Engineering Commons^™

Electricity Markets, Smart Grids And Smart Buildings, Jonathan Falcey

Electronic Theses and Dissertations

A smart grid is an electricity network that accommodates two-way power flows, and utilizes two-way communications and increased measurement, in order to provide more information to customers and aid in the development of a more efficient electricity market. The current electrical network is outdated and has many shortcomings relating to power flows, inefficient electricity markets, generation/supply balance, a lack of information for the consumer and insufficient consumer interaction with electricity markets. Many of these challenges can be addressed with a smart grid, but there remain significant barriers to the implementation of a smart grid.

This paper proposes a novel method …

Reducing Communication Delay Variability For A Group Of Robots, Goncalo Martins

Electronic Theses and Dissertations

A novel architecture is presented for reducing communication delay variability for a group of robots. This architecture relies on using three components: a microprocessor architecture that allows deterministic real-time tasks; an event-based communication protocol in which nodes transmit in a TDMA fashion, without the need of global clock synchronization techniques; and a novel communication scheme that enables deterministic communications by allowing senders to transmit without regard for the state of the medium or coordination with other senders, and receivers can tease apart messages sent simultaneously with a high probability of success. This approach compared to others, allows simultaneous communications without …

Exploration Of The Impact Of Affective Variables On Human Performance In A Live Simulation, Ken Westerlund

Electronic Theses and Dissertations

Live simulations play an important role in allowing users to practice and develop skills they learn in training. Although live simulations are playing an increasingly important role in training, ways to improve them are not well understood or documented. In order to improve the efficacy of live simulation and maximize results from funds spent on training; this research examines the relationship between the affective variables of the participants and their performance in the live simulation. Prior to participating in the instructor development live simulation used in this study two training preference scales were administered to a group of trainees. These …

External Cavity Mode-Locked Semiconductor Lasers For The Generation Of Ultra-Low Noise Multi-Gigahertz Frequency Combs And Applications In Multi-Heterodyne Detection Of Arbitrary Optical Waveforms, Josue Davila-Rodriguez

Electronic Theses and Dissertations

The construction and characterization of ultra-low noise semiconductor-based mode-locked lasers as frequency comb sources with multi-gigahertz combline-to-combline spacing is studied in this dissertation. Several different systems were built and characterized. The first of these systems includes a novel mode-locking mechanism based on phase modulation and periodic spectral filtering. This mode-locked laser design uses the same intra-cavity elements for both mode-locking and frequency stabilization to an intra-cavity, 1,000 Finesse, Fabry-Pérot Etalon (FPE). On a separate effort, a mode-locked laser based on a Slab-Coupled Optical Waveguide Amplifier (SCOWA) was built. This system generates a pulse-train with residual timing jitter of

Galvanic Corrosion Of High-Temperature Low-Sag (Htls) High Voltage Conductors: New Materials—New Challenges, Eva Håkansson

Electronic Theses and Dissertations

High-Temperature Low-Sag (HTLS) high voltage overhead conductors offer higher operating temperatures, reduced resistance and less sag than conventional designs. With up to twice the current capacity for the same diameter conductor, they may help ease the power shortage in the constantly increasing electricity demand, but there might be some concerns about their corrosion resistance.

These new conductors use materials relatively new to the power industry, such as advanced carbon fiber polymer matrix composites and unique metal matrix composites/nano-composites predominantly used in aerospace industries. This study has made an initial assessment of potential galvanic corrosion problems in three very different HTLS …

Robot Team Formation Control Using Communication "Throughput Approach", Fatmazahra Ahmed Benhalim

Electronic Theses and Dissertations

In this thesis, we consider a team of robots forming a mobile robot network cooperating to accomplish a mission in an unknown but structured environment. The team has no a-priori knowledge of the environment. Robots have limited memory storage capabilities, not enough to map the environment. Each robot also has limited sensor capability and computational power. Due to the need to avoid obstacles and other environment effects, some robots get delayed from the rest. Using tracking controller, the robot team should follow the leader in a flexible formation shape without losing network connectivity, and that was achieved by monitoring the …

Finite Element Analysis Of Thermomechanical Processes In Disk Clutch Systems, Zhuo Chen

Electronic Theses and Dissertations

The engagement of clutch system is a typical dynamic coupled temperature-displacement process which contains two or more sliding surfaces involved in frictional contact. This process influences evidently the thermal fatigue, noise and vibration of the clutch system. This effect can be more remarkable if the temperature distribution over the clutch disk is not uniform.

