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Investigation Of The Interactions Of Cationic Polyelectrolytes With Anionic Surfactants: Effects Of Polymer, Surfactant And Solution Properties, Lisa Renee Huisinga

Dissertations

The intent of this research is to explore and understand the effects that a range of polymer, surfactant and solution parameters have on the interaction of oppositely-charged polymers and surfactants. Cationic polysaccharides were chosen for this research because they are known to interact with anionic surfactants, and they offer a wide range of adjustable polymer properties, including molecular weight, charge substitution, and backbone structure. Cationic poly(vinylpyridinium hydrochloride) polymers were chosen for these studies because they provide the opportunity to explore the effects of charge position on the interaction of cationic polymers with anionic surfactants and how this influences the mechanism …

Examination Of An Aloe Vera Galacturonate Polysaccharide Capable Of In Situ Gelation For The Controlled Release Of Protein Therapeutics, Shawn David Mcconaughy

Dissertations

A therapeutic delivery platform has been investigated with the ultimate goal of designing a sustained protein release matrix utilizing an in-situ gelling, acidic polysaccharide derived from the Aloe vera plant. The Aloe vera polysaccharide (AvP) has been examined in order to determine how chemical composition, structure, molecular weight and solution behavior affect gelation and protein/peptide delivery. Correlations are drawn between structural characteristics and solution behavior in order to determine the impact of polymer conformation and solvation on gel formation under conditions designed to simulate nasal applications. Steady state and dynamic rheology, classic and dynamic light scattering, zeta potential, pulse field …

Dispersion States And Surface Characteristics Of Physically Blended Polyhedral Oligomeric Silsesquioxane/Polymer Hybrid Nanocomposites, Rahul Misra

Dissertations

Control of dispersion and segregation states of nanostructured additives is one of the biggest challenges in realizing the optimum potential of high-performance hybrid polymer nanocomposites. Polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals, with their hybrid organic-inorganic nature and flexible functionalization with a variety of organic substituents, yield possibilities to control dispersion and tune compatibility in a wide range of polymer systems. The overall goal of this research is to investigate the fundamental parameters that influence the dispersion and segregation states of POSS nanostructured chemicals and to understand chain dynamics and conformations in physically blended POSS hybrid polymer nanocomposites (HPNC's). Multiple structural …

Synthesis, Propagation Kinetics, And Characterization Of D,L-Lactide-Based Polyols And Polyurethanes Therefrom, Scott Joseph Moravek

Dissertations

In order to expand the usefulness of degradable polyesters, degradable polyurethanes were synthesized using a mixed polyol system including poly(D,L-lactideco- glycolide) (PLGA), a well-known degradable polyester. Two isocyanate systems, methyl 2,6-diisocyantocaproate (LDI) and dicyclohexylmethane-4,4'- diisocyanate(Hi2MDI), were studied in order to achieve optimal physical and thermal properties of the thermoplastic polyurethane (TPU) while maintaining degradablity. The LDI based systems had excellent physical properties as well as thermal properties that may make them suitable for biomedical devices. The H12MDI based TPUs also had excellent physical properties as well as a higher melting temperature. The aforementioned TPUs were synthesized in small batches. Another …

Homotopy Perturbation Method And Padé Approximants For Solving Flierl-Petviashivili Equation, Syed T. Mohynd-Din, Muhammad A. Noor

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we present a reliable combination of homotopy perturbation method and Padé approximants to investigate the Flierl-Petviashivili (FP) equation. The approach introduces a new transformation necessary for the conversion of the Flierl-Petviashivili equation to a first order initial value problem and a reliable framework designed to overcome the difficulty of the singular point at x = 0. The proposed homotopy perturbation method is applied to the reformulated first order initial value problem which leads the solution in terms of transformed variable. The desired series solution is obtained by making use of the inverse transformation. The suggested algorithm may …

Partial Automorphism Semigroups, Jennifer Chubb, Valentina Harizanov, Andrei Morozov, Sarah Pingrey, Eric Ufferman

Mathematics

We study the relationship between algebraic structures and their inverse semigroups of partial automorphisms. We consider a variety of classes of natural structures including equivalence structures, orderings, Boolean algebras, and relatively complemented distributive lattices. For certain subsemigroups of these inverse semigroups, isomorphism (elementary equivalence) of the subsemigroups yields isomorphism (elementary equivalence) of the underlying structures. We also prove that for some classes of computable structures, we can reconstruct a computable structure, up to computable isomorphism, from the isomorphism type of its inverse semigroup of computable partial automorphisms.

