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A trace formula for the vector Sturm-Liouville operator with a constant delay
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作者 LI Dan YANG Chuan-fu 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期213-222,共10页
In this work,the vector differential operator with a delay variable is studied and the regularized trace formula of the operator is obtained.
关键词 vector differential operator constant delay TRACE
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Accelerating Distributed Training of Large Concurrent-Branch Models through Bidirectional Pipeline Coordination
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作者 Zan Zong Yuyang Chen +4 位作者 Qi Zhang Daming Zhao Jianjiang Li Yijun Jing Jidong Zhai 《Tsinghua Science and Technology》 2025年第6期2638-2652,共15页
Large models have been widely used in the field of neural language processing,information retrieving,etc.With the development of the large models,not only is the parameter scale increased,but the model architecture ha... Large models have been widely used in the field of neural language processing,information retrieving,etc.With the development of the large models,not only is the parameter scale increased,but the model architecture has also become more complex.For example,the multi-modal transformer-based model mainly has concurrent branches,which we denoted as the concurrent branch model(CBM).Many CBMs have enlarged to tens of billions of parameters,and require distributed resources to train this kind of model.Existing distributed training systems cannot fully handle this type of model architecture because there are interactions between branches.Inspired by the unbalanced resource usage of pipeline parallelism,we prefer to organize different branches with a fine-grained bidirectional pipeline schedule of communication and computation.However,improper coordination between branches leads to idle time for computation and low training efficiency.In this paper,we present Flexpipe,a pipeline engine for c3oncurrent-branch models.We first introduce a branch-aware pipeline parallelism(BAPP)to make full use of the concurrent characteristic of the model architecture.Then,based on a multi-branch pipeline simulator,we propose an adaptive interaction coordinator,which facilitates the low-overhead branch interactions during the distributed model training.We evaluate our approach on popular concurrent branch models combined with modern training systems.Compared with the Chimera,the experiential results show that our method improves the end-to-end training throughput by 20%on average. 展开更多
关键词 parallel training system pipeline parallelism large model framework
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Lyapunov Optimizing Measures and Periodic Measures for C^(2) Expanding Maps
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作者 Wen Huang Leiye Xu Dawei Yang 《Acta Mathematica Sinica,English Series》 2025年第9期2259-2274,共16页
We prove that there exists an open and dense subset U in the space of C^(2) expanding self-maps of the circle T such that the Lyapunov minimizing measures of any T∈U are uniquely supported on a periodic orbit.This an... We prove that there exists an open and dense subset U in the space of C^(2) expanding self-maps of the circle T such that the Lyapunov minimizing measures of any T∈U are uniquely supported on a periodic orbit.This answers a conjecture of Jenkinson-Morris in the C^(2) topology. 展开更多
关键词 Lyapunov exponent expanding map ergodic optimization periodic orbit
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Numerical Modelling of Oblique Wave Interaction with Dual Curved-LEG Pontoon Floating Breakwaters
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作者 Jothika Palanisamy Chandru Muthusamy Higinio Ramos 《Computer Modeling in Engineering & Sciences》 2025年第11期2017-2038,共22页
This study investigates the performance of dual curved-leg pontoon floating breakwaters in finite water depth under the assumption of linear wave theory. The analysis is carried out for four different models of curved... This study investigates the performance of dual curved-leg pontoon floating breakwaters in finite water depth under the assumption of linear wave theory. The analysis is carried out for four different models of curvedleg geometries, which are combinations of convex and concave shapes. The models are classified as follows. Model-1: Seaside and leeside face concave, Model-2: Seaside and leeside face convex, Model-3: Seaside face convex and leeside face concave, and Model-4: Seaside face concave and leeside face convex. The Boundary Element Method is utilized in order to find a solution to the associated boundary value problem. The numerical results are validated against existing analytical and experimental data. Further, the study examines the wave reflection, wave transmission, and the hydrodynamic forces acting on the structure for different values of waves and structural parameters. Overall, the different dual curved-leg pontoon breakwaters are more effective, reducing wave transmission by over 15% and increasing wave reflection by more than 5% compared to traditional models. The study shows that the wave reflected by Model 1 significantly increased and attenuated the wave transmission relative to other models. The study found that the height of the curved-leg of Model 1 plays a critical role in blocking waves and redirecting the flow. More precisely, the present analysis concludes that the hydrodynamic performance of Model-1 presents an optimized breakwater design that outperforms the proposed models. 展开更多
