Items where Subject is "Engineering and Technology > Electrical Engineering > Power Systems"
Group by: Creators | Item Type
Number of items at this level: 185.
Agrawal , Ankesh Kumar (2013) Optimal Controller Design for Twin Rotor MIMO System. MTech thesis.
Behera, Niranjan (2013) Load frequency control of power system. MTech thesis.
Behera, Sandeep (2013) Solution To Constrained Economic Load Dispatch. BTech thesis.
Ekka, Sushmita (2014) Automatic load frequency control of multi area power systems. MTech thesis.
Jain, Suman and Rana, Jyoti Prakash (2013) Design and Simulation of some Controllers for Speed Control of Chopper fed DC Motor. BTech thesis.
Kanungo, Sibasish (2013) Modelling of loads in power flow analysis. BTech thesis.
Mahato, Usha (2013) Low Gain Controller Design with Regional Pole Placement Constraints. MTech thesis.
Mishra, Debashis (2013) Modeling of breakdown voltage of solid insulating material using artificial neural network. BTech thesis.
Nayak, Madhusmita and Singh, Smrutidhara (2013) Fuzzy logic control of induction motor drive for performance improvement. BTech thesis.
Patnaik, Pranab (2013) Load frequency control in a single area power system. BTech thesis.
Priyadarshi , Prasanna (2013) Optimal Controller Design for Inverted Pendulum System: An Experimental Study. MTech thesis.
R. V. L , Narayana Divakar (2013) Realization of Current control strategies of Shunt Active Power Filter under Unbalanced Load. MTech thesis.
Ray, Sachet and Gupta, Aditya Kumar (2013) Modeling of calibration circuit for partial discharge measurement. BTech thesis.
Sarkar, Mithu (2013) Load flow studies with UPFC power injection model. MTech thesis.
Singh , Bibhu Pratap and Singh , Sumit Kumar and Tarai , Sourav Ranjan (2013) Power Quality Assessment Using Signal Processing and Soft Computing Approach. BTech thesis.
Teella , Sreedhar Kumar (2013) Modeling of Breakdown voltage of Solid Insulating Materials Using Soft Computing Techniques. MTech thesis.
Agrawal, Ashish and Kayal, Srikant and Munshi, Bhaskar (2009) Study of Wind Turbine Driven Doubly Fed Induction Generator (DFIG) Using AC/DC/AC Converter. BTech thesis.
Amara, Chandrasekhar (2013) Adaptive hysteresis based fuzzy controlled shunt active power filter for mitigation of harmonics. MTech thesis.
Anand , Piyush (2016) Power Quality Improvement Using Unified Power Quality Conditioner (UPQC). MTech thesis.
Anumula, Pavan Sandeep and P V, Balakrishna and Deshpande, Chaitanya Arvind (2009) Modeling of Breakdown Voltage of White Minilex Paper in the Presence of Voids Using Fuzzy Logic. BTech thesis.
Anurag, Anup (2013) Decoupled control strategy of grid interactive inverter system with optimal LCL filter design. BTech thesis.
Asmat, Adiba and Ray, Prajna Pallabee (2015) Harmonic Reduction Using SVPWM and Active Harmonic Filter and Their Comparative Analysis. BTech thesis.
Bag, Aurobinda (2018) Development of Adaptive Controllers for Grid Integration of a Three-Phase PV System. PhD thesis.
Bal, Satarupa (2013) Experimental validation of ZVS boost converter with resonant circuit for low power photovoltaic applications. BTech thesis.
Bala , Shiban Kanti (2013) Study of Smart Grid Technology and Its Development in Indian
Bala Krishna, Pagadala (2017) Modular Cascaded H-Bridge Multilevel Inverter with Distributed MPPT for Grid Connected Application. MTech thesis.
Barik, Satyanarayan (2016) Hybrid Solar PV and Wind-Driven PMSG System with Single DC-DC Converter and Hysteresis Inverter. MTech thesis.
Basu, Pranamita and Harichandan, Aiswarya (2009) Power System Stability Studies Using Matlab. BTech thesis.
Behera, Biswasraba (2016) Design of Micro-Grid Protection. MTech thesis.
Behera, Maheswar Prasad (2020) Grid-Tied Photovoltaic System under Non-ideal Source Voltage with Battery Energy Storage. PhD thesis.
