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AI-Assisted Hybrid Solver for Skin Friction and Sherwood Number Prediction in Eyring–Prandtl Nanofluid Flow over a Riga Plate
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作者 Yasir Nawaz Nabil Kerdid +1 位作者 Muhammad Shoaib Arif Mairaj Bibi 《Computer Modeling in Engineering & Sciences》 2026年第2期586-623,共38页
A high-order hybrid numerical framework is developed by coupling a three-stage exponential time integrator with a Runge–Kutta scheme for the efficient solution of partial differential equations involving first-order ... A high-order hybrid numerical framework is developed by coupling a three-stage exponential time integrator with a Runge–Kutta scheme for the efficient solution of partial differential equations involving first-order time derivatives.The proposed scheme attains third-order temporal accuracy and is rigorously validated through stability and convergence analyses for both scalar and coupled systems.Its effectiveness is demonstrated by simulating unsteady Eyring-Prandtl non-Newtonian nanofluid flow over a Riga plate with coupled heat and mass transfer under electromagnetic actuation.The physical model accounts for Brownian motion and thermophoresis,and the nanofluid considered is a Prandtl-type non-Newtonian base fluid containing suspended nanoparticles,with heat and mass transport governed by coupled momentum,energy,and concentration equations.Numerical simulations are performed over practically relevant parameter ranges,with the Reynolds number fixed at Re=5 and the Prandtl number set to Pr=3 to represent moderate inertial and thermal diffusion effects typical of nanofluid transport systems.To enhance computational efficiency,an artificial neural network(ANN)-based surrogate model is developed to predict the skin friction coefficient and local Sherwood number as functions of Reynolds number,Prandtl number,Schmidt number,Brownian motion,and thermophoresis parameters.The training dataset is generated entirely from high-fidelity numerical simulations produced by the proposed hybrid scheme.The data are systematically partitioned into 70%for training,15%for validation,and 15%for testing,ensuring reliable generalization.Regression analysis yields a near-unity correlation coefficient(R≈0.99),while error histograms exhibit tightly clustered residuals around zero,confirming high predictive accuracy.Furthermore,a benchmark convergence study using Stokes’first problem demonstrates that the proposed scheme consistently achieves lower global error norms than the classical Runge–Kutta method for identical spatial and temporal resolutions.Overall,this study introduces a novel computational intelligence framework that integrates high-order numerical solvers with machine learning,offering a robust and time-efficient tool for advanced modeling and real-time prediction of non-Newtonian nanofluid transport phenomena under electromagnetic flow control. 展开更多
关键词 Eyring-Prandtl nanofluid riga plate heat and mass transfer hybrid numerical scheme neural network prediction
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Neuro-Fuzzy Computational Dynamics of Reactive Hybrid Nanofluid Flow Inside a Squarely Elevated Riga Tunnel with Ramped Thermo-Solutal Conditions under Strong Electromagnetic Rotation
