Computational Engineering Commons^™

Monte Carlo Simulations Of Photoemission Characteristics From Gaas And Diamond, Abhishek Srivastava

Electrical & Computer Engineering Theses & Dissertations

Monte Carlo based numerical simulations were performed to study photoemission from GaAs and diamond. The central goal was to assess the potential for NEA photoemission from diamond, and to predict its characteristics. The GaAs material system was also included in the simulation study to provide: (i) calibration and validation of the numerical model developed by carefully matching the simulation results with available experimental data, and (ii) quantitative comparisons between the response characteristics of diamond and the better known GaAs system.

Predictions of the energy distribution, temporal response and angular distribution of emitted electrons were obtained. Effects of various parameters, such …

The Crash Simulation And Analysis Of The Friendly Mobile Barrier, Bryan Edward Marz

Mechanical & Aerospace Engineering Theses & Dissertations

Mass transportation is an ever increasing alternative being researched and evaluated in today's society. With the increase of demand for such transportation, an increase in safety is also needed. This research entails the analysis of a new idea, The Friendly Mobile Barrier, in railroad crossing barrier design. The design is meant to prevent any approaching vehicle from crossing a railroad track and be survivable for those impacting the barrier.

Research conducted involves the crash simulation and analysis of the Friendly Mobile Barrier. The Friendly Mobile Barrier was analyzed structurally using finite element analysis. An advanced lumped-mass mathematical model software, Crash …

Parametric Correlations For Generic Scramjet Combustors With Ramp-Type Injectors, Jason Granville Bush

Mechanical & Aerospace Engineering Theses & Dissertations

Development of an efficient scramjet combustor requires the use of computational models due to the cost of full-scale physical testing in the speed regime of Mach 10 through Mach 18. This study focuses upon the database generated by one such computational model, SHIP3D, which describes a generic scramjet combustor using ramp-type file! injectors. Three generalized parametric equations have been developed from this database, which describe the fuel-air mixing efficiency within the scramjet combustor as a function of normalized-axial combustor distance, ramp injector-region lift coefficient, and stoichiometry. It is shown that one of the three equations nearly models the trends as …

Variable Step Size Lms Adaptive Filters With Delayed Coefficient Updating, Guixian Xu

Electrical & Computer Engineering Theses & Dissertations

A new approach to delayed LMS adaptive filtering is presented, which uses a variable step size for coefficient updating to increase convergence speed and improve tracking characteristics. The new algorithm, called delayed variable step size LMS (DVLMS), is explained, analyzed, and simulated to experimentally determine performance characteristics. Three different strategies for adjusting the step size are examined, and their performance is compared. Also, simulation results are presented to show that the proposed DVLMS systems provide faster convergence and lower mis-adjustment than previously proposed DLMS systems.

A Receiving Water Quality Model For Dissolved Metal Runoff From A Floating Drydock, Thomas O. Fenn

Civil & Environmental Engineering Theses & Dissertations

A methodology for modeling the water quality mixing zone of dissolved metal bearing storm water runoff is presented with specific application to floating drydocks in a tidal estuary. The method relies upon a solution of the mass balance equation as contained in the computer program, Water Quality Analysis Simulation Program (WASPS), an Environmental Protection Agency (EPA) model. Separate applications are presented for dissolved metal and solid settling to optimize the WASPS program capabilities.

WASPS provides the capability to evaluate the mass balance equation in a finite difference scheme applied over a large number of small volume segments. The program may …