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stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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

作者： Yusry 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

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

Intravesical instillation of platelet-rich plasma for treatment of interstitial cystitis/bladder pain syndrome:A pilot study

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Current Urology 2024年第1期18卷 49-54页

作者： Ahmed s.el Hefnawy Mohamed Attya Ahmed Hasan Esam el sawy Mohamed Abdel-Razik Nasr el-Tabey Mansoura Urology and Nephrology Center Faculty of MedicineMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the feasibility of intravesical instillation of platelet-rich plasma(PRP)to treat interstitial cystitis/bladder pain syndrome(IC/BPs).Materials and methods:Twenty PRP samples were tested in vitro for stability after exposure to urine samples with different pH.A pilot study involving 21 female patients with IC/BPs was conducted,and 6 weekly doses of autologous PRP(50 mL)were *** were followed up at the 2nd,4th,8th,and 12th weeks after terminating *** primary endpoint was the visual analog scale(VAs)for pain,and the secondary endpoints included the IC symptom index,IC problem index of the O'Leary-sant questionnaire and global response assessment,urine culture,and *** was defined as a reduction in VAs by 30%or more compared with basal level,and adverse events were ***:The mean±sD of VAs was significantly reduced compared with basal level(4.4±2.6 vs.8.8±1.1,respectively,p=0.001).Meanwhile,80%of cases were considered successful,with a 50.1%reduction in the mean score compared with the basal *** mean±sD of IC symptom index and IC problem index significantly improved compared with the basal *** response assessment was markedly,moderately,and slightly improved in 2(10%),10(50%),and 5(25%)patients,respectively,and showed no change in 3(15%).Three patients had positive urine cultures at follow-up,but 1 withdrew after 2 sessions because of a lack of ***:Repeated intravesical instillation of PRP could be considered an effective and safe approach for treating IC/BPs.

关键词： Bladder pain syndrome Interstitial cystitis Platelet-rich plasma

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

A hybrid machine-learning model for solar irradiance forecasting

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Clean Energy 2024年第1期8卷 100-110页

作者： Ameera M.Almarzooqi Maher Maalouf Tarek H.M.el-Fouly Vasileios E.Katzourakis Mohamed s.el Moursi Constantinos V.Chrysikopoulos Department of Industrial and systems Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE electrical Engineering and Computer science Department Khalifa University Abu DhabiUAE Department of Civil Infrastructure and Environmental Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE school of Chemical and Environmental Engineering Technical University of CreteChaniaGreece

Nowcasting and forecasting solar irradiance are vital for the optimal prediction of grid-connected solar photovoltaic(PV)power *** plants face operational challenges and scheduling dispatch difficulties due to the fluctuating nature of their power *** the generation capacity within the electric grid increases,accurately predicting this output becomes increasingly essential,especially given the random and non-linear characteristics of solar irradiance under variable weather *** study presents a novel prediction method for solar irradiance,which is directly in correlation with PV power output,targeting both short-term and medium-term forecast *** proposed hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression *** proposed method excels in forecasting solar irradiance,especially during highly intermittent weather periods.A key strength of our model is the incorporation of multiple historical weather parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable *** evaluated the performance of our model using data sets from both cloudy and sunny days in seattle and Medford,UsA and compared it against three forecasting models:persistence,modified 24-hour persistence and least *** on three widely accepted statistical performance metrics(root mean squared error,mean absolute error and coefficient of determination),our hybrid model demonstrated superior predictive accuracy in varying weather conditions and forecast horizons.

关键词： solar power generation kernel ridge regression hybrid model forecasting

Evaluation of the nutritional value of Artemia nauplii for European seabass(Dicentrarchus labrax L.)larvae

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Aquaculture and Fisheries 2024年第1期9卷 78-84页

作者： Alaa A.el-Dahhar Rashwan s.Rashwan samy Y.el-Zaeem shaimaa A.shahin Mona M.Mourad Mohammed F.el Basuini Animal and Fish Production Department Faculty of Agriculture-Saba BashaAlexandria UniversityAlexandria21526Egypt National Institute of Oceanography and Fisheries(NIOF) Cairo11562Egypt Department of Animal Production Faculty of AgricultureTanta UniversityTanta31527Egypt Faculty of Desert Agriculture King Salman International UniversitySouth Sinai46618Egypt

Adapted European seabass(Dicentrarchus labrax L.)larvae at 25 days post-hatching(dph)with a primary weight and length of 23 mg and 9.92 mm,start the weaning up to 46 dph using the weaning micro-diet(54%crude protein from fish meal,powder milk,and poultry egg)concurrently with Artemia enriched with fortification emulsions(0.6 g/L)of DHA selco®as a control group(DHAs)or Fish oil+20%Vitamin C(FOVC),or Fish oil+20%Vitamin E(FOVE),or Fish oil+10%Vit.C+10%Vit.E(FOCE),or Fish oil only(FO).At 46 dph,groups of larvae fed enriched Artemia with DHAs and FOVE exhibited the highest final body weight,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the lowest feed conversion ***,larvae in FOVC displayed the lowest final body weight,total length,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the highest feed conversion *** histological assessment exhibited no pathological alteration as well as an improvement in the structure with DHAs,FOVE,FOVC,and FOCE co-additives compared to *** peroxidase enzyme(GPx)recorded the highest rates(Ps fed Artemia supplemented with DHAs and FOVE followed by FOCE and *** the lowest record for GPx activity was noted in the FO *** conclusion,Using augmented Artemia nauplii with fish oil+vitamin E in single or in companion with vitamin C as cheap antioxidants support *** larval growth,survival,and antioxidant efficacy during the critical weaning period.

关键词： European seabass Gastrointestinal histology Antioxidants Vitamin C Vitamin E DHA

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(st 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

Assessment of plant diversity of endemic species of the saharo-Arabian region in Egypt

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Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa s ABO HATAB Yassin M AL-sODANY Kamal H sHALTOUT soliman A HAROUN Mohamed M el-KHALAFY Botany and Microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

savanna, semi-deserts, and hot deserts characterize the saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, south sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of sinai Peninsula, 53 taxa). sahara regional subzone(ss1) distributes all the 126 endemic species, Arabian regional subzone(ss2) owns 79 taxa, and Nubo-sindian subzone(ss3) distributes only 14 endemics. seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINsPAN) to the saharo-Arabian endemic sp

关键词： endemism phytogeographical regions saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINsPAN)