Electrical and Computer Engineering Commons^™

The Performance And Power Impact Of Using Multiple Dram Address Mapping Schemes In Multicore Processors, Rami Jadaa

Electronic Theses and Dissertations

Lowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic mapping scheme over the fixed one. Results show that applications’ performance varies according to the mapping scheme used, and a dynamic mapping scheme achieves up to 2x …

Electromagnetic Propagation Anomalies In Waveguiding Structures And Scattering Systems, Alessandro Salandrino

Electronic Theses and Dissertations

The effects related to diffraction and interference are ubiquitous in phenomena involving electromagnetic wave propagation, and are accurately predicted and described within the framework of classical electrodynamics. In the vast majority of the cases the qualitative features of the evolution of a propagating wave can be inferred even without detailed calculations. A field distribution will spread upon propagation, will accumulate phase along the direction of power flow, will exert mechanical forces upon scattering objects in the direction of propagation etc. When such predictions fail, counterintuitive effects and new functionalities can be engineered. In this work a series of exceptional cases …

Weak Gradient Inverse Scattering Solutions, Jonathan Blackledge

Conference papers

The paper briefly reviews formal methods and associated conditions for solving the forward and inverse Schrodinger ¨ scattering problem for a three-dimensional elastic scattering potential. These methods are based on an application of the Green’s function and are conditional upon the properties of the scattering potential, e.g. that the scattering potential is a ‘weak scatterer’. In this paper, we explore an alternative route to solving the problem which depends on properties imposed on the scattered wavefield rather than the scattering potential. In particular, we explore the case when the gradient of the scattered wavefield is weak relative to its frequency. …

Application Of Stochastic Diffusion For Hiding High Fidelity Encrypted Images, Jonathan Blackledge, Abdulrahman Al-Rawi

Articles

Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganography provides a potential solution to this issue by making the data imperceptible, the security of the hidden information being a threat only if its existence …

Magnetic Resonance Image Processing Using Levy Distributed Anisotropic Diffusion, Jonathan Blackledge, Matthew Blackledge

Conference papers

We consider the physical nature of the self-diffusion of water molecules in tissue and explore how (Nuclear) Magnetic Resonance (MR) imaging may be used as a means of measuring the rate of diffusion in vivo. A discussion is presented on how these techniques may be implemented as a non-invasive means of assessing the response of tumours to novel therapeutics including some of the basic advantages and disadvantages when compared to other methods. The physical basis and mathematical models for diffusion are considered together with models for the distribution of the diffusion co-efficient including a Levy distributed model. Using a …

Hybrid Sensing And Adaptive Control For Direct Brain Actuation Of Artificial Limbs, Christopher Aasted

Electronic Theses and Dissertations

Developing a non-invasive direct brain control of artificial limbs is both challenging and desirable. Such a sensory and control system, if successful, will have a profound impact on the disabled. In this dissertation, we present the design and development of a non-invasive, hybrid sensory system, which uses near-infrared spectroscopy (NIRS) and electroencephalography (EEG) to measure brain activity with simultaneous electromyography (EMG) to provide feedback data in a healthy limb. Through the combination of these sensory techniques, we have successfully trained a control system capable of mapping brain activity onto muscle actuation. The design of a control algorithm capable of automatic …

Simulation, Application, And Resilience Of An Organic Neuromorphic Architecture, Made With Organic Bistable Devices And Organic Field Effect Transistors, Robert A. Nawrocki

Electronic Theses and Dissertations

This thesis presents work done simulating a type of organic neuromorphic architecture, modeled after Artificial Neural Network, and termed Synthetic Neural Network, or SNN. The first major contribution of this thesis is development of a single-transistor-single-organic-bistable-device-per-input circuit that approximates behavior of an artificial neuron. The efficacy of this design is validated by comparing the behavior of a single synthetic neuron to that of an artificial neuron as well as two examples involving a network of synthetic neurons. The analysis utilizes electrical characteristics of polymer electronic elements, namely Organic Bistable Device and Organic Field Effect Transistor, created in the laboratory at …

Dynamic Electrical Ratings And The Economics Of Capacity Factor For Wave Energy Converter Arrays, Fergus Sharkey, Elva Bannon, Michael Conlon, Kevin Gaughan

Conference papers

Wave Energy Converters (WECs) have been in development for several decades with some devices now coming close to commercial realities. As such, pilot projects are being developed, particularly in the UK and Ireland, to deploy WECs on a pre-commercial array scale. The ultimate ambition is to have multiple WECs installed in a ‘wave farm’ in a similar fashion to offshore wind farms. For large scale wind farms the inter-array and export electrical systems can represent more than 20% of the project’s capital expenditure. Submarine power cables account for a large proportion of this cost. The same is expected to hold …

