Engineering Commons^™

Analytical Modeling Of A Novel Microdisk Resonator For Liquid-Phase Sensing: An All-Shear Interaction Device (Asid), Mohamad Sadegh Sotoudegan

Dissertations (1934 -)

Extensive research on micro/nanomechanical resonators has been performed recently due to their potential to serve as ultra-sensitive devices in chemical/biosensing. These applications often necessitate liquid-phase sensing, introducing significant fluid-induced inertia and energy dissipation that reduces the resonator’s performance. To minimize the detrimental fluid effects on such devices, a novel microdisk resonator supported by two tangentially-oriented, axially-driven “legs” is investigated analytically and effects of the system parameters on the resonator/sensor performance are explored. Since the device surface vibrates primarily parallel to the fluid-structure interface, it is referred to here as an “all-shear interaction device,” or ASID. Analytical modeling of the ASID …

Nano Clay-Enhanced Calcium Phosphate Cements And Hydrogels For Biomedical Applications, Udayabhanu Jammalamadaka

Doctoral Dissertations

Biomaterials are used as templates for drug delivery, scaffolds in tissue engineering, grafts in surgeries, and support for tissue regeneration. Novel biomaterial composites are needed to meet multifaceted requirements of compatibility, ease of fabrication and controlled drug delivery. Currently used biomaterials in orthopedics surgeries suffer limitations in toxicity and preventing infections. Polymethyl methacrylate (PMMA) used as bone cement suffers from limitations of thermal necrosis and monomer toxicity calls for development of better cementing biomaterials. A biodegradable/bioresorbable cement with good mechanical properties is needed to address this short coming. Metal implants used in fixing fractures or total joint replacement needs improvements …

Investigation Of Small-Scale Thermal Recovery And Storage Systems, Suvhashis Thapa

Doctoral Dissertations

An approach to recover and store waste heat is presented in this dissertation. The waste heat is the energy that is rejected to the environment without being put to practical use and it is a result of both equipment inefficiency and thermodynamic limitation on the equipment and the process. In a typical Otto cycle, for instance, out of the total energy consumed by the system, only one-third of the energy is converted into useful work and the rest is discharged in the environment as waste heat [1]. For a spark ignition, a 1.4 liters internal combustion engine with the thermal …

Unmanned Vehicles Formation Control In 3d Space And Cooperative Search, Saba Ramazani

Doctoral Dissertations

The first problem considered in this dissertation is the decentralized non-planar formation control of multiple unmanned vehicles using graph rigidity. The three-dimensional formation control problem consists of n vehicles operating in a plane Q and r vehicles that operate in an upper layer outside of the plane Q. This can be referred to as a layered formation control where the objective is for all vehicles to cooperatively acquire a predefined formation shape using a decentralized control law. The proposed control strategy is based on regulating the inter-vehicle distances and uses backstepping and Lyapunov approaches. Three different models, with increasing …

Studies On The Electrical Transport Properties Of Carbon Nanotube Composites, Taylor Warren Tarlton

Doctoral Dissertations

This work presents a probabilistic approach to model the electrical transport properties of carbon nanotube composite materials. A pseudo-random generation method is presented with the ability to generate 3-D samples with a variety of different configurations. Periodic boundary conditions are employed in the directions perpendicular to transport to minimize edge effects. Simulations produce values for drift velocity, carrier mobility, and conductivity in samples that account for geometrical features resembling those found in the lab. All results show an excellent agreement to the well-known power law characteristic of percolation processes, which is used to compare across simulations. The effect of sample …

Use Of Recycled Crushed Concrete (Rcc) Fines For Potential Soil Stabilization, Lindeman Mark, Varilek Brandon, Lieska Halsey, Rick Gloe, Maria Olomi

Nebraska Department of Transportation: Research Reports

This study evaluated the use of Recycled Crushed Concrete (RCC) Fines for potential soil stabilization. Soil stabilization is the enhancement of subgrade stability to improve the constructability of successive pavement layers. Use of RCC fines may not only provide less costly alternatives for subgrade stabilization, but their use may also alleviate landfill disposal challenges.

