Engineering Commons^™

Flexsar Bistatic And Monostatic Circular Sar Collection, Chad Knight, Mark Jensen, Trevor Jewkes, Jacob Gunther

Space Dynamics Laboratory Publications

Bistatic SAR data has advantages and disadvantages compared to monostatic data. This papers examines a combined bistatic and monostatic SAR data collection. The airborne platform used a monostatic radar system with two transmit and two receive channels in a pulsed spotlight mode. Another receive-only system was placed on an elevated mountaintop. The mountaintop receive system had two receive channels. The airborne asset flew in a full circle around several targets, exercising a large range of bistatic geometries. Various SAR modes were collected, including single-channel, quad-channel, and along-track interferometry (ATI) data for monostatic and bistatic modalities. This paper focuses on the …

A Data-Driven Approach For Benchmarking Energy Efficiency Of Warehouse Buildings, Wee Leong Lee, Kar Way Tan, Zui Young Lim

Research Collection School Of Computing and Information Systems

This study proposes adata-driven approach for benchmarking energy efficiency of warehouse buildings.Our proposed approach provides an alternative to the limitation of existingbenchmarking approaches where a theoretical energy-efficient warehouse was usedas a reference. Our approach starts by defining the questions needed to capturethe characteristics of warehouses relating to energy consumption. Using an existingdata set of warehouse building containing various attributes, we first cluster theminto groups by their characteristics. The warehouses characteristics derivedfrom the cluster assignments along with their past annual energy consumptionare subsequently used to train a decision tree model. The decision tree providesa classification of what factors contribute to different …

Cryptography And Data Security In Cloud Computing, Zheng Yan, Robert H. Deng, Vijay Varadharajan

Research Collection School Of Computing and Information Systems

Cloud computing offers a new way of services by re-arranging various resources and providing them to users based on their demands. It also plays an important role in the next generation mobile networks and services (5G) and Cyber-Physical and Social Computing (CPSC). Storing data in the cloud greatly reduces storage burden of users and brings them access convenience, thus it has become one of the most important cloud services. However, cloud data security, privacy and trust become a crucial issue that impacts the success of cloud computing and may impede the development of 5G and CPSC. First, storing data at …

Discovering Your Selling Points: Personalized Social Influential Tags Exploration, Yuchen Li, Kian-Lee Tan, Ju Fan, Dongxiang Zhang

Research Collection School Of Computing and Information Systems

Social influence has attracted significant attention owing to the prevalence of social networks (SNs). In this paper, we study a new social influence problem, called personalized social influential tags exploration (PITEX), to help any user in the SN explore how she influences the network. Given a target user, it finds a size-k tag set that maximizes this user’s social influence. We prove the problem is NP-hard to be approximated within any constant ratio. To solve it, we introduce a sampling-based framework, which has an approximation ratio of 1−ǫ 1+ǫ with high probabilistic guarantee. To speedup the computation, we devise more …

Symbol Salience Affects Change Detection Performance In General Aviation Weather Displays, Adam A. Hruszczyk

Theses and Dissertations

General aviation pilots perform many tasks during a flight such as navigating a route, performing 'see and avoid', operating the radio and navigational instruments, viewing charts and approach plates, and scanning and interpreting their flight instruments. In addition to these tasks, pilots may utilize a cockpit weather presentation to monitor weather information for areas along the route of flight. Due to the complexity of most modern weather displays, information changes may go unnoticed. The objective of this study was to examine how saliency characteristics such as line color, thickness, and orientation affected an observer’s change detection performance and response time. …

Exploring Usability In Web-Based Aviation Weather: An Assessment Of The Aviation Weather Center Website, Benjamin Remy

Theses and Dissertations

To provide a starting point for usability research in the area of online aviation weather, we performed a two-part usability study of the popular Aviation Weather Center website for general aviation users. The first part of the study utilized the System Usability Scale to examine different types of weather information as used by a general aviation pilot on a VFR cross-country flight and compare the usability of the information to an existing benchmark. No scores were significantly less than the benchmark, but the ordering of weather information by usability score provided valuable insight into the relationship between usability and pilot …

