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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： yusr. o el-dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis el-dib's frequency formula

Enhanced Chimp optimization Algorithm Using Attack Defense Strategy and Golden Update Mechanism for Robust CoVID-19 Medical Image Segmentation

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Journal of Bionic Engineering 2024年第4期21卷 2086-2109页

作者： Amir Hamza Morad Grimes Abdelkrim Boukabou Samira dib Non Testing Destructive Laboratory Faculty of TechnologyUniversity of Jijel18000JijelAlgeria Laboratory of Renewable Energy Faculty of TechnologyUniversity of Jijel18000JijelAlgeria

Medical image segmentation is a powerful and evolving technology in medical *** fact,it has been identified as a very effective tool to support and accompany doctors in their fight against the spread of the coronavirus(CoVID-19).Various techniques have been utilized for CoVID-19 image segmentation,including Multilevel Thresholding(MLT)-based meta-heuristics,which are considered crucial in addressing this ***,despite their importance,meta-heuristics have significant ***,the imbalance between exploration and exploitation,as well as premature convergence,can cause the optimization process to become stuck in local optima,resulting in unsatisfactory segmentation *** this paper,an enhanced War Strategy Chimp optimization Algorithm(WSChoA)is proposed to address MLT *** strategies are incorporated into the traditional Chimp optimization *** update mechanism that provides diversity in the ***,the attack and defense strategies are incorporated to improve the search space leading to avoiding local *** experimental results were conducted by comparing WSChoA with recent and well-known algorithms using various evaluation metrics such as Feature Similarity Index(FSIM),Structural Similarity Index(SSIM),Peak signal-to-Noise Ratio(PSNR),Standard deviation(STD),Freidman Test(FT),and Wilcoxon Sign Rank Test(WSRT).The results obtained by WSChoA surpassed those of other optimization techniques in terms of robustness and accuracy,indicating that it is a powerful tool for image segmentation.

关键词： Image processing Segmentation optimization Chimp Golden update mechanism Attack-defense strategy CoVID-19

Effectiveness of biofertilizers foliar application on yield and quality traits of flax(Linum usitatissimum L.)

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oil Crop Science 2024年第2期9卷 91-101页

作者： Saied el Sayed A.B.Bakry o.A.Nofal M.A.Abo Horish Plant Nutrition Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt Field Crops Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt

Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and *** have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein *** factors collectively contribute to the growth and development of ***,this study aims to investigate how three biofertilizers(Algae extract,CMS as a by-product of yeast,and Metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil *** field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in *** application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons *** applications of algae extract at a rate of 1.50 mL/L along with CMS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,Mn),seed oil content,and protein content in flax seeds during both *** highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/*** can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents.

关键词： Flax Bio fertilizers Seeds yield Nutrient contents Quality

Comparison between seismic analysis of twisting and regular 52-story towers considering soil-structure interaction

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 663-675页

作者： Mohamed Naguib Abouelsaad Mohammed Shaaban Salah el Bagalaty Mohamed E.el Madawy Structural Engineering Department Faculty of EngineeringMansura UniversityMansoura 35511Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 35712Egypt

A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise *** addition,the difference between the seismic performance of using twisting towers over regular ones is *** twisting tower is a simulation of the Evolution Tower(Moscow).The towers’skeletons consist of RC elements and rest on a reinforced concrete piled-raft *** soil model is considered as multi-layered with the same soil properties as the zone chosen for the analysis(New Mansoura City,Egypt).The only difference between both towers is their shape in *** whole system is modelled and analyzed in a single step as one full 3D model,which is known as the direct approach in *** analyses are carried out using finite-element software(Midas GTS NX).Dynamic output responses due to three records of seismic loads are proposed and presented in some *** on the results,it is concluded that SSI has a considerable effect on the dynamic response of tall buildings mainly because of the foundation flexibility,as it leads to lengthening the vibration period,increasing the story drift and the base shear for both cases.

