检索结果-南通市图书馆

Open Journal of Geology 2021年第3期11卷 61-80页

作者： Mohammed El Attmani Amine Bouwafoud Salem Elouariti Hicham Si Mhamdi abdelmajid ben bouziane Mustapha Mouflih Sedimentary Basins Dynamic and Geological Correlations Laboratory Department of Geology Faculty of Science Ben M’sik Hassan II University of Casablanca Casablanca Morocco Laboratory of Applied Geology Department of Geosciences Faculty of Sciences and Techniques Errachidia Moulay Isma&#239 l University of Meknes Meknes Morocco

Globally, the Paleogene period experienced several events marking the Paleocene-Eocene transition which is especially to one of the hottest periods that the Earth has ever known (Paleocene-Eocene Thermal Maximum, PETM), followed by the biological crisis that affected benthic foraminifera. The Bekrit Syncline, subject of this study, shows three Formations of range from the Cretaceous to the Eocene ages (the El Koubbat, Irbzer and Bekrit-Timahdite Formations). Sedimentological, palynological and geochemical analyses of collected samples, in the Bekrit syncline, were studied to determine the paleogeographic and paleoenvironmental conditions of the Middle Atlas. The carbonate rocks were analyzed by microscopic study and geochemical analysis by X-ray Fluorescence (XF) and Inductively Coupled Plasma Spectrometry (ICP). The results obtained highlight the sedimentary events that took place during the Paleogene. Thus, the Maastrichtian is characterized by a closed euxinic marine environment shared by a more open and oxidizing environment. On the other hand, the Paleocene was a restricted marine environment with evaporitic sedimentation, while the Eocene sees the installation of a carbonate platform with a bioclastic Shoal.

关键词： Geochemistry Sedimentology Palynology Carbonates Phosphate Paleoenvironments Middle-Atlas

The Eocene Bryozoans of Bekrit-Timahdite Formation, Middle-Atlas, Morocco: Taxonomy, Paleoenvironments and Paleoclimates Implications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geoscience and Environment Protection 2021年第3期9卷 136-153页

作者： Mohammed El Attmani Amine Bouwafoud Salem Elouariti Hicham Si Mhamdi abdelmajid ben bouziane Mustapha Mouflih Sedimentary Basins Dynamic and Geological Correlations Laboratory Department of Geology Faculty of Science Ben M’sik Hassan II University Casablanca Morocco Laboratory of Applied Geology Department of Geosciences Faculty of Sciences and Techniques Errachidia Moulay Isma&iuml l University Meknes Morocco

Located in the North-West of the African continent, the Moroccan Middle Atlas constitutes an intra-continental chain within the Atlas domain. It is known by several global geological events such as the Paleocene-Eocene crisis during the Paleogene, which corresponds to one of the hottest periods on earth with Paleocene-Eocene thermal maximum (PETM). A taxonomic study carried out on the carbonate deposits of the Bekrit-Timahdite Formation from three sections of the Bekrit syncline allowed the identification of 5 species of the Cheilostome and Cyclostome Bryozoans (Cellaria rigida, Cellaria sinuosa, Aimulosia lamellosa, Heteropora and Osthimosia) in bioclastic limestones, nodular limestones, marly and sandy limestones. The interest of Bryozoans as indicators of paleoenvironments and paleoclimates was assessed by examining current communities, in terms of depth evolution as richness and abundance, distribution of taxonomic categories zoarium types, and zooidal morphology. The depositional environment analysis of Bryozoans showed a shallow marine carbonate platform with low sedimentation energy where is registered a relatively warm paleoclimate.

