Engineering Commons^™

The Effects Of Sensor Performance As Modeled By Signal Detection Theory On The Performance Of Reinforcement Learning In A Target Acquisition Task, Nate Quirion

Doctoral Dissertations and Master's Theses

Unmanned Aerial Systems (UASs) today are fulfilling more roles than ever before. There is a general push to have these systems feature more advanced autonomous capabilities in the near future. To achieve autonomous behavior requires some unique approaches to control and decision making. More advanced versions of these approaches are able to adapt their own behavior and examine their past experiences to increase their future mission performance. To achieve adaptive behavior and decision making capabilities this study used Reinforcement Learning algorithms. In this research the effects of sensor performance, as modeled through Signal Detection Theory (SDT), on the ability of …

The Effect Of Microencapsulated Phase-Change Material On The Compressive Strength Of Structural Concrete, Chad Norvell, David J. Sailor, Peter Dusicka

Mechanical and Materials Engineering Faculty Publications and Presentations

Latent heat energy storage through phase-change materials (PCMs) is one possible strategy to control interior temperatures in buildings, improve thermal comfort, and passively reduce building energy use associated with heating and cooling. While PCMs integrated into building structure elements have been studied since the 1970s, challenges of integrating PCMs into building materials while maintaining their heat storage benefits have limited their application in practice. The recent introduction of microencapsulated phase-change materials provides the energy storage capability of PCMs in micron-scale, chemically-inert capsules that can be easily integrated into composite materials such as gypsum wallboard and concrete. The size and physical …

Surgical Tooling Designed For The Direct Anterior Approach To Total Hip Arthroplasty, Jon-Peter Meckel

Master's Theses

Surgical Tooling Designed for the Direct Anterior Approach to Total Hip Arthroplasty Jon-Peter Meckel

Total hip arthroplasty (THA) is becoming more and more common in the US as people continue to live longer and more active lives. The main reason that a THA is required is due to the “wear and tear” affliction of osteoarthritis, which in the year 2000 had at least 3% of the population over 30 showing symptoms. A revitalized approach to THA is the direct anterior approach, or Smith-Petersen approach, which limits the amount of musculature affected by the surgery and creates a very stable joint …

Microphone-Based Pressure Diagnostics For Boundary Layer Transition, Spencer Everett Lillywhite

Master's Theses

An experimental investigation of the use low-cost microphones for unsteady total pressure measurement to detect transition from laminar to turbulent boundary layer flow has been conducted. Two small electret condenser microphones, the Knowles FG-23629 and the FG-23742, were used to measure the pressure fluctuations and considered for possible integration with an autonomous boundary layer measurement system. Procedures to determine the microphones’ maximum sound pressure levels and frequency response using an acoustic source provided by a speaker and a reference microphone. These studies showed that both microphones possess a very flat frequency response and that the max SPL of the FG-23629 …

Robust And Resilient Finite-Time Bounded Control Of Discrete-Time Uncertain Nonlinear Systems, Mohammad N. Elbsat, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Finite-time state-feedback stabilization is addressed for a class of discrete-time nonlinear systems with conic-type nonlinearities, bounded feedback control gain perturbations, and additive disturbances. First, conditions for the existence of a robust and resilient linear state-feedback controller for this class of systems are derived. Then, using linear matrix inequality techniques, a solution for the controller gain and the maximum allowable bound on the gain perturbation is obtained. The developed controller is robust for all unknown nonlinearities lying in a known hypersphere with an uncertain center and all admissible disturbances. Moreover, it is resilient against any bounded perturbations that may alter the …

Dual-Carrier High-Gain Low-Noise Superlattice Avalanche Photodiodes, Jun Huang, Koushik Banerjee, Siddhartha Ghosh, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

In this paper, novel avalanche photodiode structures with alternate carrier multiplication nanometer regions, placed next to a wider electron multiplication region, to create dual-carrier feedback systems, are proposed. Gain and excess noise factor of these structures are calculated based on the dead space multiplication theory under uniform electric field. In addition, the equivalent impact ionization ratios are derived and compared. It is observed that the proposed structures can generate much higher gain compared with conventional pure electron multiplication structures under the same electric field without severely degrading the excess noise quality. Excess noise is further optimized with careful adjustment of …

Fabrication And Modeling Of Electrochemical Double-Layer Capacitors Using Carbon Nano-Onion Electrode Structures, Fabio Parigi

