电路基础（英文版·第5版）
PART 1 DC Circuits 2
Chapter 1 Basic Concepts 3
1.1 Introduction 4
1.2 Systems of Units 5
1.3 Charge and Current 5
1.4 Voltage 9
1.5 Power and Energy 10
1.6 Circuit Elements 15
1.7 Applications 17
1.7.1 TV Picture Tube
1.7.2 Electricity Bills
1.8 Problem Solving 20
1.9 Summary 23
Review Questions 24
Problems 24
Comprehensive Problems 27
Chapter 2 Basic Laws 29
2.1 Introduction 30
2.2 Ohm’s Law 30
2.3 Nodes, Branches, and Loops 35
2.4 Kirchhoff’s Laws 37
2.5 Series Resistors and Voltage Division 43
2.6 Parallel Resistors and Current Division 45
2.7 Wye-Delta Transformations 52 Delta to Wye Conversion Wye to Delta Conversion
2.8 Applications 58
2.8.1 Lighting Systems
2.8.2 Design of DC Meters
2.9 Summary 64 Review Questions 66 Problems 67 Comprehensive Problems 78
Chapter 3 Methods of Analysis 81
3.1 Introduction 82
3.2 Nodal Analysis 82
3.3 Nodal Analysis with Voltage Sources 88
3.4 Mesh Analysis 93
3.5 Mesh Analysis with Current Sources 98
3.6 Nodal and Mesh Analyses by Inspection 100
3.7 Nodal Versus Mesh Analysis 104
3.8 Circuit Analysis with PSpice 105
3.9 Applications: DC Transistor Circuits 107
3.10 Summary 112
Review Questions 113
Problems 114
Comprehensive Problem 126
Chapter 4 Circuit Theorems 127
4.1 Introduction 128
4.2 Linearity Property 128
4.3 Superposition 130
4.4 Source Transformation 135
4.5 Thevenin’s Theorem 139
4.6 Norton’s Theorem 145
4.7 Derivations of Thevenin’s and Norton’s Theorems 149
4.8 Maximum Power Transfer 150
4.9 Verifying Circuit Theorems with PSpice 152
4.10 Applications 155
4.10.1 Source Modeling
4.10.2 Resistance Measurement
4.11 Summary 160
Review Questions 161
Problems 162
Comprehensive Problems 173
Chapter 5 Operational Ampli ers 175
5.1 Introduction 176
5.2 Operational Ampli ers 176
5.3 Ideal Op Amp 179
5.4 Inverting Ampli er 181
5.5 Noninverting Ampli er 183
5.6 Summing Ampli er 185
5.7 Difference Ampli er 187
5.8 Cascaded Op Amp Circuits 191
5.9 Op Amp Circuit Analysis with PSpice 194
5.10 Applications 196
5.10.1 Digital-to-Analog Converter
5.10.2 Instrumentation Ampli ers
5.11 Summary 199
Review Questions 201
Problems 202
Comprehensive Problems 213
Chapter 6 Capacitors and Inductors 215
6.1 Introduction 216
6.2 Capacitors 216
6.3 Series and Parallel Capacitors 222
6.4 Inductors 226
6.5 Series and Parallel Inductors 230
6.6 Applications 233
6.6.1 Integrator
6.6.2 Differentiator
6.6.3 Analog Computer
6.7 Summary 240
Review Questions 241
Problems 242
Comprehensive Problems 251
Chapter 7 First-Order Circuits 253
7.1 Introduction 254
7.2 The Source-Free RC Circuit 254
7.3 The Source-Free RL Circuit 259
7.4 Singularity Functions 265
7.5 Step Response of an RC Circuit 273
7.6 Step Response of an RL Circuit 280
7.7 First-Order Op Amp Circuits 284
7.8 Transient Analysis with PSpice 289
7.9 Applications 293
7.9.1 Delay Circuits
7.9.2 Photo ash Unit
7.9.3 Relay Circuits
7.9.4 Automobile Ignition Circuit
7.10 Summary 299
Review Questions 300
Problems 301
Comprehensive Problems 311
Chapter 8 Second-Order Circuits 313
8.1 Introduction 314
8.2 Finding Initial and Final Values 314
8.3 The Source-Free Series RLC Circuit 319
8.4 The Source-Free Parallel RLC Circuit 326
8.5 Step Response of a Series RLC Circuit 331
8.6 Step Response of a Parallel RLC Circuit 336
8.7 General Second-Order Circuits 339
8.8 Second-Order Op Amp Circuits 344
