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2011

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Characterization And Prototyping Of The Rotating Modulator Hard X-Ray/Gamma-Ray Telescope, Brent Budden Jan 2011

Characterization And Prototyping Of The Rotating Modulator Hard X-Ray/Gamma-Ray Telescope, Brent Budden

LSU Doctoral Dissertations

A hard x-ray/gamma-ray telescope with high sensitivity and wide field of view would be capable of performing an all-sky census of black holes over a wide range of obscuration and accretion rates. As an example, NASA's Black Hole Finder Probe mission was designed to provide a 5-sigma flux sensitivity in a 1-year observation of ~0.02 mCrab in the 10 - 150 keV energy range and 0.5 mCrab in the 150 - 600 keV energy range with 3 - 5 minutes of arc angular resolution. These are significantly higher sensitivity and resolution goals than those of current instruments. The design focus …


On Greenberg's Question: An Algebraic And Computational Approach, David H. Chapman Jan 2011

On Greenberg's Question: An Algebraic And Computational Approach, David H. Chapman

LSU Doctoral Dissertations

Greenberg asked whether arithmetically equivalent number fields share the same Iwasawa invariants. In this dissertation it is shown that the problem naturally breaks up into four cases, depending on properties of Galois groups. This analysis is then used to give a positive answer to Greenberg’s question in some nontrivial examples.


Are Local Chemical Releases Causing An Increase In Cancer Rates In East Baton Rouge Parish?, India T. Anderson Jan 2011

Are Local Chemical Releases Causing An Increase In Cancer Rates In East Baton Rouge Parish?, India T. Anderson

LSU Master's Theses

Environmental pollution has become a steadily growing problem in today’s society. East Baton Rouge alone has 13 chemical plants in the parish. The goal of this research is to find out if the chemical releases in the parish are having an effect on the cancer rates in East Baton Rouge Parish. I gathered data from all 64 parishes in Louisiana. The four chemicals I chose to study specifically, Benzene, Dioxin, Formaldehyde, and Xylene. Chemical release data was taken from the Toxic Release Inventory (TRI) website and software from the years1988 to 2009, which was the last reporting year. The cancers …


Stochastic Modelling Of Eukaryotic Cell Cycle, Murali Krushna Koneru Jan 2011

Stochastic Modelling Of Eukaryotic Cell Cycle, Murali Krushna Koneru

LSU Master's Theses

Stochastic models are developed to capture the inherent stochasticity of the biochemical networks associated to many biological processes. The objective of the present thesis is to present a detailed picture of stochastic approach for the mathematical modeling of eukaryotic cell cycle, to demonstrate an important application of such model in chemotherapy and to present a methodology for selecting the model parameters. The stochastic cell cycle model, developed using stochastic chemical kinetics approach, leads to the formation of an infinite dimensional differential equation in probabilities of system being in a specific state. Using Monte Carlo simulations of this model, dynamics of …


Using X-Ray Computed Tomography To Quantify Damage Of Hot-Mix Asphalt In The Dynamic Complex Modulus And Flow Number Tests, Hao Ying Jan 2011

Using X-Ray Computed Tomography To Quantify Damage Of Hot-Mix Asphalt In The Dynamic Complex Modulus And Flow Number Tests, Hao Ying

LSU Master's Theses

The dynamic modulus test is conducted based on the assumption that no damage is induced during the testing process and that measurements are conducted within the linear viscoelastic region. In addition, significant damage is expected to occur during the flow number test process. While these assumptions are well-defined, the levels of damage taking place during these tests have not been quantified. The objectives of this study were to quantify the levels of damage in the dynamic complex modulus and flow number tests using x-ray computed tomography (CT) and to characterize the microstructural properties of asphalt mixtures under loading. Four Superpave …


An Analysis Of The Methodological And Human Error Within Momentary Time Sampling Data Collection, Joslyn Cynkus Mintz Jan 2011

An Analysis Of The Methodological And Human Error Within Momentary Time Sampling Data Collection, Joslyn Cynkus Mintz

LSU Doctoral Dissertations

Teachers often serve as data collectors for the problem behavior of referred students in their classrooms; yet, the accuracy of teacher data collection has rarely been directly assessed. Momentary time sampling (MTS) may be a potentially useful option for teacher data collection because it does not require continuous monitoring, but rather requires the teacher to score the occurrence or non-occurrence of targeted behaviors at given instances. Research has shown that the smaller the interval between observations, the less methodological error will be introduced into MTS. However, the use of short-interval windows requires additional effort on the part of the teacher, …


