redox conditions
Flow Separation Control over a Wing-Flap Model: Analysis of flap leading edge applications
No full textNowadays, the development of multi-element airfoils show a progression towards a “circular arc” to attain a maximum lift force. The improvement of the high lift performance of specifically a wing-flap combination is an ongoing research at Delft University of Technology. Generally, a higher lift force can be created by deflecting the flap to higher angles. The higher this angle, the larger the curvature the flow has to follow. Consequently the flap becomes dominated by separated flow and a big part of the lift force will be lost. To overcome this lift loss due to flow separation additional flow control techniques become essential. Hence, within the scope of lift improvement, the effect of flap leading edge applications is investigated for a wing-flap model at critical flight conditions i.e. high flap deflection angle of 45◦ and Re = 1.7 · 106 (42m/s).Aerospace Engineering | Aerodynamics and Wind Energ
Habitants des bidonvilles et revendications de droits de citoyenneté au Maroc
No full textDe nombreux travaux ont montré que, dans les bidonvilles marocains, les droits de citoyenneté occupent une place de choix dans les pratiques et discours des habitants. À partir d’une enquête menée dans des bidonvilles de deux régions différentes – Nzala Raddaya (la région de Fès-Meknès) et Douar Laamour (la région de Casablanca-Settat) –, j’ai plus particulièrement focalisé mon attention sur l’importance que revêtent les documents administratifs accréditant les habitants de leur statut de bidonvillois ou permettant de bénéficier des opérations de recasement dans le cadre de la politique de lutte contre les bidonvilles. Ces documents, depuis l’accès aux services publics jusqu’à l’opportunité d’être relogé, sont au cœur des stratégies mobilisées aussi bien par les habitants des bidonvilles que par les acteurs publics qui les délivrent ou les réclamentScholarship has shown that, in moroccan shantytowns, the rights of citizenship hold an important place in practices and narratives of the inhabitants. Based on fieldwork conducted in shantytowns in different regions (Nzala Raddaya – in the Fes-Meknes region) and Douar Laamour (in the Casablanca-Settat region), the author paid special attention to the importance taken on by administrative documents which vouch for the status of shantytown dwellers. As such, these documents enable their holders to benefit from resettlements policies in the aim of eradicating shantytowns. The materiality of these documents, which grant access to public services through to the possibility of resettlement, are at the heart of strategies, enacted both by the shantytown inhabitants and by the civil servants who deliver or claim them
Selection of suitable concentrated solar power farm’s locations A Case study: Fez-Meknes Region, Morocco
No full textNowadays, the transition to green energies becomes a necessity in the worldwide. In order to have an optimal yield, the selection of the adequate site for a given technology is required. In this study, the geographical environment of Fez-Meknes region, Morocco, is explored to select suitable location for concentrated solar power plants (CSP). For this purpose, a combination of a geographic information system (GIS) and the multi-criterion decision-making (MCDM) method is used for this aim. Various factors are taken into consideration, namely climate conditions, environment, water resources and location. These criteria are calculated and weighted using the Analytical Hierarchy Process (AHP) approach. The findings indicate that the Fez-Meknes region is a viable location for the implementation of CSP plants. Thus, the most suitable site represents 12% of the total region area. These suitable areas are located in the southern and southeastern part of the region with an irradiation value of about 6.57 kWh/m2/yr
L\u27univers emblématique du mythe dans Nedjma de Kateb-Yacine
No full textThe Emblematic Universe of the Myth in Nedjma by Kateb-Yacine
In this impenetrable symbolic maquis that is the novel Nedjma,the mythical word taken in the demonic cadence of a rebellious writing that is sometimes disconcerting breaks down the fiction creating an unusual world; produced plural representation thus enhancing the cryptogram-poetry. Poetry in movement destined to deliver the mythical word to greed; Changed fantasies of the author. Ardent symbolism and mystical breath will animate the episode of Nedjma
L’Andalousie dans l’œuvre poétique de Sergio Macías Brevis : mobilités et interactions culturelles
No full textRésumé
À travers El manuscrito de los sueños (Le manuscrit des rêves), l’auteur chilien Sergio Macías Brevis reflète une sensibilité poétique où s’imprime une écriture biographique qui est liée à une expérience vécue par le calife poète arabo-andalou Al Mouatamid Ibn Abbad. L’originalité de cette œuvre réside dans la revivification de la mémoire de ce calife très passionné de la poésie et du goût littéraire raffiné des auteurs de l’époque de l’épanouissement de la civilisation musulmane en Espagne. Il est important de préciser que ce recueil qui reprend les Lumières du Moyen-Âge arabo-andalou s’apparente à la dynamique de la reconstruction du monde poétiquement. À travers cette poésie productive, Brevis cherche à s’installer au cœur de l’époque andalouse en vue d’aboutir à son libre épanouissement et à une conscience profonde de son être-au-monde via le franchissement des limites de l’altérité et la mobilité de la mémoire. C’est ainsi que nous analyserons avec profondeur le dialogue interculturel entre ces espaces géographiques de l’Andalousie chargés d’histoire et de mémoire.