关键词： Bryozoans Eocene Taxonomy Carbonate Paleoenvironment Middle-Atlas

Late Cretaceous-Paleogene Formation of the Bekrit Syncline, Middle Atlas, Morocco: Sedimentology, Geochemistry, Palynology and Paleoenvironments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A New Method for Sentiment Analysis Using Contextual Auto-Encoders

Open Journal of Geology（地质学期刊） 2021年第3期

作者： Mohammed El Attmani Amine Bouwafoud Salem Elouariti Hicham Si Mhamdi abdelmajid ben bouziane Mustapha Mouflih

来源：评论

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2018年第6期33卷 1307-1319页

作者： Hanen Ameur Salma Jamoussi abdelmajid ben Hamadou Multimedia Information Systems and Advanced Computing Laboratory Sfax University Sfax Technopole Sfa 3021 Tunisia

Sentiment analysis, a hot research topic, presents new challenges for understanding users＇ opinions and judg-ments expressed online. They aim to classify the subjective texts by assigning them a polarity label. In this paper, weintroduce a novel machine learning framework using auto-encoders network to predict the sentiment polarity label at theword level and the sentence level. Inspired by the dimensionality reduction and the feature extraction capabilities of theauto-encoders, we propose a new model for distributed word vector representation ＂PMI-SA＂ using as input pointwise-mutual-information ＂PMI＂ word vectors. The resulted continuous word vectors are combined to represent a sentence. Anunsupervised sentence embedding method, called Contextual Recursive Auto-Encoders ＂CoRAE＂, is also developed forlearning sentence representation. Indeed, CoRAE follows the basic idea of the recursive auto-encoders to deeply composethe vectors of words constituting the sentence, but without relying on any syntactic parse tree. The CoRAE model consistsin combining recursively each word with its context words （neighbors＇ words： previous and next） by considering the wordorder. A support vector machine classifier with fine-tuning technique is also used to show that our deep compositionalrepresentation model CoRAE improves significantly the accuracy of sentiment analysis task. Experimental results demon-strate that CoRAE remarkably outperforms several competitive baseline methods on two databases, namely, Sanders twittercorpus and Facebook comments corpus. The CoRAE model achieves an efficiency of 83.28% with the Facebook dataset and97.57% with the Sanders dataset.

关键词： sentiment analysis recursive auto-encoder stacked auto-encoder pointwise mutual information deep embed-ding representation

Assessment of the power deposition on the MEGAPIE spallation target using the GEANT4 toolkit

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2019年第4期30卷 8-14页

作者： Abdesslam Lamrabet abdelmajid Maghnouj Jaouad Tajmouati Mohamed bencheikh Faculty of Sciences Dhar El Mahraz Laboratory of Integration of Systems and Advanced TechnologiesUniversity Sidi Mohamed Ben Abdellah El Hajeb

This work aims at evaluating the reliability of the GEANT4(GEometry ANd Tracking 4) Monte Carlo(MC) toolkit in calculating the power deposition on the Megawatt Pilot Experiment(MEGAPIE), the first liquid–metal spallation target worldwide. A new choice of codes to study and optimize this target is provided. The evaluation of the GEANT4 toolkit is carried out in comparison with the MCNPX and FLUKA MC codes. The MEGAPIE is an international project led by the Paul Scherrer Institute in Switzerland. It aims to demonstrate the safe operation of an intense neutron source to power the next generation of nuclear reactors, accelerator-driven systems(ADSs). In this study, we used the GEANT4 MC toolkit to calculate the power deposited by fast protons on the MEGAPIE *** calculation focuses on several structures and *** predictions of our calculations were compared and discussed with that of the MCNPX and FLUKA codes,adopted by the MEGAPIE project. The comparison shows that there is a very good agreement between our results and those of the reference codes.

关键词： GEANT4 Simulation MEGAPIE target Spallation Power deposition

Production threshold impact on a GEANT4 calculation of the power deposition in a fast domain: MEGAPIE spallation target

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2019年第5期30卷 40-47页

作者： Abdesslam Lamrabet abdelmajid Maghnouj Jaouad Tajmouati Mohamed bencheikh Laboratory of Integration of Systems and Advanced Technologies Faculty of Sciences Dhar El mahrazUniversity Sidi Mohamed Ben Abdellah El Hajeb

