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When Finitely Generated δ-Supplemented Modules Are Supplemented

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Algebra Colloquium 2015年第1期22卷 119-130页

作者： rachid Tribak Centre Pedagogique Regional (CPR) - Tanger Avenue My A bdelaziz Souani BP: 3117 Tangier 90000 Morocco

We investigate the structure of rings over which every finitely generated g- supplemented module is supplemented. Some characterizations of this type of rings are given. We establishe some properties of ⊙-δ-supplemented modules. It is showed that for a ring R, finitely generated δ-supplemented R-modules are supplemented if and only if finitely generated ⊙-δ-supplemented R-modules are ⊙-supplemented.

关键词： right △-ring (δ-)small submodule (δ-)supplemented module ⊙-(δ-)supple-mented module (δ-)local module

Use of a calibrated SWAT model to evaluate the effects of agricultural BMPs on sediments of the Kalaya river basin (North of Morocco)

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International Soil and Water Conservation Research 2019年第2期7卷 176-183页

作者： Harnza Briak rachid Mrabet rachid Moussadek Khadija Aboumaria Department of Earth Sciences Faculty of Sciences and Techniques(FST)Abdelmalek Essaadi UniversityPostal Box 41690000 TangierMorocco Department of Environment and Natural Resources Scientific DivisionNational Institute for Agricultural Research(INRA)Postal Box 41510000 RabatMorocco

Soil erosion from agricultural fields is a worldwide problem,to influence water quality,soil fertility and reservoir sedimentation especially in Mediterranean countries such as *** fact,this work assesses the effects of Best Management Practices (BMPs) on sediments using the Soil and Water Assessment Tool (SWAT) model in the Kalaya watershed in Northem Morocco,to recommend the most appropriate *** study is based on the use of three most usable practices:contouring,stripcropping and terracing,by the calibrated SWAT *** general parameters of the model have been modified to reflect the implementation of different agricultural BMPs *** sediment yield were compared with the baseline scenario,for ***,the effective measures to reduce sediment losses at the watershed level are organized according to their effectiveness,and these are terracing (28% reduction and the value is 15t/ha/yr) followed by strip-cropping (9% reduction and the value is 5t/ha/yr).In contrast,measurements performed by the contouring are inappropriate for the study area because they have contributed to increasing the soil erosion (more than 31% of losses and the value is 17t/ha/yr more than existing conditions).Therefore,the model illustrates that the terrace is effective for reducing sediment losses and limiting soil erosion especially on steep ***,the results provide useful information for targeted management in order to implement the most effective agricultural BMPs in the watershed.

关键词： Modeling Agricultural BMPs Sediment SWAT Kalaya river basin North Morocco

On Modules Satisfying the Descending Chain Condition on Cyclic Submodules

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Algebra Colloquium 2020年第3期27卷 531-544页

作者： Farid Kourki rachid Tribak Centre Regional des Metiers de l'Education et de la Formation(CRMEF)-Tanger Annexe de Larache B.P.4063LaracheMorocco Centre Regional des Metiers de l'Education et de la Formation(CRMEF-TTH)-Tanger Avenue My Abdelaziz SouaniB.P.3117TangierMorocco

A module satisfying the descending chain condition on cyclic submodules is called *** class of coperfect modules lies properly bet ween the class of locally artinian modules and the class of semiartinian *** R be a commutative ring with *** show that every semiartinian Ti-module is coperfect if and only if R is a *** is also shown that the class of coperfect R-modules coincides with the class of locally artinian R-modules if and only if m/m^(2)is a finitely genera ted R-module for every maximal ideal m of R.

关键词： coperfect modules locally artinian modules perfect rings semiartinian modules(rings)

Quark-novae in neutron star - white dwarf binaries: a model for luminous (spin-down powered) sub-Chandrasekhar-mass Type Ia supernovae?

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Research in Astronomy and Astrophysics 2013年第4期13卷 435-464页

作者： rachid Ouyed Jan Staff Department of Physics and Astronomy University of Calgary2500 University Drive NW Department of Physics and Astronomy Louisiana State University

We show that, by appealing to a Quark-Nova （QN） in a tight binary system containing a massive neutron star and a CO white dwarf （WD）, a Type Ia explosion could occur. The QN ejecta collides with the WD, driving a shock that triggers carbon burning under degenerate conditions （the QN-Ia）. The conditions in the compressed low-mass WD （MwD 〈 0.9 M） in our model mimic those of a Chandrasekhar mass WD. The spin-down luminosity from the QN compact remnant （the quark star） pro- vides additional power that makes the QN-Ia light-curve brighter and broader than a standard SN-Ia with similar 56Ni yield. In QNe-Ia, photometry and spectroscopy are not necessarily linked since the kinetic energy of the ejecta has a contribution from spin-down power and nuclear decay. Although QNe-Ia may not obey the Phillips relationship, their brightness and their relatively ＂normal looking＂ light-curves mean they could be included in the cosmological sample. Light-curve fitters would be con- fused by the discrepancy between spectroscopy at peak and photometry and would correct for it by effectively brightening or dimming the QNe-Ia apparent magnitudes, thus over- or under-estimating the true magnitude of these spin-down powered SNe-Ia. Contamination of QNe-Ia in samples of SNe-Ia used for cosmological analyses could systematically bias measurements of cosmological parameters if QNe-Ia are numerous enough at high-redshift. The strong mixing induced by spin-down wind combined with the low 56Ni yields in QNe-Ia means that these would lack a secondary maximum in the/-band despite their luminous nature. We discuss possible QNe-Ia progenitors.

