Engineering Commons^™

Wireless Coverage Using Unmanned Aerial Vehicles, Hazim Shakhatreh

Dissertations

The use of unmanned aerial vehicles (UAVs) is growing rapidly across many civilian application domains including real-time monitoring, search and rescue, and wireless coverage. UAVs can be used to provide wireless coverage during emergency cases where each UAV serves as an aerial wireless base station when the cellular network goes down. They can also be used to supplement the ground base station in order to provide better coverage and higher data rates for the users. During such situations, the UAVs need to return periodically to a charging station for recharging, due to their limited battery capacity. Given the recharging requirements, …

Impairments In Ground Moving Target Indicator (Gmti) Radar, Phuoc Doan Huu Vu

Dissertations

Radars on multiple distributed airborne or ground based moving platforms are of increasing interest, since they can be deployed in close proximity to the event under investigation and thus offer remarkable sensing opportunities. Ground moving target indicator (GMTI) detects and localizes moving targets in the presence of ground clutter and other interference sources. Space-time adaptive processing (STAP) implemented with antenna arrays has been a classical approach to clutter cancellation in airborne radar. One of the challenges with STAP is that the minimum detectable velocity (MDV) of targets is a function of the baseline of the antenna array: the larger the …

Optimizing Resource Allocation In Eh-Enabled Internet Of Things, Ali Shahini

Dissertations

Internet of Things (IoT) aims to bridge everyday physical objects via the Internet. Traditional energy-constrained wireless devices are powered by fixed energy sources like batteries, but they may require frequent battery replacements or recharging. Wireless Energy Harvesting (EH), as a promising solution, can potentially eliminate the need of recharging or replacing the batteries. Unlike other types of green energy sources, wireless EH does not depend on nature and is thus a reliable source of energy for charging devices. Meanwhile, the rapid growth of IoT devices and wireless applications is likely to demand for more operating frequency bands. Although the frequency …

Characterization Of Self-Heating Effects And Assessment Of Its Impact On Reliability In Finfet Technology, Peter Christopher Paliwoda

Dissertations

The systematically growing power (heat) dissipation in CMOS transistors with each successive technology node is reaching levels which could impact its reliable operation. The emergence of technologies such as bulk/SOI FinFETs has dramatically confined the heat in the device channel due to its vertical geometry and it is expected to further exacerbate with gate-all-around transistors.

This work studies heat generation in the channel of semiconductor devices and measures its dissipation by means of wafer level characterization and predictive thermal simulation. The experimental work is based on several existing device thermometry techniques to which additional layout improvements are made in state …

Load Balancing And Scalable Clos-Network Packet Switches, Oladele Theophilus Sule

Dissertations

In this dissertation three load-balancing Clos-network packet switches that attain 100% throughput and forward cells in sequence are introduced. The configuration schemes and the in-sequence forwarding mechanisms devised for these switches are also introduced. Also proposed is the use of matrix analysis as a tool for throughput analysis.

In Chapter 2, a configuration scheme for a load-balancing Clos-network packet switch that has split central modules and buffers in between the split modules is introduced. This switch is called split-central-buffered Load-Balancing Clos-network (LBC) switch and it is cell based. The switch has four stages, namely input, central-input, central-output, and output stages. …

Storage Systems For Mobile-Cloud Applications, Nafize R. Paiker

Dissertations

Mobile devices have become the major computing platform in todays world. However, some apps on mobile devices still suffer from insufficient computing and energy resources. A key solution is to offload resource-demanding computing tasks from mobile devices to the cloud. This leads to a scenario where computing tasks in the same application run concurrently on both the mobile device and the cloud.

This dissertation aims to ensure that the tasks in a mobile app that employs offloading can access and share files concurrently on the mobile and the cloud in a manner that is efficient, consistent, and transparent to locations. …

Vision-Based Framework For Monitoring Of Eating Behavior Of Persons With Alzheimer’S Disease, Haitham Al-Anssari

Dissertations

Dementia is a syndrome used to describe an array of significant declines in cognitive abilities due to progressive and irreversible loss of neurons and brain functioning. This neurodegeneration seriously affects daily life activities like driving, shopping, working and speaking. Among these, Alzheimer’s disease is the most common type of dementia, with individuals experiencing loss of memory and thinking and reasoning skills. Due to cognitive decline, individuals with Alzheimer’s often suffer from malnutrition, since they do not eat, even when food is presented, and must be fed with assistance. This assistance presents a significant burden of time to caregivers, and consequently …

Development And Characterization Of Nano Nickel-Based Conductive Inks For Flexographic Printing Of Electronics And New Interpretations Of Surface Energies Of Solids, Bilge Nazli Altay

Dissertations

Traditional printing technologies and conductive/functional inks have been integrated to print electronic devices and circuits on really think, lightweight and flexible materials in a time and cost-effective manner. Printing is an additive manufacturing technology, which selectively deposits materials only where needed to produce a wide range of devices including sensors, smart packaging, solar panels, batteries, light sources and wearable electronics. Therefore, it greatly reduces the number of required steps for manufacturing as well as the amount of waste generated relative to conventional electronic manufacturing. However, the process requirements and ink formulations to print electronics differ from graphic printing; therefore, the …

Integrated Compressive Sensing And Feature Descriptors- A Framework For Facial Recognition Systems, Ali Kadhem Jaber