The Effects Of Laser Eye Protection On Color Recognition And Discrimination, Sherisse Melanie Pierre

Theses and Dissertations

The number of reported laser strikes on aircraft has increased over the years. Laser strikes pose a threat to safety and thus, warrant attention and mitigation efforts. Laser Eye Protection (LEP) is one mitigation method available to pilots; however, LEP can affect a person’s color vision. When wearing the LEP pilots should be able to retain sufficient color recognition and discrimination abilities. This exploratory study investigates the effect of LEP on color recognition and discrimination of four colors, red, blue, green, and amber, using a sample of 90 participants. When using the LEP the majority of participants were able to …

Single Waypoint Zem/Zev Based Closed-Loop Controller Design For Rendezvous With A Rotating Target, Armando Alvarez Rolins

Theses and Dissertations

The research presented in this thesis addresses a very specific kind of autonomous rendezvous procedure between two spacecraft in close proximity, namely that in which the chaser object is attempting to dock at a location on a rotating target which is tracing a circle perpendicular to the axis of rotation. The approaches that have been mentioned in literature which focus on this specific condition make use of offline optimization algorithms to plot the trajectory of the chaser and use closed-loop control to follow that trajectory. This method is computationally demanding and does not allow for feedback in the desired boundary …

Takeoff And Landing Distance Measurement: An Evaluation Of Laser Altimetry For The Collection Of Absolute Aircraft Altitude, Christopher John Kennedy

Theses and Dissertations

The measurement of takeoff and landing distance during flight testing of general aviation aircraft requires the accurate measurement of aircraft position over the ground and altitude up to 50 feet above surface elevation. Current methods of evaluating takeoff and landing distances include cinetheodolites, laser and radar trackers, and Differential Global Positioning Systems (DGPS). The use of laser altimetry to range altitude above the ground originated with military and agricultural aircraft. The AgLaser laser module was an infrared laser ranging unit designed for agricultural aircraft to gauge optimal spray height above a field. The AgLaser system has a stated accuracy of …

Assessing The Effects Of Sensitizing Tungsten Oxide With Zinc Telluride, Chengeto Kazuva

Theses and Dissertations

This thesis is a comparison study of the performance of plain tungsten oxide (WO₃) thin films and tungsten oxide thin films sensitized with zinc telluride (ZnTe) as photoelectrocatalysts. Tungsten oxide and zinc telluride are semiconductors which were prepared on indium tin oxide (ITO) coated glass, and subsequently studied for water splitting applications. The main method of synthesis employed was electrochemical deposition. Tungsten oxide thin films were deposited from a precursor solution of peroxotungstic acid while the zinc telluride thin films were deposited from a solution containing dissolved zinc sulfate heptahydrate, sulfuric acid and tellurium dioxide. Surface morphology, film composition and …

Synthesis And Characterization Of 3-D Tissue Engineered Tumor Models For Melanoma Study And Extracellular Matrix Investigation, Joseph L. Spano

Theses and Dissertations

Introduction: Melanoma is the deadliest form of skin cancer, projected to claim over 9,700 American lives and necessitate $3.3 billion in care and treatment costs in 2017. In order to reduce the socioeconomic burdens and lessen cancer-related mortality and morbidity, advancements in early-stage diagnostics and treatments are essential. Two-dimensional (2-D) tissue culture treated plastics (TCTP) are reductionist in vitro models that are commonly used in drug development and preclinical drug evaluation. These models poorly recapture the native tumor microenvironment (TME), providing unrealistic growth conditions, and are thus poorly suited to measure the efficacy of newly emerging therapies. We have developed …

Pegda Pouches To Prevent Adhesions With In Vivo Bioreactor- Based Vascular Graft Strategies, Kranthi Vuppuluri

Theses and Dissertations

Different strategies have been investigated for the fabrication of vascular grafts. Using the peritoneal cavity of the patient as an “in vivo bioreactor” to recruit autologous cells to the implanted vascular conduit is one of the promising options. One of the main drawbacks with this strategy is the potential to form adhesions in the peritoneal cavity. In this project we are trying to address this potential side-effect by using polyethylene (glycol) diacrylate (PEGDA) to produce a hydrogel pouch into which the electrospun conduits are placed, with the goal of reducing the potential to form peritoneal adhesion after implantation. PEG is …

Repeatability Of Reference Signal Received Power Measurements In Lte Networks, Hayder A Abdulrasool Khzaali

Theses and Dissertations

No abstract provided.