关键词： soil-structure interaction seismic analysis twisting towers base shear story drift finite element method Midas GTS NX

Gender-Based Analysis of User Reactions to Facebook Posts

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Big Data Mining and Analytics 2024年第1期7卷 75-86页

作者： Yassine el Moudene Jaafar Idrais Rida el Abassi Abderrahim Sabour Mathematical Engineering and Computer Science Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco Department of Computer Science Mathematical−High School of Technology Ibn Zohr UniversityAgadir 8706Morocco

online Social Networks(oSNs)are based on the sharing of different types of information and on various interactions(comments,reactions,and sharing).one of these important actions is the emotional reaction to the *** diversity of reaction types available on Facebook(namely FB)enables users to express their feelings,and its traceability creates and enriches the users’emotional identity in the virtual *** paper is based on the analysis of 119875012 FB reactions(Like,Love,Haha,Wow,Sad,Angry,Thankful,and Pride)made at multiple levels(publications,comments,and sub-comments)to study and classify the users’emotional behavior,visualize the distribution of different types of reactions,and analyze the gender impact on emotion *** of these can be achieved by addressing these research questions:who reacts the most?Which emotion is the most expressed?

关键词： profiling knowledge extraction data mining emotion mining social media data crawling Facebook reactions gender

Existence results and behavior analysis for nonlinear age-dependent population dynamics problems with conformable fractional operator

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International Journal of Biomathematics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui M'hamed el omari Ali el Mfadel Khalid Hilal Laboratory of Applied Mathematics Scientific Computing Sultan Moulay Slimane University BP 523 Beni MellalMorocco

In this paper,we investigate the existence of solutions and analyze the large-time behavior for Gurtin-Maccamy population model involving conformable fractional *** a preliminary step,we construct a generic structure of the solution associated with our proposed model by utilizing some basic properties and tools of conformable fractional *** establish the existence of a unique solution of the given model with the given initial *** last,by using the upper and lower solutions for the characteristic equation,we define the upper and lower boundaries for the obtained solution and describe the large-time behavior of the total population.

关键词： Age-dependent population conformable fractional operator upper and lower boundary of the solution dynamics of populations

Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLoo S.el-BoRGI School of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) dispersion phase velocity

Modeling environmental sensitivity and risk assessment of PAHs in sediments along two marine coastal areas in Egypt

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Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.el-Alfy National Institute of oceanography and Fisheries NIOFCairoEgypt

Modeling the environmental sensitivity index(ESI)is vital in the planning and management processes,especially along the coastal *** main objectives of the study were to define the main sources of polycyclic aromatic hydrocarbons(PAHs),establish an ESI model,and measure the risk of PAHs on humans and the environment using various *** methodology of the research involved analyzing PAHs according to the EPA 550 methodology in sediments of the coastline in two important coastline areas in Egypt,namely the Gulf of Suez and the Mediterranean Sea,modeling the sensitivity of PAHs using ArcGIS 10.5 by integrating different physical,biological,and land use/cover factors,identifying the sources,and performing a risk *** sediment samples were collected from each *** produced sensitivity map could explain the highly sensitive areas along the Mediterranean Sea and Gulf of Suez coastlines(especially areas that were near drains'outlets,industrial sites,and sea ports).The highest mean PAH concentrations were Acenaphthylene and Fluorine in the Mediterranean Sea and Suez Gulf,***'s obvious that the individual PAH concentrations were within the ERL,ERM,and Pel threshold limits,indicating no adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,and Ant/Ant+Phe gave an indication that most PAH sources were petrogenic(63.64%)and others(36.36%)were from petroleum *** principle component analysis(PCA)indicated a diverse correlation among the isomer ratios and LU/LC *** carcinogenic risk values were in the very low category(or both children and *** most significant contributors to carcinogenicity were IP and BkFlu in the Mediterranean Sea and Suez Gulf,*** sources of carbon in seawater,especially with climatic change,may impact the aquatic environment and have impacts on organisms and coral *** it is highly recommended to keep shorelines and seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbons(PAHs) Modeling Sensitivity Gulf of Suez And Mediterranean sea

Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang Said el-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

Large magnetocaloric effect and magnetic properties of EuRho3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： M.Lassri M.Sajieddine A.elouafi A.el Hachmi S.el ouahbi R.Moubah Laboratory of Energy and Materials Engineering (LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial Management (EMINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of Mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on Matter and Instrumentation (LRMI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced Materials and Thermic (LPMAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSM),was determined by em ploying the thermodynam ic Maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSMand RCP show that the EuRho3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： X-ray photoelectron spectroscopy Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths