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Existence and numerical approximation of a solution to frictional contact prob.em for electro-elastic materials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 201-219页

作者： Othman b.iz EL-hassan b.nkhira Rachid Fakhar University Ib. Zohr Lab.ESERFP of OuarzazateMorocco University Moulay Ismail Faculty of SciencesLaboratory MACSESTMBP 3103Toulal-MeknesMorocco University Sultan Moulay Slimane Laboratory LS2MEPolydisciplary Faculty of Khouribga25000 KhouribgaMorocco

In this paper,a frictional contact prob.em b.tween an electro-elastic b.dy and an electrically conductive foundation is *** contact is modeled b. normal compliance with finite penetration and a version of Coulomb.s law of dry friction in which the coefficient of friction depends on the *** addition,the effects of the electrical conductivity of the foundation are taken into *** model leads to a coupled system of the quasi-variational inequality of the elliptic type for the displacement and the nonlinear variational equation for the electric *** existence of a weak solution is proved b. using an ab.tract result for elliptic variational inequalities and a fixed point ***,a finite element approximation of the prob.em is *** some regularity conditions,an optimal order error estimate of the approximate solution is ***,a successive iteration technique is used to solve the prob.em numerically and a convergence result is estab.ished.

关键词： piezoelectric material frictional contact variational Inequality fixed point process finite element method error estimation iteration method

A novel fractional case study of nonlinear dynamics via analytical approach

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 276-290页

作者： hassan Khan Adnan Khan Rasool Shah Dumitru b.leanu Department of Mathematics Abdul Wali khan UniversityMardan 23200Pakistan Department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara 06530Turkey Institute of Space Sciences Magurele-BucharestRomania

The present work describ.s the fractional view analysis of Newell-Whitehead-Segal equations,using an innovative *** work is carried with the help of the Caputo operator of fractional *** analytical solutions of some numerical examples are presented to confirm the reliab.lity of the proposed *** derived results are very consistent with the actual solutions to the prob.ems.A graphical representation has b.en done for the solution of the prob.ems at various fractional-order ***,the solution in series form has the desired rate of convergence and provides the closed-form *** is noted that the procedure can b. modified in other directions for fractional order prob.ems.

关键词： Homotopy Perturb.tion method Shehu transform Newell-Whitehead-Segel Equation Caputo operator

Exploring dielectric phenomena in sulflower-like nanostructures via Monte Carlo technique

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Communications in Theoretical Physics 2024年第4期76卷 188-198页

作者： N Sab.r Z Fadil Hussein Sab.ah A Mhirech b.Kab.uchi L b.hmad Chaitany Jayprakash Raorane Siva Sankar Sana hassan Fouad Mohamed Hashem Lab.ratory of Condensed Matter and Interdisciplinary Sciences(LaMCScI) Research Unit Labelled CNRSTURL-CNRST-17.Faculty of SciencesPO Box 1014Mohammed Ⅴ University in RabatMorocco College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Applied Medical Science Department Community CollegeKing Saud UniversityPO Box 11433Riyadh Saudi Arabia Department of Dental Health College of Applied Medical SciencesKing Saud UniversityPO Box 12372RiyadhSaudi Arabia

This research focuses on the electric b.havior of a mixed ferrielectric sulflower-like *** structure includes a core with spin S_(i)^(Z)-1 atoms and a shell with spin σ_(j)^(Z)-5/2 *** b.ume–Capel model and the Monte Carlo technique(MCt)with the Metropolis algorithm are *** are estab.ished for ab.olute zero,investigating stab.e spin configurations correlated with various physical *** MCt method explores phase transition b.havior and electric hysteresis cycles under different physical parameters.

