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Motor Output Variability Impairs Driving Ability In Older Adults, Neha Lodha, Hwasil Moon, Changki Kim, Tanya Onushko, Evangelos A. Christou

Biomedical Engineering Faculty Research and Publications

Background: The functional declines with aging relate to deficits in motor control and strength. In this study, we determine whether older adults exhibit impaired driving as a consequence of declines in motor control or strength.

Methods: Young and older adults performed the following tasks: (i) maximum voluntary contractions of ankle dorsiflexion and plantarflexion; (ii) sinusoidal tracking with isolated ankle dorsiflexion; and (iii) a reactive driving task that required responding to unexpected brake lights of the car ahead. We quantified motor control with ankle force variability, gas position variability, and brake force variability. We quantified reactive driving performance with a combination …

Self-Management Of Cognitive Load In Children: Exploring Effective Strategies By Manipulating Informational Text, Marcus J. Hora

Dissertations and Theses @ UNI

This study was designed to measure which reading comprehension strategies were most successful in allowing children to self-manage their cognitive load while reading electronic informational text. It built on previous research on cognitive load theory and teaching children self-management strategies. Participants were sixth grade students in a Midwestern suburban intermediate school.

A quantitative experiment was conducted with a control group and three experimental groups. Experimental groups were taught to highlight key words, draw arrows to show process on a diagram, or move text boxes nearer a corresponding illustration. The control group received equal time with the teacher but did not …

Corn Stover Biochar In Gypsum Board: Empirical Analysis Of Thermal Conductivity And Flexural Strength, Albena Yordanova

Dissertations and Theses @ UNI

Gypsum board, an economical and durable finish material for wall and ceiling construction in the United States and worldwide, is the component with the lowest thermal performance in a typical exterior wall assembly. It also constitutes a substantial portion of construction waste in landfills, potentially creating harmful environmental effects and dangerous gases. To minimize the negative effects of fast growing construction waste of gypsum in landfills and meet higher standards for energy efficiency in construction, there is a need to explore sustainable ways of improving thermal properties of gypsum board and recycling the material. Gypsum can be recycled and used …

Democratizing Startups, Seth C. Oranburg

Scholarly Articles

President Obama signed the Jumpstart Our Business Startups (“JOBS Act”) of 2012 into law to “help entrepreneurs raise the capital they need to put Americans back to work and create an economy that’s built to last.” The goal is to “democratize startups” by making capital available to diverse entrepreneurs in new geographies. Yet the net effect of securities regulations and market conditions is the opposite. Startup companies are encouraged to stay private so capital is consolidating in large, mature firms instead of recycling into new startups. Evidence of consolidation is that once-rare “Unicorns” (billion-dollar startups) now number at least 170. …

Contributions Of Glacier Melting To The Upper Watershed Of The Pita River, Ecuador, Teresa Munoz Martinez

Dissertations, Master's Theses and Master's Reports

Evidence suggests that a changing global climate is accelerating glacial retreat around the world. However, there are not many studies that help to understand the influence of climate change on glaciers in the tropical Andes. In many Andean countries, populations use the water that come from the high altitude mountains, especially mountains that are ice covered. Glacial reduction minimizes water resource availability. This report focuses on better understanding the relationship between glacier meltwater, surface water runoff, and the groundwater flowing into and under the Pita River upper watershed, which crosses the base of the northeast foothills of the Cotopaxi volcano. …

Learning To Notice And Use Student Thinking In Undergraduate Mathematics Courses, Anna Pascoe

Dissertations, Master's Theses and Master's Reports

The goal of this study was to evaluate the outcomes of an intervention focused on developing mathematics graduate teaching assistants’ skills of noticing and effectively responding to instances of student mathematical thinking that have significant potential to further students’ learning. Four mathematics graduate teaching assistants participated in a semester-long intervention in which video of undergraduate mathematics lessons was individually analyzed and then discussed collectively with the researcher on a weekly basis. The MOST Analytic Framework (Leatham, Peterson, Stockero, & Van Zoest, 2015; Stockero, Peterson, Leatham, & Van Zoest, 2014) was introduced as a tool to aid in the analysis and …

