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High-Order Schemes Combining the Modified Equation Approach and Discontinuous Galerkin Approximations for the Wave Equation

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Communications in Computational Physics 2012年第2期11卷 691-708页

作者： Cyril Agut Julien Diaz abdelaaziz ezziani LMA CNRS UMR 5142Universite de PauFrance INRIA Bordeaux Research Center Project Team Magique3DFrance

We present a new high ordermethod in space and time for solving the wave equation,based on a newinterpretation of the“Modified Equation”***,contrary to most of the works,we consider the time discretization before the space *** the time discretization,an additional biharmonic operator appears,which can not be discretized by classical finite *** propose a new Discontinuous Galerkinmethod for the discretization of this operator,andwe provide numerical experiments proving that the new method is more accurate than the classicalModified Equation technique with a lower computational burden.

关键词： High order schemes discontinuous Galerkin method acoustic wave equation

A Machine Learning Based Framework for a Stage-Wise Classification of Date Palm White Scale Disease

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Big Data Mining and Analytics 2023年第3期6卷 263-272页

作者： abdelaaziz Hessane Ahmed El Youssefi Yousef Farhaoui Badraddine Aghoutane Fatima Amounas STI Laboratory IDMSFaculty of Sciences and TechniquesMoulay Ismail University of MeknesErrachidia 52000Morocco. IA Laboratory Department of Computer ScienceFaculty of SciencesMoulay Ismail University of MeknesMeknes 50070Morocco. RO.AL&I Group Computer Sciences DepartmentFaculty of Sciences and TechniquesMoulay Ismail University of MeknesErrachidia 52000Morocco.

Date palm production is critical to oasis agriculture,owing to its economic importance and nutritional *** diseases endanger this precious tree,putting a strain on the economy and *** scale Parlatoria blanchardi is a damaging bug that degrades the quality of *** an infestation reaches a specific degree,it might result in the tree’s *** counter this threat,precise detection of infected leaves and its infestation degree is important to decide if chemical treatment is *** decision is crucial for farmers who wish to minimize yield losses while preserving production *** this purpose,we propose a feature extraction and machine learning(ML)technique based framework for classifying the stages of infestation by white scale disease(WSD)in date palm trees by investigating their leaflets images.80 gray level co-occurrence matrix(GLCM)texture features and 9 hue,saturation,and value(HSV)color moments features are extracted from both grayscale and color images of the used *** classify the WSD into its four classes(healthy,low infestation degree,medium infestation degree,and high infestation degree),two types of ML algorithms were tested;classical machine learning methods,namely,support vector machine(SVM)and k-nearest neighbors(KNN),and ensemble learning methods such as random forest(RF)and light gradient boosting machine(LightGBM).The ML models were trained and evaluated using two datasets:the first is composed of the extracted GLCM features only,and the second combines GLCM and HSV *** results indicate that SVM classifier outperformed on combined GLCM and HSV features with an accuracy of 98.29%.The proposed framework could be beneficial to the oasis agricultural community in terms of early detection of date palm white scale disease(DPWSD)and assisting in the adoption of preventive measures to protect both date palm trees and crop yield.

关键词： machine learning feature extraction ensemble learning diseases precision agriculture date palm

Spatiotemporal Distribution of Phlebotomine Sand Flies （Diptera： Psychodidae） in a Focus of Cutaneous Leishmaniasis in Foum Jamaa （Azilal, Atlas of Morocco）

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Journal of Life Sciences 2012年第10期6卷 1124-1132页

作者： Hassan Arroub abdelaaziz Alaoui Hicham El Miri Meryem Lemrani Khalid Habbari Laboratory of Management and Valorization of Naturals Resources FST Sultan Moulay Slimane University Beni Mellal 23000Morocco Faculte des Sciences Agdal Universite Mohamed V Agdal Rabat 10000 Morocco Laboratory of Leishmaniasis lnstitut Pasteur du Maroc Casablanca 20000 Morocco

An entomological survey of Phlebotomine sand flies （Diptera： Psychodidae） was carried out in three sectors of Foum Jamgta region （province of Azilal, Morocco） during the year 2010. Morphological identification was performed on a total of 1,152 sand flies （23% females and 77% males） collected by sticky paper traps. 80% of the total collected flies were identified as Phlebotomus （Paraphlebotomus） sergenti （Parrot）（57%） and Phlebotomus （Larroussius） longicuspis （Nitzulescu）（23%）. In addition to these dominant species, four other species were found, Phlebotomus （Phlebotomus） papatasi （Scopoli）, Sergentomyia （Sergentomyia） minuta （Rondani）, Phlebotomus （Larroussius） perniciosus （Newstead） and Phlebotomus （Paraphlebotomus） chabaudi （Croset）. Overall, the population dynamics show a yearly bimodal pattern related to rainfall and temperature, and with high density around human dwellings. The spatiotemporal distribution of sand fly species was helpful to discuss strategies that might be useful in controlling cutaneous leishmaniasis transmission in this endemic focus.

关键词： Phlebotomine sand flies cutaneous leishmaniasis temporal and spatial distribution Foum Jamaa Morocco.

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制造业就业、国际贸易与中国

中国经济报告 2020年第4期 40-55页

作者：阿卜杜拉阿齐兹·艾特·阿里尤里·达杜什新南方政策中心

本文旨在更好地理解全球制造业就业的演变。自2000年以来,制造业增加值增长迅速,这主要是因为对制成品的需求不断增长,尤其是发展中国家。不过,无论是在金融危机之前还是之后,制造业就业都增长得非常缓慢。制造业新增工作岗位只能为10%... 详细信息

本文旨在更好地理解全球制造业就业的演变。自2000年以来,制造业增加值增长迅速,这主要是因为对制成品的需求不断增长,尤其是发展中国家。不过,无论是在金融危机之前还是之后,制造业就业都增长得非常缓慢。制造业新增工作岗位只能为10%的新增劳动力和农村转移劳动力提供就业机会。大部分制造业新增工作岗位主要都在中国,大多数国家的制造业就业占比都在下降,还有一些国家(包括几乎所有发达国家)的制造业就业人口出现了绝对下降现象。中国的经济转型非常成功,使其就业人数大幅增长,但中国生产的大部分制成品都在国内消费了,尤其是金融危机之后更是如此,因此中国日益融入世界贸易并不是世界其他地区制造业就业停止增长的根本原因。在我们所研究的样本国家中,就业下降的主要原因是自动化和生产方法的改进使劳动生产率提高,而不是制造业贸易的变化,这与人们普遍的观点不一样。我们发现证明制造业(用不同方式衡量)的规模与经济快速发展之间有相关性的证据不多。

关键词：制造业就业国际贸易中国