Development Of Dynamic Proof-Mass Configurations For Broadband Piezoelectric Energy Harvesting, Nico E. Galarza

Electrical and Computer Engineering ETDs

The purpose of this thesis is to investigate and develop dynamic proof-mass configurations for broadband piezoelectric energy harvesting. Conventional piezoelectric energy harvesters are typically limited by narrow operating bandwidths, restricting their performance under variable-frequency excitation. This research presents the design, fabrication, and experimental evaluation of multiple proof-mass concepts intended to increase the usable frequency range of cantilever-based piezoelectric energy harvesters. Several dynamic mass configurations were developed using additive manufacturing techniques and integrated with commercially available piezoelectric cantilevers. Experimental testing was conducted under controlled vibration conditions to characterize voltage response, resonant behavior, and bandwidth performance. The results demonstrate that dynamic proof-masses …

“Bridging The Gap To Midwave Infrared Event-Based Sensors: Design, Sensitivity, And Radiation-Hardness Characterization Of A Single-Pixel Iii-V Event-Based Infrared Sensor For Space Applications, Zinah M. Alsaad

Electrical and Computer Engineering ETDs

Event-based sensing presents a revolutionary paradigm shift for next-generation space surveillance systems, where power consumption is an ever-worsening constraint as temporal resolution demands increase. In addition to reduced power consumption, low latency, and wide dynamic range, the event-based sensor fundamentally only produces data when there is a change in illumination from which events are generated; no data is produced if the scene remains static. With their event-based datastream being inherently focused on the dynamic information of the scene, they are particularly well-suited to machine vision and autonomous sensing applications. While these sensors have many compelling advantages, there are presently no …

Design Of A Subthreshold Cmos Inverter-Based Amplifier For Low-Noise And Low-Power Applications, Landon Alexander Schmucker

Electrical and Computer Engineering ETDs

Amplification is a fundamental function in most analog circuits. There is a fast-growing demand for low-power, low-noise, and high-gain amplifiers. Modern semiconductor processes are increasingly optimized for digital applications, which has introduced new challenges in analog design. To address these challenges, analog designers have investigated replacing conventional analog circuits with digital implementations. One promising application is the typical CMOS inverter as an amplifier.

This research presents a CMOS inverter-based amplifier with feedback designed to achieve low power consumption, low input noise, and high gain. Unlike typical CMOS inverter-based amplifiers, this topology has two distinctive features: (1) it uses a MOSFET …

A Dynamically Efficient Predictive Controller For Voltage Stability In A Dc To Dc Boost Converter, Giovanni Reyna

Electrical and Computer Engineering ETDs

Reliable voltage regulation has become a critical issue with increase demand in modern power electronic applications. This study presents a Model Predictive Controller (MPC) for voltage regulation in DC-to-DC boost converters. A closed loop analytical MPC framework is created with the purpose of computing optimal duty cycles to maintain a stable output voltage under varying load conditions, input changes, and disturbances.

To evaluate the performance of the MPC we set the controller against a comparative analyzing with a traditional cascading proportional integral (PI) controller. The proposed controller design is specifically targeted to improve dynamic efficiency during the converter’s transient events. …

Design And Characterization Of Radiation-Hardened Gaas Hbt-Based Optical Transceivers, Collin Burt

Electrical and Computer Engineering ETDs

Optical transceivers are desirable for their galvanic isolation and natural immunity to electromagnetic interference compared with direct electrical connections. This is true in normal operating environments as well as radiation environments. This work realizes and characterizes GaAs HBT-based optical transceivers across temperature and a range of radiation environments including high dose rate, total ionizing dose, neutron, and heavy ion. The transceiver designs are discussed and specific environmental design considerations are highlighted. Final results for each environment are provided and compared with existing transceivers.

Design, Fabrication And Characterization Of Zero Power Sensor/Harvester For Smart Grid Applications, Zeynel Guler

Mechanical Engineering ETDs

This study presents a flexible sensor/harvester device to be used in both electromagnetic sensing and energy harvesting applications for smart grids. When a current passes through a wire, the sensor detects the magnetic field created by that current. The sensor magnet interacts with the wire magnetic field resulting in a transfer of energy through the piezoelectric cantilever. Piezoelectric, conductive, magnetic, and magnetostrictive composite thin films were prepared to fabricate this device.

