Mechanics of Impression EvidencePDF电子书下载

1 Forensic Analysis of Wood DNA&SANDRA L. WILSON AND DAVID S. PIERCE 1

1.1 Introduction 1

1.2 Materials, Methods, and Results 2

1.3 Discussion 3

Acknowledgments 5

References 5

2 Signs of Evolution 7

2.1 A New Beginning for Forensics 7

2.1.1 Forensic Evolution 7

2.1.2 Effects of Scientific Evolution 8

2.2 Substrate to Structure 9

2.3 Forces 11

2.3.1 Forces Big and Small 11

2.3.2 Plainly Small Forces 13

2.4 A Basic Look at a Popular Substrate 14

2.4.1 Polymers 14

2.4.2 Primary and Secondary Bonds 14

2.4.3 Manufacture and Growth of Polymers 15

2.4.4 Natural Polymers and New Products 17

2.4.5 Polymer Strength and Deformation 18

2.4.6 Hysteresis 19

2.4.7 Elastic Limit and Deformation 20

2.4.8 Furthering an Understanding of Polymer Deformation 21

2.4.9 Solubility 22

2.5 Symmetry 24

2.5.1 Symmetry by Design or Circumstance 24

2.5.2 Natural Symmetry 25

2.5.3 The Structure of a Digit 26

2.6 Perspective 29

2.6.1 Offering a Different View 29

2.6.2 Approaching a Different View 29

References 30

3 Ivory Tower Syndrome 33

3.1 The View Has Changed 33

3.1.1 The Making of Towers 33

3.1.2 Descending a Tower 35

3.1.3 The View at Ground Level 37

3.2 The Basis 39

3.2.1 An Ability to Perceive 40

3.2.2 The Ability to Describe Basic Properties of a Material 41

3.2.3 The Changing Basis that Begins with Reason 44

3.2.4 The Identification Process 46

3.2.5 Developing a Physical Basis 49

3.2.6 The Relevance of a Physical Basis 50

References 54

4 The Ground We Walk On 55

4.1 Soil Composition 55

4.2 The Structure of Soil 57

4.3 Influences that Act on Soils 59

4.4 A Curious Destination for Minerals and Dyes 62

References 62

5 Measurement&EUGENE LISCIO AND DAVID S. PIERCE 63

5.1 The Relevance of Measurement 63

5.1.1 Introduction 63

5.1.2 Measurement and Counting 63

5.1.3 Thresholds and Proportion 64

5.1.4 Measuring Equipment 64

5.1.5 Precision and Accuracy of Measurement 66

5.1.6 Introducing a New Scale 67

5.2 Accuracy and Language Issues 71

5.2.1 Introduction 71

5.2.2 Measuring Waves 72

5.3 Photogrammetry 74

5.3.1 Applications 74

5.3.2 Image Size and Measurement 77

5.3.3 Camera Distortions 78

5.4 Stereoscopic Images and Scanning Synopsis 79

References 81

6 Fluids&PATRICK MALLAY AND DAVID S. PIERCE 83

6.1 Simple Drops 84

6.1.1 Apparatus 84

6.1.2 Procedure 84

6.1.3 Observations 84

6.1.4 Spattered Drops 86

6.2 Modeling Droplets 87

6.2.1 Mathematical Model for the Volume of Liquid Droplets 87

6.2.2 Velocity of Liquid Droplets in Air 87

6.3 Sample Calculation 88

6.4 Experimental Process 90

6.4.1 Apparatus 90

6.4.2 Procedures 90

6.4.2.1 Determining the Surface Tension and Density of Test Liquids 90

6.4.2.2 Determining the Drop Height 92

6.4.2.3 Performing the Drop 92

6.5 Friction and Fluids 94

6.5.1 Apparatus 95

6.5.2 Procedure for Determining Effect of Liquids on Friction 95

6.5.2.1 Observations 95

6.5.2.2 Discussion 97

6.5.3 Rubber Friction 97

6.5.4 Matters Involving Blood 98

6.6 Analysis and Comparison 98

6.6.1 The Value of Droplet Studies to Analysis and Comparison 98

6.6.2 Capillarity 100

6.6.3 Rough Surfaces 103

6.7 Summary 104

References 105

7 Surface Pairings 107

7.1 The Value of a Surface Pairing 107

7.1.1 Hypothesis 107

7.1.2 Definitions and Concepts 108

7.1.3 Properties of Common Substrates 111

7.1.4 Properties of the Common Matrix 111

