Journal of Computational Science最新文献

Discrete fractional neural networks within the framework of octonions: A preliminary exploration

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-04-05 DOI: 10.1016/j.jocs.2025.102586

Jie Ran , Yonghui Zhou , Thabet Abdeljawad , Hao Pu

{"title":"Discrete fractional neural networks within the framework of octonions: A preliminary exploration","authors":"Jie Ran , Yonghui Zhou , Thabet Abdeljawad , Hao Pu","doi":"10.1016/j.jocs.2025.102586","DOIUrl":"10.1016/j.jocs.2025.102586","url":null,"abstract":"<div><div>Conventional neural networks constructed on real or complex domains have limitations in capturing multi-dimensional data with memory effects. This work is a preliminary exploration of discrete fractional neural network modeling within the framework of octonions. Initially, by introducing the discrete fractional Caputo difference operator into the octonion domain, we establish a novel system of discrete fractional delayed octonion-valued neural networks (DFDOVNNs). The new system provides a theoretical support for developing neural network algorithms that are useful for solving complex, multi-dimensional problems with memory effects in the real world. We then use the Cayley–Dickson technique to divide the system into four discrete fractional complex-valued neural networks to deal with the non-commutative and non-associative properties of the hyper-complex domain. Next, we establish the existence and uniqueness of the equilibrium point to the system based on the homeomorphism theory. Furthermore, by employing the Lyapunov theory, we establish some straightforward and verifiable linear matrix inequality (LMI) criteria to ensure global Mittag-Leffler stability of the system. In addition, an effective feedback controller is developed to achieve the system’s drive-response synchronization in the Mittag-Leffler sense. Finally, two numerical examples support the theoretical analysis. This research introduces a novel direction in neural network studies that promises to significantly advance the fields of signal processing, control systems, and artificial intelligence.</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102586"},"PeriodicalIF":3.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of inlet velocity waveform shape on hemodynamics

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-27 DOI: 10.1016/j.jocs.2025.102579

Justen R. Geddes, Timothy D. King, Cyrus Tanade, William Ladd, Nusrat Sadia Khan, Amanda Randles

{"title":"Impact of inlet velocity waveform shape on hemodynamics","authors":"Justen R. Geddes, Timothy D. King, Cyrus Tanade, William Ladd, Nusrat Sadia Khan, Amanda Randles","doi":"10.1016/j.jocs.2025.102579","DOIUrl":"10.1016/j.jocs.2025.102579","url":null,"abstract":"<div><div>Monitoring disease development in arteries, which supply oxygen and nutrients to the body, is crucial and can be assessed using hemodynamic metrics. Hemodynamic metrics can be calculated via computational fluid dynamic simulation of patient-specific geometries. These simulations are known to be heavily influenced by boundary conditions, such as time-dependent inlet flow. However, the effects of inlet flow profiles have not previously been quantified or understood. Here we quantify the effects of modulating temporal arterial waveforms on hemodynamic metrics. Building on our previous work that identified the minimum number of points of interest needed to characterize a left coronary artery inlet waveform, here, we extend this approach to pulmonary and carotid artery waveforms, pinpointing critical points of interest on these waveforms. Using a systematic variation of these points, we quantify the effects on hemodynamic metrics such as wall shear stress, oscillatory shear index, and relative residence time. We simulate using 1D Navier–Stokes and 3D lattice Boltzmann simulation approaches conducted on high performance compute clusters. The results pinpoint parts of the waveform that are most susceptible to perturbations and measurement error. The impacts of this work include the construction of a method that can be applied to other fluid simulations with pulsatile inlet conditions and the ability to distinguish the vital parts of a pulsatile inlet condition for computational fluid dynamic simulations and clinical metrics. This work is an extension of work published at the International Conference on Computational Science (ICCS-2024), (Geddes et al., 2024).</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102579"},"PeriodicalIF":3.1,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bearing-distance flocking with zone-based interactions in constrained dynamic environments

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-23 DOI: 10.1016/j.jocs.2025.102574

