Digital Commons Network^™

Use Of Environmental Isotope Tracer And Gis Techniques To Estimate Basin Recharge, Abdulganiu A.A. Odunmbaku

Open Access Theses & Dissertations

The extensive use of ground water only began with the advances in pumping technology at the early portion of 20th Century. Groundwater provides the majority of fresh water supply for municipal, agricultural and industrial uses, primarily because of little to no treatment it requires. Estimating the volume of groundwater available in a basin is a daunting task, and no accurate measurements can be made. Usually water budgets and simulation models are primarily used to estimate the volume of water in a basin.

Precipitation, land surface cover and subsurface geology are factors that affect recharge; these factors affect percolation which invariably …

Identification Of Rework Station Location To Enhance Reworkability Using Design For Disassembly, Juan Alejandro Saavedra

Open Access Theses & Dissertations

Rework stations are commonly established as part of each assembly stations causing the material flow of the process to be constantly interrupted. Another option is to place the rework station at the end of the production, but this is not cost effective. This breakeven point between reworkability and cost methodology has been proposed in this thesis to identify the location of a single rework station in an assembly line in order to enhance reworkability using the Design for Disassembly (DfD) principles. The methodology uses the 17 guidelines of DfD in a manufacturing scenario in order to propose a reworkability index …

Investigation On A Gas-Solid Fluidized Bed Hydrodynamics Using A Non-Intrusive Technology To Visualize Flow Field, Md Rashedul Hasan Sarker

Open Access Theses & Dissertations

The biggest challenge for 21st century is to fulfill global energy demand and at the same time reduce detrimental impact on environment. Gasification technology can meet the requirement and also reduce emission without compromising its performance. In coal gasification, instead of burning coal completely a partial combustion takes place with presence of steam and limited amount of oxygen. In this controlled environment a chemical reaction takes place and produces a mixture of clean synthetic gas. Gas-solid fluidized bed is one type of gasification technology. During gasification mixing behavior of solid (coal) and gas and their flow pattern very complicated to …

Graphene Stuctures For Energy Storage Application, Mohammad Arif Ishtiaque Shuvo

Open Access Theses & Dissertations

Energy storage devices are receiving extensive attention in recent years due to the increasing demand of energy. Super-capacitor is one of the energy storage devices with high specific power density and wide applications in electronic vehicles, commercial mobile electronics, and military devices. Carbon based materials are widely used in making Electrochemical Double Layer Capacitor (EDLC) or super-capacitor for their excellent porous nature along with their electron transport capability. By increasing the specific surface area of the porous carbon materials, specific capacitance of the super-capacitor can be significantly improved. Graphene, a newly discovered material, has been incorporated in making super-capacitor electrodes …

A Database For Estimating Organ Dose For Chest And Head Ct Scans For Arbitrary Spectra And Angular Tube Current Modulation, Franco Rupcich, Andreu Badal, Iacovos Kyprianou, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose: The purpose of this study was to develop a database for estimating organ dose in a voxelized patient model for coronary angiography and brain perfusion CT acquisitions with any spectra and angular tube current modulation setting. The database enables organ dose estimation for existing and novel acquisition techniques without requiring Monte Carlo simulations. Methods: The study simulated transport of monoenergetic photons between 5 and 150 keV for 1000 projections over 360◦ through anthropomorphic voxelized female chest and head (0◦ and 30◦ tilt) phantoms and standard head and body CTDI dosimetry cylinders. The simulations resulted in tables of normalized dose …

Bod5 And Cod Data Analysis From The Northwest And Robert R. Bustamante Wastewater Treatment, Juan Carlos Adame

Open Access Theses & Dissertations

The objectives of this thesis are to explore the use of basic Statistical Process Control in a Wastewater Treatment Plant with secondary treatment. Additionally, to describe statistical behavior and review normality of some reportable parameters, also to analyze mainly parameters like BOD5 (Biological Oxygen Demand), Electrical Conductivity, and COD (Chemical Oxygen Demand) with seasons of the year and days of the week, using data from the Northwest (NW) and Robert R. Bustamante (RRB) Wastewater Treatment Plants from El Paso Texas.

