Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Electrical and Computer Engineering (1177)
- Civil and Environmental Engineering (668)
- Mechanical Engineering (654)
- Physical Sciences and Mathematics (633)
- Electrical and Electronics (400)
-
- Civil Engineering (373)
- Computer Engineering (341)
- Physics (298)
- Electromagnetics and Photonics (292)
- Optics (270)
- Materials Science and Engineering (267)
- Computer Sciences (249)
- Operations Research, Systems Engineering and Industrial Engineering (249)
- Biomedical Engineering and Bioengineering (229)
- Chemical Engineering (229)
- Industrial Engineering (216)
- Environmental Engineering (188)
- Power and Energy (111)
- Aerospace Engineering (106)
- Transportation Engineering (82)
- Bioresource and Agricultural Engineering (73)
- Life Sciences (70)
- Environmental Sciences (58)
- Biomechanical Engineering (53)
- Medicine and Health Sciences (49)
- Engineering Science and Materials (47)
- Biomechanics and Biotransport (46)
- Social and Behavioral Sciences (46)
- Water Resource Management (44)
- Institution
- Keyword
-
- Daniel Felix Ritchie School of Engineering and Computer Science (332)
- Electrical and Computer Engineering (90)
- Mechanical and Materials Engineering (88)
- Machine learning (67)
- Simulation (65)
-
- Modeling (38)
- Computer vision (37)
- Optimization (32)
- Renewable energy (27)
- Additive manufacturing (26)
- Artificial intelligence (26)
- Computer Science (26)
- Deep learning (26)
- Computational fluid dynamics (22)
- Robotics (22)
- CFD (20)
- Optics (20)
- Finite element analysis (18)
- Remote sensing (18)
- Biomechanics (17)
- Data mining (17)
- MEMS (17)
- Machine Learning (17)
- Heat transfer (16)
- Nonlinear optics (16)
- Classification (15)
- Diffusion (15)
- Microstructure (15)
- Nanoparticles (15)
- Corrosion (14)
- Publication Year
Articles 3391 - 3420 of 4180
Full-Text Articles in Engineering
Ultra-Wideband Orthogonal Frequency Coded Saw Correlators, Daniel Gallagher
Ultra-Wideband Orthogonal Frequency Coded Saw Correlators, Daniel Gallagher
Electronic Theses and Dissertations
Ultra-wideband (UWB) communication new technology with ability to share the FCC allocated frequency spectrum, large channel capacity and data rate, simple transceiver architecture and high performance in noisy environments. Such communication advantages have paved the way for emerging wireless technologies such as wireless high definition video streaming, wireless sensor networks and more. This thesis examines orthogonal frequency coded surface acoustic wave (SAW) correlators for use in advanced UWB communication systems. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for UWB spreading of data. The use of OFC spectrally spreads a PN sequence beyond that of CDMA because …
Simulation And Study Of The Stokes Vector In A Precipitating Atmosphere, Ian Adams
Simulation And Study Of The Stokes Vector In A Precipitating Atmosphere, Ian Adams
Electronic Theses and Dissertations
Precipitation is a dominating quantity in microwave radiometry. The large emission and scattering signals of rain and ice, respectively, introduce large contributions to the measured brightness temperature. While this allows for accurate sensing of precipitation, it also results in degraded performance when retrieving other geophysical parameters, such as near-surface ocean winds. In particular, the retrieval of wind direction requires precise knowledge of polarization, and nonspherical particles can result in a change in the polarization of incident radiation. The aim of this dissertation is to investigate the polarizing effects of precipitation in the atmosphere, including the existence of a precipitation signal …
Assessment Of The Safety Benefits Of Vms And Vsl Using The Ucf Driving Simulator, Cristina Dos Santos
Assessment Of The Safety Benefits Of Vms And Vsl Using The Ucf Driving Simulator, Cristina Dos Santos
Electronic Theses and Dissertations
Researchers at the University of Central Florida (UCF) have been working during the past few years on different strategies to improve freeway safety in real-time. An ongoing research at UCF has investigated crash patterns that occurred on a stretch of Interstate-4 located in Orlando, FL and created statistical models to predict in real-time the likelihood of a crash in terms of time and space. The models were then tested using PARAMICS micro-simulation and different strategies that would reduce the risk of crashes were suggested. One of the main recommended strategies was the use of Variable Speed Limits (VSL) which intervenes …
Learning Geometry-Free Face Re-Lighting, Thomas Brendan Moore
Learning Geometry-Free Face Re-Lighting, Thomas Brendan Moore
Electronic Theses and Dissertations