7.1.5 Synergistic Effects 113

7.1.6 Expectations (and Distortions) 113

7.1.7 Another Challenge 114

7.2 Sequential Analysis 115

7.2.1 Understanding the Sequence 115

7.2.2 Effects of Pressure on Sequential Analysis 118

7.2.3 Equipment 118

7.2.4 Methodology 119

7.2.5 Discussion 119

7.2.6 Creep 120

7.3 Transfer 121

7.3.1 Direct and Anecdotal Transfers 121

7.3.2 Deformed Transfer 122

7.3.3 Schallamach Patterning 122

7.3.4 Intaglio 123

7.4 Coincidental Impressions 124

7.5 Paired Surfaces at a Point of Contact 126

7.6 Industrial Materials 126

7.6.1 Common Attributes of Manufactured Products 126

7.6.2 Interactions at Interfaces of Industrial Materials 128

7.6.3 Causes of Change to Substances 129

7.6.4 Dimensional Stability Issues 130

7.6.5 The Importance of Friction 130

References 131

8 Bias 133

8.1 Sources of Bias 133

8.2 Creation Theory Bias 135

8.3 The Awful Truth about Bias 135

8.4 Errors 137

8.5 Validation 137

8.6 Confirmation 140

References 140

9 Exhibits to Evidence 141

9.1 Re-Creating the Scene 141

9.1.1 Considering Observations 141

9.1.2 Preconceptions 142

9.1.3 Condition Theories 144

9.1.4 Creation Theories 145

9.1.5 A Closer Look at the Role of Observations and Theories in an Analysis 147

9.1.6 Comparison 149

9.1.7 Cost Factor 150

9.1.8 Conclusions 151

9.2 The Use of Observations 152

9.2.1 Transforming Observations into Opinion Evidence 152

9.2.2 Merging Technology and Practice 155

9.2.3 Limitations of Current Practice 156

9.2.4 Expanding the Scope 157

9.2.5 Reduction Techniques 157

References 159

10 Validation Study of Three-Dimensional Striations from Outsoles 161

10.1 Beginning with Markings 161

10.1.1 Striation Marks 161

10.1.2 Experiment to Define Striation Repeatability 161

10.1.3 Equipment 161

10.1.4 Methodology 162

10.1.5 Discussion 162

10.1.6 Edge Characteristics of Footwear 164

10.1.7 Improvement of Test Equipment 165

10.1.8 Choice of Substrate 168

10.2 The Hypothesis 170

10.2.1 Methods of Testing the Hypothesis 170

10.2.2 Designing the Test Conditions 171

10.3 Empirical Studies 171

10.3.1 A Study of Angles 171

10.3.2 Methodology 172

10.3.3 Discussion 175

10.4 Dimensional Stability of Outsoles 178

10.4.1 Complications Introduced by Dimensional Stability 178

10.4.2 Equipment 178

10.4.3 Method 178

10.4.4 Tables of Averaged Values 180

10.4.5 Discussion 182

10.5 Experiments with Casual Exposures to Solvents 183

10.5.1 Periodic Exposure to Solvents 183

10.5.1.1 Equipment 183

10.5.1.2 Method 183

10.5.1.3 Discussion 183

10.5.1.4 Conclusion 183

10.5.2 Casual Exposure Measured by Weight 183

10.5.2.1 Equipment 184

10.5.2.2 Method 184

10.5.2.3 Results 184

10.5.2.4 Discussion 184

10.6 Summary of Possibilities and Probabilities of Validation 184

References 186

11 Potential of Electrostatics 187

11.1 Images of Electrons 187

11.1.1 The Potential of Electrostatic Technology 187

11.1.2 How It Works 187

11.1.3 Why It Is Not Evidence 189

11.1.4 Potential Applications: Why Bother? 190

11.1.5 The Triboelectric Series 191

References 196

12 Toward Development of a Unified Theory 197

12.1 Collective Value 197

12.1.1 Formation of a Theory 197

12.1.2 Diagnostics 197

12.1.3 Scope 199

12.1.4 Suggesting a Design Path 200

12.1.5 Modeling Techniques 201

12.2 Cautions 204

References 204

Appendix: Terminal Velocity Calculator 205

Index 209