Low Complexity Transmission Schemes For Future Wireless Communication Systems, Geamel Alyami

Theses and Dissertations

Future of mobile communication technologies is coupled with multi-antenna systems. Recent research results encourage a massive increase in the number of base station antenna elements in order to meet high data rate demands. However, at the current mobile communication frequencies (< 6 GHz), the amount of spectrum is very limited. Therefore, increase number of antenna elements and higher carrier frequencies in millimeter wavelength range need to be understood and their corresponding potentials need to be identified. Studies proposed in this work aim to identify the degree of orthogonality of millimeter wave massive MIMO channels. For this purpose, various simulation based experiments have been done which are based on the state of the art millimeter channel models. Effect of certain propagation parameters such as the probability of existence of LOS link, number of clusters, inter-antenna elements spacing and number of base station antennas in the array have been investigated. It has been found that probability of LOS link has the highest impact at the multiuser orthogonality of the multiuser channels. In general, millimeter wave massive MIMO channels are found to be low rank. Therefore, in the last part of this work a low complexity user selection algorithm is proposed. Novelty of the work is established by both performance and computational complexity comparison. Computational cost of the proposed algorithm is significantly lower than state of the art user algorithms while the sum rate performance is exactly the same as that of best user selection algorithm

Arabic Speech Recognition Systems, Hamda M. M. Eljagmani

Theses and Dissertations

Arabic automatic speech recognition is one of the difficult topics of current speech recognition research field. Its difficulty lies on rarity of researches related to Arabic speech recognition and the data available to do the experiments. Moreover, to build Arabic speech recognition system with an optimal word error rate (WER), the system has to be completely trained to the individual user. Even though speaker dependent system can effectively achieve this by training it explicitly for this one speaker, it requires a large amount of training data. In addition speaker dependent system requires to be trained to each speaker individually. For …

Hybrid Phonon Polaritons Mimic Te Surface Wave Enhanced Supercoupling, Delroy Dominic Rebello

Theses and Dissertations

The study and excitation of surface plasmon polaritons SPhPs modes in polar dielectrics have attracted the interest of a wide range of research in various fields such as biology, physics and engineering. The excitation of SPhP in optical waveguides is because of TM-component of the incident light. TE-components are usually disbarred because, for TE-polarization component, orthogonal to the TM-polarization components, of the incidence waves, no SPhP mode exists. This thesis presents a novel hybrid TE SPhP mode waveguide in the mid-infrared region. By introducing a thin layer of high index dielectric material on the polar dielectric, where SPhPs are excited, …

Optical Nanoantenna Impedance Matching And Duality And Hybrid Surface Phononic Waveguide, Yuancheng Xu

Theses and Dissertations

This work contributes to critical requirements for optical and infrared nanoantenna and waveguide applications; 1) the impedance of an optical nanoantenna is addressed, and 2) long propagation lengths and high confinement waveguide is designed. Optical nanoantennas have been studied as a means to manipulate nanoscale fields, local field enhancements, radiative rates, and emissive directional control. However, a fundamental function of antennas, the transfer of power between a coupled load and far-field radiation, has seen limited development in optical antennas owing largely to the inherent challenges of extracting impedance parameters from fabricated designs. As the transitional element between radiating fields and …

Dynamics Of Asymmetrical Configurations Of Catamaran Hull Forms, Vaibhav Aribenchi