A Partial Order On Classical And Quantum States, Arka Bandyopadhyay Jan 2011

A Partial Order On Classical And Quantum States, Arka Bandyopadhyay

LSU Master's Theses

In this work we extend the work done by Bob Coecke and Keye Martin in their paper “Partial Order on Classical States and Quantum States (2003)”. We review basic notions involving elementary domain theory, the set of probability measures on a finite set {a1, a2, ..., an}, which we identify with the standard (n-1)-simplex ∆n and Shannon Entropy. We consider partial orders on ∆n, which have the Entropy Reversal Property (ERP) : elements lower in the order have higher (Shannon) entropy or equivalently less information . The ERP property is important because of its applications in quantum information theory. We …


Carbon Sequestration And Uneven-Aged Management Of Loblolly Pine Stands In The Southern Usa: A Joint Optimization Approach, Rajan Parajuli Jan 2011

Carbon Sequestration And Uneven-Aged Management Of Loblolly Pine Stands In The Southern Usa: A Joint Optimization Approach, Rajan Parajuli

LSU Master's Theses

Forest carbon sequestration is regarded as a viable and cost effective option for reducing global greenhouse gas emissions. Several research studies analyzed the effects of joint management of carbon and timber under different even-aged forest management scenarios, and concluded that carbon benefits can alter forest management schedules significantly. However, research specifically focused on the inclusion of carbon sequestration benefits into uneven-aged management has received little attention. This study determined the optimum joint management regime of timber and carbon in uneven-aged loblolly pine stands in Louisiana, and assessed management and financial effects resulting from the integration of carbon benefits into uneven-aged …


Oceanic Light Absorption Properties: Assessment And Characterization In The Southeastern Bering Sea Using Field And Satellite Observations, Puneeta Suresh Naik Jan 2011

Oceanic Light Absorption Properties: Assessment And Characterization In The Southeastern Bering Sea Using Field And Satellite Observations, Puneeta Suresh Naik

LSU Doctoral Dissertations

In recent decades the Bering Sea has been subjected to large climatic variability with cascading consequences on its productive marine ecosystem. Long-term as well as short-term monitoring is essential if we are to maintain its capability to supply the resources on which the national and local economy depend. Remote sensing together with in-situ and laboratory measurements of physical, biological and optical properties have considerable potential for monitoring and measuring the effects of climate-driven changes on this ecosystem. A major shortcoming to obtain accurate estimates of optically active components (such as colored dissolved organic matter, non-algal particulate matter, and phytoplankton) from …


A Comparative Study Of Cellulose I And Ii And Fibers And Nanocrystals, Yiying Yue Jan 2011

A Comparative Study Of Cellulose I And Ii And Fibers And Nanocrystals, Yiying Yue

LSU Master's Theses

The influence of sodium hydroxide treatment on the structure of cotton fibers was studied. Compared to raw cotton fibers, the entire bundles of mercerized fibers were converted into a swollen and roughened state. Fourier transform infrared spectrometry (FTIR) indicated that intermolecular hydrogen bonding was enhanced by mercerization treatment. Wide-angle X ray diffraction (WXRD) results showed decreased fiber crystallinity after mercerization. The structure of cellulose II fibers was more thermally stable than cellulose I fibers. Mechanical properties of cotton fiber-reinforced polyethylene oxide (PEO) composites demonstrated that both raw and mercerized cotton fibers enhanced their tensile strength of the PEO matrix, but …


Two-Particle Level Diagrammatic Approaches For Strongly Correlated Systems, Herbert Fotso Jan 2011

Two-Particle Level Diagrammatic Approaches For Strongly Correlated Systems, Herbert Fotso

LSU Doctoral Dissertations

This thesis presents the development of new numerical methods for the treatment of strongly correlated electron systems based on self-consistent approaches at both the one and the two-particle level such as the parquet formalism. The parquet formalism was solved for the first time on a two-dimensional cluster. When the fully irreducible vertex is approximated by the bare vertex, we obtain the parquet approximation. Its validity was investigated by comparing results that it produces to those of other conserving approximations such as the FLuctuation EXchange (FLEX) approximation or the Second Order Perturbation Theory (SOPT). We found that it provides a significant …