8.9 PSpice Analysis of RLC Circuits 346
8.10 Duality 350
8.11 Applications 353
8.11.1 Automobile Ignition System
8.11.2 Smoothing Circuits
8.12 Summary 356
Review Questions 357
Problems 358
Comprehensive Problems 367
PART 2 AC Circuits 368
Chapter 9 Sinusoids and Phasors 369
9.1 Introduction 370
9.2 Sinusoids 371
9.3 Phasors 376
9.4 Phasor Relationships for Circuit Elements 385
9.5 Impedance and Admittance 387
9.6 Kirchhoff’s Laws in the Frequency Domain 389
9.7 Impedance Combinations 390
9.8 Applications 396
9.8.1 Phase-Shifters
9.8.2 AC Bridges
9.9 Summary 402
Review Questions 403
Problems 403
Comprehensive Problems 411
Chapter 10 Sinusoidal Steady-State Analysis 413
10.1 Introduction 414
10.2 Nodal Analysis 414
10.3 Mesh Analysis 417
10.4 Superposition Theorem 421
10.5 Source Transformation 424
10.6 Thevenin and Norton Equivalent Circuits 426
10.7 Op Amp AC Circuits 431
10.8 AC Analysis Using PSpice 433
10.9 Applications 437
10.9.1 Capacitance Multiplier
10.9.2 Oscillators
10.10 Summary 441
Review Questions 441
Problems 443
Chapter 11 AC Power Analysis 457
11.1 Introduction 458
11.2 Instantaneous and Average Power 458
11.3 Maximum Average Power Transfer 464
11.4 Effective or RMS Value 467
11.5 Apparent Power and Power Factor 470
11.6 Complex Power 473
11.7 Conservation of AC Power 477
11.8 Power Factor Correction 481
11.9 Applications 483
11.9.1 Power Measurement
11.9.2 Electricity Consumption Cost
11.10 Summary 488
Review Questions 490
Problems 490
Comprehensive Problems 500
Chapter 12 Three-Phase Circuits 503
12.1 Introduction 504
12.2 Balanced Three-Phase Voltages 505
12.3 Balanced Wye-Wye Connection 509
12.4 Balanced Wye-Delta Connection 512
12.5 Balanced Delta-Delta Connection 514
12.6 Balanced Delta-Wye Connection 516
12.7 Power in a Balanced System 519
12.8 Unbalanced Three-Phase Systems 525
12.9 PSpice for Three-Phase Circuits 529
12.10 Applications 534
12.10.1 Three-Phase Power Measurement
12.10.2 Residential Wiring
12.11 Summary 543
Review Questions 543
Problems 544
Comprehensive Problems 553
Chapter 13 Magnetically Coupled Circuits 555
13.1 Introduction 556
13.2 Mutual Inductance 556
13.3 Energy in a Coupled Circuit 564
13.4 Linear Transformers 567
13.5 Ideal Transformers 573
13.6 Ideal Autotransformers 581
13.7 Three-Phase Transformers 584
13.8 PSpice Analysis of Magnetically Coupled Circuits 586
13.9 Applications 591
13.9.1 Transformer as an Isolation Device
13.9.2 Transformer as a Matching Device
13.9.3 Power Distribution
13.10 Summary 597
Review Questions 598
Problems 599
Comprehensive Problems 611
Chapter 14 Frequency Response 613
14.1 Introduction 614
14.2 Transfer Function 614
14.3 The Decibel Scale 617
14.4 Bode Plots 619
14.5 Series Resonance 629
14.6 Parallel Resonance 634
14.7 Passive Filters 637
14.7.1 Lowpass Filter
14.7.2 Highpass Filter
14.7.3 Bandpass Filter
14.7.4 Bandstop Filter
14.8 Active Filters 642
14.8.1 First-Order Lowpass Filter
14.8.2 First-Order Highpass Filter
14.8.3 Bandpass Filter
14.8.4 Bandreject （or Notch） Filter
14.9 Scaling 648
14.9.1 Magnitude Scaling
14.9.2 Frequency Scaling
14.9.3 Magnitude and Frequency Scaling
14.10 Frequency Response Using PSpice 652
14.11 Computation Using MATLAB 655
14.12 Applications 657
14.12.1 Radio Receiver
14.12.2 Touch-Tone Telephone
14.12.3 Crossover Network
