TABLE OF CONTWNTS

TABLE OF CONTWNTS

ACKNOWLEDGEMENTS...i

ABSTRACT...ii

TABLE OF CONTENTS...iii

LIST OF TABLES...v

LIST OF FIGURES...vi

LIST OF ABBREVIATIONS... viii

INTRODUCTION...1

CHAPTER ONE: LITERATURE REVIEW 1.1 Overview...3

1.2 Literature Background...3

1.3 Forensic History Timeline...3

1.4 Forensic Dentistry...6

1.5 Dental Radiograph...8

1.6 Summary...9

CHAPTER TWO: NEURAL NETWORK 2.1 Overview...10

2.2 Artificial Neural Networks...10

2.3 Human Brain...12

2.4 Neural Network Components ...14

2.5 Models of Neurons...14

2.5.1 Types if Activation Function ...15

2.6 Neural Network Architectures ...18

2.6.1. Single Layer Perceptron...18

2.6.2 Multi Layer Perceptron ...19

2.6.3. Recurrent Networks ...20

2.7 Artificial Neural Network Learning...21

2.7.1 Learning Paradigms...21

2.7.1.1. Supervised Learning...22

2.7.1.2. Unsupervised Learning (Self Organization Learning)...22

2.7.2. Learning Rule...22

2.8 Advantages of Artificial Neural Networks...24

2.9 Back Propagation Algorithm ...25

2.9.1 Feed Forward Network Stage...27

2.9.2 Error Signal...28

2.9.3 Mean Squared Error Function...29

2.9.4 Learning Rate and Momentum Factor...29

2.9.5 Weight Adjusting...29

2.9.6 Back Propagation Training...30

2.10 Summary...32

CHAPTER THREE: DENTAL IDENTIFICATION SYSTEM 3.1 Overview...33

3.2 Dental Identification System Operations...33

3.2.1 Database Collecting...34

3.2.2 Preprocessing...35

3.2.2.1 Image Normalization...35

3.2.2.2 Image Compression ...36

III

3.2.2.3 Image Reading...39

3.2.2.4 Image Vectorization...40

3.3 Using Matlab...40

3.4 Implementation of Neural Network...40

3.4.1 Define Back Propagation Architecture and Parameters...41

3.4.2 Formulation of Weight Adjustment...41

3.4.3 Define the Learning Rate and Momentum Factor...41

3.4.4 Define the Maximum Error...41

3.5 Training Using Back Propagation...42

3.6 Testing the Dental Identification System...48

3.7 Summary...49

CHAPTER FOUR EXPERIMENTAL RESULTS AND COMPARISON 4.1 Overview...50

4.2 General Experimental Setup...50

4.3 First Experiment...50

4.3.1 First Quarter First Experiment ...50

4.3.2 Second Quarter First Experiment ...52

4.3.3 Third Quarter First Experiment ...54

4.3.4 Fourth Quarter First Experiment ...56

4.4 Second Experiment...59

4.4.1 First Quarter Second Experiment ...59

4.4.2 Second Quarter Second Experiment ...61

4.4.3 Third Quarter Second Experiment ...63

4.4.4 Fourth Quarter Second Experiment ...65

4.5 Extra Testing Experiment...67

4.6 Discussion...68

4.7 Summary...70

CONCLUSION AND FUTURE RESEARCH...71

REFERENCES...72

APPENDIX I DATABASE ...75

APPENDIX II EXPERIMENT RESULTS...80

APPENDIX III MATLAB SOURSE CODE...100

IV