This thesis is organized into five chapters:

The first chapter is an introduction which reviews the background and previous work of thermoelastic instability and finite element analysis of clutch system and disk brake.

A parametric analysis of TEI (thermoelastic instability) is elaborated in the second chapter. …

Control Of Harmonics In 6-Pulse Rectifiers, Sudeep K. Pyakuryal

Electronic Theses and Dissertations

Harmonics are always present in electrical power systems. Harmonic distortion is harmless as long as its level is within the limit. However, with the recent rapid advancement of power electronics, i.e. non linear loads, the use of the variable speed drives are increasing day by day. Harmonics produced by non-linear loads are a potential risk if they are not evaluated, predicted, and controlled.

The power electronic switching devices like thyristor used in the rectifier circuits inject harmonic distortion to the utility grid in different applications. The harmonic distortion causes different problems in the power system. To minimize the unwanted effects …

Optimization Of Spray Droplet Size For Drug Delivery To The Deep Lung, Renee Worden

Electronic Theses and Dissertations

The lower respiratory regions of the lung boast over 900 million alveoli with a combined 85 m2 of surface area of near direct access to the bloodstream. Within the last century the immense potential of the deep lung as a site for the delivery of drugs has begun to be exploited and today pulmonary delivery of aerosolized therapeutic is commonplace. However, the high inter- and intra-patient variability in dosing is almost completely ignored. Currently, no steps are being taken to mitigate the sources of variability beyond injection into the upper airways. This study seeks to prove that a careful selection …

Combustion Synthesis And Characterization Of Porous Niti Intermetallic For Structural Application, Jessica Vanterpool

Electronic Theses and Dissertations

This thesis describes experimental investigation of thermal and combustion phenomena as well as structure for self- propagating combustion synthesis of porous Ni - Ti intermetallic aimed for structural biomedical application. The control parameters for the porosity distribution have been investigated experimentally through varying the preheat temperature, initial porosity, initial elemental particle size, and applied pressure during the fabrication process. Ni and Ti elemental powders are mixed using a 1:1 ratio. The mixture is compressed using several different compression forces to produce cylindrical samples of 1.1 cm diameter and 2-3cm length, with initial porosity ranging from 30% to 40%. The samples …

Bridging The Gap Between Fun And Fitness: Instructional Techniques And Real-World Applications For Full-Body Dance Games, Emiko Charbonneau

Electronic Theses and Dissertations

Full-body controlled games offer the opportunity for not only entertainment, but education and exercise as well. Refined gameplay mechanics and content can boost intrinsic motivation and keep people playing over a long period of time, which is desirable for individuals who struggle with maintaining a regular exercise program. Within this gameplay genre, dance rhythm games have proven to be popular with game console owners. Yet, while other types of games utilize story mechanics that keep players engaged for dozens of hours, motion-controlled dance games are just beginning to incorporate these elements. In addition, this control scheme is still young, only …

Learning Hierarchical Representations For Video Analysis Using Deep Learning, Yang Yang

Electronic Theses and Dissertations

With the exponential growth of the digital data, video content analysis (e.g., action, event recognition) has been drawing increasing attention from computer vision researchers. Effective modeling of the objects, scenes, and motions is critical for visual understanding. Recently there has been a growing interest in the bio-inspired deep learning models, which has shown impressive results in speech and object recognition. The deep learning models are formed by the composition of multiple non-linear transformations of the data, with the goal of yielding more abstract and ultimately more useful representations. The advantages of the deep models are three fold: 1) They learn …

Metrology Of Volume Chirped Bragg Gratings Recorded In Photo-Thermo-Refractive Glass For Ultrashort Pulse Stretching And Compressing, Christopher Lantigua