An Intelligent Othello Player Combining Machine Learning And Game Specific Heuristics, Kevin Anthony Cherry Jan 2011

An Intelligent Othello Player Combining Machine Learning And Game Specific Heuristics, Kevin Anthony Cherry

LSU Master's Theses

Artificial intelligence applications in board games have been around as early as the 1950's, and computer programs have been developed for games including Checkers, Chess, and Go with varying results. Although general game-tree search algorithms have been designed to work on games meeting certain requirements (e.g. zero-sum, two-player, perfect or imperfect information, etc.), the best results, however, come from combining these with specific knowledge of game strategies. In this MS thesis, we present an intelligent Othello game player that combines game-specific heuristics with machine learning techniques in move selection. Five game specific heuristics, namely corner detection, killer move detection, blocking, …


Spatial Ecology Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Louisiana Coastal Waters, Jody Lynn Callihan Jan 2011

Spatial Ecology Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Louisiana Coastal Waters, Jody Lynn Callihan

LSU Doctoral Dissertations

Spotted seatrout, Cynoscion nebulosus, are common in estuaries and coastal waters of the south Atlantic and Gulf of Mexico and are of considerable recreational and economic importance. Still, the spatial ecology of this species is under-studied and poorly resolved, especially in Louisiana waters. To address this important knowledge gap, I examined the movements, distribution, and habitat use of adult spotted seatrout in coastal Louisiana primarily using high-resolution acoustic telemetry and secondarily, conventional tagging (mark-recapture) data. At the largest spatial scale investigated, I found that adults exhibited a high degree of estuarine fidelity and rarely undertook large-scale movements in excess of …


Variability In Red Snapper Otolith Microchemistry Among Gulf Of Mexico Regions, Michelle Zapp Sluis Jan 2011

Variability In Red Snapper Otolith Microchemistry Among Gulf Of Mexico Regions, Michelle Zapp Sluis

LSU Doctoral Dissertations

Red snapper, Lutjanus campechanus, has been an economically important reef fish in the Gulf of Mexico (Gulf) for over 150 years and is currently overfished. Catch statistics and demographic differences have lead to the population being categorized into eastern and western substocks divided by the Mississippi River, but data is recombined to set a Gulf-wide annual catch limit. The two objectives of this study were to apply otolith nursery chemical signatures to estimate red snapper mixing dynamics in the western Gulf, and to determine if signatures based upon trace metals associated with oil and gas platforms could discriminate between region …


A Look At The Integration Of Wetlands And Hazard Mitigation Planning In Coastal Louisiana, Kathleen Melissa Bowers Jan 2011

A Look At The Integration Of Wetlands And Hazard Mitigation Planning In Coastal Louisiana, Kathleen Melissa Bowers

LSU Master's Theses

Due to the destruction of the damaging hurricanes of 2005, Katrina and Rita, more effort has gone into the rebuilding and prevention of future disasters along the Louisiana coast than ever before. This research focuses on the use of wetlands, in the ten coastal parishes of Louisiana, as a mitigation effort aiding in the protection of coastal communities. Using content analysis and decision support software, a wetland ranking was created that represents how wetlands are utilized and protected within each parish. Criteria gathered from the plans include how many times wetlands were mentioned, collaboration with the state and other agencies, …


Numerical Studies Of Flow In Porous Media Using An Unstructured Approach, Nathan Matthew Lane Jan 2011

Numerical Studies Of Flow In Porous Media Using An Unstructured Approach, Nathan Matthew Lane

LSU Doctoral Dissertations

Flow and transport in porous media is relevant to many areas of engineering and science including groundwater hydrology and the recovery of oil and gas. Porous materials are characterized by the unique shape and connectivity of the internal void structures which give rise to a large range in macroscopic transport properties. Historically an inability to accurately describe the internal pore-structure has prevented detailed study of the role of pore structure on transport. In recent decades however, the combination of high resolution imaging technologies with computational modeling has seen the development of fundamental pore-scale techniques for studying flow in porous media. …


Developing A Gulf-Wide Oyster Reef Restoration Plan: Identification Of Spatial, Socio-Economic And Geo-Political Constraints, Elizabeth Ashby Nix Jan 2011