Fisheries Research Report No. 182 - A Likelihood Analysis Of Non-Indigenous Marine Species Introduction To Fifteen Ports In Western Australia, Justin I. Mcdonald

Fisheries Research Reports

As an island continent, Australia is heavily dependent upon maritime transport with over 95% of its imports and exports transported by ship (Australian State of the Environment Committee, 2001). With about one third of Australia’s coastline, Western Australia ranks fourth of the six states and territory in the number of known non-indigenous marine species.

In this study fifteen ports in Western Australia were assessed on the potential for non-indigenous marine species to become introduced through ballast water and biofouling. The overall vesselmediated incursion risk to Western Australian ports was calculated by summing the relative incursion threat posed by visits to …

Three-Dimensional Microfluidic Devices Fabricated In Layered Paper And Tape, Andres W. Martinez, Scott T. Phillips, George M. Whitesides

Chemistry and Biochemistry

This article describes a method for fabricating 3D microfluidic devices by stacking layers of patterned paper and double-sided adhesive tape. Paper-based 3D microfluidic devices have capabilities in microfluidics that are difficult to achieve using conventional open-channel microsystems made from glass or polymers. In particular, 3D paper-based devices wick fluids and distribute microliter volumes of samples from single inlet points into arrays of detection zones (with numbers up to thousands). This capability makes it possible to carry out a range of new analytical protocols simply and inexpensively (all on a piece of paper) without external pumps. We demonstrate a prototype 3D …

The Application Of Electrical Resistivity And Microgravity To Locate Tunnels Along The U.S.-Mexico Border At Calexico, Gina Lee Cesin

Masters Theses & Specialist Projects

No abstract provided.

Water Quality Impacts From Agricultural Land-Use In The Karst Groundwater Basin Of Qingmuguan, Chongqing, China, Ted W. Baker

Masters Theses & Specialist Projects

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into fluvial systems travelling through the subsurface in karst areas are often very similar to the concentrations arriving at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be …

Atrazine Contamination And Suspended Sediment Transport Within Logsdon River, Mammoth Cave, Kentucky, Julie Eileen Schenck Brown

Masters Theses & Specialist Projects

Understanding the potential for karst aquifer contamination by sediment-sorbed pesticides is important for cave conservation efforts in agricultural landscapes. Flow rate, water quality parameters and suspended sediment concentrations were measured in Logsdon River, a ~10km karst conduit within the Turnhole Spring Groundwater Basin of Mammoth Cave National Park to determine characteristics of storm-period transport of sediment-sorbed atrazine through a conduit-flow karst aquifer.

Analysis of two independent precipitation events occurring in the Spring of 2008 from May 2-4 and May 27-29 demonstrated the rapid response of the Logsdon River to precipitation events with detections of atrazine increasing during the initial turbidity …

Numerical Modeling Of A Stenosed Artery Using Mathematical Model Of Variable Shape, S. Mukhopadhyay, G. C. Layek

Applications and Applied Mathematics: An International Journal (AAM)

The intention of the present work is to carry out a systematic analysis of flow behavior in a two-dimensional tube (modeled as artery) with a locally variable shaped constrictions. The simulated artery, containing a viscous incompressible fluid representing the flowing blood, is treated to be complaint as well as rigid tube. The shape of the stenosis in the arterial lumen is chosen to be symmetric as well as asymmetric about the middle cross section perpendicular to the axis of the tube in order to improve resemblance to the in-vivo situation. The constricted tube is transformed into a straight tube and …

Steganography In Ipv6, Barret Miller

Computer Science and Computer Engineering Undergraduate Honors Theses

Steganography is the process of hiding a secret message within another message such that it is difficult to detect the presence of the secret message. In other words, the existence of the secret message is hidden. A covert channel refers to the actual medium that is used to communicate the information such as a message, image, or file. This honors thesis uses steganography within the source address fields of Internet Protocol Version 6 (IPv6) packets to create a covert channel through which clandestine messages are passed from one party to another. A fully functional computer program was designed and written …

Direct Extraction Of Normal Mapped Meshes From Volume Data, Mark Barry, Zoë J. Wood

Computer Science and Software Engineering

We describe a method of directly extracting a simplified contour surface along with detailed normal maps from volume data in one fast and integrated process. A robust dual contouring algorithm is used for efficiently extracting a high-quality "crack-free" simplified surface from volume data. As each polygon is generated, the normal map is simultaneously generated. An underlying octree data structure reduces the search space required for high to low resolution surface normal mapping. The process quickly yields simplified meshes fitted with normal maps that accurately resemble their complex equivalents.

