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Laser Intensity Scaling Through Stimulated Scattering In Optical Fibers, Timothy H. Russell

Theses and Dissertations

The influence of stimulated scattering on laser intensity in fiber optic waveguides is examined. Stimulated Brillouin scattering (SBS) in long, multimode optical waveguides is found to generate a Stokes beam that propagates in the fiber LP01 mode. Additionally, the same process is found to combine multiple laser beams into a single spatially coherent source. Limitations in beam cleanup and combining are also investigated to identify ways to overcome them. The last portion of the dissertation theoretically examines suppression of stimulated Raman scattering in fibers to eliminate the restriction this imposes on the power of a fiber laser or amplifier. The …

Night Out Itinerary Creator, Jennifer Hood

Honors Capstone Projects and Theses

No abstract provided.

Reduced Order Modeling For High Speed Flows With Moving Shocks, David J. Lucia

Theses and Dissertations

The use of Proper Orthogonal Decomposition (POD) for reduced order modeling (ROM) of fluid problems is extended to high-speed compressible fluid flows. The challenge in using POD for high-speed flows is presented by the presence of moving discontinuities in the flow field. To overcome these difficulties, a domain decomposition approach is developed that isolates the region containing the moving shock wave for special treatment. The domain decomposition implementation produces internal boundaries between the various domain sections. The domains are linked using optimization-based solvers which employ constraints to ensure smoothness in overlapping portions of the internal boundary. This approach is applied …

Pedogenic Relationships In A Texas Vertisol Climosequence Defined By Geochemical Mass Balance Of Whole Soil And Chemistry Of Iron-Manganese Nodules, Cynthia A. Stiles

Doctoral Dissertations

Climosequence Vertisol profiles derived from the Upper Beaumont Formation in the Gulf Coastal Prairie physiographic province of Texas were examined for geochemical trends ascribed to different precipitation regimes. Mass-balance relationships were utilized for the comparisons. Compositional differences in zirconium (Zr) content between the solum and lower sub-soil precluded it use an immobile strain (volumetric change) indicator. This difference was correlated to sand weight percent (r² = 0.65**). Titanium (Ti) content did not shift correlatively with depth, thus making Ti the preferred strain index element for mass-balance calculations. Depths at which the Zr compositions shifted were not directly related to …

Diagenesis Of Upper Cambrian Mount Simon Sandstone In The Illinois Basin - Microscale Investigation Of Basinal Fluid Migration And Mass Transfer, Zhensheng Chen

Doctoral Dissertations

A series of investigations were conducted to evaluate microscale evidence for basinal fluid migration in the Illinois basin during diagenesis of the Upper Cambrian Mount Simon Sandstone. Samples were examined using transmitted light and cathodoluminescence (CL) petrography, fluid inclusion analysis, and Secondary Ion Mass Spectrometry (SIMS) analysis of ¹⁸O/¹⁶O ratios and trace element compositions. Preliminary investigation of in situ laser ablation ⁴⁰Ar-³⁹Ar age dating techniques on authigenic K-feldspar over growths was also completed.

Two major generations of quartz overgrowths are observed, on the basis of transmitted light and CL petrography and fluid inclusion studies. …

Two Body Dirac Equations And Nucleon Nucleon Scattering Phase Shift Analysis, Bin Liu

Doctoral Dissertations

In this dissertation, the nucleon-nucleon interaction is investigated by using the meson exchange model and the two body Dirac equations of constraint dynamics. This approach to the two body problem has been successfully tested for QED and QCD relativistic bound states. An important question we wish to address is whether or not this approach is also valid in the two body nucleon-nucleon scattering problem. This test involves a number of related problems.

First we must reduce our two body Dirac equations exactly to a Schr¨odinger-like equation. This can be done without making any assumptions or approximations and unlike other relativistic …

Slowstart Congestion Control For Fine-Grained Layered Multicast, Khalid Shaheen

Archived Theses and Dissertations

No abstract provided.

The Study Of Biological Membranes Using The Atomic Force Microscope, Brandy L. Perkins

Electronic Dissertations and Theses

In the past research, when a carbon nanotube enhanced cantilever was probed along a living cell membrane, carboxylic acid groups located at the tips of the nanotubes would interact with various groups on the surface of the membrane causing it to rupture. A method to re-derivatize the tips of the nanotubes through covalent bonding by allowing the amine groups to attach to the carboxylic acid groups was developed. This chemical change perhaps will allow one to probe a cell surface without rupturing it. Successful nanotube derivatization will eventually lead to a map of the surface of living cell membranes and …

Phytoremediation Of Lead By Chinese Tallow (Sapium Sebiferum) Plant, Oluwaseumi A. Odebunmi