Developing A Gulf-Wide Oyster Reef Restoration Plan: Identification Of Spatial, Socio-Economic And Geo-Political Constraints, Elizabeth Ashby Nix

LSU Master's Theses

Oyster reefs have recently been identified as one of the most endangered coastal ecosystems, fueling efforts to restore and enhance these systems. Oyster reefs located in the northern Gulf of Mexico have been identified as some of the healthiest of reefs globally, and current efforts focus on devising an approach to Gulf-wide restoration of these reefs. As with all natural resource management and restoration, success is dependent on more than simply understanding the biological requirements of the resource; rather, they are equally dependent on understanding and working within the social and political context in which these management and restoration activities …


Effects Of Row Spacing And Debris Distribution On Small Mammal And Vegetation Communities In Newly Established Loblolly Pine Plantations, Louisiana, Joshua Lee Grace Jan 2011

Effects Of Row Spacing And Debris Distribution On Small Mammal And Vegetation Communities In Newly Established Loblolly Pine Plantations, Louisiana, Joshua Lee Grace

LSU Master's Theses

Commercial pine (Pinus spp.) forests in the southeastern United States are key to providing fiber for global wood supply needs. Concern has arisen over possible effects of intensive forest management techniques, including row spacing and distribution of woody debris after logging, on plant and wildlife communities. Therefore, we quantified response of plant and small mammal communities in replanted loblolly pine (P. taeda) stands to mechanical site preparation including 2 levels of row spacing and 2 methods of distributing woody debris following harvest in north and southeastern Louisiana, USA. Sites (n=16) were prepared with a combination of row spacing between planting …


Analytical Design Method For Cold Production Of Heavy Oil With Bottom Water Using Bilateral Sink Wells, Wenting Qin Jan 2011

Analytical Design Method For Cold Production Of Heavy Oil With Bottom Water Using Bilateral Sink Wells, Wenting Qin

LSU Doctoral Dissertations

Few heavy oil reservoirs with strong bottom water drives have been developed successfully because of severe water coning. Water coning tends to cause low ultimate recovery, low well productivity, and high water production. Although thermal and gravity-assisted methods might improve recovery in oil reservoirs, such methods are widely perceived as either economically unfavorable or technologically infeasible. This study proposes a new, cold production technique, called Bilateral Water Sink (BWS), to meet those challenges. The BWS method suppresses water cresting by producing oil and water simultaneously from separate, horizontal wells completed in the oil and water zones; the oil and water …


The Influence Of Budget Allocation By Function On Student Retention Of Public Community Colleges In The Sixteen States In The Southern Region Education Board, Clayton Clendenin Burton Jan 2011

The Influence Of Budget Allocation By Function On Student Retention Of Public Community Colleges In The Sixteen States In The Southern Region Education Board, Clayton Clendenin Burton

LSU Doctoral Dissertations

Stakeholders of higher education expect a positive return for their investment. One of the measures of success for higher education is persistence; one of the measures of persistence is retention rate. One segment of higher education, community colleges, receives a significant outlay of public resources in terms of government appropriations, student financial aid, and individual investment. This study follows the framework of Ryan (2004) and Gansemer-Topf and Schuh (2006) who successfully created models using the allocation of financial resources to predict graduation and retention rates for four-year colleges. Using data from the U. S. Department of Education’s Integrated Postsecondary Education …


Expression, Identification, And Bioactivity Of Recombinant Human Erythropoietin From Lmh/2a (Leghorn Male Hepatoma)Cell Line, Amanda Cecile Broussard Jan 2011

Expression, Identification, And Bioactivity Of Recombinant Human Erythropoietin From Lmh/2a (Leghorn Male Hepatoma)Cell Line, Amanda Cecile Broussard

LSU Master's Theses

Erythropoietin (EPO) is the main cytokine regulator for red blood-cell production in the human by binding to erythropoietin receptors to promote erythroid proliferation, survival and differentiation. Administration of recombinant human EPO (rhEPO) as a therapeutic has been shown to improve renal and non-renal anemia and this success has led to a high medical global demand. Chinese hamster ovary (CHO) cells, yeast, and bacteria have been used to produce rhEPO but nevertheless there is still a need for a low-cost and high quality expression system for rhEPO. LMH/2A cells, as an alternative model, were transfected with the codon optimized human EPO …