Dissertations

Facial recognition is still a challenge in many applications, particularly in surveillance, security systems, and human-computer interactive (HCI) tools. The impact of real-world environmental variations on the performance of any facial recognition system can be significant. These variations may include illumination, facial expressions, poses, disguises (facial hair, glasses or cosmetics) and partial face occlusion. Furthermore, the number of images (samples) needed for facial recognition systems can be very large, much larger than what is typically required by an algorithm, and this is often made worse with expansion of the feature space dimensionality. Truly, the “curse of dimensionality” haunts any real-time …

Practical Vortex Beam Generation, Nedime Pelin Mohamed Hassan Salem

Dissertations

Vector vortex beams are monochromatic electromagnetic wave fields carrying spin angular momentum (SAM) and orbital angular momentum (OAM). Spin angular momentum is associated with the polarization of the field, whereas OAM yields an azimuthal field dependence of the form exp( jqφ), where φ is the azimuthal angle, and q is an integer designating the helicity order, which is also known as the topological charge of the vortex beam. Vortex beams owe their names to the characteristic on-axis phase singularity and amplitude null.

In this study, a new method to generate vector vortex beams in the microwave regime is devised …

Optimized Insulation And Filter Design Of Rotating Machines Fed By Fast Front Pulses, Mohammed Khalil Hussain

Dissertations

AC rotating machines are exposed to fast front pulses when fed from inverters. This type of excitation produces dielectric stress in the machine’s insulation system that can result in premature deterioration or even failure.

In this dissertation, a non-uniform transmission line model to predict the transient voltage distribution in a machine coil under steep-fronted surge conditions is described and implemented. This model is a function not only of frequency but also of space to represent the variation of electrical parameters in the overhang and slot regions of the coil. These parameters are computed using the finite element method. In order …

Online Edge Caching And Wireless Delivery In Fog-Aided Networks, Seyyed Mohammadreza Azimi

Dissertations

Multimedia content is the significant fraction of transferred data over the wireless medium in the modern cellular and wireless communication networks. To improve the quality of experience perceived by users, one promising solution is to push the most popular contents as close as to users, also known as the "edge" of network. Storing content at the edge nodes (ENs) or base stations (BSs) is called "caching". In Fog Radio Access Network (F-RAN), each EN is equipped with a cache as well as a "fronthaul" connection to the content server. Among the new design problems raised by the outlined scenarios, two …

Borehole Communication Via Drill Strings In Oil Wells, Ali Hamdan Alenezi

Dissertations

The performance of multichannel and single channel accelerometers used as uphole communication receivers is studied. Using measured channels from the drill string testbed, it is shown that one tri-axial accelerometer can provide nearly uncorrelated signals when compared to two single channel accelerometers. Having uncorrelated signals at the uphole receiver provides a diversity which in turn can lead to an increase in the communication system performance. The use of a strain sensor as a receiver in borehole communication is proposed. Using measured channels from the drill string testbed, the performance of a strain receiver with a single-accelerometer receiver is compared. The …

Secure Entity Authentication, Zuochao Dou

Dissertations

According to Wikipedia, authentication is the act of confirming the truth of an attribute of a single piece of a datum claimed true by an entity. Specifically, entity authentication is the process by which an agent in a distributed system gains confidence in the identity of a communicating partner (Bellare et al.). Legacy password authentication is still the most popular one, however, it suffers from many limitations, such as hacking through social engineering techniques, dictionary attack or database leak. To address the security concerns in legacy password-based authentication, many new authentication factors are introduced, such as PINs (Personal Identification Numbers) …

From Geographically Dispersed Data Centers Towards Hierarchical Edge Computing, Abbas Kiani

Dissertations

Internet scale data centers are generally dispersed in different geographical regions. While the main goal of deploying the geographically dispersed data centers is to provide redundancy, scalability and high availability, the geographic dispersity provides another opportunity for efficient employment of global resources, e.g., utilizing price-diversity in electricity markets or utilizing locational diversity in renewable power generation. In other words, an efficient approach for geographical load balancing (GLB) across geo-dispersed data centers not only can maximize the utilization of green energy but also can minimize the cost of electricity. However, due to the different costs and disparate environmental impacts of the …

On Distributed Mobile Edge Computing, Xiang Sun

Dissertations

Mobile Cloud Computing (MCC) has been proposed to offload the workloads of mobile applications from mobile devices to the cloud in order to not only reduce energy consumption of mobile devices but also accelerate the execution of mobile applications. Owing to the long End-to-End (E2E) delay between mobile devices and the cloud, offloading the workloads of many interactive mobile applications to the cloud may not be suitable. That is, these mobile applications require a huge amount of computing resources to process their workloads as well as a low E2E delay between mobile devices and computing resources, which cannot be satisfied …

Microfluidic Biosensor With Functionalized Gold Nano Particles On Interdigitated Electrodes, Bharath Babu Nunna

Dissertations

The integration of the microfluidics to the biosensor has growing demand with favorable conditions such as reduced processing time and low reagent consumption. The immuno biosensing with the microfluidic platform helped to make the electrochemical biosensing assays portable due to which this sensing mechanism can be easily implemented in point of care devices. The implementation of the biosensing in the microchannels significantly reduces the sample requirement form milli liter (mL) to micro liter (uL), and thus leads to low volume sample requirement during the sensing. The primary factors contributing to the microfluidic biosensors performance are probe immobilization, specific binding and …