Automated Detection Of Dust Clouds, Sources, And Direction From Noaa-Avhrr Satellite Imagery, Mohammed Qassim Alkhatib

Open Access Theses & Dissertations

This research is mainly focused on automatically locating dust sources and estimating their transport direction in NOAA-AVHRR images. Applications of AVHRR images may include agricultural assessment, producing maps of large area, and to retrieve various geophysical parameters. The AVHRR simultaneously records five bands of data, in our research, we focused on bands four and five since these wavelengths highlight the absorption and subsequent emission of thermal radiation by the silicate particles in the dust storms.

In this research, we propose a new method to detect dust clouds on satellite images. The approach we propose involves the use of an image …

Accelerated Simulation And Testing Of Integrated Circuits Using High Performance Computing Machines, Matthew C. Markulik

Open Access Theses & Dissertations

As Moore's Law continues to hold true and transistor density becomes exponentially larger the need to rely on computer aided design (CAD) simulators has become more relevant and necessary. As we dive into the age of electronic reliance there presents a need to constantly improve methods to reduce time-to-solution for developing technologies. The reliance on CAD simulators for electronic development leaves engineers with an ability to improve the design process by improving these simulators or improving the methods in which these simulators are being utilized. With the advancement of quality fabrication processes and the ability to operate at sub-threshold levels …

Pressure-Dependent Nanoheteroepitaxy Of Cdte On Si(100) And Soi(100) Substrates Using The Close-Spaced Sublimation Technique, Hoong Yan See Tao

Open Access Theses & Dissertations

CdTe is an ideal II-VI semiconductor compound with a direct bandgap energy of 1.53 eV used in solar cells and infrared detector applications [8]. The National Renewable Energy Laboratory (NREL) reported that cadmium telluride (CdTe) thin films solar cells have achieved efficiency of 16.5% and with potential for improvement up to the theoretical value of 29% [14]. The close-spaced sublimation (CSS) method used for solar cell CdTe growth is being tested for selective CdTe nanoheteroepitaxial growth because the CSS method is cost efficient compared to the molecular beam epitaxy (MBE) and metalorganic vapor phase epitaxy (MOVPE) methods. High quality films …

Development Of Load Balancing Algorithm Based On Analysis Of Multi-Core Architecture On Beowulf Cluster, Damian Valles

Open Access Theses & Dissertations

In this work, analysis, and modeling were employed to improve the Linux Scheduler for HPC use. The performance throughput of a single compute-node of the 23 node Beowulf cluster, Virgo 2.0, was analyzed to find bottlenecks and limitations that affected performance in the processing hardware where each compute-node consisted of two quad-core processors with eight gigabytes of memory. The analysis was performed using the High Performance Linpack (HPL) benchmark.

In addition, the processing hardware of the compute-node was modeled using an Instruction per Cycle (IPC) metric that was estimated using linear regression. Modeling data was obtained by using the Tuning …

Utepcam: A Scalable Wireless Vision Sensor Architecture For Computational, Power And Bandwidth Constrained Scenarios, Ricardo Zepeda

Open Access Theses & Dissertations

UTEPcam is a low cost and power vision sensor node system. UTEPcam is composed of an Atmel atmega32 8-bit microcontroller, a CY7C09099V static RAM chip, an OV6620 CMOS image sensor, a XBEE transceiver and a SD Flash memory card, and four logic gates. UTEPcam's simple yet efficiently architecture enables it to capture video at one frame per second. At its absolute highest, it is estimated that UTEPcam consumes only 1.321 Amps. When in standby, UTEPcam consumes 21 microamps. Furthermore, UTEPcam's program takes up only 1Kbyte of memory space.

UTEPcam's CPU, a simple 8-bit MCU, is unlike most vision sensor node …

Novel Photovoltaic Device For Targeted Drug Delivery, Sunny S. Ambure

Open Access Theses & Dissertations

Despite decades of research, progress in targeted drug delivery is relatively slow, hampered, in part, by the lack of appropriate mechanisms to deliver anticancer drugs selectively to tumor tissues. Systemic or oral administration can cause severe toxicity, which limits the therapeutic potential of anticancer drugs [1]. Therefore, the most important goal of drug delivery is to minimize the exposure of normal tissues to these drugs while maintaining their therapeutic concentration in tumors.

