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2014

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Full-Text Articles in Engineering

Performance Evaluation Of A Tracking Total Station As A Position Reference Fordynamic Gnss Accuracy Testing, Michael P. Sama, Timothy S. Stombaugh Jul 2014

Performance Evaluation Of A Tracking Total Station As A Position Reference Fordynamic Gnss Accuracy Testing, Michael P. Sama, Timothy S. Stombaugh

Biosystems and Agricultural Engineering Faculty Publications

The dynamic accuracy of a tracking total station (TTS) was evaluated using a rotary test fixture to determine the viability of using a TTS as a position reference for dynamic global navigation satellite-based system (GNSS) accuracy testing. Tests were performed at angular velocities ranging from 0 to 3.72 rad/s at a radius of 0.635 m. A technique was developed to determine the average latency of the TTS measurement serial data output. TTS measurements were interpolated at a GNSS sampling interval to provide a method for direct comparison between TTS and GNSS position measurements. The estimated latency from the TTS serial …


Hybrid Nanomaterial And Its Applications: Ir Sensing And Energy Harvesting, Yi-Hsuan Tseng Jul 2014

Hybrid Nanomaterial And Its Applications: Ir Sensing And Energy Harvesting, Yi-Hsuan Tseng

Doctoral Dissertations

In this dissertation, a hybrid nanomaterial, single-wall carbon nanotubes-copper sulfide nanoparticles (SWNTs-CuS NPs), was synthesized and its properties were analyzed. Due to its unique optical and thermal properties, the hybrid nanomaterial exhibited great potential for infrared (IR) sensing and energy harvesting.

The hybrid nanomaterial was synthesized with the non-covalent bond technique to functionalize the surface of the SWNTs and bind the CuS nanoparticles on the surface of the SWNTs. For testing and analyzing the hybrid nanomaterial, SWNTs-CuS nanoparticles were formed as a thin film structure using the vacuum filtration method. Two conductive wires were bound on the ends of the …


Thermoelectric Elisa For Quantification Of 8ohdg In A Microfluidic Device, Gergana Nestorova Jul 2014

Thermoelectric Elisa For Quantification Of 8ohdg In A Microfluidic Device, Gergana Nestorova

Doctoral Dissertations

This research demonstrates the feasibility of a novel method for performing thermoelectric enzyme-linked immunosorbent assay (ELISA) in a microfluidic device. The feasibility of the thermoelectric ELISA is demonstrated by measuring the concentration of 8-hydroxy 2-deoxyguanosine (8OHdG) in urine samples from amyloid precursor protein (APP) transgenic mice. The detection method is based on formation of a complex between 8OHdG and anti-8OHdG capture antibody conjugated to biotin. The complex is immobilized over the measuring junctions of a thermopile via biotin streptavidin interaction. The concentration of the analyte is determined by using enzyme linked secondary IgG antibody specific to the primary one. The …


Nanostructured Aluminum Oxide (Nao): Enhanced Fluorescence Imaging And Sensing, Xiang Li Jul 2014

Nanostructured Aluminum Oxide (Nao): Enhanced Fluorescence Imaging And Sensing, Xiang Li

Doctoral Dissertations

A new fluorescence enhancement technical platform based on nanostructured aluminum oxide (NAO) has been discovered. Experiments reveal that this new platform can enhance the fluorescence signals up to two or three orders of magnitude compared to a traditional glass substrate platform. In order to realize a large-scale arrayed fluorescence biosensing platform for high throughput applications, a rapid and cost-effective process has been developed to fabricate the micropatterned NAO of a variety of shapes. An optical characterization technology, by introducing UV light irradiance, has been found for the first time to determine if the NAO has been formed from Al and …


Micro And Nano Technology Platforms: From Cell Viability Monitoring To Fet Based Biosensing, Pushparaj D. Pathak Jul 2014

Micro And Nano Technology Platforms: From Cell Viability Monitoring To Fet Based Biosensing, Pushparaj D. Pathak

Doctoral Dissertations

Nanotechnology is a multidisciplinary field that combines science and engineering to design, synthesize, characterize and explore applications for materials and devices whose smallest functional organization in at least one dimension is on the nanometer scale. Nanotechnology is undergoing an explosive development and the extent of potential application is vast and widely diverse. In the field of human health care, nanotechnology is helping to develop novel materials and structures, which have made it possible to miniaturize many of the tools used in conventional assays. Smart biochips constructed out of these novel materials and structures are now capable of performing limited in …


