by Siu Chi Sang Obadiah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 66-68). / Abstracts in English and Chinese. / Chapter 1 --- Pseudorandom Number Generator --- p.5 / Chapter 1.1 --- Introduction --- p.5 / Chapter 1.2 --- Statistical Indistingushible and Entropy --- p.7 / Chapter 1.3 --- Example of PNG --- p.9 / Chapter 2 --- Basic Knowledge of Cellular Automata --- p.12 / Chapter 2.1 --- Introduction --- p.12 / Chapter 2.2 --- Elementary and Totalistic Cellular Automata --- p.14 / Chapter 2.3 --- Four classes of Cellular Automata --- p.17 / Chapter 2.4 --- Entropy --- p.20 / Chapter 3 --- Theoretical analysis of the CA PNG --- p.26 / Chapter 3.1 --- The Generator --- p.26 / Chapter 3.2 --- Global Properties --- p.27 / Chapter 3.3 --- Stability Properties --- p.31 / Chapter 3.4 --- Particular Initial States --- p.33 / Chapter 3.5 --- Functional Properties --- p.38 / Chapter 3.6 --- Computational Theoretical Properties --- p.42 / Chapter 3.7 --- Finite Size Behaviour --- p.44 / Chapter 3.8 --- Statistical Properties --- p.51 / Chapter 3.8.1 --- statistical test used --- p.54 / Chapter 4 --- Practical Implementation of the CA PNG --- p.56 / Chapter 4.1 --- The implementation of the CA PNG --- p.56 / Chapter 4.2 --- Applied to the set of integers --- p.58 / Chapter 5 --- Application to Cryptography --- p.61 / Chapter 5.1 --- Stream Cipher --- p.61 / Chapter 5.2 --- One Time Pad --- p.62 / Chapter 5.3 --- Probabilistic Encryption --- p.63 / Chapter 5.4 --- Probabilistic Encryption with RSA --- p.64 / Chapter 5.5 --- Prove yourself --- p.65 / Bibliography

Chan Ming-Ho Gordon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 104-105). / Abstracts in English and Chinese. / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- BACKGROUND ON MICRO POWER SUPPLY --- p.1 / Chapter 1.1.1 --- Brief Introduction --- p.1 / Chapter 1.1.2 --- Proposed Applications of Micro Power Supplies --- p.3 / Chapter 1.1.3 --- Comparison Among Different Power Sources --- p.4 / Chapter 1.2 --- LITERATURE SURVEY --- p.8 / Chapter CHAPTER 2 --- MICRO POWER GENERATOR WITH COPPER SPRINGS --- p.10 / Chapter 2.1 --- POWER PRODUCTION FROM MECHANICAL VIBRATIONS: SYSTEM ANALYSIS --- p.10 / Chapter 2.2 --- DESIGN OF MICRO RESONATING SPRING --- p.16 / Chapter 2.2.1 --- Design Objective --- p.16 / Chapter 2.2.2 --- Material Selection --- p.18 / Chapter 2.2.2.1 --- Mechanical Resonating Structure --- p.18 / Chapter 2.2.2.2 --- Electromagnetic Structure --- p.23 / Chapter 2.3 --- LASER MICROMACHINING OF SPRING STRUCTURE --- p.26 / Chapter 2.3.1 --- Si Bulk Micromachining --- p.26 / Chapter 2.3.2 --- Laser Micromachining --- p.28 / Chapter CHAPTER 3 --- COMPUTER SIMULATION --- p.31 / Chapter 3.1 --- TRANSIENT VOLTAGE AND POWER OUTPUT --- p.31 / Chapter 3.2 --- SYSTEM RESPONSE WITH VARYING PARAMETERS --- p.35 / Chapter CHAPTER 4 --- FINITE ELEMENT ANALYSIS --- p.39 / Chapter 4.1 --- STRUCTURAL STATIC ANALYSIS --- p.41 / Chapter 4.1.1 --- Building a Model --- p.41 / Chapter 4.1.2 --- "Material, Loading And Boundary Condition" --- p.45 / Chapter 4.1.3 --- Comparison Between Generator Designs --- p.46 / Chapter 4.2 --- MODAL ANALYSIS AND HARMONIC RESPONSE ANALYSIS --- p.51 / Chapter 4.3 --- NONLINEARITY --- p.52 / Chapter CHAPTER 5 --- COMPARISON OF MODELING AND EXPERIMENTAL RESULTS --- p.55 / Chapter 5.1 --- EXPERIMENT SETUP --- p.55 / Chapter 5.1.1 --- Generator System --- p.55 / Chapter 5.1.2 --- Vibration and Measurement --- p.60 / Chapter 5.2 --- MODELING AND EXPERIMENTAL COMPARISON --- p.62 / Chapter 5.2.1 --- Voltage and Power Comparison --- p.64 / Chapter 5.2.2 --- Mechanical Response --- p.66 / Chapter CHAPTER 6 --- SUGGESTIONS FOR POWER GENERATOR WITH RESONATING FREQUENCY BELOW 10HZ --- p.77 / Chapter CHAPTER 7 --- CONCLUSION --- p.80 / BIBLIOGRAPHY --- p.104

