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Transcriptional And Post-Transcriptional Regulation Of Gene Expression, Jun Ding
Transcriptional And Post-Transcriptional Regulation Of Gene Expression, Jun Ding
Electronic Theses and Dissertations
Regulation of gene expression includes a variety of mechanisms to increase or decrease specific gene products. Gene expression can be regulated at any stage from transcription to post-transcription and it's essential to almost all living organisms, as it increases the versatility and adaptability by allowing the cell to express the needed proteins. In this dissertation, we comprehensively studied the gene regulation from both transcriptional and post-transcriptional points of view. Transcriptional regulation is by which cells regulate the transcription from DNA to RNA, thereby directing gene activity. Transcriptional factors (TFs) play a very important role in transcriptional regulation and they are …
Evaluation Of Crash Modification Factors And Functions Including Time Trends At Intersections, Jung-Han Wang
Evaluation Of Crash Modification Factors And Functions Including Time Trends At Intersections, Jung-Han Wang
Electronic Theses and Dissertations
Traffic demand has increased as population increased. The US population reached 313,914,040 in 2012 (US Census Bureau, 2015). Increased travel demand may have potential impact on roadway safety and the operational characteristics of roadways. Total crashes and injury crashes at intersections accounted for 40% and 44% of traffic crashes, respectively, on US roadways in 2007 according to the Intersection Safety Issue Brief (FHWA, 2009). Traffic researchers and engineers have developed a quantitative measure of the safety effectiveness of treatments in the form of crash modification factors (CMF). Based on CMFs from multiple studies, the Highway Safety Manual (HSM) Part D …
Investigation Of Infrared Thermography For Subsurface Damage Detection Of Concrete Structures, Shuhei Hiasa
Investigation Of Infrared Thermography For Subsurface Damage Detection Of Concrete Structures, Shuhei Hiasa
Electronic Theses and Dissertations
Deterioration of road infrastructure arises from aging and various other factors. Consequently, inspection and maintenance have been a serious worldwide problem. In the United States, degradation of concrete bridge decks is a widespread problem among several bridge components. In order to prevent the impending degradation of bridges, periodic inspection and proper maintenance are indispensable. However, the transportation system faces unprecedented challenges because the number of aging bridges is increasing under limited resources, both in terms of budget and personnel. Therefore, innovative technologies and processes that enable bridge owners to inspect and evaluate bridge conditions more effectively and efficiently with less …
Towards Energy-Efficient And Reliable Computing: From Highly-Scaled Cmos Devices To Resistive Memories, Soheil Salehi Mobarakeh
Towards Energy-Efficient And Reliable Computing: From Highly-Scaled Cmos Devices To Resistive Memories, Soheil Salehi Mobarakeh
Electronic Theses and Dissertations
The continuous increase in transistor density based on Moore's Law has led us to highly scaled Complementary Metal-Oxide Semiconductor (CMOS) technologies. These transistor-based process technologies offer improved density as well as a reduction in nominal supply voltage. An analysis regarding different aspects of 45nm and 15nm technologies, such as power consumption and cell area to compare these two technologies is proposed on an IEEE 754 Single Precision Floating-Point Unit implementation. Based on the results, using the 15nm technology offers 4-times less energy and 3-fold smaller footprint. New challenges also arise, such as relative proportion of leakage power in standby mode …
Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad
Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad
Electronic Theses and Dissertations
The objective of this study is to analyze the driving behavior at toll plazas by examining multiple scenarios using a driving simulator to study the effect of different options including different path decisions, various signs, arrow markings, traffic conditions, and extending auxiliary lanes before and after the toll plaza on the driving behavior. Also, this study focuses on investigating the effect of drivers' characteristics on the dangerous driving behavior (e.g. speed variation, sudden lane change, drivers' confusion). Safety and efficiency are the fundamental goals that transportation engineering is always seeking for the design of highways. Transportation agencies have a crucial …