Initially, the magnet of the cantilever was optimized considering its shape, thickness, length, taper angle etc. via both simulations and experiments. Peak to peak voltage versus cantilever position graph …

Modeling And Characterization Of Cmos Logic Gates Under Large Signal Rf Injection, Zahra Abedi

Electrical and Computer Engineering ETDs

This research addresses the issue of electromagnetic interference (EMI) in digital electronics, which can cause undesired behavior in active electronic components and systems. As technology advances and transistor size decreases, devices become more susceptible to EMI. In addition, as voltage is scaled down to save energy, silicon chips become more susceptible to soft errors. While there are several ways to mitigate the impact of severe EMI on digital systems, minimal electromagnetic coupling can still cause significant problems. We develop analytical models to predict device upset due to EMI. The study focuses on identifying vulnerable parameters of operation related to device …

Vi Energy-Efficient Memristor-Based Neuromorphic Computing Circuits And Systems For Radiation Detection Applications, Jorge Iván Canales Verdial

Electrical and Computer Engineering ETDs

Radionuclide spectroscopic sensor data is analyzed with minimal power consumption through the use of neuromorphic computing architectures. Memristor crossbars are harnessed as the computational substrate in this non-conventional computing platform and integrated with CMOS-based neurons to mimic the computational dynamics observed in the mammalian brain’s visual cortex. Functional prototypes using spiking sparse locally competitive approximations are presented. The architectures are evaluated for classification accuracy and energy efficiency. The proposed systems achieve a 90% true positive accuracy with a high-resolution detector and 86% with a low-resolution detector.

Evaluation Of The Dynamic Vision Sensor’S Photoreceptor Circuit For Infrared Event-Based Sensing, Zinah M. Alsaad

Electrical and Computer Engineering ETDs

For space surveillance applications, neuromorphic imaging is being studied as it may perform sensing and tracking tasks with less power and downstream datalink demand. The read-out of the event-based camera is made to only be sensitive to changes in the signals it receives from the photodetector, which results in a datastream of events indicating where and when changes in illumination occur. This is in contrast to the conventional framing camera, which produces images by essentially counting the electrons produced by light incident on each pixel’s photodetector. These cameras are commercially available with siliconbased detectors for applications involving visible wavelengths. However, …

Material Characterization And Comparison Of Sol-Gel Deposited And Rf Magnetron Deposited Lead Zirconate Titanate Thin Films, Katherine Lynne Miles

Mechanical Engineering ETDs

Lead zirconate titanate (PZT) has been a material of interest for sensor, actuator, and transducer applications in microelectromechanical systems (MEMS). This is due to their favorable piezoelectric, pyroelectric and ferroelectric properties. While various methods are available to deposit PZT thin films, radio frequency (RF) magnetron sputtering was selected to provide high quality PZT films with the added capability of batch processing. These sputter deposited PZT films were characterized to determine their internal film stress, Young’s modulus, composition, and structure. After characterization, the sputtered PZT samples were poled using corona poling and direct poling methods. As a means of comparison, commercially …

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 …

Side Channel Attack Counter Measure Using A Moving Target Architecture, Jithin Joseph

Electrical and Computer Engineering ETDs

A novel countermeasure to side-channel power analysis attacks called Side-channel Power analysis Resistance for Encryption Algorithms using DPR or SPREAD is investigated in this thesis. The countermeasure leverages a strategy that is best characterized as a moving target architecture. Modern field programmable gate arrays (FPGA) architectures provide support for dynamic partial reconfiguration (DPR), a feature that allows real-time reconfiguration of the programmable logic (PL). The moving target architecture proposed in this work leverages DPR to implement a power analysis countermeasure to side-channel attacks, the most common of which are referred to as differential power analysis (DPA) and correlation power analysis …

Computational_Electromagnetic Modeling (Cem) Of Foliage Penetration (Fopen), Monica R. Jaramillo

Electrical and Computer Engineering ETDs

Foliage penetration (FOPEN) radar at lower frequencies (UHF, VHF) is a well-studied area with a wide set of contributions. However, there is growing interest in using higher Ku-band frequencies (12-18 GHz frequency range) for FOPEN. In particular, the reduced wavelength sizes (centimeters range) provide some key saliencies for developing more optimized foliage detection solutions. The disadvantage is that exploiting Ku-band for FOPEN is complicated because higher frequencies have much more pronounced scattering effects due to their smaller wavelengths. Despite these challenges, certain foliage characteristics and signal parameters can help improve electromagnetic (EM) wave penetration in the Ku-band such as foliage …

Experimental Investigation Of The Wind Energy Harvesting Potential Of A Stand-Alone Piezoelectric Strip, Phillip Christopher Scott

