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| 1 | Artificial Neural Network Methods for the Solution of Second Order Boundary Value Problems显示文摘We present a method for solving partial differential equations using artificial neural networks and an adaptive collocation strategy.In this procedure,a coarse grid of training points is used at the initial training stages,while more points are added at later stages based on the value of the residual at a larger set of evaluation points.This method increases the robustness of the neural network approximation and can result in significant computational savings,particularly when the solution is non-smooth.Numerical results are presented for benchmark problems for scalar-valued PDEs,namely Poisson and Helmholtz equations,as well as for an inverse acoustics problem. | Cosmin Anitescu Elena Atroshchenko Naif Alajlan Timon Rabczuk | 2019 | Computers, Materials & Continua2019，，4： | 72 |
| 2 | A Deep Collocation Method for the Bending Analysis of Kirchhoff Plate显示文摘In this paper,a deep collocation method(DCM)for thin plate bending problems is proposed.This method takes advantage of computational graphs and backpropagation algorithms involved in deep learning.Besides,the proposed DCM is based on a feedforward deep neural network(DNN)and differs from most previous applications of deep learning for mechanical problems.First,batches of randomly distributed collocation points are initially generated inside the domain and along the boundaries.A loss function is built with the aim that the governing partial differential equations(PDEs)of Kirchhoff plate bending problems,and the boundary/initial conditions are minimised at those collocation points.A combination of optimizers is adopted in the backpropagation process to minimize the loss function so as to obtain the optimal hyperparameters.In Kirchhoff plate bending problems,the C^1 continuity requirement poses significant difficulties in traditional mesh-based methods.This can be solved by the proposed DCM,which uses a deep neural network to approximate the continuous transversal deflection,and is proved to be suitable to the bending analysis of Kirchhoff plate of various geometries. | Hongwei Guo Xiaoying Zhuang Timon Rabczuk | 2019 | Computers, Materials & Continua2019，，5： | 53 |
| 3 | A Nonlocal Operator Method for Partial Differential Equations with Application to Electromagnetic Waveguide Problem显示文摘A novel nonlocal operator theory based on the variational principle is proposed for the solution of partial differential equations.Common differential operators as well as the variational forms are defined within the context of nonlocal operators.The present nonlocal formulation allows the assembling of the tangent stiffness matrix with ease and simplicity,which is necessary for the eigenvalue analysis such as the waveguide problem.The present formulation is applied to solve the differential electromagnetic vector wave equations based on electric fields.The governing equations are converted into nonlocal integral form.An hourglass energy functional is introduced for the elimination of zeroenergy modes.Finally,the proposed method is validated by testing three classical benchmark problems. | Timon Rabczuk Huilong Ren Xiaoying Zhuang | 2019 | Computers, Materials & Continua2019，，4： | 28 |
| 4 | Role of human papillomavirus in oropharyngeal squamous cell carcinoma: A review显示文摘Human papillomavirus(HPV) has been implicated in the pathogenesis of a subset of oropharyngeal squamous cell carcinoma. As a result, traditional paradigms in relation to the management of head and neck squamous cell carcinoma have been changing. Research into HPVrelated oropharyngeal squamous cell carcinoma is rapidly expanding, however many molecular pathological and clinical aspects of the role of HPV remain uncertain and are the subject of ongoing investigation. A detailed search of the literature pertaining to HPV-related oropharyngeal squamous cell carcinoma was performed and information on the topic was gathered. In this article, we present an extensive review of the current literature on the role of HPV in oropharyngeal squamous cell carcinoma, particularly in relation to epidemiology, risk factors, carcinogenesis, biomarkers and clinicalimplications. HPV has been established as a causative agent in oropharyngeal squamous cell carcinoma and biologically active HPV can act as a prognosticator with better overall survival than HPV-negative tumours. A distinct group of younger patients with limited tobacco and alcohol exposure have emerged as characteristic of this HPV-related subset of squamous cell carcinoma of the head and neck. However, the exact molecular mechanisms of carcinogenesis are not completely understood and further studies are needed to assist development of optimal prevention and treatment modalities. | Robbie SR Woods Esther M O'Regan Susan Kennedy Cara Martin John J O'Leary Conrad Timon | 2014 | World Journal of Clinical Cases2014，2，6： | 5 |