Combining Site Specific Data With Geospatial Analysis To Identify Variable Rate Irrigation Opportunities In Irrigated Agricultural Fields., K. A. Miller, T. H. Lo, J. D. Luck, D. M. Heeren Jul 2014

Combining Site Specific Data With Geospatial Analysis To Identify Variable Rate Irrigation Opportunities In Irrigated Agricultural Fields., K. A. Miller, T. H. Lo, J. D. Luck, D. M. Heeren

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increasing demand for improving irrigation water use efficiency (IWUE) across irrigated croplands has producers looking for new opportunities to conserve water and maintain their crop production levels. Variable Rate Irrigation (VRI) technology may provide opportunities to enhance IWUE, but as with site-specific crop management of other crop inputs, all fields may not benefit from an approach which utilizes VRI. To consider the potential benefits of VRI, it will be necessary to examine multiple site-specific spatial data layers (e.g., crop yield, soil type/texture, and terrain) as well as the current conditions within a field using geospatial analysis techniques.

The goal of …


The Delivery Of Poly(Lactic Acid) Poly(Ethylene Glycol) Nanoparticles Loaded With Non-Toxic Drug To Overcome Drug Resistance For The Treatment Of Neuroblastoma, Jhilmil Dhulekar Jul 2014

The Delivery Of Poly(Lactic Acid) Poly(Ethylene Glycol) Nanoparticles Loaded With Non-Toxic Drug To Overcome Drug Resistance For The Treatment Of Neuroblastoma, Jhilmil Dhulekar

All Theses

Neuroblastoma is a rare cancer of the sympathetic nervous system. A neuroblastoma tumor develops in the nerve tissue and is diagnosed in infants and children.1 Approximately 10.2 per million children under the age of 15 are affected in the United States and is slightly more common in boys.1,2 Neuroblastoma constitutes 6% of all childhood cancers and has a long-term survival rate of only 15%.2-4 There are approximately 700 new cases of neuroblastoma each year in the United States. With such a low rate of survival, the development of more effective treatment methods is necessary. A number of therapies are available …


An Investigation Of The Effect Of Direct Metal Deposition Parameters On The Characteristics Of The Deposited Layers, Tarak A. Amine, Joseph William Newkirk, Frank W. Liou Jul 2014

An Investigation Of The Effect Of Direct Metal Deposition Parameters On The Characteristics Of The Deposited Layers, Tarak A. Amine, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

Multilayer direct laser deposition (DLD) is a fabrication process through which parts are fabricated by creating a molten pool into which metal powder is injected as particles. During fabrication, complex thermal activity occurs in different regions of the build; for example, newly deposited layers will reheat previously deposited layers. The objective of this study was to provide insight into the thermal activity that occurs during the DLD process. This work focused on the effect of the laser parameters of newly deposited layers on the microstructure and mechanical properties of the previously deposited layers in order to characterize these effects to …


Magnetics In Smart Grid, Qi Huang, Yuanqiang Song, Xu Sun, Lijun Jiang, Philip W.T. Pong Jul 2014

Magnetics In Smart Grid, Qi Huang, Yuanqiang Song, Xu Sun, Lijun Jiang, Philip W.T. Pong

Electrical and Computer Engineering Faculty Research & Creative Works

A revolution in power transmission and distribution, driven by environmental and economic considerations, is occurring all over the world. This revolution is spearheaded by the development of the smart grid. The smart grid is bringing profound change to both the power systems and many related industries. This paper reviews the development of the smart grid and its correlation with magnetics, including electromagnetic compatibility issue, magnetic-field-based measurement/monitoring, and magnetic energy storage/conversion. The challenge to the field of magnetics and the usage of the cutting edge magnetics technology in the development of the smart grid are discussed. This paper enables researchers in …


Correlation Between Microstructure And Thermionic Electron Emission From Os-Ru Thin Films On Dispenser Cathodes, Phillip D. Swartzentruber, Thomas John Balk, Michael P. Effgen Jul 2014

