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Ambient Pressure Organic Semiconductor Thin Film Growth By Ambient Axisymmetric Spray, Kevin A. (Kevin Anthony) Bufkin 2010 Western Washington University

Ambient Pressure Organic Semiconductor Thin Film Growth By Ambient Axisymmetric Spray, Kevin A. (Kevin Anthony) Bufkin

WWU Graduate School Collection

Interest in using organic semiconductors in applications such as large area displays, photovoltaic devices, and radio frequency identification tags stems in part from their prospects for enabling significantly reduced manufacturing costs compared to traditional inorganic semiconductors. However many of the best performing prototype devices produced so far have involved expensive or time-consuming fabrication methods, such as the use of single crystals or thin films deposited under high vacuum conditions. This thesis examines a new approach for growing low molecular weight organic crystalline films at ambient conditions based on an organic vapor-liquid-solid growth (OVLS) mechanism using thermotropic nematic liquid crystal (LC ...


Delay, Cost And Infrastructure Tradeoff Of Epidemic Routing In Mobile Sensor Networks, Shan Zhou, Lei Ying, Srikanta Tirthapura 2010 Iowa State University

Delay, Cost And Infrastructure Tradeoff Of Epidemic Routing In Mobile Sensor Networks, Shan Zhou, Lei Ying, Srikanta Tirthapura

Electrical and Computer Engineering Conference Papers, Posters and Presentations

This paper studies the delay, cost and infrastructure tradeoff of epidemic routing in mobile sensor networks. We consider a mobile sensor network with M mobiles and B static base stations. The mobile sensors collect information when moving around and need to report the information to the base stations. Three different epidemic routing schemes --- target epidemic routing, uncontrolled epidemic routing and controlled epidemic routing --- are analyzed in this paper. For each of the three schemes, we characterize the scaling behaviors of the delay, which is defined to be the average number of time slots required to deliver a message, and the ...


Improving Accuracy Of Large-Scale Prediction Of Forest Disease Incidence Through Bayesian Data Reconciliation, Ephraim M. Hanks 2010 Utah State University

Improving Accuracy Of Large-Scale Prediction Of Forest Disease Incidence Through Bayesian Data Reconciliation, Ephraim M. Hanks

All Graduate Plan B and other Reports

Increasing the accuracy of predictions made from ecological data typically involves replacing or replicating the data, but the cost of updating large-scale data sets can be prohibitive. Focusing resources on a small sample of locations from a large, less accurate data set can result in more reliable observations, though on a smaller scale. We present an approach for increasing the accuracy of predictions made from a large-scale eco logical data set through reconciliation with a small, highly accurate data set within a Bayesian hierarchical modeling framework. This approach is illustrated through a study of incidence of eastern spruce dwarf mistletoe ...


Grading Practice Influence On The Value Of An Assigned Grade, Carrie Bala 2010 Utah State University

Grading Practice Influence On The Value Of An Assigned Grade, Carrie Bala

All Graduate Plan B and other Reports

This article presents results of a study of grading practice influence on the value of an assigned grade. The value of an assigned grade, as an indication of student achievement of learning goals, was measured using the Utah Criterion-Referenced Test (CRT) in the subjects of Geometry and Algebra 2. The grading policies of six mathematics teachers at the same high school were categorized according to grading practice and their combined 587 students' scores on the Utah CRT were collected and analyzed. The findings suggest that certain grading practices , such as the use of a 1-4 scale and a criterion-referenced grading ...


Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff 2010 Portland State University

Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff

Dissertations and Theses

The work presented here represents a number of independent studies that investigated various components of the CH4 budget, namely the sources and sinks. We used a chemical-tracer model and created unique long-term time series of atmospheric CH4, carbon monoxide (CO), molecular hydrogen (H2), and methylchloroform (CH3CCl3) measurements at marine background air to derive histories of atmospheric hydroxyl radical (OH) - the main chemical oxidant of CH4, biomass burning - an important source of CH4 in the tropics, and emissions of CH4 from rice paddies - one of the largest anthropogenic sources of CH4 ...


