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MEDICAL INSTRUMENT DESIGN AND DEVELOPMENT: from Requirements to Market Placements |
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Contents |
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Foreword |
17 |
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Preface |
19 |
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Acknowledgment |
23 |
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1 System Engineering |
25 |
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Chapter Organization |
25 |
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Part I: Theory |
28 |
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1.1 Introduction |
28 |
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1.2 Problem Formulation in Product Design |
28 |
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1.3 The Business Context for Design |
30 |
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1.4 The Engineering Product Design Process |
34 |
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1.5 System-subsystem Decomposition |
39 |
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1.6 The Product Development Life Cycle |
45 |
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1.7 Project Management in Product Design |
48 |
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1.8 Intellectual Property Rights and Reuse |
54 |
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Part II: Implementation |
56 |
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1.11 The ECG: Introduction |
56 |
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1.11.1 The ECG’s diagnostic relevance |
56 |
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1.11.2 ECG Types |
57 |
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1.12 The ECG Design Problem Formulation |
58 |
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1.13 The ECG Business Plan |
60 |
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1.13.1 Market Size and Trend |
61 |
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1.13.2 Core and Distinctive Features |
62 |
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1.14 The ECG Design Process |
64 |
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1.14.1 Transverse Activities of the ECG Design Process |
67 |
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1.14.2 Core Activities of the ECG Design Process |
68 |
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1.15 ECG System–subsystem Decomposition |
68 |
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1.15.1 Hardware Platform Decomposition |
69 |
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1.15.2 Software Application Decomposition |
69 |
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1.16 ECG Product Life Cycle |
70 |
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1.16.1 Overcoming Risk of Inadequate Visualization of ECG Signal |
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1.16.2 Overcoming Risk of Error Fixing in System Integration |
74 |
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1.16.3 Overcoming Risks for Non-stable/Unfeasible Requirements |
74 |
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1.17 The ECG Development Plan and Project Management |
75 |
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1.18 IPR and Reuse Strategy for the ECG |
79 |
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References |
81 |
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2 Concepts and Requirements |
83 |
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Chapter Organization |
83 |
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Part I: Theory |
85 |
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2.1 Introduction |
85 |
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2.2 The Medical Instrumentation Approach |
86 |
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2.3 Extraction of Physiological Parameters |
91 |
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2.4 Pressure and Flow |
94 |
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2.4.1 Blood Pressure |
96 |
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2.4.2 Blood Flow and Hemodynamics |
98 |
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2.5 Biopotential Recording |
103 |
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2.6 Electroencephalography |
105 |
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2.7 Electromyography |
109 |
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Part II: Implementation |
112 |
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2.8 Introduction |
112 |
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2.9 Requirements Management |
113 |
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2.10 Medical Instruments Requirements and Standards |
115 |
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2.11 ECG Requirements |
118 |
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2.12 The Patient Component |
120 |
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2.12.1 The Heart’s Pumping Function and the Circulatory System |
120 |
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2.12.2 Heart Conduction ‘Control’ System |
121 |
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2.13 The ECG Method for Observation |
123 |
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2.13.1 Recording the Heart’s Electrical Signals |
123 |
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2.13.2 ECG Definition and History |
127 |
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2.13.3 ECG Standard Method of Observation |
127 |
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2.14 Features of the Observations |
132 |
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2.14.1 ECG Signal |
132 |
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2.14.2 Clinically Significant Signal |
134 |
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2.14.3 Power Line Noise |
141 |
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2.14.4 Isoelectric Line Instability |
142 |
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2.14.5 Muscle Artifacts |
143 |
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2.15 Requirements Related to Measurements |
143 |
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2.16 Safety Requirements |
150 |
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2.16.1 EMC Performance |
152 |
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2.17 Usability and Marketing Requirements |
155 |
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2.18 Environment Issues |
156 |
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2.19 Economic Requirements |
158 |
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References |
159 |
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3 Biomedical Engineering Design |
161 |
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Chapter Organization |
162 |
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Part I: Theory |
163 |
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3.1 Design Principles and Regulations |
163 |
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3.2 General Design System Model |
