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Full-Text Articles in Physical Sciences and Mathematics

Uptake Of Gold Nanoparticles In An Algae - Daphnid Food Chain, Matthew Osborne-Koch Dec 2009

Uptake Of Gold Nanoparticles In An Algae - Daphnid Food Chain, Matthew Osborne-Koch

All Theses

Nanoparticle entry into the environment can result in deleterious effects to exposed organisms, disruption of ecological processes, and accumulation within the wood web. Gold nanoparticles (AuNPs), which are classified as zero-valent metals, are of significant interest due to their use in a variety of applications including electrical, biomedical, catalytic, magnetic, and optical technology. The wide range of uses for AuNPs can be attributed to a combination of the unique physical properties of the element gold (i.e. density, conductivity, stability, etc.) and the diversity of sizes, shapes, and surface compositions that can be achieved through manipulation of AuNP synthesis. While previous …


A Study Of The Mesosphere-Lower Thermosphere: Noctilucent Cloud Observations And Rocket Borne Density Measurements, Shelton Simmons Dec 2009

A Study Of The Mesosphere-Lower Thermosphere: Noctilucent Cloud Observations And Rocket Borne Density Measurements, Shelton Simmons

All Theses

Herein, a study of a noctilucent cloud, NLC, display from 17 July 2007 is analyzed. A photogrammetric analysis was applied to time lapsed photographs taken from two observation sites, RŸgen and KŸhlungsborn, Germany. Both Kelvin-Helmholtz instabilities and internal gravity waves were identified during the NLC display based on the typical characteristics of such waves in the mesopause region. With the two observation sites, the location of details can be identified with an accuracy of ±0.125¡ longitude and ±0.5¡ latitude. A gravity wave with a wavelength of 50km and Kelvin-Helmholtz instability or gravity wave of wavelength 16.5km were observed. The 16.5km …


Analysis Of Mercury And Lead In Birds Of Prey From Gold-Mining Areas Of The Peruvian Amazon, Peggy Shrum Dec 2009

Analysis Of Mercury And Lead In Birds Of Prey From Gold-Mining Areas Of The Peruvian Amazon, Peggy Shrum

All Theses

This study was conducted to determine levels of lead and mercury in the raptors of the South-eastern Peruvian Amazon. The study took place within the Los Amigos Conservation Concession in Madre de Dios, Peru. Eighty-six raptors from among sixteen species were captured with Bal-Chatri traps. From each individual, feather samples were obtained for mercury analysis and blood was taken for lead analysis. Each raptor was then released without incident or injury.
Mercury amalgamation for gold extraction is widely used by small-scale, transient mining operations, which are numerous along the rivers and creeks in the tropical forests and other locations in …


Light Beaming From A Single Subwavelength Metal Slit, Pengyu Chen Dec 2009

Light Beaming From A Single Subwavelength Metal Slit, Pengyu Chen

All Theses

In this thesis, light transmission through a single sub-wavelength slit in a silver thin film with periodic gratings at the exit side of the slit has been studied in both the visible and mid-infrared wavelength ranges.
In the visible wavelength range, we first investigate the enhancement of plasmonic light beaming efficiency by near field resonance in a subwavelength metallic slit-groove beaming structure. We show that by varying the film thickness and the separation distance of the beaming grating, the intensity of the near field can be greatly enhanced by resonance, which leads to the increase of the beaming efficiency. Moreover, …


The Effects Of Pulsed Exposures Of Suspended Clay On The Survival, Growth, And Reproduction Of Daphnia Magna, Sarah Robinson Dec 2009

The Effects Of Pulsed Exposures Of Suspended Clay On The Survival, Growth, And Reproduction Of Daphnia Magna, Sarah Robinson

All Theses

Suspended sediments are a natural component of aquatic ecosystems but anthropogenic activity such as land development can result in significant increases, especially following rain events due to surface erosion. Continuous exposures of suspended clay and silt have been shown to effect growth and reproduction of Cladocera, leading to a decrease in population growth rate. The mechanism of clay toxicity in these filter-feeding organisms is clogging of the gut tract resulting in decreased food uptake and assimilation. When placed in clean water, daphnids can purge clay from their gut and recover. In many surface waters, aquatic organisms experience episodic exposures of …


Risk Assessment Of Bird Aircraft Strike Hazard For Grassland Birds At The Mcentire Air National Guard Station, Eastover, South Carolina, Marla Hamilton Dec 2009