14.13 Summary 663
Review Questions 664
Problems 665
Comprehensive Problems 673
PART 3 Advanced Circuit Analysis 674
Chapter 15 Introduction to the LaplaceTransform 675
15.1 Introduction 676
15.2 De nition of the Laplace Transform 677
15.3 Properties of the Laplace Transform 679
15.4 The Inverse Laplace Transform 690
15.4.1 Simple Poles
15.4.2 Repeated Poles
15.4.3 Complex Poles
15.5 The Convolution Integral 697
15.6 Application to Integrodifferential Equations 705
15.7 Summary 708
Review Questions 708
Problems 709
Chapter 16 Applications of the Laplace Transform 715
16.1 Introduction 716
16.2 Circuit Element Models 716
16.3 Circuit Analysis 722
16.4 Transfer Functions 726
16.5 State Variables 730
16.6 Applications 737
16.6.1 Network Stability
16.6.2 Network Synthesis
16.7 Summary 745
Review Questions 746
Problems 747
Comprehensive Problems 758
Chapter 17 The Fourier Series 759
17.1 Introduction 760
17.2 Trigonometric Fourier Series 760
17.3 Symmetry Considerations 768
17.3.1 Even Symmetry
17.3.2 Odd Symmetry
17.3.3 Half-Wave Symmetry
17.4 Circuit Applications 778
17.5 Average Power and RMS Values 782
17.6 Exponential Fourier Series 785
17.7 Fourier Analysis with PSpice 791
17.7.1 Discrete Fourier Transform
17.7.2 Fast Fourier Transform
17.8 Applications 797
17.8.1 Spectrum Analyzers
17.8.2 Filters
17.9 Summary 800
Review Questions 802
Problems 802
Comprehensive Problems 811
Chapter 18 Fourier Transform 813
18.1 Introduction 814
18.2 De nition of the Fourier Transform 814
18.3 Properties of the Fourier Transform 820
18.4 Circuit Applications 833
18.5 Parseval’s Theorem 836
18.6 Comparing the Fourier and Laplace Transforms 839
18.7 Applications 840
18.7.1 Amplitude Modulation
18.7.2 Sampling
18.8 Summary 843
Review Questions 844
Problems 845
Comprehensive Problems 851
Chapter 19 Two-Port Networks 853
19.1 Introduction 854
19.2 Impedance Parameters 854
19.3 Admittance Parameters 859
19.4 Hybrid Parameters 862
19.5 Transmission Parameters 867
19.6 Relationships Between Parameters 872
19.7 Interconnection of Networks 875
19.8 Computing Two-Port Parameters Using PSpice 881
19.9 Applications 884
19.9.1 Transistor Circuits
19.9.2 Ladder Network Synthesis
19.10 Summary 893
Review Questions 894
Problems 894
Comprehensive Problem 905
Appendix A Simultaneous Equations and Matrix
Inversion A
Appendix B Complex Numbers A-9
Appendix C Mathematical Formulas A-16
Appendix D Answers to Odd-Numbered
Problems A-21
Chapter 1 Basic Concepts 3
1.1 Introduction 4
1.2 Systems of Units 5
1.3 Charge and Current 5
1.4 Voltage 9
1.5 Power and Energy 10
1.6 Circuit Elements 15
1.7 Applications 17
1.7.1 TV Picture Tube
1.7.2 Electricity Bills
1.8 Problem Solving 20
1.9 Summary 23
Review Questions 24
Problems 24
Comprehensive Problems 27
Chapter 2 Basic Laws 29
2.1 Introduction 30
2.2 Ohm’s Law 30
2.3 Nodes, Branches, and Loops 35
2.4 Kirchhoff’s Laws 37
2.5 Series Resistors and Voltage Division 43
2.6 Parallel Resistors and Current Division 45
2.7 Wye-Delta Transformations 52 Delta to Wye Conversion Wye to Delta Conversion
2.8 Applications 58
2.8.1 Lighting Systems
2.8.2 Design of DC Meters
2.9 Summary 64 Review Questions 66 Problems 67 Comprehensive Problems 78
Chapter 3 Methods of Analysis 81
3.1 Introduction 82
3.2 Nodal Analysis 82
3.3 Nodal Analysis with Voltage Sources 88
