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Relative(n,k)-Weak Cotorsion Modules

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Algebra Colloquium 2024年第3期31卷 481-498页

作者： Mostafa Amini houda Amzil Driss Bennis Department of Mathematics Faculty of SciencesPayame Noor UniversityTehranIran Department of Mathematics Faculty of Sciences EI Jadida Chouaib Doukkali UniversityMorocco Department of Mathematics Faculty of Sciences Mohammed V University in RabatMorocco

Let R be a ring and n,k be two non-negative *** an extension of several known notions,we introduce and study(n,k)-weak cotorsion modules using the class of right R-modules with n-weak fat dimensions at most *** exampl... 详细信息

关键词： (n,k)-weak cotorsion module n-weak injective module n-weak fat module n-super finitely presented module

Analyses on an electronic voltage transformer's failure by its resonance with very fast transient overvoltage and suppression

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High Voltage 2024年第1期9卷 150-162页

作者： Ruoyu Han houda Zhu Qing Chen Hongbin Li Yue Tong Linshan Han Yang Jiao School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhanChina China Electric Power Research Institute WuhanChina School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhanChina

As voltage measuring devices are widely used in the high voltage power system with a primary-secondary-fusion structure,electronic voltage transformers are directly connected to the primary conductor and would face much more serious electromagnetic environments than general secondary *** a result,they would still experience failures even when general protection measures are adopted to suppress overvoltages'*** address this issue,an innovative method is proposed after analyses are conducted on the resonance between a transformer and an *** this method,an air-cored coil is installed in a transformer to artificially shift its natural frequency and to dodge the high-frequency dominant component of a transient overvoltage,avoiding the aforementioned resonance and suppressing the secondary *** addition,simulations and laboratory tests are conducted to prove this method's validity.

关键词： transient resonance mentioned

Chemically Mediated Interactions between Grapevine, Aphid, Ladybird, and Ant in the Context of Insect Chemical Ecology

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1523-1542页

作者： Taghreed Alsufyani Noura J.Alotaibi Nour houda M’sakni Mona A.Almalki Eman M.Alghamdi Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry Department Faculty of ScienceKing AbdulAziz UniversityP.O.Box 80200Jeddah21589Saudi Arabia

This study simpliﬁes the complex relationship among grapevine plants,aphids,ladybirds,and ants,which is essential for effective pest management and ecological *** study investigated the impact of aphid attacks and the presence of ants and ladybirds on the volatile compounds proﬁle released into the chemosphere of the community consisting of the common vine Vitis vinifera,the aphid Aphis illinoisensis,the ladybird Cocci-nella undecimpunctata-and the ant Tapinoma *** study aims to analyze the volatile compounds emitted by the grapevine and surrounding insects in response to these intricate *** extraction of volatile organic compounds(VOCs)was carried out using closed-loop stripping(CLS)and then analyzed via gas chromatography-mass spectrometry(GC-MS)and principles coordinated analysis(PCA)was *** grapevine was exposed to different types and order of treatments,including non-infested,aphid-infested,aphid-infested with ant,aphid-infested with ladybird,and various combinations of ant and *** the aphid attack,the outcomes uncovered massive alterations in the volatile compound proﬁ*** grapevine displayed distinct emissions of germacrene D,an alcohol,and an alkene compared to non-infested *** characteristic VOC proﬁle was the share of infested grapes in the presence of ants,with benzene derivatives and sesquiterpenes dominating the *** coexistence of ladybirds with ants and aphids resulted in a dif-ferent volatile proﬁle characterized by elevated levels of aldehydes,ketones,α-farnesene,and its hydroxy *** was concluded that the emission of VOCs into the chemosphere of the grapevine communities varied qualitatively and quantitatively depending on the level of the relationship complexity within each community in response to the infestation of grapevines by aphids,the presence of ladybirds as natural predators,and the presence of ant as *** grapevine’s status-dependent compounds

关键词： Aphids Aphis illinoisensis volatile organic compounds chemosphere pest management gas chromatography-mass spectrometry closed-loop stripping

Juvenile Systemic Sclerosis: About 9 Cases

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Open Journal of Pediatrics 2024年第2期14卷 320-326页

