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Ferromagnetism And Transport In Diluted Magnetic Semiconductors, Abdolmadjid Nili 2010 Louisiana State University and Agricultural and Mechanical College

Ferromagnetism And Transport In Diluted Magnetic Semiconductors, Abdolmadjid Nili

LSU Doctoral Dissertations

This dissertation focuses on the study of ferromagnetism in Dilute Magnetic Semiconductors. To study these strongly correlated electronic systems, two non- perturbative techniques are used: the Dynamical Mean Field Approximation (DMFA) and the Dynamical Cluster Approximation (DCA). The model used for Dilute Magnetic Semiconductors (DMS) incorporates the strong spin-orbit couplings of the carrier holes as found in most III-V semiconductors doped with manganese such as Ga1-xMnxAs. Calculated within the DMFA, the spin-orbit coupling effects give rise to various interesting physics, primarily the anisotropic behavior of the impurity band that affect the charge transport properties in the ...


New Age Control On A Mid-Shelf Grounding Event In Eastern Basin, Ross Sea, Amy Noelle Cone 2010 Louisiana State University and Agricultural and Mechanical College

New Age Control On A Mid-Shelf Grounding Event In Eastern Basin, Ross Sea, Amy Noelle Cone

LSU Master's Theses

It is widely accepted that the West Antarctic Ice Sheet (WAIS) was grounded at the continental shelf edge in Eastern Ross Sea during the Last Glacial Maximum (LGM), but the precise chronology is debated. Existing post-LGM ice retreat chronologies are considered suspect because nearly all have been developed using radiocarbon dating of acid-insoluble organics (AIO). Foraminifer tests yield more accurate radiocarbon dates than AIO because unlike loose sediment, foram tests are unlikely to be contaminated by allochthonous carbon, but unfortunately forams are sparse in Antarctic marine sediment cores. Here I utilized a new 3-D multibeam survey of a mid-continental-shelf grounding ...


Subgroups Of The Torelli Group, Leah R. Childers 2010 Louisiana State University and Agricultural and Mechanical College

Subgroups Of The Torelli Group, Leah R. Childers

LSU Doctoral Dissertations

Let Mod(Sg) be the mapping class group of an orientable surface of genus g, Sg. The action of Mod(Sg) on the homology of Sg induces the well-known symplectic representation:

Mod(Sg) ---> Sp(2g, Z).
The kernel of this representation is called the Torelli group, I(Sg).

We will study two subgroups of I(Sg). First we will look at the subgroup generated by all SIP-maps, SIP(Sg). We will show SIP(Sg) is not I(Sg) and is in fact an infinite index subgroup of I(Sg). We will also classify which SIP-maps are in the kernel of ...


Modeling The Noble Metal/Tio2 (110) Interface With Hybrid Dft Functionals: A Periodic Electrostatic Embedded Cluster Model Study, Salai Cheettu Ammal, Andreas Heyden 2010 University of South Carolina - Columbia

Modeling The Noble Metal/Tio2 (110) Interface With Hybrid Dft Functionals: A Periodic Electrostatic Embedded Cluster Model Study, Salai Cheettu Ammal, Andreas Heyden

Faculty Publications

The interaction of Aun and Ptn (n=2,3) clusters with the stoichiometric and partially reduced rutile TiO2 (110) surfaces has been investigated using periodic slab and periodic electrostatic embedded cluster models. Compared to Au clusters, Pt clusters interact strongly with both stoichiometric and reduced TiO2 (110) surfaces and are able to enhance the reducibility of the TiO2 (110) surface, i.e., reduce the oxygen vacancy formation energy. The focus of this study is the effect of Hartree–Fock exchange on the description of the strength of chemical bonds at the interface of Au/Pt clusters and the TiO2 (110 ...