3.4 Mesh Analysis 93
3.5 Mesh Analysis with Current Sources 98
3.6 Nodal and Mesh Analyses by Inspection 100
3.7 Nodal Versus Mesh Analysis 104
3.8 Circuit Analysis with PSpice 105
3.9 Applications: DC Transistor Circuits 107
3.10 Summary 112
Review Questions 113
Problems 114
Comprehensive Problem 126
Chapter 4 Circuit Theorems 127
4.1 Introduction 128
4.2 Linearity Property 128
4.3 Superposition 130
4.4 Source Transformation 135
4.5 Thevenin’s Theorem 139
4.6 Norton’s Theorem 145
4.7 Derivations of Thevenin’s and Norton’s Theorems 149
4.8 Maximum Power Transfer 150
4.9 Verifying Circuit Theorems with PSpice 152
4.10 Applications 155
4.10.1 Source Modeling
4.10.2 Resistance Measurement
4.11 Summary 160
Review Questions 161
Problems 162
Comprehensive Problems 173
Chapter 5 Operational Ampli ers 175
5.1 Introduction 176
5.2 Operational Ampli ers 176
5.3 Ideal Op Amp 179
5.4 Inverting Ampli er 181
5.5 Noninverting Ampli er 183
5.6 Summing Ampli er 185
5.7 Difference Ampli er 187
5.8 Cascaded Op Amp Circuits 191
5.9 Op Amp Circuit Analysis with PSpice 194
5.10 Applications 196
5.10.1 Digital-to-Analog Converter
5.10.2 Instrumentation Ampli ers
5.11 Summary 199
Review Questions 201
Problems 202
Comprehensive Problems 213
Chapter 6 Capacitors and Inductors 215
6.1 Introduction 216
6.2 Capacitors 216
6.3 Series and Parallel Capacitors 222
6.4 Inductors 226
6.5 Series and Parallel Inductors 230
6.6 Applications 233
6.6.1 Integrator
6.6.2 Differentiator
6.6.3 Analog Computer
6.7 Summary 240
Review Questions 241
Problems 242
Comprehensive Problems 251
Chapter 7 First-Order Circuits 253
7.1 Introduction 254
7.2 The Source-Free RC Circuit 254
7.3 The Source-Free RL Circuit 259
7.4 Singularity Functions 265
7.5 Step Response of an RC Circuit 273
7.6 Step Response of an RL Circuit 280
7.7 First-Order Op Amp Circuits 284
7.8 Transient Analysis with PSpice 289
7.9 Applications 293
7.9.1 Delay Circuits
7.9.2 Photo ash Unit
7.9.3 Relay Circuits
7.9.4 Automobile Ignition Circuit
7.10 Summary 299
Review Questions 300
Problems 301
Comprehensive Problems 311
Chapter 8 Second-Order Circuits 313
8.1 Introduction 314
8.2 Finding Initial and Final Values 314
8.3 The Source-Free Series RLC Circuit 319
8.4 The Source-Free Parallel RLC Circuit 326
8.5 Step Response of a Series RLC Circuit 331
8.6 Step Response of a Parallel RLC Circuit 336
8.7 General Second-Order Circuits 339
8.8 Second-Order Op Amp Circuits 344
8.9 PSpice Analysis of RLC Circuits 346
8.10 Duality 350
8.11 Applications 353
8.11.1 Automobile Ignition System
8.11.2 Smoothing Circuits
8.12 Summary 356
Review Questions 357
Problems 358
Comprehensive Problems 367
PART 2 AC Circuits 368
Chapter 9 Sinusoids and Phasors 369
9.1 Introduction 370
9.2 Sinusoids 371
9.3 Phasors 376
9.4 Phasor Relationships for Circuit Elements 385
9.5 Impedance and Admittance 387
9.6 Kirchhoff’s Laws in the Frequency Domain 389
9.7 Impedance Combinations 390
9.8 Applications 396
9.8.1 Phase-Shifters
9.8.2 AC Bridges
9.9 Summary 402
Review Questions 403
Problems 403
Comprehensive Problems 411
Chapter 10 Sinusoidal Steady-State Analysis 413
10.1 Introduction 414
10.2 Nodal Analysis 414
10.3 Mesh Analysis 417
10.4 Superposition Theorem 421
10.5 Source Transformation 424
10.6 Thevenin and Norton Equivalent Circuits 426
10.7 Op Amp AC Circuits 431