Electrical Parasitic Bandwidth Limitations Of Oxide-Free Lithographic Vertical-Cavity Surface-Emitting Lasers, Xu Yang
Electronic Theses and Dissertations
Nowadays, Vertical-Cavity Surface-Emitting Lasers (VCSELs) are the most popular optical sources in short-reach data communications. In the commercial oxide VCSEL technology, an oxide aperture is created inside resonant cavity in realizing good mode and current confinement, however, high electrical resistance comes along with forming the oxide aperture and the electrical parasitic bandwidth becomes the main limitation in modulation speed. In this report, electrical bandwidths of oxide-free lithographic VCSELs have been studied along with their general lasing properties. Due to the new ways of fabricating the aperture, record low resistances have been achieved in oxide-free lithographic VCSELs with various sizes, while …
Kinematical Modelling And Its Analytical Inverse Kinematic Solution For The Handling Mechanism Of An Agricultural Robot, Sinem Gozde Defterli
Kinematical Modelling And Its Analytical Inverse Kinematic Solution For The Handling Mechanism Of An Agricultural Robot, Sinem Gozde Defterli
Electronic Theses and Dissertations
Early detection of the crop diseases helps to prevent failure in the amount and the quality of the production. In agricultural robotics, the idea of a disease detection robot is a fresh and an innovative hot-button topic. The exclusion of the diseased parts from the strawberry plants for further analyses is one of the main tasks of a recently developed strawberry robot. To this purpose, the handling mechanism in the robot needs to achieve an accurate manipulation task to reach the target. Reaching, cutting and storing the diseased leaf are challenging and delicate processes during the procedure of the handling …
High Average Power Nanosecond Pulsed Tm:Fiber Laser For Pumping An Optical Parametric Oscillator, Ali Abdulfattah
High Average Power Nanosecond Pulsed Tm:Fiber Laser For Pumping An Optical Parametric Oscillator, Ali Abdulfattah
Electronic Theses and Dissertations
Thulium-doped fiber lasers operating with wavelengths in the vicinity of 2 µm are useful for several emerging applications including generating mid-IR light via nonlinear frequency conversion. In this study we describe the design and construction of a thulium fiber laser system comprising a master oscillator and a power amplifier. The first stage is a Q-switched, thulium-doped photonic crystal fiber oscillator utilizing an acousto-optic modulator to produce 65-80 nanosecond pulses. A diffraction grating in the cavity provides wavelength tunability from 1.8 – 2µm. The oscillator produced up to 3 W of average power and 150 µJ pulse energies, corresponding to 2.3 …
Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi
Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi
Electronic Theses and Dissertations
Sinkholes are natural geohazard phenomena that cause damage to property and may lead to loss of life. They can also cause added pollution to the aquifer by draining unfiltered water from streams, wetland, and lakes into the aquifer. Sinkholes occur in a very distinctive karst geology where carbonate, limestone, dolomite, or gypsum, are encountered as the bedrock that can naturally be dissolved by groundwater circulating through them. Sinkholes can occur gradually or suddenly with catastrophic impact depending on the geology and hydrology of the area. Predicting the formation and the collapse of a sinkhole based on the current ground investigation …
Smart Grid Demonstration: Distributed Active And Reactive Power Control, Siddarth Vellakovil Rajamani
Smart Grid Demonstration: Distributed Active And Reactive Power Control, Siddarth Vellakovil Rajamani
Electronic Theses and Dissertations
The present infrastructure of energy delivery was designed over 60 years ago with the goal to be centralized. However, it is aging and is under-utilized, which will potentially limit the world's ability to achieve its energy objective. The lack of vibrant control on the grid makes it difficult to stop cascading power failure, and to achieve high penetration of renewable energy resources, such as wind and solar thus resulting in grid instability. A decentralized and distributed control mechanism implemented with a definite communication protocol solves the issues mentioned above. The electric power grid going into the future is expected to …
Bioremediation Of A Trichloroethene Dnapl Source Zone Utilizing A Partitioning Electron Donor - Field Implementation, Joseph Bartlett