Behera, S S (2014) Partial discharge characteristic of electrical trees in polymeric cable insulation. MTech thesis.
Behera, Satyajit and Send, Sudhanshu Sekhar (2015) Characterization of Various Power Quality Disturbances Based on Signal Processing and Artificial Intelligence Scheme. BTech thesis.
Behera , Anil Kumar and Kumar , Satender (2013) Stabilizer Design for a Two Area Power System Network. BTech thesis.
Bengani, Saurav Kumar (2013) Estimation of power system frequency. BTech thesis.
Bhadra , Dibyendu and Meena , Rajnish Kumar (2015) Power Quality Improvement by Harmonic Reduction Using Three Phase Shunt Active Power Filter with p-q & d-q Current Control Strategy. BTech thesis.
Bhardwaj, Chandan and Mishra, Mayank (2013) A Comparative Study Between Priority Assigning Method And Lambda Iteration Method For Unit Commitment Problems. BTech thesis.
Bhatt, Keshav and Pradhan, Om Prakash (2009) Effects of Numerical Oscillation in Switching of Power Transformer Connected To A Power Network. BTech thesis.
Bheemraj, T S (2017) Prediction and Prevention of Load Encroachment for Reliable Operation of Distance Relay. MTech thesis.
Bishi, Monika (2017) Application of Artificial Neural Network and Fuzzy Logic Controller in Power Quality Improvement. MTech thesis.
Chakraborty, Sudipta (2018) PID Controller Design for Integrating Plus Time-Delay Processes. PhD thesis.
Chall, SrinivasaRao (2017) Single-Phase Series Active Compensator Integrated with a Rectifier for Voltage Sags,Swells and Harmonics Mitigation. MTech thesis.
Choudhury, Debasis (2013) Characterization of Power Quality Disturbances using Signal Processing and Soft Computing Techniques. MTech thesis.
Das, Rosalin and Lakra, Anupama (2009) Application of Particle Swarm Optimizer to Economic Load Dispatch Problems. BTech thesis.
Das, Satyajit (2019) Robust Active and Reactive Power Controllers for a Grid Connected Wind Energy Conversion System. PhD thesis.
Dash, Ashish Ranjan (2019) Investigation of Cascaded Multilevel Inverter Based SAF with Alternative Configurations Under Ideal and Nonideal Grid Voltage Conditions. PhD thesis.
Dash, Debendra and Pattnaik, Bhabani Shankar and Mukherjee, Joydeep (2009) Implementation of PWM Based Firing Scheme for Multilevel Inverters Using Microcontroller. BTech thesis.
Dash, K Mahesh and Behera, Makhes Kumar and Angajala, Vamsi Krishna (2014) Load frequency control in an AC microgrid. BTech thesis.
Dash, Monalisa (2007) Harmonic frequency estimation under nonsinusoidal conditions. MTech thesis.
Dash, Smruti (2013) A Lyapunov-Function Based Control For A Three-Phase Shunt Hybrid Active Power Filter. MTech thesis.
Debta, Birendra Kumar (2015) Dynamic Analysis, Voltage Control and Experiments on a Self Excited Induction Generator for Wind Power Application. MTech by Research thesis.
Dey, Diptiman (2019) Design and Real-time Implementation of Adaptive Grid Synchronization Control Schemes for Photovoltaic System. MTech by Research thesis.
Divya, Artham (2015) Performance Analysis of DSOGI PLL under Balanced and Unbalanced Conditions. MTech thesis.
Dora, Gouri Shankar and Madhulita, Monali (2013) Control techniques for power system stabilisation. BTech thesis.
Dwibedy, J S (2014) State estimation through secure wireless communication in a smart grid. MTech thesis.
Dwivedi, Sambit Kumar (2012) Load Modeling in Optimal Power Flow Studies. BTech thesis.
Ekka, D K (2014) Power quality estimation and classification using wavelets. BTech thesis.
Gahir, Kamlesh Kumar (2016) Selection of Line Contingency for Power System Security Analysis. MTech thesis.
George, Noby (2019) Novel Coreless Current Sensing Systems-Design, Development and Evaluation. PhD thesis.
Gochhayat, R (2014) PSO based PI controller for load frequency control of interconnected power systems. MTech thesis.
