Physical Sciences and Mathematics Commons^™

Relationship Between Log Permeability And Fraction Of Finer Grains In Bimodal Sediment Mixtures, Steven M. Verdibello

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In sediment mixtures of two grain-size components, the mixture porosity (Φ) and permeability (k) both vary non-linearly as a function of the grain size and the volume fraction of each component. A porosity minimum (Φmin) occurs near the mixture fraction at which the volume of the finer grains equals the original pore volume of the coarser grains. An abrupt change in slope has been observed in the non-linear relationship between log(k) and the volume fraction of finer grains (rf). This slope change should occur at the rf where coarser pore pathways change from continuous to discontinuous. In this study, fine …

The Influence Of Streambed Heterogeneity On Hyporheic Exchange In Gravelly Rivers, Yaoquan Zhou

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Hyporheic exchange can be influenced by channel meanders, by streambed topography, and by the heterogeneity within subsurface sediments. Fluvial systems with streambed sediments composed of sandy gravel can be heterogeneous and contain open-framework gravel stratasets that comprise roughly one-third of the sedimentary deposit by volume. The open-framework gravel stratasets have an average lateral length scale on the order of 10 m, average thickness on the order of a decimeter, and an average dip on the order of 10 degrees downstream. The hydraulic conductivity of open-framework gravel stratasets is on the order of 10-1 m/s, and for the larger volume of …

A Hardware Compact Genetic Algorithm For Hover Improvement In An Insect-Scale Flapping-Wing Micro Air Vehicle, Kathleen M. Timmerman

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Wing and airframe damage to insect scale micro air vehicles potentially cause significant losses in pose and position control precision. Although one can imagine many possible means of adapting the flight controllers to restore precise pose and position control, severe limits on computational resources available on-board an insect sized vehicle render many of them impractical. Additionally, limits on sensory capability degrade any such vehicle's ability to critique its own performance. Any adaptive solutions one would propose to recover flight trajectory precision, therefore, would require a resource light implementation, preferably without need for relatively expensive floating-point operations, along with the capability …

Among-Locus Heterogeneity In Genetic Diversity And Divergence In Two Pairs Of Duck Species (Genus: Anas), Kirandeep K. Dhami

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Genetic diversity and divergence at a locus are the result of interactions among the fundamental evolutionary forces of mutation, genetic drift, gene flow and natural selection. Variation in the strength of these forces can cause high heterogeneity in diversity and divergence across the genome. The overall objective of this thesis was to examine the role of population history vs. selection in generating heterogeneity in genetic diversity and differentiation. In Chapter 1, I examine the role of dispersal behavior in causing genetic differentiation and population structure within and between two morphologically distinct Australian duck species that differ in ecology and life …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Factors Controlling Nickel Bioavailability And Effects On Benthic Invertebrates In Hardwater Freshwater Streams, Kevin Wayne Custer

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Sediments in aquatic ecosystems function ecologically as habitat, food, and refugia that aid in reproduction processes, and chemically as sources and sinks for contaminants. Sediment contamination from metals and organics has been linked to numerous health and ecological effects, extending from fish consumption advisories to endangered species listings. This dissertation research examines Ni bioavailability (simultaneously extracted metal (SEM)/acid volatile sulfide (AVS) models) and toxicity in five separate studies using Ni-spiked sediments in a variety of designs, and mainly with two different sediment types (low AVS, total organic carbon (TOC), and high AVS, TOC).

