Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

2019

Theses/Dissertations

Open Access Theses & Dissertations

Articles 61 - 70 of 70

Full-Text Articles in Engineering

Load Rating Mobility As A Framework For Bridge Owners, Bryan Keith Stephens Jan 2019

Load Rating Mobility As A Framework For Bridge Owners, Bryan Keith Stephens

Open Access Theses & Dissertations

In this time of financial economy, bridge owners are faced with the important decision of where to focus financial assets while attempting to determine which structures are in most need. Bridge Engineers and researchers alike agree that a large portion of the United States bridge population are reaching the end of their design life. Researchers are currently investigating various means and methods of lengthening the amount of usefulness of these key pieces of infrastructure. This paper introduces the novel idea of bridge Load Rating Mobility and how it can be leveraged by stake holders to assist in making those financial …

Go to article

Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa Jan 2019

Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa

Open Access Theses & Dissertations

Nanotechnology has a great potential in ensuring food production, security and safety globally. Over the past decade, research on the use of nanomaterials to supply nutrient elements and protect plants from pest and diseases has significantly increased. Tomato (Solanum lycopersicum) is one of the most consumed vegetables in the world and United State is one of its largest producers globally generating billions of dollars annually in revenue.. Tomato plants are affected worldwide by Fusarium wilt caused by Fusarium oxysporum f. sp. Lycopersici. There is growing concern about excessive use of conventional pesticides in controlling Fusarium and other diseases in tomato …

Go to article

Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete Jan 2019

Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete

Open Access Theses & Dissertations

Unprecedented levels of production and consumption have caused a rapid exhaustion of the Earth's virgin resources, which is coupled with a fast accumulation of contaminants in the form of solid waste, especially in landfills. Two significant landfill constituents come from textile waste and discarded plastic bottles. Since there is a finite amount of space that can be feasibly used for landfills, solutions that make use of these post-consumer products are imperative. This study presents one possible solution by using surface modifications of cotton fibers to produce a natural fiber-reinforced polymer composite (NFRPC) from post-consumer textile waste and polyethylene terephthalate (PET) …

Go to article

Applications Of A New Genetic Algorithm To Solve The Centralized Carrier Collaboration And Multihub Location Problem Considering Environmental Impacts, Eduardo Jose Castillo Fatule Jan 2019

Applications Of A New Genetic Algorithm To Solve The Centralized Carrier Collaboration And Multihub Location Problem Considering Environmental Impacts, Eduardo Jose Castillo Fatule

Open Access Theses & Dissertations

The Centralized Carrier Collaboration and Multi-hub Location Problem (CCCMLP) represents a strategy that small-to-medium sized less-than-truckload (LTL) carrier companies can use in order to improve their profit margins. It is a strategy that is being explored in order to make these companies more sustainable as they are forced to reinvent their processes and supply chains. In this work, I will present a metaheuristic approach to optimizing their hub establishment and routing policies in order to better their expected profit margins and reduce their environmental impacts. The study considers the costs of transportation, loading and unloading, maintenance, operations, and inventory holding …

Go to article

Comparative Study Of Analytical Models Of The Gruneisen Parameter Of Metals As Function Of Pressure, Celia Garcia Amparan Jan 2019

Comparative Study Of Analytical Models Of The Gruneisen Parameter Of Metals As Function Of Pressure, Celia Garcia Amparan

Open Access Theses & Dissertations

Commonly used Gruneisen parameter (γ) models only hold accurate in limited regimes making them inapplicable for use over wide temperature-pressure conditions. The accuracy of these analytical models of γ and of the thermal expansion of solids are of particular interest as these are considered proxies for quantifying anharmonicity, which may be a significant contribution to the thermal pressure at high temperatures. This work reviews various definitions of γ and their relations to the equations of state and apply them to two simple metals: Tantalum (Ta) and Copper (Cu), for which a high body of experimental data exists. Classical Molecular Dynamics …

Go to article

Conductivity Modulation In Strained 2d Transition- Metal- Dichalcogenides Via Micro- Electro- Mechanical Actuation, Aldo Ivan Vidaña Jan 2019