Electronic Dissertations and Theses

Over the past several decades, health and environmental risks of pollution have become apparent. As a result, environmental regulations have been created to remediate areas where environmental contamination is tremendous, therefore, a low-cost alternative to the already existing technology is needed. Using plants to eliminate hazardous organic compounds from contaminated soils has been proposed as an efficient means of remediation. Phytoremediation is the direct use of living green plants to remediate soil, sludge, sediments and ground water contaminated with toxic compounds. The four processes of phytoremediation are rhizofiltration, phytoextraction, phytostabilization and phytodegradation. As they 'grow and develop, plants will use …

Image Compression By Wavelet Transform., Panrong Xiao

Electronic Theses and Dissertations

Digital images are widely used in computer applications. Uncompressed digital images require considerable storage capacity and transmission bandwidth. Efficient image compression solutions are becoming more critical with the recent growth of data intensive, multimedia-based web applications.

This thesis studies image compression with wavelet transforms. As a necessary background, the basic concepts of graphical image storage and currently used compression algorithms are discussed. The mathematical properties of several types of wavelets, including Haar, Daubechies, and biorthogonal spline wavelets are covered and the Enbedded Zerotree Wavelet (EZW) coding algorithm is introduced. The last part of the thesis analyzes the compression results to …

Challenges For The New West: Economic Impacts Of Wilderness In Nevada's Rural Counties, Lesley Regina Argo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Public lands designated as part of the National Wilderness Preservation System are removed from multiple-use management for protection of their natural condition. Opponents argue that "locking up" the natural resources on these lands through designation will undermine the rural economies in the west that are dependent upon extractive industries such as mining and logging. Proponents argue that the "Old West" reliance on extractive industries is declining and, in the "New West", wilderness promotes economic development in rural communities by preserving the amenity values that draw population and employment to the region. Characteristics of Nevada's economy, population and land challenge the …

A Framework For Multilingual Information Processing, Steven Edward Atkin

Theses and Dissertations

Recent and (continuing) rapid increases in computing power now enable more of humankind's written communication to be represented as digital data. The most recent and obvious changes in multilingual information processing have been the introduction of larger character sets encompassing more writing systems. Yet the very richness of larger collections of characters has made the interpretation and processing of text more difficult. The many competing motivations (satisfying the needs of linguists, computer scientists, and typographers) for standardizing character sets threaten the purpose of information processing: accurate and facile manipulation of data. Existing character sets are constructed without a consistent strategy …

Magmatic Enclaves And Evidence For Magma Mixing In The Oak Point Granite, Deer Isle, Maine, Usa, Ben Johnston

Electronic Theses and Dissertations

The Coastal Maine Magmatic Province (CMMP) consists of over 100 post tectonic plutons with ages varying from Silurian to Carboniferous. Predominately, plutons are either felsic or mafic with little intermediate material. Several plutons within the CMMP show evidence for direct interaction of contemporaneous mafic and felsic magmas. These are classified as Mafic and Silicic Layered Intrusions (MASLI), a specific group of plutons with characteristics indicative of mafic magma replenishment into silicic magma chambers. While the Maine coast contains several MASLI type plutons, other plutons in the CMMP contain less definitive, more cryptic evidence that suggests interaction of mafic and silicic …

Fluorescence And Light Scattering Studies Of Aromatic Polymers Near The Critical Concentration C*, M.Sean Healy

Seton Hall University Dissertations and Theses (ETDs)

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Pan, Ppn And Mpan Measurements And The Quantitative Relationship Of Pan And Mpan In Biogenic Hydrocarbon Conditions, Chen Wangchun

Masters Theses

Simultaneous measurements of PAN, PPN and MPAN were made during the SOS 1999 Nashville campaign at Dickson site. The PANs data at this site were rich and complex. PAN and MP AN showed obvious diurnal change but PPN did not during this period. PAN and ozone have a clear positive relationship. Due to the special location of the site, winds from different directions bring anthropogenic hydrocarbons (AHCs) or biogenic hydrocarbons (BHCs) to the site. The data showed that the influence of AHCs and BHCs on PANs compounds varied on different days. Average values of PAN/PPN and PAN/MPAN from MLR may …

Relationships Between Oceanographic Satellite Data And Alexandrium Distributions In The Gulf Of Maine, Remy Martin Luerssen

Electronic Theses and Dissertations

An examination is made of the qualitative and quantitative relationships between satellite derived sea-surface temperature (SST) and chlorophyll patterns and the distribution of Alexandrium, the toxic dinoflagellate species responsible for HABs in the GOM. Daily images coincident with five ECOHAB survey cruises in 1998 and 2000 are composited over each cruise period to create mean patterns for each sample period. Contours of surface Alexandrium cell concentrations are superimposed on the images as well as images showing the strength and location of SST frontal zones to examine qualitative relationships. Results indicate that high concentrations of Alexandrium are located primarily in the …