The Local Structure Of Transition Metal Doped Semiconducting Boron Carbides, Jing Liu, Guangfu Luo, Wai-Ning Mei, Orhan Kizilkaya, Eric D. Shepherd, Jennifer I. Brand, Peter A. Dowben 2010 University of Nebraska-Lincoln

The Local Structure Of Transition Metal Doped Semiconducting Boron Carbides, Jing Liu, Guangfu Luo, Wai-Ning Mei, Orhan Kizilkaya, Eric D. Shepherd, Jennifer I. Brand, Peter A. Dowben

Peter Dowben Publications

Transition metal doped boron carbides produced by plasma enhanced chemical vapour deposition of orthocarborane (closo-1,2-C2B10H12) and 3d metal metallocenes were investigated by performing K-edge extended x-ray absorption fine structure and x-ray absorption near edge structure measurements. The 3d transition metal atom occupies one of the icosahedral boron or carbon atomic sites within the icosahedral cage. Good agreement was obtained between experiment and models for Mn, Fe and Co doping, based on the model structures of two adjoined vertex sharing carborane cages, each containing a transition metal. The local spin configurations of all the ...


Developing The Techniques For Raman, Surface-Enhanced Raman Scattering (Sers), And Fluorescence Spectroscopies Of Organic Molecules In Isolation, Jonathan Wolfe 2010 University of Mississippi. Sally McDonnell Barksdale Honors College

Developing The Techniques For Raman, Surface-Enhanced Raman Scattering (Sers), And Fluorescence Spectroscopies Of Organic Molecules In Isolation, Jonathan Wolfe

Honors Theses

The nature of matter and light has been a subject of philosophical debate since antiquity. However, by the end of the nineteenth century, much of the scientific community believed that most of the significant principles that govern the natural world had been discovered. Classical physics was able to explain complex phenomena such as planetary motions, elasticity, and hydrodynamics. The field of thermodynamics had been developed nearly to completion by James Joule, Sadi Carnot, Josiah Gibbs, et al. The magnetic and electronic nature of light had been demonstrated by James Clerk Maxwell's famous equations. In the neighboring field of chemistry ...


Magnetic And Optical Properties Of Multiferroic Gdmno3 Nanoparticles, X. L. Wang, D. Li, T. Y. Cui, Parashu Kharel, W. Liu, Z. D. Zhang 2010 Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, People’s Republic of China

Magnetic And Optical Properties Of Multiferroic Gdmno3 Nanoparticles, X. L. Wang, D. Li, T. Y. Cui, Parashu Kharel, W. Liu, Z. D. Zhang

Faculty Publications, Department of Physics and Astronomy

The magnetic and optical properties of multiferroic GdMnO3 nanoparticles synthesized by a polymerized complex method have been investigated. The GdMnO3 nanoparticles crystallized in orthorhombic perovskite-type structure. The zero-field-cooled and field-cooled magnetizations show that complicated magnetic transitions occur in a temperature range from 2 to 60 K, which were confirmed by magnetic hysteresis loops. Three shoulder absorption peaks centered at about 2.0, 2.3, and 2.7 eV are attributed to the Mn (3d)-electronic transitions, while an absorption peak at around 4.1 eV corresponds to the charge-transfer transitions between O (2p) and Mn (3d) states. UV ...


Generalized Curvilinear Advection Formalism For Finite Volume Codes Doing Relativistic Hydrodynamics, Jay Michael Call 2010 Louisiana State University and Agricultural and Mechanical College

Generalized Curvilinear Advection Formalism For Finite Volume Codes Doing Relativistic Hydrodynamics, Jay Michael Call

LSU Doctoral Dissertations

While it is possible to numerically evolve the relativistic fluid equations using any chosen coordinate mesh, typically there are distinct computational advantages associated with different types of candidate grids. For example, astrophysical flows that are governed by rotation tend to give rise to advection variables that are naturally conserved when a cylindrical mesh is used. On the other hand, Cartesian-like coordinates afford a more straightforward implementation of adaptive mesh refinement (AMR) and avoid the appearance of coordinate singularities. Here it is shown that it should be possible to reap the benefits associated with multiple types of coordinate systems simultaneously in ...


