28 research outputs found

    Design of F-16 Airfoil Mock-ups for Supersonic Wind Tunnel: Study, Production, Testing and Validation

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    This research paper presents a comprehensive investigation into the behavior of viscous supersonic laminar flow and the Shock Wave- Laminar Boundary Layer Interaction (SWBLI) around the F-16 laminar NACA 6-series airfoil NACA 64A204. The study aims to establish and compare different methods for accurately describing these complex phenomena, which are of significant importance in the development of advanced aerospace technologies. To achieve this objective, a unique approach was adopted, involving the design and production of a mock-up F-16 airfoil equipped with pressure taps for use in the supersonic burst wind tunnel AF300. The mock-up was then experimentally tested, and the obtained data were analysed using numerical simulations with Ansys Fluent and a theoretical model based on a previously established analytical SWBLI model. The results obtained from the experimental, numerical, and analytical analyses validate the designed NACA 64A204 mock-up to a great extent. The study provides valuable insights into the physics of viscous supersonic laminar flow and SWBLI, contributing to a better understanding of these phenomena. The findings of this study will have important applications in the design of high-speed aircraft and other advanced aerospace technologies.Comment: 14 pages, 17 figures, 5 tables, submitted to Jounral of Applied Fluid Mechanic

    Application of Geophysics for the Detection of Derangement of Phosphate Layers in the Oulad Abdoun Basin in Morocco

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    The phosphate series of the basin of Oulad Abdoun begins in Maastrichtian with phosphate deposits relatively very marly. It ends at the Lutetian by a calcareous slab. Derangement is any disruption of the usual succession of the phosphate series and that which disrupts the evolution of the kinematic chain, leading to a decrease in production and profitability. In this case, we have a partially disturbed series and the disturbance consists of all the elements of the series (limestone, flint, marls and phosphate). The present work has been carried out in two ways: The present work has been carried out in two ways: The first one, purely geological, consists of the identification of the different layers of the Ouled Abdoun basin in the El Halassa site and their continuity to the outcrop. At the end of these observations, the basin shows derangement of two kinds: a disturbance on the scale of the whole series known as major disturbance, and a second which affects only part of the series. Thus, it is a minor or local disturbance. The second one, geophysics, is the application of three geophysical methods: electric tomography, magnetism, and refraction seismic. The correlation of these applications should result in delineating the mineralized zone and tracking all elements that in one way or another affect this mineralization. These elements are referred to as "derangement". The combination of the results of these two methods (vertical electrical survey and tomography) used allowed us to identify and map the disturbed places in the chosen area of El Halassa. The study will be extended to other sites and the results can be compared and correlated to understand the extent and origin of these disturbances

    Geophysical Characterization of Disturbances in the Phosphate Series of the OuladAbdoun, Morocco: Relationship with Atlasictectonics

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    The sedimentary phosphates series from the Upper Maastricht to the Lutetion of the OuladAbdoun sedimentary basin is almost identical at the basin-scale. It is made up by alternation of either phosphate or non-phosphate sub-horizontal levels. The series was characterized by rhythmic sedimentation under the form of successive elementary sequences. On the other hand, the series of SidiChennaneis distinguished by the presence of local disturbances defined by the miners under the term "dérangements". These "dérangements", which are less frequent at other mining sites (MEA Lahrech, El Hlassa, Point A), are a notable problem during extraction and remain a real obstacle at phosphate mining sites. The morphology of these "dérangements" is almost subcircular to subconical sinkholes and chaotic bodies of anarchical materials. They are fontis type paleokarsts, it is an amalgam of highly altered yellowish brecciated rusty material whose lithological nature reflects that of the surrounding series. They also reflect endokarst siliceous and ferruginous neoformedfacies in the empty spaces of the palaeokarst. The origin of the palaeokarstshasbeen linked to the presence of NE-SW trend faults that have favoured the alteration and dissolution of the gypsum and chalk facies of the Senonian. The regular spatial distribution of these fontisis well related to the regionalAtlasictectonics. This study aims to investigate these problems in its geological aspect, in order to characterize and understand their origin. The purpose of this work isto compare the results obtained by electric tomography, gravimetry and lineament mapping and match them with geological data to draw a meaningful conclusion on the existence of these disturbances and their spatial distribution in relation to tectonic

