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Human impact gradients via anthropogenic pollen indicators:insights gleaned from a case study in the Rif Mountains(Northern Morocco)

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Journal of Mountain Science 2024年第12期21卷 4223-4235页

作者： Aboubakr BOUTAHAR Paloma Cariñanos GONZALEZ Zouhaire LAMRANI abderrahmane merzouki Biology Ecologyand Health LaboratoryDepartment of BiologyFaculty of Sciences of TetouanAbdelmalek Essaâdi UniversityTetouan 93002Morocco Department of Botany Faculty of PharmacyUniversity of GranadaGranada 18071Spain Andalusian Institute for Earth System Research(IISTA-CEAMA) University of GranadaGranada 18100Spain Biology Environmentand Sustainable Development LaboratoryENSAbdelmalek Essaadi UniversityTetouan 93000Morocco CANN-MED&BALDIYA CROPS SARL Tangier 90010Morocco

Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environmental management *** numerous studies on fossil pollen records in the Rif landscape,research specifically focusing on modern pollen and its implications for understanding human impact on the natural landscape is notably *** paper presents novel anthropogenic pollen indicators for the Rif Mountains and seeks to evaluate the gradients of human impact on the southern Mediterranean *** employed a combination of modern pollen analysis,vegetation survey,and ordination techniques,incorporating various environmental and land-use *** correspondence analysis(CCA)allowed us to evaluate the relationships between pollen types and environmental variables,helping us identify key anthropogenic pollen indicators associated with land use and human activities:Poaceae,Cannabist,Olea-t,and Asteraceae for cultivation;Brassicaceae,Genista-t,Poaceae,Asteraceae and Plantago-t,for grazing;Apiaceae,Urtica-t and Genista-t for slashing and ***,an anthropogenic index score(AIS)was calculated for each sampled *** analysis(CA)was then used to correlate each specific pollen type with levels of human impact as follows(a)low(e.g.,Cedrus atlantica-t,Quercus canariensis-t),(b)moderate(e.g.,Erica-t,Arbutus unedo-t,Eucalyptus-t),and(c)high(e.g.,Cannabis-t,Brassicaceae,Olea-t,Nicotiana-t).This paper enhances our comprehension of land-use dynamics and impact levels,providing essential insights for evaluating anthropogenic impact trends and human-induced changes in the Rif Mountains landscape.

关键词： Modern Pollen analysis Rif mountains Pollen indicators Human impact Northern Morocco Anthropogenic index score

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Active Queue Management Exploiting the Rate Information in TCP-IP Networks

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 223-231页

作者： abderrahmane Boudi Malik Loudini Laboratoire de la Communication dans les Systemes Informatiques Ecole nationale Superieure d'Informatique ESI Algiers 16309 Algeria IEEE

In this paper, we propose a new mechanism called explicit rate notification(ERN) to be used in end-to-end communications. The ERN scheme encodes in the header of transmission control protocol(TCP) packets information about the sending rate and the round trip time(RTT) of the flows. This new available information to the intermediate nodes(routers) is used to improve fairness, increase utilization, decrease the number of drops, and minimize queueing delays. Thus, it induces a better management of the queue. A comparison of our scheme with preexistent schemes, like the explicit congestion notification scheme, shows the effectiveness of the proposed mechanism.

关键词： Active queue management congestion control fairness transmission control protocol(TCP)

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ISOGENOUS OF THE ELLIPTIC CURVES OVER THE RATIONALS

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Journal of Computational Mathematics 2002年第4期20卷 337-348页

作者： abderrahmane Nitaj Mathematik Universitat des SaarlandesPostfach 15 1150D-66041SaarbrockenGermany

An elliptic curve is a pair (E,O), where E is a smooth projective curve of genus 1 and O is a point of E, called the point at infinity. Every elliptic curve can be given by a Weierstrass equationE:y2+a1xy+a3y=x2+a2x2+a4x+*** Q be the set of rationals. E is said to be dinned over Q if the coefficients ai, i = 1, 2, 3, 4, 6 are rationals and O is defined over *** E/Q be an elliptic curve and let E(Q)tors be the torsion group of points of E defined over Q. The theorem of Mazur asserts that E(Q)tors is one of the following 15 groupsWe say that an elliptic curve E'/Q is isogenous to the elliptic curve E if there is an isogeny, i.e. a morphism φ: E → E' such that φ(O) = O, where O is the point at *** give an explicit model of all elliptic curves for which E'(Q)tors is in the form Z/mZ where m = 9, 10, 12 or Z/2Z × Z/2mZ where m = 4, according to Mazur's theorem. Morever, for every family of such elliptic curves, we give an explicit model of all their isogenous curves with cyclic kernels consisting of rational points.

