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Numerical Analysis of Bacterial Meningitis Stochastic Delayed Epidemic Model through Computational Methods
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作者 Umar Shafique Mohamed Mahyoub Al-Shamiri +3 位作者 Ali Raza Emad Fadhal Muhammad Rafiq Nauman Ahmed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期311-329,共19页
Based on theWorld Health Organization(WHO),Meningitis is a severe infection of the meninges,the membranes covering the brain and spinal cord.It is a devastating disease and remains a significant public health challeng... Based on theWorld Health Organization(WHO),Meningitis is a severe infection of the meninges,the membranes covering the brain and spinal cord.It is a devastating disease and remains a significant public health challenge.This study investigates a bacterial meningitis model through deterministic and stochastic versions.Four-compartment population dynamics explain the concept,particularly the susceptible population,carrier,infected,and recovered.The model predicts the nonnegative equilibrium points and reproduction number,i.e.,the Meningitis-Free Equilibrium(MFE),and Meningitis-Existing Equilibrium(MEE).For the stochastic version of the existing deterministicmodel,the twomethodologies studied are transition probabilities and non-parametric perturbations.Also,positivity,boundedness,extinction,and disease persistence are studiedrigorouslywiththe helpofwell-known theorems.Standard and nonstandard techniques such as EulerMaruyama,stochastic Euler,stochastic Runge Kutta,and stochastic nonstandard finite difference in the sense of delay have been presented for computational analysis of the stochastic model.Unfortunately,standard methods fail to restore the biological properties of the model,so the stochastic nonstandard finite difference approximation is offered as an efficient,low-cost,and independent of time step size.In addition,the convergence,local,and global stability around the equilibria of the nonstandard computational method is studied by assuming the perturbation effect is zero.The simulations and comparison of the methods are presented to support the theoretical results and for the best visualization of results. 展开更多
关键词 Bacterial Meningitis disease stochastic delayed model stability analysis extinction and persistence computational methods
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Applications of Soft Computing Methods in Backbreak Assessment in Surface Mines: A Comprehensive Review
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作者 Mojtaba Yari Manoj Khandelwal +3 位作者 Payam Abbasi Evangelos I.Koutras Danial Jahed Armaghani Panagiotis G.Asteris 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2207-2238,共32页
Geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them effecti... Geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them effectively.Soft Computing(SC)methods have gained popularity in engineering disciplines such as mining and civil engineering due to computer hardware and machine learning advancements.Unlike traditional hard computing approaches,SC models use soft values and fuzzy sets to navigate uncertain environments.This study focuses on the application of SC methods to predict backbreak,a common issue in blasting operations within mining and civil projects.Backbreak,which refers to the unintended fracturing of rock beyond the desired blast perimeter,can significantly impact project timelines and costs.This study aims to explore how SC methods can be effectively employed to anticipate and mitigate the undesirable consequences of blasting operations,specifically focusing on backbreak prediction.The research explores the complexities of backbreak prediction and highlights the potential benefits of utilizing SC methods to address this challenging issue in geo-engineering projects. 展开更多
关键词 Backbreak BLASTING soft computing methods prediction theory-guided machine learning
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Fast and Accurate Predictor-Corrector Methods Using Feedback-Accelerated Picard Iteration for Strongly Nonlinear Problems
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作者 Xuechuan Wang Wei He +1 位作者 Haoyang Feng Satya N.Atluri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1263-1294,共32页
Although predictor-corrector methods have been extensively applied,they might not meet the requirements of practical applications and engineering tasks,particularly when high accuracy and efficiency are necessary.A no... Although predictor-corrector methods have been extensively applied,they might not meet the requirements of practical applications and engineering tasks,particularly when high accuracy and efficiency are necessary.A novel class of correctors based on feedback-accelerated Picard iteration(FAPI)is proposed to further enhance computational performance.With optimal feedback terms that do not require inversion of matrices,significantly faster convergence speed and higher numerical accuracy are achieved by these correctors compared with their counterparts;however,the computational complexities are comparably low.These advantages enable nonlinear engineering problems to be solved quickly and accurately,even with rough initial guesses from elementary predictors.The proposed method offers flexibility,enabling the use of the generated correctors for either bulk processing of collocation nodes in a domain or successive corrections of