    BALANCED SCORECARD : ENJEUX DE L’I NFORMATION ENTRE CONSTAT ET PRATIQUE DE LA PERFORMANCE

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    La performance des entreprises est au coeur des prĂ©occupations de plusieurs chercheurs et professionnels en gestion. Depuis plusieurs annĂ©es, ils Ă©tudient les diffĂ©rents liens entre des variables contextuelles comme la stratĂ©gie, la structure ou encore l’incertitude perçue de l’environnement et l’effet combinĂ© de ces facteurs sur la performance de l’entreprise. Il s’agit en fait, d’un systĂšme de mesure de la performance permettant aux responsables a tous les niveaux un autocontrĂŽle de leurs activitĂ©s par la dĂ©clination de la stratĂ©gie en termes opĂ©rationnels, mettre l’organisation en adĂ©quation avec la stratĂ©gie, transformer la stratĂ©gie en un processus continue,
 on parle du tableau de bord. Ce travail s’inscrit dans une dĂ©marche constructiviste de conception et de mise en Ɠuvre de Balanced Scorecard. En fait ce dernier est l’un des outils les plus utilisĂ©s pour l’évaluation des performances au sein des entreprises. Toutefois, sa conception, par les contrĂŽleurs de gestion, pose souvent des difficultĂ©s en termes de systĂšmes d’information adĂ©quats afin de mieux rĂ©pondre aux attentes et besoins de ses diffĂ©rents utilisateurs

    Development of Bioinformatics Infrastructure for Genomics Research in H3Africa

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    Background: Although pockets of bioinformatics excellence have developed in Africa, generally, large-scale genomic data analysis has been limited by the availability of expertise and infrastructure. H3ABioNet, a pan-African bioinformatics network, was established to build capacity specifically to enable H3Africa (Human Heredity and Health in Africa) researchers to analyze their data in Africa. Since the inception of the H3Africa initiative, H3ABioNet’s role has evolved in response to changing needs from the consortium and the African bioinformatics community. Objectives: H3ABioNet set out to develop core bioinformatics infrastructure and capacity for genomics research in various aspects of data collection, transfer, storage, and analysis. Methods and Results: Various resources have been developed to address genomic data management and analysis needs of H3Africa researchers and other scientific communities on the continent. NetMap was developed and used to build an accurate picture of network performance within Africa and between Africa and the rest of the world, and Globus Online has been rolled out to facilitate data transfer. A participant recruitment database was developed to monitor participant enrollment, and data is being harmonized through the use of ontologies and controlled vocabularies. The standardized metadata will be integrated to provide a search facility for H3Africa data and biospecimens. Because H3Africa projects are generating large-scale genomic data, facilities for analysis and interpretation are critical. H3ABioNet is implementing several data analysis platforms that provide a large range of bioinformatics tools or workflows, such as Galaxy, the Job Management System, and eBiokits. A set of reproducible, portable, and cloud-scalable pipelines to support the multiple H3Africa data types are also being developed and dockerized to enable execution on multiple computing infrastructures. In addition, new tools have been developed for analysis of the uniquely divergent African data and for downstream interpretation of prioritized variants. To provide support for these and other bioinformatics queries, an online bioinformatics helpdesk backed by broad consortium expertise has been established. Further support is provided by means of various modes of bioinformatics training. Conclusions: For the past 4 years, the development of infrastructure support and human capacity through H3ABioNet, have significantly contributed to the establishment of African scientific networks, data analysis facilities, and training programs. Here, we describe the infrastructure and how it has affected genomics and bioinformatics research in Africa