by Yuen Ching Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 61-[63]). / Abstract also in Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Why use cryptography? --- p.1 / Chapter 1.2 --- Why is authentication important ？ --- p.2 / Chapter 1.3 --- What is the relationship between authentication and digital sig- nature? --- p.3 / Chapter 1.4 --- Why is random number important? --- p.3 / Chapter 2 --- Background --- p.5 / Chapter 2.1 --- Cryptography --- p.5 / Chapter 2.1.1 --- Symmetric key cryptography --- p.5 / Chapter 2.1.2 --- Asymmetric key cryptography --- p.7 / Chapter 2.1.3 --- Authentication --- p.8 / Chapter 2.2 --- Elliptic curve cryptography --- p.9 / Chapter 2.2.1 --- Mathematical background for Elliptic curve cryptography --- p.10 / Chapter 2.3 --- Pseudorandom number generator --- p.12 / Chapter 2.3.1 --- Linear Congruential Generator --- p.13 / Chapter 2.3.2 --- Inversive Congruential Generator --- p.13 / Chapter 2.3.3 --- PN-sequence generator --- p.14 / Chapter 2.4 --- Digital Signature Scheme --- p.14 / Chapter 2.5 --- Babai's lattice vector algorithm --- p.16 / Chapter 2.5.1 --- First Algorithm: Rounding Off --- p.17 / Chapter 2.5.2 --- Second Algorithm: Nearest Plane --- p.17 / Chapter 3 --- Several Digital Signature Schemes --- p.18 / Chapter 3.1 --- DSA --- p.19 / Chapter 3.2 --- Nyberg-Rueppel Digital Signature --- p.21 / Chapter 3.3 --- EC.DSA --- p.23 / Chapter 3.4 --- EC-Nyberg-Rueppel Digital Signature Scheme --- p.26 / Chapter 4 --- Miscellaneous Digital Signature Schemes and their PRNG --- p.29 / Chapter 4.1 --- DSA with LCG --- p.30 / Chapter 4.2 --- DSA with PN-sequence --- p.33 / Chapter 4.2.1 --- Solution --- p.35 / Chapter 4.3 --- DSA with ICG --- p.39 / Chapter 4.3.1 --- Solution --- p.40 / Chapter 4.4 --- EC_DSA with PN-sequence --- p.43 / Chapter 4.4.1 --- Solution --- p.44 / Chapter 4.5 --- EC一DSA with LCG --- p.45 / Chapter 4.5.1 --- Solution --- p.46 / Chapter 4.6 --- EC-DSA with ICG --- p.46 / Chapter 4.6.1 --- Solution --- p.47 / Chapter 4.7 --- Nyberg-Rueppel Digital Signature with PN-sequence --- p.48 / Chapter 4.7.1 --- Solution --- p.49 / Chapter 4.8 --- Nyberg-Rueppel Digital Signature with LCG --- p.50 / Chapter 4.8.1 --- Solution --- p.50 / Chapter 4.9 --- Nyberg-Rueppel Digital Signature with ICG --- p.51 / Chapter 4.9.1 --- Solution --- p.52 / Chapter 4.10 --- EC- Nyberg-Rueppel Digital Signature with LCG --- p.53 / Chapter 4.10.1 --- Solution --- p.54 / Chapter 4.11 --- EC- Nyberg-Rueppel Digital Signature with PN-sequence --- p.55 / Chapter 4.11.1 --- Solution --- p.56 / Chapter 4.12 --- EC-Nyberg-Rueppel Digital Signature with ICG --- p.56 / Chapter 4.12.1 --- Solution --- p.57 / Chapter 5 --- Conclusion --- p.59 / Bibliography --- p.61

