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1 Classical Continuous Models and Their Analysis |
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1 | (38) |
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1 | (9) |
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1.1.1 The Acoustics Equation |
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2 | (1) |
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1.1.2 Maxwell's Equations |
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2 | (4) |
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1.1.3 The Linear Elastodynamics System |
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6 | (2) |
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1.1.4 Boundary Conditions |
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8 | (2) |
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10 | (20) |
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1.2.1 Some Functional Spaces |
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10 | (6) |
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1.2.2 Variational Formulations |
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16 | (4) |
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20 | (2) |
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1.2.4 Well-Posedness Results of Waves Equations |
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22 | (8) |
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30 | (9) |
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1.3.1 A General Solution of the Homogeneous Wave Equation |
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30 | (2) |
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1.3.2 Application to Maxwell's Equations |
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32 | (2) |
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34 | (1) |
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1.3.4 Application to the Isotropic Linear Elastodynamics System |
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35 | (1) |
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36 | (3) |
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2 Definition of Different Types of Finite Elements |
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39 | (56) |
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2.1 1D Mass-Lumping and Spectral Elements |
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39 | (8) |
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2.1.1 A Complex Solution for a Simple Problem |
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39 | (2) |
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41 | (4) |
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45 | (1) |
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2.1.4 Nodal and Modal Elements |
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46 | (1) |
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2.2 Quadrilaterals and Hexahedra |
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47 | (5) |
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2.2.1 Higher-Dimensional Tensor Quadrature Rules |
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47 | (1) |
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2.2.2 Tensor Unit Spectral Elements |
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48 | (2) |
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2.2.3 Extension to Quadrilaterals and Hexahedra |
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50 | (2) |
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2.3 Triangles and Tetrahedra |
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52 | (9) |
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2.3.1 Spectral Triangles and Tetrahedra |
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52 | (5) |
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2.3.2 Mass-Lumped Triangles and Tetrahedra |
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57 | (4) |
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61 | (6) |
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62 | (1) |
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62 | (5) |
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2.5 Tetrahedral and Triangular Edge Elements |
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67 | (12) |
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67 | (1) |
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67 | (4) |
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71 | (2) |
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2.5.4 Tetrahedral Mass-Lumped Edge Elements |
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73 | (3) |
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2.5.5 Triangular Mass-Lumped Edge Elements |
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76 | (3) |
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2.6 Hexahedral and Quadrilateral Edge Elements |
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79 | (5) |
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79 | (3) |
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82 | (2) |
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2.7 H(div) Finite Elements |
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84 | (4) |
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2.7.1 Tetrahedral and Triangular Elements |
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84 | (2) |
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2.7.2 Hexahedral and Quadrilateral Elements |
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86 | (2) |
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88 | (7) |
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2.8.1 Pyramidal and Prismatic Edge Elements |
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88 | (2) |
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2.8.2 Pyramidal and Prismatic H(div) Elements |
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90 | (1) |
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91 | (4) |
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3 Hexahedral and Quadrilateral Spectral Elements for Acoustic Waves |
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95 | (80) |
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3.1 Second-Order Formulation of the Acoustics Equation |
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95 | (5) |
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3.1.1 The Continuous and Approximate Problem |
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95 | (1) |
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3.1.2 Discretization of the Integrals |
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96 | (4) |
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3.2 First-Order Formulation of the Acoustics Equation |
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100 | (6) |
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3.2.1 The Mixed Formulation |
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101 | (1) |
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102 | (1) |
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3.2.3 The Stiffness Matrices |
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103 | (3) |
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3.3 Comparison of the Methods |
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106 | (6) |
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106 | (1) |
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3.3.2 A Theorem of Equivalence |
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107 | (2) |
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3.3.3 Comparison of the Costs |
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109 | (3) |
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112 | (23) |
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3.4.1 The Continuous Equation |
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113 | (1) |
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3.4.2 A Didactic Case: The Pi Approximation |