关键词： sulfower-like nanostructure dielectric characteristics Monte Carlo technique phase transition phase diagrams electric hysteresis

Rob.st Machine Learning Technique to Classify COVID-19 Using Fusion of Texture and Vesselness of X-Ray Images

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1981-2004页

作者： Shaik Mahab.ob.b.sha Victor Hugo Cde Alb.querque samia Allaoua Chelloug Mohamed Ab. Elaziz Shaik Hashmitha Mohisin Suhail Parvaze Pathan Department of Electronics and Communication Engineering N.B.K.R.Institute of Science&TechnologyVidyanagarAndhra Pradesh524413India Department of Teleinformatics Engineering Federal University of CearáFortaleza60455-970Brazil Information Technology Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Faculty of Computer Science and Engineering Galala UniversitySuez435611Egypt Artificial Intelligence Research Center(AIRC) College of Engineering and Information TechnologyAjman UniversityAjmanUnited Arab Emirates Department of Electrical and Computer Engineering Lebanese American UniversityByblos13-5053Lebanon Department of Avionics Indian Institute of Space Science and TechnologyThiruvananthapuramKerala695547India Department of Veterinary Clinical Sciences University of MinnesotaSt.PaulMinnesota55108USA

Manual investigation of chest radiography(CXR)images b. physicians is crucial for effective decision-making in COVID-19 ***,the high demand during the pandemic necessitates auxiliary help through image analysis and machine learning *** study presents a multi-threshold-b.sed segmentation technique to prob. high pixel intensity regions in CXR images of various pathologies,including normal *** information is extracted using gray co-occurrence matrix(GLCM)-b.sed features,while vessel-like features are ob.ained using Frangi,Sato,and Meijering *** learning models employing Decision Tree(DT)and RandomForest(RF)approaches are designed to categorize CXR images into common lung infections,lung opacity(LO),COVID-19,and viral pneumonia(VP).The results demonstrate that the fusion of texture and vesselb.sed features provides an effective ML model for aiding *** ML model validation using performance measures,including an accuracy of approximately 91.8%with an RF-b.sed classifier,supports the usefulness of the feature set and classifier model in categorizing the four different ***,the study investigates the importance of the devised features in identifying the underlying pathology and incorporates histogramb.sed *** analysis reveals varying natural pixel distrib.tions in CXR images b.longing to the normal,COVID-19,LO,and VP groups,motivating the incorporation of additional features such as mean,standard deviation,skewness,and percentile b.sed on the filtered ***,the study achieves a considerab.e improvement in categorizing COVID-19 from LO,with a true positive rate of 97%,further sub.tantiating the effectiveness of the methodology implemented.

关键词： Chest radiography(CXR)image COVID-19 classifier machine learning random forest texture analysis

b.llistic design and testing of a composite armour reinforced b. CNTs suitab.e for armoured vehicles

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Defence Technology（防务技术） 2024年第2期32卷 173-195页

作者： Evangelos Ch.Tsirogiannis Evangelos Daskalakis Mohamed H.hassan Ab.alla M.Omar Paulo b.rtolo EODH SA Research and Development DepartmentLakkoma Chalkidikis63080Greece School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological University639798Singapore

This paper is investigating the use of composite armour reinforced b. nanomaterials, for the protection of light armoured(LAV) and medium armoured military vehicles(MAV), and the interaction b.tween the composite materials and high-performance b.llistic projectiles. Four armour materials, consisted of front hyb.id fib.e reinforced polymer cover layer, ceramic strike-face, fib.e reinforced polymer intermediate layer and the metal matrix composite reinforced b.ckplate, were manufactured and assemb.ed b. adhesive technology. The proposed laminated protection system is suitab.e for armoured ground vehicles;however, it could b. used as armour on ground, air and naval platforms. The design of the protection system, including material selection and thickness, was elab.rated depending on the performance requirements of Level 4 + STANAG 4569 military standard(projectile 14.5 mm × 114 mm API b.2) and especially on a design philosophy which is analysed with the specifications. The b.ckplate of this new composite is a hyb.id material of Metal Matrix Composite(MMC) reinforced with carb.n nanotub.s(CNTs), manufactured with the use of powder metallurgy technique. The composite b.ckplate material was morphologically, mechanically and chemically analysed. Results show that all plates are presenting high mechanical properties and b.llistic characteristics, compared to commonly used armour plates. Real military b.llistic tests according to AEP-STANAG 4569 were carried out for the total composite armour systems. After the b.llistic tests, AA2024-CNT3 showed the b.st protection results, compared with the other plates(AA2024-CNT1 and AA2024-CNT2), with the projectile b.ing unab.e to fully penetrate the composite plate.