| 5 | Computational model generation and RVE design o self-healing concrete显示文摘Computational homogenization is a versatile tool that can extract effective properties of heterogeneous or composite material through averaging technique. Self-healing concrete (SHC) is a heterogeneous material which has different constituents as cement matrix, sand and healing agent carrying capsules. Computational homogenization tool is applied in this paper to evaluate the effective properties of self-healing concrete. With this technique, macro and micro scales are bridged together which forms the basis for multi-scale modeling. Representative volume element (RVE) is a small (microscopic) cell which contains all the microphases of the microstructure. This paper presents a technique for RVE design of SHC and shows the influence of volume fractions of different constituents, RVE size and mesh uniformity on the homogenization results. | Md. Shahriar QUAYUM Xiaoying ZHUANG Timon RABCZUK | 2015 | Frontiers of Structural and Civil Engineering2015，9，4： | 5 |
| 6 | Computational Machine Learning Representation for the Flexoelectricity Effect in Truncated Pyramid Structures显示文摘In this study,machine learning representation is introduced to evaluate the flexoelectricity effect in truncated pyramid nanostructure under compression.A Non-Uniform Rational B-spline(NURBS)based IGA formulation is employed to model the flexoelectricity.We investigate 2D system with an isotropic linear elastic material under plane strain conditions discretized by 45×30 grid of B-spline elements.Six input parameters are selected to construct a deep neural network(DNN)model.They are the Young's modulus,two dielectric permittivity constants,the longitudinal and transversal flexoelectric coefficients and the order of the shape function.The outputs of interest are the strain in the stress direction and the electric potential due flexoelectricity.The dataset are generated from the forward analysis of the flexoelectric model.80%of the dataset is used for training purpose while the remaining is used for validation by checking the mean squared error.In addition to the input and output layers,the developed DNN model is composed of four hidden layers.The results showed high predictions capabilities of the proposed method with much lower computational time in comparison to the numerical model. | Khader M.Hamdia Hamid Ghasemi Xiaoying Zhuang Naif Alajlan Timon Rabczuk | 2019 | Computers, Materials & Continua2019，，4： | 5 |
| 7 | Optimizing the neural network hyperparameters utilizing genetic algorithm显示文摘Neural networks(NNs),as one of the most robust and efficient machine learning methods,have been commonly used in solving several problems.However,choosing proper hyperparameters(e.g.the numbers of layers and neurons in each layer)has a significant influence on the accuracy of these methods.Therefore,a considerable number of studies have been carried out to optimize the NN hyperpaxameters.In this study,the genetic algorithm is applied to NN to find the optimal hyperpaxameters.Thus,the deep energy method,which contains a deep neural network,is applied first on a Timoshenko beam and a plate with a hole.Subsequently,the numbers of hidden layers,integration points,and neurons in each layer are optimized to reach the highest accuracy to predict the stress distribution through these structures.Thus,applying the proper optimization method on NN leads to significant increase in the NN prediction accuracy after conducting the optimization in various examples. | Saeid NIKBAKHT Cosmin ANITESCU Timon RABCZUK | 2021 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2021，22，6： | 5 |
| 8 | A Dual-Support Smoothed Particle Hydrodynamics for Weakly Compressible Fluid Inspired By the Dual-Horizon Peridynamics显示文摘A dual-support smoothed particle hydrodynamics(DS-SPH)that allows variable smoothing lengths while satisfying the conservations of linear momentum,angular momentum and energy is developed.The present DS-SPH is inspired by the dual-support,a concept introduced from dual-horizon peridynamics from the authors and applied here to SPH so that the unbalanced interactions between the particles with different smoothing lengths can be correctly considered and computed.Conventionally,the SPH formulation employs either the influence domain or the support domain.The concept of dual-support identifies that the influence domain and the support domain involves the duality and should be simultaneously in the SPH formulation when variable smoothing lengths are used.The DS-SPH formulation can be implemented into conventional SPH codes with minimal changes and also without compromising the computational efficiency.A number of numerical examples involving weakly compressible.fluid are presented to demonstrate the capability of the method. | Huilong Ren Xiaoying Zhuang Timon Rabczuk | 2019 | Computer Modeling in Engineering & Sciences2019，，11： | 4 |
