Physical Sciences and Mathematics Commons^™

Metalloporphyrin-Catalyzed Reduction Reactions Of Hexavalent Chromium, Rong Zhang

All Theses

Previous studies have demonstrated that the reduction of oxidized organic and inorganic contaminants could be catalyzed by electron shuttle systems, which generally were biological organic macrocycle complexes with transition metals. Metalloporphyrins (MPs) and their derivatives are well known electron shuttles for many biogeochemical systems. The objective of this research was to study the catalytic capabilities of selected MPs for the reduction of hexavalent chromium (Cr(VI)) in the presence of reducing agents. Zero valent iron (ZVI) was chosen as the primary electron donor in the experimental systems. Protoporphyrin IX (Proto) and Uroporphyrin I (Uro) are naturally occurring porphyrins produced during heme …

Factors Influencing The Adsorption Of Synthetic Organic Compounds By Carbon Nanotubes In Aquatic Environments, Ting Shao

All Theses

Carbon nanotubes (CNTs) are allotropes of carbon consisting of sheets of carbon atoms covalently bonded in hexagonal arrays that are seamlessly rolled into a hollow, cy-lindrical shape with both ends rounded by fullerene-like caps. As large amounts of CNTs have been manufactured and significant growth is expected in commercial CNT produc-tion, there is a major concern over their health and environmental risks once they enter into the environment. In aquatic systems, CNTs are likely to adsorb organic chemicals and aggregate as bundles due to their extremely hydrophobic surfaces. The aggregation state of CNTs plays a significant role in their fate …

A Verifying Compiler For Embedded Networked Systems, Kalyan Chakradhar Regula

All Theses

Embedded networked devices are required to produce dependable outputs and communicate with peer devices given limited computing resources. These devices monitor and control processes within the physical world. They are used in applications related to environmental monitoring, telecommunications, social networking, and also life-critical applications in domains such as health care, aeronautics, and automotive manufacturing. For such applications, software errors can be costly - both in terms of nancial and human costs. Therefore, software programs installed on these devices must meet the appropriate requirements. To guarantee this, one must verify that the implemented code meets the corresponding specications. Manual trial-and-error validation …

Multiple Criteria Decision Analysis For The Selection Of A Land Use Impact Method For A Life Cycle Assessment Of Switchgrass As A Bioenergy Feedstock In The Pee Dee Region Of South Carolina, Joel Kohn

All Theses

The interactions of a growing human population and increasing demand for food and energy have led to governmental and social pressures encouraging the adoption of biofuels as a substitute for fossil energy sources; however, several potential biofuel feedstocks can compete directly with food products for valuable land area. Life Cycle Assessment (LCA) is a tool that examines the environmental impacts of a product or process and can assist decision makers in the development of policy. The environmental impacts of land use are not well incorporated into LCA. As an emerging field, there is no consensus regarding the best methods by …

Developing A Management Tool To Estimate Unmarked Puma (Puma Concolor) Populations With A Remote Camera Array, Megan Pitman

All Theses

Puma (Puma concolor) ecological research, puma management, and puma conservation require a technique to efficiently estimate puma populations. Adequate population estimates for pumas are difficult to produce due to natural history characteristics of the species. Remote camera arrays present a promising new tool for surveying cryptic mammals, but techniques for estimating population levels of unmarked animals or species that are difficult to individually identify in photographs are needed. Our goal was to develop techniques to (1) determine the camera effort needed to detect resident pumas with 95% certainty and (2) estimate puma population density for unmarked pumas with a remote …

Contaminant Flow And Transport Simulation In Cracked Porous Media Using Locally Conservative Schemes, Pu Song

All Theses

The purpose of this paper is to analyze some features of contaminant flow passing through cracked porous media, such as the influence of fracture network on the advection and diffusion of contaminant species, the adsorption impact of contaminant wastes on the overall transport flow and so on. In order to precisely describe the whole process, we firstly need to build the mathematical model to simulate this problem numerically. Taking into consideration of the characteristics of contaminant flow, we employ two partial differential equations to formulate the whole problem. One is flow equation, the other is reactive transport equation. The first …

