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A Framework For Active Learning: Revisited, Yue Chen 2010 San Jose State University

A Framework For Active Learning: Revisited, Yue Chen

Master's Projects

Over the past decade, algorithm visualization tools have been researched and developed to be used by Computer Science instructors to ease students’ learning curve for new concepts. However, limitations such as rigid animation frameworks, lack of user interaction with the visualization created, and learning a new language and environment, have severely reduced instructors’ desire to use such a tool. The purpose of this project is to create a tool that overcomes these limitations. Instructors do not have to get familiar with a new framework and learn another language. The API used to create algorithm animation for this project is through ...


Automatic Grading Of Programming Assignments, Ashlesha Patil 2010 San Jose State University

Automatic Grading Of Programming Assignments, Ashlesha Patil

Master's Projects

Solving practical problems is one of the important aspects of learning programming languages. But the assessment of programming problems is not straightforward. It involves time consuming and tedious steps required to compile and test the solution. In this project, I have developed a online tool, Javabrat that allows the students and language learners to practice Java and Scala problems. Javabrat automatically assesses the user's program and provides the instant feedback to the user. The users can also contribute their own programming problems to the existing problem set. I have also developed a plugin for a learning management system, Moodle ...


A Mathematical Model For Il6-Induced Differentiation Of Neural Progenitor Cells On A Micropatterned Polymer Substrate, Cory Howk 2010 Iowa State University

A Mathematical Model For Il6-Induced Differentiation Of Neural Progenitor Cells On A Micropatterned Polymer Substrate, Cory Howk

Graduate Theses and Dissertations

Neural progenitor cells (NPC) hold potential for repairing the injured and diseased central nervous system, and because of this we would like to better understand the mechanisms of NPC migration and differentiation. Previous in vitro research has shown that adult rat hippocampal progenitor cells (AHPC) differentiate into neurons in response to hippocampal astrocyte-secreted factors, including the cytokine IL6. This work is a mathematical study of a simple mechanism for IL6-induced AHPC differentiation. We show that all experimental results under consideration can be replicated by this model. A global sensitivity analysis is performed, demonstrating that the inhibitor of this pathway does ...


A Small Area Procedure For Estimating Population Counts, Emily J. Berg 2010 Iowa State University

A Small Area Procedure For Estimating Population Counts, Emily J. Berg

Graduate Theses and Dissertations

Many large scale surveys are designed to achieve acceptable reliability for large domains. Direct estimators for more detailed levels of aggregation are often judged to be unreliable due to small sample sizes. Estimation for small domains, often defined by geographic and demographic characteristics, is known as small area estimation. A common approach to small area estimation is to derive predictors under a specified mixed model for the direct estimators. A procedure of this type is developed for small areas defined by the cells of a two-way table.

Construction of small domain estimators using the Canadian Labour Force Survey (LFS) motivates ...


Closed Time-Like Curves And Inertial Frame Dragging: How To Time Travel Via Spacetime Rotation, Conrad Wilson Moore 2010 Bucknell University

Closed Time-Like Curves And Inertial Frame Dragging: How To Time Travel Via Spacetime Rotation, Conrad Wilson Moore

Honors Theses

As the number of solutions to the Einstein equations with realistic matter sources that admit closed time-like curves (CTC's) has grown drastically, it has provoked some authors [10] to call for a physical interpretation of these seemingly exotic curves that could possibly allow for causality violations. A first step in drafting a physical interpretation would be to understand how CTC's are created because the recent work of [16] has suggested that, to follow a CTC, observers must counter-rotate with the rotating matter, contrary to the currently accepted explanation that it is due to inertial frame dragging that CTC ...


Volume Of An Industrial Autoclave, Nicholas Madaffari 2010 University of South Florida

Volume Of An Industrial Autoclave, Nicholas Madaffari

Undergraduate Journal of Mathematical Modeling: One + Two

We were able to determine the volume of an industrial autoclave sterilization tank using a technique learned in calculus. By measuring the dimensions of the tank and roughly estimating the equation of curvature at the ends of the tank, we were able to revolve half of the end of the tank around the x axis to get its fluid volume. Adding the two volumes of the ends and the volume of the cylindrical portion on the tank yielded the total volume.


Escape Velocity, Nikola Vlacic 2010 University of South Florida

Escape Velocity, Nikola Vlacic

Undergraduate Journal of Mathematical Modeling: One + Two

In this project, we investigated if it is feasible for a single staged rocket with constant thrust to attain escape velocity. We derived an equation for the velocity and position of a single staged rocket that launches vertically. From this equation, we determined if an ideal model of a rocket is able to reach escape velocity.


Stormwater Management System Drawdown, Ahmad Chehab 2010 University of South Florida

Stormwater Management System Drawdown, Ahmad Chehab

Undergraduate Journal of Mathematical Modeling: One + Two

This project concerns the computations required to determine the drawdown for the retention/detention of ponds. Drawdown refers to the volume of water in a pond that decreases as the water flows out. The falling head equation has many applications and can be used to calculate the drawdown of a pond through various shaped openings. In particular, we analyze four outflow structures: a rectangular-notch weir, a v-notch weir, a round orifice, and an underdrain. For each instance, we modify the falling head equation to reflect the shape of the respective orifice.