Correlation Between Microstructure And Thermionic Electron Emission From Os-Ru Thin Films On Dispenser Cathodes, Phillip D. Swartzentruber, Thomas John Balk, Michael P. Effgen

Chemical and Materials Engineering Faculty Publications

Osmium-ruthenium films with different microstructures were deposited onto dispenser cathodes and subjected to 1000 h of close-spaced diode testing. Tailored microstructures were achieved by applying substrate biasing during deposition, and these were evaluated with scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy before and after close-spaced diode testing. Knee temperatures determined from the close-spaced diode test data were used to evaluate cathode performance. Cathodes with a large {10-11} Os-Ru film texture possessed comparatively low knee temperatures. Furthermore, a low knee temperature correlated with a low effective work function as calculated from the close-spaced diode data. It is proposed …


Accurate Local Estimation Of Geo-Coordinates For Social Media Posts, Derek Doran, Swapna S. Gokhale, Aldo Dagnino Jul 2014

Accurate Local Estimation Of Geo-Coordinates For Social Media Posts, Derek Doran, Swapna S. Gokhale, Aldo Dagnino

Computer Science and Engineering Faculty Publications

Associating geo-coordinates with the content of social media posts can enhance many existing applications and services and enable a host of new ones. Unfortunately, a majority of social media posts are not tagged with geo-coordinates. Even when location data is available, it may be inaccurate, very broad or sometimes fictitious. Contemporary location estimation approaches based on analyzing the content of these posts can identify only broad areas such as a city, which limits their usefulness. To address these shortcomings, this paper proposes a methodology to narrowly estimate the geo-coordinates of social media posts with high accuracy. The methodology relies solely …


Tillamook County Waste Disposal Technology Assessment, Arvind Kumar, Ryan Menze, Joe Smith, Jerrod Thomas Jul 2014

Tillamook County Waste Disposal Technology Assessment, Arvind Kumar, Ryan Menze, Joe Smith, Jerrod Thomas

Engineering and Technology Management Student Projects

Tillamook County is a rural county straddling the Northern Oregon Coast Range with the majority of the local economy based around agriculture, timber, tourism, and fishing. As part of Tillamook County’s mission statement, they strive“to enhance the quality of life for its citizens by promoting and preserving public health and safety, maintaining a stable economy, encouraging wise use of resources, and providing services in the most efficient and cost-effective manner possible.” To that end, Tillamook County, Tillamook County Economic Development Council (TCEDC), Portland State University, Oregon State University, and Tetra Tech have undergone an evaluation and technology assessment process to …


Numerical Evaluation Of Paris-Regime Crack Growth Rate Based On Plastically Dissipated Energy, Parag G. Nittur, Anette M. Karlsson, Leif A. Carlsson Jul 2014

Numerical Evaluation Of Paris-Regime Crack Growth Rate Based On Plastically Dissipated Energy, Parag G. Nittur, Anette M. Karlsson, Leif A. Carlsson

Mechanical Engineering Faculty Publications

The crack growth rate during cyclic loading is investigated via numerical simulations. The crack advancement is governed by a propagation criterion that relates the increment in plastically dissipated energy ahead of the crack tip to a critical value. Once this critical value is satisfied, crack propagation is modeled via a node release scheme. Thus, the crack growth rate is an output from the numerical simulation. The crack growth rate predicted by the proposed scheme is compared with published experimental crack growth data in the Paris-regime for selected metals. A good match is found between the experimentally observed crack growth rates …


Development Of A Complex Synthetic Larynx Model And Characterization Of The Supraglottal Jet, Jayrin Ella Seegmiller Jul 2014

Development Of A Complex Synthetic Larynx Model And Characterization Of The Supraglottal Jet, Jayrin Ella Seegmiller

Theses and Dissertations

Voice is an important tool for communication. Consequently, voice disorders tend to severely diminish quality of life. Voice research seeks to understand the physics that govern voice production to improve treatment of voice disorders. This thesis develops a method for creating complex synthetic laryngeal models and obtaining flow data within these complex models. The method uses Computed Tomography (CT) scan data to create silicone models of the larynx. Index of refraction matching allows flow field data to be collected within a synthetic complex larynx, which had previously been impossible. A short proof-of-concept of the method is set forth. Details on …