Numerical Modeling Of Contaminant Transport In Fractured Porous Media Using Mixed Finite Element And Finite Volume Methods, Chen Dong

All Theses

A mathematical model for contaminant species passing through fractured porous media is presented. In the numerical model, we combine two locally conservative methods, i.e. mixed finite element (MFE) and the finite volume methods. Adaptive triangle mesh is used for effective treatment of the fractures. A hybrid MFE method is employed to provide an accurate approximation of velocities field for both the fractures and matrix which are crucial to the convection part of the transport equation. The finite volume method and the standard MFE method are used to approximate the convection and dispersion terms respectively. Numerical examples in different fractured media …

Behavioral Animation For Maya Particles Using Steering Forces, Edgar Rodriguez

All Theses

Maya has various built-in solutions for modeling effects. Maya does not, however, offer a built-in solution for modeling so called 'steering behaviors.' While users may rely on particle expressions or scene rigs, these solutions are generally time consuming and ultimately limiting in their cross application. Accordingly, Maya's particle system was extended, by implementing a new force, which can be used to model a set of steering behaviors. The new force was coded in Python and was implemented using Maya's Python Application Programming Interface ('API'). The new force can be used in conjunction with the particle system's existing forces and Maya's …

Predicting Long-Term Well Performance From Short-Term Well Tests In The Piedmont, David Hisz

All Theses

A reliable estimate of the physically sustainable discharge of a well is a fundamental aspect affecting management of water resources, but there are surprisingly few analyses describing on how to make such an estimate. Current available methods include either an empirical or a quantitative approach. The empirical method is based on holding the head or flow rate constant in order to maintain a target drawdown for as long as possible. The second method involves conducting a constant rate test to calculate the properties of the aquifer, T and S, and extrapolate the drawdown using a type curve (i.e. Theis analysis). …

Creating Touchpanel Graphics For Control Systems, Lucas Mcdaniel

All Theses

More often than system designers would like to admit, a discrepancy lies between the implementation of audiovisual control systems and their apparent ease of use to a novice or casual user. System designers and programmers are often hampered by the software tools provided by industry manufacturers and cannot reliably create desirable graphical interfaces that match the level of systems they are asked to program and install.
Popular consumer trends in portable touchscreen devices, pioneered on devices such as the Apple iPhone, light a way forward into a new era of elegantly solving the audiovisual control system graphical user interface problem. …

Isotropic And Anisotropic Metallic And Bimetallic Nanoparticles And Their Potential Applications In Biology, Minghong Liu

Dissertations

The development of synthetic procedures that produce nanoscale materials with controlled morphology is a significant area of investigation in nanotechnology. We have developed new synthetic procedures for fabrication of isotropic and/or anisotropic nanomaterials composed of palladium, ruthenium, nickel and alloys of palladium-ruthenium. The nanomaterials were fully characterized and were found to display unique size dependent properties. The electrochemical properties of isotropic palladium, ruthenium and palladium-ruthenium nanoparticles were investigated and the results showed that the particles were capable of charge storage and charge transfer on demand. Anisotropic palladium, ruthenium and palladium ruthenium nanoparticles were also fabricated and fully characterized. The nanoparticles …

Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte

Dissertations

The current study entails the construction of a novel nano-composite catalyst based on ZnO and Au nanoparticles and demonstrates its distinctive photocatalytic characteristics. Monodisperse gold nanoparticles (GNPs) passivated with monolayers of tiopronin or glutathione were synthesized via facile methods, and they were assembled on ZnO nanoparticles to form the nanocatalyst.