Gupta, Aditya Kumar (2017) Voltage Profile Improvement and Loss Reduction Using Optimal Location of Shunt Connected Facts Devices. MTech thesis.
Haldar, Abhijeet and Bhadauria, Vishwarath (2012) Power System Stability Enhancement by Simultaneous AC-DC Power Transmission. BTech thesis.
Hemanth, Chaduvula (2015) Point Estimate Method Based Uncertainty Modelling For Distributed Generation Allocation Using Differential Evolutionary Algorithm. MTech thesis.
Hembrom , Shivani (2013) Analysis of aged insulating oil for early detection of incipient fault inside the high voltage equipment. MTech thesis.
J P, Jagannath Prasad Mishra and Paplu, Rutwik Rath (2011) Input Power Factor Correction using Buck Converter in Single Phase AC-DC Circuit. BTech thesis.
Jaiswal, R K (2014) Power system harmonics estimation using different signal processing techniques. MTech thesis.
Javed, Md and Agrawal , Abinash (2015) Simulation and Experiments on One Phase and Three Phase Shunt Active Power Filters. BTech thesis.
Jee, Devraj and Patel, Nikhar (2013) V/f Control of Induction Motor Drive. BTech thesis.
Jena, Sarbajeet (2015) Electromagnetic Effect of High Voltage Transmission Lines on Human Being. MTech thesis.
Jena, Shyamsundar (2014) MATLAB simulation of single phase shunt active power filter and development of experimental set up. BTech thesis.
Jha, Ankit and Kumar, Ashwinee and Ralte, Lathangliana and Pati, Pinak Ranjan (2009) Transient Stability Analysis using Equal Area Criterion using Simulink Model. BTech thesis.
Jha, Pankaj Kumar (2013) Position and Heading Control of an Autonomous
Killi, Muralidhar (2017) Development of Efficient MPPT Algorithms with Reduced Number of Sensors for Photovoltaic Systems. PhD thesis.
Kumar, Anant and Munsh, Shreerang Pradeep and Memon, Mohammed Rehan and Mishra, Sitanshu (2007) Speed control of DC motor using IGBT. BTech thesis.
Kumar, Avinash (2016) Dissolve Gas Analysis Due to Partial Discharge Fault in Transformer Oil. MTech thesis.
Kumar, D Pradeep (2007) Investigations on shunt active power filter for power quality improvement. MTech thesis.
Kumar, Gitesh (2015) UPFC for Analysis of Relay Performance During Power Swing Condition. BTech thesis.
Kumar, Katikala Hem (2015) Contingency Constrained Economic Load Dispatch Using Particle Swarm Optimization For Security Enhancement. MTech thesis.
Kumar, Sunkara Suni (2013) Co-ordinated Design of PSS and TCSC Damping Controllers in Multi-machine Power System using PSO. MTech thesis.
Kumar , Ankush (2013) Controller Design for Fractional-Order Systems. MTech thesis.
Kumar , Avinash (2013) An adaptive hysteresis band current controlled unified power quality conditioner. MTech thesis.
Kumar N, S (2014) Power quality issues and its mitigation techniques. MTech thesis.
Kumari , Neetu (2017) Online Detection of Disturbances in Power System using Least Square Estimation. MTech thesis.
Mahanand, Siddharth and Jena, Tushar Kanti (2015) MATLAB Simulation Model to Improve Voltage Sag Due to Starting of Induction Motor Using STATCOM. BTech thesis.
Mahapatro, Soumya Ranjan (2018) Robust Decentralized Control Algorithms for a Multivariable Liquid Level System. PhD thesis.
Maity, Amrita (2016) Matrix Completion for Data Recovery of Faulty PMU. MTech thesis.
Malik, Alok and Nayak, Biswabhusan (2013) Virtual instrument based fault detection in three phase circuit. BTech thesis.
Malik, Biswanath (2009) Electric Field Calculations by Numerical Techniques. BTech thesis.
Mallick, Amit Kumar and Hota, Bhabani Sankar (2011) Load flow study in power system. BTech thesis.
Mallikarjuna, Neeli (2016) Designing of Rogowski Coil to Detect Partial Discharge Signals in Power Cables. MTech thesis.
Mansing, Hembram (2013) A Cascaded Inverter For Transformerless Single Phase Grid Connected Photovoltaic Systems. BTech thesis.
