This research presents a solution to the problem of tuning a PID controller for a nonlinear system. Many systems in industrial applications use a PID controller to control a plant or the process. Conventional PID controllers work in linear systems but are less effective when the plant or the process is nonlinear because PID controllers cannot adapt the gain parameters as needed. In this research we design a Nonlinear PID (NPID) controller using a fuzzy logic system based on the Mamdani type Fuzzy Inference System to control three different DC motor systems. This fuzzy system is responsible for adapting the gain parameters of a conventional PID controller. This fuzzy system's rule base was heuristically evolved using an Evolutionary Algorithm (Differential Evolution). Our results show that a NPID controller can restore a moderately or a heavily under-damped DC motor system under consideration to a desired behavior (slightly under-damped).

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This thesis discusses the General Data Protection Regulation (GDPR) and its impact on individuals since the GDPR became effective in May 2018. The regulation has had significant implications for companies and organizations that handle user data as it provides fines if they are non-compliance. However, the GDPR was created to protect individuals' privacy and personal data in the European Union (EU), which has added many complexities to companies and individuals. This study aims to provide an experiment with individuals in Sweden to document their knowledge of the regulations and their ability to exercise the rights granted and to know their opinions through interviews with 19 samples of individuals. The research deals with the third chapter more than other chapters of the GDPR. The results revealed a lack of awareness among the participants, with only a small percentage having prior knowledge of the GDPR and lacking a clear understanding of the implications and practical implementation of these rights, despite the participants' enthusiasm when explaining the rights to them. Participants acknowledged the importance of their data and assessed the provisions of the GDPR. They emphasized rights such as access, rectification, and erasure as necessary to protect privacy. After obtaining nearly complete knowledge, the participants could exercise and find the GDPR rights entirely on Swedish sites, except those who were able to find the rights with only a little knowledge. The study highlights the need to enhance individuals' awareness of the GDPR and improve transparency and accessibility of privacy policies.

Small electric uninhabited aerial vehicles (UAV) represent a rapidly expanding market requiring optimization in both efficiency and weight; efficiency is critical during cruise or loiter where the vehicle operates at part power for up to 99% of the mission time. Of the four components (battery, motor, propeller, and electronic speed controller (ESC)) of the electric propulsion system used in small UAVs, the ESC has no accepted performance model and almost no published performance data. To collect performance data, instrumentation was developed to measure electrical power in and out of the ESC using the two wattmeter method and current sense resistors; data was collected with a differential simultaneous data acquisition system. Performance of the ESC was measured under different load, commanded throttle, bus voltage, and switching frequency, and it was found that ESC efficiency decreases with increasing torque and decreasing bus voltage and does not vary much with speed and switching frequency. The final instrumentation was limited to low-voltage systems and error propagation calculations indicate a great deal of error at low power measurements; despite these limitations, an understanding of ESC performance appropriate for conceptual design of these systems was obtained. MODELING AND TEST OF THE EFFICIENCY OF ELECTRONIC SPEED CONTROLLERS FOR BRUSHLESS DC MOTORS

