Theoretical and Computational Acoustics Ictca '99(with CD-Rom): Proceedings of the 4th International Conference Stazione Marittima, Trieste, Italy, 10-14 May 1999

The ICTCA conference provides an interdisciplinary forum for active researchers in academia and industry who are of varying backgrounds to discuss the state-of-the-art developments and results in theoretical and computational acoustics and related topics. The papers presented at the meeting cover acoustical problems of common interest across disciplines and their accurate mathematical and numerical modelling. The present book collects papers that were presented at the 4th meeting and printed in "The Journal of Computational Acoustics". There are about 120 full research articles on various subjects, such as wave propagation theory and numerical modelling, sound propagation, vibrations and noise generation, underwater acoustics, engineering seismology, ultrasonic field synthesis and modelling, as well as computational methods, inverse problems and tomography, shallow water acoustics and environmental/bottom parameter extraction. A CD-Rom is attached that allows readers to browse through articles and print those of interest to them. Preface......Page 6 CONTENTS......Page 8 Wave Propagation Theory......Page 20 Uniformly Asymptotic Solutions for Pseudodifferential Equations with Singular Integral Operators......Page 22 The Kirchhoff-Helmholtz Integral Pair......Page 23 Analysis and Processing of Received Signals in Boreholes......Page 24 Informational Capacity of Acoustic Measurements......Page 25 Resonances of Acoustic Waves Interacting with an Elastic Seabed......Page 26 Modeled Velocity and Reflectivity Properties of Anisotropic Hydrated Sediments......Page 27 Reflection/Transmission Coefficients at a Plane Interface in Dissipative and Nondissipative Isotropic Media: A Comparison......Page 28 Analysis of the Reflection and Transmission Coefficients in Three-Phase Sandstone Reservoirs......Page 29 Fractional Diffusive Waves......Page 30 Acoustic Excitation of Scholte-Stoneley and Lamb Waves on a Reinforced Cylindrical Shell......Page 31 On the Adiabaticity of Acoustic Propagation Through Nongradual Ocean Structures......Page 32 Ferromagnets and Kelvin's Medium: Basic Equations and Wave Processes......Page 33 Propagation of Ultrasonic Waves in Nonlinear Multilayered Media......Page 34 Optimal Model for the Diffraction Effect in the Ultrasonic Field of Piston Transducers......Page 35 Oblique Acoustic Axes in Trigonal Crystals......Page 36 Acoustic Time Series Variability and Time Reversal Mirror Defocusing Due To Cumulative Effects Of Water Column Variability......Page 37 Numerical and Experimental Time-Reversal of Acoustic Waves in Random Media......Page 38 Fluctuations of Elastic Waves Due to Random Scattering from Inclusions......Page 39 Numerical Study of the Wave Instability Problem with the Effect of the Transverse Velocity Component......Page 40 Sound Propagation Vibrations and Noise......Page 42 Airborne Acoustics of Explosive Volcanic Eruptions......Page 44 Sound Generation of Interacting Perturbed Vortex Rings......Page 45 A Wide-Angle Parabolic Equation for Acoustic Waves in Inhomogeneous Moving Media: Applications to Atmospheric Sound Propagation......Page 46 Acoustics of Kinematically Complex Shear Flows......Page 47 Ultrasound Propagation Through a Rotational Flow: Numerical Methods Compared to Experiments......Page 48 Wave Propagation on an Elastic Beam Traveling in a Tube: Linear Theory of Aerodynamic Loading......Page 49 On the Vibration of Membrane Partially Protruding Above the Surface of Liquid......Page 50 Vibrational Analysis of Ships with Coupled Finite and Boundary Elements......Page 51 Transverse Resonant Oscillations in Acoustic Ducts......Page 52 Noise Shielding by Simple Barriers: Comparison Between the Performance of Spherical and Line Sound Sources......Page 53 Wave Propagation Through Hollow Bodies and Noise Reduction......Page 54 Generation of Ground Elastic Waves by Road Vehicles......Page 55 Underwater Acoustics......Page 56 Broadband Matched-Field Localization Performance in Uncertain Environments Using a Short