Design And Fabrication Of A Suspension Rig, Abhijith Geo Philip

Dissertations, Master's Theses and Master's Reports

Owing to its placement under the vehicle body, the suspension system is one of the parts of the vehicle which are difficult to comprehend completely, albeit being a vital component. For demonstrating the working of a suspension system, a physical model in which one can actually see the movement of all the components would be a great tool. A Mustang II independent front suspension system was purchased from Heidts Engineering Performance and a rig that can emulate some of the real world situations of vehicle suspension action was designed and fabricated. All the components are accessible and conditions like bounce, …

On The Applications Of Interactive Theorem Proving In Computational Sciences And Engineering, Amer Tahat

Dissertations, Master's Theses and Master's Reports

Interactive Theorem Proving (ITP) is one of the most rigorous methods used in

formal verification of computing systems. While ITP provides a high level of confidence in the correctness of the system under verification, it suffers from a steep learning curve and the laborious nature of interaction with a theorem prover. As such, it is desirable to investigate whether ITP can be used in unexplored (but high-impact) domains where other verification methods fail to deliver. To this end, the focus of this dissertation is on two important domains, namely design of parameterized self-stabilizing systems, and mechanical verification of numerical approximations …

Hardware Design And Integration And Software Programming For Optical Elastography, Nima Taherkhani

Dissertations, Master's Theses and Master's Reports

The elastic and viscoelastic properties of skin are a reflection of its health. Measurement of these elastic properties can be used as the indicator of various pathologies. The measurement concept in our works is to mechanically stimulate the skin with a low frequency pneumatic force using non-invasive means of deflecting the skin and use laser speckle to study the elasticity of the skin.

The goal of this work was to develop a setup for in vivo optical elastography of skin. This setup includes an electro-mechanical device which is able to deliver a sinusoidal pneumatic stimulus equivalent to 10 grams of …

Evaluation Of Angular Distribution Of Incident Field At The Transmission Loss Window In Michigan Tech’S Reverberant Chamber, Abhishek Thyagarajan

Dissertations, Master's Theses and Master's Reports

Transmission Loss prediction accuracy is highly dependent on a good understanding of the angular distribution of incident field on the panel. Traditionally, the incident field has been assumed to be either completely random (equal probability of incidence at all angles from 0° - 90°) or field incidence (where the field is assumed to be completely diffuse between 0° - 78°). Studies1-3 have shown that these models are not completely representative of the incident field. This incident field is studied in the Michigan Tech Transmission Loss suite using two different methods in this study; beamforming and acoustic intensity. The beamforming method …

Comparison Of Different Seismic Filtering Techniques On Prestack Inversion For Penobscot Area-Nova Scotia, Omer Emre Uygun

Dissertations, Master's Theses and Master's Reports

The goal of this study is to compare three different type of seismic filtering according to their inversion results and their quality of data improvements. To do this bandpass filter, Inverse Q, and Radon transform are applied to the original NMO corrected pre-stack data from Nova-Scotia offshore Canada.

The seismic data used was provided as pre-stack data of generally good quality. The test for quality of data improvement comes from the results of inversion based on different types of filtering performed on the pre-stack gathers.

Bandpass filter, Inverse Q, and Radon transform are applied to the migrated prestack data, over …

Modeling Spring Catchment Discharge: A Case Study Of Candela, Panama, Central America, Jordan P. Van Sickle

Dissertations, Master's Theses and Master's Reports

Where the proper geological and hydrological conditions exist, natural springs have provided a reliable source of clean water to mankind for eons. Changing climates and land development can negatively impact spring source replenishment and threaten their reliability as a source of water. In the face of prospects of diminishing supplies and increasing population demands, community leaders question whether and how to invest in development for enhancing sustainability and protecting water quality, causing water managers to dispute their reliability given decreasing flows. Springs located in the rugged jungle of western Panama serve as the primary water supply for many indigenous communities, …

