Journal of Computational and Applied Mathematics最新文献

{"title":"Classical and objective Bayesian inference of Cpy for first-failure progressively censored samples","authors":"Sanku Dey ,&nbsp;Subhankar Dutta ,&nbsp;Devendra Kumar","doi":"10.1016/j.cam.2025.116841","DOIUrl":"10.1016/j.cam.2025.116841","url":null,"abstract":"<div><div>This article takes into account the estimation of the process capability index (PCI), <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi><mi>y</mi></mrow></msub></math></span> using first failure progressive censoring scheme (FFPCS). On the basis of FFPCS, <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi><mi>y</mi></mrow></msub></math></span> is estimated for the inverse Nakagami distribution using maximum likelihood (ML), maximum product spacing (MPS) and Bayesian estimation methods. Bayes estimator of <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi><mi>y</mi></mrow></msub></math></span> is obtained under squared error and linear exponential loss functions using objective prior. Besides, approximate confidence intervals (CIs) for the index <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi><mi>y</mi></mrow></msub></math></span> using both classical methods are obtained and compared with the highest posterior density (HPD) credible intervals. Finally, a simulated study is performed to assess the finite sample performance of the proposed point estimates of <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>p</mi><mi>y</mi></mrow></msub></math></span> based on mean squared errors (MSEs) and interval estimates are compared with their average length and coverage probabilities. In order to demonstrate the usefulness of the proposed index and estimation techniques, one real data set from the agricultural machine elevators is reanalyzed.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116841"},"PeriodicalIF":2.1,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144480619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid radial kernels for solving weakly singular Fredholm integral equations: Balancing accuracy and stability in meshless methods","authors":"Davoud Moazami,&nbsp;Mohsen Esmaeilbeigi,&nbsp;Tahereh Akbari","doi":"10.1016/j.cam.2025.116848","DOIUrl":"10.1016/j.cam.2025.116848","url":null,"abstract":"<div><div>Over the past few decades, kernel-based approximation methods had achieved astonishing success in solving different problems in the field of science and engineering. However, when employing the direct or standard method of performing computations using infinitely smooth kernels, a conflict arises between the accuracy that can be theoretically attained and the numerical stability. In other words, when the shape parameter tends to zero, the operational matrix for the standard bases with infinitely smooth kernels become severely ill-conditioned. This conflict can be managed applying hybrid kernels. The hybrid kernels extend the approximation space and provide high flexibility to strike the best possible balance between accuracy and stability. In the current study, an innovative approach using hybrid radial kernels (HRKs) is provided to solve weakly singular Fredholm integral equations (WSFIEs) of the second kind in a meshless scheme. The approach employs hybrid kernels built on dispersed nodes as a basis within the discrete collocation technique. This method transforms the problem being studied into a linear system of algebraic equations. Also, the particle swarm optimization (PSO) algorithm is utilized to calculate the optimal parameters for the hybrid kernels, which is based on minimizing the maximum absolute error (MAE). We also study the error estimate of the suggested scheme. Lastly, we assess the accuracy and validity of the hybrid technique by carrying out various numerical experiments. The numerical findings show that the estimates obtained from hybrid kernels are significantly more accurate in solving WSFIEs compared to pure kernels. Additionally, it was revealed that the hybrid bases remain stable across various values of the shape parameters.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116848"},"PeriodicalIF":2.1,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multicontinuum modeling of time-fractional diffusion-wave equation in heterogeneous media","authors":"Huiran Bai ,&nbsp;Dmitry Ammosov ,&nbsp;Yin Yang ,&nbsp;Wei Xie ,&nbsp;Mohammed Al Kobaisi","doi":"10.1016/j.cam.2025.116846","DOIUrl":"10.1016/j.cam.2025.116846","url":null,"abstract":"<div><div>This paper considers a time-fractional diffusion-wave equation with a high-contrast heterogeneous coefficient. A numerical solution to this problem can present great computational challenges due to its multiscale nature. Therefore, in this paper, we derive a multicontinuum time-fractional diffusion-wave model using the multicontinuum homogenization method. For this purpose, we formulate constraint cell problems considering various homogenized effects. These cell problems are implemented in oversampled regions to avoid boundary effects. By solving the cell problems, we obtain multicontinuum expansions of fine-scale solutions. Then, using these multicontinuum expansions and supposing the smoothness of the macroscopic variables, we rigorously derive the corresponding multicontinuum model. Finally, we present numerical results for two-dimensional model problems with different time-fractional derivatives to verify the accuracy of our proposed approach.