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113 | (3) |
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3.4.3 The Concept of Numerical Dispersion |
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116 | (1) |
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117 | (3) |
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3.4.5 P3 and Higher-Order Approximations |
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120 | (6) |
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3.4.6 Extension to Higher Dimensions |
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126 | (9) |
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3.5 Reflection-Transmission by a Discontinuous Interface |
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135 | (10) |
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3.5.1 The Continuous Problem |
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135 | (1) |
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3.5.2 FEM Approximation of the Heterogeneous Wave Equation |
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136 | (1) |
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3.5.3 Taylor Expansion of the Wavenumber |
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137 | (1) |
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3.5.4 Interface Between Two Elements |
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138 | (1) |
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3.5.5 Interface at an Interior Point |
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139 | (1) |
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3.5.6 Extension to Higher-Order Approximations |
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140 | (1) |
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3.5.7 A Two-Layer Experiment |
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141 | (4) |
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3.6 hp-a priori Error Estimates |
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145 | (21) |
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3.6.1 Some Properties of Meshes |
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146 | (2) |
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3.6.2 Some Interpolation Errors for Quadrilaterals and Hexahedra |
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148 | (4) |
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3.6.3 hp-Estimation of Numerical Integration Errors |
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152 | (7) |
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3.6.4 hp a priori Error Estimate for the Semi-discrete Approximation |
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159 | (7) |
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3.7 The Linear Elastodynamics System |
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166 | (9) |
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3.7.1 Second Order Formulation |
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166 | (1) |
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3.7.2 First-Order Formulation |
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167 | (3) |
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3.7.3 Comparison of the Two Approaches |
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170 | (3) |
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173 | (2) |
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4 Discontinuous Galerkin Methods |
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175 | (58) |
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4.1 General Formulation for Linear Hyperbolic Problems |
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175 | (13) |
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4.1.1 The Discontinuous Galerkin Formulation |
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175 | (6) |
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181 | (3) |
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4.1.3 Application to Some Wave Equations |
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184 | (4) |
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4.2 Approximation by Triangles and Tetrahedra |
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188 | (9) |
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189 | (2) |
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4.2.2 The Stiffness Integrals |
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191 | (2) |
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193 | (4) |
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4.3 Approximation by Quadrilaterals and Hexahedra |
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197 | (10) |
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197 | (1) |
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4.3.2 The Stiffness Integrals |
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198 | (1) |
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199 | (2) |
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4.3.4 Application to Wave Equations |
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201 | (6) |
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4.4 Comparison of the DG Methods for Maxwell's Equations |
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207 | (11) |
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4.4.1 Gauss or Gauss--Lobatto? |
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207 | (3) |
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4.4.2 Tetrahedra with and Without Reconstruction of the Stiffness Matrix |
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210 | (1) |
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4.4.3 Tetrahedra Versus Hexahedra |
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210 | (8) |
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218 | (8) |
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4.5.1 The Eigenvalue Problem for the 1D Model |
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218 | (3) |
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4.5.2 Numerical Dispersion and Dissipation |
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221 | (3) |
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4.5.3 Extension to Higher Dimensions |
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224 | (2) |
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4.6 Interior Penalty Discontinuous Galerkin Methods |
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226 | (7) |
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4.6.1 General Formulation |
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226 | (2) |
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4.6.2 Coercivity of the Discrete Operator |
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228 | (4) |
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232 | (1) |
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5 The Maxwell's System and Spurious Modes |
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233 | (52) |
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5.1 A First Model and Its Approximation |
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233 | (4) |
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5.1.1 The Continuous Model |
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233 | (1) |
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5.1.2 The Approximate Model |
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234 | (1) |
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5.1.3 The Discrete Mass Integral |
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235 | (2) |
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5.2 A Second Model and Its Approximations |
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237 | (8) |
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5.2.1 The Continuous Model |
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237 | (1) |