作者： Kaoutar Danaoui houda Nassih Khadija Oujennane Rabiy El Qadiry Aicha Bourrahouat Said Amal Imane Ait Sab B Pediatric Ward Mohammed VI University Hospital Center Marrakesh Morocco Dermatology Ward Mohammed VI University Hospital Center Marrakesh Morocco

Scleroderma is a rare disease with two primary forms: localized scleroderma (LS) and systemic sclerosis (SSc). Both are chronic conditions that can manifest in various patterns (subtypes) and are linked to extracutaneous involvement in pediatric patients. Juvenile SSc poses a higher risk of morbidity and mortality, with patients facing life-threatening complications such as lung, heart, and visceral organ fibrosis, and vasculopathy. In contrast, mortality is extremely rare in juvenile LS, but patients are susceptible to significant morbidity, leading to severe disfigurement and functional impairment. Treatment for scleroderma aims to control inflammation and address specific issues. An early diagnosis significantly enhances the overall outcome. This study conducts a retrospective descriptive analysis aiming to document the clinical manifestations, management approaches, and outcomes of systemic sclerosis in a cohort of nine children receiving treatment for juvenile systemic sclerosis at Pediatric B department of Mohammed VI University, Hospital Center in Marrakech, Morocco.

关键词： Scleroderma Systemic Sclerosis Children Pediatric

Adaptive high-order sliding mode control based on quasi-time delay estimation for uncertain robot manipulator

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Control Theory and Technology 2020年第3期18卷 279-292页

作者： Brahim brahmi Mark DRISCOLL Mohamed Hamza LARAKl Abdelkrim brahmi Department of Mechanical Engineering Musculoskeletal Biomechanics Research Lab McGill UniversityMontrealCanada Department of Electrical Engineering University of QuebecMontrealCanada

This paper presents the design,and validation of a new adaptive control system based on quasi-time delay estimation(Q-TDE)augmented with new integral second-order terminal sliding mode control(ISOTSMC)for a manipulator robot with unknown dynamicuncertainty and *** to the conventional[TDE,the proposed Q-TDE becomes sufficient to invoke a fixed artficial time delay and utilize the past data only of the control input to approximate the unknown system's dynamic *** incorporating of new adaptive reachinglaw with ISOTSMCaugmented with Q-TDE policy ensures the continuous performance tracking of the robot manipulator's trajectories using output *** combination may achieve high performance with a significant chattering reducing *** utilizing the Lyapunov function theory,it can be demonstrated that the robot system is stable and all signals in closed-loop are converging in finite ***,Simulation and comparative studies with two degrees of freedom robot manipulator were carried out to validate the effectiveness of the designed control scheme.

关键词： Second-order sliding mode quasi-time delay estimation(Q-TDE) adaptive reaching law

Positron Affinity, Deformation Potential and Diffusion Constant in AlxIn1-xSb Ternary Semiconductor Alloys

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Acta Metallurgica Sinica(English Letters) 2016年第7期29卷 661-667页

作者： Nour EI-houda Fares Nadir Bouarissa Materials and Electronic Systems Laboratory University of Bordj-Bou-Arr6ridj 34000 Bordj-Bou-Arr6ridj Algeria Laboratory of Materials Physics and Its Applications University of M'sila 28000 M'sila Algeria 9 Rue K Fg des martyrs 34000 Bordj-Bou-Arreridj Algeria

The present investigation deals with the positron behaviour in Alxlnl_xSb ternary semiconductor alloys in the zinc-blende phase. The calculations are mainly based on a pseudopotential approach coupled with the independent particle model. Features such as elastic constants, electron and positron chemical potentials, positron deformation potential and positron diffusion constant are determined. Moreover, the positron affinity to InSb, A1Sb and their related ternary alloys and heterostructures is calculated. The present results are compared to experiment and found to be in reasonably good agreement. The information gathered from the present study can help in understanding the positron trapping at interfaces and precipitates and might be useful in slow-positron-beam experiments.