Mechanical Engineering ETDs

The purpose of the study was to investigate the feasibility of harvesting wind energy on a small scale in residential areas. The method investigated was the initiation of movement-induced excitation (MIE), a type of aeroelastic flutter, within samples of polyvinylidine fluoride (PVDF), a piezoelectric polymer. Single samples of PVDF were secured in a wind tunnel and sample voltage was measured over a broad range of wind speeds. Power was calculated then via the addition of ohmic resistance matched to the magnitude of the capacitive impedances of the samples. The geometry of the PVDF samples studied was maintained as a simple …

Side-Channel Power Resistance For Encryption Algorithms Using Implementation Diversity, Ivan M. Bow

Electrical and Computer Engineering ETDs

This thesis paper investigates countermeasures to hardware side-channel attacks and proposes a new solution to this ever growing threat against data integrity and security. The side-channel attack methods, differential power analysis and correlation power analysis, are both very powerful techniques and are used to gain access to secrets inside of a field programmable gate array that are otherwise inaccessible, in particular the cryptographic key for the Advanced Encryption Standard algorithm. To counter these attacks, we propose a method of changing the internal hardware configuration of the field programmable gate array using dynamic partial reconfiguration. Using this method, we change the …

Nonlinear Least Squares 3-D Geolocation Solutions Using Time Differences Of Arrival, Michael V. Bredemann

Mathematics & Statistics ETDs

This thesis uses a geometric approach to derive and solve nonlinear least squares minimization problems to geolocate a signal source in three dimensions using time differences of arrival at multiple sensor locations. There is no restriction on the maximum number of sensors used. Residual errors reach the numerical limits of machine precision. Symmetric sensor orientations are found that prevent closed form solutions of source locations lying within the null space. Maximum uncertainties in relative sensor positions and time difference of arrivals, required to locate a source within a maximum specified error, are found from these results. Examples illustrate potential requirements …

Improvement Of The Material’S Mechanical Characteristics Using Intelligent Real Time Control Interfaces In Hfc Hardening Process, Florentin Smarandache, Luige Vladareanu, Mihaiela Iliescu, Victor Vladareanu, Alexandru Gal, Octavian Melinte, Adrian Margean

Branch Mathematics and Statistics Faculty and Staff Publications

The paper presents Intelligent Control (IC) Interfaces for real time control of mechatronic systems applied to Hardening Process Control (HPC) in order to improvement of the material’s mechanical characteristics. Implementation of IC laws in the intelligent real time control interfaces depends on the particular circumstances of the models characteristics used and the exact definition of optimization problem. The results led to the development of the IC interfaces in real time through Particle Swarm Optimization (PSO) and neural networks (NN) using off- line the regression methods.

Noise And Gain Characterization Of Interband Cascade Infrared Photodetectors, Eli A. Garduño

Electrical and Computer Engineering ETDs

Infrared (IR) detectors are an enabling technology for a broad and growing list of applications including gas detection, night vision, and space-based missile warning. There are ongoing efforts in IR detector research to explore the potential of new material systems and energy band structures in addition to continuously improving their sensitivity through increasing their quantum efficiency and lowering their dark current and noise. This dissertation examines an emerging class of IR detectors known as Interband Cascade Infrared Photodetectors (ICIPs).

ICIPs contain multiple regions to facilitate the collection of photogenerated electrons and to limit unwanted dark current. Theory regarding their performance …

Capacitive Pcb Security For Active Tamper And Alteration Detection, Casey Petersen

Electrical and Computer Engineering ETDs

The purpose of the research presented is to establish the viability of using capacitive based sensors for the purpose of hardware security at the Printed Circuit Board (PCB) level. Capacitive sensors are traditionally used to sense changes to the areas surrounding the sensing pads in applications such as sensing proximity, position, humidity, fluid levels and much more.

The specific sensor used for this research is an inductor-capacitor (LC) based Capacitance-to-Digital Converter. This configuration is virtually immune to EM noise because it is a tank circuit and therefore filters out the noise which, in the past, caused reliability issues with these …

Some Aggregation Operators For Bipolar-Valued Hesitant Fuzzy Information, Florentin Smarandache, Tahir Mahmood, Kifayat Ullah, Qaisar Khan

Branch Mathematics and Statistics Faculty and Staff Publications

In this article we define some aggregation operators for bipolar-valued hesitant fuzzy sets. These operations include bipolar-valued hesitant fuzzy ordered weighted averaging (BPVHFOWA) operator, bipolar-valued hesitant fuzzy ordered weighted geometric (BPVHFOWG) operator and their generalized forms. We also define hybrid aggregation operators and their generalized forms and solved a decision-making problem on these operation.