Risk Assessment Of Bird Aircraft Strike Hazard For Grassland Birds At The Mcentire Air National Guard Station, Eastover, South Carolina, Marla Hamilton

All Theses

ABSTRACT
There are strict regulations surrounding vegetation management at military airfields for the purpose of reducing Bird Aircraft Strike Hazards (B.A.S.H.). At military installations vegetation heights are set between 17 to 38 cm to discourage the use of animal species such as flocking birds, soarers (e.g. raptors), large wading birds (e.g. herons), and waterfowl that create hazards to flying aircraft. Within designated clear zones, managers have typically promoted the growth of non - non-native grasses without much consideration for how these plantings might impact B.A.S.H. potential, bird occupancy, or avian conservation. Grasslands and grassland associated avifauna are among the 'highest …


An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi Dec 2009

An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi

All Theses

To meet the increasing demand for monitoring of the physical world, there has been an increase in the development of wireless sensor network applications. The TinyOS platform has emerged as a de facto standard for developing these applications. The platform offers a number of advantages, with its support for concurrency, power-efficient operation, and resource-constrained hardware chief among them. However, the benefits come at a price. Even without the TinyOS platform, the inherent parallel and distributed nature of these applications makes it difficult for developers to reason about program behavior. Further, the TinyOS programming model adopts
asynchronous, split-phase execution semantics. Developers …


Roost Selection By Rafinesque's Big-Eared Bats, Corynorhinus Rafinesquii, In Congaree National Park - A Multiscale Approach, Jessica Lucas Dec 2009

Roost Selection By Rafinesque's Big-Eared Bats, Corynorhinus Rafinesquii, In Congaree National Park - A Multiscale Approach, Jessica Lucas

All Theses

Little is known about natural roost selection of Rafinesque's big-eared bats, Corynorhinus rafinesquii , throughout their range. The objectives of this study were to determine roost use and selection of big-eared bats in the Upper Coastal Plain of South Carolina at multiple spatial scales and test whether roost use and selection differed between maternity colonies and solitary individuals. The study was conducted May-August 2006 and 2007 in Congaree National Park which contains extensive areas of old-growth bottomland forest. Roost trees were located via tree searches and radio-telemetry and I used univariate tests and multiple logistic regression to compare tree, stand, …


Semantic Search, Anup Sawant Dec 2009

Semantic Search, Anup Sawant

All Theses

The thesis describes a Semantic approach towards web search through a stand-alone Java application. An Ontology Web Language(OWL) model is used to build a knowledge database related to different types of Organisms. The goal is to guide the Google web search engine using this OWL model. In the rst approach towards Semantic web search, an inference engine called CLIPS is used and in the second aproach, the Protege-OWL API is used. The thesis goes in detail about the design,
working and comparison of these two approaches. The thesis also deals with design approach for enhancement of the OWL model, once …


Sparse Representations In Power Systems Signals, Jack Cooper Aug 2009

Sparse Representations In Power Systems Signals, Jack Cooper

All Theses

This thesis seeks to detect transient disturbances in power system signals in a sparse framework. To this end, an overcomplete wavelet packet dictionary and damped sinusoid dictionary are considered, and for each dictionary Matching Pursuit is compared with Basis Pursuit. Previous work in developing waveform dictionary theory and sparse representation is reviewed, and simulations are run on a test signal in both noisy and noiseless environments. The solutions are viewed as time-frequency plane tilings to compare the accuracy and sparsity of these algorithms in properly resolving optimal representations of the disturbances. The advantages and disadvantages of each combination of dictionary …


Portfolio Selection Problem Under Uncertainty And Risk, Dimitri Nowak Aug 2009

Portfolio Selection Problem Under Uncertainty And Risk, Dimitri Nowak

All Theses

The purpose of this research is the investigation of a portfolio problem in an uncertain environment. Given possible investments with random performance depending on uncertain environmental settings the objective is to establish a methodology for construction of a portfolio which is non-dominated with respect to second order stochastic dominance and whose return distribution is preferable for a least risk decision maker.


