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Full-Text Articles in Physical Sciences and Mathematics

Development Of Sensor, Sensory System And Signal Processing Algorithm For Intelligent Sensing Applications, Xingzhe Zhang Nov 2021

Development Of Sensor, Sensory System And Signal Processing Algorithm For Intelligent Sensing Applications, Xingzhe Zhang

Dissertations

Sensors have been receiving significant attention in the last decade and the demand for sensory systems has increased in recent years due to the rapid growth in the field of artificial intelligence (AI). Sensors can improve people’s awareness by providing them with real-time information on the environment and their immediate health conditions. This dissertation presents the fulfilment of three main projects and focuses on the development of a sensor, a sensory system, and a sensor signal recognition system for AI applications by employing printed electronics, analog circuit design, and digital signal processing techniques.

In the first project, a multi-channel stethograph …


Advancing The Use Of Quality Control Tools For High-Density Data In Modern Manufacturing, Romina Dastoorian May 2021

Advancing The Use Of Quality Control Tools For High-Density Data In Modern Manufacturing, Romina Dastoorian

Dissertations

In modern manufacturing, advanced metrology systems are continually being incorporated into quality control (QC) systems to provide high-density (HD) datasets. These datasets can contain millions of measurements that can be used to represent a part’s whole geometry. While integrating HD datasets into QC systems has brought several opportunities to enhance the performance of QC systems, it has resulted in new challenges in this area as well. While significant amounts of research have been performed in this area, the QC research community still strives to tackle these challenges. This study identifies key challenges regarding incorporating HD datasets into QC systems. Specifically, …


Application Of Artificial Intelligence And Geographic Information System For Developing Automated Walkability Score, Md Mehedi Hasan Aug 2020

Application Of Artificial Intelligence And Geographic Information System For Developing Automated Walkability Score, Md Mehedi Hasan

Dissertations

Walking is considered as one of the major modes of active transportation, which contributes to the livability of cities. It is highly important to ensure walk friendly sidewalks to promote human physical activities along roads. Over the last two decades, different walk scores were estimated in respect to walkability measures by applying different methods and approaches. However, in the era of big data and machine learning revolution, there is still a gap to measure the composite walkability score in an automated way by applying and quantifying the activityfriendliness of walkable streets. In this study, a street-level automated walkability score was …


Accumulation Of Polar Vorticity On Giant Planets: Towards A Three-Dimensional Theory, Shawn R. Brueshaber Aug 2020

Accumulation Of Polar Vorticity On Giant Planets: Towards A Three-Dimensional Theory, Shawn R. Brueshaber

Dissertations

My research investigates the polar atmospheric dynamics of the giant planets: Jupiter and Saturn (gas giants), and Uranus and Neptune (ice giants). I conduct my research modifying and applying the Explicit Planetary Isentropic Coordinate global circulation code to model the polar regions of the four giant planets.

The motivation behind my research is to uncover the reason why giant planet polar atmospheric dynamics differ. Jupiter features multiple circumpolar cyclones arranged in geometrical configurations, whereas Saturn features a single pole-centered cyclone. Uranus and Neptune also appear to have single pole-centered cyclones, albeit, larger than those on Saturn. …


Embedded Gold Nanoparticles For Metal Enhanced Photoluminescence, Hasna Alali Aug 2020

Embedded Gold Nanoparticles For Metal Enhanced Photoluminescence, Hasna Alali

Dissertations

Noble metal nanoparticles (MNPs) have attracted great attention in electronics, solar cells and catalysis. Their unique optical properties and biocompatibility makes them useful in biological applications like imaging, drug delivery, therapy and diagnostic. At the surface of MNPs the collective oscillation of free electrons resonates with a particular wavelength of incident light, generating the Localized Surface Plasmons Resonance (LSPR). LSPR results in absorption and scattering of incident light. Scattering results in reflecting photons and absorption leads to enhanced photoluminescence and quenching of fluorophores, if the fluorophore is in the vicinity of MNPs.

