We consider the vertex-centered finite volume method with first-order conforming ansatz functions. The adaptive mesh-refinement is driven by the local contributions of the weighted residual error estimator. We prove t...
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We consider the vertex-centered finite volume method with first-order conforming ansatz functions. The adaptive mesh-refinement is driven by the local contributions of the weighted residual error estimator. We prove that the adaptive algorithm leads to linear convergence with generically optimal algebraic rates for the error estimator and the sum of energy error plus data oscillations. While similar results have been derived for finite element methods and boundary element methods, the present work appears to be the first for adaptive finite volume methods, where the lack of the classical Galerkin orthogonality leads to new challenges.
We present an algorithm for the adaptive tetrahedral integration over the Brillouin zone of crystalline materials, and apply it to compute the optical conductivity, dc conductivity, and thermopower. For these quantiti...
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We present an algorithm for the adaptive tetrahedral integration over the Brillouin zone of crystalline materials, and apply it to compute the optical conductivity, dc conductivity, and thermopower. For these quantities, whose contributions are often localized in small portions of the Brillouin zone, adaptive integration is especially relevant. Our implementation, the woptic package, is tied into the WIEN2WANNIER framework and allows including a local many-body self energy, e.g. from dynamical mean-field theory (DMFT). Wannier functions and dipole matrix elements are computed with the DFT package WIEN2k and Wannier90. For illustration, we show DFT results for fcc-Al and DMFT results for the correlated metal SrVO3. (C) 2016 Elsevier B.V. All rights reserved.
An adaptive multi-penalty discontinuous Galerkin method(AMPDG)for the diffusion problem is *** and quasi-optimality of the AM-PDG are *** with the analyses for the adaptive finite element method or the adaptive interi...
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An adaptive multi-penalty discontinuous Galerkin method(AMPDG)for the diffusion problem is *** and quasi-optimality of the AM-PDG are *** with the analyses for the adaptive finite element method or the adaptive interior penalty discontinuous Galerkin method,extra works are done to overcome the difficulties caused by the additional penalty terms.
作者：
Yang HaitianHan ZhiHe YiqianDalian Univ Technol
Dept Engn Mech State Key Lab Struct Anal Ind Equipment Dalian 116024 Peoples R China MEP
Dept Nucl & Radiat Safety Res Nucl & Radiat Safety Ctr Beijing 100082 Peoples R China
This paper presents a new numerical approach for the static and dynamic stabilities analysis of viscoelastic columns. By expanding all variables in a discretized time interval, a time and space coupled integral-differ...
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This paper presents a new numerical approach for the static and dynamic stabilities analysis of viscoelastic columns. By expanding all variables in a discretized time interval, a time and space coupled integral-differential equation system is converted into a series of recursive spatial problems that are solved via FEM. A temporally piecewised adaptive algorithm is developed to maintain computing accuracy. Consequently, the descriptions of static stability of imperfect viscoelastic columns and dynamic stability of perfect viscoelastic columns are realized, respectively. Numerical examples are presented to verify the proposed approach. Additionally, two analytical expressions are derived for the dynamic stability analysis of linear and Burgers models, respectively. Copyright (C) 2016 John Wiley & Sons, Ltd.
Hybrid storage systems that consist of flash-based solid state drives (SSDs) and traditional disks are now widely used. In hybrid storage systems, there exists a two-level cache hierarchy that regard dynamic random ac...
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Hybrid storage systems that consist of flash-based solid state drives (SSDs) and traditional disks are now widely used. In hybrid storage systems, there exists a two-level cache hierarchy that regard dynamic random access memory (DRAM) as the first level cache and SSD as the second level cache for disk storage. However, this two-level cache hierarchy typically uses independent cache replacement policies for each level, which makes cache resource management inefficient and reduces system performance. In this paper, we propose a novel adaptive multi-level cache (AMC) replacement algorithm in hybrid storage systems. The AMC algorithmadaptively adjusts cache blocks between DRAM and SSD cache levels using an integrated solution. AMC uses combined selective promote and demote operations to dynamically determine the level in which the blocks are to be cached. In this manner, the AMC algorithm achieves multi-level cache exclusiveness and makes cache resource management more efficient. By using real-life storage traces, our evaluation shows the proposed algorithm improves hybrid multi-level cache performance and also increases the SSD lifetime compared with traditional multi-level cache replacement algorithms. Copyright (c) 2015 John Wiley & Sons, Ltd.
