Physical Sciences and Mathematics Commons^™

Characterization Of Interfacial Interactions By Functionalized Afm Probes, Laura Rickard Dickinson

Dissertations, Theses, and Masters Projects

Interfacial interactions play a crucial role in many complex materials systems, determining many of their properties. However, characterization of these interactions, especially at the micro- to nanometer length scales is experimentally challenging. Consequently, insufficient knowledge of these systems limits technological advances in important applications. In this work, custom functionalized atomic force microscopy (AFM) probes were developed to measure the interaction forces in two important systems: petroleum reservoirs and nanocomposites. Our work seeks a deeper understanding of the specific interactions that occur in these two systems so that modified approaches can be developed to improve them. Petroleum recovery is concerned with …

Understanding Security Threats In Cloud, Zhang Xu

Dissertations, Theses, and Masters Projects

As cloud computing has become a trend in the computing world, understanding its security concerns becomes essential for improving service quality and expanding business scale. This dissertation studies the security issues in a public cloud from three aspects. First, we investigate a new threat called power attack in the cloud. Second, we perform a systematical measurement on the public cloud to understand how cloud vendors react to existing security threats. Finally, we propose a novel technique to perform data reduction on audit data to improve system capacity, and hence helping to enhance security in cloud. In the power attack, we …

Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien

Dissertations, Theses, and Masters Projects

The eastern oyster Crassostrea virginica is an ecologically and commercially important species whose natural populations have been devastated by overharvesting, habitat destruction, and disease, but the rapid growth of oyster aquaculture has shown potential to restore the economic significance of this species. A key threat to the growth and sustainability of oyster aquaculture is the association of human-pathogenic Vibrio bacteria with product marketed for raw consumption. Two Vibrio species, Vibrio vulnificus and Vibrio parahaemolyticus, are the causes of the highest rates of seafood consumption-related mortality and gastrointestinal illness, respectively. Identification of the factors influencing V. vulnificus and V. parahaemolyticus prevalence …

The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje

Dissertations, Theses, and Masters Projects

Thousands of floating objects, known as drifting fish aggregating devices (dFADs), are released every year by commercial tropical tuna purse seine vessels in the three equatorial oceans to aggregate tuna and increase catch. The escalation in the number of dFADs deployed over the last three decades has caused changes in fishing effort that are poorly reflected in traditional indices of purse seine effort and catch per unit of effort (CPUE). In addition, concerns have been raised regarding the impacts of such high numbers of dFADs being deployed on both catch and bycatch species. I studied two aspects of dFAD deployments …

Classification Of Compact 2-Manifolds, George H. Winslow

Theses and Dissertations

It is said that a topologist is a mathematician who can not tell the difference between a doughnut and a coffee cup. The surfaces of the two objects, viewed as topological spaces, are homeomorphic to each other, which is to say that they are topologically equivalent. In this thesis, we acknowledge some of the most well-known examples of surfaces: the sphere, the torus, and the projective plane. We then observe that all surfaces are, in fact, homeomorphic to either the sphere, the torus, a connected sum of tori, a projective plane, or a connected sum of projective planes. Finally, we …

Monte Carlo Approx. Methods For Stochastic Optimization, John Fowler

Pomona Senior Theses

This thesis provides an overview of stochastic optimization (SP) problems and looks at how the Sample Average Approximation (SAA) method is used to solve them. We review several applications of this problem-solving technique that have been published in papers over the last few years. The number and variety of the examples should give an indication of the usefulness of this technique. The examples also provide opportunities to discuss important aspects of SPs and the SAA method including model assumptions, optimality gaps, the use of deterministic methods for finite sample sizes, and the accelerated Benders decomposition algorithm. We also give a …

How Can We Have A Better Public Transportation System? –An Exploratory Agent Based Model, Boyu Liu