The accurate modeling of the variability of illumination in a class of images is a fundamental problem that occurs in many areas of computer vision and graphics. For instance, in computer vision there is the problem of facial recognition. Simply, one would hope to be able to identify a known face under any illumination. On the other hand, in graphics one could imagine a system that, given an image, the illumination model could be identified and then used to create new images. In this thesis we describe a method for learning the illumination model for a class of images. Once …
Modeling,Design,And Characterization Of Monolithic Bi-Directional Power Semiconductor Switch, Yue Fu
Modeling,Design,And Characterization Of Monolithic Bi-Directional Power Semiconductor Switch, Yue Fu
Electronic Theses and Dissertations
Bidirectional power switching devices are needed in many power management applications, particularly in lithium-ion battery protection circuitry. A monolithic bidirectional power switch fabricated with a simplified CMOS technology is introduced in this dissertation. Throughout the design process, ISE TCAD tool plays an important role. Design variables are carefully analyzed to improve the device performance or yield the best trade off. Optimization is done with the help of TCAD simulation and theoretical calculations. The device has been successfully fabricated using simplified 0.5 micron CMOS process. The experimental result shows a breakdown voltage of 25V. Due to the interdigitated source to source …
Investigation Of Reactively Sputtered Silicon Carbon Boron Nitride (Sicbn) Thin Films For High Temperature Applications, Arun Vijayakumar
Investigation Of Reactively Sputtered Silicon Carbon Boron Nitride (Sicbn) Thin Films For High Temperature Applications, Arun Vijayakumar
Electronic Theses and Dissertations
The increasing demand for efficient energy systems in the last decade has brought about the development of advanced sensor systems that utilize advance detection methods to help in preventive maintenance of these essential systems. These usually are needed in hard to access environments where conditions are extreme and unfit for human interaction. Thin film based sensors deposited directly on the surfaces exposed to harsh environments can serve as ideal means of measuring the temperature of the component during operation. They provide the basic advantage of proximity to the surface and hence accurate measurement of the surface temperature. The low mass …
On Advanced Template-Based Interpretation As Applied To Intention Recognition In A Strategic Environment, Cameron Akridge
On Advanced Template-Based Interpretation As Applied To Intention Recognition In A Strategic Environment, Cameron Akridge
Electronic Theses and Dissertations
An area of study that has received much attention over the past few decades is simulations involving threat assessment in military scenarios. Recently, much research has emerged concerning the recognition of troop movements and formations in non-combat simulations. Additionally, there have been efforts towards the detection and assessment of various types of malicious intentions. One such work by Akridge addressed the issue of Strategic Intention Recognition, but fell short in the detection of tactics that it could not detect without somehow manipulating the environment. Therefore, the aim of this thesis is to address the problem of recognizing an opponent's intent …
Integrated Topologies And Digital Control For Satellite Power Management And Distribution Systems, Hussam Al-Atrash
Integrated Topologies And Digital Control For Satellite Power Management And Distribution Systems, Hussam Al-Atrash
Electronic Theses and Dissertations
This work is focused on exploring advanced solutions for space power management and distribution (PMAD) systems. As spacecraft power requirements continue to increase, paralleled by the pressures for reducing cost and overall system weight, power electronics engineers will continue to face major redesigns of the space power systems in order to meet such challenges. Front-end PMAD systems, used to interface the solar sources and battery backup to the distribution bus, need to be designed with increased efficiency, reliability, and power density. A new family of integrated single-stage power converter structures is introduced here. This family allows the interface and control …
Reviewing The Effects Of Alternative Fuels, Average Speed And Idling Time On Emissions From Orange County School Bus Fleet, Ali Bayat
Electronic Theses and Dissertations
Orange County, FL has been experiencing ozone concentrations in the past several years which in some cases exceeded the national and state standards. The high concentration of ground level ozone can cause a variety of health problems including chest pain, coughing, throat irritation, and congestion or it can worsen bronchitis, emphysema, and asthma. Other effects include reduction of agricultural crop and commercial forest yields, lower growth and survivability of tree seedlings, and higher susceptibility of plant to diseases, pests and other stresses such as harsh weather. The ozone generation rate is directly related to the ambient concentration of nitrogen oxides …
