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关键词： MATLAB  

摘要： Prior to real-time hybrid shaking table testing of the high-speed maglev train-track-bridge system (HSMTTBS), numerical simulations are necessary to optimize experimental design, and enhance the safety, accuracy, and reliability of the experiment. However, simulating such a system under complex conditions poses challenges, particularly in achieving the computational speed required for real-time testing of refined bridge models. In this study, a complex numerical model for real-time testing of the HSMTTBS is presented, using finite element analysis (FEA) software (Ansys) for detailed simulation of bridges, a multibody simulation tool (Simpack) for the high-speed maglev train, and a Matlab-based multidomain simulation tool (Simulink) for shaking tables considering time-delay compensations. A moving load integration method is adopted and further improved for real-time computation of bridge responses. A truncated bridge model is used to simulate only limited spans near the vehicle, rather than the full bridge, to improve computational efficiency. Based on the analysis, the dynamic responses of the vehicle and bridge under complex conditions (e.g., track irregularities and seismic activities) are studied, and the system's safety is assessed. This research provides guidance for real-time hybrid testing of HSMTTBS and offers valuable references for engineering practice. © 2025 Institution of Structural Engineers

关键词： MATLAB  

摘要： The current research combines rotating 3D frame modeling, slip and convective boundary conditions, and a hybrid nanofluid composition (Ag-MoS₂ with paraffin) to address a realistic and complex heat transfer problem. The flow is steady and electrically conductive, driven by the stretching of the surface. The novelty lies in the comparative analysis of Ag and MoS₂ nanofluids, revealing new insights into the superior thermal performance of MoS₂ under certain conditions, as well as the application of advanced algorithmic techniques to solve the problem. This study broadens the scope of nanofluid research by addressing underexplored areas such as microrotation effects and hybrid nanofluids. An algorithmic technique addresses the problem's approximate solutions. The successive over-relaxation method is employed to solve the coupled system of nonlinear equations. The approximate solution is obtained by adapting an algorithm implemented in the MATLAB program. Through graphical and tabular representations in comparison to the primary parameters, the results are physically and quantitatively comprehended. The heat transport rate is significantly enhanced and improved by the nano-composition of Ag-MoS2. The findings show that in both instances of nanofluids, the thickness of the thermal boundary layer will increase as the microrotation parameter increases. An intelligent evaluation of the results reveals that MoS2 has superior heat transfer properties over silver. Molybdenum oxide exhibits better heat transfer characteristics than silver, which highlights the potential of nanofluids to increase heat transfer efficiency and offers important insights into the thermal management of magneto-hydrodynamics systems. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.

关键词： MATLAB  

摘要： This paper explores unmanned aerial vehicle (UAV) tracking control in the presence of actuator faults and external disturbances. An advanced barrier function-based prescribed performance sliding mode control (PPSMC) technique is developed to enhance UAV tracking robustness under these conditions. The approach starts by modeling the UAV dynamics with actuator faults and external disturbances. Tracking errors are then defined relative to the UAV’s actual and desired states, allowing for the design of an appropriate switching surface. A prescribed performance control (PPC) is applied to improve reachability and transient response. The advanced barrier function is utilized to counteract the effects of actuator faults and disturbances, enhancing overall UAV performance. The PPSMC approach is validated using Lyapunov stability theory, demonstrating that tracking errors converge to a small neighborhood around the origin. Simulation results obtained using MATLAB/Simulink and real-time experiments conducted on a Speedgoat machine verify the effectiveness of the proposed PPSMC approach with an advanced barrier function, confirming its suitability for maintaining UAV tracking performance in challenging conditions. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.

关键词： MATLAB  

摘要： The temperature effect on modal parameters such as natural frequencies, mode shapes, and damping ratios is critical for precisely determining the health of a bridge. This is the first study investigating how temperature affects the modal properties of a large continuous rigid-frame bridge. The vibration experiment data was collected and analyzed 39 times within a year's maximum and minimum temperatures. The frequency has been analyzed using the Fast Fourier transform (FFT) algorithm. Mode shape and damping ratio were analyzed using MATLAB software using the covariance-driven stochastic subspace identification method (SSI-COV) and the logarithmic decrement method. Due to the unique shape of the bridge, numerical simulations were performed using Midas Civil software to validate the results. Moreover, the correlation coefficients of frequencies and damping ratios at different temperatures have been evaluated by this observation, which will assist in identifying the large continuous rigid frame bridge's health at various temperatures. © 2025 The Authors