Hurricane Induced Land And Vegetation Changes In The Breton Sound Estuary And Chandeleur Islands Using Landsat 5 Tm, Vandana Varshini Raghunathan Jan 2011

Hurricane Induced Land And Vegetation Changes In The Breton Sound Estuary And Chandeleur Islands Using Landsat 5 Tm, Vandana Varshini Raghunathan

LSU Master's Theses

This study focuses on hurricane-induced changes in land and vegetation primarily in two study areas, the Breton Sound Estuary and the Chandeleur Islands, southeast of New Orleans, Louisiana. Breton Sound Estuary consists of the Caernarvon Diversion, a fresh water diversion of the Mississippi River that supplies this region with managed pulses of fresh water and sediments. The Chandeleur Islands are a chain of barrier islands that are uninhabited and transgressive in nature. A sequence of hurricanes in the past two decades has greatly altered both areas significantly. Satellite data were analyzed for a period of 24 years (1987-2011) of Breton …


Experimental Study Of Cognitive Radio Test-Bed Using Usrp, Venkat Vinod Patcha Jan 2011

Experimental Study Of Cognitive Radio Test-Bed Using Usrp, Venkat Vinod Patcha

LSU Master's Theses

Cognitive Radio is an emerging technology that enables efficient utilization of the spectrum. As such, it has created great interests in industrial and research fields. Many people have proposed test-bed models for the performance analysis of primary and secondary users in a real-time noise environment. However, these test-beds are generally lacking in their range of capabilities as well as accurate implementation of the proposed models. In this thesis, we develop our test-bed on USRP to achieve the spectrum sensing and co-existence of primary and secondary users, while implementing the rendezvous protocols for secondary traffic coordination. We first demonstrate the spectrum …


A Gravitational Wave Observatory Operating Beyond The Quantum Shot-Noise Limit, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, C. Adams, R. Adhikari, C. Affeldt, P. Ajith, B. Allen, G. S. Allen, E. Amador Ceron, D. Amariutei, R. S. Amin, S. B. Anderson, W. G. Anderson, K. Arai, M. A. Arain, M. C. Araya, S. M. Aston, D. Atkinson, P. Aufmuth, C. Aulbert, B. E. Aylott, S. Babak, P. Baker, S. Ballmer, D. Barker, B. Barr, P. Barriga, L. Barsotti, Tiffany Z. Summerscales Jan 2011

A Gravitational Wave Observatory Operating Beyond The Quantum Shot-Noise Limit, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, C. Adams, R. Adhikari, C. Affeldt, P. Ajith, B. Allen, G. S. Allen, E. Amador Ceron, D. Amariutei, R. S. Amin, S. B. Anderson, W. G. Anderson, K. Arai, M. A. Arain, M. C. Araya, S. M. Aston, D. Atkinson, P. Aufmuth, C. Aulbert, B. E. Aylott, S. Babak, P. Baker, S. Ballmer, D. Barker, B. Barr, P. Barriga, L. Barsotti, Tiffany Z. Summerscales

Faculty Publications

© 2011 Macmillan Publishers Limited. All rights reserved. Around the globe several observatories are seeking the first direct detection of gravitational waves (GWs). These waves are predicted by Einstein's general theory of relativity and are generated, for example, by black-hole binary systems. Present GW detectors are Michelson-type kilometre-scale laser interferometers measuring the distance changes between mirrors suspended in vacuum. The sensitivity of these detectors at frequencies above several hundred hertz is limited by the vacuum (zero-point) fluctuations of the electromagnetic field. A quantum technology - the injection of squeezed light - offers a solution to this problem. Here we demonstrate …


Measurement Of Heavy-Quark Jet Photoproduction At Hera, H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, R. Aggarwal, S. Antonelli, P. Antonioli, A. Antonov, M. Arneodo, V. Aushev, Y. Aushev, O. Bachynska, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, N. Bartosik, D. Bartsch, M. Basile, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, A. Bertolin, S. Bhadra, M. Bindi, C. Blohm, V. Bokhonov, T. Bold, O. Bolilyi, Margarita C. K. Mattingly Jan 2011

