Physical Sciences and Mathematics Commons^™

An Ab-Initio Study Of The Elastic Properties Of Important Group Iv Diborides At High Temperatures, Manny Gonzales

Open Access Theses & Dissertations

Presented is an ab-initio Molecular Dynamics (MD) study, employing the Density Functional Theory (DFT), of the lattice parameter, thermal expansion coefficients and elastic constants of ZrB₂, TiB₂ and HfB₂ as a function of temperature. The MD trajectories provide the equilibrium lattice parameters at finite temperatures, and the gradient of the energy from these equilibrium solutions is then used to calculate the components of the stiffness tensor. The results for ZrB₂ are shown to agree well with reported experimental results for the lattice parameters and elastic constants as a function of temperature.

Transfer Learning Techniques For Deep Neural Nets, Steven M. Gutstein

Open Access Theses & Dissertations

Inductive learners seek meaningful features within raw input. Their purpose is to accurately categorize, explain or extrapolate from this input. Relevant features for one task are frequently relevant for related tasks. Reuse of previously learned data features to help master new tasks is known as &lsquo transfer learning &rsquo. People use this technique to learn more quickly and easily. However, machine learning tends to occur from scratch.

In this thesis, two machine learning techniques are developed, that use transfer learning to achieve significant accuracy for recognition tasks with extremely small training sets and, occasionally, no task specific training. These methods …

Physical And Biochemical Assessment Of Mexican Palo Verde Response To Chromium Toxicity, Yong Zhao

Open Access Theses & Dissertations

In the United States, about 1/3 of the 1400 superfund sites have been reported to be chromium contaminated, making chromium the second most common metal found in superfund chemical contamination sites. Chromium removal from soil has commonly been carried out via chemical, physical, and thermal processes. However, these methods are expensive and/or invasive to local ecosystems. In contrast to these techniques, phytoremediation (the use of plants to remove toxic substances from areas containing contamination at low or medium levels) appears to be a cost-effective and environmentally friendly process for chromium removal. However, most reports on chromium phytoremediation suggest that this …

Enthalpies Of Mixing Of Water And Alkoxyethanols, John Enriquez

Open Access Theses & Dissertations

Alkoxyethanols [C_mH_2m+1·(OC₂H₄)·OH] (conveniently abbreviated to C_mE₁) are a subgroup of the alkyl poly(ethylene glycol) mono-ethers. They are small relatives of a large number of non-ionic detergents. The thermodynamic properties of their mixing in water have been shown to be good sources of information about the interactions of both hydrophilic and hydrophobic groups with water. Theses alkoxyethanols, or glycol ethers, are the ether derivatives of ethylene glycol where one hydroxyl functional group is substituted for an alkoxy functional group. Our group has already published results for aqueous excess properties …

Investigations Of Grade Control, Macarthur Mine, Yerington, Nevada: An Oxidized Porphyry Copper System, Joseph Daniel Louis Lori

Open Access Theses & Dissertations

Supergene enriched, low-grade oxidized porphyry copper deposits are of great economic value. Oxidized porphyry sections are economic targets because even low-grade prospects have the potential to produce low-cost copper in an environmentally friendly fashion due to easy leachability and high recovery rates of the oxide mineralization. The MacArthur Mine, in the historic Yerington mining district of Nevada, is the focus of this study. The MacArthur is a tilted oxidized porphyry deposit, partially mined by open pit methods, hosted in the Jurassic Bear Quartz Monzonite of the Yerington batholith. The objective of the study is to define controls of copper oxide …

A Gis-Based Emission And Air Quality Impact Assessment For Evaluating Transportation Mitigation Measures, Jose Maria Mares

Open Access Theses & Dissertations

The research presented here develops a framework that assesses a transportation project's air quality impact. The framework not only integrates transportation and emission modeling but also improves the accuracy of the emission estimates. In order to do this, the framework makes use of six modules: environmental conditions data input, GIS database, emission modeling, transportation network, post-processing, and graphical presentation. Each module aims to improve the quality and accuracy of the inputs used by MOBILE6.2. In addition, the framework has the capability, among other features, of presenting the emission estimates in a GIS-based modeling platform that enables the analyst to spatially …