Investigating Scalable Manufacturing Of High-Conductivity Wires And Coatings From Ultra-Long Carbon Nanotubes, Pouria Khanbolouki

Mechanical Engineering ETDs

Carbon nanotubes (CNTs) are a promising candidate for next generation of electrical wirings and electromagnetic interference (EMI) shielding materials due to their exceptional mechanical and electrical properties. Wires and coatings from ultralong nanotubes that are highly crystalline, well-aligned and densely packed can achieve this goal. High-performance CNT conductors will be relatively lightweight and resistant to harsh conditions and therefore can potentially replace current conductors in many industries including aerospace, automotive, gas and oil.

This thesis investigates a new manufacturing approach, based on conventional solution coating and wire drawing methods, to fabricate high conductivity wires and coatings from ultra-long carbon nanotubes. …

Design & Evaluation Of A Hybrid Switched Capacitor Circuit With Wide-Bandgap Devices For Dc Grid Applications, Joshua L. Stewart

Electrical and Computer Engineering ETDs

ABSTRACT

As technologies advance, the rate at which renewable power sources, such as solar photovoltaic (PV) and wind, are being added to the power grid is increasing. Typically, PV power plants require large inverters for direct current to alternating current (DC-AC) power conversion, as well as large transformers to step up voltages to the grid voltage. Offshore wind farms and large PV power plants in remote locations often aggregate power on a DC bus in order to improve efficiency and reduce the cost of power conversion hardware within the energy complex. However, the power must still be converted to AC …

Investigating The Classical And Non-Classical Mechanical Properties Of Gan Nanowires, Mohammad Reza Zamani Kouhpanji

Electrical and Computer Engineering ETDs

Study and prediction of classical and non-classical mechanical properties of GaN is crucial due to the potential application of GaN nanowires (NWs) in piezoelectric, probe-based nanometrology, and nanolithography areas. GaN is mainly grown on sapphire substrates whose lattice constant and thermal expansion coefficient are significantly different from GaN. These discrepancies cause mechanical defects and high residual stresses and strains in GaN, which reduce its quantum efficiency.

Specifically, for nanoscale applications, the mechanical properties of materials differ significantly compared to the bulk properties due to size-effects. Therefore, it is essential to investigate the mechanical properties of GaN NWs using the non-classical …

The Effect Of Power Supply Ramp Time On Sram Puf's, Abdelrahman T. Elshafiey Mr.

Electrical and Computer Engineering ETDs

Physical unclonable functions (PUFs) are security primitives that exploit the device mismatches. PUFs are a promising solution for hardware cryptography and key storage. They are used in many security applications including identification, authentication and key generation. SRAM is one of the popular implementations of PUFs. SRAM PUFs offer the advantage, over other PUF constructions, of reusing resources (memories) that already exist in many designs.

In this thesis, for the first time, it is demonstrated that the start-up value of an SRAM PUF could be different depending on the SRAM power supply rising time. An analytical model has been developed to …

Measurement And Analysis Of Iii-V & Ii-Vi Infrared Detectors: Radiometric, Noise Spectrum, And Radiation Tolerance Performance, Vincent M. Cowan

Nanoscience and Microsystems ETDs

Infrared (IR) hybrid detector arrays and discrete detectors operated in the space environment may be subjected to a variety of sources of natural radiation while in orbit. This means IR detectors intended for applications such as space-based intelligence, surveillance, and reconnaissance (ISR) or space-situational awareness (SSA) must not only have high performance (high quantum efficiency, h and low dark-current density, J_D, and preferably minimal 1/f noise content), but also their radiation tolerance or ability to withstand the effects of the radiation they would expect to encounter in space must be characterized and well understood. As the effects of …

Plains Electric Members Service Area_04-29-1994, University Of New Mexico Bureau Of Business And Economic Research

BBER Publications

This report presents historical and projected socioeconomic data for 19 New Mexico and two Arizona counties which comprise the service areas of the distribution cooperatives in the Plains Electric Generation and Transmission Cooperative, Inc., system.

Transistorized Circuits For Telemetry, Dominick Misciascio Jr.

Physics & Astronomy ETDs

This thesis is concerned with the telemetry of small DC signals from photomultiplier tubes. The circuitry must have a high input impedance so as not to load down the photomultiplier tube and a low output impedance which is capable of controlling the current through a small incandescent bulb. This bulb is used to illuminate a photoresistor. The output of the circuit consists of a variation of the resistance of the photoresistor. This variable resistance is conventionally converted into a variable audio frequency which is transmitted to the receiving station on a radio-frequency carrier. The output resistance must be independent of …