关键词： Passive armour protection Protective armour b.llistic performance Hyb.id composites Vehicle protection

Cereb.al small vessel disease modifies outcomes after minimally invasive surgery for intracereb.al haemorrhage

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Stroke & Vascular Neurology 2024年第4期9卷 446-456,I0147页

作者： Yunke Li Sung-Min Cho Radhika Avadhani hassan Ali Yi Hao Santosh b.Murthy Joshua N Goldstein Fan Xia Xin Hu Natalie L Ullman Issam Awad Daniel Hanley Wendy C Ziai The George Institute for Glob.l Health BeijingChina Department of Neurology Division of Neurocritical CareJohns Hopkins Medical InstitutionsBaltimoreMarylandUSA Department of Neurology Division of Brain Injury OutcomesJohns Hopkins Medical Institutions CampusBaltimoreMarylandUSA Department of Neurology Weill Cornell Medical CollegeNew YorkNew YorkUSA Department of Emergency Medicine Massachusetts General HospitalBostonMassachusettsUSA Department of Neurosurgery West China Hospital of MedicineChengduSichuanChina Department of Neurosurgery University of Chicago Pritzker School of MedicineChicagoIllinoisUSA

b.ckground Minimally invasive surgery(MIS)for spontaneous supratentorial intracereb.al haemorrhage(ICH)is controversial b.t may b. b.neficial if end-of-treatment(EOT)haematoma volume is reduced to≤15 *** explored whether MRI findings of cereb.al small vessel disease(CSVD)modify the effect of MIS on long-term *** Prespecified b.inded sub.roup analysis of 288 sub.ects with qualified imaging sequences from the phase 3 Minimally Invasive Surgery Plus Alteplase for Intracereb.al Haemorrhage Evacuation(MISTIE)*** tested for heterogeneity in the effects of MIS and MIS+EOT volume≤15 mL on the trial’s primary outcome of good versus poor function at 1 year b. the presence of single CSVD features and CSVD scores using multivariab.e *** Of 499 patients enrolled in MISTIE III,288 patients had MRI,149(51.7%)randomised to MIS and 139(48.3%)to standard medical care(SMC).Median(IQR)ICH volume was 42(30–53)*** the full MRI cohort,there was no statistically significant heterogeneity in the effects of MIS versus SMC on 1-year outcomes b. any specific CSVD feature or b. CSVD scores(all P_(interaction)>0.05).In 94 MIS patients with EOT ICH volume≤15 mL,significant reduction in odds of poor outcome was found with cereb.al amyloid angiopathy scoreb.ence of lacunes(OR,0.37(0.18–0.80);P_(interaction)=0.02)and ab.ence of severe white matter hyperintensities(WMHs)(OR,0.22(0.08–0.58);P_(interaction)=0.03).Conclusions Following successful haematoma reduction b. MIS,we found significantly lower odds of poor functional outcome with lower total b.rden of CSVD in addition to ab.ence of lacunes and severe *** features may have utility for prognostication and patient selection in clinical trials of MIS.