a single node in a finite difference approach.In our method,the functional formulas of FAPI are discretized into numerical forms using the collocation approach.These collocated iteration formulas can directly solve nonlinear problems,but they may require significant computational resources because of the manipulation of high-dimensionalmatrices.To address this,the collocated iteration formulas are further converted into finite difference forms,enabling the design of lightweight predictor-corrector algorithms for real-time computation.The generality of the proposed method is illustrated by deriving new correctors for three commonly employed finite-difference approaches:the modified Euler approach,the Adams-Bashforth-Moulton approach,and the implicit Runge-Kutta approach.Subsequently,the updated approaches are tested in solving strongly nonlinear problems,including the Matthieu equation,the Duffing equation,and the low-earth-orbit tracking problem.The numerical findings confirm the computational accuracy and efficiency of the derived predictor-corrector algorithms. 展开更多
关键词 Predictor-corrector method feedback-accelerated Picard iteration nonlinear dynamical system real-time computation
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Computational fluid dynamics-discrete element method simulation of stirred tank reactor for graphene production
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作者 Shuaishuai Zhou Jing Li +5 位作者 Kaixiang Pang Chunxi Lu Feng Zhu Congzhen Qiao Yajie Tian Jingwei Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期196-207,共12页
Liquid phase exfoliation(LPE)process for graphene production is usually carried out in stirred tank reactor and the interactions between the solvent and the graphite particles are important as to improve the productio... Liquid phase exfoliation(LPE)process for graphene production is usually carried out in stirred tank reactor and the interactions between the solvent and the graphite particles are important as to improve the production efficiency.In this paper,these interactions were revealed by computational fluid dynamics–discrete element method(CFD-DEM)method.Based on simulation results,both liquid phase flow hydrodynamics and particle motion behavior have been analyzed,which gave the general information of the multiphase flow behavior inside the stirred tank reactor as to graphene production.By calculating the threshold at the beginning of graphite exfoliation process,the shear force from the slip velocity was determined as the active force.These results can support the optimization of the graphene production process. 展开更多
关键词 computational fluid dynamics Discrete element method Stirred tank LPE process Liquid-particle interactions
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Predicting Genotype Information Related to COVID-19 for Molecular Mechanism Based on Computational Methods 被引量:1
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作者 Lejun Gong Xingxing Zhang +1 位作者 Li Zhang Zhihong Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第10期31-45,共15页
Novel coronavirus disease 2019(COVID-19)is an ongoing health emergency.Several studies are related to COVID-19.However,its molecular mechanism remains unclear.The rapid publication of COVID-19 provides a new way to el... Novel coronavirus disease 2019(COVID-19)is an ongoing health emergency.Several studies are related to COVID-19.However,its molecular mechanism remains unclear.The rapid publication of COVID-19 provides a new way to elucidate its mechanism through computational methods.This paper proposes a prediction method for mining genotype information related to COVID-19 from the perspective of molecular mechanisms based on machine learning.The method obtains seed genes based on prior knowledge.Candidate genes are mined from biomedical literature.The candidate genes are scored by machine learning based on the similarities measured between the seed and candidate genes.Furthermore,the results of the scores are used to perform functional enrichment analyses,including KEGG,interaction network,and Gene Ontology,for exploring the molecular mechanism of COVID-19.Experimental results show that the method is promising for mining genotype information to explore the molecular mechanism related to COVID-19. 展开更多
关键词 COVID-19 SARS-CoV-2 computational method BIOINFORMATICS GENOTYPE machine learning
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A Parallel Computational Scheme on Hybrid Methods
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作者 Zhao ShuangsuoDepartment of Mathematics, Lanzhou University, Lanzhou 730000Wang ChangyinInst. of Mech. & Elec. Eng., Gansu University of Technology, Lanzhou 730050 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第4期8-18,共11页
Based on the efficient hybrid methods for solving initial value problems of stiff ODEs, this paper derives a parallel scheme that can be used to solve the problems on parallel computers with N processors, and discusse... Based on the efficient hybrid methods for solving initial value problems of stiff ODEs, this paper derives a parallel scheme that can be used to solve the problems on parallel computers with N processors, and discusses the iteratively B-convergence of the Newton iterative process, finally, the paper provides some numberical results which show that the parallel scheme is highly efficient as N is not too large. 展开更多
关键词 Hybrid methods Parallel computation Iteratively B-convergence.