10.8 AC Analysis Using PSpice 433
10.9 Applications 437
10.9.1 Capacitance Multiplier
10.9.2 Oscillators
10.10 Summary 441
Review Questions 441
Problems 443
Chapter 11 AC Power Analysis 457
11.1 Introduction 458
11.2 Instantaneous and Average Power 458
11.3 Maximum Average Power Transfer 464
11.4 Effective or RMS Value 467
11.5 Apparent Power and Power Factor 470
11.6 Complex Power 473
11.7 Conservation of AC Power 477
11.8 Power Factor Correction 481
11.9 Applications 483
11.9.1 Power Measurement
11.9.2 Electricity Consumption Cost
11.10 Summary 488
Review Questions 490
Problems 490
Comprehensive Problems 500
Chapter 12 Three-Phase Circuits 503
12.1 Introduction 504
12.2 Balanced Three-Phase Voltages 505
12.3 Balanced Wye-Wye Connection 509
12.4 Balanced Wye-Delta Connection 512
12.5 Balanced Delta-Delta Connection 514
12.6 Balanced Delta-Wye Connection 516
12.7 Power in a Balanced System 519
12.8 Unbalanced Three-Phase Systems 525
12.9 PSpice for Three-Phase Circuits 529
12.10 Applications 534
12.10.1 Three-Phase Power Measurement
12.10.2 Residential Wiring
12.11 Summary 543
Review Questions 543
Problems 544
Comprehensive Problems 553
Chapter 13 Magnetically Coupled Circuits 555
13.1 Introduction 556
13.2 Mutual Inductance 556
13.3 Energy in a Coupled Circuit 564
13.4 Linear Transformers 567
13.5 Ideal Transformers 573
13.6 Ideal Autotransformers 581
13.7 Three-Phase Transformers 584
13.8 PSpice Analysis of Magnetically Coupled Circuits 586
13.9 Applications 591
13.9.1 Transformer as an Isolation Device
13.9.2 Transformer as a Matching Device
13.9.3 Power Distribution
13.10 Summary 597
Review Questions 598
Problems 599
Comprehensive Problems 611
Chapter 14 Frequency Response 613
14.1 Introduction 614
14.2 Transfer Function 614
14.3 The Decibel Scale 617
14.4 Bode Plots 619
14.5 Series Resonance 629
14.6 Parallel Resonance 634
14.7 Passive Filters 637
14.7.1 Lowpass Filter
14.7.2 Highpass Filter
14.7.3 Bandpass Filter
14.7.4 Bandstop Filter
14.8 Active Filters 642
14.8.1 First-Order Lowpass Filter
14.8.2 First-Order Highpass Filter
14.8.3 Bandpass Filter
14.8.4 Bandreject （or Notch） Filter
14.9 Scaling 648
14.9.1 Magnitude Scaling
14.9.2 Frequency Scaling
14.9.3 Magnitude and Frequency Scaling
14.10 Frequency Response Using PSpice 652
14.11 Computation Using MATLAB 655
14.12 Applications 657
14.12.1 Radio Receiver
14.12.2 Touch-Tone Telephone
14.12.3 Crossover Network
14.13 Summary 663
Review Questions 664
Problems 665
Comprehensive Problems 673
PART 3 Advanced Circuit Analysis 674
Chapter 15 Introduction to the LaplaceTransform 675
15.1 Introduction 676
15.2 De nition of the Laplace Transform 677
15.3 Properties of the Laplace Transform 679
15.4 The Inverse Laplace Transform 690
15.4.1 Simple Poles
15.4.2 Repeated Poles
15.4.3 Complex Poles
15.5 The Convolution Integral 697
15.6 Application to Integrodifferential Equations 705
15.7 Summary 708
Review Questions 708
Problems 709
Chapter 16 Applications of the Laplace Transform 715
16.1 Introduction 716
16.2 Circuit Element Models 716
16.3 Circuit Analysis 722
16.4 Transfer Functions 726
16.5 State Variables 730
16.6 Applications 737
16.6.1 Network Stability
16.6.2 Network Synthesis
16.7 Summary 745
Review Questions 746
Problems 747
Comprehensive Problems 758
Chapter 17 The Fourier Series 759
17.1 Introduction 760