Conductivity Modulation In Strained 2d Transition- Metal- Dichalcogenides Via Micro- Electro- Mechanical Actuation, Aldo Ivan Vidaña

Open Access Theses & Dissertations

In this thesis, strain-induced conductivity modulation in bi-layer molybdenum disulfide (MoS2) flakes is experimentally investigated and modeled. Uniaxial tensile strain in the MoS2 flakes is achieved using a micro-electro-mechanical (MEM) actuator. Conductivity ratios up to 400 are demonstrated. Theoretical predictions of conductivity versus applied voltage in the MEMS-MoS2 device match experimental data reasonably well using only the effective width of the TMDC flakes as the sole fitting parameter. The amount of strain induced in the MoS2 flakes was determined to be as high as 2.7% for one flake using the model fitted to the experiment data. The switching energy required …

Go to article

Exploration And Optimization Of Biomaterials And Cells Required For The Fabrication Of A "Cardiac Patch", Shweta Anil Kumar Jan 2019

Exploration And Optimization Of Biomaterials And Cells Required For The Fabrication Of A "Cardiac Patch", Shweta Anil Kumar

Open Access Theses & Dissertations

Cardiac failure induced by myocardial infarction is believed to be one of the primary causes of morbidity and mortality all over the world. Affecting more than 26 million people worldwide, its prevalence has been observed to increase steadily. Myocardial infarction, which intitially begins as the occlusion of of a coronary artery, results in the death of millions of cardiomyocytes by obstructing blood flow to the serviced regions of the myocardium. The dead myocardium is replaced by a dense,collagenous scar which reduces the contractility of the heart, gradually leading to heart attacks. Most of the existing treatment therapies are palliative in …

Go to article

Development Of An Ionic Green Monopropellant 1 Newton Thruster For Small Satellite Application, Jaclyn Mona Mejia Jan 2019

Development Of An Ionic Green Monopropellant 1 Newton Thruster For Small Satellite Application, Jaclyn Mona Mejia

Open Access Theses & Dissertations

In effort to advance green monopropellant propulsion using AF-M315E, a 1N thruster was developed to demonstrate the propellant capabilities for low thrust requirement missions. The current study presents the development of a 1 Newton thruster. The thruster was designed based on available literature for initial parameters. In house developed catalyst was packed into the 1 Newton thruster, and mounted onto a thrust stand for testing. Two configurations of catalyst were used for this testing campaign. As a result, temperature peaks from AF-M315E decomposition gases reached up to 1400°C with an iridium loading factor of 25% by mass with both catalyst …

Go to article

Hfo Detector Based On Eeg Mean Energy Change Detection, Raul Ontiveros Jan 2019

Hfo Detector Based On Eeg Mean Energy Change Detection, Raul Ontiveros

Open Access Theses & Dissertations

The main goal of this work is to support automated seizure prediction by identifying preictal states using multiple detectors of high-frequency oscillations (HFOs). Assessment of HFOs from a seizure onset zone may be facilitated using automatic HFO detectors. However, studies have shown that HFOs can be generated by physiological or pathological brain processes. Distinguishing between pathological and physiological HFOs is challenging due to a lack of discriminant information in signals' morphology and other characteristics. Other complicating factors include a lack of consistency in definitions of HFO frequency ranges, the need for expert verification of HFO detection, and lack of robustness …

Go to article

Raman Computational And Experimental Studies On Label-Free Biological Investigations, John Ciubuc Jan 2019

Raman Computational And Experimental Studies On Label-Free Biological Investigations, John Ciubuc

Open Access Theses & Dissertations

Raman spectroscopy is an optical technique that allows for label-free biological investigations to take place. This approach presents both new perspectives and a means for visualizing investigations. This thesis confronts two biological cases: dopamine (DA) detection at physiological levels and assessment of renal osteodystrophy (ROD). We employed surface-enhanced Raman spectroscopy on silver nanoparticles recording DA concentrations as low as 10−11 molar. Quantum chemical density functional calculations were carried out using Gaussian-09 analytical suite software. Good agreement between the simulated and experimentally determined results indicates the existence of distinct DA molecular forms, such as uncharged DA±, anionic DA−, and dopaminequinone. Disappearance …

Go to article

First Prev