关键词 Floating breakwater boundary element method reflection coefficient transmission coefficient hydrodynamic force surface elevation
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Optimizing the cooling efficiency of a convex spine fin with wetted characteristics beneficial in automotive components:an execution of Charlier polynomial collocation method
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作者 A.N.MALLIKARJUNA S.K.ABHILASHA +2 位作者 R.S.VARUN KUMAR F.GAMAOUN B.C.PRASANNAKUMARA 《Applied Mathematics and Mechanics(English Edition)》 2025年第8期1609-1630,共22页
Fins are extensively utilized in heat exchangers and various industrial applications as they are lightweight and can benefit in various systems,including electronic cooling devices and automotive components,owing to t... Fins are extensively utilized in heat exchangers and various industrial applications as they are lightweight and can benefit in various systems,including electronic cooling devices and automotive components,owing to their adaptable design.Furthermore,spine fins are introduced to improve performance in applications such as automotive radiators.They can be shaped in different ways and constructed from a collection of materials.Inspired by this,the present model examines the effects of internal heat generation and radiation-convection on the thermal distribution in a wetted convex-shaped spine fin.Using dimensionless terms,the proposed fin model involving a governing nonlinear ordinary differential equation(ODE)is transformed into a dimensionless form.The study uses the operational matrix with the Charlier polynomial collocation method(OMCCM)to ensure precise and computationally efficient numerical solutions for the dimensionless equation.In order to aid in the analysis of thermal performance,the importance of major parameters on the temperature profile is graphically illustrated.The main outcome of the study reveals that as the radiation-conductive,wet,and convective-conductive parameters increase,the heat transfer rate progressively improves.Conversely,the ambient temperature and internal heat generation parameters show an inverse relationship. 展开更多
关键词 FIN wet fin SPINE internal heat generation Charlier polynomial collocation method
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Spectral quasilinearization analysis of Casson fluid flow over a convectively heated inclined plate considering thermal dispersion and nonlinear thermal convection
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作者 Sathyendar Sreepada Surender Ontela Padigepati Naveen 《Chinese Physics B》 2025年第11期440-445,共6页
The present study investigates the influence of thermal dispersion on the natural convective flow of a Casson fluid along an inclined plate embedded in a non-Darcy porous medium.The governing equations,representing mo... The present study investigates the influence of thermal dispersion on the natural convective flow of a Casson fluid along an inclined plate embedded in a non-Darcy porous medium.The governing equations,representing momentum and energy conservations,are transformed into non-dimensional form using similarity transformations.To address the complexity of the resulting equations,a bivariate spectral quasilinearisation method is employed.The effects of relevant parameters—including thermal dispersion,Casson parameter,Biot number,Forchheimer number,inclination angle and nonlinear thermal convection parameter—are thoroughly examined.The results show that the drag coefficient and heat transfer rate increase with the nonlinear thermal convection parameter,Casson parameter and Biot number.In contrast,they decrease as the Forchheimer number and inclination angle increase.The velocity near the surface of the inclined plate increases with the Biot number,Casson parameter and nonlinear thermal convection parameter.However,it decreases farther from the plate.Additionally,the temperature of the Casson fluid increases with most parameters,except the Casson and nonlinear thermal convection parameters. 展开更多
关键词 Casson fluid thermal dispersion effect non-Darcy porous medium
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Certain Subclasses of Bi-univalent Functions Associated with(u,v)-Chebyshev Polynomials
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作者 Timilehin Gideon Shaba Sibel Yalcin +1 位作者 Gangadharan Murugusundaramoorthy Maslina Darus 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期429-442,共14页
