Ebook: Applied partial differential equations

Preface to the Third Edition -- To Students -- 1: The Physical Origins of Partial Differential Equations -- 1.1 PDE Models -- 1.2 Conservation Laws -- 1.3 Diffusion -- 1.4 Diffusion and Randomness -- 1.5 Vibrations and Acoustics -- 1.6 Quantum Mechanics@* -- 1.7 Heat Conduction in Higher Dimensions -- 1.8 Laplace's Equation -- 1.9 Classification of PDEs -- 2. Partial Differential Equations on Unbounded Domains -- 2.1 Cauchy Problem for the Heat Equation -- 2.2 Cauchy Problem for the Wave Equation -- 2.3 Well-Posed Problems -- 2.4 Semi-Infinite Domains -- 2.5 Sources and Duhamel's Principle -- 2.6 Laplace Transforms -- 2.7 Fourier Transforms -- 3. Orthogonal Expansions -- 3.1 The Fourier Method -- 3.2 Orthogonal Expansions -- 3.3 Classical Fourier Series.-4. Partial Differential Equations on Bounded Domains -- 4.1 Overview of Separation of Variables -- 4.2 Sturm-Liouville Problems -- 4.3 Generalization and Singular Problems -- 4.4 Laplace's Equation -- 4.5 Cooling of a Sphere -- 4.6 Diffusion inb a Disk -- 4.7 Sources on Bounded Domains -- 4.8 Poisson's Equation@*.-5. Applications in the Life Sciences.-5.1 Age-Structured Models -- 5.2 Traveling Waves Fronts -- 5.3 Equilibria and Stability -- 6. Numerical computation of solutions -- 6.1 Finite Difference Approximation -- 6.2 Explicit Scheme for the Heat Equation -- 6.3 Laplace's Equation -- 6.4 Implicit Scheme for the Heat Equation -- References -- Appendix A. Differential Equations -- Index.;This text presents the standard material usually covered in a one-semester, undergraduate course on boundary value problems and PDEs. Emphasis is placed on motivation, concepts, methods, and interpretation, rather than on formal theory. The concise treatment of the subject is maintained in this third edition covering all the major ideas: the wave equation, the diffusion equation, the Laplace equation, and the advection equation on bounded and unbounded domains. Methods include eigenfunction expansions, integral transforms, and characteristics. In this third edition, text remains intimately tied to applications in heat transfer, wave motion, biological systems, and a variety other topics in pure and applied science.