High blood pressure, also called hypertension is one of the most common worldwide diseases afflicting humans and is a major risk factor for stroke, myocardial infarction, vascular disease, and chronic kidney disease. If blood pressure is controlled and oscillations in the hemodynamic variables are reduced, patients experience fewer complications after surgery. In clinical practice, this is usually achieved using manual drug delivery. Given that different patients have different sensitivity and reaction time to drugs, determining manually the right drug infusion rates may be difficult. This is a problem where automatic drug delivery can provide a solution, especially if it is designed to adapt to variations in the patient’s conditions. This research work presents an investigation into the development of abnormal blood pressure (hypertension) controllers for postoperative patients. Control of the drugs infusion rates is used to simultaneously regulate the hemodynamic variables such as the Mean Arterial Pressure (MAP) and the Cardiac Output (CO) at the desired level. The implementation of optimal control system is very essential to improve the quality of patient care and also to reduce the workload of healthcare staff and costs. Many researchers have conducted studies earlier on modelling and/or control of abnormal blood pressure for postoperative patients. However, there are still many concerns about smooth transition of blood pressure without any side effect. The blood pressure is classified in two categories: high blood pressure (Hypertension) and low blood pressure (Hypotension). The hypertension often occurred after cardiac surgery, and the hypotension occurred during cardiac surgery. To achieve the optimal control solution for these abnormal blood pressures, many methods are proposed, one of the common methods is infusing the drug related to blood pressure to maintain it at the desired level. There are several kinds of vasodilating drugs such as Sodium Nitroprusside (SNP), Dopamine (DPM), Nitro-glycerine (NTG), and so on, which can be used to treat postoperative patients, also used for hypertensive emergencies to keep the blood pressure at safety level. A comparative performance of two types of algorithms has been presented in chapter four. These include the Internal Model Control (IMC), and Proportional-Integral-Derivative (PID) controller. The resulting controllers are implemented, tested and verified for three sensitivity patient response. SNP is used for all three patients’ situation in order to reduce the pressure smoothly and maintain it at the desire level. A Genetic Algorithms (GAs) optimization technique has been implemented to optimise the controllers’ parameters. A set of experiments are presented to demonstrate the merits and capabilities of the control algorithms. The simulation results in chapter four have demonstrated that the performance criteria are satisfied with the IMC, and PID controllers. On the other hand, the settling time for the PID control of all three patients’ response is shorter than the settling time with IMC controller. Using multiple interacting drugs to control both the MAP and CO of patients with different sensitivity to drugs is a challenging task. A Multivariable Model Reference Adaptive Control (MMRAC) algorithm is developed using a two-input, two-output patient model. Because of the difference in patient’s sensitivity to the drug, and in order to cover the wide ranges of patients, Model Reference Adaptive Control (MRAC) has been implemented to obtain the optimal infusion rates of DPM and SNP. This is developed in chapters five and six. Computer simulations were carried out to investigate the performance of this controller. The results show that the proposed adaptive scheme is robust with respect to disturbances and variations in model parameters, the simulation results have demonstrated that this algorithm cannot cover the wide range of patient’s sensitivity to drugs, due to that shortcoming, a PID controller using a Neural Network that tunes the controller parameters was designed and implemented. The parameters of the PID controller were optimised offline using Matlab genetic algorithm. The proposed Neuro-PID controller has been tested and validated to demonstrate its merits and capabilities compared to the existing approaches to cover wide range of patients. / Libyan Ministry of Higher Education scholarship