For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Feket... For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Fekete-Szeg o functional. 展开更多
关键词 univalent functions Fekete-Szeg˝o inequalities analytic functions starlike and convex functions of some order bi-univalent functions coefficient bounds SUBORDINATION
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Surface-enhanced light harvesting over MOF-derived porous ZnO films for highly efficient QDs-based photoelectrochemical hydrogen generation
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作者 Yi Tao Zikun Tang +10 位作者 Linjie Xie Xiaolan Xu Wei Zhao Wenxuan Xu Dequan Bao Yihong Zhong Zhenqiu Gao Zhen Wen Kanghong Wang Hao Zhang Xuhui Sun 《Green Energy & Environment》 2025年第6期1270-1279,共10页
Rational design of porous metal oxide films that serve as not only the scaffolds for light absorbers but also the transfer layer of photo generated charges is essential for fabricating highly efficient photoanodes for... Rational design of porous metal oxide films that serve as not only the scaffolds for light absorbers but also the transfer layer of photo generated charges is essential for fabricating highly efficient photoanodes for photoelectrochemical(PEC)hydrogen generation.In this work,w report a facile one-step pyrolysis method which can convert Zn-based MOF to porous ZnO(m-ZnO)with rough surface and abundant oxygen vacancies(O_(v)).When incorporating core-shell quantum dots(QDs)as the light absorbers,the obtained photoanodes(m-ZnO@QDs)achieved outstanding PEC performance for hydrogen generation,exhibiting 1.6 times and 5.8 times higher saturated photocurrent density(J_(sc))than thos of conventional TiO_(2)@QDs and ZnO@QDs photoanodes,respectively.Comprehensive optical and electrochemical measurements reveal tha the rough surface of m-ZnO can significantly improve the light-harvesting capacity of corresponding photoanodes through surface-enhanced light scattering.Moreover,the O_(v)in m-ZnO facilitate the interfacial transfer of photogenerated electrons.Our findings indicate that the MOF are valuable precursors for the preparation of porous films,offering a promising route to develop high-performance QDs-based PEC devices. 展开更多
关键词 Photoelectrochemical hydrogen generation Metal organic framework Surface-enhanced light scattering Oxygen vacancies
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On Nonlinear Analysis for Multi-term Delay Fractional Differential Equations Under Hilfer Derivative
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作者 Dildar Ahmad Amjad Ali +2 位作者 Kamal Shah Bahaaeldin Abdalla Thabet Abdeljawad 《Communications on Applied Mathematics and Computation》 2025年第4期1516-1539,共24页
In this manuscript,a class of multi-term delay fractional differential equations(FDEs)under the Hilfer derivative is considered.Some newly updated results are established under boundary conditions.For the required res... In this manuscript,a class of multi-term delay fractional differential equations(FDEs)under the Hilfer derivative is considered.Some newly updated results are established under boundary conditions.For the required results,we utilize the fixed point theory and tools of the nonlinear functional analysis.Further keeping in mind the importance of stability results,we develop some adequate results about the said aspect.The Hyers-Ulam(H-U)-type concept is used to derive the required stability for the solution of the considered problem.Finally,by appropriate test problems,we justify our findings. 展开更多
关键词 Hilfer derivative Multi-term Existence results STABILITY
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Spherical Magnetic Fe-Alginate Microgels Fabricated by Droplet-Microfluidics Combining with an External Crosslinking Approach and the Study of Their pH Dependent Fe^(3+) Release Behaviors
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作者 Jie Chen Run-Yu Yu +3 位作者 ai-Qi Wang Zhe-Yu Zhang Arezoo Ardekani Yuan-Du Hu 《Chinese Journal of Polymer Science》 2025年第2期289-302,共14页
Due to the rapid development and potential applications of iron(Ⅲ)-alginate(Fe-Alg)microgels in biomedical as well as environmental engineering,this study explores the preparation and characterization of spherical Fe... Due to the rapid development and potential applications of iron(Ⅲ)-alginate(Fe-Alg)microgels in biomedical as well as environmental engineering,this study explores the preparation and characterization of spherical Fe-Alg microgels using droplet microfluidics combined with an external ionic crosslinking method.This study focused on the role of Fe^(3+)and examined its effects on the physical/chemical properties of microgels under different ionic conditions and reduced or oxidized states.The pH-dependent release behavior of Fe^(3+)from these microgels demonstrates their potential biomedical and environmental applications.Furthermore,the microgels can exhibit magnetism simply by utilizing in situ oxidation,which can be further used for targeted drug delivery and magnetic separation technologies. 展开更多
