Engineering Commons^™

Radiometric Correction Of Multispectral Cameras Using Photosensor Irradiance For Agronomy Applications, Nicholas S. Mitchell

Electronic Thesis and Dissertation Repository

Cloud coverage has a significant impact on the reflectance maps generated by multispectral cameras mounted on UAV's in small farm settings. The current approach is to calibrate the camera once before every flight and use the radiometric calibration map for the entire flight. In this work we have designed and built a downwelling and upwelling photosensor to work in sync with our custom multispectral camera. A dual reflectance panel implementation for the time dependent radiometric calibration of the multispectral camera is completed. The solar spectral irradiance curve is approximated using the current measurements from the downwelling photosensor and the ground …

Efficient Hardware Architectures For Public-Key Cryptosystems, Mohammadamin Saburruhmonfared

Electronic Thesis and Dissertation Repository

Finite field arithmetic plays an essential role in public-key cryptography as all the underlying operations are performed in these fields. The finite fields are either prime fields or binary fields. Binary field elements can mainly be represented on a polynomial basis or a normal basis (NB). NB representation offers a simple squaring operation, especially in hardware. However, multiplication is typically complex, and a particular subset of NB called Gaussian Normal Basis (GNB) features an efficient multiplication operation used in this work. The first part of this thesis has focused on improving finite field arithmetic architectures over GNB. Among different arithmetic …

Towards Efficient And Secure Iiot: Solutions For The Sensing Domain, Elena Uchiteleva

Electronic Thesis and Dissertation Repository

This work explores reduced complexity solutions for the increased efficiency and safety of the industrial Internet of Things (IIoT) sensing domain. Resource virtualization, security, and predictive modeling are the main subjects of these studies.

The first solution is a joint throughput and time-resource allocation scheme for virtualization of IEEE 802.15.4-based wireless sensor networks. Virtualization is realized through the utilization of the guaranteed time slot mechanism for scheduling on the medium access control (MAC) layer. The solution abstracts resources into logical units that are allocated to segregated applications with different service requirements. The problem is formulated in a linear optimization framework …

Longitudinal Partitioning Waveform Relaxation Methods For The Analysis Of Transmission Line Circuits, Tarik Menkad

Electronic Thesis and Dissertation Repository

Three research projects are presented in this manuscript. Projects one and two describe two waveform relaxation algorithms (WR) with longitudinal partitioning for the time-domain analysis of transmission line circuits. Project three presents theoretical results about the convergence of WR for chains of general circuits.

The first WR algorithm uses a assignment-partition procedure that relies on inserting external series combinations of positive and negative resistances into the circuit to control the speed of convergence of the algorithm. The convergence of the subsequent WR method is examined, and fast convergence is cast as a generic optimization problem in the frequency-domain. An automatic …

An Investigation Of The Interleaved Operation Of A Stacked Ac-Dc Single-Stage Flyback Converter, Mengkai Xiong

Electronic Thesis and Dissertation Repository

Low power AC-DC power conversion is typically done with a two-stage converter that consists of an AC-DC front-end boost converter that also performs input power factor correction and an isolated DC-DC back-end converter that is either a flyback or a forward converter. In applications where cost is an overriding factor, single-stage AC-DC converters that use a single power converter to simultaneously perform input power factor correction and AC-DC conversion can be used. In applications where output filtering and hold-up time are important considerations, single-stage AC-DC converters are implemented with a DC bus capacitor.

The main objective of this thesis is …

Terramechanics And Machine Learning For The Characterization Of Terrain, Bryan W. Southwell

Electronic Thesis and Dissertation Repository

An instrumented rover wheel can collect vast amounts of data about a planetary surface. Planetary surfaces are changed by complex geological processes which can be better understood with an abundance of surface data and the use of terramechanics. Identifying terrain parameters such as cohesion and angle of friction hold importance for both the rover driver and the planetary scientist. Knowledge of terrain characteristics can warn of unsafe terrain and flag potential interesting scientific sites. The instrumented wheel in this research utilizes a pressure pad to sense load and sinkage, a string potentiometer to measure slip, and records motor current draw. …

Advanced Hardware And Software Approach To Seismic Site Response Investigations, Aleksandar Dimitrov Mihaylov

Electronic Thesis and Dissertation Repository

Vibration measurement is an essential aspect of modern geotechnical engineering. It is particularly vital task for measuring the dynamic soil parameters, estimating seismic hazards and evaluating influence of industrial, traffic and construction vibrations on the surrounding buildings, structures and their elements. Meanwhile, commercial exploration seismic stations and data acquisition systems require significant professional knowledge and training in geophysics or vibration measurement, as well as practical skills and experience in adjusting data acquisition parameters. Furthermore, available seismological investigation and vibrometry sensors are not universally suitable for field applications in geophysical studies, soil-structure interaction investigations or structural vibrations. The frequency range suitable …