Array......Page 58 A Frequency Domain Inversion Method Applied to Oblique Reflected Signals from a Water-Sediment Interface......Page 59 Application of a Three-Dimensional Two-Way Parabolic Equation Model for Reconstructing Images of Underwater Targets......Page 60 Determination of a Buried Object in a Two-Layered Shallow Ocean......Page 61 New Schemes of Ocean Acoustic Tomography......Page 62 Numerical Simulation of Transverse Current Monitoring in the Pram Strait......Page 63 Prospects for Medium-Scale Diffraction Tomography on the Shelf......Page 64 Engineering Seismology......Page 66 Applications of the Modal Summation Technique to the Theoretical Site Response Estimation......Page 68 Earthquake Ground Motion Simulation Through the 2-D Spectral Element Method......Page 69 The Variational Indirect Boundary Element Method: A Strategy Toward the Solution of Very Large Problems of Site Response......Page 70 Efficiency and Optimization of the 3-D Finite-Difference Modeling of Seismic Ground Motion......Page 71 Three-Dimensional Ground Motion Simulations for Large Earthquakes on the San Andreas Fault with Dynamic and Observational Constraints......Page 72 Modifications of the Ground Motion in Dense Urban Areas......Page 73 Numerical Simulations of Strong Ground Motion During Destructive Earthquakes in Hokkaido Japan......Page 74 Application of the Integral Laguerre Transforms for Forward Seismic Modeling......Page 75 Parallel 3D Fourier Spectral Simulation of Strong Ground Motion in Osaka Basin During the 1995 Kobe Earthquake......Page 76 Ultrasonic Field Synthesis and Modelling......Page 78 Speed-Accuracy Trade-Offs in Computing Spatial Impulse Responses for Simulating Medical Ultrasound Imaging......Page 80 Mechanism of Acoustic Wave Propagation: A Real Role of Virtual Sources......Page 81 Synthesis of Unequally Spaced Arrays with Asymmetric Beam Patterns......Page 82 Real-Time Deconvolution in Ultrasonic Imaging Systems......Page 83 Time Reversal in Acoustics......Page 84 Computation of the Ultrasonic Field Radiated by Segmented-Annular Arrays......Page 85 Numerical Techniques for Modeling Doppler Ultrasound Spectra Systems......Page 86 Influence of the Inter-Element Coupling on Ultrasound Array Radiation Patterns......Page 87 Computational Methods......Page 88 A Direct Discrete Formulation for the Wave Equation......Page 90 An Hexahedral Face Element Method for the Displacement Formulation of Structural Acoustics Problems......Page 91 A Comparison of Numerical Methods for Active Sonar Array Performance......Page 92 On the Efficient Implementation of the Integral Equation Method in Elastodynamics......Page 93 A Generalized Mode Matching Method for Scattering Problems with Unbounded Obstacles......Page 94 AILU for Helmholtz Problems: A New Preconditioner Based on the Analytic Parabolic Factorization......Page 95 Application of a Domain Decomposition Method with Lagrange Multipliers to Acoustic Problems Arising from the Automotive Industry......Page 96 Visualization of the Energy Flow in and Around a Fluid Loaded Elastic Sphere......Page 97 Noise Prediction Based on the Spectral Method for Solving a Dissipative Boundary Value Problem in Acoustics and Its Numerical Realization......Page 98 Sine Solution of the Shallow Water Equations......Page 99 Finite Elements for Wave Problems......Page 100 Numerical Studies of Conjugated Infinite Elements for Acoustical Radiation......Page 102 A Reflection Free Boundary Condition for Propagation in Uniform Flow Using Mapped Infinite Wave Envelope Elements......Page 103 A Review of Infinite Element Methods for Exterior Helmholtz Problems......Page 104 On Fundamental Aspects of Exterior Approximations with Infinite Elements......Page 105 Finite Element Solution of Two-Dimensional Acoustic Scattering Problems Using Arbitrarily Shaped Convex Artificial Boundaries......Page 106 Third-Order Doubly Asymptotic Approximations for Computational Acoustics......Page 107 Analytical and Numerical Studies of a Finite Element PML for the Helmholtz Equation......Page 108 Continued-Fraction Absorbing Boundary Conditions for the Wave Equation......Page 109 Optimal Local Nonreflecting Boundary