E1FTOC 09/15/2010
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7 Sampling, Digital Devices, and Data Acquisition
260
7.1
Introduction
260
7.2
Sampling Concepts
261
7.3
Digital Devices: Bits and Words
269
7.4
Transmitting Digital Numbers: High and Low Signals
271
7.5
Voltage Measurements
271
7.6
Data-Acquisition Systems
283
7.7
Data-Acquisition System Components
284
7.8
Analog Input-Output Communication
288
7.9
Digital Input-Output Communication
293
7.10 Digital Image Acquisition and Processing
299
7.11 Summary
303
References
303
Suggested Reading
304
Nomenclature
304
Problems
305
8 Temperature Measurements
309
8.1
Introduction
309
8.2
Temperature Standards and Definition
310
8.3
Thermometry Based on Thermal Expansion
313
8.4
Electrical Resistance Thermometry
315
8.5
Thermoelectric Temperature Measurement
330
8.6
Radiative Temperature Measurements
351
8.7
Physical Errors in Temperature Measurement
356
8.8
Summary
365
References
365
Nomenclature
366
Problems
367
9 Pressure and Velocity Measurements
375
9.1
Introduction
375
9.2
Pressure Concepts
375
9.3
Pressure Reference Instruments
378
9.4
Pressure Transducers
386
9.5
Pressure Transducer Calibration
392
9.6
Pressure Measurements in Moving Fluids
396
9.7
Modeling Pressure and Fluid Systems
400
9.8
Design and Installation: Transmission Effects
401
9.9
Fluid Velocity Measuring Systems
405
9.10 Summary
415
References
416
Nomenclature
417
Problems
417
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