关键词 Fe-alginate microgels Droplet microfluidics In situ oxidation MAGNETISM
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Hydrodynamical characterization of nanofluidic flow driven by forced convection via a four-sided lid-driven cavity
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作者 M.USMAN M.HAMID +1 位作者 W.A.KHAN R.U.HAQ 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1383-1402,共20页
The unsteady magnetohydrodynamical(MHD)free convection flow of an incompressible,electrically conducting hybrid nanofluid within a vertical cylindrical geometry is investigated,incorporating the effects of thermal rad... The unsteady magnetohydrodynamical(MHD)free convection flow of an incompressible,electrically conducting hybrid nanofluid within a vertical cylindrical geometry is investigated,incorporating the effects of thermal radiation,viscous dissipation,and internal heat generation.The system is subjected to a time-periodic boundary temperature condition.The Laplace and finite Hankel transforms are used to derive the exact solutions for the velocity and temperature distributions.The effects of various key physical parameters,including the Richardson number,the Eckert number,the radiation parameter,the heat source parameter,and the nanoparticle volume fraction,are considered.The numerical results reveal that increasing the volume fraction significantly enhances the thermal conductivity and temperature,while the magnetic field intensity and viscous dissipation strongly influence the fluid motion and heat transport.Additionally,the pulsating boundary conditions produce distinct oscillatory behaviors in both the velocity and temperature fields.These findings provide important insights into optimizing the heat transfer performance in cylindrical systems such as electronic cooling modules and energy storage devices operating under dynamic thermal conditions. 展开更多
关键词 forced convection lid-driven cavity STREAMLINE finite element method
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MHD Thermosolutal Flow in Casson-Fluid Microchannels:Taguchi-GRA-PCA Optimization
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作者 Amina Mahreen Fateh Mebarek-Oudina +3 位作者 Amna Ashfaq Jawad Raza Sami Ullah Khan Hanumesh Vaidya 《Fluid Dynamics & Materials Processing》 2025年第11期2829-2853,共25页
Understanding the complex interaction between heat and mass transfer in non-Newtonian microflows is essential for the development and optimization of efficient microfluidic and thermal management systems.This study in... Understanding the complex interaction between heat and mass transfer in non-Newtonian microflows is essential for the development and optimization of efficient microfluidic and thermal management systems.This study investigates the magnetohydrodynamic(MHD)thermosolutal convection of a Casson fluid within an inclined,porous microchannel subjected to convective boundary conditions.The nonlinear,coupled equations governing momentum,energy,and species transport are solved numerically using the MATLAB bvp4c solver,ensuring high numerical accuracy and stability.To identify the dominant parameters influencing flow behavior and to optimize transport performance,a comprehensive hybrid optimization framework—combining a modified Taguchi design,Grey Relational Analysis(GRA),and Principal Component Analysis(PCA)—is proposed.This integrated strategy enables the simultaneous assessment of skin friction,Nusselt number,and Sherwood number,providing a rigorous multi-objective evaluation of system performance.Comparative validation with benchmark results from the literature confirms the accuracy and reliability of the present formulation and its numerical implementation.The results highlight the intricate coupling among flow slip,buoyancy effects,and convective transport mechanisms.Increased slip flow enhances axial velocity,while a higher solutal Biot number intensifies concentration gradients near the channel walls.Conversely,a lower thermal Biot number diminishes the temperature field,indicating weaker heat transfer across the boundaries.PCA results reveal that the first principal component(PC1)accounts for most of the system variance,demonstrating the dominant influence of coupled flow and transport parameters on overall system performance. 展开更多
关键词 Microchannel flow casson fluid MAGNETOHYDRODYNAMICS convective boundary conditions taguchi method grey relational analysis principal component analysis thermosolutal convection
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Incorporating Fully Fuzzy Logic in Multi-Objective Transshipment Problems:A Study of Alternative Path Selection Using LR Flat Fuzzy Numbers
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作者 Vishwas Deep Joshi Priya Agarwal +4 位作者 Lenka Cepová Huda Alsaud Ajay Kumar B.Swarna Ashish Kumar 《Computer Modeling in Engineering & Sciences》 2025年第7期969-1011,共43页