关键词： stars evolution - stars binary - stars neutron - stars white dwarfs - supernovae general

Thermodynamics Properties of Confined Particles on Noncommutative Plane

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Communications in Theoretical Physics 2019年第9期71卷 1047-1053页

作者： rachid Houca Ahmed Jellal Equipe de Physique Theorique et Hautes Energies Faculte des SciencesUniversite Ibn ZohrP.O.Box8106AgadirMaroc Saudi Center for Theoretical Physics DhahranSaudi Arabia Laboratory of Theoretical Physics Faculty of SciencesChouaib Doukkali UniversityP.O.Box 2024000El JadidaMorocco

We consider a system of N particles living on the noncommutative plane in the presence of a confining potential and study its thermodynamics properties. Indeed, after calculating the partition function, we determine the corresponding internal energy and heat capacity where different corrections are obtained. In analogy with the magnetic field case, we define an effective magnetization and study its susceptibility in terms of the noncommutative parameter θ.By introducing the chemical potential, we investigate the Bose-Einstein condensation for the present system. Different limiting cases related to the temperature and θ will be analyzed as well as some numerical illustration will be presented.

关键词： confining potential noncommutative plane thermodynamics properties Bose-Einstein condensation

Comparison of climatic threshold of geographical distribution between dominant plants and surface pollen in China

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Science China Earth Sciences 2008年第8期51卷 1107-1120页

作者： CHEDDADI rachid BEAUDOUIN Celia Institut des Sciences de l'Evolution Universite Montpellier II Montpellier 34095France Department of Earth Sciences Sun Yat-sen UniversityGuangzhou 510275China

The geographical distribution of dominant plant species in China was georeferenced and climatic variables were interpolated into all ***,the percentage distributions of principal pollen taxa based on 1860 surface pollen sites in China were selected and the related climate values were interpolated with the same method. The geographical and climatic comparison between the two data-sets indicated that the climate threshold of most pollen taxa from surface pollen is coherent with plant distributions. The climatic envelopes of dominant plant are mostly accordant with those of pollen taxa at certain levels. However, some distinct offsets of the climate ranges exist between the two datasets for most pollen taxa identified at family level, such as Ericaceae,Asteraceae, Poaceae and Chenopodiaceae. The present study provides for the first time rich information on temperature and precipitation in relation to pollen and plant distribution based on the datasets on a continental scale useful for global ecological modeling and Quaternary palaeoclimate reconstruction.

关键词： surface pollen dominant plant species geographical distribution climate global changes

A decision loop for situation risk assessment under uncertainty: A case study of a gas facility

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Petroleum 2021年第3期7卷 343-348页

作者： Antar Simohammed rachid Smail LRPI Laboratory Algeria Institute of Health and Safety University of Batna 2Algeria

This paper presents a decision-making support system for situation risk assessment associated with critical alarms conditions in a gas *** system provides a human operator with advice on the confirmation and classification of occurred *** input of the system comprises uncertain and incomplete *** the light of uncertain and incomplete information,different uncertainties laws have been associated with the probabilistic assessment of the system loops which combine data of several sources to reach the ultimate *** implemented model used Observe-OrientDecide-Act loop(OODA)combined with Bayesian *** show that the system can classify the alarms system.

关键词： OODA loop Bayesian networks Decision making Situation risk assessment Uncertainty Information Alarms system Emergency

Selecting and optimal sizing of hybridized energy storage systems for tidal energy integration into power grid

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 113-122页

作者： Seifeddine BEN ELGHALI rachid OUTBIB Mohamed BENBOUZID LIS-UMR CNRS 7020 University of Aix-Marseille UMR CNRS 6027 IRDL University of Brest Shanghai Maritime University

The high penetration of renewable energy systems with fluctuating power generation into the electric grids affects considerably the electric power quality and supply ***, energy storage resources are used to deal with the challenges imposed by power variability and demand-supply *** main focus of this paper is to investigate the appropriate storage technologies and the capacity needed for a successful tidal power ***, a simplified sizing method, integrating an energy management strategy, is *** method allows the selection of the adequate storage technologies and determines the required least-cost storage capacity by considering their technological limits associated with different power *** optimal solutions given by the multi-objective evolutionary algorithm are presented and analyzed.

关键词： Tidal energy Energy storage system Optimal sizing Selection

On Baer-Kaplansky Classes of Modules

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Algebra Colloquium 2017年第4期24卷 603-610页

作者： Derya Keskin Tutuncu rachid Tribak Department of Mathematics Hacettepe University 06800 Beytepe Ankara Turkey Centre Regional des Metiers de L'Education et de la Formation (CRMEF)-Tanger Avenue My Abdelaziz Souani B.P. 3117 Thngier Morocco

We are interested in studying when the class of local modules is Baer- Kaplansky. We provide an example showing that even over a commutative semisimple ring R, we can find two non-isomorphic simple R-modules S1 and S2 such that the rings EndR（S1） and EndR（S2） are isomorphic. We show that over any ring R, the class of semisimple R-modules is Baer Kaplansky if and only if so is the class of simple R-modules.

关键词： Baer Kaplansky class of modules local modules semisimple rings