Dynamic Path Bifurcation For The Beckmann Reaction: Observation And Implication, H. Yamataka, M. Sato, H. Hasegawa, Salai Cheettu Ammal 2010 University of South Carolina - Columbia

Dynamic Path Bifurcation For The Beckmann Reaction: Observation And Implication, H. Yamataka, M. Sato, H. Hasegawa, Salai Cheettu Ammal

Faculty Publications

The reaction of oximes to amides, known as the Beckmann rearrangement, may undergo fragmentation to form carbocations + nitriles instead of amides when the cations have reasonable stability. The reactions of oxime derivatives of 1-substituted-phenyl-2-propanones and 3-substituted-phenyl-2-butanones in aqueous solvents gave both rearrangement and fragmentation products, the ratio of which was dependent on substituents. Transition state (TS) optimizations and intrinsic reaction coordinate (IRC) calculations for the reaction of 1-phenyl-2-propanone oximes showed that there is a single TS for each substituted compound. The IRC path from the TS either led to a rearrangement product or a fragmentation product depending on the substituent ...


Interannual Differences In Nutrient Dynamics During A Brown Tide Bloom (Aureococcus Anophagefferens) And The Interaction Of A. Anophagefferens With Heterotrophic Bacteria, George Eric Boneillo 2010 Old Dominion University

Interannual Differences In Nutrient Dynamics During A Brown Tide Bloom (Aureococcus Anophagefferens) And The Interaction Of A. Anophagefferens With Heterotrophic Bacteria, George Eric Boneillo

OEAS Theses and Dissertations

Blooms of Aureococcus anophagefferens (Brown Tides) in Chincoteague Bay were observed over a six-year period (2002–2007) during which interannual differences in nitrogen and carbon uptake and concentrations of dissolved constituents were compared at two sites, one in Maryland and the other in Virginia. Overall, I observed an increase in bloom intensity and duration over time. No single nitrogen compound was responsible for fueling blooms. Instead, A. anophagefferens demonstrated the ability to use a wide range of nitrogen compounds to meet its nutritional demands. Results show that NO3-, NH4+, urea, and DFAA were taken up simultaneously during blooms ...


Transmitter Optimization In Multiuser Wireless Systems With Quality Of Service Constraints, Danda B. Rawat 2010 Old Dominion University

Transmitter Optimization In Multiuser Wireless Systems With Quality Of Service Constraints, Danda B. Rawat

Electrical & Computer Engineering Theses & Disssertations

In this dissertation, transmitter adaptation for optimal resource allocation in wireless communication systems are investigated. First, a multiple access channel model is considered where many transmitters communicate with a single receiver. This scenario is a basic component of a. wireless network in which multiple users simultaneously access the resources of a wireless service provider. Adaptive algorithms for transmitter optimization to meet Quality-of-Service (QoS) requirements in a distributed manner are studied. Second, an interference channel model is considered where multiple interfering transmitter-receiver pairs co-exist such that a given transmitter communicates with its intended receiver in the presence of interference from other ...


Forensic Analysis Of A Playstation 3 Console, Scott Conrad, Greg Dorn, Philip Craiger 2010 University of Central Florida

Forensic Analysis Of A Playstation 3 Console, Scott Conrad, Greg Dorn, Philip Craiger

Publications

The Sony PlayStation 3 (PS3) is a powerful gaming console that supports Internet-related activities, local file storage and the playing of Blu-ray movies. The PS3 also allows users to partition and install a secondary operating system on the hard drive. This “desktop-like” functionality along with the encryption of the primary hard drive containing the gaming software raises significant issues related to the forensic analysis of PS3 systems. This paper discusses the PS3 architecture and behavior, and provides recommendations for conducting forensic investigations of PS3 systems.


Entropy And Information Causality In General Probabilistic Theories, Howard Barnum, Jonathan Barrett, Lisa Orloff Clark, Matthew S. Leifer, Robert Spekkens, Nicholas Stepanik, Alex Wilce, Robin Wilke 2010 Perimeter Institute for Theoretical Physics

Entropy And Information Causality In General Probabilistic Theories, Howard Barnum, Jonathan Barrett, Lisa Orloff Clark, Matthew S. Leifer, Robert Spekkens, Nicholas Stepanik, Alex Wilce, Robin Wilke

Mathematics, Physics, and Computer Science Faculty Articles and Research

We investigate the concept of entropy in probabilistic theories more general than quantum mechanics, with particular reference to the notion of information causality (IC) recently proposed by Pawlowski et al (2009 arXiv:0905.2292). We consider two entropic quantities, which we term measurement and mixing entropy. In the context of classical and quantum theory, these coincide, being given by the Shannon and von Neumann entropies, respectively; in general, however, they are very different. In particular, while measurement entropy is easily seen to be concave, mixing entropy need not be. In fact, as we show, mixing entropy is not concave whenever ...