Reservoir Estimation In The Penobscot 3d Seismic Volume Using Constrained Sparse Spike Inversion, Offshore Nova Scotia, Canada, Mengchu Xiao

Dissertations, Master's Theses and Master's Reports

The Penobscot study area is located offshore Nova Scotia, Canada. There are two wells, which penetrate the highest potentially commercial bodies in the Abenaki Formation. In order to investigate the potential for locating additional hydrocarbon reservoirs, well log data was used and the Penobscot 3D seismic dataset was analyzed using Constrained Sparse Spike Inversion. From the well log data, low GR and SP values are an indication of a permeable sand layer, which provides the target zone in this study. Impedance – porosity crossplots gave the relationship between impedance and porosity, where a low impedance sand layer is correlated with …

An Analysis Of Stakeholders Communication In Collaborative Software Development Projects, Wei Zhang

Dissertations, Master's Theses and Master's Reports

Software development is a multidisciplinary collaboration involving many stakeholders. However, existing software development processes exhibit many issues related to that collaboration. Because prior research on stakeholder analysis and teamwork revealed the importance of communication, this study analyzed stakeholder communication with reference to team activities as a social and cognitive process. The study’s goal was to understand the collaboration process during software development and to delineate factors that influence this process. We focused on communication between the software developers and their clients during the requirements gathering phase, the team process, and the inter-team and interdisciplinary collaboration, in particular between software engineers …

Wireless Implantable Magnetoelastic Sensors And Actuators For Biomedical Applications, Andrew Derouin

Dissertations, Master's Theses and Master's Reports

Magnetoelastic sensors represent a low-cost wireless and battery-less method for monitoring parameters in embedded or implanted applications; however, some limitations still exist preventing their commercial implementation. Presented in this work are a variety of studies that are aimed at improving the feasibility of magnetoelastic materials for sensing and actuating applications. Magnetoelastic resonant sensors of non-standard geometries were investigated to determine if geometry could play a role on the sensitivity of the sensor response to mass loading. It was shown that a significant increase in sensitivity could be achieved by using triangular sensors rather than standard rectangular strips. A method for …

Experimental Study Of The Flow Of Ferrofluid In A Porous Media Under A Magnetic Field, Muskaan Khurana

Dissertations, Master's Theses and Master's Reports

This research presents results from a laboratory-scale experimental setup that was designed to visualize the behavior of ferrofluid percolation through a porous media. Ferrofluids are colloidal suspensions made of magnetic particles of a few nanometers and stabilized in carrier liquids like water or mineral oil. Ferrofluids get magnetized and align themselves in the direction of a magnetic field when a field gradient is applied.

With the help of this experiment we investigate the viability of controlling fluid flow in porous medium by a magnetic field in vicinity. The experiments show that ferrofluids can be used as a transporting media to …

Energy Justice And U.S. Energy Policy: Case Study Applications Exploring U.S. Energy Policy Through An Energy Justice Framework, Emily Prehoda

Dissertations, Master's Theses and Master's Reports

This thesis presents three examples of U.S. energy policy and demonstrates how these policies violate the principles of energy justice. First, requiring only Federal agencies to obtain a percentage of energy production from renewables violates the distributive energy justice principle through a lack of a federal renewable energy policy which distributes the potential for unequal electrical grid failure to populations. Second, U.S. energy policy violates the procedural energy justice principle through inequitable participation and poor knowledge dissemination that, in some cases, contributes to stagnant renewable targets during the decision-making process and inequitable distribution of the benefits associated with renewable energy …

A Wireless Sensor System With Digitally Controlled Signal Conditioning Circuit For Force Monitoring At Bone Fixation Plates, Govindan Suresh

Dissertations, Master's Theses and Master's Reports

Post-rehabilitation of orthopedic surgery is critical for bone fracture treatments. Current protocols are not based on quantitative assessments of the patient condition but they are conservative estimations mostly based on prior experience and physician’s opinions. While there are quantitative methods for assessing the recovery of orthopedic surgery, they are typically very expensive and provide only snapshots during the healing process. A standalone, reconfigurable, embedded wireless sensor system with digitally controlled signal conditioning system capable of providing continuous monitoring of bone healing is developed. Strain sensor measurements were validated against a commercial mechanical loading instrument for relevant loads that an animal …

Usft 2016-2017 Usf Libraries Annual Report, Usf Libraries

Library Annual Reports

No abstract provided.