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Computational multiscale methods for granular materials
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作者 Xikui Li Yuanbo Liang +2 位作者 Youyao Du Ke Wan Qinglin Duan 《Theoretical & Applied Mechanics Letters》 CAS 2013年第1期1-10,共10页
The fine-scale heterogeneity of granular material is characterized by its polydisperse microstructure with randomness and no periodicity. To predict the mechanical response of the material as the microstructure evolve... The fine-scale heterogeneity of granular material is characterized by its polydisperse microstructure with randomness and no periodicity. To predict the mechanical response of the material as the microstructure evolves, it is demonstrated to develop computational multiscale methods using discrete particle assembly-Cosserat continuum modeling in micro- and macro- scales,respectively. The computational homogenization method and the bridge scale method along the concurrent scale linking approach are briefly introduced. Based on the weak form of the Hu-Washizu variational principle, the mixed finite element procedure of gradient Cosserat continuum in the frame of the second-order homogenization scheme is developed. The meso-mechanically informed anisotropic damage of effective Cosserat continuum is characterized and identified and the microscopic mechanisms of macroscopic damage phenomenon are revealed. c 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi: 10.1063/2.1301101] 展开更多
关键词 granular material discrete particle assembly gradient Cosserat continuum computational homogenization bridge scale method damage characterization
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Bio-Inspired Computational Methods for the Polio Virus Epidemic Model
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作者 Fatimah Abdulrahman Alrawajeh F.M.Allehiany +4 位作者 Ali Raza Shaimaa A.M.Abdelmohsen Tahir Nawaz Cheema Muhammad Rafiq Muhammad Mohsin 《Computers, Materials & Continua》 SCIE EI 2022年第8期2357-2374,共18页
In 2021,most of the developing countries are fighting polio,and parents are concerned with the disabling of their children.Poliovirus transmits from person to person,which can infect the spinal cord,and paralyzes the ... In 2021,most of the developing countries are fighting polio,and parents are concerned with the disabling of their children.Poliovirus transmits from person to person,which can infect the spinal cord,and paralyzes the parts of the body within a matter of hours.According to the World Health Organization(WHO),18 million currently healthy people could have been paralyzed by the virus during 1988–2020.Almost all countries but Pakistan,Afghanistan,and a fewmore have been declared polio-free.The mathematical modeling of poliovirus is studied in the population by categorizing it as susceptible individuals(S),exposed individuals(E),infected individuals(I),and recovered individuals(R).In this study,we study the fundamental properties such as positivity and boundedness of the model.We also rigorously study the model’s stability and equilibria with or without poliovirus.For numerical study,we design the Euler,Runge–Kutta,and nonstandard finite difference method.However,the standard techniques are time-dependent and fail to present the results for an extended period.The nonstandard finite difference method works well to study disease dynamics for a long time without any constraints.Finally,the results of different methods are compared to prove their effectiveness. 展开更多
关键词 POLIOVIRUS modeling stability results computational methods
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Application of computational methods in genetic study ofinflammatory bowel disease 被引量:2
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作者 Jin Li Zhi Wei Hakon Hakonarson 《World Journal of Gastroenterology》 SCIE CAS 2016年第3期949-960,共12页
Genetic factors play an important role in the etiology of inflammatory bowel disease(IBD). The launch of genome-wide association study(GWAS) represents a landmark in the genetic study of human complex disease. Concurr... Genetic factors play an important role in the etiology of inflammatory bowel disease(IBD). The launch of genome-wide association study(GWAS) represents a landmark in the genetic study of human complex disease. Concurrently, computational methods have undergone rapid development during the past a few years, which led to the identification of numerous disease susceptibility loci. IBD is one of the successful examples of GWAS and related analyses. A total of 163 genetic loci and multiple signaling pathways have been identified to be associated with IBD. Pleiotropic effects were found for many of these loci; and risk prediction models were built based on a broad spectrum of genetic variants. Important gene-gene, gene-environment interactions and key contributions of gut microbiome are being discovered. Here we will review the different types of analyses that have been applied to IBD genetic study, discuss the computational methods for each type of analysis, and summarize the discoveries made in IBD research with the application of these methods. 展开更多
关键词 Inflammatory BOWEL disease computationalmethods GENOME-WIDE association study Pathwayanalysis Gene-gene INTERACTION Gene-environmentinteraction PLEIOTROPY Risk prediction