165 |
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3.3 Pressure and Flow Instruments |
166 |
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3.3.1 Blood Pressure Instruments |
168 |
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3.3.2 Flow Measurements |
170 |
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3.3.3 Measuring Oxygen Concentration |
171 |
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3.4 Biopotential Instruments |
172 |
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3.4.1 Electroencephalographs |
172 |
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3.4.2 Electromyographs |
175 |
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3.5 The Design Process |
176 |
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3.5.1 The Conceptual Design |
179 |
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3.5.2 System-wide Design Decisions |
180 |
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3.5.3 System Architectural Design |
181 |
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3.5.4 Risk Management |
181 |
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Part II: Implementation |
184 |
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3.6 ECG-wide Decisions |
184 |
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3.6.1 The Gamma Cardio CG Use Case |
184 |
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3.6.2 Human Factors and the User Interface Design |
185 |
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3.6.3 Patient Interface: the Biopotential Electrodes |
191 |
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3.7 The ECG System Architectural Design |
194 |
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3.7.1 Subsystem Identification |
194 |
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3.7.2 The Communication Interfaces |
195 |
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3.7.3 Acquisition Hardware Requirements |
198 |
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3.7.4 Firmware Requirements |
200 |
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3.7.5 Software Application Requirements |
201 |
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3.7.6 Concept of Execution among Subsystems |
202 |
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3.8 Gamma Cardio CG Technical File Structure |
203 |
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References |
204 |
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4 Signal Processing and Estimation |
205 |
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Chapter Organization |
205 |
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Part I: Theory |
208 |
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4.1 Discrete Representations of Analog Systems |
208 |
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4.2 Discrete Fourier Transform |
213 |
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4.2.1 Discrete Fourier Transform Statistics |
218 |
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4.3 Estimation Theory Framework |
221 |
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4.3.1 Minimum Mean Square Error Estimate |
223 |
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4.3.2 Minimum Mean Absolute Error Estimate (MMAE) |
225 |
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4.3.3 Maximum A Posteriori (MAP) Probability Estimate |
226 |
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4.3.4 Maximum Likelihood Estimation (MLE) |
227 |
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4.4 Performance Indicators |
228 |
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4.4.1 Efficient Estimators |
232 |
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4.4.2 Fisher’s Information Matrix |
233 |
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4.4.3 Akaike Information Criterion |
236 |
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Part II: Implementation |
238 |
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4.5 Analog to Digital Conversion |
238 |
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4.5.1 Indirect Sampling versus Direct Sampling |
238 |
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4.5.2 Quantizer Design |
240 |
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4.6 Signal Denoising |
245 |
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4.6.1 White Gaussian Signals in Additive White Gaussian Noise |
245 |
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4.6.2 Denoising of Gaussian Cyclostationary Signals |
246 |
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4.6.3 MMSE Digital Filter |
246 |
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4.7 Time of Arrival Estimation |
248 |
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References |
253 |
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5 Applied Electronics |
255 |
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Chapter Organization |
255 |
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Part I: Theory |
257 |
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5.0 Architectural Design |
259 |
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5.1 Sensors |
260 |
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5.2 Circuit Protection Function |
267 |
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5.2.1 Johnson Noise |
270 |
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5.2.2 Transient Voltage Suppressors |
271 |
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5.2.3 RF Filter Circuit Protection |
272 |
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5.2.4 Circuit Frequency Response |
275 |
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5.3 Buffer Stage |
278 |
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5.3.1 Operational Amplifiers |
280 |
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5.4 Analog Signal Processing |
282 |
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5.4.1 Summing Amplifier Circuit |
283 |
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5.4.2 Analog Signal Switching |
284 |
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5.5 Interference and Instrumentation Amplifiers |
286 |
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5.5.1 Eliminating In-band Interference |
286 |
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5.5.2 Patient Model |
291 |
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5.5.3 The ECG Model |
292 |
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5.5.4 Right Leg Connection |
294 |
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5.5.5 Right Leg Driver Circuit |
296 |
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5.6 Analog Filtering |
297 |
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5.6.1 Frequency Domain |
297 |
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5.6.2 Analog versus Digital Filtering |
302 |
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5.7 ADC Conversion |
303 |
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5.8 Programable Devices |
309 |
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5.9 Power Module |
313 |
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5.9.1 Power Sources |
314 |
