In this dissertation, we explored multiple coding techniques to reduce energy consumption, improve performance, and secure wireless sensor networks specifically and ad-hoc networks in general. With the introduction of Internet of Things (IoT) and 5G technologies, wireless sensor networks are quickly emerging as an important and key technology in the...
Ring amplifiers (ringamps) have shown excellent power efficiency in the latest state-of-the-art analog to digital converters (ADCs). This thesis describes circuit techniques to ensure robust operation of ringamps using standard analog techniques and proportional-integral-derivative(PID) controller analogy. Large-signal and small-signal analysis of a ringamp are performed using simple RC settling and...
This research focuses on receiver architectures which enable better spectral eciency
by handling blockers in the same spectral range as the signal. The presence of
such blockers, without the use of blocker cancelling/ ltering techniques leads to gain
compression and hence, consequent performance degradation of receivers leading to
reduced spectrum...
In this thesis, we propose a Blockchain-based distributed protocol for enabling deployment of dynamic, on-demand IoT networks. Specifically, the proposed protocol leverages Blockchain technology to: (i) enable distributed and secure authentication, registration, and management of IoT devices; (ii) provide fast discovery of IoT resources and scalable and secure instantiation of...
Modern sensor network applications are often implemented wirelessly in order to lessen installation costs and reduce deployment times. Unfortunately, these wireless sensor network (WSN) nodes must often rely on batteries or energy harvesting techniques in order to sustain their operation and supply the power needed to maintain communication within the...
Inorganic structures play an important role in materials due to their versatility and diversity. A complete understanding of the structure of a material is vital to enhance the creation of new materials that fill voids in research. The rational design of these compounds is driven by the exploitation of structure-property...
Analog-to-digital converters are essential components to the portable devices that we are using today. Wireless sensors, body implanted devices, communication devices and so forth require low power ADCs. Therefore achieving higher resolution and bandwidth with lower power consumption is targeted in ADCs design. In this work power efficient ADCs for...
Generalisation is a key component of mathematical activity. Mathematicians often seek general formulae or wonder if a rule that holds in a particular dimension also holds in dimension n. However, generalisation is not limited to professional mathematicians; kindergarteners engage in generalisation when they seek patterns and algebra is sometimes described...
Today nano scale materials are being used for wide range of applications. One promising topic in nano scale materials is using them for reinforcement of different polymeric materials to reach desirable stiffness properties. The stiffness of these materials is mostly found experimentally because the nanocomposite community lacks a decent analytical...
The metal-organic–framework MOF-5 is used as an adsorbent in advanced systems for vehicular hydrogen storage that are currently under development. Presently, these systems are limited by poor thermal conductivity of the adsorption bed, and thus our research addresses how the interfaces between grains of MOF-5 can be engineered to improve...
In this dissertation, I describe the experimental investigation of catching ions in superfluid helium droplets. The ultimate goal of our project is to build a coherent electron diffraction apparatus for atomic structure determination from oriented single macromolecules. This involves generating protein ions from electrospray ionization (ESI) and doping them in...
The design and analysis of single point power-mooring cables applied to wave energy converters (WECs) is presented. WECs are mechanical devices designed and deployed to extract energy from waves in varying ways, and at varying distances from the shoreline. WEC devices operating on the water surface require mooring lines or...
The role of A-site non-stoichiometry was investigated in lead-free piezoelectric ceramics based on compositions in the 1-x(Bi₀.₅Na₀.₅TiO₃)-xBaTiO₃ system near the morphotropic phase boundary where x = 0.055, 0.06 and 0.07. The samples were prepared by a conventional solid state mixed oxide route with the A- site stoichiometry modified to incorporate...
The mechanical performance of composite materials is determined by the mechanical properties of their individual components and the effective load transfer between these components. Binders are commonly used to bond composite components together and to provide effective load transfer between them. In wood-based composites the binder-component load transfer occurs at...
Dental resin composites are widely used in modern dentistry due to their aesthetic appearance. However, resin based restorations have inferior mechanical properties (fracture is the second reason for restorations replacement) in comparison to alloy based composites and their antimicrobial properties still remain poor, leading to secondary tooth decay development on...
Manuscript I: The removal of residual casting material from gating has traditionally been performed by abrasive grinding techniques. However, high amounts of belt wear can occur when working with high strength alloys, especially those typically seen in the aerospace industry. An alternative machining process called electrochemical machining (ECM) uses electrolysis...
Whale blubber is the insular tissue layer located between the dermis and the superficial fascia layer which sheathes the whale's musculature. It is made up of a lipid matrix ramified with strong, structural collagen and elastic fiber bundles, but little is known of its mechanical properties. Knowing these properties adds...
Prior to eruption at mid-ocean ridges, melts must travel through >6 km of crust from their origin in the mantle. The final composition of the melts is dependent on both the melting conditions and magmatic processes within the crust. While mid-ocean ridge basalt (MORB) glasses are commonly used to infer...
Carbon nanotubes (CNTs) superior mechanical, electrical and thermal properties make them attractive components in nanomechanical devices. Their large aspect ratio and low density makes them ideal candidates for high frequency resonators in numerous applications including wireless communication, and mass and chemical sensors. One reason why CNTs have been slow to...