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Computational Complex Method for Finite Elastic Plane Problem with Multiple Elliptical Holes 被引量:2
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作者 王林江 林佳铿 《应用基础与工程科学学报》 EI CSCD 1998年第4期5-12,共8页
把多复变量应力函数和边界配点最小二乘法相结合,计算含有任意多个椭圆孔有限大小弹性板的应力场.每个孔的大小、位置为任意.板的边界由下列四种边界条件以及它们的组合所组成:1)已知Px和Py的应力边界,2)已知Vx和Vy的... 把多复变量应力函数和边界配点最小二乘法相结合,计算含有任意多个椭圆孔有限大小弹性板的应力场.每个孔的大小、位置为任意.板的边界由下列四种边界条件以及它们的组合所组成:1)已知Px和Py的应力边界,2)已知Vx和Vy的位移边界,3)已知法向位移VN和切向力PT的混合边界,4)已知法向力PN和切向位移VT的混合边界.编制了相应的FORTRAN程序,进行考题和算例分析,结果表明本方法行之有效. 展开更多
关键词 弹性板孔 应力分析 计算复变函数
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Direct computing methods for turn flows in traffic assignment
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作者 任刚 王炜 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期225-228,共4页
Two methods based on a slight modification of the regular traffic assignmentalgorithms are proposed to directly compute turn flows instead of estimating them from link flows orobtaining them by expanding the networks.... Two methods based on a slight modification of the regular traffic assignmentalgorithms are proposed to directly compute turn flows instead of estimating them from link flows orobtaining them by expanding the networks. The first one is designed on the path-turn incidencerelationship, and it is similar to the computational procedure of link flows. It applies to thetraffic assignment algorithms that can provide detailed path structures. The second utilizes thelink-turn incidence relationship and the conservation of flow on links, a law deriving from thisrelationship. It is actually an improved version of Dial's logit assignment algorithm. The proposedapproaches can avoid the shortcomings both of the estimation methods, e. g. Furness's model andFrator's model, and of the network-expanding method in precision, stability and computation scale.Finally, they are validated by numerical examples. 展开更多
关键词 turn flow traffic assignment Dial's algorithm directly computing method
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A computational method for post-construction settlement of high-speed railway bridge pile foundation considering soil creep effect 被引量:12
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作者 冯胜洋 魏丽敏 +1 位作者 何重阳 何群 《Journal of Central South University》 SCIE EI CAS 2014年第7期2921-2927,共7页
Based on reasonable assumptions that simplified the calculational model,a simple and practical method was proposed to calculate the post-construction settlement of high-speed railway bridge pile foundation by using th... Based on reasonable assumptions that simplified the calculational model,a simple and practical method was proposed to calculate the post-construction settlement of high-speed railway bridge pile foundation by using the Mesri creep model to describe the soil characteristics and the Mindlin-Geddes method considering pile diameter to calculate the vertical additional stress of pile bottom.A program named CPPS was designed for this method to calculate the post-construction settlement of a high-speed railway bridge pile foundation.The result indicates that the post-construction settlement in 100 years meets the requirements of the engineering specifications,and in the first two decades,the post-construction settlement is about 80% of its total settlement,while the settlement in the rest eighty years tends to be stable.Compared with the measured settlement after laying railway tracks,the calculational result is closed to that of the measured,and the results are conservative with a high computational accuracy.It is noted that the method can be used to calculate the post-construction settlement for the preliminary design of high-speed railway bridge pile foundation. 展开更多
关键词 high-speed railway bridge pile foundation post-construction settlement Mesri creep model simplified computational method
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A Single Image Derain Method Based on Residue Channel Decomposition in Edge Computing
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作者 Yong Cheng Zexuan Yang +3 位作者 Wenjie Zhang Ling Yang Jun Wang Tingzhao Guan 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1469-1482,共14页
The numerous photos captured by low-price Internet of Things(IoT)sensors are frequently affected by meteorological factors,especially rainfall.It causes varying sizes of white streaks on the image,destroying the image... The numerous photos captured by low-price Internet of Things(IoT)sensors are frequently affected by meteorological factors,especially rainfall.It causes varying sizes of white streaks on the image,destroying the image texture and ruining the performance of the outdoor computer vision system.Existing methods utilise training with pairs of images,which is difficult to cover all scenes and leads to domain gaps.In addition,the network structures adopt deep learning to map rain images to rain-free images,failing to use prior knowledge effectively.To solve these problems,we introduce a single image derain model in edge computing that combines prior knowledge of rain patterns with the learning capability of the neural network.Specifically,the algorithm first uses Residue Channel Prior to filter out the rainfall textural features then it uses the Feature Fusion Module to fuse the original image with the background feature information.This results in a pre-processed image which is fed into Half Instance Net(HINet)to recover a high-quality rain-free image with a clear and accurate structure,and the model does not rely on any rainfall assumptions.Experimental results on synthetic and real-world datasets show that the average peak signal-to-noise ratio of the model decreases by 0.37 dB on the synthetic dataset and increases by 0.43 dB on the real-world dataset,demonstrating that a combined model reduces the gap between synthetic data and natural rain scenes,improves the generalization ability of the derain network,and alleviates the overfitting problem. 展开更多