Bioremediation Of A Trichloroethene Dnapl Source Zone Utilizing A Partitioning Electron Donor - Field Implementation, Joseph Bartlett
Electronic Theses and Dissertations
Trichloroethene (TCE) is a chlorinated volatile organic compound (CVOC) that can be found in industrial and household products. It is typically used as a solvent or degreaser. TCE can have detrimental health impacts and is known to be carcinogenic to humans. Federal and state regulatory drivers determine the need to assess and remediate soil and groundwater contaminated with CVOCs. There are many different methods for remediation; however, bioremediation has the ability to breakdown TCE all the way to harmless gasses (ethene and ethane). Bioremediation requires dechlorinating microbes (indigenous or augmented), electron donor (food source), and an electron acceptor (CVOCs). Electron …
Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash
Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash
Electronic Theses and Dissertations
This thesis presents three improvements in the UCF MANUS Assistive Robotic Manipulator's grasping abilities. Firstly, the robot can now grasp objects that are deformable, heavy and have uneven contact surfaces without undergoing slippage during robotic operations, e.g. paper cup, filled water bottle. This is achieved by installing a high precision non-contacting Laser sensor1 that runs with an algorithm that processes raw-input data from the sensor, registers smallest variation in the relative position of the object with respect to the gripper. Secondly, the robot can grasp objects that are as light and small as single cereal grain without deforming it. To …
Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby
Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby
Electronic Theses and Dissertations
Fog along roadways is a dangerous hazard that leads to crashes resulting from limited visibility. Low visibility gives drivers less time to react to potential obstacles that can suddenly appear and require immediate action. To solve this issue, early warning systems involving Dynamic Message Signs or other types of devices are used to alert drivers of the impending visibility condition so that they are prepared. This research focuses on testing the effectiveness of one form of warning systems to investigate how it impacts driver behavior in foggy conditions. To accomplish this objective, a simulation study is developed to test variables …
Techniques For Automated Parameter Estimation In Computational Models Of Probabilistic Systems, Faraz Hussain
Techniques For Automated Parameter Estimation In Computational Models Of Probabilistic Systems, Faraz Hussain
Electronic Theses and Dissertations
The main contribution of this dissertation is the design of two new algorithms for automatically synthesizing values of numerical parameters of computational models of complex stochastic systems such that the resultant model meets user-specified behavioral specifications. These algorithms are designed to operate on probabilistic systems – systems that, in general, behave differently under identical conditions. The algorithms work using an approach that combines formal verification and mathematical optimization to explore a model's parameter space. The problem of determining whether a model instantiated with a given set of parameter values satisfies the desired specification is first defined using formal verification terminology, …
Control Of Metal-Release And Tuberculation In A Silica-Laden Groundwater Distribution System On The Volcanic Island Of Lana'i, Samantha Myers
Control Of Metal-Release And Tuberculation In A Silica-Laden Groundwater Distribution System On The Volcanic Island Of Lana'i, Samantha Myers
Electronic Theses and Dissertations
A corrosion control study for two distinct water distribution systems (WDS) has been completed for the Pulama Lana'i Water Company (Pulama). This project evaluated the use of chemical inhibitors to control corrosion and tuberculation within the Manele Bay WDS and the Lana'i City WDS. Pulama provides water to a population of 3,100 residents and is considering incorporating alternative water supplies in the future. Hence, knowing baseline corrosion rates within the WDS was desired. Several groundwater wells feed each of the WDS's; however, water quality between wells varies. Well water supplied to the WDS's is generally of high quality, therefore, the …
Application Of Landfill Treatment Approaches For The Stabilization Of Municipal Solid Waste, Stephanie Bolyard
Application Of Landfill Treatment Approaches For The Stabilization Of Municipal Solid Waste, Stephanie Bolyard