17.2 Trigonometric Fourier Series 760
17.3 Symmetry Considerations 768
17.3.1 Even Symmetry
17.3.2 Odd Symmetry
17.3.3 Half-Wave Symmetry
17.4 Circuit Applications 778
17.5 Average Power and RMS Values 782
17.6 Exponential Fourier Series 785
17.7 Fourier Analysis with PSpice 791
17.7.1 Discrete Fourier Transform
17.7.2 Fast Fourier Transform
17.8 Applications 797
17.8.1 Spectrum Analyzers
17.8.2 Filters
17.9 Summary 800
Review Questions 802
Problems 802
Comprehensive Problems 811
Chapter 18 Fourier Transform 813
18.1 Introduction 814
18.2 De nition of the Fourier Transform 814
18.3 Properties of the Fourier Transform 820
18.4 Circuit Applications 833
18.5 Parseval’s Theorem 836
18.6 Comparing the Fourier and Laplace Transforms 839
18.7 Applications 840
18.7.1 Amplitude Modulation
18.7.2 Sampling
18.8 Summary 843
Review Questions 844
Problems 845
Comprehensive Problems 851
Chapter 19 Two-Port Networks 853
19.1 Introduction 854
19.2 Impedance Parameters 854
19.3 Admittance Parameters 859
19.4 Hybrid Parameters 862
19.5 Transmission Parameters 867
19.6 Relationships Between Parameters 872
19.7 Interconnection of Networks 875
19.8 Computing Two-Port Parameters Using PSpice 881
19.9 Applications 884
19.9.1 Transistor Circuits
19.9.2 Ladder Network Synthesis
19.10 Summary 893
Review Questions 894
Problems 894
Comprehensive Problem 905
Appendix A Simultaneous Equations and Matrix
Inversion A
Appendix B Complex Numbers A-9
Appendix C Mathematical Formulas A-16
Appendix D Answers to Odd-Numbered
Problems A-21
Charles K. Alexander，分别于1967年和1971年获得俄亥俄大学的电气工程学硕士学位和博士学位，目前为美国克利夫兰州立大学Fenn工学院电气与计算机工程系教授以及电子学与航空航天技术研究中心（CREATE）的主任。他是IEEE的会士，曾任IEEE主席和CEO。他于1984年获得IEEE百年纪念奖章，还先后荣获英国工程委员会颁发的杰出工程教育成就奖和杰出工程教育领导奖。 Matthew N.O.Sadiku，博士，美国Prairie View A&M大学教授，兼任IEEE Transacfions on Education杂志副主编。他曾在朗讯、波音等公司从事研发工作，发表过百余篇学术论文，出版过20余部著作。
Charles K. Alexander, Matthew N. O. Sadiku：Fundamentals of Electric Circuits, Fifth Edition (ISBN：978-0-07-338057-5).
Copyright 2013 by The McGraw-Hill Companies, Inc.
All Rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including without limitation photocopying, recording, taping, or any database, information or retrieval system, without the prior written permission of the publisher.
This authorized Bilingual edition is jointly published by McGraw-Hill Education (Asia) and China Machine Press. This edition is authorized for sale in the People抯 Republic of China only, excluding Hong Kong, Macao SARs and Taiwan.
Copyright 2013 by McGraw-Hill Education (Asia), a division of the Singapore Branch of The McGraw-Hill Companies, Inc. and China Machine Press.
Copyright 2013 by The McGraw-Hill Companies, Inc.
All Rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including without limitation photocopying, recording, taping, or any database, information or retrieval system, without the prior written permission of the publisher.
This authorized Bilingual edition is jointly published by McGraw-Hill Education (Asia) and China Machine Press. This edition is authorized for sale in the People抯 Republic of China only, excluding Hong Kong, Macao SARs and Taiwan.
Copyright 2013 by McGraw-Hill Education (Asia), a division of the Singapore Branch of The McGraw-Hill Companies, Inc. and China Machine Press.
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