关键词 Single image derain method edge computing residue channel prior feature fusion module
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Computer Methodologies for the Comparison of Some Efficient Derivative FreeSimultaneous Iterative Methods for Finding Roots of Non-Linear Equations 被引量:1
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作者 Yuming Chu Naila Rafiq +3 位作者 Mudassir Shams Saima Akram Nazir Ahmad Mir Humaira Kalsoom 《Computers, Materials & Continua》 SCIE EI 2021年第1期275-290,共16页
In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Conver... In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature. 展开更多
关键词 Non-linear equation iterative method simultaneous method basins of attractions computational efficiency
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A fast computational method for the landing footprints of space-to-ground vehicles 被引量:2
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作者 LIU Qingguo LIU Xinxue +1 位作者 WU Jian LI Yaxiong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期1062-1076,共15页
Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer tra... Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer trajectories. In order to address the usually slow computational time for the determination of the landing footprint of a space-to-ground vehicle under finite thrust, this work proposes a method that uses polynomial equations to describe the boundaries of the landing footprint and uses back propagation(BP) neural networks to quickly determine the landing footprint of the space-to-ground vehicle. First, given orbital parameters and a manoeuvre moment, the solution model of the landing footprint of a space-to-ground vehicle under finite thrust is established. Second, given arbitrary orbital parameters and an arbitrary manoeuvre moment, a fast computational model for the landing footprint of a space-to-ground vehicle based on BP neural networks is provided.Finally, the simulation results demonstrate that under the premise of ensuring accuracy, the proposed method can quickly determine the landing footprint of a space-to-ground vehicle with arbitrary orbital parameters and arbitrary manoeuvre moments. The proposed fast computational method for determining a landing footprint lays a foundation for the parking-orbit configuration and supports the design of real-time transfer trajectories. 展开更多
关键词 space-to-ground vehicle landing footprint back propagation(BP)neural network fast computational method Pontryagin's minimum principle
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Review:Recent Development of High⁃Order⁃Spectral Method Combined with Computational Fluid Dynamics Method for Wave⁃Structure Interactions 被引量:1
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作者 Yuan Zhuang Decheng Wan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第3期170-188,共19页
The present paper reviews the recent developments of a high⁃order⁃spectral method(HOS)and the combination with computational fluid dynamics(CFD)method for wave⁃structure interactions.As the numerical simulations of wa... The present paper reviews the recent developments of a high⁃order⁃spectral method(HOS)and the combination with computational fluid dynamics(CFD)method for wave⁃structure interactions.As the numerical simulations of wave⁃structure interaction require efficiency and accuracy,as well as the ability in calculating in open sea states,the HOS method has its strength in both generating extreme waves in open seas and fast convergence in simulations,while computational fluid dynamics(CFD)method has its advantages in simulating violent wave⁃structure interactions.This paper provides the new thoughts for fast and accurate simulations,as well as the future work on innovations in fine fluid field of numerical simulations. 展开更多
关键词 potential⁃viscous flow high⁃order⁃spectral(HOS)method computational fluid dynamics(CFD)method
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Hybrid Prediction Method for Solar Power Using Different Computational Intelligence Algorithms 被引量:1
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作者 Md Rahat Hossain Amanullah Maung Than Oo A. B. M. Shawkat Ali 《Smart Grid and Renewable Energy》 2013年第1期76-87,共12页