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Electrochemical capacitors or ultracapacitors (UCs) that are commercially available today overcome battery limitations in terms of charging time (from tens of minutes to seconds) and limited lifetime (from a few thousand cycles up to more than one million) but still lack specific energy and energy density (2-5% of a lithium ion battery). The latest innovations in carbon nanomaterials, such as carbon nanotubes as an active electrode material for UCs, can provide up to five times as much energy and deliver up to seven times more power than today’s activated carbon electrodes. Further improvements in UC power density have been achieved …

Driver Fatigue Enforcement Techniques And Their Effect On Crashes, Carrie Mohlman

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Fatigued driving is a type of driver impairment caused by a lack of sleep, sleep disorders, long drive times, etc. Fatigued driving enforcement aims to improve safety by removing impaired drivers from the roadway. While fatigued driving is detrimental to safety, there exists the issue of identifying fatigue. There is a range between being awake and asleep and, in order to improve safety, enforcement officers must be able to identify the point at which drivers are impaired.

This thesis investigates potentially effective fatigued driving enforcement techniques for use by enforcement officers. These techniques were investigated through three primary means: a …

Assessing The Impact Of Speed Limit Reduction Near Signalized High Speed Intersections Equipped With Advance Warning Flashers: A Case Study In Nebraska, Shefang Wang

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis evaluated the effects of 5 mph and 10 mph speed limit reductions in the vicinity of high-speed, signalized intersections equipped with Advance Warning Flashers (AWF). The selected methodology involved a field study of the impact of speed limit reduction at 7 high-speed, signalized intersections with AWF, using quantile regression models developed for speed. The quantile regression models for speed indicated that reduction of the speed limit from 60 mph to 55 mph did not have significant impact on observed speed during the green time. However, it was found that speed limit reduction from 65 mph to 55 mph …

Structural Reliability Analysis Of Corroded Steel Girder Bridge, Mohammed Shaalan Al Badran

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The natural aging, environmental impact, and appropriate design are certainly playing a serious role in safety of the bridges function. The functional safety of bridge constitutes a prime element of the transportation system serving commuters, passengers and freight. According to Federal Highway Administration, the steel bridges share represents a large amount of the United States’ bridges. In last century, the collapse of both the Silver Bridge at Point Pleasant, West Virginia over the Ohio River on December 15, 1967 and over the Mianus River Bridge in Connecticut on June 28, 1983 showed that steel corrosion has been the leading reason …

Velocity Measurements Of The Flow Over A Gate-Controlled Weir Structure, Mohamed M. Jalloh

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The South Florida Water Management District (SFWMD) uses G304 control structures to manage flow into and out of a large storm-water treatment area (STA). These structures consist of a lateral unsuppressed weir, a sluice gate and a corrugated culvert for flow control and transfer through an embankment. For better flow control in the STAs, it is imperative to accurately measure the discharge through the G304 control structures and to determine the approach velocity over the weir for different field scenarios.

Flow behavior of the G304 structure was examined in a prototype during two days of testing for two canal headwater …

Real-Life Vehicle Routing With Non-Standard Constraints, Wee Leong Lee

Research Collection School Of Computing and Information Systems

Real-life vehicle routing problems comprise of a number of complexities that are not considered by the classical models found in vehicle routing literature. I present, in this paper, a two-stage sweep-based heuristic to find good solutions to a real-life Vehicle Routing Problem (VRP). The problem I shall consider, will deal with some non-standard constraints beyond those normally associated with the classical VRP. Other than considering the capacity constraints for vehicles and the time windows for deliveries, I shall introduce four additional non-standard constraints: merging of customer orders, controlling the maximum number of drop points, matching orders to vehicle types, and …

Parameters Optimization Of Copper Wire Bonding On Thin Small Outline Package, S Srikamonsirisak, U Tantinuchawong, Y Satirakul

Journal of Metals, Materials and Minerals

With significant rising of Au price, there is growing demand to implement Cu wire bonding as an alternative method for Au wire bonding. However, there are several challenges to overcome because Cu is easily oxidized and its property is harder than Au. The oxidation deteriorates bondability and bond reliability, while the greater wire hardness leads to the more severe wire bonding parameters (higher force, higher power, higher temperature), which results in physical damage of the bond pad and underlying layers. This paper reveals wire bonding parameters optimization in order to implement Cu wire bonding in high volume production environment with …

Application Of Para Rubber Latex Mixed With Organic Dyes As Printing Ink For Biodegradable Plastic Film, T Techochaingam, S Netpradit, K Tanprasert, P Boochathum