Detailed Computational Modeling Of Laminar And Turbulent Sooting Flames, Adhiraj Dasgupta, Somesh Roy, Daniel C. Haworth Jul 2014

Detailed Computational Modeling Of Laminar And Turbulent Sooting Flames, Adhiraj Dasgupta, Somesh Roy, Daniel C. Haworth

Mechanical Engineering Faculty Research and Publications

This study reports development and validation of two parallel flame solvers with soot models based on the open-source computation fluid dynamics (CFD) toolbox code OpenF0AM. First, a laminar flame solver is developed and validated against experimental data. A semi-empirical two-equation soot model and a detailed soot model using a method of moments with interpolative closure (MOMIC) are implemented in the laminar flame solver. An optically thin radiation model including gray soot radiation is also implemented. Preliminary results using these models show good agreement with experimental data for the laminar axisymmetric diffusion flame studied. Second, a turbulent flame solver is developed …


A Framework Of Effective Debris Management For A Resilient Community, Jooho Kim Jul 2014

A Framework Of Effective Debris Management For A Resilient Community, Jooho Kim

Open Access Theses

Natural disasters have an enormous physical impact on communities and generate a huge volume of debris. The amount of debris is almost five to ten times higher than the annual solid waste volume in a community, and slow debris removal can hinder both emergency response and proceeding with the tasks of recovery. The cost of debris management also can reach more than 27% of the total disaster recovery costs. Therefore, debris management teams have considerable challenges in removing disaster debris. ^ This thesis introduces a framework for an effective debris management plan based on the interrelationship between critical infrastructure systems …


Experimental Study Of Unsteady Heat Release In An Unstable Single Element Lean Direct Injection (Ldi) Gas Turbine Combustor, Varun S. Lakshmanan Jul 2014

Experimental Study Of Unsteady Heat Release In An Unstable Single Element Lean Direct Injection (Ldi) Gas Turbine Combustor, Varun S. Lakshmanan

Open Access Theses

In an effort to curb emissions from gas turbine engines, many low emission engine concepts have been developed. Among the most promising of these is the LDI (Lean Direct Injection). These systems operate at relatively low equivalence ratios close to blowout and are prone to instabilities. Combustion instabilities can reduce the life of the combustor by causing large pressure fluctuations and enhanced heat release to the walls of the combustor and reduce the efficiency of the engines. The understanding of combustion instabilities is vital to the implementation of such systems. Combustion instabilities are studied in an self-excited single element gas …


Physical And Chemical Attributes Of A Genetically Modified Fruit Pectin, Carl Patrick Littrell Jul 2014

Physical And Chemical Attributes Of A Genetically Modified Fruit Pectin, Carl Patrick Littrell

Open Access Theses

Pectin is an important polymer used in the food industry as a thickening and gelling agent. Though pectin is ubiquitous in plants, chemical and structural differences among pectin molecules prevent most from being viable for industrial use. Enzymes found naturally in fruit cell walls during the ripening process impair many desirable attributes of fruit pectins, rendering them unsuitable for industrial applications. Pectin methylesterase (PME) is one such enzyme whose expression can be altered during ripening through the use of recombinant genetic engineering. Reduction in levels of PME results in increased degree of methylation and molecular size of pectin, greatly increasing …


Weld Pool And Keyhole Dynamic Analysis Based On Visual System And Neural Network During Laser Keyhole Welding, Masiyang Luo Jul 2014

Weld Pool And Keyhole Dynamic Analysis Based On Visual System And Neural Network During Laser Keyhole Welding, Masiyang Luo

Open Access Theses

In keyhole fiber laser welding processes, the weld pool behavior and keyhole dynamics are essential to determining welding quality. To observe and control the welding process, the accurate extraction of the weld pool boundary as well as the width is required. In addition, because of the cause-and-effect relationship between the welding defects and stability of the keyhole, which is primarily determined by keyhole geometry during the welding process, the stability of keyhole needs to be considered as well.^ The first part of this thesis presents a weld pool edge detection technique based on an off axial green illumination laser and …


Assessment Of Noise Metrics For Application To Rotorcraft, Andrew L. Mcmullen Jul 2014