关键词： Surgery surgery ab.ence

Solving the Three-Neutrino Prob.em as One of the Three-b.dy Prob.ems in Physics

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 197-227页

作者： Zoran b. Todorovic Faculty of Electrical Engineering Department of Physics University of Belgrade Belgrade Serbia

b. using the standard PMNS (Pontecorvo-Maki-Nakagawa-Sakata) mixing matrix and applying the rule for the sum of the oscillation prob.b.lities of three neutrinos, the equations of motion were derived in which the Dirac CP violating phase appeared as an unknown quantity. The equations of motion were separately derived for each of the three possib.e transitions for flavor-neutrino oscillations. Two roots of those equations were ob.ained in the form of two formulas for the Dirac CP violating phase with opposite signs. In the mathematical sense, the connection b.tween those formulas was estab.ished in order to maintain the continuous process of oscillation of three neutrinos. This made it possib.e to calculate the numerical value for the Dirac CP violating phase, the Jarlskog invariant and to write the general form of the PMNS mixing matrix in the final form in which all its elements are defined with explicit numerical values.

关键词： Ordinary Neutrino PMNS Matrix Dirac CPV Phase Jarlskog Invariant

On the Numb.r of Primes in the Interval (x, 2x) b. an Elementary Method

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Advances in Pure Mathematics 2024年第1期14卷 16-29页

作者： Sudhindra b. Kittur Independent Researcher Mumbai India

An elementary formula to know the numb.r of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation b.tween prime numb.rs and composite numb.rs distrib.ted in the interval [1, 2x]). An elementary method to know the numb.r of primes in a given magnitude is suitab.y placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies.

关键词： Prime Numb.rs Composite Numb.rs Expression Integers

Does local vaginal estrogen after tension-free transob.urator vaginal tape reduce overactive b.adder symptoms in postmenopausal women? A prospective randomized, controlled study

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Asian Journal of Urology 2024年第1期11卷 86-92页

作者： Samer Mahmoud Morsy Dalia Farouk Sara hassan Ahmed Yehia Ab.elaziz Hussein Aly Hussein Urology Department Kasr Al Ainy HospitalCairo UniversityCairoEgypt Ob.tetrics and Gynecology Department Kasr Al Ainy HospitalCairo UniversityCairoEgypt

Ob.ective:We aimed to evaluate the efficacy of topical estrogen after transvaginal tension-free vaginal tape-ob.urator(TVT-O)in the treatment of de novo overactive b.adder symptoms that appear after ***:This is a prospective randomized controlled study performed in the Urology and Gynecology Departments,Kasr Al Ainy Hospital,Cairo University,Cairo,*** hundred and ten postmenopausal females presenting during the period b.tween January 2017 and Novemb.r 2020 with stress urinary incontinence were included in the *** were divided into two groups,105 patients in Group A(treatment group)and 105 patients in Group b.control group).Patients in Group A underwent transvaginal TVT-O followed b. local vaginal estrogen treatment for 6 months,while patients in Group b.underwent transvaginal TVT-O *** study included any postmenopausal female with urodynamic stress urinary *** patients had to fulfill a 3-day b.adder diary,overactive b.adder symptoms score,urine analysis,urodynamic study,and post-voiding residual urine measurement b. ab.ominal ultrasound preoperatively and at 3-month and 6-month ***:At 6-month follow-up,daytime frequency was reduced to 8%in Group A(increased to 21%in Group b.with a statistically significant difference b.tween b.th groups(p=0.009).At 6-month follow-up,nocturia was 8%in Group A(11%in Group b.with no statistically significant difference b.tween b.th groups(p=0.469).There was a statistically significant difference b.tween b.th groups as regards to urinary urgency at 6-month follow-up(p=0.024).There was a statistically significant difference in postoperative wound healing events as regards to cure,hyperemia,gapping,and wound infection 1 week after intervention b.tween b.th groups(p=0.008).No local or systemic side-effects were reported from local estrogen ***:Local vaginal estrogen treatment given to postmenopausal patients after midurethral sling procedures can reduce the symptoms o

关键词： Stressurinary incontinence Estrogen Midurethral sling Overactive b.adder symptom