Mathematical and Computational Applications最新文献_第3页

Simulation of Temperature Field in Steel Billets during Reheating in Pusher-Type Furnace by Meshless Method 用无网格法模拟推杆式加热炉再加热过程中钢坯的温度场

Mathematical and Computational Applications Pub Date : 2024-04-24 DOI: 10.3390/mca29030030

Qingguo Liu, U. Hanoglu, Z. Rek, B. Šarler

{"title":"Simulation of Temperature Field in Steel Billets during Reheating in Pusher-Type Furnace by Meshless Method","authors":"Qingguo Liu, U. Hanoglu, Z. Rek, B. Šarler","doi":"10.3390/mca29030030","DOIUrl":"https://doi.org/10.3390/mca29030030","url":null,"abstract":"Using a meshless method, a simulation of steel billets in a pusher-type reheating furnace is carried out for the first time. The simulation represents an affordable way to replace the measurements. The heat transfer from the billets with convection and radiation is considered. Inside each of the billets, the heat diffusion equation is solved on a two-dimensional central slice of the billet. The diffusion equation is solved in a strong form by the Local Radial Basis Function Collocation Method (LRBFCM) with explicit time-stepping. The ray tracing procedure solves the radiation, where the view factors are computed with the Monte Carlo method. The changing number of billets in the furnace at the start and the end of the loading and unloading of the furnace is considered. A sensitivity study on billets' temperature evolution is performed as a function of a different number of rays used in the Monte Carlo method, different stopping times of the billets in the furnace, and different spacing between the billets. The temperature field simulation is also essential for automatically optimizing the furnace’s productivity, energy consumption, and the billet’s quality. For the first time, the LRBFCM is successfully demonstrated for solving such a complex industrial problem.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"8 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140663672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Robust FOPD Controller That Allows Faster Detection of Defects for Touch Panels 稳健的 FOPD 控制器可更快地检测触摸屏缺陷

Mathematical and Computational Applications Pub Date : 2024-04-16 DOI: 10.3390/mca29020029

Yuan-Jay Wang

{"title":"A Robust FOPD Controller That Allows Faster Detection of Defects for Touch Panels","authors":"Yuan-Jay Wang","doi":"10.3390/mca29020029","DOIUrl":"https://doi.org/10.3390/mca29020029","url":null,"abstract":"This study aims to synthesize and implement a robust fractional order PD (RFOPD) controller to increase the speed at which defects in automated touch panel inspection systems (ATPISs) are detected. A three-dimensional orthogonal stage (TDOS) driven by BLDC servo motors moves the inspection pen (IP) vertically and horizontally. The dynamic equation relating the BLDC servo motor input to the tip motion is established. A touch position identification (TPI) system is used to locate the touch point rapidly. An RFOPD controller is used to actuate the BLDC servo motors and move the TDOS rapidly and accurately in three dimensions. This method displaces the IP to any specified position and shows user-defined inspection trajectories on the touch screens. The gain-phase margin tester (GPMT) and stability equation methods are exploited to schedule the RFOPD controller gain settings and to maintain the specific safety margins for the controlled system. The simulation studies show that the proposed RFOPD controller exhibits better tracking and disturbance rejection responses than a conventional PID controller. The robustness of the RFOPD-controlled ATPIS, considering unmodeled uncertainties and friction-induced disturbances, is verified through simulation and experimental studies. Several user-defined inspection patterns are used to verify performance, and the experimental results show that the proposed RFOPD controller is effective.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"37 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140694951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Global Behavior of Solutions to a Higher-Dimensional System of Difference Equations with Lucas Numbers Coefficients 含卢卡斯数系数的高维差分方程组解的全局行为

Mathematical and Computational Applications Pub Date : 2024-03-31 DOI: 10.3390/mca29020028

Messaoud Berkal, J. F. Navarro, R. Abo-zeid

引用次数: 0

Modeling of Chemical Vapor Infiltration for Fiber-Reinforced Silicon Carbide Composites Using Meshless Method of Fundamental Solutions 使用无网格基本解法建立碳化硅纤维增强复合材料的化学蒸汽渗透模型

Mathematical and Computational Applications Pub Date : 2024-03-22 DOI: 10.3390/mca29020027

Patrick Mahoney, A. Povitsky

引用次数: 0

A Coupled Finite-Boundary Element Method for Efficient Dynamic Structure-Soil-Structure Interaction Modeling 用于高效动态结构-土-结构相互作用建模的耦合有限元-边界元方法

Mathematical and Computational Applications Pub Date : 2024-03-18 DOI: 10.3390/mca29020024