Electronic Theses and Dissertations
This research focused on the fundamental requirements of stabilizing a mature landfill using three treatment approaches as well as the implications of discharging leachate organic matter (LOM) to wastewater treatment plants (WWTPs). Three treatment approaches aimed at removing releasable carbon and nitrogen from mature landfills including flushing with clean water, leachate recirculation with ex-situ chemical oxidation, and leachate recirculation with ex-situ chemical oxidation and in-situ aeration were evaluated. After extensive treatment of the waste in the flushing bioreactor (FB) scenarios, the overall biodegradable fraction was reduced relative to mature waste. Leachate quality improved for all FBs but through different mechanisms. …
Performance Evaluation Of Connectivity And Capacity Of Dynamic Spectrum Access Networks, Osama Al-Tameemi
Performance Evaluation Of Connectivity And Capacity Of Dynamic Spectrum Access Networks, Osama Al-Tameemi
Electronic Theses and Dissertations
Recent measurements on radio spectrum usage have revealed the abundance of under- utilized bands of spectrum that belong to licensed users. This necessitated the paradigm shift from static to dynamic spectrum access (DSA) where secondary networks utilize unused spectrum holes in the licensed bands without causing interference to the licensed user. However, wide scale deployment of these networks have been hindered due to lack of knowledge of expected performance in realistic environments and lack of cost-effective solutions for implementing spectrum database systems. In this dissertation, we address some of the fundamental challenges on how to improve the performance of DSA …
Broad Bandwidth Optical Frequency Combs From Low Noise, High Repetition Rate Semiconductor Mode-Locked Lasers, Anthony Klee
Broad Bandwidth Optical Frequency Combs From Low Noise, High Repetition Rate Semiconductor Mode-Locked Lasers, Anthony Klee
Electronic Theses and Dissertations
Mode-locked lasers have numerous applications in the areas of communications, spectroscopy, and frequency metrology. Harmonically mode-locked semiconductor lasers with external ring cavities offer a unique combination of benefits in that they can produce high repetition rate pulse trains with low timing jitter, achieve narrow axial mode linewidths, have the potential for entire monolithic integration on-chip, feature high wall-plug efficiency due to direct electrical pumping, and can be engineered to operate in different wavelength bands of interest. However, lasers based on InP/InGaAsP quantum well devices which operate in the important telecom C-band have thus far been relatively limited in bandwidth as …
Microscopic Safety Evaluation And Prediction For Special Expressway Facilities, Ling Wang
Microscopic Safety Evaluation And Prediction For Special Expressway Facilities, Ling Wang
Electronic Theses and Dissertations
Expressways are of great importance and serve as the backbone of a roadway system. One of the reasons why expressways increase travel speeds and provide high level of services is that limited access is provided to permit vehicles to enter or exit expressways. Entering and exiting of vehicles are accomplished through interchanges, which consist of several ramps, thus the spacing between ramps is important. A weaving segment might form when an on-ramp is closely followed by an off-ramp. The geometric design of ramps and the traffic behavior of weaving segments are different from other expressway segments. These differences result in …
Microgrid Control And Protection: Stability And Security, Morteza Keshavarztalebi
Microgrid Control And Protection: Stability And Security, Morteza Keshavarztalebi
Electronic Theses and Dissertations
When the microgrid disconnects from the main grid in response to, say, upstream disturbance or voltage fluctuation and goes to islanding mode, both voltage and frequency at all locations in the microgrid have to be regulated to nominal values in a short amount of time before the operation of protective relays. Motivated by this, we studied the application of intelligent pinning of distributed cooperative secondary control of distributed generators in islanded microgrid operation in a power system. In the first part, the problem of single and multi-pinning of distributed cooperative secondary control of DGs in a microgrid is formulated. It …
A Holistic Framework For Effective Engineering Leadership Development Using 3d Virtual World Simulation, Hamed Almalki
A Holistic Framework For Effective Engineering Leadership Development Using 3d Virtual World Simulation, Hamed Almalki