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作者 Asgar Ali Nayan Sardar +1 位作者 Poly Karmakar Sanatan Das 《Computer Modeling in Engineering & Sciences》 2025年第12期3563-3626,共64页
Hybrid nanofluids have gained significant attention for their superior thermal and rheological characteristics,offering immense potential in energy conversion,biomedical transport,and electromagnetic flow control syst... Hybrid nanofluids have gained significant attention for their superior thermal and rheological characteristics,offering immense potential in energy conversion,biomedical transport,and electromagnetic flow control systems.Understanding their dynamic behavior under coupled magnetic,rotational,and reactive effects is crucial for the development of efficient thermal management technologies.This study develops a neuro-fuzzy computational framework to examine the dynamics of a reactive Cu–TiO_(2)–H_(2)Ohybrid nanofluid flowing through a squarely elevated Riga tunnel.The governing model incorporates Hall and ion-slip effects,thermal radiation,and first-order chemical reactions under ramped thermo-solutal boundary conditions and rotational electromagnetic forces.Closed-form analytical solutions are derived via the Laplace transform method to describe the transient velocity,temperature,and concentration fields.To complement and validate the analytical model,an artificial neural network(ANN)optimized using the Levenberg–Marquardt backpropagation algorithm(ANN-LMBPA)is trained on datasets generated in Mathematica.Regression and error analyses confirm the model’s predictive robustness,with mean squared errors ranging between 10^(-4) and 10^(-9).In addition,an Adaptive Neuro-Fuzzy Inference System(ANFIS)is developed to estimate the heat transfer rate(HTR),achieving aminimal RMSE of 0.011012 for the heat transfer coefficient(HTC).The findings reveal that rotational motion and Hall–ion slip effects suppress primary velocity but enhance secondary flow,while the modified Hartmann number(Lorentz force)accelerates both components.Thermal radiation increases fluid temperature,whereas higher Schmidt numbers and reaction rates diminish solute concentration.The HTR decreases with increasing radiation and nanoparticle volume fraction,while the mass transfer rate(MTR)improves under stronger chemical reactivity.Overall,the proposed hybrid analytical–AI framework demonstrates high accuracy and efficiency,offering valuable insights for the design and optimization of electromagnetic nanofluid systems in advanced thermal and process engineering applications. 展开更多
关键词 Neuro-fuzzy computational dynamics reactive hybrid nanofluids strong electromagnetic rotation squarely elevated riga tunnel ramped thermo-solutal conditions Laplace transform technique
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Riga’s病89例
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作者 王淑敏 吴国照 苏健 《实用儿科临床杂志》 CAS CSCD 1997年第5期358-358,共1页
关键词 riga氏病 口腔溃疡 婴幼儿 病例报告 创伤性溃病
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新生儿Riga氏病1例
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作者 马柱 周校燕 《西部医学》 2003年第2期176-176,共1页
关键词 新生儿 riga氏病 临床表现 口腔溃疡 病例
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Investigations of Viscous Dissipation in Stagnation Point Flow Past a Stretchable Riga Wall: Modern Analysis of Heat Transport