Design And Implementation Of A Hardware Level Content Networking Front End Device, Jeremy Layne Buboltz
Design And Implementation Of A Hardware Level Content Networking Front End Device, Jeremy Layne Buboltz
Electronic Theses and Dissertations
The bandwidth and speed of network connections are continually increasing. The speed increase in network technology is set to soon outpace the speed increase in CMOS technology. This asymmetrical growth is beginning to causing software applications that once worked with then current levels of network traffic to flounder under the new high data rates. Processes that were once executed in software now have to be executed, partially if not wholly in hardware. One such application that could benefit from hardware implementation is high layer routing. By allowing a network device to peer into higher layers of the OSI model, the …
Spacecraft Loads Predictionvia Sensitivity Analysis And Optimization, Tom Braswell
Spacecraft Loads Predictionvia Sensitivity Analysis And Optimization, Tom Braswell
Electronic Theses and Dissertations
Discrepancies between the predicted responses of a finite element analysis (FEA) and reference data from test results arise for many reasons. Some are due to measurement errors, such as inaccurate sensors, noise in the acquisition system or environmental effects. Some are due to analyst errors precipitated by a lack of familiarity with the modeling or solver software. Still others are introduced by uncertainty in the governing physical relations (linear versus non-linear behavior), boundary conditions or the element material/geometrical properties. It is the uncertainty effects introduced by this last group that this study seeks to redress. The objective is the obtainment …
Dimesionality Aspects Of Nano Micro Integrated Metal Oxide Based Early Stage Leak Detection Room Temperature Hydrogen Sensor, Sameer Arun Deshpande
Dimesionality Aspects Of Nano Micro Integrated Metal Oxide Based Early Stage Leak Detection Room Temperature Hydrogen Sensor, Sameer Arun Deshpande
Electronic Theses and Dissertations
Detection of explosive gas leaks such as hydrogen (H2) becomes key element in the wake of counter-terrorism threats, introduction of hydrogen powered vehicles and use of hydrogen as a fuel for space explorations. In recent years, a significant interest has developed on metal oxide nanostructured sensors for the detection of hydrogen gas. Gas sensors properties such as sensitivity, selectivity and response time can be enhanced by tailoring the size, the shape, the structure and the surface of the nanostructures. Sensor properties (sensitivity, selectivity and response time) are largely modulated by operating temperature of the device. Issues like instability of nanostructures …
Four Terminal Junction Field-Effect Transistor Model For Computer-Aided Design, Hao Ding
Four Terminal Junction Field-Effect Transistor Model For Computer-Aided Design, Hao Ding
Electronic Theses and Dissertations
A compact model for four-terminal (independent top and bottom gates) junction field-effect transistor (JFET) is presented in this dissertation. The model describes the steady-state characteristics with a unified equation for all bias conditions that provides a high degree of accuracy and continuity of conductance, which are important for predictive analog circuit simulations. It also includes capacitance and leakage equations. A special capacitance drop-off phenomenon at the pinch-off region is studies and modeled. The operations of the junction fieldeffect transistor (JFET) with an oxide top-gate and full oxide isolation are analyzed, and a semi-physical compact model is developed. The effects of …
High Pressure Testing Of Composite Solid Rocket Propellant Mixtures: Burner Facility Characterization, Rodolphe Valentin Carro
High Pressure Testing Of Composite Solid Rocket Propellant Mixtures: Burner Facility Characterization, Rodolphe Valentin Carro
Electronic Theses and Dissertations
Much Research on composite solid propellants has been performed over the past few decades and much progress has been made, yet many of the fundamental processes are still unknown, and the development of new propellants remains highly empirical. Ways to enhance the performance of solid propellants for rocket and other applications continue to be explored experimentally, including the effects of various additives and the impact of fuel and oxidizer particle sizes on burning behavior. One established method to measure the burning rate of composite propellant mixtures in a controlled laboratory setting is to use a constant-volume pressure vessel, or strand …