Two separate streamside mesocosm Ni experiments indicated …

Sea Surface Height: A Versatile Climate Variable For Investigations Of Decadal Change, Philip Robert Thompson

USF Tampa Graduate Theses and Dissertations

Decadal variations in climate are important, because the magnitude of sustained decadal change is often much larger than the often discussed background trends. Climate variability at interannual and longer periods is most often discussed in the context of climate modes defined by sea level pressure (SLP) and sea surface temperature (SST) patterns. However, SLP and SST are not capable descriptors of ocean dynamics. The approximately two decades of global sea surface height (SSH) measurements from satellite altimetry reveal substantial low-frequency redistributions of heat and salt in the ocean, which may or may not be related to defined climate modes. In …

Synthesis And Anti-Mrsa Activity Of Hydrophilic C3-Acylated N-Thiolated Β-Lactams And N-Acyl Ciprofloxacin-N-Thiolated Β-Lactam Hybrids, Biplob Bhattacharya

USF Tampa Graduate Theses and Dissertations

The Turos laboratory has been working with N-thiolated β-lactams for years trying to understand the mode of action and structural features it needs to have biological activity. Over the years new data has shown promising inhibitory activity against various microbes.

In this dissertation, a review of the vast amount of work carried out on N-thiolated β-lactams in Turos laboratory has been done and their novelty, in terms of structure and mechanism has been discussed. A complete outline of our work in the discovery and ongoing development of these compounds, starting from our initial, unexpected finding of antimicrobial activity for one …

Design Of Novel Inhibitors For Infectious Diseases Using Structure-Based Drug Design: Virtual Screening, Homology Modeling And Molecular Dynamics, Divya Ramamoorthy

USF Tampa Graduate Theses and Dissertations

The main aim of the study in this thesis was to use structure-based protocols to design new drugs for enzymes, DXS and DXR in the non mevalonate pathway. Another aim of this study was to identify the dimer interface in E.coli FabH as an allosteric binding site for designing new class of anti-infective drugs. We have attempted to identify potential inhibitors for DXS by docking the NCI Diversity set compounds, compound libraries available from GSK-MMV and St. Jude's Children's research center. FabH dimer interface has been identified as a potential target using SiteMap, Alanine mutagenesis and docking studies.

The first …

On The Spatial And Temporal Variability Of Upwelling In The Southern Caribbean Sea And Its Influence On The Ecology Of Phytoplankton And Of The Spanish Sardine (Sardinella Aurita), Digna Tibisay Rueda-Roa

USF Tampa Graduate Theses and Dissertations

The Southern Caribbean Sea experiences a strong upwelling process along the coast from about 61°W to 75.5°W and 10-13°N. In this dissertation three aspects of this upwelling system are examined: (A) A mid-year secondary upwelling that was previously observed in the southeastern Caribbean Sea between June-July, when land based stations show a decrease in wind speed. The presence and effects of this upwelling along the whole southern Caribbean upwelling system were evaluated, as well as the relative forcing contribution of alongshore winds (Ekman Transport, ET) and wind-curl (Ekman Pumping, EP). (B) Stronger upwelling occurs in two particular regions, namely the …

Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice

USF Tampa Graduate Theses and Dissertations

Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …

A Tarskian Informal Semantics For Answer Set Programming, Marc Denecker, Yuliya Lierler, Miroslaw Truszczyński, Joost Vennekens

Computer Science Faculty Proceedings & Presentations

In their seminal papers on stable model semantics, Gelfond and Lifschitz introduced ASP by casting programs as epistemic theories, in which rules represent statements about the knowledge of a rational agent. To the best of our knowledge, theirs is still the only published systematic account of the intuitive meaning of rules and programs under the stable semantics. In current ASP practice, however, we find numerous applications in which rational agents no longer seem to play any role. Therefore, we propose here an alternative explanation of the intuitive meaning of ASP programs, in which they are not viewed as statements about …

Practical And Methodological Aspects Of The Use Of Cutting-Edge Asp Tools, Marcello Balduccini, Yuliya Lierler

Computer Science Faculty Proceedings & Presentations

In the development of practical applications of answer set programming (ASP), encodings that use well-established solvers such as CLASP and DLV are sometimes affected by scalability issues. In those situations, one can resort to more sophisticated ASP tools exploiting, for instance, incremental and constraint ASP. However, today there is no specific methodology for the selection or use of such tools. In this paper we describe how we used such cutting-edge ASP tools on challenging problems from the Third Answer Set Programming Competition. We view this paper as a first step in the development of a general methodology for the use …

