vii TABLE OF CONTENTS CHAPTER TITLE PAGE THESIS STATUS DECLARATION SUPERVISOR’S DECLARATION DECLARATION ON COOPERATION 1 TITLE PAGE i DECLARATION ii DEDICATION iii ACKNOWLEDGEMENT iv ABSTRACT v ABSTRAK vi TABLE OF CONTENTS vii LIST OF TABLES xi LIST OF FIGURES xiv LIST OF SYMBOLS xvii LIST OF APPENDICES xviii INTRODUCTION 1 1.1 Introduction 1 1.2 Background of The Problem 2 1.3 Problem Statement 5 1.4 Scope of Study 5 1.5 Research Objectives 6 1.6 Thesis Outline 7 viii 2 OVERVIEW OF MAPPING OF MULTIPLY CONNECTED REGIONS 10 2.1 Introduction 10 2.2 Ideas of Conformal Mapping 10 2.3 The Riemann Conformal Mapping 12 2.4 Conformal Mapping of Multiply Connected Regions 14 2.5 Exact Mapping Function of Doubly Connected Regions for Some Selected Regions 18 2.5.1 Annulus Onto A Disk With A Circular Slit 19 2.5.2 Circular Frame 20 2.5.3 Frame of Limacon 21 2.5.4 Elliptic Frame 22 2.5.5 Frame of Cassini’s Oval 22 2.6 Some Numerical Method for Conformal Mapping of Multiply Connected Regions 3 23 2.6.1 Wegmann’s Iterative Method 25 2.6.2 Symm’s Integral Equations 26 2.6.3 Charge Simulation Method 26 2.6.4 Mikhlin’s Integral Equation 27 2.6.5 Fredholm Integral Equation 28 2.6.6 Warschawski’s and Gershgorin’s Integral Equations 28 2.6.7 The Boundary Integral Equation via the Kerzman-Stein and the Neumann Kernels 29 AN INTEGRAL EQUATION RELATED TO A BOUNDARY RELATIONSHIP 34 3.1 Introduction 34 3.2 The Boundary Integral Equation 35 3.3 Application to Conformal Mapping of Doubly ix Connected Regions onto an Annulus via the Kerzman-Stein Kernel 3.4 Application to Conformal Mapping of Multiply Connected Regions onto an Annulus with Circular Slits via the Neumann Kernel 3.5 Application to Conformal Mapping of Multiply Connected Regions onto a Disk with Circular Slits via the Neumann Kernel 4 37 42 46 NUMERICAL CONFORMAL MAPPING OF MULTIPLY CONNECTED REGIONS ONTO AN ANNULUS WITH CIRCULAR SLITS 50 4.1 Introduction 50 4.2 Conformal Mapping of Doubly Connected Regions onto an Annulus via the Kerzman-Stein Kernel 51 4.2.1 A System of Integral Equations 51 4.2.2 Numerical Implementation 53 4.2.3 Numerical Results 57 4.3 Conformal Mapping of Doubly Connected Regions onto an Annulus via the Neumann Kernel 63 4.3.1 A System of Integral Equations 63 4.3.2 Numerical Implementation 65 4.3.3 Numerical Results 71 4.4 Conformal Mapping of Triply Connected Regions onto an Annulus with a Circular Slit Via the Neumann Kernel 86 4.4.1 A System of Integral Equations 86 4.4.2 Numerical Implementation 88 4.4.3 Interior of Triply Connected Region 95 4.4.4 Numerical Results 96 x 5 NUMERICAL CONFORMAL MAPPING OF MULTIPLY CONNECTED REGIONS ONTO A DISK WITH CIRCULAR SLITS 100 5.1 Introduction 100 5.2 Conformal Mapping of Doubly Connected Regions onto a Disk with a Circular Slit Via the Neumann Kernel 101 5.2.1 A System of Integral Equations 101 5.2.2 Numerical Implementation 103 5.2.3 The Interior Mapping 108 5.2.4 Numerical Results 109 5.3 Conformal Mapping of Triply Connected Regions onto a Disk with Circular Slits Via the Neumann Kernel 6 116 5.3.1 A System of Integral Equations 116 5.3.2 Numerical Implementation 118 5.3.3 Numerical Results 125 SUMMARY AND CONCLUSIONS 128 6.1 Summary of the Research 128 6.2 Suggestions for Future Research 131 REFERENCES 133 Appendix A Publications/Presentations 139 Appendix B 143 Sample of Computer Programs xi LIST OF TABLES TABLE NO. TITLE PAGE 4.1 Error norm of the the Example 4.1 59 4.2 Error norm of the the Example 4.1 by Murid and Mohamed (2007) 59 Error Norm of the the Example 4.1 using Amano’s method and Symm’s method 59 4.4 The radius comparison of the Example 4.2 60 4.5 The computed approximations of μ and M for the Example 4.3 62 4.6 The radius comparison of the Example 4.3 62 4.7 Error Norm of the Example 4.4 74 4.8 Error Norm of Interior for the Example 4.4 74 4.9 Error Norm of the Example 4.4 as given in Mohamed and Murid (2007b) based on the Neumann kernel 74 Error Norm of the Example 4.4 using Amano’s method and Symm’s method 75 4.11 Error Norm of the Example 4.5 76 4.12 Error Norm of Interior for the Example 4.5 76 4.13 Error Norm of the Example 4.5 as given in Mohamed and Murid (2007b) based on the Neumann kernel 77 Error norm of the Example 4.5 using Amano’s method and Symm’s method 77 Error Norm of Interior for the Example 4.5 as given in Mohamed and Murid (2007a) based on the Kerzman-Stein kernel 77 4.3 4.10 4.14 4.15 xii 4.16 Error Norm of the Example 4.6 79 4.17 Error Norm of Interior for the Example 4.6 79 4.18 Error Norm of the Example 4.6 as given in Mohamed and Murid (2007b) based on the Neumann kernel 79 