Mikkili, Suresh (2013) Performance Analysis of Type-1 and Type-2 FLC based Shunt Active Filter Control Strategies for Power Quality Improvement. PhD thesis.
Mishra, Pushanjeet and Panda, Abhisek Kumar (2014) Load balancing and power factor correction in power distribution system. BTech thesis.
Mishra , G (2013) Design of Passive High Pass Filter for Hybrid Active Power Filter Applications. MTech thesis.
Mohapatra, Anurag (2012) Distributed Slack Bus Algorithm for Economic Load Dispatch. BTech thesis.
Mohapatra, Debashish (2015) Development and Hardware Implementation of a Phasor Measurement Unit using Microcontroller. MTech thesis.
Mohapatra, Santosh Kumar and Sinha, Ajay and Bariha, Saroj (2007) Breakdown voltage modelling for leatherite paper dielectrics using fuzzy logic technique & estimating the lifetime using step-stress test. BTech thesis.
Mohapatra , Sidhartha (2013) Power Upgradation by Simultaneous AC-DC Power Transmission System. BTech thesis.
Mondal, Jolly (2014) Modelling and simulation of impulse voltage generator using marx circuit. BTech thesis.
Nagarjuna, M (2014) Voltage quality and power quality factor improvement using active power line conditioner. MTech thesis.
Naik, Biswajit and Mudgal, Nikhil and Behera, Somanath (2014) Load flow analysis of unbalanced radial distribution systems. BTech thesis.
Nanda, P K (2014) Power quality improvement in 3-ϕ power system using shunt active filter with synchronous detection method. BTech thesis.
Narendra, Kinjarapu (2017) Load Frequency Control for a Distributed Grid System Involving Wind and Hydro Power Generation. MTech thesis.
Naveen, Pudi (2016) Wavelet Entropy Based Algorithm for Fault Detection in a Facts Compensated Transmission Line. MTech thesis.
Nayak, Ajitesh and Bhutia, Priyadarsini (2015) Modeling and Simulation of Partial Discharge Pulse Generator. BTech thesis.
Nayak, Ashwini Kumar (2020) Adequacy Assessment of Power System and Capacity Credit Estimation with Renewable Source Integration. PhD thesis.
Nayak, Biswabandhu (2015) Assesment of Power Quality of Photovoltaic Generations. MTech thesis.
Nayak, Rudraa and Sahu, Akshaya Kumar and Yadav, Narendra (2015) Extraction of Symmetrical Components and Fault Indication. BTech thesis.
Nehru, Gugloth (2015) Planning of A Microgrid. MTech thesis.
Obaiah, Maddela Chinna (2019) Wide-Area Damping Controllers for Power System with Time Delays and Actuator Saturation. PhD thesis.
Padhi, Shyama Sundar (2015) Assessment of Power Quality Events by Hilbert Transform Based Neural Network. MTech thesis.
Pal, Aurabind and Ratha, Anubhav and Mishra, Vaibhav and Garg, Anshul (2011) Development of a smart grid for the proposed 33 KV ring main Distribution System in NIT Rourkela. BTech thesis.
Panda, Piyush (2012) Study of the FACTS Equipment Operation in Transmission Systems. BTech thesis.
Panda, Smruti Ranjan (2013) Phase Estimation for Grid Synchronization of DG System Using Cordic Algorithm. BTech thesis.
Panda, Soumya Ranjan (2013) Distributed Slack Bus Model for Qualitative Economic Load Dispatch. BTech thesis.
Panda, Swastik Sovan (2016) Power Quality Disturbance Detection and Classification. BTech thesis.
Panigrahi, Bibhu Prasad and Pradhan, Abhijit (2011) Modern methods for power system harmonics estimation. BTech thesis.
Panigrahi, Premananda (2013) Topological Analysis of Power Grid to Identify Vulnerable Transmission Lines and Nodes. MTech thesis.
Panigrahy, Sarita (2013) Studies of short channel effects and
Patel, Abhilash (2015) Study on Wide-Area Controller Design and Effect of Delays in Power Systems. MTech thesis.
Patel, Kishan Kumar (2015) Development and Real-time Dynamic Positioning of an Unmanned Ground Vehicle. BTech thesis.
Patel, Subham Swagat and Sethy, Sanat Kumar and Lal, Satyajeet (2015) Detection of Faults in the Tranmission Lines by Using 8051 Microcontroller. BTech thesis.