Weighted-Sequence Problem: Asp Vs Casp And Declarative Vs Problem-Oriented Solving, Yuliya Lierler, Shaden Smith

Computer Science Faculty Proceedings & Presentations

Search problems with large variable domains pose a challenge to current answer-set programming (ASP) systems as large variable domains make grounding take a long time, and lead to large ground theories that may make solving infeasible. To circumvent the “grounding bottleneck” researchers proposed to integrate constraint solving techniques with ASP in an approach called constraint ASP (CASP). In the paper, we evaluate an ASP system clingo and a CASP system clingcon on a handcrafted problem involving large integer domains that is patterned after the database task of determining the optimal join order. We find that search methods used by clingo …

On The Relation Of Constraint Answer Set Programming Languages And Algorithms, Yuliya Lierler

Computer Science Faculty Proceedings & Presentations

Recently a logic programming language AC was proposed by Mellarkod et al. (2008) to integrate answer set programming (ASP) and constraint logic programming. Similarly, Gebser et al. (2009) proposed a CLINGCON language integrating ASP and finite domain constraints. These languages allow new efficient inference algorithms that combine traditional ASP procedures and other methods in constraint programming. In this paper we show that a transition system introduced by Nieuwenhuis et al. (2006) to model SAT solvers can be extended to model the “hybrid” ACSOLVER algorithm by Mellarkod et al. developed for simple AC programs and the CLINGCON algorithm by Gebser et …

Organic And Composite Aerogels Through Ring Opening Metathesis Polymerization (Romp), Dhairyashil Mohite

Doctoral Dissertations

"Aerogels are open-cell nanoporous materials, unique in terms of low density, low thermal conductivity, low dielectric constants and high acoustic attenuation. Those exceptional properties stem from their complex hierarchical solid framework (agglomerates of porous, fractal secondary nanoparticles), but they also come at a cost: low mechanical strength. This issue has been resolved by crosslinking silica aerogels with organic polymers. The crosslinking polymer has been assumed to form a conformal coating on the surface of the skeletal framework by covalent bridging elementary building blocks. However, "assuming" is not enough: for correlating nanostructure with bulk material properties, it is important to know …

Synthesis And Structural And Electrochemical Characterization Of Novel Macrocyclic Vic-Dioxime Ligand And Its Mononuclear Transition And Nontransition Metal Complexes, Pervi̇n Deveci̇, Bi̇lge Taner, Zeynel Kiliç, Ali̇ Osman Solak, Emi̇ne Özcan

Turkish Journal of Chemistry

The reaction of N-(4-aminophenyl)aza-15-crown-5 (1) with anti-chlorophenylglyoxime (2) produces a novel azacrown ether containing vic-dioxime, N-(4-aminophenyl)aza-15-crown-5-phenylglyoxime (LH_2). LH_2 reacts with Ni(II), Cu(II), Co(II), Cd(II), and Zn(II) ions to yield the mononuclear transition and nontransition metal complexes [M(LH)_2] (M = Ni and Cu), [M(LH)_2(H_2O)_2] (M = Co), and [M(LH)(H_2O)(Cl)] (M = Cd and Zn). The structural features of LH_2 were studied using several techniques including elemental analysis, Fourier transform infrared spectroscopy (FT-IR), ultraviolet visible (UV-Vis), mass spectrometry (MS), 1-dimensional (1D) ^1H-NMR and ^{13}CNMR, distortionless enhancement by polarization transfer (DEPT) 2-dimensional (2D) heteronuclear single-quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC) techniques. …

A Systematic Study Of Transport, Magnetic And Thermal Properties Of Layered Iridates, Oleksandr B. Korneta