Parham Azhir, Jafar Asgari Marnani, M. Panji, M. S. Rohanimanesh

引用次数: 0

M5GP: Parallel Multidimensional Genetic Programming with Multidimensional Populations for Symbolic Regression M5GP：用于符号回归的多维种群并行多维遗传编程

Mathematical and Computational Applications Pub Date : 2024-03-18 DOI: 10.3390/mca29020025

Luis Cárdenas Florido, Leonardo Trujillo, Daniel E. Hernandez, Jose Manuel Muñoz Contreras

{"title":"M5GP: Parallel Multidimensional Genetic Programming with Multidimensional Populations for Symbolic Regression","authors":"Luis Cárdenas Florido, Leonardo Trujillo, Daniel E. Hernandez, Jose Manuel Muñoz Contreras","doi":"10.3390/mca29020025","DOIUrl":"https://doi.org/10.3390/mca29020025","url":null,"abstract":"Machine learning and artificial intelligence are growing in popularity thanks to their ability to produce models that exhibit unprecedented performance in domains that include computer vision, natural language processing and code generation. However, such models tend to be very large and complex and impossible to understand using traditional analysis or human scrutiny. Conversely, Symbolic Regression methods attempt to produce models that are relatively small and (potentially) human-readable. In this domain, Genetic Programming (GP) has proven to be a powerful search strategy that achieves state-of-the-art performance. This paper presents a new GP-based feature transformation method called M5GP, which is hybridized with multiple linear regression to produce linear models, implemented to exploit parallel processing on graphical processing units for efficient computation. M5GP is the most recent variant from a family of feature transformation methods (M2GP, M3GP and M4GP) that have proven to be powerful tools for both classification and regression tasks applied to tabular data. The proposed method was evaluated on SRBench v2.0, the current standard benchmarking suite for Symbolic Regression. Results show that M5GP achieves performance that is competitive with the state-of-the-art, achieving a top-three rank on the most difficult subset of black-box problems. Moreover, it achieves the lowest computation time when compared to other GP-based methods that have similar accuracy scores.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"25 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140231904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of Local Radial Basis Function Collocation Method for Diffusion Problems Structured with Multiquadrics and Polyharmonic Splines 评估用多四边形和多谐样条线构造扩散问题的局部径向基函数配准法

Mathematical and Computational Applications Pub Date : 2024-03-17 DOI: 10.3390/mca29020023

Izaz Ali, U. Hanoglu, R. Vertnik, B. Šarler

{"title":"Assessment of Local Radial Basis Function Collocation Method for Diffusion Problems Structured with Multiquadrics and Polyharmonic Splines","authors":"Izaz Ali, U. Hanoglu, R. Vertnik, B. Šarler","doi":"10.3390/mca29020023","DOIUrl":"https://doi.org/10.3390/mca29020023","url":null,"abstract":"This paper aims to systematically assess the local radial basis function collocation method, structured with multiquadrics (MQs) and polyharmonic splines (PHSs), for solving steady and transient diffusion problems. The boundary value test involves a rectangle with Dirichlet, Neuman, and Robin boundary conditions, and the initial value test is associated with the Dirichlet jump problem on a square. The spectra of the free parameters of the method, i.e., node density, timestep, shape parameter, etc., are analyzed in terms of the average error. It is found that the use of MQs is less stable compared to PHSs for irregular node arrangements. For MQs, the most suitable shape parameter is determined for multiple cases. The relationship of the shape parameter with the total number of nodes, average error, node scattering factor, and the number of nodes in the local subdomain is also provided. For regular node arrangements, MQs produce slightly more accurate results, while for irregular node arrangements, PHSs provide higher accuracy than MQs. PHSs are recommended for use in diffusion problems that require irregular node spacing.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"58 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Variability on Functionally Graded Plates’ Deflection Due to Uncertainty on Carbon Nanotubes’ Properties 碳纳米管特性的不确定性导致的功能分级板挠度变化

Mathematical and Computational Applications Pub Date : 2024-03-16 DOI: 10.3390/mca29020022