Theses and Dissertations

It is important to understand asymmetrical catamarans motions since it influences the loads which increases stress on structures while causing discomfort to passengers and crew members. Researchers so far have been mainly focused on motions characteristics of the conventional catamaran hull forms. There is scant literature or research work in the public domain on asymmetrical catamaran hull form, with regards to its seakeeping performance. This thesis undertakes a comparative analysis of the motion characteristics between newly developed alternative catamaran hull forms of different asymmetrical configurations. The asymmetrical catamarans developed from the original NPL round bilge catamaran hull forms have a …

Analysis, A Technique, And Incremental Learning Of Wake-Up-Word Speech Recognition, Ahmad Zuhair S. Hasanain

Theses and Dissertations

Even thought the cutting-edge speaker-independent Automatic Speech Recognition (ASR) systems demand big training data, they barely handle time-varying speaking rates, tolerate various uttering alterations, or are robust to noise. In contrast, our Wake-Up-Word (WUW) technique is tuned to these challenges in the light ASR systems with minimal number of initial training samples. It is crucial that users of ASR systems be capable of rolling out new WUW calls swiftly and modifying ASR vocabulary at any time, such as in the cases of foreign WUW addition and adaptation to phonetic change. We had tested our proposed methodologies in the acoustic WUW-II …

Estimation Of Groundwater Loads Into A Coastal Estuary Using Seawat, Antonio S. Berber Jr.

Theses and Dissertations

The research of regional groundwater flow is of vital importance at the Indian River Lagoon (IRL) due to the potential contribution groundwater flow has on nutrients into the IRL. If too many nutrients are introduced into the IRL, algal blooms could occur and impact the health of IRL system. The IRL is a coastal estuary located on the east coast of Florida. Submarine groundwater seepages (SGD) and groundwater loads into the IRL were numerically estimated by using SEAWAT, a program designed to simulate variable-density groundwater flow coupled with multi-species solute transport. Models were completed at three different study transects that …

An Empirical Examination Of Cognitive Chunking And Information Generation In Freehand Sketches During Design Ideation, Omar Magdy Ibrahim Zaki Mohammed Galil

Theses and Dissertations

This thesis proposes a method to measure information content of freehand sketches during design ideation based on the cognitive chunk formation. The research is broken down into two phases. The first is a protocol study to explore chunk formation in freehand sketches by novice designers while generating solutions for a novel design problem. The second is the identification of entities and functional relations explicitly expressed in the designers’ output. Next, a form neutral (F-ER) representation model is formulated, and information metrics are applied to measure the information content. This work is motivated by the notion that engineering design can be …

Dynamic Anchoring In Soft Regolith For Celestial Exploration, Tom Ebert

Theses and Dissertations

Recent exploration missions to celestial bodies have shown an increasing demand for surface based landers and rovers designed to perform experiments on the ground, rather than relying purely on traditional orbiting observatories. Many of the scientifically interesting locations have proven hazardous and difficult to reach and traverse, driving the need for different methods of locomotion. Some of these locations lie in deep, permanently shadowed craters or in rocky, highly uneven landscapes. Various wheeled, flying, jumping and legged rovers have been proposed, some of which have been implemented with success and problems alike. Even though the Curiosity rover has the largest …

Numerical Investigation Of A Phase-Change Material Based Photovoltaic Panel Temperature Regulation System, Rohit Gulati

Doctoral Dissertations and Master's Theses

As the production of clean electricity has gained importance, photovoltaic (PV) panels have become a widely used technology. But, during operation, PV panels heat up due to the solar insolation and suffer a drop in electrical output. The goal of this investigation is to use phase-change materials (PCM) to passively cool PV panels. The PCM is inside an aluminum container attached to the back surface of the PV panel. Four configurations of the container are investigated. The first configuration is a container with bulk PCM occupying its entire interior volume. The depth of this container is varied. The second configuration …

Implementing Spatial Symmetry In The Tensor Contraction Engine, Kevin Hartline

Honors Capstones

No abstract provided.