Upper Limits On A Possible Gluon Mass, Shmuel Nussinov, Robert Shrock 2010 Chapman University

Upper Limits On A Possible Gluon Mass, Shmuel Nussinov, Robert Shrock

Mathematics, Physics, and Computer Science Faculty Articles and Research

We analyze upper limits on a possible gluon mass, mg. We first discuss various ways to modify quantum chromodynamics to include m(g) not equal 0, including a bare mass, a Higgs mechanism, and dynamical breaking of color SU(3)(c). From an examination of experimental data, we infer an upper limit m(g) < O(1) MeV. As part of our analysis, we show that a claim, hitherto unrefuted in the literature, of a much stronger upper limit on m(g), is invalid. We discuss subtleties in interpreting gluon mass limits in view of the fact that at scales below Lambda(QCD), quantum chromodynamics is strongly coupled, perturbation theory is not reliable, and the physics is not accurately described in terms of the Lagrangian degrees of freedom, including gluons. We also point out a fundamental difference in the behavior of quantum chromodynamics with a nonzero gluon mass and a weakly coupled gauge theory with a gauge boson mass.


Modeling Decision Making Related To Incident Delays During Hurricane Evacuations, Robert Michael Robinson 2010 Old Dominion University

Modeling Decision Making Related To Incident Delays During Hurricane Evacuations, Robert Michael Robinson

Computational Modeling and Simulation Engineering Theses & Dissertations

Successful evacuations from metropolitan areas require optimizing the transportation network, monitoring conditions, and adapting to changes. Evacuation plans seek to maximize the city's ability to evacuate traffic to flee the endangered region, but once an evacuation begins, real time events degrade even the best plans.

To better understand behavioral responses made during a hurricane evacuation, a survey of potential evacuees obtained data on demographics, driving characteristics, and the traffic information considered prior to and during an evacuation. Analysis showed significant levels of correlation between demographic factors (e.g., gender, age, social class, etc.) and self-assessed driver characteristics, but limited ...


Analysis Of Models For Longitudinal And Clustered Binary Data, Weiming Yang 2010 Old Dominion University

Analysis Of Models For Longitudinal And Clustered Binary Data, Weiming Yang

Mathematics & Statistics Theses & Dissertations

This dissertation deals with modeling and statistical analysis of longitudinal and clustered binary data. Such data consists of observations on a dichotomous response variable generated from multiple time or cluster points, that exhibit either decaying correlation or equi-correlated dependence. The current literature addresses modeling the dependence using an appropriate correlation structure, but ignores the feasible bounds on the correlation parameter imposed by the marginal means.

The first part of this dissertation deals with two multivariate probability models, the first order Markov chain model and the multivariate probit model, that adhere to the feasible bounds on the correlation. For both the ...


Concentrations, Distributions And Chemical Speciation Of Zinc And Cadmium In The Equatorial And South Atlantic Ocean, Gonzalo G. Carrasco 2010 Old Dominion University

Concentrations, Distributions And Chemical Speciation Of Zinc And Cadmium In The Equatorial And South Atlantic Ocean, Gonzalo G. Carrasco

OEAS Theses and Dissertations

Certain trace metals are important cofactors in enzymatic systems and are thus, essential for life in the world's oceans. Two of these metals, Zn and Cd, are required by phytoplankton for enzymes that facilitate carbon uptake (Morel and Price, 2003). In seawater the total dissolved concentration of a metal (MTD) is distributed among different chemical species and this chemical speciation dictates a metal's bioavailability. Strong organic metal-binding ligands greatly affect the metal's chemical speciation in the ocean, potentially limiting phytoplankton growth by reducing the concentrations of Zn2+ and Cd2+, the bioavailable forms of these two ...