Patnaik, K and Samantaray, B (2010) A Study of Wind Energy Potential in India. BTech thesis.
Patnaik, Sushree Sangita (2015) Performance Enhancement of Shunt APFs Using Various Topologies, Control Schemes and Optimization Techniques. PhD thesis.
Pattnaik, Swapnajit (2011) Development of Improved Performance Switchmode Converters for Critical Load Applications. PhD thesis.
Penthia, Trilochan (2018) Performance Analysis and Application of Superconducting Magnetic Energy Storage in a Power System. PhD thesis.
Prabhu , G. S. C. Trinath (2013) Harmonic Estimation Of Distorted Power Signals Using PSO – Adaline. MTech thesis.
Pradhan, Alok Kumar (2012) Analysis of partial discharge signals using digital signal processing techniques. MTech thesis.
Pradhan, Anshuman (2016) Estimation and Elimination of Power System Harmonics and Implementation of Kalman Filter Algorithm. MTech thesis.
Pradhan, Rosy (2013) Algorithm for online estimation of power system parameters. MTech thesis.
Purohit, Ashirbad (2015) Partial Discharge Modelling and Measurement of HV Insulation. MTech thesis.
Rajak, Suman Kumar (2017) Design of Power System Stabilizer (PSS) for small signal stability analysis of Power system. MTech thesis.
Ramakrishna , Dommati (2007) Design, testing and assembly of rectangular patch antenna. MTech thesis.
Rana, G and Badu, A J (2014) Study of power quality assessment for a photo-voltaic based Distribution Static Compensator (DSTATCOM). BTech thesis.
Ranjan, Rajeev (2016) Modelling and Simulation of a Photovoltaic System with MPPT Controller. BTech thesis.
Ratha, Bedaprakash and Mishra, Tushar (2012) A Study of Partial Discharge Characteristics in High Voltage Insulators. BTech thesis.
Raveendra, Kesana (2015) Power Quality Improvement of Single Phase Grid Connected Photo Voltaic System. MTech thesis.
Ravi, Dakkamadugula (2015) Study on Some Pid Tuning Methods using Simulation. BTech thesis.
Reddy, D Raghu Rama (2007) Improving transient stability of power systems by using passivity-bassed nonlinear STATCOM controller. MTech thesis.
Reddy , N Veeranji (2014) Dissolved Gas Analysis–An Early Identification of Faults in High Voltage Power Equipment using MATLAB GUI. MTech thesis.
Rentala , D B and Das, M (2014) A Novel method to Detect and Evaluate Power Quality disturbances using Hilbert Phase Shifting and CORDIC Algorithm. BTech thesis.
Rout, Rashmi Ranjan and Tripathy, Durga Prasad (2009) AC to DC Converter Using Microcontroller. BTech thesis.
Rout , Nirakar and Sethy , Jagadish Kumar (2014) Implementation of fuzzy logic controller for load frequency control in two area power system. BTech thesis.
Routray, Tapaswini (2016) Load Frequency Control of Multi-Area Power System Using Different Optimization Techniques. MTech thesis.
Saha, Anirban (2016) Dissolved Gas Analysis of Transformer Oil Due to Thermal Effect. MTech thesis.
Sahu, Rakesh Kumar and Mahapatra , Debasish (2013) Comparative study between active and hybrid power filters for power quality enhancement. BTech thesis.
Saikia, Himanshu Jyoti (2017) Development of a Fuzzy Based Algorithm for Islanding Detection of a Grid Connected DG. MTech thesis.
Samal, S K (2014) Power system stability enhancment using UPFC damping controller. MTech thesis.
Samal, Simanta Kumar (2015) Measurement of Voltage Distribution on High Voltage Suspension Insulator String Under Polluted Condition. MTech thesis.
Samal, Sudhansu Kumar (2020) Estimation of Low-Frequency Oscillations Using Wide-Area Monitoring in Power System. PhD thesis.
Samantaray, S R (2007) A New Approach to Power System Protection using Time-frequency Analysis and Pattern Recognition. PhD thesis.
Sandeep, A (2014) Study of hybrid active power filter for power quality improvement. MTech thesis.
Sandeep, Tarra (2016) Detection of Partial Discharge in A 33kv XLPE Underground Cable and the Effects on its Insulation. MTech thesis.