4.19 Error Norm of the Example 4.6 using Symm’s method 80 4.20 Error Norm of the Example 4.7 81 4.21 Error Norm of Interior for the Example 4.7 81 4.22 Error Norm of the Example 4.7 as given in Mohamed and Murid (2007b) based on the Neumann kernel 82 4.23 The radius comparison of the Example 4.8 83 4.24 The radius comparison of the Example 4.9 84 4.25 The computed approximations of μ and M for the Example 4.10 85 4.26 The radius comparison for the Example 4.10 86 4.27 Radii comparison with Reichel (1986) for the Example 4.11 97 Radii comparison with Kokkinos et al. (1990) for Example 4.11 97 4.29 Radii comparison for Example 4.12 98 5.1 Error Norm of the Example 5.1 110 5.2 Error Norm of Interior for the Example 5.1 110 5.3 Error Norm of the Example 5.2 112 5.4 Error Norm of Interior for the Example 5.2 112 5.5 Error Norm of the Example 5.3 113 5.6 Error Norm of Interior for the Example 5.3 113 5.7 Error Norm of the Example 5.4 114 5.8 Error Norm of Interior for the Example 5.4 114 5.9 Error Norm of the Example 5.5 116 5.10 Error Norm of Interior for the Example 5.5 116 5.11 Radii comparison with Reichel (1986) for the Example 5.6 126 4.28 xiii 5.12 Radii comparison with Kokkinos et al. (1990) for the Example 5.6 126 xiv LIST OF FIGURES FIGURE NO. TITLE PAGE 1.1 Canonical regions 4 2.1 The tangents at the point z0 and w0 , where f (z) is an analytic function and f (z0 ) = 0 12 The analytic mapping w = f (z) is conformal at point z0 and w0 , where f (z0 ) = 0 and γ2 − γ1 = β2 − β1 12 2.3 Boundary Correspondence Function θ(t) 14 2.4 An (M + 1) connected region 15 2.5 Mapping of a region of connectivity 4 16 2.6 Mapping of a region of connectivity 4 onto an annulus with circular slits 16 Mapping of a region of connectivity 4 onto a disk with circular slits 17 2.8 The composite g = h ◦ f 18 2.9 The composite function g = h ◦ p 19 3.1 Mapping of a doubly connected region Ω onto an annulus 38 Mapping of doubly connected region onto an annulus 40 Mapping of a multiply connected region Ω of connectivity M + 1 onto an annulus with circular slits 42 2.2 2.7 3.2 3.3 3.4 4.1 Mapping of a multiply connected region Ω of connectivity M + 1 onto a disk with circular slits √ Mapping of the Example 4.1 with a0 = 2 14, a1 = 2, b0 = 7 and b1 = 1 47 58 xv 4.2 Mapping of the Example 4.2 60 4.3 Mapping of the Example 4.3 with a0 = 0.20 61 4.4 A rectangular grid in Ω with grid size 0.25 and √ its image with a0 = 2 14, a1 = 2, b0 = 7, and b1 = 1 for the Example 4.4 73 A rectangular grid in Ω with grid size 0.25 and its image with a0 = 7, a1 = 5, b0 = 5, and b1 = 1 for the Example 4.5 76 A rectangular grid in Ω with grid size 0.4 and its image with a0 = 10, a1 = 5, b0 = 3 and b1 = b0 /4 for the Example 4.6 78 A rectangular grid in Ω with grid size 0.05 and its image with c = 0.3 and ρ = 0.1 for the Example 4.7 81 A rectangular grid in Ω with grid size 0.25 and its image for the Example 4.8 82 A rectangular grid in Ω with grid size 0.25 and its image for the Example 4.9 83 A rectangular grid in Ω with grid size 0.05 and its image with a0 = 2.0 for the Example 4.10 85 A rectangular grid in Ω with grid size 0.05 and its image for the Example 4.11 97 A rectangular grid in Ω with grid size 0.05 and its image for the Example 4.12 98 4.13 Mapping of the Example 4.12 based on Ellacott method 99 5.1 A rectangular grid in Ω with grid size 0.05 and its image with radius μ = e−2σ for the Example 5.1 110 A rectangular grid in Ω with grid and its image with radius μ = e−2σ for the Example 5.2 111 A rectangular grid in Ω with grid size 0.4 and its image with radius μ = e−2σ for the Example 5.3 113 A rectangular grid in Ω with grid size 0.25 and its image with radius μ = e−2σ for the Example 5.4 114 A rectangular grid in with grid size 0.25 and Ω its image with radius μ = e−2σ for the Example 5.5 115 The Contour for Example 5.6 126 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 5.2 5.3 5.4 5.5 5.6 xvi 5.7 The image of the mapping for the Example 5.6 127 xvii LIST OF SYMBOLS A(z, w) - Kerzman-Stein kernel H(w, z) - Cauchy kernel N (z, w) - Neumann kernel R - Riemann mapping function C - Set of complex numbers - Set of real numbers e, exp - Exponential(e ≈ 2.718...) √ −1 i Im - Imaginary part Re - Real U - Unit disk - Epsilon (small number 0 ≤ < 1) Γ - Curve (boundary of Ω) Γ0 - Outer boundary of a doubly connected region Γ1 - Inner boundary of a doubly connected region π - Pi (π ≈ 3.142...) Ω - Connected region ∈ - Component Sum Integration xviii LIST OF APPENDICES APPENDIX NO. TITLE PAGE A Publications/Presentations 139 B Sample of Computer Programs 143