Optimizing The High Dynamic Range Imaging Pipeline, Ahmet Oguz Akyuz
Optimizing The High Dynamic Range Imaging Pipeline, Ahmet Oguz Akyuz
Electronic Theses and Dissertations
High dynamic range (HDR) imaging is a rapidly growing field in computer graphics and image processing. It allows capture, storage, processing, and display of photographic information within a scene-referred framework. The HDR imaging pipeline consists of the major steps an HDR image is expected to go through from capture to display. It involves various techniques to create HDR images, pixel encodings and file formats for storage, tone mapping for display on conventional display devices and direct display on HDR capable screens. Each of these stages have important open problems, which need to be addressed for a smoother transition to an …
Signal Processing Of An Ecg Signal In The Presence Of A Strong Static Magnetic Field, Aditya Gupta
Signal Processing Of An Ecg Signal In The Presence Of A Strong Static Magnetic Field, Aditya Gupta
Electronic Theses and Dissertations
This dissertation addresses the problem of elevation of the T wave of an electrocardiogram (ECG) signal in the magnetic resonance imaging (MRI). In the MRI, due to the strong static magnetic field the interaction of the blood flow with this strong magnetic field induces a voltage in the body. This voltage appears as a superimposition at the locus of the T wave of the ECG signal. This looses important information required by the doctors to interpret the ST segment of the ECG and detect diseases such as myocardial infarction. This dissertation aims at finding a solution to the problem of …
Studies Of A Quantum Scheduling Algorithm And On Quantum Error Correction, Feng Lu
Studies Of A Quantum Scheduling Algorithm And On Quantum Error Correction, Feng Lu
Electronic Theses and Dissertations
Quantum computation has been a rich field of study for decades because it promises possible spectacular advances, some of which may run counter to our classically rooted intuitions. At the same time, quantum computation is still in its infancy in both theoretical and practical areas. Efficient quantum algorithms are very limited in number and scope; no real breakthrough has yet been achieved in physical implementations. Grover's search algorithm can be applied to a wide range of problems; even problems not generally regarded as searching problems can be reformulated to take advantage of quantum parallelism and entanglement leading to algorithms which …
Network Performance Management Using Application-Centric Key Performance Indicators, Susan Mcgill
Network Performance Management Using Application-Centric Key Performance Indicators, Susan Mcgill
Electronic Theses and Dissertations
The Internet and intranets are viewed as capable of supplying "Anything, Anywhere, Anytime" and e-commerce, e-government, e-community, and military C4I are now deploying many and varied applications to serve their needs. Network management is currently centralized in operations centers. To assure customer satisfaction with the network performance they typically plan, configure and monitor the network devices to insure an excess of bandwidth, that is overprovision. If this proves uneconomical or if complex and poorly understood interactions of equipment, protocols and application traffic degrade performance creating customer dissatisfaction, another more application-centric, way of managing the network will be needed. This research …
Learning Human Behavior From Observation For Gaming Applications, Christopher Moriarty
Learning Human Behavior From Observation For Gaming Applications, Christopher Moriarty
Electronic Theses and Dissertations
The gaming industry has reached a point where improving graphics has only a small effect on how much a player will enjoy a game. One focus has turned to adding more humanlike characteristics into computer game agents. Machine learning techniques are being used scarcely in games, although they do offer powerful means for creating humanlike behaviors in agents. The first person shooter (FPS), Quake 2, is an open source game that offers a multi-agent environment to create game agents (bots) in. This work attempts to combine neural networks with a modeling paradigm known as context based reasoning (CxBR) to create …
Exploring The Potential Of Combining Ramp Metering And Variable Speed Limit Strategies For Alleviating Real-Time Crash Risk On Urban Freeways, Kirolos Maged Haleem
Exploring The Potential Of Combining Ramp Metering And Variable Speed Limit Strategies For Alleviating Real-Time Crash Risk On Urban Freeways, Kirolos Maged Haleem
Electronic Theses and Dissertations