Fabrication Of Receptor-Modified Microfluidic Surfaces For Applications In Glycoprotein Screening, Jennifer Macalindong De Guzman 2010 Louisiana State University and Agricultural and Mechanical College

Fabrication Of Receptor-Modified Microfluidic Surfaces For Applications In Glycoprotein Screening, Jennifer Macalindong De Guzman

LSU Doctoral Dissertations

Glycoproteins have long been identified to have a profound association with human pathological processes, and they are much sought after as potential biomarkers to aid in the early diagnosis and clinical prognosis of cancers and diseases. There is currently high demand for high-throughput and low–limit–of–detection techniques that can afford profiling of the glycoproteome. Micro-total analysis systems (µTAS) based on microfluidics have the potential to fulfill these requirements, but in order to reduce the complexity of the protein pool, the µTAS devices must contain a pre-isolation and enrichment component. The research project undertaken here involved derivatization ...


Highly Efficient Selection, Enumeration, Enrichment, And Molecular Profiling Of Low-Abundance Biological Cells, Udara R. Dharmasiri Rasika Dharmasiri 2010 Louisiana State University and Agricultural and Mechanical College

Highly Efficient Selection, Enumeration, Enrichment, And Molecular Profiling Of Low-Abundance Biological Cells, Udara R. Dharmasiri Rasika Dharmasiri

LSU Doctoral Dissertations

After brief overviews of low-abundance cell selection techniques in chapter 1 and circulating tumor cells in chapter 2, this dissertation initially focuses on the development of aptamer incorporated high-throughput microfluidic techniques to select rare circulation prostate cancer cells (LNCaP) directly from whole blood with subsequent quantification of these rare cells using a non-labeling approach. Then, I extended the technology to environmental samples in an effort around time, sensitivity, and portability of traditional groundwater assessment. As a model bio- pathogen, E. coli O157:H7 was chosen due to its toxicity and its adverse impact on recreational waters. Low-abundance (<100 cells mL-1) E. coli O157:H7 cells were isolated and enriched from environmental water samples using a microfluidic chip that its capture beds were covalently decorated with E.coli O157:H7 specific polyclonal antibodies. The selected cells were enumerated using RT-qPCR technique. Finally, I have integrated HTMSU with electrokinetic enrichment microfluidic unit for performance of single recombinant low-abundance CTC cell-based assay. A series of analytical processes were carried out, including immunoaffinity selection of rare CTCs, quantification of selected cells via conductivity impedance and electrophoretic enrichment of selected cells for PCR/LDR/CE interrogation for detection of low-abundance point mutations in genomic DNA.


Model Based Analysis Of Some High Speed Network Issues, Suman Kumar 2010 Louisiana State University and Agricultural and Mechanical College

Model Based Analysis Of Some High Speed Network Issues, Suman Kumar

LSU Doctoral Dissertations

The study of complex problems in science and engineering today typically involves large scale data, huge number of large-scale scientific breakthroughs critically depends on large multi-disciplinary and geographically-dispersed research teams, where the high speed network becomes the integral part. To serve the ongoing bandwidth requirement and scalability of these networks, there has been a continuous evolution of different TCPs for high speed networks. Testing these protocols on a real network would be expensive, time consuming and more over not easily available to the researchers worldwide. Network simulation is well accepted and widely used method for performance evaluation, it is well ...


Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel 2010 Louisiana State University and Agricultural and Mechanical College

Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel

LSU Doctoral Dissertations

The Laser Interferometer Gravitational wave Observatory (LIGO) is network of three, power recycled Fabry-Perot Michelson interferometers built to detect gravitational waves from astrophysical sources at frequencies between 40 and 6000 Hz. For their fifth science run, from 2005 to 2007, the detectors observed at designed sensitivity, achieving equivalent strain amplitude noise of 3x10^−23 strain/rtHz at 100 Hz. To date, the observatory has not detected gravitational waves. However, even at such sensitivity, the expected detection rate for known astrophysical sources of gravitational waves is likely 0.02 yr^−1. The fundamental noise source of these ground-based detectors limiting the ...


Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains, Richard Charles Barnard 2010 Louisiana State University and Agricultural and Mechanical College

Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains, Richard Charles Barnard

LSU Doctoral Dissertations

This thesis studies optimal control problems on stratified domains. We first establish a known proximal Hamilton-Jacobi characterization of the value function for problems with Lipschitz dynamics. This background gives the motivation for our results for systems over stratified domains, which is a system with non-Lipschitz dynamics that were introduced by Bressan and Hong. We provide an example that shows their attempt to derive a Hamilton-Jacobi characterization of the value function is incorrect, and discuss the nature of their error. A new construction of a multifunction is introduced that possesses properties similar to those of a Lipschitz multifunction, and is used ...


The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham 2010 Louisiana State University and Agricultural and Mechanical College

The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham

LSU Doctoral Dissertations

Current classification approaches usually do not try to achieve a balance between fitting and generalization when they infer models from training data. Such approaches ignore the possibility of different penalty costs for the false-positive, false-negative, and unclassifiable types. Thus, their performances may not be optimal or may even be coincidental. This dissertation analyzes the above issues in depth. It also proposes two new approaches called the Homogeneity-Based Algorithm (HBA) and the Convexity-Based Algorithm (CBA) to address these issues. These new approaches aim at optimally balancing the data fitting and generalization behaviors of models when some traditional classification approaches are used ...


Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle 2010 Louisiana State University and Agricultural and Mechanical College

Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle

LSU Doctoral Dissertations

active compounds (PhACs) have been detected in the aquatic environment as a result of loading from various sources. In Louisiana, USA, many municipalities treat wastewater using natural systems, such as lagoons and wetlands, rather than using conventional wastewater treatment technologies and may discharge PhACs into the environment. These treatment systems are not designed to remove PhACs from wastewater, nor is it currently a regulatory requirement. Research on the fate of PhACs in the environment is needed to understand impacts on Louisiana’s important coastal system. Wastewater sampling for PhACs at the Mandeville, LA wastewater treatment plant (WWTP) determined that this ...


Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez 2010 Louisiana State University and Agricultural and Mechanical College

Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez

LSU Doctoral Dissertations

This dissertation is concerned with properties of local fields inside composites made from two materials with different power law behavior. This simple constitutive model is frequently used to describe several phenomena ranging from plasticity to optical nonlinearities in dielectric media. We provide the corrector theory for the strong approximation of fields inside composites made from two power law materials with different exponents. The correctors are used to develop bounds on the local singularity strength for gradient fields inside microstructured media. The bounds are multiscale in nature and can be used to measure the amplification of applied macroscopic fields by the ...


The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim de Mutsert 2010 Louisiana State University and Agricultural and Mechanical College

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the ...


Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda 2010 Louisiana State University and Agricultural and Mechanical College

Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda

LSU Doctoral Dissertations

Spatial and temporal patterns of mangrove vegetation in the Florida Coastal Everglades (FCE) reflect a major interplay of resources, regulators and hydroperiod gradients. I investigated landscape patterns of community structure, biomass and NPP of mangroves along two FCE estuaries: Shark River and Taylor River. I also evaluated whether pulsing events such as Hurricane Wilma are significant to soil nutrient inventories and vertical accretion of mangroves in FCE. There was a higher forest structural complexity of mangroves in Shark River relative to Taylor River. The biomass root:shoot ratio was 17 times higher in Taylor River relative to Shark River, indicating ...


Power Series Expansions For Waves In High-Contrast Plasmonic Crystals, Santiago Prado Parentes Fortes 2010 Louisiana State University and Agricultural and Mechanical College

Power Series Expansions For Waves In High-Contrast Plasmonic Crystals, Santiago Prado Parentes Fortes

LSU Doctoral Dissertations

In this thesis, a method is developed for obtaining convergent power series expansions for dispersion relations in two-dimensional periodic media with frequency dependent constitutive relations. The method is based on high-contrast expansions in the parameter _x0011_ = 2_x0019_d=_x0015_, where d is the period of the crystal cell and _x0015_ is the wavelength. The radii of convergence obtained are not too small, on the order of _x0011_ _x0019_ 10􀀀2. That the method applies to frequency dependent media is an important fact, since the majority of the methods available in the literature are restricted to frequency independent constitutive relations. The convergent ...


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