Analysis Of The Neutral Wind Profiles From The Hex Ii Experiment, Tyler Scott Aug 2009

Analysis Of The Neutral Wind Profiles From The Hex Ii Experiment, Tyler Scott

All Theses

The HEX II sounding rocket experiment was carried out on February 14, 2007, during active geomagnetic conditions. Three rockets released trimethyl aluminum (TMA) chemical tracer trails to measure the neutral winds. Three neutral wind profiles obtained from the upleg trails are presented. The profiles are characterized by a strong wind peak around 113 km altitude in the northwestward direction. Below the peak, the winds exhibit strong shear and a smaller wind peak at around 103 km in the southeastward direction. The wind magnitudes are too strong to be attributed to tidal forcing. Above 120 km the winds are consistently to …


Single Command Rendering With Sun Grid Engine, William Robinson Aug 2009

Single Command Rendering With Sun Grid Engine, William Robinson

All Theses

According to the Autodesk website, Autodesk Maya software is a powerful, integrated 3D modeling, animation, visual effects, and rendering solution. While this statement is true in every sense, one quality that this software and its competitors lack is in the area of resource management. Though not as critical to the other tasks in the production line, resource management is a crucial component of successful rendering. Until recently, Digital Production Arts students have been left to their own means to manage the rendering process; however, with the use of Sun Grid Engine, rendering tasks can be simplified to a single-command process, …


Deploying And Maintaining A Campus Grid At Clemson University, Dru Sepulveda Aug 2009

Deploying And Maintaining A Campus Grid At Clemson University, Dru Sepulveda

All Theses

Many institutions have all the tools needed to create a local grid that aggregates commodity compute resources into an accessible grid service, while simultaneously maintaining user satisfaction and system security. In this thesis, the author presents a three-tiered strategy used at Clemson University to deploy and maintain a grid infrastructure by making resources available to both local and federated remote users for scientific research. Using this approach virtually no compute cycles are wasted. Usage trends and power consumption statistics collected from the Clemson campus grid are used as a reference for best-practices. The loosely-coupled components that comprise the campus grid …


Synthesis Of Polymers Featuring Novel Diphosphines, Eleanor Tennyson Aug 2009

Synthesis Of Polymers Featuring Novel Diphosphines, Eleanor Tennyson

All Theses

This report details the synthesis of functionalized platinum-based metallopolymers featuring m-terphenyl-scaffolded and light-harvesting phosphine ligands. Substituents placed on both the phosphine and pendant alkynyl units can enhance the optical activity of the metallopolymers depending on their inherent properties. The presence of the platinum metal atom can be exploited to increase conductivity of the molecule and promises to be a unique and valuable modification for polymers to be used in light emitting diodes and photovoltaics. Light-harvesting phosphines prepared in the course of the metallopolymer development have also been used to prepare luminescent polyelectrolytes that prove valuable for well-defined composite film formation …


Phenomenological Investigation Of The Effectiveness Of A Cooperative Problem-Based Laboratory And A Metacognitive Problem-Solving Exercise, Todd Gatlin Aug 2009

Phenomenological Investigation Of The Effectiveness Of A Cooperative Problem-Based Laboratory And A Metacognitive Problem-Solving Exercise, Todd Gatlin

All Theses

Problem-solving has been described by many as the most important goal of chemistry teaching and learning. Solving real problems requires not only cognitive abilities but also a regulation of those abilities-metacognition. In fact, metacognition is recognized as having considerable impact on problem-solving success and learning. Recent research focused on the development of interventions designed to enhance the use of metacognition. The main objective of this study was to determine 'how' and 'why' two interventions were effective in increasing students' metacognitive use, and problem-solving abilities. Therefore, this study represents the qualitative portion of a sequential explanatory mixed-methods study; Qualitative evidence was …


Local Adaptive Smoothing In Kernel Regression Estimation, Qi Zheng Aug 2009

Local Adaptive Smoothing In Kernel Regression Estimation, Qi Zheng

All Theses

We consider nonparametric estimation of a smooth regression function of one variable. In practice it is quite popular to use the data to select one global smoothing parameter. Such global selection procedures cannot sufficiently account for local sparseness of the covariate nor can they adapt to local curvature of the regression function. We propose a new method to select local smoothing parameters which takes into account sparseness and adapts to local curvature of the regression function. A Bayesian method allows the smoothing parameter to adapt to the local sparseness of the covariate and provides the basis for a local cross …


Structural Role Of Pseudouridines In The Peptidyl Transferase Center Of Human 28s Ribosomal Rna, Chris Mart Aug 2009

Structural Role Of Pseudouridines In The Peptidyl Transferase Center Of Human 28s Ribosomal Rna, Chris Mart