Theses and Dissertations--Physics and Astronomy

A unique feature of the 5d-iridates is that the spin-orbit interaction (SOI) and Coulomb interactions U are of comparable strength and therefore compete vigorously. The relative strength of these interactions stabilizes new exotic ground states that provide a fertile ground for studying new physics. SOI is proportional to Z^4 (Z is the atomic number), and it is now recognized that strong SOI can drive novel narrow-gap insulating states in heavy transition metal oxides such as iridates. Indeed, strong SOI necessarily introduces strong lattice degrees of freedom that become critical to new physics in the iridates. This dissertation thoroughly examines a …

Deciphering The Arrangement Of Dust In The Clumpy Tori Of Active Galactic Nuclei, Grant David Thompson

Theses and Dissertations--Physics and Astronomy

In the framework of active galactic nuclei (AGNs), a galaxy’s supermassive black hole is surrounded by a dusty torus whose clumpy configuration allows for either direct or obscured views toward the central engine. Viewing AGNs from different angles gives rise to a variety of AGN classifications; for example, the generic Type 1 AGN class requires the detection of optically broad emission lines, which arise from quickly moving material within the torus, whereas Type 2 AGNs lack these observations. While these viewing angles are not directly observable, synthetic torus models generated with CLUMPY provide a means to determine them along with …

Gis Data: Westmoreland County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Carl Hershner, Sharon A. Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Data

The 2012 Tidal Marsh Inventory update for Westmoreland County, 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 Hampton, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Data

The 2012 Tidal Marsh Inventory update for City of Hampton, 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.

Soft Skills Requirements In Software Development Jobs: A Cross-Cultural Empirical Study, Faheem Amed, Luiz Fernando Capretz, Salah Bouktif, Piers Campbell

Electrical and Computer Engineering Publications

Purpose: Most of the studies carried out on human factor in software development concentrate primarily on personality traits. However, soft skills which largely help in determining personality traits have been given comparatively little attention by researchers. The purpose of this paper is to find out whether employers’ soft skills requirements, as advertised in job postings, within different roles of software development, are similar across different cultures.

Design/methodology/approach: The authors review the literature relating to soft skills before describing a study based on 500 job advertisements posted on well-known recruitment sites from a range of geographical locations, including North America, Europe, …

Energy-Efficient Protocols And Systems For Wireless Sensor Networks And Smart Environments, Giacomo Ghidini

Computer Science and Engineering Dissertations

In a wireless sensor network, small computing devices, called sensors, sense the surrounding environment and relay the sensed data to a base station over a multi-hop wireless network, eventually processing them en-route. Wireless sensor networks and other devices, such as smartphones, smart meters, and smart appliances, cooperate in smart environments to obtain information about the environment, and then use this information to improve the experience of the users. Since most of these systems rely on battery power, there is a need for energy-efficient solutions for their operation. The objective of this dissertation is to design algorithms and protocols to improve …

Effective And Secure Use Of Human Relation Networks, Na Li

Computer Science and Engineering Dissertations

With the advent of Web 2.0 and advanced techniques of wireless devices (e.g., smart phones or iPhones), Online Social Networks (OSNs) and Mobile Social Networks (MSNs) are becoming integral part of our lives as two main digital social communities. Data collected from people's communication on OSNs and MSNs contains valuable information which makes human relationships more visible as compared to their existence in our physical world. For instance, the friend list on a user's profile page on Facebook clearly tells us the user's friendships with other users. Moreover, the short-range wireless communication techniques (e.g., Bluetooth) also enable us to “sense” …

Biomarkers: Review And Application To The Eagle Ford Shale Formation, Ugochukwu Ononogbu

Earth & Environmental Sciences Theses

Biomarkers have become an integral part of oil exploration. Gas Chromatography (-Mass Spectrometry) was performed to an oil sample to acquire biomarkers from the sample.The presence, lack of, or abundance of a given compound (or biomarker) in the geochemicalresults of an oil sample depict(s) a property or properties of the source rock and the oil. Forexample, the abundance of pristane and lack of phytane in an oil sample are characteristic ofshale source rock, and the results from the Eagle Ford shale formation show a high pristane tophytane ratio.The Eagle Ford shale formation is cretaceous in age; the presence and absence …