Journal of Metals, Materials and Minerals

content of 35.9% and 41.2%, which had the viscosity of 9.52 seconds and drying time of around 5 minutes. The viscosity of Para rubber latex with solid content of 59.0% and 61.4% was very high; thus, resulted in coagulation. Then modified rubber latex CNR with solid content of 16.5%, 19.2%, 26.8% and 28.2%, which had the viscosity around 8.30 seconds and drying time of around 5 minutes. Dye solution was prepared by adding 1 part of dye to 1 part of water (w/w). The formulation of ink that yielded the highest optical density of 1.43 was 8.4 g dye solution …

Conversion Of Secondary Pulp And Paper Sludge To Glucose By Hydrothermal Treatment, N Chariyaprasertsin, Y Matsumura, T Charinpanitkul

Journal of Metals, Materials and Minerals

Secondary pulp/paper sludge is residue from water treatment process of the paper industry. Main components of secondary pulp/paper sludge are cellulose, hemicelluose, lignin and calcium carbonate (CaCO3). The cellulose and hemicellulose could be converted to glucose by hydrothermal treatment in a stainless steel tubular batch reactor. It was found that dried powder of secondary pulp/paper sludge with nominal size in a range of 595 to 840 m contains different content of CaCO3. Therefore, effect of CaCO3 content on glucose yields was examined under designated temperature of 200-260 C and treating time of 0-40 minutes. Identification and quantification of glucose and …

Characterization Of Diamond-Like Carbon (Dlc) Films Deposited By Filtered Cathodic Vacuum Arc Technique, N Konkhunthot, C Euaruksakul, P Photongkam, P Wongpanya

Journal of Metals, Materials and Minerals

Diamond-like carbon (DLC) films were prepared on AISI H13 hot-work tool steel substrates by filtered cathodic vacuum arc (FCVA) technique under variable substrate DC biasing. The atomic structures of the films were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy, and near edge x-ray absorption fine structure spectroscopy. The Raman spectra revealed that when the magnitude of the bias voltage increased, the G peak was shifted toward lower wave numbers, and indicated that the sp3 content in the DLC films increased. The ratios between the sp3 and sp2 bonds in the films were verified by X-ray photoelectron spectroscopy, and the analyses …

Kinetics Of Tomato Peroxidase Inactivation By Atmospheric Pressure Cold Plasma Based On Dielectric Barrier Discharge, Patrick J. Cullen, Shashi Pankaj, N. Misra

Articles

Atmospheric pressure cold plasma technology is an emerging nonthermal food technology for microbiological decontamination of food and bio-materials. This study demonstrates the applicability of in-package cold plasma technology as a novel means to inactivation of enzymes. The kinetics of inactivation of tomato peroxidase as a model enzyme was studied at 30, 40 and 50kV, for up to 5’ of atmospheric air dielectric barrier discharge plasma treatments. The enzyme activity was found to decrease with both treatment time and voltage, the former variable exhibiting a more pronounced effect. Kinetic models viz. first-order, Weibull and logistic models were fitted to the experimentally …

Advanced Circularly Polarised Microstrip Patch Antennas, Adam Z. Narbudowicz

Doctoral

The thesis describes outcomes of research on advanced circularly polarised antennas. The proposed designs are intended for integration into small mobile devices, therefore low profile and easy manufacturability are key parameters, along with good CP radiation properties. The designs were validated by simulation and measurement, and are also backed by theory and design guidelines. The primary focus is on the development of planar omnidirectional circularly polarised antennas, which are fabricated using multilayer PCB techniques and thus are lightweight and cost-efficient. Unlike in classical microstrip patch antenna designs, the groundplane of the proposed antenna was substantially reduced. This helps to achieve …

Adaptive Ofdm For Wireless Interconnect In Confined Enclosures, Vit Sipal, Javier Gelabert, Christopher J. Stevens, Ben Allen, David Edwards

Articles

This letter considers and recommends OFDM with adaptive subcarrier modulation as a suitable candidate for wireless UWB communication in computer chassis. A rigorous measurement campaign studies the guaranteed spectral efficiency. It concludes that enhancement of the existing WiMedia OFDM systems with a bandwidth of 528 MHz in order to support adaptive OFDM would enable data-rates above 1 Gbps over short ranges, i.e. the spectral efficiency would be doubled. Moreover, the guaranteed spectral efficiency is shown to increase with bandwidth, i.e. the guaranteed data-rate increases better than linearly with bandwidth.