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作者 Aisha Anjum N.A.Mir +2 位作者 M.Farooq M.Javed S.Ahmad 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第4期377-383,共7页
This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out... This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out in Cattaneo-Christov diffusion analysis for the ?rst time in this letter. As a result of Cattaneo-Christov model, some extra terms of viscous dissipation are appeared in the energy equation. These extra terms of viscous dissipation are missing in the literature. On the utilization of suitable transformations, the equations governing the problem are reduced under the boundary layer approximation into the non-linear and dimensionless ordinary differential equations. Convergent approach is utilized to solve the dimensionless governing equations. The solution thus acquired is used to highlight the effects of emerging parameters on velocity distribution and ?uid's temperature through the graphs. Features of the drag force(or skin friction co-e?cient) are graphically interpreted. It is noticed that the presence of modi?ed Hartman number helps to reduce the ?uid's temperature but enhances the velocity pro?le. Further an enlargement in the value of thermal time relaxation parameter helps to decrease the temperature distribution. 展开更多
关键词 STAGNATION point Cattaneo-Christov theory riga plate linear STRETCHING VISCOUS DISSIPATION
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通过具有速度滑移和辐射效应的可渗透拉伸/收缩Riga板的驻点流动和热传导(英文)
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作者 Nor Ain Azeany Mohd NASIR Anuar ISHAK Ioan POP 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2019年第4期290-299,共10页
目的:1.通过分析Riga板的抽吸效应来控制流体运动和减少摩擦力和压力阻力;2.利用磁场的速度滑移效应来控制流体的流速;3.基于辐射原理控制热传导并减小阻力。创新点:1.本研究可应用于核电厂、飞机、潜艇以及卫星等设施中推进装置的设计... 目的:1.通过分析Riga板的抽吸效应来控制流体运动和减少摩擦力和压力阻力;2.利用磁场的速度滑移效应来控制流体的流速;3.基于辐射原理控制热传导并减小阻力。创新点:1.本研究可应用于核电厂、飞机、潜艇以及卫星等设施中推进装置的设计;2.本研究可用于防止边界层分离以减少湍流的产生。方法:1.构建基于偏微分方程的数理模型;2.利用相似变换法将偏微分方程简化为常微分方程;3.利用Matlab内置求解器bvp4c对常微分方程组进行数值求解;4.基于求解结果讨论稳定性。结论:1.对于拉伸/收缩两种情形的Riga板问题都存在对偶解;2.数值求解结果显示表面摩擦系数和表面传热率均会随着吸力的增大而增大,而随拉伸/收缩参数?的增大而减小;3.上支解的努塞尔数增大而下支解减小;4.辐射会提高边界层内的温度,而增强滑移效应则会提高流速同时降低边界层温度;5.只有上支解是长期稳定的。 展开更多
关键词 riga 驻点流动 热传导 收缩薄片 对偶解
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Evaluation of Local Scale PM Pollution Levels in Typical Street Canyon in Riga
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作者 Iveta Steinberga Janis Bikshe Jr. +2 位作者 Karlis Kundzins Janis Kleperis Janis Bikshe 《Journal of Environmental Protection》 2013年第9期956-963,共8页
The present study describes long term PM10 and PM2.5 changes in typical street canyon with particular emphasis on seasonal, diurnal variations in context with meteorological data. In order to understand PM10 pollution... The present study describes long term PM10 and PM2.5 changes in typical street canyon with particular emphasis on seasonal, diurnal variations in context with meteorological data. In order to understand PM10 pollution sources during 28 April 2007-31 December 2007, chemical composition measurements were done with particular emphasis on heavy metals (As, Cd, Ni, and Pb), crustal material (Ca, Mg, Na, and K) and anions (sulphates, nitrates, chlorides). Meteorological data used for this evolutional analysis were measured close to traffic related stations and several meteorological parameters were analyzed in relation to particulate measurements. Keep in mind that atmospheric aerosols are generally hydroscopic. Relative humidity which plays very important role in rain/snow and humidity impact are analyzed. 展开更多