Autonomous Dc Microgrid With Self-Configurable Feasibility, Amir Farshad

Dissertations, Master's Theses and Master's Reports

Microgrids are power systems that work not only from the main power grid, but also in island mode operation. As each of the power sources and loads have voltage and current limitations, the autonomous microgrid should be able to control voltage and current levels while loads and sources are connected to the grid. Therefore, the microgrid bus voltage remains constant and power transfers safely.

To configure an autonomous microgrid, the load and source type identification comes to mind. An autonomous microgrid needs to know the type of the electrical components which are going to be connected to the grid. In …

Preliminary Seismic Coda Wave Attenuation Study Of Pacaya Volcano, Guatemala, Maximilian Guettinger

Dissertations, Master's Theses and Master's Reports

Pacaya volcano is a basaltic complex in the Central American Volcanic Arc in Guatemala. Pacaya has been in an open vent condition since 1961. During January 2015 we deployed 19 short period seismometer stations on Pacaya at distances less than 1.5 kilometers from the summit. The resulting data consisted of tremor and thousands of discrete events associated with ongoing outgassing. Where possible, individual events were identified and located. They were found to be high in the edifice near the vent. We used the decaying codas of these events to model the attenuation structure of the Pacaya edifice, following the energy …

High Resolution Time-Of-Arrival Ranging Of Wireless Sensor Nodes In Non-Homogenous Environments, Mohsen Jamalabdollahi

Dissertations, Master's Theses and Master's Reports

Wireless Sensor Networks (WSN) have emerging applications in homogeneous environments such as free space. In addition, WSNs are finding new applications in non-homogeneous (NH) media. All referred applications entail location information of measured data or observed event. Localization in WSNs is considered as the leading remedy, which refers to the procedure of obtaining the sensor nodes relative location utilizing range measurements. Localization via Time-of-Arrival (ToA) estimation has received considerable attention because of high precision and low complexity implementation, however, the traditional techniques are not feasible in NH media due to frequency dispersion of transmitted ranging waveform.

In this work, a …

Finite Element Analysis And Topology Optimization Of Differential Case And Control Arm For Static And Fatigue Loading, Pankaj N. Kalan

Dissertations, Master's Theses and Master's Reports

Optimization of the automobile components can result in a significant decrease in vehicle weight, increase in fuel efficiency and reduction in environmental damage. For example, the lightweight vehicle production will save over 4.4×109 GJ of energy and 4.1×108 tons of CO2 over a 10 year period, compared to the current non-light weight vehicles. This equates to 890 billion miles or 42 billion gallons of gas savings (Wu 2016). This study evaluates the weight reduction possible by using manual and automatic (using Optistruct software) topology optimization processes. Optimization of a vehicle differential case done in this study shows that a weight …

Experimental And Theoretical Investigation Of Sustainable Fast Pyrolysis Biofuels From Woody Biomass, Bethany Jean Klemetsrud

Dissertations, Master's Theses and Master's Reports

Biofuels are an important advancement in alternative energy that can provide substantial environmental benefits compared to their conventional fossil fuel counterparts Said benefits are usually measured using life cycle assessments. However, it is not well understood yet how different methodological choices such as system boundaries, biomass feedstocks, conversion pathways, geographical data, etc. affect the conclusions drawn from biofuels LCA. This research shows large variability in life cycle assessment results and limits comparison across different biofuel pathways due to methodological choices set forth by policy and certification schemes. Advanced biofuels have not reached large scale production due to a limited understanding …

