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Full-Text Articles in Engineering
Machine Learning Approaches For Early Prediction Of Hypertension., Heba Elsayed Mohamed Kandil
Machine Learning Approaches For Early Prediction Of Hypertension., Heba Elsayed Mohamed Kandil
Electronic Theses and Dissertations
Hypertension afflicts one in every three adults and is a leading cause of mortality in 516, 955 patients in USA. The chronic elevation of cerebral perfusion pressure (CPP) changes the cerebrovasculature of the brain and disrupts its vasoregulation mechanisms. Reported correlations between changes in smaller cerebrovascular vessels and hypertension may be used to diagnose hypertension in its early stages, 10-15 years before the appearance of symptoms such as cognitive impairment and memory loss. Specifically, recent studies hypothesized that changes in the cerebrovasculature and CPP precede the systemic elevation of blood pressure. Currently, sphygmomanometers are used to measure repeated brachial artery …
Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya
Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya
Mechanical Engineering ETDs
Fast detection and isolation of faults in a DC microgrid is of particular importance. Fast tripping protection (i) increases the lifetime of power electronics (PE) switches by avoiding high fault current magnitudes and (ii) enhances the controllability of PE converters. This thesis proposes a traveling wave (TW) based scheme for fast tripping protection of DC microgrids. The proposed scheme utilizes a discrete wavelet transform (DWT) to calculate the high-frequency components of DC fault currents. Multiresolution analysis (MRA) using DWT is utilized to detect TW components for different frequency ranges. The Parseval energy calculated from the MRA coefficients are then used …
Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya
Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya
Mechanical Engineering ETDs
Fast detection and isolation of faults in a DC microgrid is of particular importance. Fast tripping protection (i) increases the lifetime of power electronics (PE) switches by avoiding high fault current magnitudes and (ii) enhances the controllability of PE converters. This thesis proposes a traveling wave (TW) based scheme for fast tripping protection of DC microgrids. The proposed scheme utilizes a discrete wavelet transform (DWT) to calculate the high-frequency components of DC fault currents. Multiresolution analysis (MRA) using DWT is utilized to detect TW components for different frequency ranges. The Parseval energy calculated from the MRA coefficients are then used …
Investigation Of Graphene Interconnections For Multifunctional Reconfigurable Antenna Beam Steering, Joshua R. Perkins
Investigation Of Graphene Interconnections For Multifunctional Reconfigurable Antenna Beam Steering, Joshua R. Perkins
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In high frequency, high-performance wireless communications, direct line of sight antennas are common. The issue with the line of sight antennas is the need to redirect the physical antenna to achieve the best possible reception. Classical redirections are done by mechanical movements: hand tuning and motors. Our multi-functional re-configurable antenna (MRA) concept allows for electrical and non-mechanical antenna reorientation. This work investigates two important concepts in the development and enhancement of future MRA devices: special, non-interfering, control signal circuitry and nano-sized switching devices that are controlled by the special circuitry. The investigation was conducted with the use of commercially available …
Efficient Algorithms For Reconfigurable Antenna Systems, Mehedi Hasan
Efficient Algorithms For Reconfigurable Antenna Systems, Mehedi Hasan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The main goal of this research is to develop algorithms to facilitate the use of a new type of antenna, called multifunctional reconfigurable antenna (MRA). Traditional antennas have fixed radiation properties which cannot be changed to adapt to different environments. To solve this problem, MRAs, which can dynamically change its operation frequency, radiation patter, and polarization, has gained a significant interest recently. Such antennas can support multiple radio access technologies with different sets of operational requirements. Reconfigurable antennas are considered smart antennas. The efficient use of smart antennas requires efficient and smart underlying algorithms. This dissertation focuses on developing efficient …