Measurement Of Heavy-Quark Jet Photoproduction At Hera, H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, R. Aggarwal, S. Antonelli, P. Antonioli, A. Antonov, M. Arneodo, V. Aushev, Y. Aushev, O. Bachynska, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, N. Bartosik, D. Bartsch, M. Basile, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, A. Bertolin, S. Bhadra, M. Bindi, C. Blohm, V. Bokhonov, T. Bold, O. Bolilyi, Margarita C. K. Mattingly

Faculty Publications

The Author(s) 2011. Photoproduction of beauty and charm quarks in events with at least two jets has been measured with the ZEUS detector at HERA using an integrated luminosity of 133 pb−1. The fractions of jets containing b and c quarks were extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross sections as a function of jet transverse momentum, pjetT, and pseudora pidity, ηjet, were measured. The data are compared with previous measurements and are well described by next-toleading- order QCD predictions.


Review: The Mathematics Of Sex: How Biology And Society Conspire To Limit Talented Women And Girls, Susan Jane Colley Jan 2011

Review: The Mathematics Of Sex: How Biology And Society Conspire To Limit Talented Women And Girls, Susan Jane Colley

Faculty & Staff Scholarship

No abstract provided.


Predatory Ed: The Conflict Between Public Good And For-Profit Higher Education, Osamudia James Jan 2011

Predatory Ed: The Conflict Between Public Good And For-Profit Higher Education, Osamudia James

Faculty Publications

No abstract provided.


Layout-Based Substitution Tree Indexing And Retrieval For Mathematical Expressions, Matthew Schellenberg Jan 2011

Layout-Based Substitution Tree Indexing And Retrieval For Mathematical Expressions, Matthew Schellenberg

Theses

We introduce a new system for layout-based indexing and retrieval of mathematical expressions using substitution trees. Substitution trees can efficiently store and find hierarchically-structured data based on similarity. Previously Kolhase and Sucan applied substitution trees to indexing mathematical expressions in operator tree representation (Content MathML) and query-by-expression retrieval. In this investigation, we use substitution trees to index mathematical expressions in symbol layout tree representation (LaTeX) to group expressions based on the similarity of their symbols, symbol layout, sub-expressions and size. We describe our novel substitution tree indexing and retrieval algorithms and our many significant contributions to the behavior of these …


Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, Peter N. Sedwick, C. M. Marsay, B. M. Sohst, A. M. Aguilar-Islas, M. C. Lohan, M. C. Long, K. R. Arrigo, R. B. Dunbar, M. A. Saito, W. O. Smith, G. R. Ditullio Jan 2011

Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, Peter N. Sedwick, C. M. Marsay, B. M. Sohst, A. M. Aguilar-Islas, M. C. Lohan, M. C. Long, K. R. Arrigo, R. B. Dunbar, M. A. Saito, W. O. Smith, G. R. Ditullio

OES Faculty Publications

The Ross Sea polynya is among the most productive regions in the Southern Ocean and may constitute a significant oceanic CO2sink. Based on results from several field studies, this region has been considered seasonally iron limited, whereby a "winter reserve" of dissolved iron (dFe) is progressively depleted during the growing season to low concentrations (~ 0.1 nM) that limit phytoplankton growth in the austral summer (December-February). Here we report new iron data for the Ross Sea polynya during austral summer 2005-2006 (27 December-22 January) and the following austral spring 2006 (16 November-3 December). The summer 2005-2006 data show …


Analysis Of Hdg Methods For Stokes Flow, Bernardo Cockburn, Jay Gopalakrishnan, Ngoc Cuong Nguyen, Jaume Peraire, Francisco-Javier Sayas Jan 2011

Analysis Of Hdg Methods For Stokes Flow, Bernardo Cockburn, Jay Gopalakrishnan, Ngoc Cuong Nguyen, Jaume Peraire, Francisco-Javier Sayas

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we analyze a hybridizable discontinuous Galerkin method for numerically solving the Stokes equations. The method uses polynomials of degree $ k$ for all the components of the approximate solution of the gradient-velocity-pressure formulation. The novelty of the analysis is the use of a new projection tailored to the very structure of the numerical traces of the method. It renders the analysis of the projection of the errors very concise and allows us to see that the projection of the error in the velocity superconverges. As a consequence, we prove that the approximations of the velocity gradient, the …