Electronic Theses and Dissertations

Chirped Bragg gratings (CBGs) recorded in photo-thermo-refractive (PTR) glass provide a very efficient and robust way to stretch and compress ultra-short laser pulses. These gratings offer the ability to stretch pulses from hundreds of femtoseconds, to the order of 1 ns and then recompress them. However, in order to achieve pulse stretching of this magnitude, 100 mm thick CBGs are needed. Using these CBGs to both stretch, and re-compress the pulse thus requires propagation through 200 mm of optical glass. This therefore demands perfect control of the glass homogeneity, as well as the holographic recording process of the CBG. In …

Impact Mechanics Of A Lap Joint: A Theoretical-Based Parametric Study, Seyed Amir Mansoor Rahmani

Electronic Theses and Dissertations

The failure of a single connection can cause overload on other structural members, which may consequently fail. Thus, the behavior of damaged or worn joints is of particular concern. In order to represent a loose lap joint, a beam impacting four springs with gaps is modeled. A basis analysis reveals impulse frequency responses with unique dynamic phenomena. Using steady state response, six influential parameters are studied: damping ratio, contact stiffness, position of intermediate springs, gaps, excitation amplitude and beam height. For all parameters, the system response was highly controlled by modes with two contacting springs. Regarding damping, increasing damping ratio …

Physical, Mechanical And Chemical Aging Of Polyurea Nanocomposites, Ghanshyam Pal

Electronic Theses and Dissertations

Two component polyurea systems, on one hand, are gaining popularity as corrosion and abrasion resistant coatings and linings while on the other hand there are a few polyurea compositions being used as barrier against blast and ballistic threats to protect nation's critical infrastructure. Physical properties of polymer composites can be tailored with appropriate choice of type, size and amount of reinforcement. In general, nano-sized reinforcements provide better reinforcing over conventional reinforcements due to higher surface to volume ratio. In this dissertation, the first aim is to study effect of nanoreinforcement addition on the overall character (mechanical, chemical and microstructural) of …

Low Strain Rate Studies Of Alumina Epoxy Composites Using Piezospectroscopy, Ashley Jones

Electronic Theses and Dissertations

Particulate composites are widely used in many aerospace and military applications as energetic materials, armor materials or coatings and their behavior under dynamic loads have gained increasing significance. The addition of modifiers such as alumina nanoparticles generally facilitates the improvement of the mechanical strength to density ratio due to high specific area and particle rigidity. This allows for sufficient particlematrix bonding and therefore improved stiffness and load transfer in the composite. Photo-luminescent α-alumina nanoparticles when embedded in an epoxy matrix allow for the added benefit of in situ measurements at low strain rates to provide stress-sensitive information using the particle …

Electrohydrodynamic Manipulation Of Liquid Droplet Emulsions In A Microfluidic Channel, Jonathan Wehking

Electronic Theses and Dissertations

This work specifically aims to provide a fundamental framework, with some experimental validation, for understanding droplet emulsion dynamics in a microfluidic channel with an applied electric field. Electrification of fluids can result in several different modes of electrohydrodynamics (EHD). Several studies to date have provided theoretical, experimental, and numerical results for stationary droplet deformations and some flowing droplet configurations, but none have reported a method by which droplets of different diameters can be separated, binned and routed through the use of electric fields. It is therefore the goal of this work to fill that void and report a comprehensive understanding …

Monitoring For Underdetermined Underground Structures During Excavation Using Limited Sensor Data, Nader Mehdawi

Electronic Theses and Dissertations

A realistic field monitoring application to evaluate close proximity tunneling effects of a new tunnel on an existing tunnel is presented. A blind source separation (BSS)-based monitoring framework was developed using sensor data collected from the existing tunnel while the new tunnel was excavated. The developed monitoring framework is particularly useful to analyze underdetermined systems due to insufficient sensor data for explicit input force-output deformation relations. The analysis results show that the eigen-parameters obtained from the correlation matrix of raw sensor data can be used as excellent indicators to assess the tunnel structural behaviors during the excavation with powerful visualization …