The scope of this analysis is to understand how Statistical Process Control can help to predict peak and valleys of …

Sustainable Riparian Restoration - The Utilization Of Sewage Effluent To Construct Wetlands Along The Rio Grande: A String Of Pearls Approach To Replenishment, Michael Earl Landis

Open Access Theses & Dissertations

The Rio Grande, from Elephant Butte Dam to El Paso, has been transformed from a free-flowing wild river into a highly engineered irrigation system. The Rio Grande Project, authorized by Congress in 1905, mandated the Bureau of Reclamation to store and deliver water exclusively to farmers. The river, maintained by the International Boundary and Water Commission, has been straightened and channelized between levees. The laws and policies governing the use of the waters of the Rio Grande are prohibitive to ecological restoration. Prior Appropriation doctrine allows for the exclusive use of these waters.

One sustainable tactic for replenishing the denuded …

Microscopic And Spectroscopic Analysis Of Wo3 And Ti-Doped Wo3 Thin Films, Young Taek Yun

Open Access Theses & Dissertations

Tungsten oxide (WO3) has been a subject of high interest for its unique properties, and recently for its importance in different types of industrial applications which ranges from non-emissive displays, optical, microelectronic, catalytic/photocatalytic, humidity, temperature, gas, and biosensor devices. In this study, WO3 and Ti doped thin films were prepared using radio frequency magnetron reactive sputtering at different substrate temperatures ranging from room temperature to 500 ºC in increments of 100 ºC. After forming a hypothesis based on knowledge of established WO3 properties, we attempt in this work to investigate how the doping influences the roughness and the mean grain …

Designing Optimal Aviation Baggage Screening Strategies Using The Monkey Search Algorithm, Edgar Ivan Jimenez

Open Access Theses & Dissertations

This thesis addresses the aviation baggage screening design problem considering several baggage screening devices which may be used for system implementation, the devices have different false clear and false alarm rates, throughput and purchase costs. In the present research, a comprehensive cost function which not only includes the cost associated with purchase and operation of baggage security devices, but also includes the indirect costs associated with device errors is used. A new monkey search based evolutionary algorithm is presented to determine the best selection of baggage screening security devices in order to minimize the expected annual total cost. The final …

Magnetic Cell Separation By Inkjet Printing For Disease Monitoring, Sylvia Lucia Natividad

Open Access Theses & Dissertations

The standard analysis technique for cell sorting, flow cytometry, requires centralized facilities such as tertiary Medical Centers. According to the U.S. Department of Health and Human Services Designated Health Professional Shortage Areas (HPSA) Statistics, in this country alone, more than 35 million people live in medically underserved areas, many of which need access to diagnostic procedures for proper management of their diseases. A cell sorting technique that can be done in low-resource settings at a decreased cost to the medical organization and the patient has been developed through this research project. By combining inkjet printing technology and magnetic labeling of …

Decision Rule Induction For Service Sector Using Data Mining- A Rough Set Theory Approach, Zhonghua Hu

Open Access Theses & Dissertations

Nowadays, data mining is more widely used than ever before; not only by the academic area, but also in the industry and business area. Apart from execution of business processes, the creation of knowledge base and its utilization for the benefit of the organization is becoming a strategy tool to compete. Despite of having ever growing data bases, the problem is that the finance company fails to fully capitalize the true benefits which can be gained from this great wealth of information. The data mining technology instead of classic statistical analysis is developed to help the people to discover the …

Multi-Objective System Design Optimization Considering Environmental Emissions, Olivia Carolina Moreno

Open Access Theses & Dissertations

The well-known reliability optimization problem, the redundancy allocation problem (RAP) involves the simultaneous selection of system components and a design level configuration that can meet several design constraints in order to optimize the predefined objective function(s). The RAP has been predominantly solved as a single objective optimization problem with the reliability of the system to be maximized or system design cost to be minimized. When considered as a multiple objective reliability optimization problem, the system reliability is maximized and the cost and weight of the system are minimized. In this work, the RAP was formulated as a multiple objective optimization …

The Influence Of Build Parameters On The Microstructure During Electron Beam Melting Of Ti6al4v, Karina Puebla