All Theses

The human ribosome is an RNA-protein complex responsible for protein synthesis in the cell. Crystal structures of bacterial ribosomes solved to date depict no protein sidechains within the catalytic core, or peptidyl transferase center (PTC). This region of the human ribosome comprises approximately 230 highly conserved nucleotides. Notably, several of the uridine bases clustered within the human PTC are post-transcriptionally modified to pseudouridines, as compared with bacterial analogues. Pseudouridines are base-rotated uridines, linked to their sugar moieties through C5-C1' linkages, affording additional hydrogen-bond donor groups at the N1 position of their rings. A connection was recently made between the absence …


A Spectroscopic Analysis Of V505 Persei And The Origin Of The Lithium Dip, Patrick Baugh Aug 2009

A Spectroscopic Analysis Of V505 Persei And The Origin Of The Lithium Dip, Patrick Baugh

All Theses

We study the observed Li Dip in stellar clusters and field stars, testing Rotationally Induced Mixing (RIM) by measuring Li abundances in a middle-aged (1.1±0.15 Gyr), metal poor ([Fe/H]=-0.15±0.03), short period binary, V505 Per, finding Li abundances of Log N(Li)=2.67±0.1 and 2.42±0.2 from the primary and secondary components, respectively. These abundances are significantly higher than observed abundances from single stars of similar metallicity and ZAMS Teff; as shown by comparison with NGC 752, and suggest that RIM may be a primary cause of the Li Dip.


A Study For Scalable Directory In Parallel File Systems, Yang Wu Aug 2009

A Study For Scalable Directory In Parallel File Systems, Yang Wu

All Theses

One of the challenges that the design of parallel file system for
HPC(High Performance Computing) has to face today is maintaining the
scalability to handle the I/O generated by parallel applications that
involve accessing directories containing a large number of entries and
performing hundreds of thousands of operations per second. Currently,
highly concurrent access to large directories is poorly supported in
parallel file systems. As a result, it is important to build a
scalable directory service for parallel file systems to support
efficient concurrent access to larger directories.
In this thesis we demonstrate a scalable directory service designed
for parallel …


Non-Rigid Multi-Modal Object Tracking Using Gaussian Mixture Models, Prakash Chockalingam Aug 2009

Non-Rigid Multi-Modal Object Tracking Using Gaussian Mixture Models, Prakash Chockalingam

All Theses

This work presents an approach to visual tracking based on dividing a target into multiple regions, or fragments. The target is represented by a Gaussian mixture model in a joint feature-spatial space, with each ellipsoid corresponding to a different fragment. The fragment set and its cardinality are automatically adapted to the image data using an efficient region-growing procedure and updated according to a weighted average of the past and present image statistics. The fragment modeling is used to generate a strength map indicating the probability of each pixel belonging to the foreground. The strength map provides vital information about new …


Accurate Tracking Of Objects Using Level Sets, Nalin Senthamil Aug 2009

Accurate Tracking Of Objects Using Level Sets, Nalin Senthamil

All Theses

Our current work presents an approach to tackle the challenging task of tracking objects in Internet videos taken from large web repositories such as YouTube. Such videos more often than not, are captured by users using their personal hand-held cameras and cellphones and hence suffer from problems such as poor quality, camera jitter and unconstrained lighting and environmental settings. Also, it has been observed that events being recorded by such videos usually contain objects moving in an unconstrained fashion. Hence, tracking objects in Internet videos is a very challenging task in the field of computer vision since there is no …


Optimization Models For Designing Spatially Compact Ecological Reserve Systems, Lakmali Weerasena Aug 2009

Optimization Models For Designing Spatially Compact Ecological Reserve Systems, Lakmali Weerasena

All Theses

Over the past decades, a number of mathematical models and solution techniques have been developed to preserve reserve sites for species and their natural habitats. Two optimization models for designing spatially compact ecological reserve systems are addressed here as zero-one integer programming problems. These formulations have a bicriteria objective function that is a combination of both boundary length and distance. The two formulations cluster the sites into a relatively small number of compact groups while preserving a required number of sites that contain a certain species using a given amount of resources. Two general types of approaches have been developed …


A Dual Algorithm For The Weighted Euclidean Distance Min-Max Location Problem In R^2 And R^3, Andrea Smith May 2009

A Dual Algorithm For The Weighted Euclidean Distance Min-Max Location Problem In R^2 And R^3, Andrea Smith

All Theses

A dual approach algorithm is given for the solution of the weighted min-max location problem with Euclidean distance in R^2 and R^3. Each subproblem is solved using a directional search procedure and by taking advantage of its geometric structure. An algebraic replacement rule is employed to update the subproblem.