关键词： Wheelchair simulator   Statistical descriptive analysis   Multimodal data   Physiological metrics   System performance   Subjective evaluations  

摘要： WheelSimAnalyser is a MATLAB-based tool designed to process and analyze the WheelSimPhysio-2023 dataset, which includes physiological, questionnaire, and system data from wheelchair simulator studies. The tool streamlines data preprocessing, feature extraction, and visualization, providing researchers with detailed descriptive metrics. By automating key steps, WheelSimAnalyser enables efficient and effective analysis, allowing researchers to derive meaningful insights from complex datasets. The tool supports research on power wheelchair mobility and user experience, enhancing the ability to interpret multimodal data.

关键词： Smart Grid   Integrated modeling and simulation   Co-simulation   Power system control   Communication network   OMNeT plus plus   MATLAB  

摘要： Smart Grid (SG) infrastructure is essential to future society, with communication-based devices playing a pivotal role. Integrated Modeling and Simulation (IMS) of cyber-physical systems (CPS) for power and communication networks is crucial before large-scale implementation. Cosimulation, which involves parallel simulation of power and communication layers, is a powerful approach to IMS, enabling evaluation of controller performance, power system stability, and cyber-attack resilience. This paper presents a state-of-the-art co-simulation of MATLAB and OMNeT++ (CSMO) framework for IMS of SG control and communication systems. Three distinct case studies validate the framework. The first case study assesses communication effects on power generation in a remotely located power plant for automatic generation control. The second case study examines voltage stability through a peer-to-peer communication-based protection system. The third case study evaluates microgrid resilience across five different communication network scenarios. These studies highlight the critical role of IMS in selecting robust communication networks for reliable SG operation. The diverse case studies demonstrate that the CSMO framework effectively optimizes SG control and communication systems for enhanced performance and reliability.

关键词： MATLAB  

摘要： Background: The accurate insertion of brackets is critical to orthodontic treatment success and is a difficult technique facilitated by a variety of direct and indirect procedures, each with its own set of advantages and disadvantages in terms of treatment accuracy and time. This study introduces a novel semiautomatic technique intended to improve bracket placement precision and potentially shorten the treatment time for patients. Results: The conceptualization and design of this mechanism were meticulously executed via SolidWorks, a widely acclaimed computer-aided design software, ensuring that each component of the assembly demonstrated flawless virtual functionality. The exploration then advanced to the formulation of equations, establishing a clear correlation between the mechanical moment and the design’s constants and dimensions. To visualize these theoretical connections, a custom MATLAB program was developed, generating detailed graphs and models. A simulation phase was subsequently undertaken to assess how the crucial parts of the mechanism withstand stress, deformation, and strain in real-world operational scenarios. Conclusions: In the developmental stage, a semiautomated device with exceptional precision that is capable of simultaneously placing multiple orthodontic brackets was employed. A pivotal asset unveiled during this phase was the MATLAB application;it streamlined the generation of meshes and graphs, simplifying the experimentation with various parameter modifications. The simulation results confirmed the mechanism’s ability to manage stress efficiently, which aligns closely with the theoretical predictions. This study underscores the potential for achieving precise and effective orthodontic treatments through the integration of computer-aided design and MATLAB technologies. © The Author(s) 2025.

关键词： Bio-convection   Three-dimensional flow   Gyrotactic microorganisms   Sisko nanofluid   Nonlinear radiation   Activation energy   MATLAB  