Computational Methods For Comparative Non-Coding Rna Analysis: From Structural Motif Identification To Genome-Wide Functional Classification, Cuncong Zhong

Electronic Theses and Dissertations

Recent advances in biological research point out that many ribonucleic acids (RNAs) are transcribed from the genome to perform a variety of cellular functions, rather than merely acting as information carriers for protein synthesis. These RNAs are usually referred to as the non-coding RNAs (ncRNAs). The versatile regulation mechanisms and functionalities of the ncRNAs contribute to the amazing complexity of the biological system. The ncRNAs perform their biological functions by folding into specific structures. In this case, the comparative study of the ncRNA structures is key to the inference of their molecular and cellular functions. We are especially interested in …

Development Of An Oceanic Rain Accumulation Product In Support Of Sea Surface Salinity Measurements From Aquarius/Sac-D, Shadi Aslebagh

Electronic Theses and Dissertations

Aquarius/SAC-D is a joint mission by National Aeronautics and Space Administration (NASA) and the Comision Nacional de Actividades Espaciales (CONAE), Argentine Space Agency. The satellite was launched in June 2011 and the prime remote sensing instrument is also named Aquarius (AQ). The main objective of this science program is to provide Sea Surface Salinity (SSS) maps of the global oceans every 7 days for understanding the Earth’s hydrologic cycle and for assessing long-term global climate change. The Aquarius instrument was built jointly by NASA’s Goddard Space Flight Center and the Jet Propulsion Laboratory. It is an active/passive L-band remote sensor …

Cooperative Control And Advanced Management Of Distributed Generators In A Smart Grid, Ali Maknouninejad

Electronic Theses and Dissertations

Smart grid is more than just the smart meters. The future smart grids are expected to include a high penetration of distributed generations (DGs), most of which will consist of renewable energy sources, such as solar or wind energy. It is believed that the high penetration of DGs will result in the reduction of power losses, voltage profile improvement, meeting future load demand, and optimizing the use of non-conventional energy sources. However, more serious problems will arise if a decent control mechanism is not exploited. An improperly managed high PV penetration may cause voltage profile disturbance, conflict with conventional network …

On-Chip Electro-Static Discharge (Esd) Protection For Radio-Frequency Integrated Circuits, Qiang Cui

Electronic Theses and Dissertations

Electrostatic Discharge (ESD) phenomenon is a common phenomenon in daily life and it could damage the integrated circuit throughout the whole cycle of product from the manufacturing. Several ESD stress models and test methods have been used to reproduce ESD events and characterize ESD protection device's performance. The basic ESD stress models are: Human Body Model (HBM), Machine Model (MM), and Charged Device Model (CDM). On-chip ESD protection devices are widely used to discharge ESD current and limit the overstress voltage under different ESD events. Some effective ESD protection devices were reported for low speed circuit applications such as analog …

Modeling Learner Mood In Realtime Through Biosensors For Intelligent Tutoring Improvements, Keith Brawner

Electronic Theses and Dissertations

Computer-based instructors, just like their human counterparts, should monitor the emotional and cognitive states of their students in order to adapt instructional technique. Doing so requires a model of student state to be available at run time, but this has historically been difficult. Because people are different, generalized models have not been able to be validated. As a person’s cognitive and affective state vary over time of day and seasonally, individualized models have had differing difficulties. The simultaneous creation and execution of an individualized model, in real time, represents the last option for modeling such cognitive and affective states. This …

Planning And Control Of Swarm Motion As Continua, Hossein Rastgoftar

Electronic Theses and Dissertations

In this thesis, new algorithms for formation control of multi agent systems (MAS) based on continuum mechanics principles will be investigated. For this purpose agents of the MAS are treated as particles in a continuum, evolving in an n-D space, whose desired configuration is required to satisfy an admissible deformation function. Considered is a specific class of mappings that is called homogenous where the Jacobian of the mapping is only a function of time and is not spatially varying. The primary objectives of this thesis are to develop the necessary theory and its validation via simulation on a mobile-agent based …