Effects Of An Increasing Harbor Seal Population On Changes In Sites Used For Pupping, Nikolina Guldager

Electronic Theses and Dissertations

Aerial survey data from 198 1 to 1997 of an increasing harbor seal (Phoca vitulina concolor) population in Penobscot and Blue Hill bays, Maine, were used to evaluate spatial and temporal patterns of use of pupping sites by mother-pup pairs. Pupping sites refer to haul-out sites where pups were observed during surveys, and are assumed to be used consistently from birth to weaning. Sites with pups were spatially clustered to remove spatial auto-correlation, reduce temporal variability and provide biologically cohesive and independent sample units. Spatial, temporal and habitat analyses were completed for 2 spatial scales: individual sites and …

Modeling Intersections Of Geospatial Lifelines, Ramaswam Hariharan

Electronic Theses and Dissertations

Modeling moving objects involves spatio-temporal reasoning. The continuous movements of objects in space-time captured as discrete samples form geospatial lifelines. Existing lifeline models can represent the movement of objects between samples from most likely location to all possible locations. This thesis builds on a model called lifeline bead and necklace that captures all the possible locations of moving objects. Beads are 3-dimensional representations of an object's movements and a series of beads form a necklace. The extent of finding the possible locations is constrained by the speed of movement of the objects. Intersections of lifelines occur when two or more …

Evolution Of Sprague Neck Bar, Machias Bay, Maine, Rebecca A. Nestor

Electronic Theses and Dissertations

Sprague Neck Bar is a recurved barrier spit located in Machias Bay, Maine. Principle geomorphic features associated with Sprague Neck Bar include bedrock, coastal bluffs, till in grounding line (the Pond Ridge Moraine) and washboard moraines, mudflats, sand and gravel beaches, and a salt marsh. Sprague Neck Bar is attached to the western end of the Pond Ridge Moraine (Sprague Neck) and extends northward toward the head of Machias Bay for 845 meters before the system recurves to the southeast for 232 meters. The recurve system forms a broad tidal flat with evidence for northward and eastward migration of the …

Characterization Of Organo-Tin And Organo-Mercury Compounds With Electrospray Mass Spectrometry, Kan Zhu

Masters Theses

Metal-containing compounds are often found as pollutants in the environment. Obtaining speciation information about these compounds is important to understanding toxieity and bioaccumulation. Electrospray Mass Spectrometry (ESMS) is a technique that has the potential to provide rapid and direct speciation information of solution phase metal compounds. The ionization behavior of chemical species is related to their electron affinities. The higher the electron affinity, the easier it will be reduced during the ionization process. Additionally, solvent with different polarity and surface tension will also affect the ionization and reduction products. Organo-tin compounds with more alkyl groups will be ionized more efficiently, …

Variables Influencing Nest Success Of Eastern Wild Turkeys In Connecticut: Nesting Habitat, Home Range-Scale Fragmentation, And Nest Attentiveness, Shelley M. Spohr

Electronic Theses and Dissertations

Nest success is the most important demographic parameter influencing rates of population change of eastern wild turkeys (Meleagris gallopavo si1vestris) and many variables operating at multiple spatial and temporal scales may influence whether a nest is successful. Most studies of nest success and survival of turkeys have occurred in forested or agricultural landscapes; variables influencing nest success have not been studied in suburban landscapes. My objectives were to: 1 ) quantify survival and reproductive parameters of eastern wild turkey hens in the suburban environment of southeastern Connecticut and compare results to studies conducted in other northeastern states; 2) …

Anthropogenic Influences And Meteorological Effects: How They Are Changing The Sand Beaches In Southern Maine, Heather W. Heinze

Electronic Theses and Dissertations

Although sand beaches in southern Maine comprise only a small segment of the coastline, they are economically important to the state. From September 1999-March 2001, volunteers made monthly topographic profiles along nine beaches in southern Maine to monitor changes. The volunteers used the Emery Method of beach profiling to take simultaneous measurements at spring low tide. The beaches are significantly different with respect to physiography, incident wave energy and direction, available sediment supply and extent of development. An average of the profiles for each category demonstrates that the undeveloped beaches experienced regular seasonal fluctuations and a consistent berm elevation from …

Gametogenic Cycles Of Marine Mussels, Mytilus Edulis And Mytilus Trossulus, In Cobscook Bay, Maine, Aaron P. Maloy

Electronic Theses and Dissertations

The Mytilus edulis species complex includes three smooth-shelled blue mussels, M. edulis (Linnaeus 1 75 8), M trossulus (Gould 1 850), and M galloprovincialis (Lamarck 18 19). When any two of theses species occur sympatrically, hybridization and backcrossing of hybrid and parental genotypes is evident. Despite introgression of genes between taxa their genetic integrity is maintained. To test the hypothesis that a temporal variation in species-specific spawning times is the mechanism limiting hybridization and maintaining genetic integrity in a M edulis and M. trossulus hybrid zone in eastern Maine, mussels were sampled on monthly to semi-monthly intervals throughout 2000 from …