Mots-clés : Mobilités, Savoir, Diversité, Interactions, Transfert ;
Abstract
Through El manuscrito de los sueños (The manuscript of dreams), the Chilean author Sergio Macías Brevis reflects a poetic sensibility where a biographical writing is imprinted that intimates with an experience lived by the Arabo-Andalusian poet caliph Al Mouatamid Ibn Abbad. The originality of this work lies in the revivification of the memory of this caliph very passionate about poetry and refined literary taste of the authors of the time. It is revealing to specify that this collection which takes up the Enlightenment of the Arabo-Andalusian Middle Ages, is similar to the dynamics of the reconstruction of the world poetically. Through this productive poetry, Brevis seeks to settle in the heart of the Andalusian era in order to achieve his free blossoming and a deep awareness of his being-in-the-world through the crossing of the limits of the otherness of the other and the mobility of memory. This is how he worked to deepen the intercultural dialogue between these geographical spaces full of history and exchanges.
Keywords: Mobility, Knowledge, Diversity, Interactions, Transfer
Global Analysis for an HIV Infection Model with CTL Immune Response and Infected Cells in Eclipse Phase
No full textabstract: A modified mathematical model describing the human immunodeficiency virus (HIV) pathogenesis with cytotoxic T-lymphocytes (CTL) and infected cells in eclipse phase is presented and studied in this paper. The model under consideration also includes a saturated rate describing viral infection. First, the positivity and boundedness of solutions for nonnegative initial data are proved. Next, the global stability of the disease free steady state and the endemic steady states are established depending on the basic reproduction number R[subscript 0] and the CTL immune response reproduction number R[subscript CTL]. Moreover, numerical simulations are performed in order to show the numerical stability for each steady state and to support our theoretical findings. Our model based findings suggest that system immunity represented by CTL may control viral replication and reduce the infection.The final version of this article, as published in Applied Sciences, can be viewed online at: http://www.mdpi.com/2076-3417/7/8/86
Contribución de las imágenes Landsat 8 OLI al mapeo de lineamientos y series litológicas: implicaciones para la exploración de mineralizaciones de Pb-Zn en el macizo de Boudahar, Alto Atlas oriental, Marruecos
No full textThe Boudahar massif is located in the southern part of the eastern belt of the Moroccan High Atlas and it corresponds to a reef mass of about ten kilometers in length. Jbel Boudahar is a district of lead-zinc-barite mineralization, known by a strong artisanal exploitation of its ores. This district is characterized by its topography with a contrast of altitude and an arid environment, which makes the information acquired more valuable.
The processing of Landsat 8 OLI data allowed us to extract a lithological and structural map, aiming to make correlations to understand the distribution of lead-zinc mineralization. To this end, several tests were carried out, including the composition of color, principal component analysis and band ratio transformation.