    Development of Bioinformatics Infrastructure for Genomics Research:

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    Although pockets of bioinformatics excellence have developed in Africa, generally, large-scale genomic data analysis has been limited by the availability of expertise and infrastructure. H3ABioNet, a pan-African bioinformatics network, was established to build capacity specifically to enable H3Africa (Human Heredity and Health in Africa) researchers to analyze their data in Africa. Since the inception of the H3Africa initiative, H3ABioNet's role has evolved in response to changing needs from the consortium and the African bioinformatics community

    African Genomic Medicine Portal: A Web Portal for Biomedical Applications

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    Genomics data are currently being produced at unprecedented rates, resulting in increased knowledge discovery and submission to public data repositories. Despite these advances, genomic information on African-ancestry populations remains significantly low compared with European- and Asian-ancestry populations. This information is typically segmented across several different biomedical data repositories, which often lack sufficient fine-grained structure and annotation to account for the diversity of African populations, leading to many challenges related to the retrieval, representation and findability of such information. To overcome these challenges, we developed the African Genomic Medicine Portal (AGMP), a database that contains metadata on genomic medicine studies conducted on African-ancestry populations. The metadata is curated from two public databases related to genomic medicine, PharmGKB and DisGeNET. The metadata retrieved from these source databases were limited to genomic variants that were associated with disease aetiology or treatment in the context of African-ancestry populations. Over 2000 variants relevant to populations of African ancestry were retrieved. Subsequently, domain experts curated and annotated additional information associated with the studies that reported the variants, including geographical origin, ethnolinguistic group, level of association significance and other relevant study information, such as study design and sample size, where available. The AGMP functions as a dedicated resource through which to access African-specific information on genomics as applied to health research, through querying variants, genes, diseases and drugs. The portal and its corresponding technical documentation, implementation code and content are publicly available

    African Genomic Medicine Portal: A Web Portal for Biomedical Applications

    Get PDF
    Genomics data are currently being produced at unprecedented rates, resulting in increased knowledge discovery and submission to public data repositories. Despite these advances, genomic information on African-ancestry populations remains significantly low compared with European- and Asian-ancestry populations. This information is typically segmented across several different biomedical data repositories, which often lack sufficient fine-grained structure and annotation to account for the diversity of African populations, leading to many challenges related to the retrieval, representation and findability of such information. To overcome these challenges, we developed the African Genomic Medicine Portal (AGMP), a database that contains metadata on genomic medicine studies conducted on African-ancestry populations. The metadata is curated from two public databases related to genomic medicine, PharmGKB and DisGeNET. The metadata retrieved from these source databases were limited to genomic variants that were associated with disease aetiology or treatment in the context of African-ancestry populations. Over 2000 variants relevant to populations of African ancestry were retrieved. Subsequently, domain experts curated and annotated additional information associated with the studies that reported the variants, including geographical origin, ethnolinguistic group, level of association significance and other relevant study information, such as study design and sample size, where available. The AGMP functions as a dedicated resource through which to access African-specific information on genomics as applied to health research, through querying variants, genes, diseases and drugs. The portal and its corresponding technical documentation, implementation code and content are publicly available

    Effect of Relative Velocity Between Rough Surfaces: Hydrodynamic Lubrication of Rotary Lip Seal

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    Since the sixties, most of numerical studies that model the rotary lip seal lubrication have been restricted by assuming that one of the two opposing surfaces is smooth: either the lip or the shaft. This hypothesis, although it is verified only for a shaft roughness ten times smaller than that of the seal, is the best solution to avoid the transient term “∂h/∂t” in the deterministic approach. Thus, the subject of the present study is twofold. The first part validates the current hydrodynamic model with the international literature by assuming the asperities on the lip and shaft as a two-dimensional cosine function. In the second part the Reynolds equation for rough surfaces with relative motion is solved. The numerical results show that the relative motion between rough surfaces impacts significantly the load support and the leakage rate, but affects slightly the friction torque
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