Hossein B. Jond

{"title":"Bearing-distance flocking with zone-based interactions in constrained dynamic environments","authors":"Hossein B. Jond","doi":"10.1016/j.jocs.2025.102574","DOIUrl":"10.1016/j.jocs.2025.102574","url":null,"abstract":"<div><div>This paper presents a novel zone-based flocking control approach suitable for dynamic multi-agent systems (MAS). Inspired by Reynolds behavioral rules for <em>boids</em>, flocking behavioral rules with the zones of repulsion, conflict, attraction, and surveillance are introduced. For each agent, using only bearing and distance measurements, behavioral contribution vectors quantify the local separation, local and global flock velocity alignment, local cohesion, obstacle avoidance and boundary conditions, and strategic separation for avoiding alien agents. The control strategy uses the local perception-based behavioral contribution vectors to guide each agent’s motion. Additionally, the control strategy incorporates a directionally aware obstacle avoidance mechanism that prioritizes obstacles in the agent’s forward path. Simulation results validate the effectiveness of the model in creating flexible, adaptable, and scalable flocking behavior. Asymptotic stability and convergence to a stable flocking configuration for any initial conditions provided the interaction graph is a spanning tree are demonstrated. The flocking model’s reliance on locally sensed bearing and distance measurements ensures scalability and robustness, particularly in scenarios where communication is unreliable or resource-intensive. This makes it well-suited for real-world applications demanding seamless operation in highly dynamic and distributed environments.</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102574"},"PeriodicalIF":3.1,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of a high-performance tensor–matrix multiplication with BLAS

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-22 DOI: 10.1016/j.jocs.2025.102568

Cem Savaş Başsoy

{"title":"Design of a high-performance tensor–matrix multiplication with BLAS","authors":"Cem Savaş Başsoy","doi":"10.1016/j.jocs.2025.102568","DOIUrl":"10.1016/j.jocs.2025.102568","url":null,"abstract":"<div><div>The tensor–matrix multiplication (TTM) is a basic tensor operation required by various tensor methods such as the HOSVD. This paper presents flexible high-performance algorithms that compute the tensor–matrix product according to the Loops-over-GEMM (LOG) approach. The proposed algorithms can process dense tensors with any linear tensor layout, arbitrary tensor order and dimensions all of which can be runtime variable. The paper discusses two slicing methods with orthogonal parallelization strategies and propose four algorithms that call BLAS with subtensors or tensor slices. It also provides a simple heuristic which selects one of the four proposed algorithms at runtime. All algorithms have been evaluated on a large set of tensors with various tensor shapes and linear tensor layouts. In case of large tensor slices, our best-performing algorithm achieves a median performance of 2.47 TFLOPS on an Intel Xeon Gold 5318Y and 2.93 TFLOPS an AMD EPYC 9354. Furthermore, it outperforms batched GEMM implementation of Intel MKL by a factor of 2.57 with large tensor slices. Our runtime tests show that our best-performing algorithm is, on average, at least 6.21% and up to 334.31% faster than frameworks implementing state-of-the-art approaches, including actively developed libraries such as Libtorch and Eigen. For the majority of tensor shapes, it is on par with TBLIS which uses optimized kernels for the TTM computation. Our algorithm performs better than all other competing implementations for the majority of real world tensors from the SDRBench, reaching a speedup of 2x or more for some tensor instances. This work is an extended version of ”Fast and Layout-Oblivious Tensor–Matrix Multiplication with BLAS” (Başsoy 2024).</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102568"},"PeriodicalIF":3.1,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of new CORDIC algorithms implemented on FPGA for the Givens Rotator

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-21 DOI: 10.1016/j.jocs.2025.102567

Pawel Poczekajlo , Leonid Moroz , Ewa Deelman , Pawel Gepner

引用次数: 0

A numerical investigation of convection-dominated convection diffusion problems using characteristic stabilized mixed finite element method

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-21 DOI: 10.1016/j.jocs.2025.102578

Baowei Lai , Lanxin Sun , Wenhuan Yang , Lixiang Yu , Zelian Ni , Zhifeng Weng

{"title":"A numerical investigation of convection-dominated convection diffusion problems using characteristic stabilized mixed finite element method","authors":"Baowei Lai , Lanxin Sun , Wenhuan Yang , Lixiang Yu , Zelian Ni , Zhifeng Weng","doi":"10.1016/j.jocs.2025.102578","DOIUrl":"10.1016/j.jocs.2025.102578","url":null,"abstract":"<div><div>In this paper, we propose a characteristic stabilized mixed finite element method based on the lower regularity of the flux for convection dominated convection diffusion problems. The method combines the characteristic method with a stabilized mixed finite element method that uses the lowest equal-order pair for the velocity and pressure. The stabilization term is based on two local Gauss integrations for the velocity. Moreover, we obtain that the approximation of the pressure <span><math><mi>u</mi></math></span> is optimal in the <span><math><msup><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-norm and <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span>-norm, the approximation of the velocity <span><math><mi>p</mi></math></span> is suboptimal in the <span><math><msup><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-norm. Finally, numerical experiments in 2D and 3D are presented to verify the theoretical results.</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102578"},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cutting voxel projector a new approach to construct 3D cone beam CT operator

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-20 DOI: 10.1016/j.jocs.2025.102573