In traditional Permanent Magnet Machines, such as electric motors and generators, power is transmitted by magnetic flux passing through an air gap, which has a very low magnetic permeability, limiting performance. However, reducing the air gap through traditional means carries risks in manufacturing, with tight tolerances and associated costs, and reliability, with thermal and dynamic effects requiring adequate clearance. Using a magnetically permeable, high dielectric strength material has the potential to improve magnetic performance, while at the same time offering performance advantages in heat transfer. Ferrofluids were studied as a method for improved permeability in the rotor / stator gap with a combined experimental and computational approach. Results show promise for the ferrofluid technique. An off-the-shelf motor system showed improved performance with ferrofluids vs. fluids of equivalent viscosity, and improved performance vs. an air gap at low RPM. New generator designs showed design dependent performance gains, although some potential for negative performance effects. A proof of concept generator was built and tested, with increased voltage vs. RPM predicted through virtual prototyping, and validated through experimentation, showing ~10% improvement on voltage vs. RPM at the <600 RPM range. More repeatable engineering tests demonstrated a ~30% increase in the voltage / RPM relationship for designs with an isolated stator chamber and a large stator - rotor gap. However, the effects were negative for a similar system with a small stator-rotor gap due to leakage flux effects. New contributions to the body of knowledge in this area include: • Application of the ferrofluid technique to axial flux designs. • Development of a virtual prototype, including variations in the fluid viscosity due to ferrohydrodynamic effects. • Consideration of negative effects of ferrofluid immersion, such as shear losses and increases in leakage flux. • Optimization of the design to eliminate increased viscous losses. The improved design has been designed, built, and tested, featuring isolation of the ferrofluid from the rotating region. This offers all of the performance gain of improved magnetic permeability, while minimizing the offsetting losses from increased shear effects.

xiii, 370 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical Engineering, 1980

The coordination of reproductive events in female locusts involves the interaction between sensory cells, reflex loops, and central pattern generators. Neurochemicals have also been identified as being important for initiating and/or modulating the activities of reproductive tissues. The present thesis investigates the association of neurochemicals with the spermatheca and the neural control of the spermatheca via a central pattern generator (CPG) that is coordinated with other reproductive events. Crustacean cardioactive peptide (CCAP)-like immunoreactivity is present in the innervation to the spermatheca of adult locusts. CCAP enhances basal tonus, spontaneous and neurally-evoked contractions and may function as a neuromodulator/neurotransmitter at the locust spermatheca. No locustatachykinin (LomTK)-like immunoreactivity is present in the innervation to the spermatheca, or on the spermatheca itself, whereas allatostatin-like immunoreactivity is present. LomTK1 is a stimulator of spermathecal contractions, but allatostatin 1 does not lead to any changes in spermathecal contractions. It is likely that LomTK acts as a neurohormone on the spermatheca, while the role of allatostatin remains unknown. Tyramine-like immunoreactivity is present in the nerves that project to the spermatheca and throughout all of its regions. Quantification of tyramine revealed that there is more tyramine than octopamine present in the spermatheca, and that tyramine can be released from the spermatheca by electrical stimulation of the ventral ovipositor nerve (VON). Physiological assays reveal that both tyramine and octopamine increase spermathecal contractions. Tyramine may be a co-transmitter with octopamine at the locust spermatheca. There is likely a central pattern generator (CPG) that controls the spermathecal muscle activity, that is regulated by descending inhibition. Extracellular nerve and electromyographic recordings demonstrate that this CPG appears to be localized within the VIIth and VIIIth abdominal ganglia and is found to integrate with the CPG that regulates oviposition digging in locusts.