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5.9.2 Electrical Safety and Appliance Design |
318 |
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5.9.3 Power Module Design |
322 |
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5.10 Baseband Digital Communication |
325 |
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5.10.1 Data Transmission Elements |
326 |
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Part II: Implementation |
337 |
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5.20 Gamma Cardio CG Architecture |
337 |
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5.20.1 ECG Design Choices |
338 |
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5.20.2 Gamma Cardio CG Complete Scheme |
341 |
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5.21 ECG Sensors |
341 |
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5.22 Gamma Cardio CG Protection |
345 |
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5.23 Gamma Cardio CG Buffer Stage |
349 |
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5.24 The Lead Selector |
351 |
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5.24.1 Calibration |
355 |
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5.25 ECG Amplification |
356 |
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5.25.1 ECG Circuits |
357 |
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5.25.2 Input Dynamic Range: Requirement Demonstrations |
361 |
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5.25.3 Gain Error: Requirement Demonstrations |
362 |
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5.26 Analog Filtering |
363 |
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5.27 The ADC Circuit |
366 |
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5.28 Programable Devices |
370 |
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5.28.1 Circuit Design |
371 |
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5.28.2 The Clock |
372 |
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5.29 Power Module |
375 |
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5.29.1 Power Module Circuit |
377 |
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5.30 Communication Module |
377 |
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Conclusion |
381 |
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References |
382 |
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6 Medical Software |
383 |
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Chapter Organization |
383 |
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Part I: Theory |
385 |
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6.1 Introduction |
385 |
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6.1.1 Intrinsic Risks and Software Engineering |
386 |
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6.1.2 Main Concepts in Software Development |
387 |
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6.1.3 Regulatory Requirements for Software |
388 |
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6.2 The Process: a Standard for Medical Software |
389 |
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6.2.1 IEC/EN 62304 Overview |
389 |
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6.2.2 Risk Analysis for Hardware and Software Design |
392 |
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6.2.3 Software Safety Classification |
394 |
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6.2.4 System Decomposition and Risks |
395 |
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6.2.5 Impact of Safety Classification |
396 |
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6.2.6 SOUP |
396 |
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6.3 Risk Management Process |
398 |
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6.3.1 Risk Management in Software |
400 |
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6.3.2 Risk Management for Medical Instrument Software |
401 |
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6.4 Software Development Process |
403 |
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6.4.1 Software Development Planning |
404 |
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6.4.2 Software Requirements Analysis |
405 |
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6.4.3 Software Architectural Design |
406 |
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6.4.4 Detailed Software Design |
409 |
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6.4.5 Software Unit Implementation and Verification |
409 |
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6.4.6 Software Integration and Integration Testing |
411 |
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6.4.7 Software System Testing |
412 |
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6.4.8 Software Release |
412 |
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6.5 Software Configuration Management Process |
413 |
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6.6 Software Problem Resolution Process |
415 |
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6.7 Software Maintenance Process |
416 |
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6.8 Guidelines on Software Design |
417 |
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6.8.1 Definitions |
419 |
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6.8.2 Basic Recommendations |
420 |
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6.8.3 Software Core Services |
420 |
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6.8.4 Defensive Programing |
422 |
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Part II: Implementation |
424 |
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6.9 System Decomposition |
424 |
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6.9.1 Gamma Cardio CG Use Case |
424 |
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6.9.2 System Decomposition |
425 |
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6.10 Risk Management |
426 |
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6.11 Software Application |
427 |
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6.11.1 Software Requirements |
427 |
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6.11.2 Architectural Design |
431 |
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6.11.3 Elaboration Module |
433 |
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6.12 Firmware |
435 |
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6.12.1 Firmware Requirements |
435 |
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6.12.2 Architectural Design |
437 |
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6.12.3 Automatic Test Capability |
440 |
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References |
442 |
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7 c-Health |
443 |
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Chapter Organization |
444 |
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Part I: Theory |
445 |
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7.1 Introduction |
445 |
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7.1.1 The Assessment Framework |
445 |
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7.1.2 Assessment Framework for the Health Sector |