Open Access Theses & Dissertations

With the demand of devices to replace or improve areas, such as: electronic, biomedical and aerospace industries. Improvements in these areas of engineering have been in need due to the customer’s needs for product properties requirements. The design of components must exhibit better material properties (mechanical or biocompatible) close to those of any given product. Rapid prototyping (RP) technologies that were originally designed to build prototypes may now be required to build functional end-use products. To carry out the transition, from RP to rapid manufacturing (RM), the available materials utilized in RP must provide the performance required for RM. The …

Low Energy Disruption Of Lipid Containing Biomass, Joaquin Rodriguez

Open Access Theses & Dissertations

Lipid containing biomass from microalgae has received recent research interest as a renewable and sustainable feedstock for biofuel production. Algae is known to offer as much as 30 times the energy density than corn based ethanol, the current world standard for biomass based liquid transportation fuels. The development of large scale systems and methods of extracting lipids from microalgae is still in the early stages of development and significant increases in efficiency and reduction in costs are necessary to substantiate algae as a feasible alternative source of fuel. Traditional conversion of algae feedstock into a refineable feedstock for biofuel can …

A Study Of International Wastewater Challenges And Policy In The Tijuana River Watershed, Gloria Ann Villaverde

Open Access Theses & Dissertations

Since the 1930s, untreated and undertreated sewage from Tijuana, Baja California, México has been released into the Tijuana River Watershed causing contamination of the water supply, crops, the Tijuana Estuary and California beaches. Passage of the North American Free Trade Agreement (NAFTA) has exacerbated the problem by causing population and industrial growth explosions for which there have been insufficient services to meet the needs of the people. The waters of the Tijuana River flow (from México) north over the International Border, into the Tijuana Estuary, discharge out to the Pacific Ocean and often flow north, up the California Coast; therefore, …

Implementation Of Evolutionary Algorithms On The Power Industry And Aviation Security, Anuar Jesus Aguirre

Open Access Theses & Dissertations

The main objective of the power electric power grid is to supply reliable electricity to all the customers. Customers could be industrial, commercial, household, transportation and others. The power grid is a complex and large, and it formed by the conjunction of the generation, transmission and distribution system. The present research is focused in power distribution system. A new component replacement analysis method to solve component replacement problems for complex electricity distribution systems using Genetic Algorithms is developed. In the present model a Taylor series expansion is used to approximate the associated opportunity cost for each component in the system. …

The Application Of Fuzzy Granular Computing For The Analysis Of Human Dynamic Behavior In 3d Space, Murad Mohammad Alaqtash

Open Access Theses & Dissertations

Human dynamic behavior in space is very complex in that it involves many physical, perceptual and motor aspects. It is tied together at a sensory level by linkages between vestibular, visual and somatosensory information that develop through experience of inertial and gravitational reaction forces. Coordinated movement emerges from the interplay among descending output from the central nervous system, sensory input from the body and environment, muscle dynamics, and the emergent dynamics of the whole neuromusculoskeletal system.

There have been many attempts to directly capture the activities of the neuronal system in human locomotion without the ability to clarify how the …

Three-Dimensional Structural Electronic Integration For Small Satellite Fabrication, Cassie Gutierrez

Open Access Theses & Dissertations

The ability to realize truly three-dimensional electronic circuits is complicated if not impossible using traditional fabrication techniques. Such techniques are limited to the use of two dimensional printed circuit boards (PCBs), and require various dissonant processes which exhaust time, volume and cost. Due to the nature of Additive Manufacturing (AM) such problems are diminished and in some ways completely overcome. Additive Manufacturing allows for a higher range of design freedom along conformal surfaces, as well as unit level customization; it is the threshold for embedded electronics, allowing for three-dimensional circuitry in ways traditional fabrication is unfeasible. In such ways, additive …

Optimizing Reservoir-Stream-Aquifer Interactions For Conjunctive Use And Hydropower Production, Hala Fayad, Richard C. Peralta, Ali Forghani

Civil and Environmental Engineering Faculty Publications

Conjunctive management of water resources involves coordinating use of surface water and groundwater resources. Very few simulation/optimization (S-O) models for stream-aquifer system management have included detailed interactions between groundwater, streams, and reservoir storage. This paper presents an S-O model doing that via artificial neural network simulators and genetic algorithm optimizer for multiobjective conjunctive water use problems. The model simultaneously addresses all significant flows including reservoir-stream-diversion-aquifer interactions in a more detailed manner than previous models. The model simultaneously maximizes total water provided and hydropower production. A penalty function implicitly poses constraints on state variables. The model effectively finds feasible optimal solutions …

Zno Nanostructures: Growth, Characterization And Applications, Mikhail Ladanov

USF Tampa Graduate Theses and Dissertations

ZnO nanostructures have been investigated for quite a long time. However, only recently they triggered much interest due to advances in materials synthesis and characterization, as well as emerging demand for new nanostructured materials in novel device implementations.