The coordination of reproductive events in female locusts involves the interaction between sensory cells, reflex loops, and central pattern generators. Neurochemicals have also been identified as being important for initiating and/or modulating the activities of reproductive tissues. The present thesis investigates the association of neurochemicals with the spermatheca and the neural control of the spermatheca via a central pattern generator (CPG) that is coordinated with other reproductive events. Crustacean cardioactive peptide (CCAP)-like immunoreactivity is present in the innervation to the spermatheca of adult locusts. CCAP enhances basal tonus, spontaneous and neurally-evoked contractions and may function as a neuromodulator/neurotransmitter at the locust spermatheca. No locustatachykinin (LomTK)-like immunoreactivity is present in the innervation to the spermatheca, or on the spermatheca itself, whereas allatostatin-like immunoreactivity is present. LomTK1 is a stimulator of spermathecal contractions, but allatostatin 1 does not lead to any changes in spermathecal contractions. It is likely that LomTK acts as a neurohormone on the spermatheca, while the role of allatostatin remains unknown. Tyramine-like immunoreactivity is present in the nerves that project to the spermatheca and throughout all of its regions. Quantification of tyramine revealed that there is more tyramine than octopamine present in the spermatheca, and that tyramine can be released from the spermatheca by electrical stimulation of the ventral ovipositor nerve (VON). Physiological assays reveal that both tyramine and octopamine increase spermathecal contractions. Tyramine may be a co-transmitter with octopamine at the locust spermatheca. There is likely a central pattern generator (CPG) that controls the spermathecal muscle activity, that is regulated by descending inhibition. Extracellular nerve and electromyographic recordings demonstrate that this CPG appears to be localized within the VIIth and VIIIth abdominal ganglia and is found to integrate with the CPG that regulates oviposition digging in locusts.

ABSTRACT The design and fabrication of a rotating electromagnetic generator of low-speed and small bicycle were presented in this study. In accordance with the standard of generator the finite element analysis was used to design the prototype generator. In the simulation, the different parameters of the magnet, coil and iron yoke were set into the Taguchi method to find the best configuration. The parameters included the magnet poles, coil size, wire thickness, winding way, with or without iron yoke, and the distance between the magnet and yoke. When a permanent magnet is moved relative to a coil, an electromotive force is created. According to the theory of electromagnetic induction, the electricity was generated by the electromagnetic power generator. In this study, power produced by the relative motion between coil and magnet. This project innovatively uses Low-Temperature Co-fired Ceramic(LTCC) technology to fabricate micro-coil, and the required magnetic characteristics of permanent magnet are produced by sintered Nd-Fe-B. The technology and simulation were combined to achieve the requirements of lightweight, compact, high energy density. A prototype of the micro-generator is 50x50x4.5 mm3 in volume size. The 28 poles hard magnet Nd/Fe/B with an outer diameter of 50 mm and a thickness of 2 mm was molded and sintered, and provides the magnetic field of 3.5 Tesla. The coils with a width of 200£gm, a pitch 100£gm and the thickness of 40£gm were fabricated by silver. The coils had 30 layers and 22 poles. A steel yoke can improve the efficiency of power generation. The results of induced electromotive force were 0.61, 0.97 and 1.45V at the rotational speeds of 37rpm, 74rpm and 111rpm respectively in the simulation.

Synchronous generators play a vital role in power systems. One of the major mechanical faults in synchronous generators is related to bearings. The popular vibration analysis method has been utilized to detect bearing faults for years. However, bearing health monitoring based on vibration analysis is expensive. One of the reasons is because vibration analysis requires costly vibration sensors and the extra costs associated with its proper installation and maintenance. This limitation prevents continuous bearing condition monitoring, which gives better performance for rolling element bearing fault detection, compared to the periodic monitoring method that is a typical practice for bearing maintenance in industry. Therefore, a cost effective alternative is necessary. In this study, a sensorless bearing fault detection method for synchronous generators is proposed based on the analysis of electrical signatures, and its bearing fault detection capability is demonstrated. Experiments with staged bearing faults are conducted to validate the effectiveness of the proposed fault detection method. First, a generator test bed with an in- situ bearing damage device is designed and built. Next, multiple bearing damage experiments are carried out in two vastly different operating conditions in order to obtain statistically significant results. During each experiment, artificially induced bearing current causes accelerated damage to the front bearing of the generator. This in-situ bearing damage process entirely eliminates the necessity of disassembly and reassembly of the experimental setup that causes armature spectral distortions. The electrical fault indicator is computed based on stator voltage signatures without the knowledge of machine and bearing specific parameters. Experimental results are compared using the electrical indicator and a vibration indicator that is calculated based on measured vibration data. The results indicate that the electrical indicator can be used to analyze health degradation of rolling element bearings in synchronous generators in most instances. Though the vibration indicator enables early bearing fault detection, it is found that the electrical fault indicator is also capable of detecting bearing faults well before catastrophic bearing failure.

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Julian, Alexander L. Second Reader: Cristi, Roberto. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Double Fed Induction Generator (DFIG), Space Vector Modulation (SVM), wind turbine, Field Programmable Gate Array (FPGA), bi-directional power flow. Includes bibliographical references (p. 75). Also available in print.