This degree project studies the integration of carbon capture system into biomass fired combined heat and power (bio-CHP) plants. The key disturbances from bio-CHP plants include flue gas flow rate, carbon dioxide (CO2) concentration and available heat for the reboiler because the use of versatile biomass and the dynamic operation of CHP plants results in large fluctuations in the properties of flue gas and the heat input for CO2 capture. To clearly understand the impacts of these disturbances on the performance of CO2 capture, a dynamic CO2 capture model is developed in Aspen Plus Dynamics by using monoethanolamine (MEA) based chemical absorption. Proportional-Integral (PI) feedback controllers are then implemented to further study and compare the performance of the CO2 capture process under different control strategies, the performance with general control settings and fine-tuned controllers are obtained and compared, including both the control performance and system performance. The control performance includes the maximum deviation and settling time, which could reflect only the performance of the controllers.  The system performance includes Captured CO2, reboiler duty and Energy penalty per unit CO2 captured, which could reflect CO2 capture system performance. An equilibrium stage steady state model is first developed for the key components in the CO2 capture plant in Aspen Plus, consisting of the absorber, the stripper, and lean-rich heat exchanger. By sizing the components and employing the pressure driven mode, the steady state model is enabled to be a dynamic model. The disturbances about flue gas and reboiler heat are taken from a real bio-CHP plant in Sweden. Considering the higher flue gas flowrate, the model has been scaled up to meet the requirement of this bio-CHP plant. The addition of controllers are done for the flexible operation of the CO2 capture system and the controlled variables considered in this study are the percentage of CO2 absorbed in the absorber column, reboiler temperature and rich solvent flow in the stripper column. The results show the effects of fluctuations in the key influencing factors on the control performance and the system performance . The fine-tuned controller implemented system showcases better performance when the quantity of CO2 captured is compared with that of the system in the absence of controllers, where a 1.1% increase in the amount of captured CO2 is observed when the flue gas flow rate is increased by 30%. The system also maintains a 1.8% higher capture rate when controllers are implemented. This showcases better system performance when controllers are implemented in the system. To further analyse the effects of control strategies two different control strategies are compared where controllers with general settings are compared to the controllers which are fine-tuning achieved by implementing tuning parameters which were obtained through Internal Model control (IMC) based on the system requirements. The fine tuning of the controllers results in improved system performance where the amount of captured CO2 increases by 1.4% when the reboiler duty is increased by 30% and a 1.7% decrease in the energy penalty per unit CO2 captured. Additionally, the results show that the settling time and maximum deviation are different for the two controllers where the controller which underwent fine tuning maintained the steady set point whereas the controller with general controller tuning showcases deviation before it attained stability. Therefore, the fine-tuned controller is more efficient to enable the flexible operation of CO2 capture when facing disturbance. It is studied that the tuning parameters implemented in the controllers affect the transient operation of the plant and improved the dynamic performance of the capture system. The tuned controllers offered more stability to the capture system while attaining their respective set points in a shorter time frame. It is also found that there exists a big difference between the system’s performance without controllers and that with finely tuned controllers. The difference in captured CO2 amount is approximately 26 ton/h when flue gas flow rate increases by 30%. The percentage difference is 1.1%, 7.7% and  5.9% for Captured CO2, reboiler duty and Energy penalty per unit CO2 captured respectively. In conclusion the control of the transient operation of the CO2 capture system needs the control system implemented and requires fine tuning parameters to achieve the desirable performance.

The innovation of electrical utilities in creating smart electrical grids has superseded that of water utilities in analogous efforts. While many water utilities are now using smart water technologies, they lack the virtual command center that allows for two-way communication for more effective forecasting, load balancing, preventive methods, emergency and master planning, and level of service delivery while ensuring environmental justice and enhancing the responsible use of resources. In this dissertation, I propose the idea of the Integrated Water Distribution System (IWDS) to overcome this challenge. IWDS coordinates management of water supply and demand in a way that benefits both the water utility and the customer. IWDS also allows for greater control over monitoring, operation and maintenance, security, asset management, artificial intelligence, and delivery of water in order to maximize economic, environmental, and social welfare. To provide a way forward for IWDS and bring water services onto a technological level equal to that of other infrastructure systems, I call for greater coordination and integration of smart water technology and data, including environmental justice evaluations, and improved customer engagement. As a demand side management (DSM) tool and smart water technology component of IWDS, smart irrigation controllers (SICs) have the potential to ensure water utilities are resilient to growth and can manage peak day demands. SICs, which interface with soil moisture, evapotranspiration, or weather sensors, have been promoted as a demand-side management tool for this purpose. I review the body of research on residential smart irrigation controllers and their effectiveness. I find that smart irrigation controllers consistently reduce water demand by 15% among general users and more than 40% among indulgent users. A hydraulic model simulation using EPANET demonstrates the effectiveness of residential SICs in shifting and shaving peak demands associated with outdoor irrigation. The pressurized irrigation system for Highland, Utah, USA, is modeled with irrigation demands on a baseline scenario compared to an intervention scenario. By employing the intervention, the water system experiences many positive impacts. Without the peak shifting and shaving adjustments, costly additional capital facility improvements would be needed to maintain the same level of service. The model indicates that the SICs, if providing a 30% conservation effect (intervention scenario with SIC conservation), would shave the peak demand allowing for greater optimization and efficiency. This is the first hydraulic model analysis to demonstrate the DSM effectiveness of SICs.