Conditions for Time-Dependent Waves......Page 110 Mixed Finite Elements with Mass-Lumping for the Transient Wave Equation......Page 111 Short Wave Modelling Using Special Finite Elements......Page 112 A Numerical Comparison of Finite Element Methods for the Helmholtz Equation......Page 113 Efficient Computation of Multi-Frequency Far-Field Solutions of the Helmholtz Equation Using Pade Approximation......Page 114 An Iterative Time-Stepping Method for Solving First-Order Time Dependent Problems and Its Application to the Wave Equation......Page 115 Wave Propagation Modeling......Page 116 Fictitious Domains Mixed Finite Elements and Perfectly Matched Layers for 2-D Elastic Wave Propagation......Page 118 Higher-Order Mass-Lumped Finite Elements for the Wave Equation......Page 119 Numerical Study of Elastic Wave Scattering by Cracks or Inclusions Using the Boundary Integral Equation Method......Page 120 Finite-Difference Modeling in Media with Many Small-Scale Cracks......Page 121 Scale and Angle Dependent Reflection Properties of Self-Similar Interfaces......Page 122 Elastic Waves Generated by High-Speed Trains......Page 123 Adaptive Finite Element Techniques for the Acoustic Wave Equation......Page 124 Wave Propagation in 2-D Elastic Media Using a Spectral Element Method with Triangles and Quadrangles......Page 125 A Comparative Study of Explicit Differential Operators on Arbitrary Grids......Page 126 A High-Order Fast Marching Scheme for the Linearized Eikonal Equation......Page 127 Frequency Domain Wave Propagation Modeling in Exploration Seismology......Page 128 Three-Dimensional Time Domain Modeling of Ultrasonic Wave Propagation in Concrete in Explicit Consideration of Aggregates and Porosity......Page 129 Time Domain Modeling of Axisymmetric Wave Propagation in Isotropic Elastic Media with Cent - Cylindrical Elastodynamic Finite Integration Technique......Page 130 On the Propagation of Acoustic Pulses in Porous Rigid Media: A Time-Domain Approach......Page 131 Triangle-Quadrangle Grid Method for Poroelastic Elastic and Acoustic Wave Equations......Page 132 Absorbing Layer via Wave-Equation Splitting......Page 133 Optimised Absorbing Boundary Conditions for Elastic-Wave Propagation......Page 134 Conjugated Infinite Elements for Two-Dimensional Time-Harmonic Elastodynamics......Page 135 Inverse Problems and Tomography......Page 136 Reconstruction of Layered Elastic Bottom Characteristics by the Frequency Dependence of Sound Reflectivity......Page 138 Joint 3D Traveltime Inversion of P S and Converted Waves......Page 139 Complete Families and Rayleigh Obstacles......Page 140 A Simple Regularization Method for Solving Acoustical Inverse Scattering Problems......Page 141 The Use of the Herglotz Function Method to Reconstruct Obstacles from Real and from Synthetic Scattering Data......Page 142 Nonlinear Inversion of Piezoelectrical Transducer Impedance Data......Page 143 An Algorithm for the Fully Nonlinear Inverse Scattering Problem at Fixed Frequency......Page 144 Maximum Likelihood Inversion of Active Reverberation for Boundary Localization on a Moving Sonar Platform......Page 145 Mathematical Simulation in Diffraction Acoustical Tomography with Multielement Transceiver......Page 146 Radial Ultrasonic Tomography Technique as a New Method of Flaw Imaging......Page 147 Multiresolution in 3D Seismic Tomography Within Physical Limits......Page 148 Geoacoustic Inversion in Shallow Water......Page 150 Objective Functions for Ocean Acoustic Inversion Derived by Likelihood Methods......Page 152 Deductive Multi-Tone Inversion of Seabed Parameters......Page 153 Tomographic Inversion for Geoacoustic Parameters in Shallow Water......Page 154 Matched Field Tomographic Inversion to Determine Range Dependent Geoacoustic Properties......Page 155 Identifying Modal Arrivals in Shallow Water for Bottom Geoacoustic Inversions......Page 156 Geoacoustic Tomography: Range Dependent Inversions on a Single Slice......Page 157 Nonlinear Soliton Interaction with Acoustic Signals: Focusing Effects......Page 158 Seafloor Properties Determination from Acoustic Backscattering at Normal Incidence with a Parametric Source......Page 159