Pomona Senior Theses

Public transportation plays an integral part in a city's development, but transportation professionals disagree about whether it is feasible to increase the capacity of public transportation systems at a reasonable cost; and if it is, how. This study develops an agent based model that aims to answer this question and provide a framework to compare the effects of improvements in different aspects of the public transportation service. The results of this study show that it is possible to increase ridership enough to compensate for the increased operational cost, but only in certain circumstances. Interesting phenomenon that might have showed up …

The Development Of Bicyclic Peptide Library Scaffolds And The Discovery Of Biostable Ligands Using Mrna Display, David E. Hacker

Theses and Dissertations

Peptides are a promising class of therapeutic candidates due to their high specificity and affinity for cellular protein targets. However, peptides are susceptible to protease degradation and are typically not cell-permeable. In efforts to design more effective peptide drug discovery systems, investigators have discovered that incorporation of non-canonical amino acids (ncAAs) and macrocyclization overcome these limitations, making peptides more drug-like.

In this work, we exploit the promiscuity of wild-type aminoacyl-tRNA synthetases (aaRSs) to ‘mischarge’ ncAAs onto tRNA and ribosomally incorporate them into peptides using a cell-free translation system. We have demonstrated the ability to incorporate five ncAAs into a single …

Gas-Phase Thermochemical Properties Of Proline-Containing Dipeptides And Fluorinated Alcohols Using The Extended Kinetic Method, Kathy Tang Huynh

Dissertations, Theses, and Masters Projects

No abstract provided.

An Investigation Into Off-Link Ipv6 Host Enumeration Search Methods, Clinton Carpene

Theses: Doctorates and Masters

This research investigated search methods for enumerating networked devices on off-link 64 bit Internet Protocol version 6 (IPv6) subnetworks. IPv6 host enumeration is an emerging research area involving strategies to enable detection of networked devices on IPv6 networks. Host enumeration is an integral component in vulnerability assessments (VAs), and can be used to strengthen the security profile of a system. Recently, host enumeration has been applied to Internet-wide VAs in an effort to detect devices that are vulnerable to specific threats. These host enumeration exercises rely on the fact that the existing Internet Protocol version 4 (IPv4) can be exhaustively …

Lifetime And Efficiency Improvement Of Organic Luminescent Solar Concentrators For Photovoltaic Applications, Yamna El Mouedden

Theses: Doctorates and Masters

In order to achieve the goal of zero net-energy consumption in residential and commercial buildings, substantial research has been devoted to developing methods for energy harvesting from window glass that is capable of passing visible light through the windows of buildings while converting the unwanted invisible solar radiation into electricity. Research has focussed on two particular aspects, namely (i) the integration of thin-film technology for solar radiation transmission control and (ii) light guiding structures for solar radiation routing towards the edges of the glass window.

Recently, photovoltaic (PV) solar cells have been investigated and promoted as products for converting solar …

Predicting The Impact Of Future Climate On Ecologically Important Macroalgae, Charlie Phelps

Theses: Doctorates and Masters

Macroalgae play an important role in coastal reef systems and are often referred to as ecosystem engineers. They serve as primary producers, supporting a diverse range of organisms, and are a sink for atmospheric CO2. Water acidification and ocean warming caused by anthropogenic activities are affecting many marine flora and fauna, potentially impacting the physical and chemical performance of macroalgae and the consumption rates of associated herbivores. Many studies have focused on ocean acidification or ocean warming individually but there is an overall lack of research investigating the combined effects and the ensuing repercussions on consumer-prey relationships.