Computational Intelligence (CI) holds the key to the development of smart grid to overcome the challenges of planning and optimization through accurate prediction of Renewable Energy Sources (RES). This paper presents... Computational Intelligence (CI) holds the key to the development of smart grid to overcome the challenges of planning and optimization through accurate prediction of Renewable Energy Sources (RES). This paper presents an architectural framework for the construction of hybrid intelligent predictor for solar power. This research investigates the applicability of heterogeneous regression algorithms for 6 hour ahead solar power availability forecasting using historical data from Rockhampton, Australia. Real life solar radiation data is collected across six years with hourly resolution from 2005 to 2010. We observe that the hybrid prediction method is suitable for a reliable smart grid energy management. Prediction reliability of the proposed hybrid prediction method is carried out in terms of prediction error performance based on statistical and graphical methods. The experimental results show that the proposed hybrid method achieved acceptable prediction accuracy. This potential hybrid model is applicable as a local predictor for any proposed hybrid method in real life application for 6 hours in advance prediction to ensure constant solar power supply in the smart grid operation. 展开更多
关键词 computational INTELLIGENCE HETEROGENEOUS Regressions Algorithms Performance Evaluation HYBRID method Mean ABSOLUTE Scaled Error (MASE)
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Complementary memtransistors for neuromorphic computing: How, what and why
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作者 Qi Chen Yue Zhou +4 位作者 Weiwei Xiong Zirui Chen Yasai Wang Xiangshui Miao Yuhui He 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期64-80,共17页
Memtransistors in which the source-drain channel conductance can be nonvolatilely manipulated through the gate signals have emerged as promising components for implementing neuromorphic computing.On the other side,it ... Memtransistors in which the source-drain channel conductance can be nonvolatilely manipulated through the gate signals have emerged as promising components for implementing neuromorphic computing.On the other side,it is known that the complementary metal-oxide-semiconductor(CMOS)field effect transistors have played the fundamental role in the modern integrated circuit technology.Therefore,will complementary memtransistors(CMT)also play such a role in the future neuromorphic circuits and chips?In this review,various types of materials and physical mechanisms for constructing CMT(how)are inspected with their merits and need-to-address challenges discussed.Then the unique properties(what)and poten-tial applications of CMT in different learning algorithms/scenarios of spiking neural networks(why)are reviewed,including super-vised rule,reinforcement one,dynamic vision with in-sensor computing,etc.Through exploiting the complementary structure-related novel functions,significant reduction of hardware consuming,enhancement of energy/efficiency ratio and other advan-tages have been gained,illustrating the alluring prospect of design technology co-optimization(DTCO)of CMT towards neuro-morphic computing. 展开更多
关键词 complementary memtransistor neuromorphic computing reward-modulated spike timing-dependent plasticity remote supervise method in-sensor computing
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Neural Network Robust Control Based on Computed Torque for Lower Limb Exoskeleton
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作者 Yibo Han Hongtao Ma +6 位作者 Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期83-99,共17页
The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.Complex modeling errors of the exoskeleton in different application scenarios pose challenges to the ... The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.Complex modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its control algorithm.The Radial Basis Function(RBF)neural network is used widely to compensate for modeling errors.In order to solve the problem that the current RBF neural network controllers cannot guarantee the asymptotic stability,a neural network robust control algorithm based on computed torque method is proposed in this paper,focusing on trajectory tracking.It innovatively incorporates the robust adaptive term while introducing the RBF neural network term,improving the compensation ability for modeling errors.The stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the simulation.Experiments wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are consistently less than 1.5°and 2.5°,respectively.The proposed control algorithm effectively compensates for modeling errors and exhibits high robustness. 展开更多
关键词 Lower limb exoskeleton Model compensation RBF neural network computed torque method
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A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone
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作者 Huiqing Liu Heping Xie +2 位作者 Fei Wu Cunbao Li Renbo Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期479-489,共11页
Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media withi... Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these rocks.Faced with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric perspective.By employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock models.The improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore distribution.Further numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute permeability.The results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission properties.The methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks. 展开更多
关键词 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation computational geosciences
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