Multi-Objective Preliminary Design Optimization Of Planing Craft Using Differential Evolution And Artificial Networks, Robert Eugene Weidman

Mechanical & Aerospace Engineering Theses & Dissertations

The differential evolution (DE) algorithm is an evolutionary algorithm that has been utilized as a metaheuristic optimizer in the last few years. A recently developed multi-objective version of DE is utilized in this research in order to optimize the preliminary design of planing craft. The craft performance is evaluated using the planing hull preliminary design software PHAST. The optimization problem objectives are the craft acquisition cost and the overall measure of effectiveness; the latter comprises various performance aspects: ride quality, transportability, payload, and mobility. Static stability and operating constraints are also considered. Each of the aforementioned four measures of effectiveness …

Halogenated Sorbitol Derivatives Using As Nucleating Agent And Their Effect On Orientation Of Polypropylene Fiber, T Sutthatang, S Wangsoub

Journal of Metals, Materials and Minerals

In this work, two halogenated derivatives of benzylidene sorbitol were synthesized by reacting D-sorbitol with an aromatic aldehyde in the present of an acid catalyst. ie.chloro and bromo derivatives for using as nucleating agent for polypropylene. For chloro derivative, different positions of substituent (ortho, meta and para) were also synthesised. SEM and TEM micrographs of gel extracted from organic solvent revealed long fibril network of chloro and bromo substitutes which their diameters are in the range of about 10-200 nm. Small amount (0.1-1%wt) of these materials was blended with isotactic polypropylene (iPP) by two roll mill machine and the mixture …

Upconversion Luminescence Of Yttrium Oxysulfide Co-Doped With Rare Earth Elements, U Injarean, P Pichestapong, T Ruangsiritanyakul, S Tayaniphant

Journal of Metals, Materials and Minerals

Rare earth ions doped upconversion phosphors have been used in many applications such as infrared laser detecting, anti-counterfeit protection and solid state display. In this study, yttrium oxysulfide (Y2O2S) compounds co-doped with rare earth elements, ytterbium (Yb), and one of the following elements, erbium (Er), thulium (Tm), europium (Eu) or holmium (Ho) were synthesized from doped rare earth oxides using sulfide fusion method with pelletization pretreatment. The doping was carried out with the mixing of yttrium nitrate and rare earth nitrate solutions to obtain homogeneous mixture. The mixed nitrate solution was precipitated with oxalic acid and calcined to doped oxide …

Titanium Dioxide Nanostructures Synthesized By Sonochemical Hydrothermal Process, N Wongpisutpaisan, C Kahattha, N Vittayakorn, A Ruangphanit, W Pecharapa

Journal of Metals, Materials and Minerals

Titanium dioxide particles were prepared by sonochemicalhydrothermal process from a precursor of titanium isopropoxide in the presence of polyvinyl alcohol aqueous solution. Sonication of the precursor was conducted using sonic horn operated at 20 kHz until the completely precipitated product was reached. As-obtained intermediate products were then loaded into a Teflon-lined stainless steel autoclave for hydrothermal process with10M NaOH aqueous solution and heated under different temperature 80-120C. The synthesized products were characterized of structural properties and surface morphology by X-ray diffraction spectroscopy and field emission scanning electron microscope. The results show that prepared samples have a good crystallinity and the …

Crystallization Behavior Of Pla In Pla/Nr Compared With Dynamic Vulcanized Pla/Nr, C Thongpin, S Klatsuwan, P Borkchaiyapoom, S Thongkamwong

Journal of Metals, Materials and Minerals

PLA has been an interesting biopolymer widely used in various applications. It has been widely known that crystallization of PLA is rather slow. After melt processing, crystallinity of PLA could be lost. The study of PLA added with fibers, particles or even nano-particles has been studied extensively. Nonetheless, the suffering in some mechanical characteristic such as toughness has been encountered. Our research was aimed to enhance toughness of PLA by melt blending NR, and dynamic vulcanized NR into PLA using an internal mixer. PLA:NR and PLA:NR vulcanizate with the ratio of 90:10, 80:20, 70:30, 60:40 and 50:50 were studied. Crystallization …

Dissolved Oxygen Sensor Film Using Ruthenium Polypyridine Complex As Luminophore, C Su-Ngam, Sh Thang, A Wongchaisuwat, L Meesuk