Three species of …

Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos

Theses: Doctorates and Masters

This biogeographical thesis tests for the presence of taxa-area and distance-decay relationships, which are common among macrobionts, in prokaryotic (bacterial) and micro-eukaryotic (ciliate) communities. Microbial biogeographical patterns may be distinct because of the high abundances, diversity and dispersal capabilities of microbes, in comparison to macrobionts. The Northern Ponds of Lake MacLeod, north-western Australia, provide an ideal location to address this topic, because the ponds are effectively hydrogeomorphologically identical, other than in surface area, and biotic histories can be assumed to differ only according to distance of separation. This means that hypotheses concerning species-sorting and neutral processes on microbial assemblages can …

Influence Of Increased Sediment Exposure On Suspension-Feeder Assemblages In A Temperate Seagrass Meadow, Pierre Bouvais

Theses: Doctorates and Masters

The impact of increased sediment exposure on coastal marine ecosystems is one of the most important contemporary environmental issues. Sediment exposure is defined as the concentrations of sediment particles suspended in the water column and the amount of sediment depositing on the seabed. In addition to natural events, such as land erosion, rainfall, and tidal currents, anthropogenic activities such as land use, road building, logging, mining, port maintenance and dredging, contribute to the discharge of a great amount of sediment in the water column. As sessile suspension-feeder assemblages play a critical role in marine ecosystems through their active transfers of …

Recoverable Resources Calculation Using Non-Linear Methods: A Comparative Study, Matthew Cobb

Theses: Doctorates and Masters

The prediction of recoverable resources at an operating manganese mine is currently undertaken using univariate ordinary kriging of the target variable manganese, and 5 deleterious variables. Input data densities at the time of this calculation are considerably lower than at the time of final selection (grade control), and the potential for unnacceptable conditional bias to be introduced through the use of linear geostatistical methods when determining grade estimates over a small support has led to assessment of the potential benefit of employing the local change of support methods Localised Uniform Conditioning (LUC) and Conditional Simulation (CS). Allowances for the operating …

An Evaluation Of Exposures To Respirable Particulates, Environmental Pm2.5, Pahs And Metal Compounds In Western Australia, Desmond D. Menon

Theses: Doctorates and Masters

It has been well established that air pollution is associated with health impacts. This study investigated the relationship between exposure to air pollutants and potential biomarkers of health effects. The research project was conducted in 2 separate study locations and cohorts.

Study 1: An Evaluation of Children’s Exposures to Respirable Particulates, Environmental PM2.5, PAHs and Metal Compounds in The South West of Western Australia. A cross sectional study to evaluate the exposures of children (n=18), and controls (n=15) to respirable particulates PAHs and metal compounds in the South West of Australia during 2011. Ambient particulate matter (PM2.5) samples were found …

Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion

All Master's Theses

Using mapped paleoshoreline features with high-resolution topographic data and obtained radiocarbon dates on paleoshoreline tufas, I documented precise fault offsets of dated features over the last 25 ka along the Surprise Valley Fault (SVF). Fault offset measured in three lake sections within Surprise Valley ranged from 3.6 m in the southern section to 14.4 m in the central section. The offset paleoshorelines are dated to the late Pleistocene (<22 >ka) and were formed during the latest impoundment of pluvial Lake Surprise since the last glacial maximum. Slip rates vary along strike, assuming a fault dip of 68° with 0.25 ± …

Hazard Identification And Coastal Stratigraphy In Crescent Harbor, Northeast Whidbey Island, Washington, Brian Ostrom

All Master's Theses

Crescent Harbor marsh, on northeastern Whidbey Island, records evidence of co-seismic land-level change 1825 to 1925 cal. yrs. BP. The lithostratigraphy and diatom microfossil assemblages reveal a marsh peat abruptly overlain by intertidal mud, indicating rapid subsidence. Analysis of the modern-day position of depositional facies indicates subsidence from a high marsh to a tidal-flat environment representing an estimated 1.7 m elevation change. The timing of subsidence fits within the dates of a rupture found on the nearby Utsalady Point fault between 1,100 and 2,200 years BP (Johnson et al. 2004). Likely, the stratigraphy at Crescent Harbor records the same event …