Nonlinear Inversion Strategies Applied To Source Characterization And 3d Earthquake Tomography In Volcanic Environments: A Case Study At Pacaya Volcano, Guatemala, Federica Lanza

Dissertations, Master's Theses and Master's Reports

Full-waveform moment tensor inversion of volcanic seismic signals and travel-time 3D tomography of local earthquakes have been widely used to explore source processes related to magma transport as well as to image the location and size of magma storage systems. However, the inversion solutions and the associated reliability estimates are non-unique and bear intrinsic uncertainties due to simplifying assumptions about the source, inaccuracies in the velocity models, dependence on network configuration, and other a priori constraints imposed by the modeler.

This work addresses the non-uniqueness and uncertainties of the model results by introducing non-linear inversion techniques that allow sampling the …

Objective Bayesian Analysis Of A Generalized Lognormal Distribution, Shengnan Li

Dissertations, Master's Theses and Master's Reports

The generalized lognormal distribution plays an important role in various aspects of life testing experiments. We examine Bayesian analysis of this distribution using objective priors (in the general sense of priors constructed using some formal rules) for the model parameters in this paper. Specifically, the derivation of explicit expressions for multiple types of the Jeffreys priors, the reference priors with different group ordering of the parameters, and the first-order matching priors. We investigate the important issue of proper posterior distributions. It is shown that only two of them lead to proper posterior distributions. Monte Carlo simulations are conducted to compare …

Design And Development Of Optical Elastography Setup, Abhinav Madhavachandran

Dissertations, Master's Theses and Master's Reports

The mechanical properties of the skin are an indication of its physiological condition. The properties can serve as potential information for dermatologists for diagnosis and qualitative assessment. Elastography is a medical imaging modality developed to extract the elastic properties of a tissue by application of an external force. Optical elastography is a technique of elastography which uses laser speckle tracking to study the elastic properties of several soft tissue including skin.

This work is aimed at developing an optical elastography setup that can study the elastic properties of skin. The setup includes an imaging system and a force-application system controlled …

Competition Vehicle Based Intake Manifold Design, Joshua N. Matiash

Dissertations, Master's Theses and Master's Reports

A competitive vehicle in Formula SAE needs to be easy for unskilled drivers to extract the maximum performance from. This requires a predictable and manageable torque curve. This report details the development of an intake manifold for a Formula SAE car from a vehicle-based approach to produce this manageable and predictable torque. The current vehicle was instrumented and driven on a representative track to determine the usage of available torque. Based on these findings an ideal torque curve was chosen that favored increased torque at upper engine speed ranges and decreased torque at lower engine speed ranges. A 1-D engine …

Purification And Recovery Of Infectious Virus Particles Using Osmolyte Flocculation, Ashish Saksule

Dissertations, Master's Theses and Master's Reports

Viral infectious diseases cause millions of deaths and severe illness all around the world affecting public health and economics. Viral vaccines are helping to fight against viral diseases, but current vaccines are expensive and unavailable, especially in poor and developing countries. When measuring the entire manufacturing processing, the downstream processing of vaccines is the major cost of production. Our goal for this research is to develop a low-cost alternative downstream processing platform for new vaccine manufacturing infrastructures. We have developed a novel osmolyte flocculation method for viral particles. To create a platform purification for several types of viral particles, we …

Design Of A Mobile Underwater Charging System, Brian R. Page

Dissertations, Master's Theses and Master's Reports

Autonomous Underwater Vehicles (AUVs) are extremely capable vehicles for numerous ocean related missions. AUVs are energy limited, resulting in short mission endurance on the scale of hours to days. Underwater Gliders (UGs) are able to operate on the order of months to years by using nontraditional propulsion methods. UGs, however, are unable to perform missions requiring high speed or direct forward motion due to the nature of their buoyancy driven motion. This work reviews the current state of the art in recharging AUVs and offers an underwater recharging network concept at a significantly reduced cost to traditional methods. The solution …