Assessment Of Noise Metrics For Application To Rotorcraft, Andrew L. Mcmullen

Open Access Theses

It is anticipated that the use of rotorcraft passenger vehicles for shorter journeys will increase because their use can reduce the time between boarding and take-off. The characteristics of rotorcraft noise are very different to that of fixed wing aircraft. There can be strong tonal components, fluctuations that can also make the noise sound impulsive, and future rotorcraft may produce proportionally more low frequency noise content. Most metrics that are used today to predict noise impact on communities around airports (e.g., Ldn) are just functions of A-weighted sound pressure level. To build a better noise annoyance model that …


Nickel Aluminum Shape Memory Alloys Via Molecular Dynamics, Keith Ryan Morrison Jul 2014

Nickel Aluminum Shape Memory Alloys Via Molecular Dynamics, Keith Ryan Morrison

Open Access Theses

Shape memory materials are an important class of active materials with a wide range of applications in the aerospace, biomedical, and automobile industries. These materials exhibit the two unique properties of shape memory and superelasticity. Shape memory is the ability to recover its original shape by applying heat after undergoing large deformations. Superelasticity is the ability to undergo large, reversible deformations (up to 10%) that revert back when the load is removed. These special properties originate from a reversible, diffusionless solid-solid phase transformation that occurs between a high temperature austenite phase and a low temperature martensite phase. The development of …


Preparation & Characterization Of High Purity Cu2 Znsn(Sxse1-X)4 Nanoparticles, Bethlehem G. Negash Jul 2014

Preparation & Characterization Of High Purity Cu2 Znsn(Sxse1-X)4 Nanoparticles, Bethlehem G. Negash

Open Access Theses

Research in thin film solar cells applies novel techniques to synthesize cost effective and highly efficient absorber materials in order to generate electricity directly from solar energy. Of these materials, copper zinc tin sulfoselenide (Cu2ZnSn(SxSe1-x) 4) nanoparticles have shown great promise in solar cell applications due to optimal material properties as well as low cost & relative abundance of materials.1,2 Sulfoselenide nanoparticles have also a broader impact in other industries including electronics3, LED 4, and biomedical research5. Of the many routes of manufacturing these class of semiconductors, …


Synthesis And Characterization Of Crystalline Iron Nanoparticles From Zerovalent Iron Sandwich Complexes, Anh Tue Nguyen Jul 2014

Synthesis And Characterization Of Crystalline Iron Nanoparticles From Zerovalent Iron Sandwich Complexes, Anh Tue Nguyen

Open Access Theses

In this project we present a systematic study on the synthesis of crystalline iron nanocubes by thermal decomposition of an iron sandwich complex, ( π-C5H5)Fe0(π-C 6H7), in the presence of oleylamine and oleylamine.HCl as surfactants and n-decane as a solvent. The presence of oleylamine.HCl is essential for the reproducible formation of crystalline iron cores.^ Reaction parameters such as temperature, surfactant concentration, effect of counterion, and organoiron reagent structure were investigated in order to obtain iron nanoparticles with uniform size and shape. The nanoparticles, which were characterized by …


Comparative Lca Of Stand-Alone Power Systems Applied To Remote Cell Towers, Eduardo Olmeda Noguera Jul 2014

Comparative Lca Of Stand-Alone Power Systems Applied To Remote Cell Towers, Eduardo Olmeda Noguera

Open Access Theses

Remote cell towers need on-site power generation or stand-alone power systems for operation and, traditionally, diesel electric generators have been used as backup power systems in combination with renewable energies. Currently, Polymer Electrolyte Membrane Fuel Cells (PEMFC's) are emerging as substitutes for the diesel electric generator, because of their reliability, high-energy conversion efficiency and zero emissions while operating.^ However, very few studies have compared the environmental impact of these two technologies, especially on remote cell tower applications. As PEMFC's have no emissions while operating, concerns about their environmental impact surge because of the use of rare and high processed materials, …


Differences In Carbon Dioxide Evolution From Samples Of Shelled Corn Subjected To Various Storage Treatments, Cininta Alp Pertiwi Jul 2014

Differences In Carbon Dioxide Evolution From Samples Of Shelled Corn Subjected To Various Storage Treatments, Cininta Alp Pertiwi