A Late Holocene Meander-Braid Transition Of The Lower Missouri River Valley, Michele Viola Kashouh

Earth & Environmental Sciences Theses

Historically, the Lower Missouri River is known for being a temperate river that constantly and quickly reworks its floodplain with a braided network of channels; however, the river only recently became braided. Ox-bow lakes and landscape features resembling highly sinuous meandering loops mark the floodplain of the lower Missouri River Valley as scars of what was once a fully meandering Missouri River. The unanswered question then is, when did the lower Missouri River system change from meandering to braided? To answer this question we compared a series of newly created allostratigraphic maps of the lower Missouri River valley floor to …

Predicting The Ancient Occurrence Of Coal Deposits Using Paleoclimate Modelling, Mandi Beck

Earth & Environmental Sciences Theses

Coals are accumulated and consolidated remains of plant material, which means that in order to form coals, a certain amount of annual precipitation is required. This study uses paleo-precipitation data obtained from Fast Ocean Atmosphere Model (FOAM) and predicts where paleo-coal deposits might occur. All predicted coal localities were plotted on paleogeographic reconstructions (obtained from the PALEOMAP Project) for thirteen time intervals from the Early Carboniferous to present. Once these predicted coal deposits were plotted, observed coals from the Boucot et al., 2012 database were then plotted on the same reconstructed basemaps. The predicted coal deposits were then compared with …

Microfaunal Assemblages Of The Placid Shale (Missourian, Upper Pennsylvanian), Brazos River Valley, North-Central Texas, Brittany E. Meagher

Earth & Environmental Sciences Theses

The Pennsylvanian and lowermost part of the Permian strata in North-Central Texas is assigned to the Strawn, Canyon, and Cisco Groups. The Canyon Group is approximately equivalent to the middle-upper part of the Missourian (Upper Pennsylvanian) and crops out in the Brazos River valley in a generally northeast-southwest strip across Palo Pinto and Jack counties. The Canyon Group is subdivided into seven formations that contain several cycles of well-known clastic and carbonate units. The Placid Shale, one of the clastic units within the Canyon Group, consists of two cycles of gray, brown, olive sandstone/siltstone/mudstone with few thin limestone beds. It …

High Resolution Geochemistry Of The Cretaceous Eagle Ford Shale, Bee County, Texas, Lisa Michelle Moran

Earth & Environmental Sciences Theses

The Eagle Ford Formation of Bee County, Texas is a sporadically laminated carbonaceous dark mudrock. The depositional area of the Eagle Ford Formation stretches across the state of Texas in a northeast-southwest trend. Early studies of the Eagle Ford found the deposits to be rich in organic material but could not fully describe the formation due to the lack of outcrop exposure. Recent studies of the Eagle Ford Formation have begun to explore the sub-surface nature of the formation. Geochemical analyses of the J.A. Leppard #1 core from the southwestern portion of the formation was conducted to further constrain the …

Growth Rates Of The Harmful Alga Prymnesium Parvum: An Attempt To Identify The Salinity Threshold For Algal Blooms, James William Cody Black

Earth & Environmental Sciences Theses

Harmful algal blooms due to Prymnesium parvum have occurred in Texas for nearly three decades in waters of moderate salinity. More recently, blooms have occurred in locations such as West Virginia, in waters of very low salinity where pollution discharges are suspected to have increased salinity to levels that support growth of P. parvum. These observations raise the question, what is the lowest salinity at which this species of algae can cause toxic fish kills? Previous research based on field observations has suggested a salinity threshold of about 1.5 PSU for occurrence of blooms in Texas reservoirs in winter. Other …