The calculation time in the Monte Carlo simulations consistently represents an essential issue. It is often very long, and its decrease constitutes a challenge for the simulator. Generally, an MC simulation is qualified as quality or not according to two main criteria: the calculation time and the accuracy of the results. However, in most cases, the optimization of one criterion affects negatively the other. Therefore, a compromise between both of them is always required in this kind of simulation. The present work aims at studying the impact of the production threshold(or cut) of the GEANT4 toolkit on the calculation of the power deposition in the MEGAPIE spallation *** production threshold of secondaries is a GEANT4 intrinsic parameter. It indicates the limit of energy we can reach in the production of secondary particles. This study has allowed us to make the following conclusions. First,the influence of the cut on the calculation of the deposited power depends on the volume size, its arrangement and the importance of the electromagnetic processes occurring within. Second, the accuracy of the calculations can be acceptable only below a given value of the cut ***, this accuracy remains almost unchangeable from a certain value of the cut. The study has also made it possible to explore the prevalence of certain interactions in the zone of spallation in the MEGAPIE target.

关键词： Production threshold Power deposition Spallation MEGAPIE GEANT4

Fluid Flow and Convective Heat Transfer in a Water Chemical Condenser

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2020年第2期16卷 199-209页

作者： Mounir Kriraa Khalid Souhar Driss Achemlal Youssef Ait Yassine abdelmajid Farchi IMII Ingénierie Management et Innovation IndustriellFSTHassan 1er UniversitySettatMorocco LMPEQ National School of Applied SciencesSafiCadi Ayyad UniversityMarrakechMorocco LGEMS Laboratory National School of Applied SciencesIbn Zohr UniversityAgadir80000Morocco Engineering Sciences Laboratory Department of MathematicsPhysics and InformaticsPolydisciplinary Faculty of TazaSidi Mohamed Ben Abdellah UniversityFezMorocco Ibn Zohr University Higher School of TechnologyLaâyouneMorocco Ibn Zohr University Faculty of ScienceLaboratory of Thermodynamics and EnergyAgadirMorocco

In this paper,a detailed investigation of water(Pr=7.0)convection in a chemical condenser is carried *** openings are located along one side of the *** Navier-Stokes equations are solved in the frame of a control volume method using the SIMPLEC algorithm to implement adequate coupling of pressure and *** emphasis is given to the influence of the Reynolds number,the tilt of the channel and the Rayleigh number on the convective heat *** are presented and discussed allowing the control parameters to span relatively wide intervals:Rayleigh number(10^(4)≤Ra≤5×10^(5)),channel inclination(0°≤90°)and Reynolds number(10≤Re≤1000).On the basis of these results,a new correlation of the Nusselt number is elaborated.

关键词： Chemical condenser tilted channel convection numerical study heat transfer

Lithological Mapping Using Landsat 8 OLI in the Meso-Cenozoic Tarfaya Laayoune Basin (South of Morocco): Comparison between ANN and SID Classification

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Geology 2021年第12期11卷 658-681页

作者： Amine Bouwafoud Mustapha Mouflih abdelmajid benbouziane Hassan II University of Casablanca Faculty of Sciences Ben M’sik Geosciences and Application Laboratory (LGA) Sidi Othmane Casablanca Morocco

In the Saharian domain, the Tarfaya-Laayoune coastal basin developed in a stable passive margin, where asymmetrical sedimentation increase from East to West and reach a sediment stack of about 14 kilometers. However, the morphology of the studied area corresponds to a vast plateau (hamada) presenting occasional major reliefs. For this purpose, remote sensing approach has been applied to find the best approaches for truthful lithological mapping. The two supervised classification methods by machine learning (Artificial Neural Network and Spectral Information Divergence) have been evaluated for a most accurate classification to be used for our lithofacies mapping. The latest geological maps and RGB images were used for pseudo-color groups to identify important areas and collect the ROIs that will serve as facilities samples for the classifications. The results obtained showed a clear distinction between the various formation units, and very close results to the field reality in the ANN classification of the studied area. Thus, the ANN method is more accurate with an overall accuracy of 92.56% and a Kappa coefficient is 0.9143.

关键词： Tarfaya-Laayoune Basin Geological Mapping Supervised Classification Artificial Neural Network Spectral Information Divergence