In a world where supply chains are increasingly complex and unpredictable,finding the optimal way to move goods through transshipment networks is more important and challenging than ever.In addition to addressing the ... In a world where supply chains are increasingly complex and unpredictable,finding the optimal way to move goods through transshipment networks is more important and challenging than ever.In addition to addressing the complexity of transportation costs and demand,this study presents a novel method that offers flexible routing alternatives to manage these complexities.When real-world variables such as fluctuating costs,variable capacity,and unpredictable demand are considered,traditional transshipment models often prove inadequate.To overcome these challenges,we propose an innovative fully fuzzy-based framework using LR flat fuzzy numbers.This framework allows for more adaptable and flexible decision-making in multi-objective transshipment situations by effectively capturing uncertain parameters.To overcome these challenges,we develop an innovative,fully fuzzy-based framework using LR flat fuzzy numbers to effectively capture uncertainty in key parameters,offering more flexible and adaptive decision-making in multi-objective transshipment problems.The proposed model also presents alternative route options,giving decisionmakers a range of choices to satisfy multiple requirements,including reducing costs,improving service quality,and expediting delivery.Through extensive numerical experiments,we demonstrate that the model can achieve greater adaptability,efficiency,and flexibility than standard approaches.This multi-path structure provides additional flexibility to adapt to dynamic network conditions.Using ranking strategies,we compared our multi-objective transshipment model with existing methods.The results indicate that,while traditional methods such as goal and fuzzy programming generate results close to the anti-ideal value,thus reducing their efficiency,our model produces solutions close to the ideal value,thereby facilitating better decision making.By combining dynamic routing alternatives with a fully fuzzybased approach,this study offers an effective tool to improve decision-making and optimize complex networks under real-world conditions in practical settings.In this paper,we utilize LINGO 18 software to solve the provided numerical example,demonstrating the effectiveness of the proposed method. 展开更多
关键词 Multi-objective transshipment problem LR flat fuzzy numbers fully fuzzy optimization flexible routing solutions ranking approach
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A Numerical Study of the Caputo Fractional Nonlinear Rossler Attractor Model via Ultraspherical Wavelets Approach
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作者 Ashish Raya Priya Dogra +2 位作者 Sabri T.M.Thabet Imed Kedim Miguel Vivas-Cortez 《Computer Modeling in Engineering & Sciences》 2025年第5期1895-1925,共31页
The Rössler attractor model is an important model that provides valuable insights into the behavior of chaotic systems in real life and is applicable in understanding weather patterns,biological systems,and secur... The Rössler attractor model is an important model that provides valuable insights into the behavior of chaotic systems in real life and is applicable in understanding weather patterns,biological systems,and secure communications.So,this work aims to present the numerical performances of the nonlinear fractional Rössler attractor system under Caputo derivatives by designing the numerical framework based on Ultraspherical wavelets.The Caputo fractional Rössler attractor model is simulated into two categories,(i)Asymmetric and(ii)Symmetric.The Ultraspherical wavelets basis with suitable collocation grids is implemented for comprehensive error analysis in the solutions of the Caputo fractional Rössler attractor model,depicting each computation in graphs and tables to analyze how fractional order affects the model’s dynamics.Approximate solutions obtained through the proposed scheme for integer order are well comparable with the fourth-order Runge-Kutta method.Also,the stability analyses of the considered model are discussed for different equilibrium points.Various fractional orders are considered while performing numerical simulations for the Caputo fractional Rössler attractor model by using Mathematica.The suggested approach can solve another non-linear fractional model due to its straightforward implementation. 展开更多
关键词 Fractional Rössler attractor ultraspherical wavelets caputo derivative error analysis stability analysis
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Mathematical Modeling of Leukemia within Stochastic Fractional Delay Differential Equations
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作者 Ali Raza Feliz Minhós +1 位作者 Umar Shafique Muhammad Mohsin 《Computer Modeling in Engineering & Sciences》 2025年第6期3411-3431,共21页