A large part of the work was devoted to exploring new methodology for patterning growth sites and controlling nanowires morphology using the deposition methods that are compatible with integrated circuits (IC) processing. Microcontact printing was used to pattern the seeding layer, and, subsequently, ZnO nanowires through a resistless soft lithography process.

When considering hydrothermal growth of ZnO nanowires in the framework of …

Signals From Intraventricular Depth Electrodes Can Control A Brain-Computer Interface, Jerry J. Shih, Dean J. Krusienski

Electrical & Computer Engineering Faculty Publications

A Brain-Computer Interface (BCI) is a device that enables severely disabled people to communicate and interact with their environments using their brain waves. Most research investigating BCI in humans have used scalp-recorded electroencephalography (EEG). We have recently demonstrated that signals from intracranial electrocorticography (ECoG) and stereotactic depth electrodes (SDE) in the hippocampus can be used to control a BCI P300 Speller paradigm. We report a case in which stereotactic depth electrodes positioned in the ventricle were able to obtain viable signals for a BCI. Our results demonstrate that event-related potentials from intraventricular electrodes can be used to reliably control the …

Optical Detection Of Melting Point Depression For Silver Nanoparticles Via In Situ Real Time Spectroscopic Ellipsometry, S. A. Little, T. Begou, R. W. Collins, S. Marsillac

Electrical & Computer Engineering Faculty Publications

Silver nanoparticle films were deposited by sputtering at room temperature and were annealed while monitoring by real time spectroscopic ellipsometry (SE). The nanoparticle dielectric functions (0.75 eV-6.5 eV) obtained by SE were modeled using Lorentz and generalized oscillators for the nanoparticle plasmon polariton (NPP) and interband transitions, respectively. The nanoparticle melting point could be identified from variations in the oscillator parameters during annealing, and this identification was further confirmed after cooling through significant, irreversible changes in these parameters relative to the as-deposited film. The variation in melting point with physical thickness, and thus average nanoparticle diameter, as measured by SE …

The Structural Performance Of Timber Connections, Daniel Coleman

Theses

This thesis sets out to assess the behaviour of mechanically fastened timber-to-timber connections. The design aspects of timber connections are described in detail, with particular emphasis on nailed connections. The effects of inherent variations in timber properties on joint behaviour are also described.

The two types of connections considered were:

■ Corbel (cantilever);

■ Splice.

For each connection type, different nail configurations, nail diameters and shaft lengths were used. Testing undertaken was conducted to investigate the influence of a number of nail configurations on a connection’s initial stiffness. The test results, presented using moment- rotation curves are also used to …

Regeneration Of Electrospun Bioresorbable Vascular Grafts: A Phenomenon Associated With Vascular Graft Properties And Macrophage Phenotypes (M1/M2), Koyal Garg

Theses and Dissertations

Macrophages (MФ) and mast cells are important cell types in the context of tissue remodeling and regeneration. Mast cells participate in the early stages of wound healing and modulate the acute inflammatory responses to biomaterials. Mast cells can secrete a myriad of different cytokines by the process of degranulation; the process of regulated secretion in which preformed contents stored in their granules are rapidly released by exocytosis. Some of these cytokines such as IL-4, IL-13 and TNF-α can modulate the MФ phenotype. Macrophages (MΦ) are innate immune cells, crucial for tissue homeostasis, presentation of foreign and self-antigens following infection/injury, pathogen …

Novel Fluorous Hybrid Surface Modification Characterized By Wetting Dynamics, Morphology And Nanomechanics, Sithara Nair