A photovoltaic cell (PV) is a system that converts lights into electricity as well as induces charge transfer by photovoltaic effect. Motivated by such unique property, we have …

Collaborative And Distributed Algorithms For Localization In Wireless Sensor Networks Based On The Solution Of Spatially Constrained Local And Sub-Local Problems, Juan De Dios Cota

Open Access Theses & Dissertations

In this research we present algorithms for the distributed and collaborative localization of nodes for applications in wireless sensor networks. The algorithms are distributed in the sense that each node can estimate its own position using only range information and position estimates from neighboring nodes. The algorithms aim at achieving good accuracy with low computational complexity and low energy consumption. We consider the full localization process consisting of an initialization stage followed by a refinement stage.

For initialization, we propose a \emph{bilateration} algorithm where each node uses a set of anchors and their respective ranges to solve a set of …

Tin Dioxide Memristors On Glass And Plastic Substrates, Oscar Del Real

Open Access Theses & Dissertations

NanoMIL has studied and developed SnO2-based memristors, while the W.M Keck Center has been a research leader in printed silver inks. The focus of this thesis is to take the previous generation of memristors on glass and develop a process for creating memristors on flexible Kapton film for the first time. Moreover, collaborative work between the two UTEP laboratories produced memristors with printed silver top electrode contacts, also for the first time. These approaches may enable inexpensive flexible memory.

Maturation of the process was achieved by understanding important process parameters and subtle differences between glass and Kapton substrates. Moreover, electrical …

Size Dependent Melting And Diffusion Of Silicon For Microsystem Applications, Noel Felipe Marquez

Open Access Theses & Dissertations

The size dependent reduced melting point and hydrogen enhanced surface diffusion effect on silicon nanostructures was explored experimentally. SOI and silicon wafers were patterned using nanimprint lithography and dry etching to explore the reduced melting point effect; and patterned with photolithography and dry etching to explore the hydrogen enhanced surface diffusion. The nanotextured samples were annealed in a wide variety of furnaces with nitrogen, forming gas, and argon atmospheres. Nitrogen was found to block the reshaping effect while argon was found to cause extensive pitting damage in the setup used. Micropatterned samples were annealed in a low pressure hydrogen enabled …

Impulse Oscillometric Features And Parsimonious Respiratory Models Track Small Airway Function In Hispanic And Anglo Children, Erika Guadalupe Meraz Tena

Open Access Theses & Dissertations

Asthma is an inflammatory condition of the peripheral (small) airways resulting in airway hyper-reactivity and, among other symptoms, airflow obstruction. It is the most prevalent chronic respiratory disease in children. Reliable and patient-friendly instruments and methods are required to help pulmonologists accurately detect asthma and Small Airway Impairment (SAI) with acceptable clinical accuracy, specificity and sensitivity. Impulse Oscillometry System (IOS) based on the Forced Oscillation Technique (FOT) has been successfully used to measure lung function in children with a high degree of sensitivity and specificity to SAI and Asthma. IOS is a patient-friendly lung function to measure the mechanical impedance …

Conformal Electronics Packaging Through Additive Manufacturing And Micro-Dispensing, Richard I. Olivas

Open Access Theses & Dissertations

Realizing electronic systems that are conformal with curved or complex surfaces is difficult if not impossible with conventional fabrication techniques, which require rigid, two dimensional, printed circuit boards (PCB). Flexible copper based fabrication is widely available commercially providing conformance, but not simultaneously stiffness. As a result, these systems are susceptible to reliability problems if repeatedly bent or stretched. The integration of Additive Manufacturing (AM) combined with Direct Print (DP) micro-dispensing can produce shapes of arbitrary and complex form that also allows for 1) miniature cavities for insetting electronic components and 2) conductive traces for electrical interconnect between components. The fabrication …

Algorithms For Training Large-Scale Linear Programming Support Vector Regression And Classification, Pablo Rivas Perea

Open Access Theses & Dissertations

The main contribution of this dissertation is the development of a method to train a Support Vector Regression (SVR) model for the large-scale case where the number of training samples supersedes the computational resources. The proposed scheme consists of posing the SVR problem entirely as a Linear Programming (LP) problem and on the development of a sequential optimization method based on variables decomposition, constraints decomposition, and the use of primal-dual interior point methods. Experimental results demonstrate that the proposed approach has comparable performance with other SV-based classifiers. Particularly, experiments demonstrate that as the problem size increases, the sparser the solution …