In 2022,Leukemia is the 13th most common diagnosis of cancer globally as per the source of the International Agency for Research on Cancer(IARC).Leukemia is still a threat and challenge for all regions because of 46.6... In 2022,Leukemia is the 13th most common diagnosis of cancer globally as per the source of the International Agency for Research on Cancer(IARC).Leukemia is still a threat and challenge for all regions because of 46.6%infection in Asia,and 22.1%and 14.7%infection rates in Europe and North America,respectively.To study the dynamics of Leukemia,the population of cells has been divided into three subpopulations of cells susceptible cells,infected cells,and immune cells.To investigate the memory effects and uncertainty in disease progression,leukemia modeling is developed using stochastic fractional delay differential equations(SFDDEs).The feasible properties of positivity,boundedness,and equilibria(i.e.,Leukemia Free Equilibrium(LFE)and Leukemia Present Equilibrium(LPE))of the model were studied rigorously.The local and global stabilities and sensitivity of the parameters around the equilibria under the assumption of reproduction numbers were investigated.To support the theoretical analysis of the model,the Grunwald Letnikov Nonstandard Finite Difference(GL-NSFD)method was used to simulate the results of each subpopulation with memory effect.Also,the positivity and boundedness of the proposed method were studied.Our results show how different methods can help control the cell population and give useful advice to decision-makers on ways to lower leukemia rates in communities. 展开更多
关键词 Leukemia disease stochastic fractional delayed model stability analysis Grunwald Letnikov Nonstandard Finite Difference(GL-NSFD) computational methods
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Numerical Analysis of Entropy Generation in Joule Heated Radiative Viscous Fluid Flow over a Permeable Radially Stretching Disk
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作者 Tahir Naseem Fateh Mebarek-Oudina +3 位作者 Hanumesh Vaidya Nagina Bibi Katta Ramesh Sami Ullah Khan 《Computer Modeling in Engineering & Sciences》 2025年第4期351-371,共21页
Maximizing the efficiency of thermal engineering equipment involves minimizing entropy generation,which arises from irreversible processes.This study examines thermal transport and entropy generation in viscous flow o... Maximizing the efficiency of thermal engineering equipment involves minimizing entropy generation,which arises from irreversible processes.This study examines thermal transport and entropy generation in viscous flow over a radially stretching disk,incorporating the effects of magnetohydrodynamics(MHD),viscous dissipation,Joule heating,and radiation.Similarity transformations are used to obtain dimensionless nonlinear ordinary differential equations(ODEs)from the governing coupled partial differential equations(PDEs).The converted equations are then solved by using the BVP4C solver in MATLAB.To validate the findings,the results are compared with previously published studies under fixed parameter conditions,demonstrating strong agreement.Various key parameters are analyzed graphically to assess their impact on velocity and temperature distributions.Additionally,Bejan number and entropy generation variations are presented for different physical parameters.The injection parameter(S<0)increases the heat transfer rate,while the suction parameter(S>0)reduces it,exhibiting similar effects on fluid velocity.The magnetic parameter(M)effectively decreases entropy generation within the range of approximately 0≤η≤0.6.Beyond this interval,its influence diminishes as entropy generation values converge,with similar trends observed for the Bejan number.Furthermore,increased thermal radiation intensity is identified as a critical factor in enhancing entropy generation and the Bejan number. 展开更多
关键词 Partial differential equations modeling stretched surface joule heating viscous dissipation radiation suction/injection
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Spectral Quasi-Linearization Study of Variable Viscosity Casson Nanofluid Flow under Buoyancy and Magnetic Fields
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作者 B.Rajesh Fateh Mebarek-Oudina +4 位作者 N.Vishnu Ganesh Qasem M.Al-Mdallal Sami Ullah Khan Murali Gundagnai Hillary Muzara 《Frontiers in Heat and Mass Transfer》 2025年第4期1243-1260,共18页