Electronic Theses and Dissertations
Problems associated with the limited success of traditional engineering leadership development are the absence of embedded real-life industry case studies in leadership development and incorrect applications of leadership strategies in the various contexts. Though recommended programs for enhancing leadership development exist, they lack an examined framework, especially when it comes to leadership development of undergraduate engineering students. In this research effort, the impact of a framework using 3D virtual world simulation and the 4-D Leadership System to enhance the leadership abilities of undergraduate engineering students at the individual and team levels based on industrial leadership case studies was investigated. The …
Synthesis And Characterization Of Stable And Metastable Phases In Ni- And Fe-Based Alloy Systems By Mechanical Alloying, Ahmed Al-Joubori
Synthesis And Characterization Of Stable And Metastable Phases In Ni- And Fe-Based Alloy Systems By Mechanical Alloying, Ahmed Al-Joubori
Electronic Theses and Dissertations
Mechanical Alloying (MA) is a process that involves repeated cold welding, fracturing and rewelding of powder particles in a high-energy ball mill and has been used extensively to synthesize both stable (equilibrium) and metastable phases in a number of alloy systems. This is due to its ability to achieve many effects simultaneously, viz., reduction in grain size, introduction of a variety of crystal defects, disordering of the lattice, and modifying the crystal structures of materials; all these allowing alloying and phase transformations to occur in powders. In this Dissertation, we have synthesized a number of different alloy phases in Ni- …
Enhanced Hardware Security Using Charge-Based Emerging Device Technology, Yu Bi
Enhanced Hardware Security Using Charge-Based Emerging Device Technology, Yu Bi
Electronic Theses and Dissertations
The emergence of hardware Trojans has largely reshaped the traditional view that the hardware layer can be blindly trusted. Hardware Trojans, which are often in the form of maliciously inserted circuitry, may impact the original design by data leakage or circuit malfunction. Hardware counterfeiting and IP piracy are another two serious issues costing the US economy more than $200 billion annually. A large amount of research and experimentation has been carried out on the design of these primitives based on the currently prevailing CMOS technology. However, the security provided by these primitives comes at the cost of large overheads mostly …
Deposition And Characterization Studies Of Boron Carbon Nitride (Bcn) Thin Films Prepared By Dual Target Sputtering, Adithya Prakash
Deposition And Characterization Studies Of Boron Carbon Nitride (Bcn) Thin Films Prepared By Dual Target Sputtering, Adithya Prakash
Electronic Theses and Dissertations
As complementary metal-oxide semiconductor (CMOS) devices shrink to smaller size, the problems related to circuit performance such as critical path signal delay are becoming a pressing issue. These delays are a result of resistance and capacitance product (RC time constant) of the interconnect circuit. A novel material with reduced dielectric constants may compromise both the thermal and mechanical properties that can lead to die cracking during package and other reliability issues. Boron carbon nitride (BCN) compounds have been expected to combine the excellent properties of boron carbide (B4C), boron nitride (BN) and carbon nitride (C3N4), with their properties adjustable, depending …
Phase Transformation And Growth Kinetics In Reaction Zone Between Uranium Alloy And Zirconium Diffusion Barrier, Young Joo Park
Phase Transformation And Growth Kinetics In Reaction Zone Between Uranium Alloy And Zirconium Diffusion Barrier, Young Joo Park
Electronic Theses and Dissertations
U-10wt.%Mo (U10Mo) alloy as a part of monolithic fuel system is being developed under Material Management and Minimization Reactor Conversion (MMMRC) program, tasked with replacing high-enriched uranium (HEU) fuel with low-enriched uranium (LEU) fuel in civilian research and test reactors. Use of U10Mo fuel alloy entails a Zr diffusion barrier to avoid the undesirable interdiffusion and reactions between the U10Mo and Al-alloy cladding. To better understand the interaction between these fuel system constituents, microstructural development and diffusion kinetics in U-Mo-Zr, U-Zr and fuel plate assembly processed by co-rolling and hot isostatic pressing (HIP) were investigated using a variety of analytical …