Steady state and time resolved photoluminescent studies on the nanocomposite revealed interesting charge transfer characteristics within the nanocomposite. Enhanced photooxidation of rhodamine 6G was observed for the nano-composite over bare ZnO, and modulation of photoactivity with the extent of GNP loading was illustrated. Photoreduction of thionine over the nanocomposite was …

Messaging Behavior Modeling In Mobile Social Networks, Byung-Won On, Ee Peng Lim, Jing Jiang, Freddy Tat Chua Chua, Viet-An Nguyen, Loo Nin Teow

Research Collection School Of Computing and Information Systems

Mobile social networks are gaining popularity with the pervasive use of mobile phones and other handheld devices. In these networks, users maintain friendship links, exchange short messages and share content with one another. In this paper, we study the user behaviors in mobile messaging and friendship linking using the data collected from a large mobile social network service known as myGamma (m.mygamma.com). We distinguish two types of user behaviors: soliciting active responses for an initiated message and responding to an incoming message. We propose various models for the two behaviors also known as engagingness and responsiveness. Our experiments show that …

A Hubel Wiesel Model For Hierarchical Representation Of Concepts In Textual Documents, Kiruthika Ramanathan, Luping Shi, Chong Chong Tow

Research Collection School Of Computing and Information Systems

Hubel Weisel models of the cortex describe visual processing as a hierarchy of increasingly sophisticated representations. While several models exist for image processing, little work has been done with Hubel Weisel models out of the domain of object recognition. In this paper, we describe how such models can be extended to the representation of concepts, resulting in a model that shares several properties with the PDP model of semantic cognition. The model that we propose is also capable of incremental learning, in which the knowledge is stored in the strength of the neuron connections. Degradation of old knowledge occurs as …

Cloud Services From A Consumer Perspective, Philip Koehler, Arun Anandasivam, Dan Ma

Research Collection School Of Computing and Information Systems

Although there is an increased attention on Cloud Computing in the academic literature in the recent years, most research work focus on technical aspects of cloud computing. Research on consumers’ preferences for cloud services is limited to studies from consulting and industry companies. This paper fills the gap by empirically identifying consumer preferences for cloud service attributes. Using conjoint methods we reveal the relative importance of different attributes of cloud services. The results help both practitioners and academic researchers to better understand the prerequisites of a successful market introduction of cloud services and to design appropriate services. Moreover, the derived …

On The Annotation Of Web Videos By Efficient Near-Duplicate Search, Wan-Lei Zhao, Xiao Wu, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

With the proliferation of Web 2.0 applications, usersupplied social tags are commonly available in social media as a means to bridge the semantic gap. On the other hand, the explosive expansion of social web makes an overwhelming number of web videos available, among which there exists a large number of near-duplicate videos. In this paper, we investigate techniques which allow effective annotation of web videos from a data-driven perspective. A novel classifier-free video annotation framework is proposed by first retrieving visual duplicates and then suggesting representative tags. The significance of this paper lies in the addressing of two timely issues …

Decentralized Resource Allocation And Scheduling Via Walrasian Auctions With Negotiable Agents, Huaxing Chen, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

This paper is concerned with solving decentralized resource allocation and scheduling problems via auctions with negotiable agents by allowing agents to switch their bid generation strategies within the auction process, such that a better system wide performance is achieved on average as compared to the conventional walrasian auction running with agents of fixed bid generation strategy. We propose a negotiation mechanism embedded in auctioneer to solicit bidders’ change of strategies in the process of auction. Finally we benchmark our approach against conventional auctions subject to the real-time large-scale dynamic resource coordination problem to demonstrate the effectiveness of our approach.

Hoare Logic For Graph Programs, Christopher M. Poskitt, Detlef Plump

Research Collection School Of Computing and Information Systems

We present a new approach for verifying programs written in GP (for Graph Programs), an experimental programming language for performing computations on graphs at a high level of abstraction. Taking a labelled graph as input, a graph program nondeterministically applies to it a number of graph transformation rules, directed by simple control constructs such as sequential composition and as-long-as-possible iteration. We adapt classical Hoare logic to the domain of graphs, and describe a system of sound proof rules for showing the partial correctness of graph programs.

Synthesis And Characterization Of Photoactive Amorphous Molecular And Polymeric Pyridinium Materials, Alexi Kamenov Nedeltchev

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pyridinium materials both molecular and polymeric are interesting class of multifunctional electrolytes and polyelectrolytes, which exhibit liquid-crystalline and light-emitting properties. Moreover, their properties could be easily tuned simply by modifying the chemical structures of counterions.