关键词 Air POLLUTION PM riga STREET CANYON Source-Apportionment
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Casson hybrid nanofluid flow over a Riga plate for drug deliveryapplications with double diffusion
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作者 Abeer S.Alnahdi Taza Gul 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期311-320,共10页
Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity.Heat exchangers,cooling systems and other thermal management syste... Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity.Heat exchangers,cooling systems and other thermal management systems are ideal for use with Casson fluids.Precise control of the flow and release of medication is necessary when using Casson fluids in drug delivery systems because of their unique rheological properties.Nanotechnology involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted delivery.In this study,to create a hybrid nanofluid,both single-walled carbon nanotubes(SWCNTs)and multi-walled carbon nanotubes(MWCNTs)are dispersed in a Casson fluid with Fourier’s and Fick’s laws assumptions.The Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by the carbon nanotubes.Our objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga plate.The Darcy-Forchheimer model is also used to account for the impact of the porous medium near the stretching plate.Both linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the nanofluid.In addition,the homotopy analysis method is utilized to address the model problem.The outcomes are discussed and deliberated based on drug delivery applications.These findings shed valuable light on the flow characteristics of a Casson hybrid nanofluid comprising SWCNTs and MWCNTs.It is observed that the incorporation of carbon nanotubes makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties. 展开更多
关键词 carbon nanotubes(CNTs) riga plate Casson fluid with Fourier’s and Fick’s laws analytical solutions
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Impulsively Started Horizontal Riga Plate Embedded in Unsteady Casson Fluid Flow with Rotation
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作者 Sonia Nasrin Rabindra Nath Mondal Md. Mahmud Alam 《Journal of Applied Mathematics and Physics》 2020年第9期1861-1876,共16页
This article is based on the impulsively started horizontal Riga plate in two dimensional unsteady Casson fluid flows with rotation. The plate starts abruptly from the rest relative to the rotating fluids moving with ... This article is based on the impulsively started horizontal Riga plate in two dimensional unsteady Casson fluid flows with rotation. The plate starts abruptly from the rest relative to the rotating fluids moving with uniform acceleration in its plane. Numerical solutions are acquired by using explicit finite difference method and estimated results have been gained for various values of the Rotational parameter, modified Hartmann number, Prandtl number, Radiative parameter, Eckert number, Heat source parameter, Schmidt number, and the Soret number. Both the Compaq visual FORTRAN 6.6a and MATLAB R2015a tools have been used to find the numerical solutions and the graphical presentation. The Skin friction, Nusselt number and Sherwood number have been computed and the effects of some pertinent parameters on various distributions are discussed briefly and presented graphically. 展开更多