摘要： Nanotechnology is fascinating pronounced deliberation because of its vast uses in nano-robot, aircraft industry, bio-nano-metric devices, water desalination, medicine, cancer treatment, nano-tubes metric, rubber metal and nano-metric pregnant. Several investigators are involved in exploring the belongings of the magnetic field owing to its wide utilizations in turbo machinery, metallurgy, polymer industry, blood flow, connection of nuclear accelerators and electrical furnace, nuclear reactor, etc. Furthermore, the aspect of bioconvection has been thoroughly explored because of its wide range of uses in bio-microsystems, oil modeling, gas-bearing deposit sink and microbial enhanced oil reclamation. The prime intention of existing investigation is to study the threedimensional double stratification flow of Sisko nanofluid containing microorganisms over a stretching sheet. The properties of nonlinear radiation along with the magnetic field are take into consideration in this mathematical analysis. Additionally, the aspects of activation energy, chemical reaction and mixed convection are also endorsed. An appropriate set of similarity transformations is deliberated to change the PDEs into a set of combined nonlinear ODEs. We achieved numerical solution of the nonlinear ODEs because of the (bvp4c) MATLAB built-in command. The impacts of numerous developing substantial parameters of Sisko nanofluid beside the profile's concentration, temperature, microorganisms, Sherwood number, Nusselt number have been deliberated also studied along tables and graphs. It is investigated that the temperature profile declines by an intensification in the estimates of stretching parameter, material parameter appropriate to Sisko fluid and the Prandtl number, while its value growths with the thermophoresis and magnetic parameter. Correspondingly, we perceived that the thermophoresis and Brownian motion parameters have the opposite impacts against Sisko nanofluid concentration. It should be n

关键词： 肠道病毒A组71型   泛素特异性蛋白酶21   2A蛋白酶   RLR信号通路  

摘要： 目的 探究泛素特异性蛋白酶21 (ubiquitin-specific protease 21, USP21)在肠道病毒A组71型(enterovirus group A type 71, EV-A71)感染中的作用。 方法 采集EV-A71感染患儿与健康儿童各24例外周全血，分离出外周血单个核细胞(peripheral blood mononuclear cell, PBMC)，实时荧光定量PCR(real-time fluorescence quantitative PCR，qPCR)检测PBMC中USP21 mRNA表达水平。采用qPCR或蛋白印迹试验(western blot, WB)观察过表达USP21或敲除USP21后对EV-A71复制的影响；WB检测EV-A71结构蛋白VP1、RIG-I样受体(RIG-I-like receptor, RLR)信号通路关键分子蛋白水平及干扰素调节因子3 (interferon regulatory factor 3, IRF3)磷酸化。免疫共沉淀(co-immunoprecipitation，Co-IP)分析USP21对EV-A71非结构蛋白2A蛋白酶(2A pro )泛素水平的影响。 结果 与健康儿童相比，EV-A71感染患儿PBMC中USP21 mRNA表达明显升高。过表达USP21后显著提升EV-A71所致的细胞病变效应，上调VP1 mRNA和蛋白水平并促进EV-A71复制，细胞活性也随USP21的转染水平增高而明显下降；而敲除USP21基因后发现EV-A71 VP1 mRNA水平较对照组显著下调。另外，过表达USP21并不影响EV-A71 2A pro 的转录水平，但可以上调2A pro 的蛋白表达，同时降低2A pro 的泛素化水平，抑制线粒体抗病毒信号蛋白(mitochondria antiviral signaling protein, MAVS)、黑色素瘤分化相关基因5 (melanoma differentiation-associated gene 5, MDA5)的蛋白表达以及IRF3的磷酸化水平，下调干扰素-β (interferon-β，IFN-β)mRNA水平。敲除USP21可挽救EV-A71感染导致的MAVS和MDA5蛋白水平下调，促进IRF3的磷酸化并上调IFN-β mRNA水平。 结论 USP21可通过降低2A pro 的泛素化水平，降低MAVS和MDA5蛋白表达，负向调控干扰素信号通路而促进EV-A71复制。

关键词： Porous media   Capillary pressure   Pore morphology method   Packed bed   Fluid saturation modeling   Capillary bridge  

摘要： An alternative to the popular volume-of-fluid (VOF) and lattice Boltzmann (LB) methods for simulating fluid flow in porous media is the purely geometric pore morphology method (PMM). The PMM does not require solving partial differential equations and is therefore, orders of magnitude faster than the VOF and LB methods in terms of CPU time (e.g., about a week on 100 cores for the VOF vs. about 30 mins on one core for the PMM in our case). The PMM employs voxel-based morphological operations to provide a quasi-static approximation for capillary flow in porous structures. This paper presents step-by-step instructions for how to implement the PMM in the MATLAB environment, and further to benchmark the method using the simulation results obtained from the VOF and other continuum-based numerical methods. More specifically, this paper presents PMM simulations for the intrusion of a non-wetting fluid in two- and three-dimensional porous media with heterogeneous contact angles. Detailed discussions are also presented for the pros and cons of the PMM and how its non-continuum nature can be used as an advantage to conduct two-phase flow simulations in geometries where a symmetry boundary condition cannot be applied.