In this dissertation, we described the preparation and analysis of new ionic molecular materials based on bis(pyridinium salt)s and a new class of poly(pyridinium salt)s with various heterocyclic moieties in their backbones with various organic counterions. They were prepared by either ring-transmutation reaction or by metathesis reaction. Their chemical structures were confirmed by FTIR, 1H and 13C NMR spectroscopy and elemental analysis. They had excellent …

Vibrational Spectroscopic Study Of The 1,3,5,7-Cyclooctatetraene At High Static Pressures, Edward Romano

UNLV Theses, Dissertations, Professional Papers, and Capstones

1,3,5,7-cyclooctatetraene (COT) is a single-ringed hydrocarbon that has not been studied extensively under high static pressures. It was the intent of this study to reveal its high-pressure behavior through its vibrational spectra. To this end, its infrared spectra as a function of pressure were collected at the National Synchrotron Light Source (NSLS) U2A beamline, as well as its Raman spectra over pressure using a micro-Raman spectrometer.

The spectra show the typical stiffening of force constants with increasing pressure for most peaks, particularly those which would theoretically exhibit a mode-softening behavior under hypotheses of molecular planarization and aromatization. Additionally, the data …

Conservation Based Uncertainty Propagation In Dynamic Systems, Lillian J. Ratliff

UNLV Theses, Dissertations, Professional Papers, and Capstones

Uncertainty is present in our everyday decision making process as well as our understanding of the structure of the universe. As a result an intense and mathematically rigorous study of how uncertainty propagates in the dynamic systems present in our lives is warranted and arguably necessary. In this thesis we examine existing methods for uncertainty propagation in dynamic systems and present the results of a literature survey that justifies the development of a conservation based method of uncertainty propagation. Conservation methods are physics based and physics drives our understanding of the physical world. Thus, it makes perfect sense to formulate …

Neutron Flux And Energy Characterization Of A Plutonium-Beryllium Isotopic Neutron Source By Monte Carlo Simulation With Verification By Neutron Activation Analysis, Zachary R. Harvey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to characterize the neutron energy distribution and flux emitted from the UNLV plutonium-beryllium source, serial number MRC-N-W PuBe 453. This was accomplished through the use of the MCNPX/5 Monte-Carlo particle transport code to simulate radiation interactions within the physical environment of the source and its surroundings. The moderating drum currently containing the source as well as all of the sampling ports were accurately modeled in MCNPX/5. This geometry was then used to simulate the neutron interactions taking place in these geometries. The results of the simulations were then verified by the use of specifically …

Arima Model For Forecasting Poisson Data: Application To Long-Term Earthquake Predictions, Wangdong Fu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Earthquakes that occurred worldwide during the period of 1896 to 2009 with magnitude greater than or equal to 8.0 on the Richter scale are assumed to follow a Poisson process. Autoregressive Integrated Moving Average models are presented to fit the empirical recurrence rates, and to predict future large earthquakes. We show valuable modeling and computational techniques for the point processes and time series data. Specifically, for the proposed methodology, we address the following areas: data management and graphic presentation, model fitting and selection, model validation, model and data sensitivity analysis, and forecasting.

Wind Flow Modeling For Wind Energy Analysis Of The Nellis Dunes Area In Nevada, Upendra Rangegowda

UNLV Theses, Dissertations, Professional Papers, and Capstones

A wind energy analysis of the Nellis Dunes area in Nevada was conducted. A DEM file which contains the elevation data was used to generate the surface model and to create a 3-D mesh of the region. Local meteorological tower data collected for a period of one year was used to generate the diagnostic initial wind fields. Upper level wind fields were created using a surface boundary layer technique along with linear interpolation of the tower level wind fields. The vertical components of the velocities were adjusted using the equation of continuity. Mass consistent 3-D wind fields were then calculated …

Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird

UNLV Theses, Dissertations, Professional Papers, and Capstones

At a native stand of creosote bush (Larrea tridentata) in North Las Vegas, a rainfall simulation study was conducted over a 12 month period from October 2005 to October 2006. Simulated rainfall occurred during the winter, spring, summer, and fall periods. Rainfall simulation systems were positioned on each of 12 plots, each containing a single creosote bush. Simulated rainfall events occurred at night with multiple short pulses designed to maximize infiltration while minimizing ponding. Yearly simulated rainfall amounts were set at 0, 15, 30 and 60 cm (replicated three times) and were approximately 0, 1.5, 3.0 and 6.0 times the …

The Relationships Of Streambank Angles And Shapes To Streambank Erosion Rates In The Little River Watershed, Tn, William Ryan Foster

Masters Theses

Sediment is a leading cause of water quality impairment throughout the United States. In the Little River watershed in eastern Tennessee, several tributaries have been classified as impaired due primarily to sedimentation. Researchers at The University of Tennessee, in collaboration with a group of local and state organizations, began monitoring Little River tributaries to better understand their sources of pollution. To investigate the rates and processes of streambank erosion, erosion-pin monitoring sites were established on 32 banks in the watershed. This thesis complements the erosion-pin monitoring efforts by determining bank characteristics and examining the relationships of streambank angles and shapes …

Determining The Activity Of Three Hdac Variants In The Presence Of Compounds Containing 1,2,3-And 1,2,4-Triazoles As Zinc Binding Groups, Rachel Louise Glazener

Masters Theses

Histone Deacetylase (HDAC) plays a vital role in cellular processes, for example gene expression, cell growth, and apoptosis. Finding drug candidates to inhibit the over activity of HDACs in cancer is a growing area of interest. Inhibitors, thus far, have three important motifs to be studied: the zinc binding group, a hydrophobic linker, and a cap group. By altering these groups on the inhibitor, not only can activity be increased but also selectivity within the classes of HDACs. We present the design of two novel sets of molecules that contain either a 1,2,3-triazole or 1,2,4-triazole. The 1,2,3-triazoles were synthesized using …

An Investigation For The Need Of Secondary Treatment Of Residential Wastewater When Applied With A Subsurface Drip Irrigation System, Boone S. Hillenbrand

Masters Theses

The objective of this study was to investigate the need for domestic wastewater to receive secondary treatment when being applied to the soil by subsurface drip irrigation (SDI). SDI uniformly distributes wastewater into the soil, which optimizes the soil’s chemical, physical, and biological capacity to remove waste constituents. Because of these advantages, many regulatory jurisdictions are allowing SDI at sites that previously were prohibited from using conventional trench-based soil application systems because of shallow soil restrictions. However, most of these regulatory agencies also require that the wastewater receives secondary treatment (dissolved organic carbon reduction) before the SDI system. At issue …

Simultaneous Seismic Imaging And Inversion Using An Inverse Scattering Algorithm For One Dimensional Media, Ashley Ciesla

Theses, Dissertations and Culminating Projects

The goal of this thesis is to test the capability and efficiency of an inverse scattering algorithm for imaging seismic data. The algorithm we are investigating simultaneously images and inverts one-dimensional, one-parameter (velocity), acoustic reflection data. The algorithm does not require a velocity model or any other a priori information about the medium under investigation, the only input being a reference velocity (the speed of sound in water) and the data collected in the experiment. We assume that the data contains no source wavelet and all other events except primary reflections have been removed in preprocessing. We simulate two types …

Petrology And Geochemistry Of The Pompton Pink Granite, New Jersey Highlands, Ian Phillip Johnson

Theses, Dissertations and Culminating Projects

The Pompton Pink Granite is a small (~1 km²), post-orogenic granitoid body located in the New Jersey Highlands. It is a mildly peraluminous (ASI or aluminum saturation index, A/CNK = molar Al₂O₃ / (CaO + Na₂O + K₂O) > 1.0) pluton composed of microcline, microperthite, quartz, oligoclase, epidote, biotite, and magnetite and is classified as a granite based on its mineral and geochemical composition using standard IUGS classification schemes. The Pompton Pink Granite shows similar major-element geochemistry to other A-type granitoids found in the New Jersey Highlands, but its trace­ element geochemistry distinguishes it from these other …