Kinetic Decay Of A Polymer/Ink Complex As An O2 Indicator, Becca Hoene

All Master's Theses

Indicator inks are an important part of the continued consumption of packaged goods. This thesis is focused on understanding the kinetics and reaction mechanism for a unique indicator ink that is based upon the oxidation of indigotetrasulfonate (ITS) encapsulated in the polyelectrolyte poly(diallyldimethylammonium chloride) (polyDADMAC). Sodium bisulfite (NaHSO₃) was used as the initial oxygen scavenger and to drive the reduction of the ITS. Studies were predominantly done in solution phase through the dilution of the ink systems. Fluorescence spectroscopy was the primary method used to determine the kinetic decay rates and interaction between the ITS dye molecules and …

Evolution Of A Flood Basalt Crustal Magmatic System: In Situ Mineral Data And Computational Modeling Of The Steens Basalt, Megan Graubard

All Master's Theses

Flood basalts are gigantic basaltic eruptions that modify the mass of the crust via intrusion of mantle-derived magma, and change its composition through interaction between magma and crust. The Steens Basalt, located in southeast Oregon, erupted approximately 16.8 million years ago, and is the oldest member of the Columbia River Basalt Group, the youngest and best-exposed flood basalt province on Earth. The Steens Basalt has an eruption volume of approximately 31,800 km³ and the duration of eruption is estimated to be between ~50,000 and 300,000 years. Major- and trace element whole rock data from 111 stratigraphically controlled samples from …

Gis Data: City Of Chesapeake, Virginia Tidal Marsh Inventory, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Data

The 2016 Tidal Marsh Inventory update for City of Chesapeake, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.

Gis Data: City Of Chesapeake, Virginia Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon A. Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen A. Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Data

The 2016 Inventory for City of Chesapeake was generated using on-screen, digitizing techniques in ArcGIS® - ArcMap v10.2.2 while viewing conditions observed in Bing high resolution oblique imagery, Google Earth, and 2013 imagery from the Virginia Base Mapping Program (VBMP). Four GIS shapefiles are developed. The first describes land use and bank conditions (Chesapeake_lubc_2016). The second portrays the presence of beaches (Chesapeake_beaches_2016). The third reports shoreline structures that are described as arcs or lines (e.g. riprap) (Chesapeake_sstru_2016). The final shapefile includes all structures that are represented as points (e.g. piers) (Chesapeake_astru_2016). The metadata file accompanies the shapefiles and defines attribute …

Sea Level Acceleration In The China Seas, Yongcun Cheng, Tal Ezer, Benjamin D. Hamlington

CCPO Publications

While global mean sea level rise (SLR) and acceleration (SLA) are indicators of climate change and are informative regarding the current state of the climate, assessments of regional and local SLR are essential for policy makers responding to, and preparing for, changes in sea level. In this work, three acceleration detection techniques are used to demonstrate the robust SLA in the China Seas. Interannual to multidecadal sea level variations (periods >2 years), which are mainly related to natural internal climate variability and significantly affect estimation of sea level acceleration, are removed with empirical mode decomposition (EMD) analysis prior to the …

Gis Data: Prince George County And The City Of Hopewell, Virginia Shoreline Management Model, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring, Jessica Hendricks, David Weiss, Carl Hershner

Data

The Shoreline Management Model is a GIS spatial model that determines appropriate shoreline best management practices using available spatial data and decision tree logic. Available shoreline conditions used in the model include the presence or absence of tidal marshes, beaches, and forested riparian buffers, bank vegetation cover, bank height, wave exposure (fetch), nearshore water depth, and proximity of coastal development to the shoreline. The model output for shoreline best management practices is displayed in the locality Comprehensive Map Viewer. One GIS shapefile is developed that describes two arcs or lines representing practices in the upland area and practices at the …

Are Long Tide Gauge Records In The Wrong Place To Measure Global Mean Sea Level Rise?, P. R. Thompson, B. D. Hamlington, F. W. Landerer, S. Adhikari