Windswept: Tailwinds, Headwinds, Crosswinds - Oh My!, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Development And Evaluation Of Custom Prosthetic Devices For A Companion Animal Utilizing Additive Manufacturing., Benjamin Joseph Cahill

Electronic Theses and Dissertations

BACKGROUND AND SIGINIFICANCE: Few options exist for companion animals in need of prosthetic devices. With the rise of rapid prototyping technology, the availability and customization of prosthetic devices for individual companion animals is now a viable and cost effective alternative to the current options of a peg leg prosthetic, or wheel-assisted prosthetic device. The goals of this study were to describe the (1) specific needs and (2) biomechanics of a feline with bilateral thoracic limb amputation, (3) develop custom prosthetic devices utilizing rapid prototyping technology, and (4) describe the biomechanics of a feline with bilateral thoracic limb amputation using the …

Cermet Development For High Temperature And High Pressure Applications, Beatriz Justus Ferez, Samantha Guthrie, Brian J. Jaques (Mentor), Darryl P. Butt (Mentor)

Idaho Conference on Undergraduate Research

Many traditionally used low cost alloys are easily corroded in steam or supercritical CO₂. An effective solution is to utilize ceramic heat exchangers that are often integrated with metallic components which result in a significant thermal expansion mismatch. The goal of this project is to develop a sealing method to create a hermetic joint between the ceramic and metal alloy. Proposed is a seal ring containing a cermet powder with a coefficient of thermal expansion (CTE) higher than the ceramic and metal to produce a high temperature compressive seal. Cermets of Ag and MgO have been selected to …

Computational Studies Of Grain Boundary Behavior In Uranium Dioxide Nuclear Fuels, Eric Nelson, Lan Li (Mentor), Simon C. Middleburgh (Mentor)

Idaho Conference on Undergraduate Research

Nuclear power is responsible for the production of 380,000 Megawatts of energy worldwide, which results in over 11% of the world’s energy production [world-nuclear.org]. Pellet-cladding interactions (PCI) are a key nuclear fuel failure mechanism which presents formidable challenges to researchers due to extreme nuclear fission conditions. Although PCI interactions have been reduced due to fuel additives, understandings of PCI interactions remain elusive. We propose new approaches to increase understanding of nuclear fuel interactions; specifically, uranium dioxide and the effects of dopants. This study focuses on amorphous uranium dioxide and fission products, while benchmarking new methods with previous computational studies. Results …

The Effects Of Antenna Coupling In A Mimo Radar System, Benjamin T. Arnold

Theses and Dissertations

A mathematical model for a multiple-input multiple-output radar system is presented. The model is used to track signals through the system in order to identify the impact of antenna array mutual coupling on radar system performance. Simulations using the model provide quantitative assessment of the performance degradation as a function of antenna coupling strength. Specifically, the results show that coupling can cause a target to appear at an angle notably different than its actual angle and can cause an increase in the side lobe level. A compensation technique is presented that completely removes these effects for practical levels of coupling. …

The Derivation Of Sea Surface Velocities From Satellite Imagery Using Maximum Cross Correlation (Mcc), Philip Lawrence

The Plymouth Student Scientist

An investigation into the use of cross-correlation statistics to resolve surface velocities from satellite imagery was conducted for the region characterised by the Benguela current at approximately 24oS - 28oS and 9oE - 17oE for July 14th and 15th 2011. Colour images depicting concentrations for chlorophyll_a taken by the MODIS sensor and provided by NASA’s Ocean Color Browser, were used to conduct the statistical analysis using distinguishable surface colour features as tracers. Three runs using different parameter values for the cross correlation were carried out and the output vector fields examined. The first run produced 126 vectors with mean u …

Investigation Of Fate And Migration Of Hexavalent Chromium At The Mouat Industries Site, Columbus, Montana, Harwood Jeremy

Graduate Theses & Non-Theses

Human impacts to water resources occur in a variety of instances and are often associated with, but not limited to, nor always a result of, industrial processes. Manufacturing of Cr compounds for use as a corrosion inhibitor require the transformation of Cr into a toxic state, requiring extreme safety and caution during processing and handling.

Historical processing of chromite ore at the Mouat Industries site led to Cr-contaminated groundwater within the city limits of Columbus, MT. After the site was listed on the Environmental Protection Agency’s National Priority List in 1986, soil remediation was conducted at the site in 1994. …

Development Of Two Pdci Damping Controller Supervisory Elements, James Colwell

Graduate Theses & Non-Theses

Long transmission lines create opportunities for synchronous generators to oscillate or swing against one another at frequencies known as inter-area modes that are well observed. Some modes become less damped during times of heavy loading on the power system. Due to these modes, transmission systems are generally constrained by dynamic limits. Approaches to improve system damping are being researched. One method being evaluated is modulating power flows on the Pacific Direct Current Intertie (PDCI). A derivative feedback control system using phasor measurement unit (PMU) data has been shown in simulation to improve system damping. However, any feedback control scheme utilized …

Vertical Implementation Of Cloud For Education (V.I.C.E.), Travis S. Brummett

Masters Theses & Specialist Projects

There are several different implementations of open source cloud software that organizations can utilize when deploying their own private cloud. Some possible solutions are OpenNebula, Nimbus, and Eucalyptus. These are Infrastructure-as-a-Service (IaaS) cloud implementations that ultimately gives users virtual machines to undefined job types. A typical IaaS cloud is composed of a front-end cloud controller node, a cluster controller node for controlling compute nodes, a virtual machine image repository node, and many persistent storage nodes and compute nodes. These architectures are built for ease of scalability and availability.