The Effects Of Temperature On The Survival, Growth And Development Of Larvae Of Two Blue Mussel Species (Mytilus Edulis And Mytilus Trossulus), Susan Hayhurst

Electronic Theses and Dissertations

Factors affecting the distribution of Mytilus edulis and Mytilus trossulus in the Gulf of Maine are of great interest because of the blue mussel's economic and ecological importance. Genetic surveys of blue mussel populations indicate that eastern Maine represents the southern distributional limit for M. trossulus but that M. edulis is common throughout the Gulf of Maine. Because hydrographic features in the Gulf of Maine confound temperature variation and larval dispersal patterns, the relative importance of these potential range-limiting mechanisms cannot be ascertained from the distribution of adult mussels. Given that larvae are more vulnerable than adults to temperature extremes, …

The Role Of Water Motion In Algal Reproduction, Richard Gordon

Electronic Theses and Dissertations

Environmental conditions, such as water motion, can influence fertilization success and spore dispersal in marine algae. Previous studies on fucoid algae showed that gamete release is restricted to, or enhanced by, periods of low water motion. Few other algal taxa have been investigated, however, including species with an alternation of generations. I investigated gamete and spore release in the macroalgae Alaria esculenta and Ulva lactuca, as well as in the diatom Pseudo-nitachia multiseries to determine if water motion is inhibitory or stimulates propagule production and release. I used orbital shakers to simulate water motion; these were interspersed with stationary platforms …

Solid Waste Management In Oil And Gas Pipelines Application To Asab Field, Abdulqader M Alkamali

Theses

Managing solid waste, and any other wastes in general, is an environmental need, an economical choice and a legal requirement. Preserving the environment while lowering the cost becomes a necessity when liabilities are of concern.

Solid wastes generated from oil and gas industrial activities are very diverse in their characteristics, large in their amounts and many of which are hazardous in nature. Thus, the need to manage these wastes is an obvious mandate. Oil and gas industrial activities include exploration, drilling, production, processing, refining, manufacturing and exporting. Associated with these activities, other supporting services; such as, maintenance, civil, transportation, storage, …

Petrological And Geochemical Analyses And Economic Potential Of Some Milestones And Siliceous Rocks In Northern United Arab Emirates., Mohammed Ahmed A. Ibrahim

Theses

Combined microscopic, heavy mineral, X-ray diffraction and chemical analyses have been carried out on the Jurassic limestone, the upper cretaceous Hawasina cherts and the coastal and inland sand dunes in several localities in the Ras Al Khaimah Emirate. The obtained results revealed that a number of represents cherts subfacies; namely: ferruginous radiolarian ribbon chert, carbonaceous radiolarian ribbon chert, colloform ribbon chert, calcareous chert and siliceous mud stone. These rocks consist of (in order of decreasing abundance): quartz, calcite, dolomite and hematite. The carbonate rocks are made up of lime mudstone, wackestone; pack stone and, rarely, crystalline limestone. Various types of …

A Meta-Analysis And Risk Assessment Of Heavy Metal Uptake In Common Garden Vegetables., Trent David Lecoultre

Electronic Theses and Dissertations

Peer reviewed literature was searched to identify research pertaining to the uptake of heavy metals (As, Cd, Pb and Zn) by vegetables (cabbage, carrot, lettuce, and radish). The objectives of this research were to 1) determine the relationship between heavy metal concentrations in the soil and heavy metal concentrations in vegetables, and 2) determine the level of risk associated with exposure to heavy metals through ingestion of contaminated vegetables. Highly variable estimates and biologically implausible regression equations resulted from this meta-analysis. Exposure to arsenic through the ingestion of lettuce grown on contaminated soil significantly increases cancer risk, especially in children. …

The Suitability Of Reclaimed Agricultural Lands Along The Lower Colorado River For Native Riparian Habitat Restoration, Patti Aaron

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this paper is to determine the suitability of agricultural lands for use in native riparian restoration efforts under development for the Lower Colorado River Multi-Species Conservation Program. Assuming these fields are productive for crops, would they be productive for cottonwood-willow restoration? There are two aspects to consider: (1) the edaphic conditions required for three major LCR agricultural crops; alfalfa, cotton, and wheat, and (2) whether those conditions are consistent with the conditions required for the restoration of native LCR riparian habitat, primarily Fremont cottonwood (Populus fremontii) and Goodding willow (Salix gooddingii). Using the case study research approach …

Real-Time Distributed Scheduling In Non-Guaranteed Networks Within A Quality Of Service Framework, Hisham Nabil El-Zahhar

Archived Theses and Dissertations

No abstract provided.