Watershed Condition Assessment For Little River Canyon National Preserve, Alabama, Nathan Demille Rinehart

Masters Theses & Specialist Projects

No abstract provided.

On A-Ary Subdivision For Curve Design Ii. 3-Point And 5-Point Interpolatory Schemes, Jian-Ao Lian

Applications and Applied Mathematics: An International Journal (AAM)

The a-ary 3-point and 5-point interpolatery subdivision schemes for curve design are introduced for arbitrary odd integer a greater than or equal to 3. These new schemes further extend the family of the classical 4- and 6-point interpolatory schemes.

Simulation Modeling Of Karst Aquifer Conduit Evolution And Relations To Climate, John D. Broome

Masters Theses & Specialist Projects

ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of conduit growth than climates with more uniform precipitation distributions. To study this concept, a computer program “Cave Growth” was developed that modeled the growth of a cross-section of a cave passage under dynamic flow and chemical conditions. A series of 46 simulation datasets were created to represent different climatic conditions. These simulations had the same total annual …

Calibrating Function Point Backfiring Conversion Ratios Using Neuro-Fuzzy Technique, Justin Wong, Luiz Fernando Capretz, Danny Ho

Electrical and Computer Engineering Publications

Software estimation is an important aspect in software development projects because poor estimations can lead to late delivery, cost overruns, and possibly project failure. Backfiring is a popular technique for sizing and predicting the volume of source code by converting the function point metric into source lines of code mathematically using conversion ratios. While this technique is popular and useful, there is a high margin of error in backfiring. This research introduces a new method to reduce that margin of error. Neural networks and fuzzy logic in software prediction models have been demonstrated in the past to have improved performance …

Hydrochemistry Of Wetlands Along The Platte River Near Ashland, Nebraska, Carrie L. Wiese

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

A Performance And Productivity Study Using Mpi, Titanium, And Fortress, Amy Apon, Chris Bryan, Wesley Emeneker

Publications

The popularity of cluster computing has increased focus on usability, especially in the area of programmability. Languages and libraries that require explicit message passing have been the standard. New languages, designed for cluster computing, are coming to the forefront as a way to simplify parallel programming. Titanium and Fortress are examples of this new class of programming paradigms. This papers presents results from a productivity study of these two newcomers with MPI, the de- facto standard for parallel programming.

Growing Fields Of Interest: Using An Expand And Reduce Strategy For Domain Model Extraction, Christopher Thomas, Pankaj Mehra, Roger Brooks, Amit P. Sheth

Kno.e.sis Publications

Domain hierarchies are widely used as models underlying information retrieval tasks. Formal ontologies and taxonomies enrich such hierarchies further with properties and relationships associated with concepts and categories but require manual effort; therefore they are costly to maintain, and often stale. Folksonomies and vocabularies lack rich category structure and are almost entirely devoid of properties and relationships. Classification and extraction require the coverage of vocabularies and the alterability of folksonomies and can largely benefit from category relationships and other properties. With Doozer, a program for building conceptual models of information domains, we want to bridge the gap between the vocabularies …

Determining Chemical Signatures Of Geologic Materials For Establishing Provenience Of Anasazi Red And Gray Wares Using Esem-Eds And Icp-Ms, Champagne Springs Ruins, Co, Steven Mathew Di Naso

All-Inclusive List of Electronic Theses and Dissertations

Compositional analyses of prehistoric ceramics and geological materials allow archaeologists to establish provenience of artifacts through comparative analysis of the materials used in prehistoric ceramic production. Where pottery clay pastes and tempering constituents originate from locally or regionally available geological materials, identifying their chemical composition and their geographic location and distribution facilitates a better understanding of the inter and intra socio-spatial and socioeconomic patterns among neighboring communities. The Champagne Springs Ruins were occupied during the late Pueblo I (A.D. 700 -A.D. 900) to early Pueblo II (A.D. 900 TO A.D. 1100) periods. The traditional view of local ceramic production from …

Magnetohydrodynamic Effects In Propagating Relativistic Jets: Reverse Shock And Magnetic Acceleration, Yosuke Mizuno, Bing Zhang, Bruno Giacomazzo, Ken-Ichi Nishikawa, Phillip E. Hardee, Shigehiro Nagataki, Dieter H. Hartmann