Interestingly, the potential of such architectures could have in the educational field …

Effect Of Precipitation Aging Temperatures On Rejuvenation Heat Treated Microstructures, Hardness And Γ' Phase Stability In Udimet-500, C Niemkong, S Polsilapa, P Wangyao

Journal of Metals, Materials and Minerals

This research has studied the effect of precipitation aging temperatures on size and area density of γ' particles of the reheat treated microstructures incast nickel basesuperalloy, grade Udimet-500. All specimens were performed the same solutioning treatment at temperature of 1,150ºC for 4 hours following with various precipitation aging temperatures of 760, 780, 800 and 820ºC for 16 hours. Furthermore, these reheat treated specimens were also performed long-term heating at temperatures of 900ºC and 1000ºC for 200 hours to evaluate γ'-phase stability. Finally, hardness measurements were also carried out. Form all obtained results, it was found that the standard precipitation aging …

Experimental Investigation And Numerical Simulation Of A Copper Micro-Channel Heat Exchanger With Hfe-7200 Working Fluid, Eric Borquist

Doctoral Dissertations

Ever increasing cost and consumption of global energy resources has inspired the development of energy harvesting techniques which increase system efficiency, sustainability, and environmental impact by using waste energy otherwise lost to the surroundings. As part of a larger effort to produce a multi-energy source prototype, this study focused on the fabrication and testing of a waste heat recovery micro-channel heat exchanger. Reducing cost and facility requirements were a priority for potential industry and commercial adoption of such energy harvesting devices. During development of the micro-channel heat exchanger, a new fabrication process using mature technologies was created that reduced cost, …

Three-Dimensional Printing And Nanotechnology For Enhanced Implantable Materials, Karthik Kumar Tappa

Doctoral Dissertations

Orthopedic and oro-maxillofacial implants have revolutionized treatment of bone diseases and fractures. Currently available metallic implants have been in clinical use for more than 40 years and have proved medically efficacious. However, several drawbacks remain, such as excessive stiffness, accumulation of metal ions in surrounding tissue, growth restriction, required removal/revision surgery, inability to carry drugs, and susceptibility to infection. The need for additional revision surgery increases financial costs and prolongs recovery time for patients. These metallic implants are bulk manufactured and often do not meet patient's requirements. A surgeon must machine (cut, weld, trim or drill holes) them in order …

Experimental And Numerical Evaluation Of A New Composite Pressure Pipe For A Trenchless Rehabilitation Technology, Xuanchen Yen

Doctoral Dissertations

The information presented in this dissertation is based on research work conducted at Trenchless Technology Center (TTC) at Louisiana Tech University. This work was performed through a contract with China University of Geoscience (CUG) for a gas company. China's gas pipelines need replacement or rehabilitation after 15 to 30 years of service. China's gas industry is looking for suitable techniques to transfer into their market.

When compared to conventional excavation pipeline renewal or replacement methods, there are obvious advantages of TRT for gas pipelines that can impact the triple bottom-line of economic, social and environmental benefits. An introduction of TRT …

In-Network Retransmissions In Named Data Networking, Hila Ben Abraham, Patrick Crowley

All Computer Science and Engineering Research

The strategy layer is an important architectural component in both Content-Centric Networking (CCN) and Named Data Networking (NDN). This component introduces a new forwarding model that allows an application to configure its namespace with a forwarding strategy. A core mechanism in every forwarding strategy is the decision of whether to retransmit an unsatisfied Interest or to wait for an application retransmission. While some applications request control of all retransmissions, others rely on the assumption that the strategy will retransmit an Interest when it is not satisfied. Although an application can select the forwarding strategy used in the local host, it …

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Electrical and Computer Engineering Faculty Publications

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii) …

Privacy And The Information Age: A Longitudinal View, Charles E. Downing

Journal of International Technology and Information Management

As information systems and data storage capacity become increasingly sophisticated, an important ethical question for organizations is “What can/will/should be done with the personal information that has been and can be collected?” Individuals’ privacy is certainly important, but so is less costly and more targeted business processes. As this conflict intensifies, consumers, managers and policy makers are left wondering: What privacy principles are important to guide organizations in self-regulation? For example, do consumers view the five rights originally stated in the European Data Protection Directive as important? Comprehensive? Is there a product discount point where consumers would forsake these principles? …

An Empirical Investigation On Ceo Turnover In It Firms And Firm Performance, Peiqin Zhang, David Wierschem, Francis A. Mendez Mediavilla, Keejae P. Hong

Journal of International Technology and Information Management

Drawn upon upper echelon theory and organizational theory, this research proposes to examine the impact of CEO turnover in IT firms on firm performance in terms of both sustainable accounting performance and market performance. We find that CEO turnover is a significant determinant of firm performance, especially in IT firms. This paper contributes to the IS literature by investigating the CEO turnover impact in IT firms compared to other industries. This study also has practical implications by providing the guideline for IT firms on the CEO turnover policy. Such firms should place additional emphasis on their succession planning efforts.