Open Access Theses

Shelled corn was collected from two sources - commercial grain elevators and corn harvested from Purdue University farms and then frozen until tested. Using a carbon dioxide (CO2) test kit manufactured by Woods End Laboratories, CO2 evolution measurements were conducted on shelled corn from both sources, after the samples were re-wetted to approximately 21% moisture content, placed in a 473 ml glass jar, and incubated at room temperature for 72 hours. The CO2 test kit uses a gel that changes color in response to a change in the level of CO2 in the surrounding air. …


Big Data Analytics With Nyc Taxicab Data, Xinwu Qian Jul 2014

Big Data Analytics With Nyc Taxicab Data, Xinwu Qian

Open Access Theses

In recent years, the fast development of pervasive computing technologies gives us access to a variety of big data sources, such as mobile phone users, bank note movements and twitter posts etc. It provides unprecedented opportunities to conduct urban studies and contributes to the sustainable and efficient development of large cities. While big data is an invaluable treasure, our knowledge is limited due to lack of appropriate tools to analyze the data. Hence, this thesis is mainly focused on demonstrating how taxicab data can be used to study urban travel patterns and explore useful insights.


Paxos Based Directory Updates For Geo-Replicated Cloud Storage, Srivathsava Rangarajan Jul 2014

Paxos Based Directory Updates For Geo-Replicated Cloud Storage, Srivathsava Rangarajan

Open Access Theses

Modern cloud data stores (e.g., Spanner, Cassandra) replicate data across geographically distributed data centers for availability, redundancy and optimized latencies.^ An important class of cloud data stores involves the use of directories to track the location of individual data objects. Directory-based datastores allow flexible data placement, and the ability to adapt placement in response to changing workload dynamics. However, a key challenge is maintaining and updating the directory state when replica placement changes.^ In this thesis, we present the design and implementation of a system to address the problem of correctly updating these directories. Our system is built around JPaxos, …


Experimental Characterization Of The Pt Asymmetry With Balanced Inflow And Outflow At Different Reynolds Numbers, Zijie Qu Jul 2014

Experimental Characterization Of The Pt Asymmetry With Balanced Inflow And Outflow At Different Reynolds Numbers, Zijie Qu

Open Access Theses

This research focused on characterizing the PT asymmetry with balanced inflow and outflow conditions at different Reynolds number using experimental method. The characterization process utilized PIV data to explore the relationship between PT asymmetry and Reynolds number in two different experiments. In the first experiment, balanced inflow and outflow are used to generate the flow field in a cuboid test section with different Reynolds number, the inflow and outflow are located at the central of left side and right side of the test section. In the second experiment, a main flow is introduced to the first experiment by adding another …


The Effects Of Chronic Neural Implantation On Localized Vasculature, Andrew L. Ready Jul 2014

The Effects Of Chronic Neural Implantation On Localized Vasculature, Andrew L. Ready

Open Access Theses

Prosthetic solutions currently available range from simple devices intended for aesthetics purposes to complex systems attempting to restore lost function and sensation; of these methods, none show more promise in restoration of normal function and life satisfaction than neural prosthetics. These devices directly interface with the nervous system in order to restore realistic function and feeling to the patient, potentially returning them to how their life once was. While in some cases patients requiring prosthetics can utilize peripheral nerves, those who suffer from injuries or disease which cause damage to the central nervous system can necessitate the usage of devices …


Impinging Jet Spray Formation Using Non-Newtonian Liquids, Neil S. Rodrigues Jul 2014

Impinging Jet Spray Formation Using Non-Newtonian Liquids, Neil S. Rodrigues

Open Access Theses

Over the past two decades there has been a heightened interest in implementing gelled propellants for rocket propulsion, especially for hypergolic bi-propellants such as monomethylhydrazine (MMH) and nitrogen tetroxide oxidizer (NTO). Due to the very high level of toxicity of hypergolic liquid rocket propellants, increasing safety is an important area of need for continued space exploration and defense operations. Gelled propellants provide an attractive solution to meeting the requirements for safety, while also potentially improving performance. ^ A gelling agent can be added to liquid propellants exhibiting Newtonian behavior to transform the liquid into a non-Newtonian fluid with some solid-like …