The variable output of renewables such as wind and solar causes fluctuations of power flow that can adversely affect power system operation, especially at high levels of penetration. The coordination of multiple energy storage solutions can mitigate integration challenges by providing a buffer from variable renewables. This thesis presents the...
The objective of this project is to demonstrate the feasibility fiber-reinforced turbine components through a design and manufacturing study. The motivation for using composites is to reduce weight and simplify manufacturing especially at high production volumes. In addition, natural fiber composites are implemented for applicable components to reduce environmental impact....
Phase Locked Loops(PLLs) are an integral part of almost every electronic system. Systems involving low frequency clocks often require PLLs with low bandwidth. The area occupied by the large loop filter capacitor and resistor in a low bandwidth PLL design makes the realization of traditional charge-pump PLL architecture impractical on...
Favorable properties of Balsa wood make it an interesting alternative in a number of
applications including thermal insulation or as a lightweight core material in
sandwich composites. Increasing use in construction necessitates a better
understanding of its mechanical and failure properties. In the present work, mode I
and mode II...
In this work, Neutron Depth Profiling (NDP) analysis capability has been added to the Oregon State University TRIGA® Reactor Prompt Gamma Neutron Activation Analysis Facility (PGNAA). This system has been implemented with an advanced digital spectroscopy system and is capable of rise time pulse shape analysis as well as coincidence...
Delta-sigma analog-to-digital converters traditionally have been used for low speed, high resolution applications such as measurements, sensors, voice and audio systems. Through continued device scaling in CMOS technology and architectural and circuit level design innovations, they have even become popular for wideband, high dynamic range applications such as wired and...
Low power, high speed serial transceivers are employed in a wide range of applications ranging from chip-to-chip, backplane, and optical interconnects. Apart
from being capable of handling a wide range of data rates, the transceivers should
have low power consumption (mW/Gbps) and be fully integrated. This work
discusses enabling techniques...
Pb(Zr,Ti)O₃ (PZT) is a very attractive material for use in piezoelectric-based microelectromechanical systems (MEMS) due to its high piezoelectric coefficients and ability for large displacements with relatively low applied fields (as compared to electrostatic-based MEMS). The piezoelectric effect is strongly anisotropic, thus it is very desirable to control the crystallographic...
The context of this thesis is a research project focused on the investigation of a renewable biopolymer-poly(lactic acid) (PLA) as a potential replacement of petroleum-based polymers in advanced nanocomposites reinforced with Microfibrillated cellulose (MFC). MFC is extracted from wood, which is a renewable, sustainable, carbon neutral and recyclable material. This...
As CMOS processes size continues to shrink, a number of factors limit the ability of analog circuit performance to scale with the process. These issues include smaller transistor intrinsic gains and lower supply voltages. However, scaling continues to increase the speed and decrease the power of digital circuits. In this...
The purpose of this study is to synthesize and characterize the nanoporous structures that can be obtained by the anodization of thin film aluminum sputter deposited on a silicon wafer substrate. This study also investigated the application of nanoporous alumina to fabricate nanorod arrays by using preceramic polymers. Although there...
Oil drilling requires that miles of steel drill pipe, called the drill string, be exposed to fatigue loading and corrosive environments. Furthermore, it has been reported that pitting corrosion is responsible for initiating catastrophic drillstring failure. Pitting corrosion is responsible for initiating fatigue cracks, with pits acting as local stress...
Photovoltaic (PV) cells have long been an attractive alternative for the consumption of fossil fuels but current manufacturing practices suffer from poor energy efficiency, large carbon footprints, low material utilization, high processing temperatures and high solvent usage. A critical step in PV production is the deposition of CdS as a...
The next generation of high temperature structural alloys must exhibit exceptional resistance to fracture, creep, oxidation, and fatigue at high temperatures. Chromium is being considered due to its high melting point (>1800°C), relatively low density (~7.2 g/cc), high temperature strength, and oxidation resistance. Limiting the use of chromium is its...
The development of microfluidic devices for heavy metal extraction is presented in this dissertation. Various research areas, covering subjects from photochromic compound syntheses to microchip fabrication techniques are explored to develop microfluidic devices capable of extracting heavy metal ions from drinking water. Through integration of the beneficial characteristics of both...
Customer requirements and engineering specifications will influence the direction of the design in any product, so it is crucial to make the requirements as stable as possible so quality designs can be produced on time within a budget. It would be optimal for requirements and specifications to remain constant but...
Currently, the temporal arc distribution across the ingot during the vacuum arc remelting (VAR) process is not a known or monitored parameter. It is has previously been shown that arcs can spatially constrict during VAR, and this constriction can lead to undesired defects in the material. Additionally, correct accounting for...
Azaspiracid has generated an enormous amount of scientific interest in the fourteen years since its initial discovery. The structure contains a 6,5,6 bis-spiroketal, a [3.3.1] bicyclic ketal and a 6,5-spiroaminal linkage as key moieties. With 9 rings, 20 stereocenters and three alkenes, the azaspiracid immediately attracted the interest of the...