关键词 Casson Fluid riga Plate Explicit Finite Difference and Rotation
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冬季航行里加RIGA港介绍
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作者 施振东 孙友林 《海运科技》 1994年第7期1-4,共4页
关键词 港口 里加riga 航行 冬季
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Novel Analysis of SiO_(2)+ZnO+MWCN T-Ternary Hybrid Nanofluid Flow in Electromagnetic Squeezing Systems
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作者 Muhammad Hamzah Muhammad Ramzan +3 位作者 Abdulrahman A.Almehizia Ibrahim Mahariq Laila A.Al-Essa Ahmed S.Hassan 《Computer Modeling in Engineering & Sciences》 2026年第1期604-626,共23页
The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a wat... The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a water-ethylene glycol base fluid between two perforated squeezing Riga plates.This problem is important because it helps us understand the complicated connections between magnetic fields,nanofluid dynamics,and heat transport,all of which are critical for designing thermal management systems.These findings are especially useful for improving the design of innovative cooling technologies in electronics,energy systems,and healthcare applications.No prior study has been done on the theoretical study of the flow of ternary nanofluid(SiO_(2)+ZnO+MWCNT/Water−EthylGl ycol,(60∶40))past a pierced squeezed Riga plates using the boundary value problem solver 4th-order collocation(BVP4C)numerical approach to date.So,the current work has been carried out to fill this gap,and the core purpose of this study is to explore the aspects that enhance the heat transfer of base fluids(H_(2)O/EG)suspended with three nanomaterials SiO_(2),ZnO,and MWCNT.The Riga plates introduce electromagnetic forcing through an embedded array of magnets and electrodes,generating Lorentz forces to regulate the flow.The squeezing effect introduces dynamic boundary movement,which enhances mixing;however,permeability,due to porosity,replicates the true material limits.Similarity transformations of the Navier-Stokes and energy equations result in a highly nonlinear set of ordinary differential equations that govern momentum and thermal energy transport.The subsequent boundary value problem is solved utilizing the BVP4C numerical approach.The study observes the impact of magnetic parameters,squeezing velocity,solid volume percentages of the three nanoparticles,and porous medium factors on velocity and temperature fields.Results show that magnetic fields reduce the velocity profile by 6.75%due to increased squeezing and medium effects.Tri-hybrid nanofluids notice a 9%rise in temperature with higher thermal radiation. 展开更多
关键词 Ternary hybrid nanofluid thermal radiation MATLAB riga plates porous medium squeezing flow electromagnetic field
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基于词汇化随机文法模型的RNA二级结构预测 被引量:4
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作者 唐四薪 周勇 邹赛 《计算机工程与科学》 CSCD 北大核心 2009年第3期128-131,共4页
针对经典的随机文法模型预测RNA二级结构存在精度不高的问题,本文给出了一种词汇化随机文法模型预测RNA二级结构的方法。首先,用最大熵模型获取RNA序列中的词条信息,通过Viterbi算法搜索每个词条被标注为某种二级结构类型的最大概率;然... 针对经典的随机文法模型预测RNA二级结构存在精度不高的问题,本文给出了一种词汇化随机文法模型预测RNA二级结构的方法。首先,用最大熵模型获取RNA序列中的词条信息,通过Viterbi算法搜索每个词条被标注为某种二级结构类型的最大概率;然后,将这些词条信息作为先验信息在随机文法模型训练过程中引入,从而加快对二级结构的搜索过程,提高准确率。 展开更多