Journal of Metals, Materials and Minerals

Ruthenium polypyridine complex was synthesized by using RAFT process. The Ruthenium was immobilized in 2 silicone matrices, polydimethylsiloxane(PDMS) and KE 200 (silicone elastomer base)/CX200 (curing agent). KE 200/CX200 is the alcohols curing type silicone. Both sensor films showed absorption peak at 460 nm and luminescence peak at 610 nm. The KE200/CX200 film gave linear response to dissolved oxygen up to 80% O2 (18 ppm) follow Stern-Volmer equation with R2 of 0.990. The measured luminescence intensity decreased with increasing dissolved oxygen water temperature from 25 to 70c. After being irradiated with 460 nm light source for 3 hrs, the sensor film …

Low Temperature Chemical Precipitation And Characterization Of Ceria Based Ceramic Composite Oxide Materials, D Radhika, A Samson Nesaraj

Journal of Metals, Materials and Minerals

Ceria based ceramic composite oxide materials such as Ce0.9Gd0.1O2-δ -Ce0.9Y0.1O2-δ and Ce0.8Gd0.2O2-δCe0.8Y0.2O2-δ were prepared by a simple chemical precipitation method for application in low temperature solid oxide fuel cells (LTSOFCs) as electrolytes. The precursor materials used in this synthesis were cerium nitrate hexahydrate, gadolinium nitrate and yttrium nitrate (as basic materials), sodium hydroxide (as precipitator material) and PVA (as surfactant). A mixture of metal hydroxides was formed when the aqueous mixture of basic materials mixed with the aqueous precipitant solution in proper stoichiometric composition. The resultant hydroxide mixture was washed with ethanol and water mixture (1:9 volume ratio) to remove …

Macrostructure Modeling Of Al-20 % Sn Alloy, P Padhi, Ak Sahoo, S Kar

Journal of Metals, Materials and Minerals

In metallic alloys, the formation of macrostructure involves different length and time scales. The macrostructure strongly influences the mechanical properties of the materials. Modeling of macrostructure provides valuable insights for tailoring of the structure. In the present study simulation of macrostructure in Al-20Sn has been carried out. Expression for nucleation rate and growth rate were tuned to get a match with the experimentally observed macrostructure. The study incorporates the motion of grains due to Brownian motion. Incorporation of Brownian motion resulted in more uniform distribution locally, which has been experimentally observed. Both simulation and macrograph showed few columnar grains and …

Why A 15 Minute Biological Detection System?, Doug Lewis

Faculty Publications

The biological defense community needs to take a hard look at the requirements and assumptions we use to develop our biological sensors. Today the point sensors currently deployed or in development can offer at best “near real time” detection. This translates into approximately 10-20 minutes from the time an agent passes over the device until an alarm is issued. Why are we working to develop detection hardware which in reality contributes little to no advantage to an operational environment? Should the DOD resist fielding (in the near term) “near real time” detection systems, and instead field slower (but much more …

Current Barriers To Successful Implementation Of Fist Principles, Brandon Keller, Joseph R. Wirthlin

Faculty Publications

The Fast, Inexpensive, Simple, and Tiny (FIST) framework proposes a broad set of organizational values, but provides limited guidance on practical implementation. Implementing FIST principles requires clarifying the definitions of “fast,” “inexpensive,” and “simple,” recognizing where FIST does and does not apply. Additionally, a subset of the FIST heuristics was expanded upon to increase their usefulness for practitioners. The primary research findings are that FIST principles are less conducive for highly complex or novel systems, immature technologies, future needs, acquisitions in early development phases, or when performance is the foremost value. FIST principles were also found to be constrained by …

Tesla: An Extended Study Of An Energy-Saving Agent That Leverages Schedule Flexibility, Jun Young Kwak, Pradeep Varakantham, Rajiv Maheswaran, Milind Tambe, Burcin Becerik-Gerber

Research Collection School Of Computing and Information Systems

This paper presents transformative energy-saving schedule-leveraging agent (TESLA), an agent for optimizing energy usage in commercial buildings. TESLA’s key insight is that adding flexibility to event/meeting schedules can lead to significant energy savings. This paper provides four key contributions: (i) online scheduling algorithms, which are at the heart of TESLA, to solve a stochastic mixed integer linear program for energy-efficient scheduling of incrementally/dynamically arriving meetings and events; (ii) an algorithm to effectively identify key meetings that lead to significant energy savings by adjusting their flexibility; (iii) an extensive analysis on energy savings achieved by TESLA; and (iv) surveys of real …