A piecewised adaptive algorithm in the time domain is presented to solve the transient convection-diffusion heat transfer problem. By expanding all variables at a time interval, an initial and boundary value problem i...
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A piecewised adaptive algorithm in the time domain is presented to solve the transient convection-diffusion heat transfer problem. By expanding all variables at a time interval, an initial and boundary value problem is decoupled into a series of recursive boundary value problems which can be solved by FEM or other well developed numerical schemes to deal with boundary value problems. A steady computing accuracy can be adaptively maintained via the power increase of the expansion, particularly when the step size varies in the whole computing process. Additionally for the nonlinear cases, there is no requirement of iteration and additional assumption for the proposed algorithm. Three numerical examples are provided to verify the presented algorithm,and satisfactory results have been achieved.
An improved compensation method for an all-standard-cell voltage-controlled oscillator (VCO)-based ADC is presented in this Letter. The proposed compensation uses closed-form orthogonal polynomials bases instead of po...
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An improved compensation method for an all-standard-cell voltage-controlled oscillator (VCO)-based ADC is presented in this Letter. The proposed compensation uses closed-form orthogonal polynomials bases instead of power series ones. With these more powerful bases, the cross interaction between different basis is eliminated which leads to better resolution, lower order of compensation series, and shorter convergence time of the adaptive algorithm.
This paper presents an adaptive algorithm in the time domain for the dynamic analysis of a simply supported beam subjected to the moving load and moving vehicle with/without varying surface roughness. By expanding var...
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This paper presents an adaptive algorithm in the time domain for the dynamic analysis of a simply supported beam subjected to the moving load and moving vehicle with/without varying surface roughness. By expanding variables at a discretized time interval, a coupled spatial-temporal problem can be converted into a series of recursive space problems that are solved by finite element method (FEM), and a piecewised adaptive computing procedure can be carried out for different sizes of time steps. The proposed approach is numerically verified via the comparison with analytical and the Runge-Kutta method-based solutions, and satisfactory results have been achieved. Copyright (C) 2011 John Wiley & Sons, Ltd.
Technology of maximum power point tracking(MPPT)is the key technological problem for light volt *** paper studies a type of adaptive weight inertia variation cat swarm algorithm,which is realized by photovoltaic batte...
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Technology of maximum power point tracking(MPPT)is the key technological problem for light volt *** paper studies a type of adaptive weight inertia variation cat swarm algorithm,which is realized by photovoltaic battery output voltage and the load voltage matching control,and achieves the maximum power output in the power *** curves with multiple peak values present under the interference of numerous complex *** article expounds the algorithm solved the partial shade of multiplex mode optimization problems which is unable to realize by the traditional *** to realize the maximum power point tracking is the key research for quasi-Z-source inverters in Photovoltaic *** is proved that the feasibility of the improved algorithm proposed and the advantages of high speed and precision in tracking build mathematical model used commonly through the MATLAB/Simulink.
A simple method for the computation of 3D scatterers remotely located from the source with layered media is presented. This domain decomposition method is based on the total-field/scattered-field formulation of the 3D...
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A simple method for the computation of 3D scatterers remotely located from the source with layered media is presented. This domain decomposition method is based on the total-field/scattered-field formulation of the 3D finite-difference in time-domain method. The electromagnetic field along the propagation path is not directly involved;it focuses only on the electromagnetic field in the surroundings of the scatterer. The incident electromagnetic field radiated from the source is computed separately with an adaptive algorithm and then applied on the Huygens' surface, leading to the proposed hybridisation technique.
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