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5.2.2 General Formulations of the Approximations |
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238 | (1) |
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5.2.3 Approximation in H(Curl, Ω) |
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239 | (1) |
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5.2.4 Approximation in [ H1(Ω)]3 |
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240 | (2) |
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5.2.5 Comparison of the Approximations |
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242 | (3) |
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5.3 Suppressing Spurious Modes |
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245 | (18) |
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5.3.1 Some Background About the Spurious Modes |
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245 | (7) |
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5.3.2 Computation of the Eigenvalues of × × on a Cube |
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252 | (3) |
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5.3.3 Discontinuous Galerkin Methods |
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255 | (3) |
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5.3.4 The Second Family of Edge Elements |
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258 | (3) |
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5.3.5 Continuous Elements |
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261 | (1) |
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5.3.6 The Case of the First Family of Edge Elements |
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261 | (2) |
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5.4 Error Estimates for DGM |
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263 | (22) |
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5.4.1 The Discontinuous Galerkin Formulation |
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263 | (1) |
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5.4.2 Choice of a Projector |
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264 | (3) |
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5.4.3 hp-Projection Errors |
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267 | (4) |
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271 | (2) |
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5.4.5 A Priori Error Estimates in Energy Norm |
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273 | (7) |
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5.4.6 Extension to the Dissipative Case |
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280 | (2) |
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282 | (3) |
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6 Approximating Unbounded Domains |
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285 | (30) |
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6.1 Absorbing Boundary Conditions (ABC) |
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286 | (11) |
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6.1.1 Transparent Condition of the Wave Equation |
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286 | (1) |
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6.1.2 Construction of ABC for the Wave Equation |
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287 | (4) |
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6.1.3 Plane Wave Analysis |
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291 | (1) |
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6.1.4 Finite Element Implementation |
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292 | (4) |
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6.1.5 The Maxwell's System |
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296 | (1) |
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6.2 Perfectly Matched Layers (PML) |
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297 | (18) |
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6.2.1 Interpretation of the Method |
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297 | (3) |
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6.2.2 The Acoustics System |
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300 | (6) |
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6.2.3 The Maxwell's System |
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306 | (2) |
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6.2.4 The Linear Elastodynamics System |
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308 | (2) |
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310 | (2) |
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312 | (3) |
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315 | (40) |
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7.1 Schemes with a Constant Time-Step |
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315 | (19) |
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7.1.1 Construction of the Schemes |
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316 | (4) |
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7.1.2 Stability of the Schemes by Plane Wave Analysis |
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320 | (5) |
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7.1.3 Stability of the Schemes by Energy Techniques |
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325 | (2) |
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7.1.4 The Modified Equation and Unbounded Domains |
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327 | (3) |
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7.1.5 A Remark About the Time Approximation of Dissipative DG Schemes |
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330 | (4) |
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334 | (21) |
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7.2.1 Symplectic Schemes for Conservative Approximations |
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335 | (5) |
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7.2.2 Scheme Based on a Lagrange Multiplier |
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340 | (6) |
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7.2.3 An Explicit Conservative Scheme for Second-Order Wave Equations |
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346 | (7) |
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353 | (2) |
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355 | |
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8.1 The Linearized Euler Equations |
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355 | (9) |
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8.1.1 Discontinuous Galerkin Approximation |
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356 | (4) |
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8.1.2 H1-L2 Approximation |
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360 | (4) |
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8.2 The Linear Cauchy--Poisson Problem |
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364 | (8) |
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8.2.1 The Continuous Problem and Its Approximation |
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364 | (3) |
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367 | (5) |
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8.3 Vibrating Thin Plates |
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372 | |
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8.3.1 The Continuous Models |
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373 | (1) |
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8.3.2 Plane Wave Analysis |
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374 | (4) |
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8.3.3 Mixed Spectral Element Approximation |
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378 | (2) |
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380 | |