Theses and Dissertations

The surface response of a polymer substrate to external stimuli such as initial wetting is controlled by the outermost molecular layer. Thus, changes on the nanoscale may be engaged to control macroscale wetting behavior. Our work has predominantly focused on surface modification of conventional polyurethane coatings (HMDI-BD-PTMO). Studies on network constrained phase separation and facile polydimethylsiloxane surface functionalization led to the discovery of a simpler one-step and more general approach to functional polymer surfaces that we have designated as “Bottle-Brush Nanoglass” (BB-NG) after the two principle components: (a) a polyoxetane soft block “spine” with side chain “A” bristles and triethoxysilyl …

Modeling Of Low Coherence Interferometry Using Broadband Multi-Gaussian Light Sources, Paul Jansz, Steven Richardson, Graham Wild, Steven Hinckley

Research outputs 2012

Using a low coherence interferometry (LCI) model, a comparison of broadband single-Gaussian and multi-Gaussian light sources has been undertaken. For single-Gaussian sources, the axial resolution improves with the source bandwidth, confirming the coherence length relation that the resolution for single Gaussian sources improves with increasing spectral bandwidth. However, narrow bandwidth light sources result in interferograms with overlapping strata peaks and the loss of individual strata information. For multiple-Gaussian sources with the same bandwidth, spectral side lobes increase, reducing A-scan reliability to show accurate layer information without eliminating the side lobes. The simulations show the conditions needed for the resolution of …

Biomedical Image Signal Processing For Reflection-Based Imaging, Paul Jansz, Steven Richardson, Graham Wild, Steven Hinckley

Research outputs 2012

Optical coherence tomography (OCT), ultrasound and other reflection based biomedical imaging technologies involve image signal processing that is primarily a filtering, digitizing and summing process so that the tissue cross-section can be visualized. In particular, in OCT, a series of adjacent one dimensional in-vivo axial interferograms (A-scan) are summed to form a two dimensional (B-scan) reflection map or reflectogram. Further graphical combinations can add adjacent B-scan together to form three dimensional C-scans. A physician can make a subjective interpretation and evaluation from the B and/or C-scans that may lead to actions impacting on the patient’s prognosis. More objective information can …

Diffraction Of Digital Micromirror Device Gratings And Its Effect On Properties Of Tunable Fiber Lasers, Xiao Chen, Binbin Yan, Feijun Song, Yiquan Wang, Feng Xiao, Kamal Alameh

Research outputs 2012

A digital micromirror device (DMD) is a kind of widely used spatial light modulator. We apply DMD as wavelength selector in tunable fiber lasers. Based on the two-dimensional diffraction theory, the diffraction of DMD and its effect on properties of fiber laser parameters are analyzed in detail. The theoretical results show that the diffraction efficiency is strongly dependent upon the angle of incident light and the pixel spacing of DMD. Compared with the other models of DMDs, the 0.55 in. DMD grating is an approximate blazed state in our configuration, which makes most of the diffracted radiation concentrated into one …

Measurement And Simulation Of Dissolved Oxygen In Zayandehrood River, Ahmad Reza Rahsepar, Mehdi Khiadani, Mohammad Mehdi Amin

Research outputs 2012

Aims: This study aims to simulate dissolved oxygen of Zayandehrood river from regulating dam to Polle-Kalleh bridge using MIKE11 software that is a hydrodynamics and water quality model. Materials and Methods: During 5 months the samples were taken from four hydrometric stations and water quality parameters such as dissolved oxygen, pH, BOD (1 day, 3 days, 5 days, and 7 days), NH 4 , NO 3 - phosphate (PO4 3- ), and temperature were measured. Morphological and hydrological data were provided and introduced into the model. The model was calibrated and its accuracy was investigated. Results: The results indicated that …

Unidirectionally Optical Coupling From Free Space Into Silicon Waveguide With Wide Flat-Top Angular Efficiency, K Li, G Li, Feng Xiao, Fan Lu, Zhonghua Wang, A Xu

Research outputs 2012

A grating coupling scheme from free-space light into silicon waveguide with a remarkable property of wide flat-top angular efficiency is proposed and theoretically investigated. The coupling structure is composed of two cascaded gratings with a proper distance between their peak angular efficiencies. A quantitative semi-analytical theory based on coupled-mode models is developed for performance prediction and validated with the fully vectorial aperiodic Fourier modal method (a-FMM). With the theory, wide flat-top angular response is achieved and the conditions are pointed out. Proof-of-principle demonstrations show that the -1 dB angular widtha figure of merit to evaluate the flat-top performanceis broadened to …