| 9 | High velocity impact of metal sphere on thin metallic plate using smooth particle hydrodynamics(SPH)method显示文摘The modeling of high velocity impact is an important topic in impact engineering.Due to various constraints,experimental data are extremely limited.Therefore,detailed numerical simulation can be considered as a desirable alternative.However,the physical processes involved in the impact are very sophisticated;hence a practical and complete reproduction of the phenomena involves complicated numerical models.In this paper,we present a smoothed particle hydrodynamics(SPH)method to model two-dimensional impact of metal sphere on thin metallic plate.The simulations are applied to different materials(Aluminum,Lead and Steel);however the target and projectile are formed of similar metals.A wide range of velocities(300,1000,2000,and 3100 m/s)are considered in this study.The goal is to study the most sensitive input parameters(impact velocity and plate thickness)on the longitudinal extension of the projectile,penetration depth and damage crater. | Hossein ASADI KALAMEH Arash KARAMALI Cosmin ANITESCU Timon RABCZUK | 2012 | Frontiers of Structural and Civil Engineering2012，6，2： | 4 |
| 10 | Machine-learning-driven on-demand design of phononic beams显示文摘The development of phononic crystals, especially their interaction with topological insulators, allows exploration of the anomalous properties of acoustic/elastic waves for various applications. However, rapidly and inversely exploring the geometry of specific targets remains a major challenge. In this work, we show how machine learning can address this challenge by studying phononic crystal beams using two different inverse design schemes. We first develop the theory of phononic beams using the transfer matrix method. Then, we use the reinforcement learning algorithm to effectively and inversely design the structural parameters to maximize the bandgap width. Furthermore, we employ the tandem-architecture neural network to solve the training-difficulty problem caused by inconsistent data and complete the task of inverse structure design with the targeted topological properties. The two inverse-design schemes have different adaptabilities, and both are characterized by high efficiency and stability. This work provides deep insights into the combination of machine learning, topological property,and phononic crystals and offers a reliable platform for rapidly and inversely designing complex material and structure properties. | Liangshu He Hongwei Guo Yabin Jin Xiaoying Zhuang Timon Rabczuk Yan Li | 2022 | Science China(Physics,Mechanics & Astronomy)2022，65，1： | 3 |
| 11 | Extraordinary characteristics for one-dimensional parity-time-symmetric periodic ring optical waveguide networks显示文摘In this paper, we design a one-dimensional(1D) parity-time-symmetric periodic ring optical waveguide network(PTSPROWN) and investigate its extraordinary optical characteristics. It is found that quite different from traditional vacuum/dielectric optical waveguide networks, 1D PTSPROWN cannot produce a photonic ordinary propagation mode, but can generate simultaneously two kinds of photonic nonpropagation modes: attenuation propagation mode and gain propagation mode. It creates neither passband nor stopband and possesses no photonic band structure. This makes 1D PTSPROWN possess richer spontaneous PT-symmetric breaking points and causes interesting extremum spontaneous PT-symmetric breaking points to appear, where electromagnetic waves can create ultrastrong extraordinary transmission, reflection, and localization, and the maximum can arrive at 6.6556 × 10^(12) and is more than 7 orders of magnitude larger than the results reported previously.1D PTSPROWN may possess potential in designing high-efficiency optical energy saver devices, optical amplifiers, optical switches with ultrahigh monochromaticity, and so on. | YAN ZHI XIANGBO YANG JIAYE WU SHIPING DU PEICHAO CAO DONGMEI DENG CHENGYI TIMON LIU | 2018 | Photonics Research2018，6，6： | 2 |
| 12 | Isogeometric cohesive zone model for thin shell delamination analysis based on Kirchhoff-Love shell model显示文摘We present a cohesive zone model for delamination in thin shells and composite structures.The isogeometric(IGA)thin shell model is based on Kirchhoff-Love theory.Non-Uniform Rational B-Splines(NURBS)are used to discretize the exact mid-surface of the shell geometry exploiting their C 1-continuity property which avoids rotational degrees of freedom.The fracture process zone is modeled by interface elements with a cohesive law.Two numerical examples are presented to test and validate the proposed formulation in predicting the delamination behavior of composite structures. | Tran Quoc THAI Timon RABCZUK Xiaoying ZHUANG | 2020 | Frontiers of Structural and Civil Engineering2020，14，2： | 2 |