Life Long Learning In Sparse Learning Environments, John Reeder

Electronic Theses and Dissertations

Life long learning is a machine learning technique that deals with learning sequential tasks over time. It seeks to transfer knowledge from previous learning tasks to new learning tasks in order to increase generalization performance and learning speed. Real-time learning environments in which many agents are participating may provide learning opportunities but they are spread out in time and space outside of the geographical scope of a single learning agent. This research seeks to provide an algorithm and framework for life long learning among a network of agents in a sparse real-time learning environment. This work will utilize the robust …

Development Of Polymer Derived Sialcn Ceramic And Its Applications For High-Temperature Sensors, Gang Shao

Electronic Theses and Dissertations

Polymer-derived ceramic (PDC) is the name for a class of materials synthesized by thermal decomposition of polymeric precursors which excellent thermomechanical properties, such as high thermal stability, high oxidation/corrosion resistance and high temperature multifunctionalities. Direct polymer-to-ceramic processing routes of PDCs allow easier fabrication into various components/devices with complex shapes/structures. Due to these unique properties, PDCs are considered as promising candidates for making high-temperature sensors for harsh environment applications, including high temperatures, high stress, corrosive species and/or radiation. The SiAlCN ceramics were synthesized using the liquid precursor of polysilazane (HTT1800) and aluminum-sec-tri-butoxide (ASB) as starting materials and dicumyl peroxide (DP) as …

Generation And Printing Of Strictly Monodisperse Droplets, Hongxu Duan

Electronic Theses and Dissertations

Highly monodisperse droplets are attracting great attention both in many research areas, such as aerosol science, combustion, and Nano-manufacturing. This thesis invents a novel aerosol generator: “Periodic Electro Hydro-dynamic Chopper” termed as “PEHD chopper”, and develops a new method to directly print micro-patterns with monodisperse droplets. The principle of the PEHD chopper is to use the fringe electric field of a capacitor to introduce controlled perturbation on a liquid jet. We first derived the governing equations for a circular inviscid liquid jet under transverse electric fields. The electric fields were obtained through numerical simulation. Then we used a high speed …

Integrating Multiobjective Optimization With The Six Sigma Methodology For Online Process Control, Emad Abualsauod

Electronic Theses and Dissertations

Over the past two decades, the Define-Measure-Analyze-Improve-Control (DMAIC) framework of the Six Sigma methodology and a host of statistical tools have been brought to bear on process improvement efforts in today’s businesses. However, a major challenge of implementing the Six Sigma methodology is maintaining the process improvements and providing real-time performance feedback and control after solutions are implemented, especially in the presence of multiple process performance objectives. The consideration of a multiplicity of objectives in business and process improvement is commonplace and, quite frankly, necessary. However, balancing the collection of objectives is challenging as the objectives are inextricably linked, and, …

A Posteriori And Interactive Approaches For Decision-Making With Multiple Stochastic Objectives, Ahmed Bakhsh

Electronic Theses and Dissertations

Computer simulation is a popular method that is often used as a decision support tool in industry to estimate the performance of systems too complex for analytical solutions. It is a tool that assists decision-makers to improve organizational performance and achieve performance objectives in which simulated conditions can be randomly varied so that critical situations can be investigated without real-world risk. Due to the stochastic nature of many of the input process variables in simulation models, the output from the simulation model experiments are random. Thus, experimental runs of computer simulations yield only estimates of the values of performance objectives, …

Speech Detection Using Gammatone Features And One-Class Support Vector Machine, Douglas Cooper

Electronic Theses and Dissertations

A network gateway is a mechanism which provides protocol translation and/or validation of network traffic using the metadata contained in network packets. For media applications such as Voice-over-IP, the portion of the packets containing speech data cannot be verified and can provide a means of maliciously transporting code or sensitive data undetected. One solution to this problem is through Voice Activity Detection (VAD). Many VAD’s rely on time-domain features and simple thresholds for efficient speech detection however this doesn’t say much about the signal being passed. More sophisticated methods employ machine learning algorithms, but train on specific noises intended for …