| LIST OF CONTENT | 第5-8页 |
| LIST OF FIGURES | 第8-10页 |
| LIST OF TABLES | 第10-11页 |
| ABSTRACT | 第11页 |
| CHAPTER Ⅰ:INTRODUCTION | 第12-16页 |
| 1.1 objectives and problems statement | 第14-16页 |
| 1.1.1 Problems statement | 第14-15页 |
| 1.1.2 Objectives of the study | 第15-16页 |
| CHAPTER Ⅱ:LITERATURE REVIEW | 第16-30页 |
| 2.1 Diesel engine defect detection and monitoring methods | 第16-20页 |
| 2.1.1 Vibration signal method | 第16-20页 |
| 2.2 The vibration excitation sources of the diesel engine | 第20-26页 |
| 2.2.1 Vibration response | 第21-23页 |
| 2.2.2 Main sources of diesel engine noise | 第23-26页 |
| 2.3 Time domain analysis | 第26-30页 |
| 2.3.1 Feature extraction and selection from vibration signal | 第27页 |
| 2.3.2 Time or statistical analysis | 第27页 |
| 2.3.3 Standard deviation (SD) | 第27页 |
| 2.3.4 Root mean square (RMS) | 第27-28页 |
| 2.3.5 Peak level | 第28页 |
| 2.3.6 Crest factor | 第28-29页 |
| 2.3.7 Shape factor (SF) | 第29页 |
| 2.3.8 Kurtosis | 第29页 |
| 2.3.9 Skewness | 第29-30页 |
| CHAPTER Ⅲ:MATERIALS AND METHODS | 第30-79页 |
| 3.1 Materials and hardware design of fault diagnosis system | 第30-38页 |
| 3.1.1 Location of experiment | 第30页 |
| 3.1.2 The test diesel engine of experimental study | 第30-32页 |
| 3.1.3 The CW40 electric dynamometer | 第32-33页 |
| 3.1.4 Charge amplifier YE5853A | 第33页 |
| 3.1.5 NI-Data acquisition card PCI 6040 E | 第33-35页 |
| 3.1.6 Shielded connection box (SCB-68) | 第35-36页 |
| 3.1.7 Piezoelectric acceleration sensor-type CA-YD-106 | 第36页 |
| 3.1.8 Personal computer | 第36页 |
| 3.1.9 Lab VIEW software and engine accelerated vibration signal acquisition system | 第36-38页 |
| 3.1.10 The virtual instrument construction and operation | 第38页 |
| 3.2 Selection method for signal processing | 第38-48页 |
| 3.2.1 Introduction | 第38-40页 |
| 3.2.2 Wavelet transform method | 第40-42页 |
| 3.2.3 Continuous wavelet transforms | 第42-44页 |
| 3.2.4 Multi-resolution analysis | 第44-48页 |
| 3.3 Signal denoising | 第48-52页 |
| 3.3.1 The threshold denoising method | 第48-49页 |
| 3.3.2 Types of thresholding | 第49-52页 |
| 3.4 Experimental settings and parameters selection | 第52-61页 |
| 3.4.1 Setup of the experiment | 第52-54页 |
| 3.4.2 Sensors installation on the diesel engine head | 第54页 |
| 3.4.3 The selected sampling frequency and sampling points | 第54-55页 |
| 3.4.4 Selection method for signal denoising | 第55-56页 |
| 3.4.5 Selection of the optimum threshold level and mother wavelet | 第56-61页 |
| 3.4.6 Selection of mother wavelet and wavelet decomposition level for signal | 第61页 |
| 3.5 Results and discussion | 第61-79页 |
| 3.5.1 Wavelet analysis on cylinder head vibration signal | 第61-75页 |
| 3.5.2 Characteristics of the signal energy and fault detection | 第75-76页 |
| 3.5.3 Results of the analysis of time domain features extracted | 第76-79页 |
| CHAPTER Ⅳ:BACK PROPAGATION NEURAL NETWORK AND SUPPORT VECTOR MACHINE | 第79-94页 |
| 4.1 Back propagation neural network and support vector machine | 第79-83页 |
| 4.1.1 Back propagation neural network (BPNN) | 第79-80页 |
| 4.1.2 Architecture of backward propagation neural network | 第80-83页 |
| 4.2 Support vector machine and signal pattern recognition | 第83-88页 |
| 4.2.1 Construction of SVM algorithm | 第84-88页 |
| 4.3 Results and discussions | 第88-94页 |
| 4.3.1 Design of the back-propagation (BP) network | 第88-89页 |
| 4.3.2 Design of the support vector machine training | 第89-90页 |
| 4.3.3 Features extracted using SVM and BPNN | 第90-94页 |
| CHAPTER Ⅴ:CONCLUSIONS AND RECOMMENDATIONS | 第94-96页 |
| 5.1 Conclusions | 第94-95页 |
| 5.2 Recommendations and future studies | 第95-96页 |
| ACKNOWLEDGMENTS | 第96-97页 |
| BIBLIOGRAPHY | 第97-106页 |
| APPENDIX A:Ⅵ, FRONT PANEL AND BLOCK DIAGRAM | 第106-107页 |