关键词 RNA二级结构 随机文法 词汇化 结构预测
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西藏措勤县日阿铜矿床成矿地质条件及成矿过程浅析 被引量:1
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作者 王强 孙燕 +3 位作者 赵志强 赵涵 何佳乐 王瑜亮 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2012年第3期229-235,共7页
西藏自治区是我国未来重要的铜矿基地,有着重要的战略地位。日阿铜矿床位于冈底斯山脉北缘,地处隆格尔-工布江达断隆带,地质工作程度较低。笔者通过研究矿床的地质特征,从地层、构造、岩浆岩、成岩成矿时代等方面分析了矿床形成的地质条... 西藏自治区是我国未来重要的铜矿基地,有着重要的战略地位。日阿铜矿床位于冈底斯山脉北缘,地处隆格尔-工布江达断隆带,地质工作程度较低。笔者通过研究矿床的地质特征,从地层、构造、岩浆岩、成岩成矿时代等方面分析了矿床形成的地质条件,根据该矿床经历的地质作用、矿石构造以及矿物组合特征,认为矿床为矽卡岩型铜矿,主要成矿作用经历了岩浆热液成矿期和表生风化期,其中岩浆热液成矿期为主要成矿期,可进一步分为矽卡岩阶段,氧化物阶段,石英硫化物阶段等,并在此基础上总结出日阿矽卡岩型铜矿床的成矿模式。 展开更多
关键词 西藏 日阿铜矿床 成矿地质条件 成矿过程
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巴尔干联合思想与实践的历史考察 被引量:2
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作者 徐刚 《俄罗斯学刊》 2018年第4期47-61,共15页
近代以降,特别是1878年《柏林条约》签署以来,巴尔干地区一直是个多事之域。实际上,在巴尔干地区内部,不同民族、不同身份属性的人们在追求民族解放和国家独立的进程中相继提出诸多形态的巴尔干联合思想,践行巴尔干联盟或联邦运动。由... 近代以降,特别是1878年《柏林条约》签署以来,巴尔干地区一直是个多事之域。实际上,在巴尔干地区内部,不同民族、不同身份属性的人们在追求民族解放和国家独立的进程中相继提出诸多形态的巴尔干联合思想,践行巴尔干联盟或联邦运动。由于内部多样性、异质性和对立性突出,特别是缺乏对巴尔干联合事业的共同担当,加上大国和大国集团的干扰与反对,巴尔干革命民主主义者、社会主义者(包括社会民主党人和共产党人)以及二轨活动家的思想主张和实践运动或未能实现,或以失败告终。尽管如此,这些属于巴尔干地区积极和进步的一面,诠释了"巴尔干人的巴尔干"理念及其实践的困难,为理解和还原客观的巴尔干近现代史提供了丰富的素材和另类的视角。同样,消除地区内部分裂和对立并非朝夕之功,南斯拉夫解体带来的负面遗产将长期留存,欧洲一体化事业遭遇多面冲击,冷战结束后巴尔干国家集体选择融入欧洲大家庭以实现地区合作、谅解与进步的道路仍将漫长。 展开更多
关键词 巴尔干联合 里加斯 巴尔干联邦 巴尔干会议 南保联邦
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新型滴灌双向流道参数化设计研究
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作者 王新端 白丹 +1 位作者 郭霖 何靖 《西安理工大学学报》 北大核心 2017年第3期321-325,332,共6页
针对双向流道挡水件中后部存在较大低流速区的问题,对原有结构改进后提出新型双向流道结构。为了研究新型双向流道结构参数对其水力性能的影响,选取5个关键参数作为试验因素。采用均匀试验设计方法,设计8组试验方案制作流道样件,分别在... 针对双向流道挡水件中后部存在较大低流速区的问题,对原有结构改进后提出新型双向流道结构。为了研究新型双向流道结构参数对其水力性能的影响,选取5个关键参数作为试验因素。采用均匀试验设计方法,设计8组试验方案制作流道样件,分别在不同水头压力下测得各流道样件出流量,计算其流态指数及流量系数。采用通径分析定性地分析各结构参数对水力性能的影响效应。利用多元线性回归分析,建立了流态指数和流量系数与5个结构参数之间的量化模型,并通过试验验证了其准确性和可行性。结果表明,挡水件底部高度是流态指数的主要增进因子,而分水件与上挡水外壁的距离是其主要限制因子;挡水件垂直部分高度是流量系数的主要决策变量,且各参数都为增进因子。建立的量化关系模型效果显著,准确性高,定量地揭示了流道结构参数与其水力性能的关系,对设计性能良好的双向流道有一定指导意义。 展开更多
关键词 滴灌 双向流道 水力性能 参数化设计 通径分析 回归分析
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求解最大子团的随机抽样免疫遗传算法
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作者 周本达 陈明华 《计算机工程与应用》 CSCD 北大核心 2011年第16期40-42,107,共4页
针对遗传算法在最大子团求解中保持群体多样性能力不足、早熟、耗时长、成功率低等缺陷,利用随机抽样方法对交叉操作进行重新设计,结合免疫机理定义染色体浓度,设计克隆选择策略,提出了求解最大子团问题的随机抽样免疫遗传算法。用仿真... 针对遗传算法在最大子团求解中保持群体多样性能力不足、早熟、耗时长、成功率低等缺陷,利用随机抽样方法对交叉操作进行重新设计,结合免疫机理定义染色体浓度,设计克隆选择策略,提出了求解最大子团问题的随机抽样免疫遗传算法。用仿真算例说明了新算法在解的质量、收敛速度等各项指标上均有提高,且不比DLS-MC、QUALEX等经典搜索算法差,对某些算例还得到了更好解。 展开更多
关键词 最大团问题 遗传算法 随机抽样 人工免疫系统 随机抽样免疫遗传算法
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里加周期内欧盟促进职业教育与培训改革的路径选择及启示 被引量:3
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作者 王琳 徐涵 《现代教育管理》 CSSCI 北大核心 2022年第1期119-128,共10页
欧盟各国于2015年在拉脱维亚首都里加共同确定了里加周期(2015—2020年)职业教育与培训(VET)改革的五个优先领域(即里加结论)。欧盟各国根据里加结论分别在职业教育与培训政策法律保障、多元利益主体协同合作、职业教育质量保障与评估... 欧盟各国于2015年在拉脱维亚首都里加共同确定了里加周期(2015—2020年)职业教育与培训(VET)改革的五个优先领域(即里加结论)。欧盟各国根据里加结论分别在职业教育与培训政策法律保障、多元利益主体协同合作、职业教育质量保障与评估标准、职业教育关键能力、职业教育教师专业化发展五个方面采取了不同的政策措施,以促进本国职业教育与培训(VET)的发展,加强欧盟成员国内部职业教育与培训(VET)的合作。借鉴其经验,建议设计符合我国国情的现代学徒制、建立企业参与学徒制的促进机制,促进多部门以及利益相关者之间的合作和交流、加强职业教育与劳动力市场需求的契合度、构建我国职业教育关键能力模型。 展开更多
关键词 欧盟 职业教育与培训 教育政策 教育改革 里加周期
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