Facebook Use Among African American And Hispanic Students: An Exploratory Investigation Of Perceived Academic Impact, Sathasivam Mathiyalakan, Sharon D. White, Jorge O. Brusa

Journal of International Technology and Information Management

Facebook is one of the world’s leading social networking sites. It is pervasive in students’ lives and can impact their academic careers in a variety of ways. However, little research exists evaluating the use of Facebook in minority academic settings. An early step in this direction is to gain an understanding of how different student demographic groups use Facebook. An interest in further assessment of Facebook’s role in diverse segments of academia motivates the collection and analysis of Facebook-related data from minority serving institutions such as Historically Black Colleges or Universities (HBCUs) and Hispanic Serving Institutions (HSIs). This study presents …

The Eco-Friendly Intermodal Delivery Network, Sergio Mourelo

Senior Honors Theses

The design of the distribution process is a strategic issue for almost every company. As the use of advanced technology and automation increases in manufacturing and logistics, the implementation of autonomous and electrical transportation, such as driverless vehicles and electric trucks, has become an interesting topic of study within the last few years, with the main objective of minimizing distribution costs and delivery times. The purpose of this research is to prove that intermodal delivery networks, which may combine a train and several electric vehicles, are more efficient and environmentally friendly than unimodal networks for high volume and long haul …

Formation Of Phase Icosahedral And Decagonal Quasicrystalline Alloys Al62,2cu25,3fe12,5/Al65ni15co20 Influence On The Oxidation, Lcla Jamshidi, Rj Rodbari, L Nascimento

Journal of Metals, Materials and Minerals

In this article we will cover a study of the formation of icosahedral and decagonal phases two quasicrystals Al62,2Cu25,3Fe12,5 And Al65Ni15Co20,and the influence of oxidation in this alloy. For this purpose research used the diffraction of X-ray (XRD), scanning electron microscopy (SEM)/Energy Dispersive Spectroscopy (EDS), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TG) .The results displayed found aspects of morphological structural as well as the surface of the two compositions of quasicrystals, these were prepared and obtained in electric arc furnaces and induction and arc. Oxidation of Al62,2Cu25,3Fe12,5 alloy, intermetallic phases presented with combinations of alloying elements and above 675C …

X-Ray Attenuation Of Cotton Fabrics Coated With Barium Sulphate, B Kusuktham, C Wichayasiri, S Udon

Journal of Metals, Materials and Minerals

The x-ray attenuation performance of barium sulphate coated cotton fabrics was evaluated. 10-50 wt% barium sulphate/binder mixture was prepared and then coated onto cotton fabrics. For x-ray shielding evaluation, the fabrics with the different layers were tested under the x-ray radiation at 50kV-100 kV energy levels. The results showed that the shielding x-ray radiation were in the range of 1.48-77%, indicating that x-ray attenuation significantly increased with an increase in BaSO4 content. In addition, the number of fabric layers also played an important role. Finally, it was found that BaSO4 coated cotton fabrics exhibited satisfactory durability with respect to rubbing …

The Fcc And The “Pre-Internet”, John Blevins

Indiana Law Journal

Network neutrality has dominated broadband policy debates for the past decade. While important, network neutrality overshadows other policy levers that are equally important to the goals of better, cheaper, and more open broadband service. This lack of perspective has historical precedent—and understanding this history can help refocus today’s policy debate. In the 1960s and 1970s, telephone companies threatened the growth of the nascent data industry. The FCC responded with a series of rulemakings known as the “Computer Inquiries” proceedings. In the literature, Computer Inquiries enjoys hallowed status as a key foundation of the Internet’s rise.

This Article, however, argues that …

Comparison Of Airfoil Precomputational Analysis Methods For Optimization Of Wind Turbine Blades, Ryan Barrett, Andrew Ning

Faculty Publications

The objective of this research was to develop and compare various airfoil precomputational parameterization and analysis techniques for aerostructural optimization of wind turbine blades. The airfoils along the blade were added as optimization design variables through pre-computational parameterization methods using thickness-to-chord ratios and blended airfoil family factors. The airfoils' aerodynamic performance was analyzed with three methods of increasing fidelity: a panel method (XFOIL), Navier-Stokes based computational fluid dynamics (RANS CFD), and wind tunnel data. The optimizations minimized mass over annual energy production (m/AEP) and thereby approximated the minimization of cost of energy. The results were compared to the NREL 5-MW …

Advanced Technologies For Sustainable Systems, Hesham Safwat

Mechanical Engineering

No abstract provided.