关键词： Courbe elliptique Isogenie

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An incommensurate fractional discrete macroeconomic system:Bifurcation,chaos,and complexity

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Chinese Physics B 2023年第3期32卷 58-67页

作者： abderrahmane Abbes Adel Ouannas Nabil Shawagfeh Department of Mathematics University of JordanAmman 11942Jordan Department of Mathematics and Computer Science University of Larbi Ben M'hidiOum El Bouaghi 04000Algeria

This study proposes a novel fractional discrete-time macroeconomic system with incommensurate *** dynamical behavior of the proposed macroeconomic model is investigated analytically and *** particular,the zero equilibrium point stability is investigated to demonstrate that the discrete macroeconomic system exhibits chaotic *** using bifurcation diagrams,phase attractors,the maximum Lyapunov exponent and the 0–1 test,we verified that chaos exists in the new model with incommensurate fractional ***,a complexity analysis is carried out utilizing the approximation entropy(ApEn)and C_(0)complexity to prove that chaos ***,the main findings of this study are presented using numerical simulations.

关键词： chaos macroeconomic system discrete fractional calculus complexity

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Coupled Lamé System with a Viscoelastic Term and a Strong Discrete Time Delays

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Journal of Partial Differential Equations 2024年第2期37卷 121-134页

作者： BENIANI abderrahmane Engineering and Sustainable Development Laboratory Faculty of Science and TechnologyUniversity of Ain TemouchentAin Temouchent 46000Algeria

In this paper,we consider a coupled Lamé system with a viscoelastic damping in the first equation and two strong discrete time *** prove its existence by using the Faedo-Galerkin method and establish an exponential d... 详细信息

关键词： Lamésystem coupled system Lyapunov function delay term

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New design of ferroelectric solar cell combined with luminescent solar concentrator

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Chinese Physics B 2019年第8期28卷 417-424页

作者： Slimane Latreche Mohamed Fathi abderrahmane Kadri Unité de Développement des Equipements Solaires UDES/Centre de Développement des Energies RenouvelablesCDERTipaza 42415Algeria Laboratoire d'Etude des Matériaux Optoélectronique & Polymères Department of PhysicsUniversity of Oran 1 Ahmed Ben BellaBP 1524 El M'NaouerOran 31000Algeria

A new transparent photovoltaic panel composed of a luminescent solar concentrator and Al/BaTiO3/ZnO/Pt ferroelectric solar cells is presented,in which a portion of the incoming solar illumination is converted by the fluorophores to ultraviolet(UV)light which is then absorbed by ***,the solar cells are simulated using ***,the panel is modelled based on the obtained solar cell *** panel would be of great importance for building integrated photovoltaics domain because of its high transparency.

关键词： Atlas-Silvaco ferroelectric solar cell luminescent solar concentrator building integrated photovoltaic

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Comparative characterisation of conventional and textured 11􀯓kV insulators using the rotating wheel dip test

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High Voltage 2020年第6期5卷 739-746页

作者： Adnan Krzma Maurizio Albano abderrahmane Haddad Advanced High Voltage Engineering Research Centre School of EngineeringCardiff UniversityWalesUK Department of Electrical and Computer Engineering Faculty of EngineeringElmergib UniversityAl-KhomLibya

Surface tracking and erosion is an irreversible degradation occurring on the insulator surface, and this can ultimately lead to failure of the insulator. Polymeric materials such as silicone rubber have many advantages;including a superior hydrophobic surface. However, polymers are exposed to ageing and degradation resulting from electrical and environmental stresses. The rotating wheel dip test is adopted to conduct a comparative study of surface conduction on the two insulators. A conventional design has been selected and compared with insulators having textured surface. Monitoring of the shed surface and insulator trunk using an IR camera were carried out to assess the temperature distribution along insulator profiles. A spatial analysis was also performed to identify key features of the two designs. Localised surface conductance measurements are proposed in this study. This helps to understand and distinguish the trends of conductance and its distribution on each surface, helping to predict the future surface degradation associated to each design。