Mathematical Models And Stability Analysis Of Cholera Dynamics, Shu Liao 2010 Old Dominion University

Mathematical Models And Stability Analysis Of Cholera Dynamics, Shu Liao

Mathematics & Statistics Theses & Dissertations

In this dissertation, we present a careful mathematical study of several epidemic cholera models, including the model of Codeco [11] in 2001, that of Hartley, Morris and Smith [22] in 2006, and that of Mukandavire, Liao, Wang and Gaff et al. [60] in 2010. We formally derive the basic reproduction number R0 for each model by computing the spectral radius of the next generation matrix. We focus our attention on the stability analysis at the disease-free equilibrium which determines the short-term epidemic behavior, and the endemic equilibrium which determines the long-term disease dynamics. Particularly, we incorporate the Volterra-Lyapunov matrix ...


Trace Metal Biogeochemistry In The Western North Pacific, Peter Lynn Morton 2010 Old Dominion University

Trace Metal Biogeochemistry In The Western North Pacific, Peter Lynn Morton

OEAS Theses and Dissertations

Dissolved and suspended particulate samples collected during the Intergovernmental Oceanographic Commission 2002 Contaminant Baseline Survey were analyzed to determine the surface and vertical distributions of Cd, Co, Cu, Mn, Ni Zn and Pb across the western and central North Pacific.

Dissolved trace metal concentrations were measured using a novel isotope dilution-ICP-MS method after extraction over an 8-hydroxyquinoline resin column and validated through the use of the SAFe consensus reference materials. Filtered suspended particulate matter was digested using an HCl/HNO3/HF mixture and analyzed by HR-ICP-MS to obtain total particulate concentrations for the trace metals and other tracer elements such ...


Canonical Correlation Analysis For Longitudinal Data, Raymond McCollum 2010 Old Dominion University

Canonical Correlation Analysis For Longitudinal Data, Raymond Mccollum

Mathematics & Statistics Theses & Dissertations

Data (multivariate data) on two sets of vectors commonly occur in applications. Statistical analysis of these data is usually done using a canonical correlation analysis (CCA). Occurrence of these data at multiple occasions or conditions leads to longitudinal multivariate data for a CCA. We address the problem of canonical correlation analysis on longitudinal data when the data have a Kronecker product covariance structure. Using structured correlation matrices we model the dependency of repeatedly observed data. Recent work of Srivastava, Nahtman, and von Rosen (2008) developed an iterative algorithm to determine the maximum likelihood estimate of the Kronecker product covariance structure ...


Book Review: Digital Forensic Evidence Examination, Gary C. Kessler 2010 Gary Kessler Associates

Book Review: Digital Forensic Evidence Examination, Gary C. Kessler

Publications

This document is Dr. Kessler's review of the second edition of Digital Forensic Evidence Examination by Fred Cohen. ASP Press, 2010. ISBN: 978-1-878109-45-3


Nanoporous High Surface Area Silicas With Chelating Groups For Heavy Metal Ion Adsorption From Aqueous Solution, Kothalawalage Nuwan Kothalawala 2010 Eastern Illinois University

Nanoporous High Surface Area Silicas With Chelating Groups For Heavy Metal Ion Adsorption From Aqueous Solution, Kothalawalage Nuwan Kothalawala

Masters Theses

No abstract provided.


Stratovolcano Growth By Co-Eruptive Intrusion: The 2008 Eruption Of Tungurahua Ecuador, J. Biggs, P. Mothes, M. Ruiz, F. Amelung, Timothy H. Dixon, S. Baker, S-H. Hong 2010 University of Oxford

Stratovolcano Growth By Co-Eruptive Intrusion: The 2008 Eruption Of Tungurahua Ecuador, J. Biggs, P. Mothes, M. Ruiz, F. Amelung, Timothy H. Dixon, S. Baker, S-H. Hong

School of Geosciences Faculty and Staff Publications

Volcanic edifices are constructed by a combination of erupted material and internal growth. We use the L-band satellite ALOS to produce InSAR measurements at Tungurahua Volcano, Ecuador. We find a maximum of 17.5 cm of uplift on the upper western flank between December 2007 and March 2008, coincident with an eruption in February 2008. The deformation can be modeled using an ellipsoidal or sill-like source within the edifice. The models require an elongated aspect ratio with a length of 4–6 km. The intruded volume of 1.2 × 106 m3 is roughly equivalent to the bulk erupted ...


Mined-Over Matter, Judy McIlrath 2010 University of South Florida

Mined-Over Matter, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

No abstract provided.


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