Publications

We solve the Riemann problem for the deceleration of an arbitrarily magne-tized relativistic flow injected into a static unmagnetized medium in one dimen-sion. We find that for the same initial Lorentz factor, the reverse shock becomes progressively weaker with increasing magnetization σ (the Poynting-to-kinetic energy flux ratio), and the shock becomes a rarefaction wave when σ exceeds a critical value, σc, defined by the balance between the magnetic pressure in the flow and the thermal pressure in the forward shock. In the rarefaction wave regime, we find that the rarefied region is accelerated to a Lorentz factor that is significantly …

A Model To Use Denied Internet Traffic To Indirectly Discover Internal Network Security Problems, Chet Langin, Hongbo Zhou, Shahram Rahimi

Department of Computer Science Faculty Scholarship and Creative Works

We propose a model for using firewall log entries of denied inbound Internet traffic for indirect discovery of local IP addresses that have security problems. This method is used successfully to discover two computers on the network of Southern Illinois University which were infected with malicious feral software, as well as two more IP addresses on the university network with other security problems.

A Reliable Approach For Higher-Order Integro-Differential Equations, Muhammad A. Noor, Syed T. Mohyud-Din

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we apply the variational iteration method (VIM) for solving higher-order integro differential equations by converting the problems into system of integral equations. The proposed technique is applied to the re-formulated system of integro-differential equations. Numerical results show the accuracy and efficiency of the suggested algorithm. The fact that the VIM solves nonlinear problems without calculating Adomian’s polynomials is a clear advantage of this technique over the decomposition method.

Scattering Of An Electromagnetic Plane Wave By A Luneburg Lens. I. Ray Theory, James A. Lock

Physics Faculty Publications

For a plane wave incident on either a Luneburg lens or a modified Luneburg lens, the magnitude and phase of the transmitted electric field are calculated as a function of the scattering angle in the context of ray theory. It is found that the ray trajectory and the scattered intensity are not uniformly convergent in the vicinity of edge ray incidence on a Luneburg lens, which corresponds to the semiclassical phenomenon of orbiting. In addition, it is found that rays transmitted through a large-focal-length modified Luneburg lens participate in a far-zone rainbow, the details of which are exactly analytically soluble …

Scattering Of An Electromagnetic Plane Wave By A Luneburg Lens. Ii. Wave Theory, James A. Lock

Physics Faculty Publications

The partial wave scattering and interior amplitudes for the interaction of an electromagnetic plane wave with a modified Luneburg lens are derived in terms of the exterior and interior radial functions of the scalar radiation potentials evaluated at the lens surface. A Debye series decomposition of these amplitudes is also performed and discussed. The effective potential inside the lens for the transverse electric polarization is qualitatively examined, and the approximate lens size parameters of morphology-dependent resonances are determined. Finally, the physical optics model is used to calculate wave scattering in the vicinity of the ray theory orbiting condition in order …

Scattering Of An Electromagnetic Plane Wave By A Luneburg Lens. Iii. Finely Stratified Sphere Model, James A. Lock

Physics Faculty Publications

The parallel iteration procedure for computing scattering by a multilayer sphere is described. The procedure uses a successive doubling strategy applied to four sets of multiple-scattering amplitudes, which is reminiscent of the fast Fourier transform (FFT) algorithm. The procedure is then used to calculate scattering of a plane wave by a modified Luneburg lens. The evolution of the transmission rainbow for the Luneburg lens parameter f > 1 into an orbiting ray for f = 1 and into a series of morphology-dependent resonances for f < 1 is studied, and various features of the scattered intensity as a function of scattering angle are commented on. It is found that some resonances are formed without the presence of an exterior centrifugal barrier to confine them. (C) 2008 Optical Society of America

Rainbows In The Grass. I. External Reflection Rainbows From Pendant Droplets, James A. Lock, Charles L. Adler, Richard W. Fleet

Physics Faculty Publications

In the mid-morning on a sunny day one can sometimes see glare spots associated with uncolored "rainbow" (i.e., fold) caustics due to the sunlight reflected from the surface of dew or guttation drops. We show that these dewdrop reflection rainbows are due to places on the droplet (i.e., from an "inflection circle") where its Gaussian curvature becomes zero. We work out the theory of such caustics with horizontally incident light and present a comparison of the theory to measurements made in the laboratory. (C) 2008 Optical Society of America