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116846"},"PeriodicalIF":2.1,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel option pricing framework using Pell-Locas collocation method under the stochastic local volatility model","authors":"Fares Alazemi","doi":"10.1016/j.cam.2025.116840","DOIUrl":"10.1016/j.cam.2025.116840","url":null,"abstract":"<div><div>In this paper, we obtain the European option price using the Pell-Lucas collocation numerical method. To do this, we present the long-memory version of the hybrid stochastic local volatility model to forecast asset prices based on futures market data. Next, we apply financial market concepts such as the self-financing portfolio and the no-arbitrage theorem to derive a partial differential equation (PDE) for evaluating the option price. The structure of the PDE is complex, so to solve it, we employ a spectral collocation method based on Pell-Lucas polynomials as basis functions. Since the coefficients of the governing PDE are variable, the collocation method offers several advantages over the Galerkin and Tau methods. To implement this approach, we compute the operational matrix of Pell-Lucas polynomials and approximate the first, second, and mixed partial derivatives of the model. By collocating the equation, we obtain a system of algebraic equations that can be solved using traditional numerical methods.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116840"},"PeriodicalIF":2.1,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning to manage retrial queueing system M/G/1/N under F-policy with discouraged customers and fuzzy costs and its implementation in medical centers","authors":"Sudeep Singh Sanga,&nbsp;Nidhi","doi":"10.1016/j.cam.2025.116843","DOIUrl":"10.1016/j.cam.2025.116843","url":null,"abstract":"<div><div>This study aims to investigate an M/G/1/N retrial queueing model under <em>F</em>-policy, considering discouragement behaviors of customers such as balking and reneging. The noble feature of the model is to control the arrival of customers in the system through the implementation of <em>F</em>-policy. In this model, when a customer arrives and finds the server busy, they are compelled to join a retrial orbit and retry for service after a certain period. In the presence of long queues, customers may become discouraged and choose not to join the system or leave without being served. The queue size distribution for the system is obtained by using the steady-state Chapman–Kolmogorov (C–K) equations with a supplementary variable for the remaining service time. These equations are then solved using the Laplace-Stieltjes transform (LST) and the recursive technique. Various performance measures are established based on the queue size distribution to explore the system’s behavior. Moreover, this study explores the application of machine learning (ML) techniques in predicting the waiting time of customers in the system and the reneging rate of customers with respect to system size in diverse industries relying on queueing systems such as railway ticket counters, hospitals, and banks. We also formulate a fuzzy cost function where the cost components are represented as trapezoidal fuzzy numbers. The signed distance method is utilized to defuzzify the cost function, converting it into a crisp value for practical implementation. In order to achieve the minimum cost of the system corresponding to the optimal values for decision variables, two optimization techniques, namely the sine cosine algorithm (SCA) and particle swarm optimization (PSO), are implemented. The practical application of the developed model is demonstrated in a health checkup center (HCC), showcasing its real-world utility in operational settings.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116843"},"PeriodicalIF":2.1,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toroidal density-equalizing map for genus-one surfaces","authors":"Shunyu Yao,&nbsp;Gary P.T. Choi","doi":"10.1016/j.cam.2025.116844","DOIUrl":"10.1016/j.cam.2025.116844","url":null,"abstract":"<div><div>Density-equalizing map is a shape deformation technique originally developed for cartogram creation and sociological data visualization on planar geographical maps. In recent years, there has been an increasing interest in developing density-equalizing mapping methods for surface and volumetric domains and applying them to various problems in geometry processing and imaging science. However, the existing surface density-equalizing mapping methods are only applicable to surfaces with relatively simple topologies but not surfaces with topological holes. In this work, we develop a novel algorithm for computing density-equalizing maps for toroidal surfaces. In particular, different shape deformation effects can be easily achieved by prescribing different population functions on the torus and performing diffusion-based deformations on a planar domain with periodic boundary conditions. Furthermore, the proposed toroidal density-equalizing mapping method naturally leads to an effective method for computing toroidal parameterizations of genus-one surfaces with controllable area changes, with the toroidal area-preserving parameterization being a prime example. Experimental results are presented to demonstrate the effectiveness of our proposed methods.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"472 ","pages":"Article 116844"},"PeriodicalIF":2.1,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144313235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Cs-smooth mixed degree and regularity isogeometric spline space over planar multi-patch domains","authors":"Mario Kapl ,&nbsp;Aljaž Kosmač ,&nbsp;Vito Vitrih","doi":"10.1016/j.cam.2025.116836","DOIUrl":"10.1016/j.cam.2025.116836","url":null,"abstract":"<div><div>We construct over a given bilinear multi-patch domain a novel <span><math><msup><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msup></math></span>-smooth mixed degree and regularity isogeometric spline space, which possesses the degree <span><math><mrow><mi>p</mi><mo>=</mo><mn>2</mn><mi>s</mi><mo>+</mo><mn>1</mn></mrow></math></span> and regularity <span><math><mrow><mi>r</mi><mo>=</mo><mi>s</mi></mrow></math></span> in a small neighborhood around the edges and vertices, and the degree <span><math><mrow><mover><mrow><mi>p</mi></mrow><mrow><mo>˜</mo></mrow></mover><mo>≤</mo><mi>p</mi></mrow></math></span> with regularity <span><math><mrow><mover><mrow><mi>r</mi></mrow><mrow><mo>˜</mo></mrow></mover><mo>=</mo><mover><mrow><mi>p</mi></mrow><mrow><mo>˜</mo></mrow></mover><mo>−</mo><mn>1</mn><mo>≥</mo><mi>r</mi></mrow></math></span> in all other parts of the domain. Our proposed approach relies on the technique Kapl and Vitrih (2021), which requires for the <span><math><msup><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msup></math></span>-smooth isogeometric spline space a degree at least <span><math><mrow><mi>p</mi><mo>=</mo><mn>2</mn><mi>s</mi><mo>+</mo><mn>1</mn></mrow></math></span> on the entire multi-patch domain. Similar to Kapl and Vitrih (2021), the <span><math><msup><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msup></math></span>-smooth mixed degree and regularity spline space is generated as the span of basis functions that correspond to the individual patches, edges and vertices of the domain. The reduction of degrees of freedom for the functions in the interior of the patches is achieved by introducing an appropriate mixed degree and regularity underlying spline space over <span><math><msup><mrow><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> to define the functions on the single patches. We further extend our construction with a few examples to the class of bilinear-like <span><math><msup><mrow><mi>G</mi></mrow><mrow><mi>s</mi></mrow></msup></math></span> multi-patch parameterizations (Kapl and Vitrih (2018); Kapl and Vitrih (2021)), which enables the design of multi-patch domains having curved boundaries and interfaces. Finally, the great potential of the <span><math><msup><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msup></math></span>-smooth mixed degree and regularity isogeometric spline space for performing isogeometric analysis is demonstrated by several numerical examples of solving two particular high order partial differential equations, namely the biharmonic and triharmonic equation, via the isogeometric Galerkin method.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116836"},"PeriodicalIF":2.1,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel softmax method for solving second Benney-Luke equation","authors":"Nguyen Minh Tuan ,&nbsp;Phayung Meesad","doi":"10.1016/j.cam.2025.116791","DOIUrl":"10.1016/j.cam.2025.116791","url":null,"abstract":"<div><div>This paper firstly introduces a novel approach utilizing the softmax method to solve the second Benney-Luke equation, specifically for the case where the parameter is equal to 2. Traditionally used in machine learning for classification tasks, the softmax function is applied here to derive exact solutions for this nonlinear partial differential equation. The method produces a variety of solution forms, including hyperbolic, trigonometric, and one-soliton solutions. These results offer valuable insights into the equation’s structure, expanding the understanding of wave phenomena on surface areas in mathematical physics, and contributing to the development of more comprehensive solution techniques for nonlinear wave equations.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"472 ","pages":"Article 116791"},"PeriodicalIF":2.1,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144313178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The large time step scheme of Euler equations with source terms for nozzle flows","authors":"Han Ding ,&nbsp;Zhansen Qian ,&nbsp;Haitao Dong ,&nbsp;Chong Pan","doi":"10.1016/j.cam.2025.116867","DOIUrl":"10.1016/j.cam.2025.116867","url":null,"abstract":"<div><div>Hyperbolic conservation laws with source terms govern critical flow phenomena, including turbulence transport and hypersonic chemically reacting flows. Despite their engineering significance, traditional numerical schemes for these systems face strict CFL (≤1.0) constraints, limiting computational efficiency. This study addresses the computational challenges posed by geometric source terms in Euler equations governing compressible nozzle flows. The proposed approach decomposes the governing equations into convective and source components: while convection is resolved via an LTS Godunov scheme, geometric source terms—arising from nozzle area variations (quasi-1D) or cylindrical coordinate transformations (2D axisymmetric)—are discretized using a novel combination of explicit and exact schemes. Numerical validations include: (1) quasi-1D cases under supersonic start/non-start conditions (internal shocks near outlets) at CFL ≤8.0, demonstrating shock-capturing accuracy with 55 % RMS error reduction at CFL = 8.0; (2) 2D hypersonic nozzle flows (Mach 4.0 design), achieving stable simulations at CFL = 5.0 with &lt;1 % exit Mach deviation and 66 % runtime reduction. Results confirm that the proposed LTS framework overcomes CFL ≤1.0 limitations while enhancing efficiency—computational costs and errors decrease monotonically with increasing CFL numbers. This method establishes a generalizable paradigm for stiff, multidimensional Euler systems, balancing robustness and accuracy without sacrificing explicit computation advantages.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116867"},"PeriodicalIF":2.1,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144330219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Divergence-free stabilized virtual element method for the unsteady incompressible Navier–Stokes problem","authors":"Yang Li ,&nbsp;Minfu Feng ,&nbsp;Yanhong Bai","doi":"10.1016/j.cam.2025.116838","DOIUrl":"10.1016/j.cam.2025.116838","url":null,"abstract":"<div><div>In this paper, we extend the divergence-free virtual element method to the unsteady incompressible Navier–Stokes problem, and by enhancing the stabilizing term of the virtual element method, the method can not only exactly preserve the divergence-free constraint, but also control spurious oscillations in the velocity due to dominant convection. Both the continuous-in-time and the fully discrete schemes (Euler semi-implicit scheme) are proposed. The corresponding stability and error estimates are analyzed. Importantly, error estimates are derived in which the constants are independent of the Reynolds number, and error estimates do not explicitly depend on the pressure. Several numerical experiments verify the theoretical results and the favorable performance of the method.</div></div>","PeriodicalId":50226,"journal":{"name":"Journal of Computational and Applied Mathematics","volume":"473 ","pages":"Article 116838"},"PeriodicalIF":2.1,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}