Vojtěch Kulvait , Julian Moosmann , Georg Rose

{"title":"Cutting voxel projector a new approach to construct 3D cone beam CT operator","authors":"Vojtěch Kulvait , Julian Moosmann , Georg Rose","doi":"10.1016/j.jocs.2025.102573","DOIUrl":"10.1016/j.jocs.2025.102573","url":null,"abstract":"<div><div>We introduce a novel class of projectors for 3D cone beam tomographic reconstruction. Analytical formulas are derived to compute the relationship between the volume of a voxel projected onto a detector pixel and its contribution to the line integral of attenuation recorded by that pixel. Based on these formulas, we construct a near-exact projector and backprojector, particularly suited for algebraic reconstruction techniques and hierarchical reconstruction approaches with nonuniform voxel grids. Unlike traditional projectors, which assume a uniform grid with fixed voxel sizes, our method enables local refinement of voxels, allowing for adaptive grid resolution and improved reconstruction quality in regions of interest. We have implemented this cutting voxel projector along with a relaxed, speed-optimized version and compared them to two established projectors: a ray-tracing projector based on Siddon’s algorithm and a TT footprint projector. Our results demonstrate that the cutting voxel projector achieves higher accuracy than the TT projector, especially for large cone beam angles. Furthermore, the relaxed version of the cutting voxel projector offers a significant speed advantage, while maintaining comparable accuracy. In contrast, Siddon’s algorithm, tuned to achieve the same accuracy, is considerably slower than the cutting voxel projector. All algorithms are implemented in a GPU optimized open-source framework for algebraic reconstruction.</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102573"},"PeriodicalIF":3.1,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Physics-informed neural networks for microflows: Rarefied gas dynamics in cylinder arrays

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-20 DOI: 10.1016/j.jocs.2025.102575

Jean-Michel Tucny , Marco Lauricella , Mihir Durve , Gianmarco Guglielmo , Andrea Montessori , Sauro Succi

{"title":"Physics-informed neural networks for microflows: Rarefied gas dynamics in cylinder arrays","authors":"Jean-Michel Tucny , Marco Lauricella , Mihir Durve , Gianmarco Guglielmo , Andrea Montessori , Sauro Succi","doi":"10.1016/j.jocs.2025.102575","DOIUrl":"10.1016/j.jocs.2025.102575","url":null,"abstract":"<div><div>Accurate prediction of rarefied gas dynamics is crucial for optimizing flows through microelectromechanical systems, air filtration devices, and shale gas extraction. Traditional methods, such as discrete velocity and direct simulation Monte Carlo (DSMC), demand intensive memory and computation, especially for microflows in non-convex domains. Recently, physics-informed neural networks (PINNs) emerged as a meshless and adaptable alternative for solving non-linear partial differential equations. We trained a PINN using a limited number of DSMC-generated rarefied gas microflows in the transition regime <span><math><mrow><mo>(</mo><mn>0.1</mn><mspace></mspace><mo><</mo><mi>Kn</mi><mo><</mo><mspace></mspace><mn>3</mn><mo>)</mo></mrow></math></span>, incorporating continuity and Cauchy momentum exchange equations in the loss function. The PINN achieved under 2 % error on these residuals and effectively filtered DSMC’s intrinsic statistical noise. Predictions remained strong for a tested flow field with <span><math><mrow><mi>Kn</mi><mo>=</mo><mn>0.7</mn></mrow></math></span>, and showed limited extrapolation performance on a flow field with <span><math><mrow><mi>Kn</mi><mo>=</mo><mspace></mspace><mn>5</mn></mrow></math></span> with a local overshoot of about 20 %, while maintaining physical consistency. Notably, each DSMC field required <span><math><mrow><mo>∼</mo><mn>20</mn></mrow></math></span> hours on 4 graphics processing units (GPU), while the PINN training took <span><math><mrow><mo><</mo><mn>2</mn></mrow></math></span> hours on one GPU, with evaluations under <span><math><mn>2</mn></math></span> seconds.</div></div>","PeriodicalId":48907,"journal":{"name":"Journal of Computational Science","volume":"87 ","pages":"Article 102575"},"PeriodicalIF":3.1,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

State, parameters and hidden dynamics estimation with the Deep Kalman Filter: Regularization strategies

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-20 DOI: 10.1016/j.jocs.2025.102569

Erik Chinellato, Fabio Marcuzzi

引用次数: 0

Energy dissipation preserving physics informed neural network for Allen–Cahn equations

IF 3.1 3区计算机科学

Journal of Computational Science Pub Date : 2025-03-20 DOI: 10.1016/j.jocs.2025.102577

Mustafa Kütük, Hamdullah Yücel

引用次数: 0