Research recently conducted at the University of Central Florida involving crashes on Interstate-4 in Orlando, Florida has led to the creation of new statistical and neural networks models that are capable of determining the crash risk on the freeway (Abdel-Aty et al., 2004; 2005, Pande and Abdel-Aty, 2006). These models are able to calculate rear-end and lane-change crash risks along the freeway in real-time through the use of static information at various locations along the freeway as well as real-time traffic data obtained by loop detectors. Since these models use real-time traffic data, they are capable of calculating rear-end and …
Urban Infilling Impacts On Florida Solid Waste Facilities, Ravi Chander Nalamothu
Urban Infilling Impacts On Florida Solid Waste Facilities, Ravi Chander Nalamothu
Electronic Theses and Dissertations
Increasing urbanization in the US is leading to development or re-development of lands adjacent to solid waste facilities and these lands are being considered for residential communities and commercial projects. Thus, the potential for nuisance complaints against the pre-existing solid waste facility operations has become an increasing reality. The objective of this study was to develop a methodology to gather scientific and quantifiable data related to potential nuisances caused by landfills to determine setbacks and buffer zones near landfill and transfer station operations. Appropriate recommendations for these setbacks were made from case studies conducted at two landfills in Florida. The …
Mechanisms Of Lifetime Improvement In Thermal Barrier Coatings With Hf And/Or Y Modification Of Cmsx-4 Superalloy Substrates, Jing Liu
Electronic Theses and Dissertations
In modern turbine engines for propulsion and energy generation, thermal barrier coating (TBCs) protect hot-section blades and vanes, and play a critical role in enhancing reliability, durability and operation efficiency. In this study, thermal cyclic lifetime and microstructural degradation of electron beam physical vapor deposited (EB-PVD) Yttria Stabilized Zirconia (YSZ) with (Ni,Pt)Al bond coat and Hf- and/or Y- modified CMSX-4 superalloy substrates were examined. Thermal cyclic lifetime of TBCs was measured using a furnace thermal cycle test that consisted of 10-minute heat-up, 50-minute dwell at 1135C, and 10-minute forced-air-quench. TBC lifetime was observed to improve from 600 cycles to over …
An Algorithm For Determining Satellite Attitude By Comparing Physical Feature Models To Edges Detected In Satellite Or Ground-Based Telescope Imagery, Eric Brian Reinhart
An Algorithm For Determining Satellite Attitude By Comparing Physical Feature Models To Edges Detected In Satellite Or Ground-Based Telescope Imagery, Eric Brian Reinhart
Electronic Theses and Dissertations
This thesis discusses the development and performance of an algorithm created to calculate satellite attitude based on the comparison of satellite "physical feature" models to information derived from edge detection performed on imagery of the satellite. The quality of this imagery could range from the very clear, close-up imagery that may come from an unmanned satellite servicing mission to the faint, unclear imagery that may come from a ground-based telescope investigating a satellite anomaly. Satellite "physical feature" models describe where an edge is likely to appear in an image. These are usually defined by physical edges on the structure of …
Fate Of Nitrogen And Phosphorus Species From A Black And Goldtm Nugget Mix In A Laboratoy Column Simulated Septic Tank Drainfiel, Timir Shah
Electronic Theses and Dissertations
The presence of nitrates and phosphorus in ground water is a worldwide problem. A septic tank with drainfield that is conventionally designed does not typically remove nitrogen in the form of nitrates. The main risks are in "Blue baby" syndrome and suspected carcinogenic effect of nitrates on humans and the nutrient enrichment of receiving waters. In some areas nitrate and phosphorus removal are essentially required. Thus the information in this report concentrates on using media in the drainfield for the removal of nitrogen and phosphorus. Extensive work has been conducted in the past few decades in order to find suitable …
Image-Space Approach To Real-Time Realistic Rendering, Musawir Shah
Image-Space Approach To Real-Time Realistic Rendering, Musawir Shah
Electronic Theses and Dissertations
One of the main goals of computer graphics is the fast synthesis of photorealistic image of virtual 3D scenes. The work presented in this thesis addresses this goal of speed and realism. In real-time realistic rendering, we encounter certain problems that are difficult to solve in the traditional 3-dimensional geometric space. We show that using an image-space approach can provide effective solutions to these problems. Unlike geometric space algorithms that operate on 3D primitives such as points, edges, and polygons, image-space algorithms operate on 2D snapshot images of the 3D geometric data. Operating in image-space effectively decouples the geometric complexity …
