7.4 K-Means: A Simple Clustering Method ................................ 131
7.5
Bayesian Classifier ................................................................. 134
7.5.1 Loss Function ........................................................... 136
7.6 Maximum Likelihood Method .............................................. 138
7.7 Neural Networks.................................................................... 140
7.7.1 Perceptron ................................................................. 140
7.7.2 Sigmoid Neural Networks ........................................ 145
7.7.2.1 Activation Function .................................. 146
7.7.2.2 Backpropagation Algorithm ..................... 147
7.7.2.3 Momentum................................................ 148
7.7.3 MATLAB ® for Neural Networks ............................. 149
7.8 Summary ............................................................................... 150
Problems........................................................................................... 150
Reference.......................................................................................... 152
PART II Processing of Biomedical Signals
Chapter 8 Electric Activities of the Cell ........................................................... 155
8.1 Introduction and Overview.................................................... 155
8.2 Ion Transport in Biological Cells .......................................... 155
8.2.1 Transmembrane Potential ......................................... 156
8.3 Electric Characteristics of Cell Membrane ........................... 160
8.3.1 Membrane Resistance .............................................. 160
8.3.2 Membrane Capacitance ............................................ 160
8.3.3 Cell Membrane’s Equivalent Electric Circuit........... 161
8.3.4 Action Potential ........................................................ 161
8.4 Hodgkin–Huxley Model ........................................................ 164
8.5 Electric Data Acquisition ...................................................... 166
8.5.1 Propagation of Electric Potential as a Wave ............ 167
8.6 Some Practical Considerations on Biomedical Electrodes .... 168
8.7 Summary ............................................................................... 169
Problems........................................................................................... 169
Chapter 9 Electrocardiogram ............................................................................ 171
9.1 Introduction and Overview.................................................... 171
9.2 Function and Structure of the Heart ...................................... 171
9.2.1 Cardiac Muscle......................................................... 173
9.2.2 Cardiac Excitation Process ....................................... 174
9.3 Electrocardiogram: Signal of Cardiovascular System .......... 176
9.3.1 Origin of ECG .......................................................... 176
9.3.2 ECG Electrode Placement........................................ 178
9.3.3 Modeling and Representation of ECG ..................... 180
9.3.4 Periodicity of ECG: Heart Rate ............................... 181
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Contents
7.5
Bayesian Classifier ................................................................. 134
7.5.1 Loss Function ........................................................... 136
7.6 Maximum Likelihood Method .............................................. 138
7.7 Neural Networks.................................................................... 140
7.7.1 Perceptron ................................................................. 140
7.7.2 Sigmoid Neural Networks ........................................ 145
7.7.2.1 Activation Function .................................. 146
7.7.2.2 Backpropagation Algorithm ..................... 147
7.7.2.3 Momentum................................................ 148
7.7.3 MATLAB ® for Neural Networks ............................. 149
7.8 Summary ............................................................................... 150
Problems........................................................................................... 150
Reference.......................................................................................... 152
PART II Processing of Biomedical Signals
Chapter 8 Electric Activities of the Cell ........................................................... 155
8.1 Introduction and Overview.................................................... 155
8.2 Ion Transport in Biological Cells .......................................... 155
8.2.1 Transmembrane Potential ......................................... 156
8.3 Electric Characteristics of Cell Membrane ........................... 160
8.3.1 Membrane Resistance .............................................. 160
8.3.2 Membrane Capacitance ............................................ 160
8.3.3 Cell Membrane’s Equivalent Electric Circuit........... 161
8.3.4 Action Potential ........................................................ 161
8.4 Hodgkin–Huxley Model ........................................................ 164
8.5 Electric Data Acquisition ...................................................... 166
8.5.1 Propagation of Electric Potential as a Wave ............ 167
8.6 Some Practical Considerations on Biomedical Electrodes .... 168
8.7 Summary ............................................................................... 169
Problems........................................................................................... 169
Chapter 9 Electrocardiogram ............................................................................ 171
9.1 Introduction and Overview.................................................... 171
9.2 Function and Structure of the Heart ...................................... 171
9.2.1 Cardiac Muscle......................................................... 173
9.2.2 Cardiac Excitation Process ....................................... 174
9.3 Electrocardiogram: Signal of Cardiovascular System .......... 176
9.3.1 Origin of ECG .......................................................... 176
9.3.2 ECG Electrode Placement........................................ 178
9.3.3 Modeling and Representation of ECG ..................... 180
9.3.4 Periodicity of ECG: Heart Rate ............................... 181
x
Contents