The location of the main deposits at Jbel Boudhar coincides well with the lineament derived from band 1 of principal component analysis and with the dolomitic pliensbachian formations mapped by MNF and BR from Landsat Oli8. A remote sensing geological prospecting model has been established for the Jbel Boudhar lead-zinc deposits, providing a basis for future prospecting of new deposits in a similar context.El macizo de Boudahar se encuentra en la parte sur del cinturón oriental del Alto Atlas marroquí y corresponde a una masa arrecifal de unos diez kilómetros de longitud. Jbel Boudahar es un distrito de mineralización de plomo-zinc-barita, conocido por una fuerte explotación artesanal de sus minerales. Este distrito se caracteriza por su topografía con contrastes de altitud y ambiente árido, lo que hace más valiosa la información obtenida.
El procesamiento de datos Landsat 8 OLI nos permitió extraer un mapa litológico y estructural, con el objetivo de realizar correlaciones para entender la distribución de la mineralización de plomo-zinc. Para ello se realizaron varias pruebas, entre ellas la composición de color, análisis de componentes principales y transformaciones de ratios de bandas
La ubicación de los depósitos principales en Jbel Boudhar coincide bien con el lineamiento derivado de la banda 1 del análisis de componentes principales y con las formaciones dolomíticas pliensbachienses mapeadas por MNF y BR de Landsat OLI8. Así, se ha establecido un modelo de prospección geológica de detección remota para los depósitos de plomo y zinc de Jbel Boudhar, que proporciona una base para la prospección futura de nuevos depósitos en un contexto similar.
The processing of Landsat 8 OLI data allowed us to extract lithological and structural data in the Boudahar region, and to make correlations to understand the repartition of lead-zinc mineralization. Several tests were performed, including Color Composite, main component analysis, and band rationing transformation.
These results assign high precision to the mapping process using remote sensing, and provide a clear relationship regarding lineaments and lithology, which control the repartition of Boudahar massif mineralization’s
Identification, Characterization, and Deposit Model of Calcite Mineralization in the Middle Atlas Belts, Morocco
No full textThe Middle Atlas hosts calcite veins of considerable economic value, being found in the Mahdi and Bou Naceur ridges in the eastern part of the Moroccan Middle Atlas. In this study, we aim to identify the fundamental factors controlling mineralization, which could be essential for the exploration of calcite minerals. Jurassic dolomites and limestones host calcite deposits. Mineralization is controlled by the NE-SW sinistral fault system of the Mahdi Ridge as well as by the NW-SE dextral fault system of the Bou Naceur Ridge. These veins exhibit a Riedel shear system. The edges of the veins display different textures, such as banded and brecciated calcite. At the heart of the veins are deposits of massive, automorphic, pure crystalline calcite. Geochemical analyses revealed carbonate rock dissolution and carbonate fluid infiltration, indicating the presence of a low-temperature hydrothermal system. These mineralizations are a response to the evolution of the geodynamic uplift of the Middle Atlas during the Neogene, which occurred during the Alpine orogeny
Integrated remote sensing and field data for lithological mapping and calcite exploration in the Middle Atlas, Morocco
No full textThis study focuses on the application of remote sensing techniques for litho-structural mapping and calcite index detection in the Middle Atlas of Morocco. The aim is to generate a detailed geological map to understand the distribution of calcite veins and their relationship with geological structures. We utilized Aster and Landsat-8 OLI imagery, spatially enhanced with SPOT 5 data, for lithological mapping. Calcite indices were calculated using [(B6*B9)/(B8*B8)] to identify potential areas of calcite mineralization. Lineaments were extracted from a digital elevation model and Landsat-8 OLI principal component analysis (PCA) to delineate structural features. Results show a successful discrimination of lithological units and a predominant NE-SW orientation of lineaments in the Mehdi and Serghina Ridges. This system is aligned with branches of the South Middle Atlas fault. The spatial correlation between calcite indices and lineaments suggests a strong litho-structural control on calcite mineralization in the study area. This study demonstrates the effectiveness of remote sensing in mineral exploration and provides valuable insights into the geological context of calcite occurrences in the Middle Atlas