关键词： Semiconductor alloys Positrons Diffusion Surface and interface states Heterostructures

Achieving an optimal shock-wave mitigation inside open channels with cavities for weak shock waves:A computational study

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Theoretical & Applied Mechanics Letters 2020年第5期10卷 354-365页

作者： N.brahmi A.Hadjadj Normandie University Institut National des Sciences Appliquées of RouenCNRSCORIA76000 RouenFrance

This paper deals with a numerical study of weak shock-waves propagation and their attenuation in channel flow having different heights and exhibiting a hollow circular cavities with different depths and diffraction angles *** effect of initial diffraction angle and cavity depth on the shock mitigation is investigated.A better shock attenuation is achieved with diffraction angle by a factor of approximately 17%in terms of shock-Mach number and 38%in terms of total *** obtained results show also,in addition to the initial diffraction angle and cavity depth,the importance of reducing the channel heights as well as the position of the reduced section in achieving an optimal shock-wave *** presence of a cavity inside the channel helps to attenuate faster the shock *** underlying physics relies on the shock diffraction phenomenon that generates large amount of vortical structures capable of dissipating part of the shock energy by inducing a pressure loss behind it.A subtle arrangement of channel position/height and a cavity location leads to an efficient pressure attenuation by approximately a factor of 57%forMs=1.6 and 16%for Ms=1.1..

关键词： Shock diffraction Shock reflection Shock attenuation Vortex generation

Modeling of secondary treated wastewater disinfection by UV irradiation: Effects of suspended solids content

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Journal of Environmental Sciences 2010年第8期22卷 1218-1224页

作者： Mounaouer brahmi Noureddine Hamed Belhadi Helmi Hamdi Abdennaceur Hassen Water Research and Technology Center Borj Cdria Science & Technology Park

This work aimed to study UV-resistant strains of Pseudomonas aeruginosa, to propose a formulation of the kinetics of secondary treated wastewater disinfection and to underline the influence of suspended solids on the inactivation kinetics of these strains. Some investigations were carried out for the validation of some simulation models, from the simplest, the kinetics model of Chick-Watson reduced to first order, to rather complex models such as multi-kinetic and Collins-Selleck models. Results revealed that the involved processes of UV irradiation were too complex to be approached by a simplified formulation, even in the case of specific strains of microorganisms and the use of nearly constant UV radiation intensity. In fact, the application of Chick-Watson model in its original form is not representative of the kinetics of UV disinfection. Modification, taking into account the speed change during the disinfection process, has not significantly improved results. On the other hand, the application of Collins-Selleck model demonstrates that it was necessary to exceed a least dose of critical radiation to start the process of inactivation. To better explain the process of inactivation, we have assumed that the action of disinfectant on the survival of lonely microorganisms is faster than its action on suspended solids protected or agglomerated to each others. We can assume in this case the existence of two inactivation kinetics during the processes （parallel and independent） of the first-order. For this reason, the application of a new kinetic model by introducing a third factor reflecting the influence of suspended solids in water on disinfection kinetics appeared to be determinant for modeling UV inactivation of P. aeruginosa in secondary treated wastewater.

关键词： secondary wastewater disinfection modeling UV irradiation kinetic suspended solids

Analysis of the Influence of Viscosity and Thermal Conductivity on Heat Transfer by Al2O3-Water Nanofluid

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Fluid Dynamics & Materials Processing 2020年第2期16卷 181-198页

作者： houda Jalali Hassan Abbassi Unit of Computational Fluid Dynamics and Transfer Phenomena National Engineering School of Sfax(ENIS)University of SfaxSfaxTunisia

The addition of nanoparticles into liquid,even at low concentrations,leads to an increase in both,dynamic viscosity and thermal ***,the increase in temperature causes an increase in thermal conductivity and a decrease in the nanofluid *** this context,a numerical investigation of the competition between viscosity and thermal conductivity about their effects on heat transfer by Al_(2)O_(3)-water nanofluid was conducted.A numerical study of heat transfer in a square cavity,filled with Al_(2)O_(3)-water nanofluid and heated from the left side,was presented in this ***,momentum,and thermal energy equations are solved by the finite volume *** the pressure-velocity coupling,the SIMPLER algorithm was *** working conditions,allowing the increase of heat transfer,are *** addition,two correlations for viscosity and thermal conductivity of Al_(2)O_(3)-water nanofluid as functions of the concentration and diameter size based on experimental measurement are *** correlations were more precisely compared to those given by the theoretical ***,other models for viscosity and conductivity depending on temperature are used and *** results reveal that heat transfer by Al_(2)O_(3)-water nanofluid is enhanced only when the temperature exceeds 40℃ and the diameter size does not exceed a certain limit of the order of 45-50 nm depending on temperature.

关键词： Heat transfer nanofluid viscosity thermal conductivity