446 |
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7.2 The Cloud Computing Model |
450 |
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7.2.1 Basics of Cloud Computing |
450 |
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7.2.2 Cloud Platforms |
452 |
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7.2.3 Services in the Cloud |
454 |
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7.2.4 The Cloud Shape |
456 |
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7.2.5 Features of the Clouds |
458 |
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7.3 e-Health |
459 |
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7.3.1 Interoperability in e-Health |
461 |
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7.4 Electronic Health Record (EHR) |
466 |
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7.5 c-Health |
469 |
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Part II: Implementation |
473 |
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7.6 Telecardiology |
474 |
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7.6.1 Application Scenario |
474 |
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7.7 Telecardiology Technology |
475 |
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7.8 Workflow in Telecardiology |
479 |
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7.8.1 Basic Workflows |
479 |
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7.8.2 Alternative Workflows |
481 |
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7.8.3 Where and When Telecardiology Can Be Used |
484 |
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7.9 Risks of Telecardiology |
487 |
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References |
489 |
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8 Certification Process |
491 |
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Chapter Organization |
491 |
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Part I: Theory |
493 |
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8.1 Certification Objectives and Processes |
493 |
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8.1.1 Certification, Standards and Definitions |
494 |
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8.2 Regulations, Standards and Organizations |
498 |
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8.2.1 Technical Standards for Medical Devices |
501 |
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8.2.2 European Context |
502 |
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8.3 Basic Protection Concepts |
504 |
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8.3.1 Protection Against Electric Shock |
504 |
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8.3.2 Insulation |
508 |
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8.3.3 Degree of Protection Provided by Enclosures |
509 |
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8.4 Verification of Constructional Requirements |
510 |
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8.4.1 Choice of Safety Critical Materials and Components |
510 |
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8.4.2 Creepage Distances and Air Clearances |
513 |
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8.4.3 Markings |
514 |
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8.4.4 Conductors |
516 |
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8.4.5 Connections to the Power Supply |
518 |
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8.4.6 Fire Enclosure |
519 |
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8.5 Medical Equipment Safety Tests |
519 |
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8.5.1 Leakage Current |
521 |
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8.5.2 Heating |
523 |
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8.5.3 Dielectric Strength |
524 |
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8.5.4 Stability and Mechanical Strength |
524 |
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8.5.5 Abnormal Operating and Fault Conditions |
525 |
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8.5.6 Continuity of Protective Earthing |
526 |
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8.5.7 Residual Voltage |
527 |
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8.5.8 Voltage on the Accessible Parts |
527 |
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8.5.9 Energy Stored – Pressurized Part |
527 |
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8.5.10 Current and Power Consumption |
528 |
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8.6 Electromagnetic Compatibility |
528 |
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8.6.1 Emissions |
530 |
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8.6.2 Immunity |
535 |
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8.6.3 The Test Report |
537 |
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Part II: Implementation |
539 |
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8.11 The Process |
539 |
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8.11.1 Device Description |
540 |
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8.11.2 Medical Device Classes |
540 |
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8.11.3 EU Conformity Assessment |
543 |
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8.11.4 Risk Management Deliverable |
544 |
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8.11.5 The Technical File |
551 |
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8.12 Regulatory Approaches to Medical Device Market Placement |
561 |
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8.13 Basic Concepts in Device Implementation |
564 |
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8.13.1 Protection Against Electric Shock |
565 |
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8.13.2 Insulation |
565 |
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8.13.3 Enclosure IP Protection |
568 |
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8.14 Verification on Design Performance |
568 |
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8.14.1 Safety-critical Materials |
568 |
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8.14.2 Creepage and Air Clearance |
569 |
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8.14.3 Other Verifications |
569 |
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8.15 Safety Tests |
570 |
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8.15.1 Leakage Current |
570 |
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8.15.2 Heating |
570 |
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8.15.3 Other Safety Tests |
571 |
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8.16 Electromagnetic Compatibility |
572 |
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8.16.1 Emission |
573 |
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8.16.2 Immunity |
574 |
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References |
578 |
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Summary of Regulations and Standards |
579 |
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Index |
583 |
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