Most of the studies in this regard have …


Retinex-Based Visibility Enhancement System For Inclement Weather With Tracking And Distance Estimation Capabilities, Marwan S. Alluhaidan Dec 2018

Retinex-Based Visibility Enhancement System For Inclement Weather With Tracking And Distance Estimation Capabilities, Marwan S. Alluhaidan

Dissertations

Road conditions affected by weather are well known to have an impact on the number of vehicle accidents and fatalities, due to low- to no-visibility conditions. According to the U.S. Department of Transportation, there are more than 1,259,000 crashes each year. On average, 6,000 people are killed and more than 445,000 people are injured annually due to severe weather conditions. These accidents could be significantly reduced if real-time visibility enhancement systems were made available. However, eliminating the impact of weather conditions on visibility is still lacking and beyond our control. The time has come to develop technology that is capable …


A 3d Simulation Of Leukocyte Adhesion In Blood Flow, Tai-Hsien Wu Jun 2018

A 3d Simulation Of Leukocyte Adhesion In Blood Flow, Tai-Hsien Wu

Dissertations

It has been widely acknowledged that further understanding about the dynamics between blood cells and blood flow can help us gain more knowledge about the causes of diseases and discover more effective treatments. Examples of such dynamics include red blood cell (RBC, or erythrocyte) aggregation, white blood cell (WBC, or leukocyte) margination, and WBC extravasation. WBC extravasation is an important multiple-step process in the inflammatory response and therefore has drawn considerable attention over the past two decades. In this multiple-step process, a WBC undergoes at least four steps, including capture, rolling, firm adhesion, and transmigration, and each step is influenced …


Novel Software Defined Radio Architecture With Graphics Processor Acceleration, Lalith Narasimhan Dec 2015

Novel Software Defined Radio Architecture With Graphics Processor Acceleration, Lalith Narasimhan

Dissertations

Wireless has become one of the most pervasive core technologies in the modern world. Demand for faster data rates, improved spectrum efficiency, higher system access capacity, seamless protocol integration, improved security and robustness under varying channel environments has led to the resurgence of programmable software defined radio (SDR) as an alternative to traditional ASIC based radios. Future SDR implementations will need support for multiple standards on platforms with multi-Gb/s connectivity, parallel processing and spectrum sensing capabilities. This dissertation implemented key technologies of importance in addressing these issues namely development of cost effective multi-mode reconfigurable SDR and providing a framework to …


Opportunistic Service Differentiation And Cloud Resource Management In Support Of Enhanced Vehicular Applications, Mohammad Ali Salahuddin Jun 2014

Opportunistic Service Differentiation And Cloud Resource Management In Support Of Enhanced Vehicular Applications, Mohammad Ali Salahuddin

Dissertations

An integral part of Intelligent Transportation Systems (ITS) are Vehicular Ad hoc Networks (VANETs), which consist of vehicles with on-board units (OBUs) and fixed road-side units (RSUs). Wireless Access in Vehicular Environment (WAVE) offers QoS via service differentiation by using application defined priorities. However, WAVE has unbounded delay and is oblivious to network load and severity of vehicles with respect to their environment. Our context severity metric innovatively enhances WAVE to be sensitive to vehicle and environment interactions. Our novel Opportunistic Service Differentiation (OSD) technique, dynamically readjusts the WAVE packet priorities to improve utilization of lower latency queues, prioritizing packets …


Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors, Liyana A. Wajira Ariyadasa Apr 2014

Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors, Liyana A. Wajira Ariyadasa

Dissertations

In recent years, nanoscale metallic particles have gained considerable interest due to their potential applications in advanced technology. Despite such interest, synthetic procedures that produce gram-scale, well-defined metallic nanoparticles with controlled size and shape, especially with diameters less than 5 nm remains a challenge. Our work has focused on developing synthetic procedures that produce well-defined platinum and palladium metal nanoparticles in the 1-5 nm size range. Thioether ligands were used as stabilizers and resulted in metal nanoparticles with controlled size. The nanoparticles were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy …


A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown Apr 2014

A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown

Dissertations

This study systematically reviews the methodological characteristics of energy efficiency evaluations and uses metaevaluation to assess its quality. Metaevaluation is used to systematically assess the quality of evaluation products, confirm that evaluations deliver sound findings and conclusions, are useful to the client, are credible, are ethically conducted, and are done as cost-effective as possible. The results of this study show that the ability to accurately assess evaluation for methodological quality using evaluations reports as a primary data source depends on the presence of detailed descriptions of evaluation methods. Furthermore, the study suggests that methodological variations of energy efficiency evaluations coalesce …


Organic Solar Cells Based On High Dielectric Constant Materials: An Approach To Increase Efficiency, Khalil Jumah Tawfiq Hamam Jun 2013

Organic Solar Cells Based On High Dielectric Constant Materials: An Approach To Increase Efficiency, Khalil Jumah Tawfiq Hamam

Dissertations

The efficiency of organic solar cells still lags behind inorganic solar cells due to their low dielectric constant which results in a weakly screened columbic attraction between the photogenerated electron-hole system, therefore the probability of charge separating is low. Having an organic material with a high dielectric constant could be the solution to get separated charges or at least weakly bounded electron-hole pairs. Therefore, high dielectric constant materials have been investigated and studied by measuring modified metal-phthalocyanine (MePc) and polyaniline in pellets and thin films. The dielectric constant was investigated as a function of temperature and frequency in the range …


Compositional And Structural Analysis Of Nitrogen Incorporated And Ion Implanted Diamond Thin Films, Elias James Garratt Apr 2013

Compositional And Structural Analysis Of Nitrogen Incorporated And Ion Implanted Diamond Thin Films, Elias James Garratt

Dissertations

Significant progress in area of nano-structured thin film systems has taken place in recent decades. In particular, diamond thin film systems are being widely studied for their wear resistant, optical and electronic properties. Of the various methods researchers use to modify the structure of such films, three techniques in particular are of interest due to their versatility: modification of the growth atmosphere, growth on metalized substrates, providing an interfacial layer, and modification through post-growth ion implantation. The aim of this study is to investigate the effects each has to the structure and composition of elements. Different techniques are applied in …


Adaptive Security-Aware Scheduling For Packet Switched Networks Using Real-Time Multi-Agent Systems, Ma'en Saleh Saleh Jun 2012

Adaptive Security-Aware Scheduling For Packet Switched Networks Using Real-Time Multi-Agent Systems, Ma'en Saleh Saleh

Dissertations

Conventional real-time scheduling algorithms are in care of timing constraints; they don’t pay any attention to enhance or optimize the real-time packet’s security performance. In this work, we propose an adaptive security-aware scheduling with congestion control mechanism for packet switching networks using real-time agentbased systems. The proposed system combines the functionality of real-time scheduling with the security service enhancement, where the real-time scheduling unit uses the differentiated-earliest-deadline-first (Diff-EDF) scheduler, while the security service enhancement scheme adopts a congestion control mechanism based on a resource estimation methodology.

The security service enhancement unit was designed based on two models: singlelayer and weighted …


Leach-Sm: A Protocol For Extending Wireless Sensor Network Lifetime By Management Of Spare Nodes, Bilal Abu Bakr Jan 2011

Leach-Sm: A Protocol For Extending Wireless Sensor Network Lifetime By Management Of Spare Nodes, Bilal Abu Bakr

Dissertations

Operational lifetime of a wireless sensor network (WSN) depends on its energy resources. Significant improvement of WSN lifetime can be achieved by adding spare sensor nodes to WSN. Spares are ready to be switched on when any primary (a node that is not a spare) exhausts its energy. A spare replacing a primary becomes a primary itself.

The LEACH-SM protocol (Low-Energy Adaptive Clustering Hierarchy with Spare Management) proposed by us is a modification of the prominent LEACH protocol. LEACH extends WSN lifetime via rotation of cluster heads but allows for inefficiencies due to redundant sensing target coverage. There are two …