关键词： insulator rotating character

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Sequential extraction of Cs and Sr from Ain Oussera soils around Es-Salam research reactor facility

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Journal of Environmental Sciences 2015年第10期27卷 163-172页

作者： Abdelkader Bouzidi abderrahmane Ararem Djillali Imessaoudene Benalia Yabrir Centre de Recherche Nucléaire de Birine 17200 Ain OusseraAlgeria Laboratory of Exploration and Valorization of Steppic Ecosystems University of Djelfa

Four types of undisturbed soil in Ain Oussera region around the Es-Salam reactor facility,located in the south of Algiers, Algeria, at about 200 km, were artificially contaminated for one year with stable CsCl and SrCl2 in order to simulate an accidental release of these elements. This study was performed using sequential extraction procedure based on Shultz method and containing six fractions. The selectivity of the extraction protocol was confirmed by analyzing some elements（Ca, C, Fe, Mn, Si and Al） designed as indicators of the targeted phases. The obtained results showed an acceptable reproducibility, in view of the coefficients of variation that were in most cases less than 15%. The results revealed a clear proportional correlation between the extracted Cs and Sr in fractions for each soil and some of soils physicochemical properties. Organic matter appears to play an important role in the soil retention, particularly for Cs where the extracted percentage exceeds to 30% in whole soils. In contrast, strontium expresses a remarkable affinity for the fraction bound to carbonates. The obtained data also indicate that the availability of Cs in the four soils is less important compared to Sr availability. This is illustrated by the higher value of extracted Sr in the easily extractible phase, including the water-soluble and the exchangeable fraction.

关键词： Ain Oussera soils CsCl SrCl2 Sequential extraction Selectivity

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Recognition of Offline Handwritten Arabic Words Using a Few Structural Features

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Computers, Materials & Continua 2021年第3期66卷 2875-2889页

作者： abderrahmane Saidi Abdelmouneim Moulay Lakhdar Mohammed Beladgham Department of Electrical Engineering Laboratory:LTITTahri Mohammed UniversityBechar08000Algeria

Handwriting recognition is one of the most significant problems in pattern recognition,many studies have been proposed to improve this recognition of handwritten text for different ***,Fewer studies have been done for the Arabic language and the processing of its texts remains a particularly distinctive problem due to the variability of writing styles and the nature of Arabic scripts compared to other *** present paper suggests a feature extraction technique for offlineArabic handwriting recognition.A handwriting recognition system for Arabic words using a few important structural features and based on a Radial Basis Function(RBF)neural networks is *** methods of feature extraction are central to achieve high recognition *** proposed methodology relies on a feature extraction technique based on many structural characteristics extracted from the word skeleton(subwords,diacritics,loops,ascenders,and descenders).In order to reach our purpose,we built our own word database and the proposed system has been successfully tested on a handwriting database of Algerian city names(wilayas).Finally,a simple classifier based on the radial basis function neural network is presented to recognize certain words to verify the reliability of the proposed feature *** experiments on some images of the benchmark IFN/ENIT database show that the proposed system improves recognition and the results obtained are indicative of the efficiency of our technique.

关键词： Offline Arabic handwriting recognition preprocessing feature extraction structural features RBF neural network

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A GENERAL DECAY AND OPTIMAL DECAY RESULT IN A HEAT SYSTEM WITH A VISCOELASTIC TERM

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Acta Mathematica Scientia 2019年第2期39卷 618-626页

作者： abderrahmane YOUKANA Salim A.MESSAOUDI Aissa GUESMIA Department of Mathematics University of Batna Department of Mathematics and Statistics KFUPM Elie Cartan Institute of Lorraine Universite de Lorraine Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals

We consider a quasilinear heat system in the presence of an integral term and establish a general and optimal decay result from which improves and generalizes several stability results in the literature.

关键词： heat equation viscoelastic general decay optimal

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