An Economic Framework For Resource Management And Pricing In Wireless Networks With Competitive Service Providers, Shamik Sengupta
An Economic Framework For Resource Management And Pricing In Wireless Networks With Competitive Service Providers, Shamik Sengupta
Electronic Theses and Dissertations
A paradigm shift from static spectrum allocation to dynamic spectrum access (DSA) is becoming a reality due to the recent advances in cognitive radio, wide band spectrum sensing, and network aware real--time spectrum access. It is believed that DSA will allow wireless service providers (WSPs) the opportunity to dynamically access spectrum bands as and when they need it. Moreover, due to the presence of multiple WSPs in a region, it is anticipated that dynamic service pricing would be offered that will allow the end-users to move from long-term service contracts to more flexible short-term service models. In this research, we …
A Hybrid Routing Protocol For Communications Among Nodes Withhigh Relative Speed In Wireless Mesh Networks, Nikolaos Peppas
A Hybrid Routing Protocol For Communications Among Nodes Withhigh Relative Speed In Wireless Mesh Networks, Nikolaos Peppas
Electronic Theses and Dissertations
Wireless mesh networks (WMN) is a new promising wireless technology which uses already available hardware and software components. This thesis proposes a routing algorithm for military applications. More specifically, a specialized scenario consisting of a network of flying Unmanned Aerial Vehicles (UAVs) executing reconnaissance missions is investigated. The proposed routing algorithm is hybrid in nature and uses both reactive and proactive routing characteristics to transmit information. Through simulations run on a specially built stand alone simulator, based on Java, packet overhead, delivery ratio and latency metrics were monitored with respect to varying number of nodes, node density and mobility. The …
Behavior Of Variable-Length Genetic Algorithms Under Random Selection, Harold Stringer
Behavior Of Variable-Length Genetic Algorithms Under Random Selection, Harold Stringer
Electronic Theses and Dissertations
In this work, we show how a variable-length genetic algorithm naturally evolves populations whose mean chromosome length grows shorter over time. A reduction in chromosome length occurs when selection is absent from the GA. Specifically, we divide the mating space into five distinct areas and provide a probabilistic and empirical analysis of the ability of matings in each area to produce children whose size is shorter than the parent generation's average size. Diversity of size within a GA's population is shown to be a necessary condition for a reduction in mean chromosome length to take place. We show how a …
Evaluating The Impact Of Oocea S Dynamic Message Signs (Dms) On Travelers Experience Using The Pre-Deployment Survey, John Hill Rogers
Evaluating The Impact Of Oocea S Dynamic Message Signs (Dms) On Travelers Experience Using The Pre-Deployment Survey, John Hill Rogers
Electronic Theses and Dissertations
The purpose of this thesis was to evaluate the impact of dynamic message signs (DMS) on the Orlando-Orange County Expressway Authority (OOCEA) toll road network using the Pre-Deployment DMS Survey (henceforth referred to as "pre-deployment survey"). DMS are electronic traffic signs used on roadways to give travelers information about travel times, traffic congestion, accidents, disabled vehicles, AMBER alerts, and special events. The particular DMS referred to in this study are large rectangular signs installed over the travel lanes and these are not the portable trailer mount signs. The OOCEA is currently in the process of adding several fixed DMS on …
Gate Stack And Channel Engineering: Study Of Metal Gates And Ge Channel Devices, Ravi Todi
Gate Stack And Channel Engineering: Study Of Metal Gates And Ge Channel Devices, Ravi Todi
Electronic Theses and Dissertations
The continued scaling of device dimensions in complementary metal oxide semiconductor (CMOS) technology within the sub-100 nm region requires an alternative high dielectric constant (high-k) oxide layer to counter high tunneling leakage currents, a metallic gate electrode to address polysilicon depletion, boron penetration and high polysilicon sheet resistance, and high mobility channel materials to boost the CMOS performance. Metal gates can also offer improved thermal and chemical stability, but their use requires that we improve our understanding of how the metal alloy phase, crystallographic orientation, and composition affect the electronic properties of the metal alloy-oxide interface. To replace n++ and …