Alda Carvalho, Ana Martins, Ana F. Mota, M.A.R. Loja

{"title":"Variability on Functionally Graded Plates’ Deflection Due to Uncertainty on Carbon Nanotubes’ Properties","authors":"Alda Carvalho, Ana Martins, Ana F. Mota, M.A.R. Loja","doi":"10.3390/mca29020022","DOIUrl":"https://doi.org/10.3390/mca29020022","url":null,"abstract":"Carbon nanotubes are widely used as material reinforcement in diverse fields of engineering. Being that their contribution is significant to improving the mean properties of the resulting materials, it is important to assess the influence of the variability on carbon nanotubes’ material and geometrical properties to structures’ responses. This work considers functionally graded plates constituted by an aluminum continuous phase reinforced with single-walled or multi-walled carbon. The nanotubes' weight fraction evolution through the thickness is responsible for the plates’ functional gradient. The plates’ samples are simulated considering that only the nanotubes’ material and geometrical characteristics are affected by uncertainty. The results obtained from the multiple regression models developed allow us to conclude that the length of the nanotubes has no impact on the maximum transverse displacement of the plates in opposition to the carbon nanotubes’ weight fraction evolution, their internal and external diameters, and the Young’s modulus. The multiple regression models developed can be used as alternative prediction tools within the domain of the study.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"79 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140236285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Semi-Supervised Machine Learning Method for Predicting Observed Individual Risk Preference Using Gallup Data 利用盖洛普数据预测观察到的个人风险偏好的半监督机器学习方法

Mathematical and Computational Applications Pub Date : 2024-03-15 DOI: 10.3390/mca29020021

Faroque Ahmed, Mrittika Shamsuddin, Tanzila Sultana, R. Shamsuddin

{"title":"Semi-Supervised Machine Learning Method for Predicting Observed Individual Risk Preference Using Gallup Data","authors":"Faroque Ahmed, Mrittika Shamsuddin, Tanzila Sultana, R. Shamsuddin","doi":"10.3390/mca29020021","DOIUrl":"https://doi.org/10.3390/mca29020021","url":null,"abstract":"Risk and uncertainty play a vital role in almost every significant economic decision, and an individual’s propensity to make riskier decisions also depends on various circumstances. This article aims to investigate the effects of social and economic covariates on an individual’s willingness to take general risks and extends the scope of existing works by using quantitative measures of risk-taking from the GPS and Gallup datasets (in addition to the qualitative measures used in the literature). Based on the available observed risk-taking data for one year, this article proposes a semi-supervised machine learning-based approach that can efficiently predict the observed risk index for those countries/individuals for years when the observed risk-taking index was not collected. We find that linear models are insufficient to capture certain patterns among risk-taking factors, and non-linear models, such as random forest regression, can obtain better root mean squared values than those reported in past literature. In addition to finding factors that agree with past studies, we also find that subjective well-being influences risk-taking behavior.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"6 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140241218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Four-Variable Shear Deformation Theory for the Static Analysis of FG Sandwich Plates with Different Porosity Models 用于不同孔隙率模型 FG 夹层板静态分析的四变量剪切变形理论

Mathematical and Computational Applications Pub Date : 2024-03-08 DOI: 10.3390/mca29020020

R. A. Alghanmi, Rawan H. Aljaghthami

{"title":"A Four-Variable Shear Deformation Theory for the Static Analysis of FG Sandwich Plates with Different Porosity Models","authors":"R. A. Alghanmi, Rawan H. Aljaghthami","doi":"10.3390/mca29020020","DOIUrl":"https://doi.org/10.3390/mca29020020","url":null,"abstract":"This study is centered on examining the static bending behavior of sandwich plates featuring functionally graded materials, specifically addressing distinct representations of porosity distribution across their thickness. The composition of the sandwich plate involves a ceramic core and two face sheets with functionally graded properties. Mechanical loads with a sinusoidal distribution are applied to the sandwich plate, and a four-variable shear deformation theory is employed to establish the displacement field. Notably, this theory involves only four unknowns, distinguishing it from alternative shear deformation theories. Equilibrium equations are derived using the virtual work concept, and Navier’s method is applied to obtain the solution. The study addresses the impact of varying porosities, inhomogeneity parameters, aspect ratios, and side-to-thickness ratios on the static bending behavior of the sandwich plates. The influence of various porosities, inhomogeneity parameter, aspect ratio, and side-to-thickness ratio of the sandwich plates are explored and compared in the context of static bending behavior. The three porosity distributions are compared in terms of their influence on the bending behavior of the sandwich plate. The findings indicate that a higher porosity causes larger deflections and Model A has the highest central deflection. Adopting the four-variable shear deformation theory demonstrated its validity since the results were similar to those obtained in the literature. Several important findings have been found, which could be useful in the construction and application of FG sandwich structures. Examples of comparison will be discussed to support the existing theory’s accuracy. Further findings are presented to serve as benchmarks for comparison.","PeriodicalId":352525,"journal":{"name":"Mathematical and Computational Applications","volume":"69 S26","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140257263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1