Sarkar, Mithu (2019) Robust Wide-Area Damping Controllers for compensating Inter-Area Oscillations in Power System. PhD thesis.
Sarkar, S (2014) Power quality disturbance detection and classification using signal processing and soft computing techniques. MTech thesis.
Saswat, S (2014) Study of single phase shunt active power filter. BTech thesis.
Satpathy, Subhransu and Bebarta, Siddharth Shankar (2013) Power Quality Improvement in 3 – Phase System Using Shunt Active Filter. BTech thesis.
Sebastian, Sharon (2016) Grid Connected Photovoltaic Power System with Active Power Filtering. MTech thesis.
Senapati, Sambit Kumar and Krishna, A. V. Jay and Rohit , Kumar (2014) Development of microcontroller based over-current relay controls. BTech thesis.
Sethi, Neeraj (2015) Detection of Partial Discharge in High Voltage Power Equipment under Sinusoidal Applied Voltage. BTech thesis.
Sha, Akash Kumar and Moktan, Budhi Man (2015) Study of Reactive Power Compensation Using Fact Devices. BTech thesis.
Sharma, Jayant (2015) Design and Modelling Of FACTS Devices. MTech thesis.
Shinde, N (2014) Power system frequency estimation using linear and nonlinear techniques. MTech thesis.
Shukla, Amit Kumar (2009) Studies on Power Quality and, an LSE & PSOPC based Harmonic Estimation to Real Time Data. BTech thesis.
Siddhartha, C V Srinivasa and Bharath, Gorja Chaitanya and Behera, Chinmayee (2015) Harmonics and Phasor Estimation for a Distorted Power System Signal. BTech thesis.
Singh, Ashish Kumar and ChandraPrakash, Suluganti (2013) Effect of impulse voltage on solid insulation. BTech thesis.
Singh, Deepak Kumar and Hota, Janmejaya and Nayak, Satyajeet (2012) Novel Application of LabVIEW in High Voltage Engineering. BTech thesis.
Sinku, Rajiv Kumar (2015) Study of Unified Power Quality Conditioner for Power Quality Improvement. MTech thesis.
Soren, Sanjay Kumar (2015) Single Phase Grid Connected PV System. MTech thesis.
Srikant, A and Pradhan, S C (2011) Simulation of air breakdown mechanism using different electrodes. BTech thesis.
Suman, Ganesh Kumar and Sethi, Suchit Kumar (2014) Modelling of doubly fed induction generator connected with a wind turbine. BTech thesis.
Sundaria, Anubhav (2016) A Study on Fault Tolerant Wide-Area Controller Design to Damp Inter-Area Oscillations in Power Systems. MTech thesis.
Swain, Saumya Ranjan (2015) Analysis of Partial Discharge Signals Using Stockwell Transform. MTech thesis.
Swain, Sudarshan (2019) Grid Synchronization Control Schemes for a Three Phase Grid connected Photovoltaic System with Power Quality Disturbances. PhD thesis.
Swain , Bhanja Kishor (2007) Design of low noise high power RF amplifier using bipolar junction transistors. MTech thesis.
T, Purna Chandra Rao (2007) An accurate frequency estimation in power networks in the presence of harmonics. MTech thesis.
Tandan, G Roshan (2016) Detection of Large Signal Disturbances by Least Square Estimation Technique. MTech thesis.
Taram, Dev Kumar (2015) Power Quality Improvement Using Dynamic Voltage Restorer (DVR). MTech thesis.
Teja, CH H S Ravi (2013) Analysis of grid synchronization techniques for distributed generation system during grid abnormalities. MTech thesis.
Thatoi, Padmaja and Pradhan, Aradhana (2012) Study on the performance of newton – raphson load
Tikader, Ripan (2014) Energy management at municipal parking deck for charging of plug-in hybrid electric vehicles with differential evolution. MTech thesis.
Tirkey, Prem Sai and Chiruvolu, Naganaveen Kumar (2015) Speed Control and Regenerative Braking of Bidirectional DC-DC Converter Fed Permanent Magnet DC Motor. BTech thesis.
Varaprasad, Madisa V G (2020) Analysis and Design of an Efficient PV Power Optimizer with Reduced EMI Effects and Less Sensors Counts. PhD thesis.