A Spreadsheet For Estimating Soil Water Characteristic Curves (Swcc), Ghada Ellithy

Publications

SWCC can be measured in the lab; however, due to the cost, time, and high variability in the results, empirical equations were developed using multiple regression approaches on databases consisting of a large number of measured SWCCs. The spreadsheet presented herein utilizes different methods that use basic soil properties, such as grain size distribution and Atterberg limits, to calculate the input parameters for van Genuchten and Fredlund and Xing equations. These parameters are required by numerical models, such as SEEP/W, to perform transient seepage analysis. The spreadsheet allows copying the generated curve data points as well as an input into …

Design Optimization Of A High Power Led Matrix Luminaire, Jose Luiz F. Barbosa, Daniel J. Simon, Wesley P. Calixto

Electrical and Computer Engineering Faculty Publications

This work presents a methodology for optimizing the layout and geometry of an m x n high power (HP) light emitting diode (LED) luminaire. Two simulators are used to analyze an LED luminaire model. The first simulator uses the finite element method (FEM) to analyze the thermal dissipation, and the second simulator uses the ray tracing method for lighting analysis. The thermal and lighting analysis of the luminaire model is validated with an error of less than 10%. The goal of the optimization process is to find a solution that satisfies both thermal dissipation and light efficiency. The optimization goal …

Multipath Channel Considerations In Aeronautical Telemetry, Edem Coffie Gagakuma

Theses and Dissertations

This thesis describes the use of scattering functions to characterize time-varying multipath radio channels. Channel Impulse responses were measured at Edwards Air Force Base (EAFB) and scattering functions generated from the impulse response data. From the scattering functions we compute the corresponding Doppler power spectrum and multipath intensity profile. These functions completely characterize the signal delay and the time varying nature of the channel in question and are used by systems engineers to design reliable communications links. We observe from our results that flight paths with ample reflectors exhibit significant multipath events. We also examine the bit error rate (BER) …

Design Of Logan City's Stormwater Conveyance System, Kade Jacob Beck

Undergraduate Honors Capstone Projects

This report summarizes 10th West Engineers' (10WE) storm water conveyance design for Logan City. The implementation of the design mitigates flood risk due to storm water discharge , helps improve local water quality, and uses infrastructure that would otherwise be abandoned. The system collects storm water discharged along 1000 West and transports the water to the holding pond located at approximately 2400 West 2200 North, Logan, Utah (see Figure 1).

Figure 1. Aerial Photo of the Area of Interest Current Conditions

Logan City is located in northern Utah's Cache County. As development and redevelopment occur, storm water runoff quantities will …

Reference Evapotranspiration From Coarse-Scale And Dynamically Downscaled Data In Complex Terrain: Sensitivity To Interpolation And Resolution, Courtenay Strong, Krishna B. Khatri, Adam K. Kochanski, Clayton S. Lewis, L. Niel Allen

Civil and Environmental Engineering Faculty Publications

The main objective of this study was to investigate whether dynamically downscaled high resolution (4-km) climate data from the Weather Research and Forecasting (WRF) model provide physically meaningful additional information for reference evapotranspiration (E) calculation compared to the recently published GridET framework that uses interpolation from coarser-scale simulations run at 32-km resolution. The analysis focuses on complex terrain of Utah in the western United States for years 1985–2010, and comparisons were made statewide with supplemental analyses specifically for regions with irrigated agriculture. E was calculated using the standardized equation and procedures proposed by the American Society of Civil Engineers from …

Casimir And Van Der Waals Effects On Electrostatically Actuated Nems Resonator Sensors, Christian Reyes

Theses and Dissertations

The behavior of nano and micro-electromechanical systems (N/MEMS) cantilever beams under electrostatic actuation is studied. The cantilever system is actuated by soft AC voltage that is set to a frequency of near half natural and near natural frequency of the beam. These actuating frequencies result in primary and parametric resonances, respectively. Two methods are used to analytically model the behavior of the cantilever. The first method is Method of Multiple Scales (MMS), which is a perturbation method that works for small parameters. The second method is the Reduced Order Method (ROM), which is a Galerkin method that works for large …