This thesis deals with modeling, simulation and implementation of Load Commutated SCR based current source Inverter (LCI) fed squirrel cage induction motor drive with sinusoidal voltage and sinusoidal current. In the proposed system, the induction motor is fed by an LCI. A three level diode clamped voltage source inverter (VSI) is connected at the motor terminal with ac chokes connected in series with it. The VSI currents are controlled in such a manner that it injects the reactive current demanded by the induction motor and the LCI for successful commutation of the SCRs in the LCI. Additionally, it absorbs the harmonic frequency currents to ensure that the induction motor draws sinusoidal current. As a result, the nature of the motor terminal voltage is also sinusoidal. The concept of load commutation of the SCRs in the LCI feeding an induction motor load is explained with necessary waveforms and phasor diagrams. The necessity of reactive compensation by the active filter connected at the motor terminal for the load commutation of the thyristors, is elaborated with the help of analytical equations and phasor diagrams. The requirement of harmonic compensation by the same active filter to achieve sinusoidal motor current and motor voltage, is also described. Finally, to achieve the aforementioned induction motor drive, the VA ratings of the active filter (VSI) and the CSI with respect to VA rating of the motor, are determined theoretically. The proposed drive scheme is simulated under idealized condition. Simulation results show good steady state and dynamic response of the drive system. Load commutation of the SCRs in the LCI and the sinusoidal profile of motor current and voltage, have been demonstrated. As in LCI fed synchronous motor drives, a special mode of operation is required to run up the induction motor from standstill. As the SCRs of the LCI are load commutated, they need motor terminal voltages for commutation. At standstill these voltages are zero. So, a starting strategy has been proposed and adopted to start the motor with the aid of the current controlled VSI to accelerate until the motor terminal voltages are high enough for the commutation of the SCRs in the LCI. The proposed drive is implemented on an experimental setup in the laboratory. The IGBT based three level diode clamped VSI has been fabricated following the design of the standard module in the laboratory. A generalized digital control platform is also developed using a TMS320F2407A DSP. Two, three phase thyristor bridges with necessary firing pulse circuits have been used as the phase controlled rectifier and the LCI respectively. Appropriate protection scheme for such a drive is developed and adopted to operate the drive. Relevant experimental results are presented. They are observed to be in good agreement with the simulation results. The effect of capacitors connected at the output of the LCI in the commutation process of the SCRs in the LCI is studied and analyzed. From the analysis, it is understood that the capacitors form a parallel resonating pair with filter inductor and the motor leakage inductance, which results in an undesired oscillation in the terminal voltage during each of the commutation intervals leading to commutation failure. So, in the final system, the capacitors are removed to eliminate any chance of commutation failure of the SCRs in the LCI. It is shown by experiment that the commutation of the SCRs takes place reliably in the absence of the capacitors also. The commutation process is studied and analyzed without the capacitors to understand the motor terminal voltage waveform of the experimental results.

This thesis deals with the real time dynamic system control and it uses similar computation methods as earlier bachelor thesis. In the beginning of the thesis, some basics from the field of control and regulation are explained. Systems in this thesis are mostly described by differential equations. Because of this, thesis contains a section about solving differential equations. In this section, multiple approaches are covered and compared. The Modern Taylor series method is introduced, which is used by implemented applications. For system simulation, existing software was upgraded and multiple additional utilities were also implemented. The approximation of the transport delay is also mentioned.

The primary aim of the research has been to determine whether there is a relationship between personality variables as measured by the Occupational Personality Questionnaire (OPQ32i) and the work performance of credit controllers in a bank. Work performance was measured by means of internal company data sources. A literature review was used to verify whether there is a theoretical relationship between personality and work performance and strong evidence was found. The sample consisted of 89 credit controllers. The relationship between personality variables and work performance was determined by means of correlation studies and multiple regression analyses. Results are reported both in terms of statistical significance and effect sizes. Key terms: personality, work performance, credit control, personality trait theory, Sixteen Personality Factors questionnaire (16PF), Occupational Personality Questionnaire (OPQ). / Industrial and Organizational Psychology / M.Com. (Industrial Psychology)