| 13 | Three-Dimensional Isogeometric Analysis of Flexoelectricity with MATLAB Implementation显示文摘Flexoelectricity is a general electromechanical phenomenon where the electric polarization exhibits a linear dependency to the gradient of mechanical strain and vice versa.The truncated pyramid compression test is among the most common setups to estimate the flexoelectric effect.We present a three-dimensional isogeometric formulation of flexoelectricity with its MATLAB implementation for a truncated pyramid setup.Besides educational purposes,this paper presents a precise computational model to illustrate how the localization of strain gradients around pyramidal boundary shapes contributes in generation of electrical energy.The MATLAB code is supposed to help learners in the Isogeometric Analysis and Finite Elements Methods community to learn how to solve a fully coupled problem,which requires higher order approximations,numerically.The complete MATLAB code which is available as source code distributed under a BSD-style license,is provided in the part of Supplementary Materials of the paper. | Hamid Ghasemi Harold S.Park Xiaoying Zhuang Timon Rabczuk | 2020 | Computers, Materials & Continua2020，，11： | 2 |
| 14 | 汉江洪水频率计算不确定性分析(Ⅰ):流量测量阶段的不确定性显示文摘洪水频率分析中的不确定性是影响设计洪水精度的主要因素,为了更全面的评价洪水频率分析中的不确定性,提高计算结果精度,使用NUSAP方法对流量测量阶段的不确定性进行了评价.首先,从总体上阐述了NUSAP方法的原理和评价机制,提出了适用于洪水频率分析领域的Ped igree矩阵,然后结合该矩阵将NUSAP方法应用于流量测量不确定性评价.结果证明NUSAP方法在对流量测量进行不确定性评价时是有效的,可以考虑进一步应用于整个洪水频率分析阶段. | 许月萍 徐晓 黄艳 Timon Klok | 2011 | 应用基础与工程科学学报2011，19，S1： | 2 |
| 15 | 汉江洪水频率计算不确定性分析(Ⅱ):统计过程不确定性显示文摘使用NUSAP方法对洪水频率分析中的两种流量序列选取方法进行不确定性评价,然后对于选用的4种分布函数,分别使用矩法和极大似然法进行参数估计,针对不同的参数估计方法以及分布函数,应用NUSAP方法结合曲线拟合误差综合评价其中的不确定性.结果表明,超阈值方法是一种较为科学的时间序列选取方法,广义柏拉图分布和PⅢ分布对流量序列的拟合结果较好.NUSAP方法对上述分布函数和各种参数估计方法的评价结果更直观、更合理,是其在洪水频率分析领域应用的一个良好开端. | 许月萍 徐晓 Timon Klok 冉启华 | 2011 | 应用基础与工程科学学报2011，19，S1： | 2 |
| 16 | Evaluation of a novel Asymmetric Genetic Algorithm to optimize the structural design of 3D regular and irregular steel frames显示文摘We propose a new algorithm,named Asymmetric Genetic Algorithm(AGA),for solving optimization problems of steel frames.The AGA consists of a developed penalty function,which helps to find the best generation of the population.The objective function is to minimize the weight of the whole steel structure under the constraint of ultimate loads defined for structural steel buildings by the American Institute of Steel Construction(AISC).Design variables are the cross-sectional areas of elements(beams and columns)that are selected from the sets of side-flange shape steel sections provided by the AISC.The finite element method(FEM)is utilized for analyzing the behavior of steel frames.A 15-storey three-bay steel planar frame is optimized by AGA in this study,which was previously optimized by algorithms such as Particle Swarm Optimization(PSO),Particle Swarm Optimizer with Passive Congregation(PSOPC),Particle Swarm Ant Colony Optimization(HPSACO),Imperialist Competitive Algorithm(ICA),and Charged System Search(CSS).The results of AGA such as total weight of the structure and number of analyses are compared with the results of these algorithms.AGA performs better in comparison to these algorithms with respect to total weight and number of analyses.In addition,five numerical examples are optimized by AGA,Genetic Algorithm(GA),and optimization modules of SAP2000,and the results of them are compared.The results show that AGA can decrease the time of analyses,the number of analyses,and the total weight of the structure.AGA decreases the total weight of regular and irregular steel frame about 11.1%and 26.4%in comparing with the optimized results of SAP2000,respectively. | Mohammad Sadegh ES-HAGHI Aydin SHISHEGARAN Timon RABCZUK | 2020 | Frontiers of Structural and Civil Engineering2020，14，5： | 2 |
| 17 | Microglial SIRPα Deletion Facilitates Synapse Loss in Preclinical Models of Neurodegeneration显示文摘Microglia,the principal immune cells in the brain,play a vital role in the development and homeostasis of the central nervous system[1,2].During early brain development,microglia-mediated synapse pruning contributes to eliminating excess synapses that are unnecessary in adulthood[3].Excessive microglia-mediated pruning in the adult brain is implicated in neurodegeneration-associated behav・ioral deficits[4,5]. | Chongyun Wu Luodan Yang Hannah Youngblood Timon Cheng-Yi Liu Rui Duan | 2022 | Neuroscience Bulletin2022，38，2： | 2 |
| 18 | Biophotonics on Low Intens-ityLa-ser显示文摘 | Liu Timon Chengy i LiuSonghao | 1997 | Chinese Journal of Laser Medicine&Surgery1997，3，6： | 1 |
| 19 | Globus pharyngeus: long-term follow-up and prognostic factors 显示文摘 | Timon C O'Dwyer T Cagney D | 1991 | Ann Otol Rhinol Laryngol1991，100，： | 1 |
| 20 | Laryngeal tuberculosis:an important diagnosis显示文摘 | Harney M Hone S Timon C | 2000 | J Laryngol Otol2000，114，： | 1 |
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