The behavior of buoyancy-driven magnetohydrodynamic(MHD)nanofluid flows with temperature-sensitive viscosity plays a pivotal role in high-performance thermal systems such as electronics cooling,nuclear reactors,and me... The behavior of buoyancy-driven magnetohydrodynamic(MHD)nanofluid flows with temperature-sensitive viscosity plays a pivotal role in high-performance thermal systems such as electronics cooling,nuclear reactors,and metallurgical processes.This study focuses on the boundary layer flow of a Casson-based sodium alginate Fe3O4 nanofluid influenced by magnetic field-dependent viscosity and thermal radiation,as it interacts with a vertically stretching sheet under dissipative conditions.To manage the inherent nonlinearities,Lie group transformations are applied to reformulate the governing boundary layer equations into similarity forms.These reduced equations are then solved via the Spectral Quasi-Linearization Method(SQLM),ensuring high accuracy and computational efficiency.The analysis comprehensively explores the impact of key parameters-including mixed convection intensity,magnetic field strength,Casson fluid properties,temperature-dependent viscosity,thermal radiation,and viscous dissipation(Eckert number)-on flow characteristics and heat transfer rates.Findings reveal that increasing magnetic field-dependent viscosity diminishes both skin friction and thermal transport,while buoyancy effects enhance heat transfer but lower shear stress on the surface.This work provides critical insights into controlling heat and momentum transfer in Casson nanofluids,advancing the design of thermal management systems involving complex fluids under magnetic and buoyant forces. 展开更多
关键词 Casson nanofluid buoyancy-driven flow temperature-dependent viscosity magnetic field effects thermal radiation spectral quasi-linearization method stretching sheet
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Applications of variable thermal features for the bioconvective flow of Jeffrey nanofluids due to stretching surface with masssuction effects:Cattaneo-Christov model
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作者 S.U.KHAN M.GARAYEV +4 位作者 ADNAN K.RAMESH M.EL MELIGY D.ABDUVALIEVA M.I.KHAN 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期391-402,共12页
The thermal nanofluids have garnered widespread attention for their use in multiple thermal systems,including heating processes,sustainable energy,and nuclear reactions.Research on nanofluids has revealed that the the... The thermal nanofluids have garnered widespread attention for their use in multiple thermal systems,including heating processes,sustainable energy,and nuclear reactions.Research on nanofluids has revealed that the thermal efficiencies of such materials are adversely affected by various thermal features.The purpose of the current work is to demonstrate the thermal analysis of Jeffrey nanofluids with the suspension of microorganisms in the presence of variable thermal sources.The variable effects of thermal conductivity,Brownian diffusivity,and motile density are utilized.The investigated model also reveals the contributions of radiation phenomena and chemical reactions.A porous,saturated,moving surface with a suction phenomenon promotes flow.The modeling of the problem is based on the implementation of the Cattaneo-Christov approach.The convective thermal constraints are used to promote the heat transfer features.A simplified form of the governing model is treated with the assistance of a shooting technique.The physical effects of different parameters for the problem are presented.The current problem justifies its applications in heat transfer,coating processes,heat exchangers,cooling systems in microelectronics,solar systems,chemical processes,etc. 展开更多
关键词 Jeffrey nanofluid bioconvection effect variable thermal consequence chemical reaction numerical simulation
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一类分支过程的收敛性 被引量:2
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作者 林祥 Zhang Hanjun 《数学物理学报(A辑)》 CSCD 北大核心 2006年第6期897-905,共9页
随机稳定性是各种随机模型中的至关重要的问题,随机稳定性中的关键问题是找出过程遍历,指数遍历和强遍历的准则.该文对一类重要的分支过程给出了过程指数遍历及强遍历的条件.在证明中主要应用了几种不同的比较方法,从该文的结果可以看... 随机稳定性是各种随机模型中的至关重要的问题,随机稳定性中的关键问题是找出过程遍历,指数遍历和强遍历的准则.该文对一类重要的分支过程给出了过程指数遍历及强遍历的条件.在证明中主要应用了几种不同的比较方法,从该文的结果可以看出,这种方法是有效的,因而在其它情形中也是非常有意义的.而且所得结果的概率意义也是十分清楚的. 展开更多
关键词 随机稳定性 遍历 指数遍历 强遍历
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Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects 被引量:22
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作者 Yang Wang Zheng-wei Li +2 位作者 Min Luo Ya-jun Li Ke-qiang Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第6期965-971,共7页
The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data com... The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group, followed by the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group. These results indicate that bridging 10-mm conduit + bone marrow mesenchymal stem sciatic nerve defects with a polylactic glycolic acid cells + extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better regeneration was found with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel grafts than with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells grafts and the autologous nerve grafts. 展开更多
关键词 nerve regeneration peripheral nerve injury rabbits sciatic nerve injury autologous nerye repair polylactic glycolic acid conduit extracellular matrix gel grafting stress relaxation creep viscoelasticity HISTOMORPHOLOGY ELECTROPHYSIOLOGY neural regeneration
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