Design And Characterization Of System Level Electrostatic Discharge (Esd) Protection Solutions, Yunfeng Xi
Design And Characterization Of System Level Electrostatic Discharge (Esd) Protection Solutions, Yunfeng Xi
Electronic Theses and Dissertations
Electrostatic Discharges (ESD) are one of the main reliability threats in modern electronics. Design, implementation, and characterization of ESD and transient protection of these modern electronics are increasingly challenging due to the process, packaging and cost constraints. Growing communication between ‘objects’ to be sensed and controlled remotely is creating opportunities for greater integration with computer systems, resulting in improved efficiency, accuracy and economic benefits across existing and emerging network infrastructures. This tendency is driving an expansion in data communication as well as industrial applications environment. To keep up with the interconnectivity expansion, the industry requires new devices to support more …
A New Six Sigma Implementation Approach For Power Generation Gas Turbines Repair Process Development, Somesh Ghunakikar
A New Six Sigma Implementation Approach For Power Generation Gas Turbines Repair Process Development, Somesh Ghunakikar
Electronic Theses and Dissertations
Power Generation gas turbines used for heavy duty application mainly constitutes three modules; compressor, combustion and turbine. Typically, all these parts are designed by OEM companies for specific number of hours and cycles (also known as starts) before they become dysfunctional. In addition, Gas Turbine (GT) also have intended repair interval depending upon the type of part application and anticipated damages during service operation. Thus, GT parts need inspections and repair (overhaul) after certain operating hours in order to recondition them so that they can be fit for reoperation to produce power. In this dissertation, a unique six sigma DFSS …
Remote Sensing Of Coastal Wetlands: Long Term Vegetation Stress Assessment And Data Enhancement Technique, Subrina Tahsin
Remote Sensing Of Coastal Wetlands: Long Term Vegetation Stress Assessment And Data Enhancement Technique, Subrina Tahsin
Electronic Theses and Dissertations
Apalachicola Bay in the Florida panhandle is home to a rich variety of salt water and freshwater wetlands but unfortunately is also subject to a wide range of hydrologic extreme events. Extreme hydrologic events such as hurricanes and droughts continuously threaten the area. The impact of hurricane and drought on both fresh and salt water wetlands was investigated over the time period from 2000 to 2015 in Apalachicola Bay using spatio-temporal changes in the Landsat based NDVI. Results indicate that salt water wetlands were more resilient than fresh water wetlands. Results also suggest that in response to hurricanes, the coastal …
Fundamental Understanding Of Interactions Among Flow, Turbulence, And Heat Transfer In Jet Impingement Cooling, Md. Jahed Hossain
Fundamental Understanding Of Interactions Among Flow, Turbulence, And Heat Transfer In Jet Impingement Cooling, Md. Jahed Hossain
Electronic Theses and Dissertations
The flow physics of impinging jet is very complex and is not fully understood yet. The flow field in an impingement problem comprised of three different distinct regions: a free jet with a potential core, a stagnation region where the velocity goes to zero as the jet impinges onto the wall and a creation of wall jet region where the boundary layer grows radially outward after impinging. Since impingement itself is a broad topic, effort is being made in the current study to narrow down on three particular geometric configurations (a narrow wall, an array impingement configuration and a curved …
Shock Tube And Mid-Infrared Laser Absorption Measurements Of Ignition Delay Times And Species Time-Histories, Batikan Koroglu
Shock Tube And Mid-Infrared Laser Absorption Measurements Of Ignition Delay Times And Species Time-Histories, Batikan Koroglu
Electronic Theses and Dissertations
Energy consumption has increased dramatically as the world advances and becomes more industrialized. Over the next twenty five years, the U.S. Department of Energy expects the energy demand to increase by 29% with majority of the new energy coming from natural gas (methane). Another promising fuel source for power generation and transportation is the biofuels. The biofuel use in the US is shown to have increased substantially in the last decade. There are serious environmental concerns associated with greenhouse (e.g. carbon-dioxide) and toxic gas emissions (e.g. nitrogen oxides and aldehydes such as propanal) due to deriving energy from natural gas …