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

Engineering Commons

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

Articles 1 - 9 of 9

Full-Text Articles in Engineering

Design And Measurement Of Strongarm Comparators, Nathan Robert Whitehead Oct 2019

Design And Measurement Of Strongarm Comparators, Nathan Robert Whitehead

Theses and Dissertations

The StrongARM comparator is utilized in many analog-to-digital converters (ADCs) because of its high power efficiency and rail-to-rail outputs. The performance of the comparator directly affects the speed, power, and accuracy of an ADC. However, the StrongARM comparator performance parameters such as delay, noise, and offset measured directly from silicon prototypes are rare in literature and often consist of small sample sets. In addition, existing techniques to measure the comparator require large chip areas, making it impractical to characterize a large number of comparators to obtain stochastic parameters such as offset and noise. This work presents novel circuit techniques to …


Simulation Of The Inertia Friction Welding Process Using A Subscale Specimen And A Friction Stir Welder, Ty Samual Dansie Apr 2018

Simulation Of The Inertia Friction Welding Process Using A Subscale Specimen And A Friction Stir Welder, Ty Samual Dansie

Theses and Dissertations

This study develops a method to simulate a full-scale inertia friction weld with a sub-scale specimen and modifies a direct drive friction stir welder to perform the welding process. A torque meter is fabricated for the FSW machine to measure weld torque. Machine controls are modified to enable a force control during the IFW process. An equation is created to measure weld upset due to deflection of the FSW machine. Data obtained from a full-scale inertia friction weld are altered to account for the geometrical differences between the sub-scale and full-scale specimens. The IFW are simulated with the sub-scale specimen …


A Model For Analyzing Heating And Cooling Demand For Atria Between Tall Buildings, Samuel David Christensen Jul 2014

A Model For Analyzing Heating And Cooling Demand For Atria Between Tall Buildings, Samuel David Christensen

Theses and Dissertations

The heating and air-conditioning energy demand of skyscrapers with atria between buildings is explored. Radiation, conduction, convection, and ventilation were evaluated to determine annual heating and cooling energy demands for a 100-building city located in Provo, Utah. Spreadsheets models were developed and calibrated with a computational fluid dynamics model. Three spreadsheet model cases were examined: a baseline no-atrium case, a conditioned atrium case, and an unconditioned atrium case. The energy demands and atrium temperatures were compared between the different cases. The research concludes that atria can be used between buildings to reduce the heating and cooling energy demands. The exposed …


A Dynamic Optimization Framework With Model Predictive Control Elements For Long Term Planning Of Capacity Investments In A District Energy System, Jose Luis Mojica Velazquez Dec 2013

A Dynamic Optimization Framework With Model Predictive Control Elements For Long Term Planning Of Capacity Investments In A District Energy System, Jose Luis Mojica Velazquez

Theses and Dissertations

The capacity expansion of a district heating system is studied with the objective of evaluating the investment decision timing and type of capacity expansion. District energy is an energy generation system that provides energy, such as heat and electricity, generated at central locations and distributed to the surrounding area. The study develops an optimization framework to find the optimal investment schedule over a 30 year horizon with the options of investing in traditional heating sources (boilers) or a next-generation combined heat and power (CHP) plant that can provide heat and electricity. In district energy systems, the investment decision on the …


Energy Dissipation Caused By Asphalt Roadway Gouges For Use In Accident Reconstruction, Charles L. Crosby Dec 2009

Energy Dissipation Caused By Asphalt Roadway Gouges For Use In Accident Reconstruction, Charles L. Crosby

Theses and Dissertations

In reconstruction of on-roadway vehicle accidents, roadway surface gouges and the forces and energy attributed to the related vehicle components become important keys to resolving an accurate accident reconstruction. These roadway gouge forces vary depending upon such factors as surface temperature and the velocity and geometry of the gouging mechanism. Accounting for the forces applied to vehicle components and the energy dissipated from such forces can be helpful in accident reconstruction where supporting data exists. This research documents the force necessary to create a given roadway gouge geometry. Controlled pavement gouging tests were performed using roadway surface temperature and gouging …


Soft Surface Roll Mechanics Parameters For Light Vehicle Rollover Accident Reconstruction, Kevin Claude Henry Jul 2007

Soft Surface Roll Mechanics Parameters For Light Vehicle Rollover Accident Reconstruction, Kevin Claude Henry

Theses and Dissertations

Light vehicle rollover accidents on soft surfaces can be modeled assuming constant drag with linear motion equations and other engineering principles. The concept of using segment average results to evaluate roll mechanics parameters throughout a roll sequence, and specifically, segment duration to evaluate vehicle trajectory between ground impacts is developed. The trajectory model is presented, explained and compared to values obtained by analyzing digital video of rollover crash tests. Detailed film analysis procedures are developed to obtain data from rollover crash tests that are not otherwise documented. Elevation of the center of gravity of vehicles is obtained where instrumentation does …


Active Minimization Of Acoustic Energy Density To Attenuate Radiated Noise From A Diesel Generator, Andrew J. Boone Nov 2006

Active Minimization Of Acoustic Energy Density To Attenuate Radiated Noise From A Diesel Generator, Andrew J. Boone

Theses and Dissertations

The focus of this thesis was to use active noise control (ANC) to globally minimize the tonal and broadband noise radiating from a diesel generator enclosure. The major goal of this research was to show that minimizing the noise within the enclosure can lead to an overall sound pressure level (SPL) reduction of radiated noise. The target levels for overall SPL reduction were at least 2 dBA. The control algorithms used in this research were based on a filtered-x LMS adaptive algorithm, which minimizes energy density (ED). Both feedforward and feedback control approaches were investigated. The noise spectrum produced by …


Payback Information: It's Effect On Home Buyers Regarding Energy Efficiency, Steven E. Sparti Jun 2006

Payback Information: It's Effect On Home Buyers Regarding Energy Efficiency, Steven E. Sparti

Theses and Dissertations

This study was conducted to find out how payback analysis would affect consumer decision making with regards to home energy efficient upgrade packages. Three different home plans were obtained from a local builder and seven different energy efficient packages were created. Using Hot2000 the heating and cooling loads were calculated for each building, with each energy efficient package, in each of the four major cardinal directions. The averages were taken and the payback information was calculated. The payback information included the increased cost of the package, the increase in the mortgage payment, the annual savings from heating and cooling bills, …


Development Of Pole Impact Testing At Multiple Vehicle Side Locations As Applied To The Ford Taurus Structural Platform, Mark Halford Warner Nov 2004

Development Of Pole Impact Testing At Multiple Vehicle Side Locations As Applied To The Ford Taurus Structural Platform, Mark Halford Warner

Theses and Dissertations

A test method was developed whereby repeated pole impacts could be performed at multiple locations per test vehicle, allowing a comparison of energy and crush relationships. Testing was performed on vehicles moving laterally into a 12.75 inch diameter rigid pole barrier. Crush energy absorption characteristics at the different locations were analyzed, and the results compared to test data from broad moving barrier crashes and available crash tests with similar pole impacts. The research documents the crush stiffness characteristics for narrow impacts at various points on the side of the Taurus vehicle platform. Factors encountered during the research include the importance …