CCPO Publications

Ocean dynamics, land motion, and changes in Earth's gravitational and rotational fields cause local sea level change to deviate from the rate of global mean sea level rise. Here we use observations and simulations of spatial structure in sea level change to estimate the likelihood that these processes cause sea level trends in the longest and highest-quality tide gauge records to be systematically biased relative to the true global mean rate. The analyzed records have an average twentieth century rate of approximately 1.6 mm/yr, but based on the locations of these gauges, we show that the simple average underestimates the …

Developing Priority Variables (“Ecosystem Essential Ocean Variables” — Eeovs) For Observing Dynamics And Change In Southern Ocean Ecosystems, Andrew J. Constable, Daniel P. Costa, Oscar Schofield, Louise Newman, Edward R. Urban Jr., Elizabeth A. Fulton, Jessica Melbourne-Thomas, Tosca Ballerini, Philip W. Boyd, Angelika Brandt, Eileen E. Hofmann

CCPO Publications

Reliable statements about variability and change in marine ecosystems and their underlying causes are needed to report on their status and to guide management. Here we use the Framework on Ocean Observing (FOO) to begin developing ecosystem Essential Ocean Variables (eEOVs) for the Southern Ocean Observing System (SOOS). An eEOV is a defined biological or ecological quantity, which is derived from field observations, and which contributes significantly to assessments of Southern Ocean ecosystems. Here, assessments are concerned with estimating status and trends in ecosystem properties, attribution of trends to causes, and predicting future trajectories. eEOVs should be feasible to collect …

Modeling Ice Shelf/Ocean Interaction In Antarctica: A Review, Michael S. Dinniman, Xylar S. Asay-Davis, Benjamin K. Galton-Fenzi, Paul R. Holland, Adrian Jenkins, Ralph Timmerman

CCPO Publications

The most rapid loss of ice from the Antarctic Ice Sheet is observed where ice streams flow into the ocean and begin to float, forming the great Antarctic ice shelves that surround much of the continent. Because these ice shelves are floating, their thinning does not greatly influence sea level. However, they also buttress the ice streams draining the ice sheet, and so ice shelf changes do significantly influence sea level by altering the discharge of grounded ice. Currently, the most significant loss of mass from the ice shelves is from melting at the base (although iceberg calving is a …

Modelling The Response Of Ice Shelf Basal Melting To Different Ocean Cavity Environmental Regimes, David E. Gwyther, Eva A. Cougnon, Benjamin K. Galton-Fenzi, Jason L. Roberts, John R. Hunter, Michael S. Dinniman

CCPO Publications

We present simulation results from a version of the Regional Ocean Modeling System modified for ice shelf/ocean interaction, including the parameterisation of basal melting by molecular diffusion alone. Simulations investigate the differences in melting for an idealised ice shelf experiencing a range of cold to hot ocean cavity conditions. Both the pattern of melt and the location of maximum melt shift due to changes in the buoyancy-driven circulation, in a different way to previous studies. Tidal forcing increases both the circulation strength and melting, with the strongest impact on the cold cavity case. Our results highlight the importance of including …

Simulation Of Nuclear Fusion Using A One Dimensional Particle In Cell Method, Steven T. Margell

Cal Poly Humboldt theses and projects

In this thesis several novel techniques are developed to simulate fusion events in an isotropic, electrostatic three-dimensional Deuterium-Tritium plasma. These techniques allow us to accurately predict three-dimensional collision events with a one-dimensional model while simultaneously reducing compute time via a nearest neighbor algorithm. Furthermore, a fusion model based on first principles is developed that yields an average fusion reactivity which correlates well with empirical results.

The Status Of Virginia's Public Oyster Resource 2015, Melissa Southworth, Roger L. Mann

Reports

This report summarizes data collected during 2015 in the Virginia portion of the Chesapeake Bay. The report is composed of two parts, part one, oyster recruitment (shell string) in Virginia and part two, dredge survey of selected oyster bars in Virginia.