Specific And Non-Specific Binding Of Proteins And Nucleic Acids On Chemically Modified Reticulated Vitreous Carbon Electrodes, Hemangi Shedge May 2009

Specific And Non-Specific Binding Of Proteins And Nucleic Acids On Chemically Modified Reticulated Vitreous Carbon Electrodes, Hemangi Shedge

All Theses

Proteins and nucleic acids play major roles in many important biological processes. Specific and rapid detection of these biomolecules is important for early and precise diagnosis of various genetic diseases and other medical conditions. However, accurate and inexpensive detection of proteins and nucleic acids has always been a challenge. One of the obstacles is their non-specific adsorption on the sensor surface which leads to the conformational changes in the proteins, sometimes causing their denaturation. The non-specific adsorption on the surface also leads to sensor fouling which induces changes in the availability of active sensor surface for detection of analytes and …


Evaluating The Use Of Snmp As A Wireless Network Monitoring Tool For Ieee 802.11 Wireless Networks, Robert Johnson May 2009

Evaluating The Use Of Snmp As A Wireless Network Monitoring Tool For Ieee 802.11 Wireless Networks, Robert Johnson

All Theses

The increasing popularity of wireless networks has led to instances of high utilization and congestion, some of which have resulted in an interruption of network service. A thorough understanding of how IEEE 802.11 wireless networks operate is crucial to predicting and preventing future interruptions. There have been many studies performed on wireless networks. Of those that have captured data from the wireless side, most have used a form of wireless network monitoring known as Vicinity Sniffing (wireless sniffing from a location that is physically close to an access point to be in the broadcast range) as the primary means of …


Construction Of A Dimension Two Rank One Drinfeld Module, Catherine Trentacoste May 2009

Construction Of A Dimension Two Rank One Drinfeld Module, Catherine Trentacoste

All Theses

Consider Fr[t] where r = pm for some prime p and m in the natural numbers. Let f(t) be an irreducible square-free polynomial with even degree in Fr[t] so that the leading coeffcient is not a square
mod Fr. Let A = L = Fr[t][\sqrt{f(t)}].
We will examine the basic set-up required for a dimension two rank one Drinfeld module over L along with an explanation of our choice of f(t). In addition we will show the construction for the exponential function.


Acceleration Methodology For The Implementation Of Scientific Applications On Reconfigurable Hardware, Phillip Martin May 2009

Acceleration Methodology For The Implementation Of Scientific Applications On Reconfigurable Hardware, Phillip Martin

All Theses

The role of heterogeneous multi-core architectures in the industrial and scientific computing community is expanding. For researchers to increase the performance of complex applications, a multifaceted approach is needed to utilize emerging reconfigurable computing (RC) architectures. First, the method for accelerating applications must provide flexible solutions for fully utilizing key architecture traits across platforms. Secondly, the approach needs to be readily accessible to application scientists. A recent trend toward emerging disruptive architectures is an important signal that fundamental limitations in traditional high performance computing (HPC) are limiting break through research. To respond to these challenges, scientists are under pressure to …


Water Quality Guidelines And Water Quantity Analysis With Application To Construction Of A Pilot-Scale Wetland Treatment System, Minh Phung Pham May 2009

Water Quality Guidelines And Water Quantity Analysis With Application To Construction Of A Pilot-Scale Wetland Treatment System, Minh Phung Pham

All Theses

A searchable database consisting of compiled water reuse guidelines was created as a screening tool for decision-analysis for potential beneficial reuse in 1) irrigation, 2) livestock watering, 3) aquaculture, and 4) drinking (potable) water. Data compiled from literature for the four water reuses (FWR) yielded guideline values for over 50 water quality parameters, including concentrations of inorganic and organic constituents as well as general water chemistry parameters. These water quality guidelines can be used to identify constituents of concern in water, to determine levels to which constituents must be treated for water reuse applications, and to assess the suitability of …


Testing The Individual Effective Dose Hypothesis, Hung Vu May 2009

Testing The Individual Effective Dose Hypothesis, Hung Vu

All Theses

The assumption of the individual effective dose is the basis for the probit method used for analyzing dose or concentration – response data. According to this assumption, each individual has a uniquely innate tolerance expressed as the individual effective dose (IED) or the smallest dose that is sufficient to kill it. An alternative to IED, stochasticity suggests that individuals do not have uniquely innate tolerance; deaths result from random processes occurring among similar individuals. While the probit method has been used extensively in toxicology the underlying assumption has not been tested rigorously. The goal of this study was to test …