Radiographic Imagery Of A Variable Density 3d Object, Justin Stottlemyer 2010 University of South Florida

Radiographic Imagery Of A Variable Density 3d Object, Justin Stottlemyer

Undergraduate Journal of Mathematical Modeling: One + Two

The purpose of this project is to develop a mathematical model to study 4D (three spatial dimensions plus density) shapes using 3D projections. In the model, the projection is represented as a function that can be applied to data produced by a radiation detector. The projection is visualized as a three-dimensional graph where x and y coordinates represent position and the z coordinate corresponds to the object's density and thickness. Contour plots of such 3D graphs can be used to construct traditional 2D radiographic images.


Predator-Prey Modeling, Shaza Hussein 2010 University of South Florida

Predator-Prey Modeling, Shaza Hussein

Undergraduate Journal of Mathematical Modeling: One + Two

Predator-prey models are useful and often used in the environmental science field because they allow researchers to both observe the dynamics of animal populations and make predictions as to how they will develop over time. The objective of this project was to create five projections of animal populations based on a simple predator-prey model and explore the trends visible. Each case began with a set of initial conditions that produced different outcomes for the function of the population of rabbits and foxes over an 80 year time span. Using Euler's method, an Excel spreadsheet was developed to produce the ...


Studies Of Aspect Angle Dependence Of Plasma Turbulence At Haarp, Nargis Adham 2010 Eastern Michigan University

Studies Of Aspect Angle Dependence Of Plasma Turbulence At Haarp, Nargis Adham

Master's Theses and Doctoral Dissertations

We report the results from a recent series of campaigns employing the HAARP HF transmitter to generate and study strong Langmuir turbulence (SLT) in the interaction region of overdense ionospheric plasma. Diagnostics included the Modular UHF Ionospheric Radar (MUIR) sited at HAARP, the Super DARN-Kodiak HF radar, and HF receivers to record stimulated electromagnetic emissions (SEE). Short pulse, low duty cycle experiments demonstrate control and suppression of artificial field-aligned irregularities (AFAI). This allows the isolation of ponderomotive plasma turbulence effects. Plasma line spectra exhibit a marked dependence on the aspect angle of the HF pump beam and the pointing of ...


Recommender System For Audio Recordings, Jong Seo Lee 2010 California Polytechnic State University - San Luis Obispo

Recommender System For Audio Recordings, Jong Seo Lee

Master's Theses and Project Reports

Nowadays the largest E-commerce or E-service websites offer millions of products for sale. A Recommender system is defined as software used by such websites for recommending commercial or noncommercial product items to users according to the users’ tastes. In this project, we develop a recommender system for a private multimedia web service company. In particular, we devise three recommendation engines using different data filtering methods – named weighted-average, K-nearest neighbors, and item-based – which are based on collaborative filtering techniques, which work by recording user preferences on items and by anticipating the future likes and dislikes of users by comparing the records ...


Effects Of Silver Nanoparticles On Photochemical Processes Focusing On Luminol Chemiluminescence, Scott Milam 2010 Eastern Michigan University

Effects Of Silver Nanoparticles On Photochemical Processes Focusing On Luminol Chemiluminescence, Scott Milam

Master's Theses and Doctoral Dissertations

Silver nanoparticles of varying sizes were synthesized. Their effects on enhancing or quenching the photochemical processes of tryptophan fluorescence, a ruthenium complex decay constant and chemiluminescence of luminol and ferricyanide, were studied. The tryptophan fluorescence was slightly enhanced by smaller nanoparticles and showed slight quenching in the presence of larger nanoparticles. The tris (2,2’-bipyridyl ruthenium (II) chloride) complex was excited using a 532 nm laser, and the decay constant was measured. Neither gold nor silver nanoparticles showed an impact on this process. The luminol chemiluminescence was studied with an emphasis on holding the concentration of nanoparticles, surface area ...


Green Composites And Coatings From Agricultural Feedstocks, Daniel Patrick Pfister 2010 Iowa State University

Green Composites And Coatings From Agricultural Feedstocks, Daniel Patrick Pfister

Graduate Theses and Dissertations

Green composites have been produced from natural oils and agricultural co-products or residues. A variety of natural oil-based resins, both free radically- and cationically-cured, and agricultural filler/fiber reinforcements have been utilized in their production. The natural oils and agricultural filler/fibers of interest include tung, corn, soybean, fish, and linseed oils and spent germ, corn stover, wheat straw, and switchgrass. The structure, water absorption, and thermal and mechanical properties of the composites has been studied using Soxhlet extraction, thermogravimetric and dynamic mechanical analysis and tensile testing. These novel composites contain anywhere from 60 to 95% renewable materials and have ...


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 ...


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 ...


Modular Synthesis Of Weinreb Amides Of 2-Fluoro-2,4-Dienoic Acids, Mohammad Chowdhury 2010 CUNY City College

Modular Synthesis Of Weinreb Amides Of 2-Fluoro-2,4-Dienoic Acids, Mohammad Chowdhury

Dissertations and Theses

No abstract provided.


Metabolic Engineering For Production Of Biorenewable Fuels And Chemicals: Contributions Of Synthetic Biology, Laura R. Jarboe, Xueli Zhang, Xuan Wang, Jonathan C. Moore, K. T. Shanmugam, Lonnie O. Ingram 2010 Iowa State University

Metabolic Engineering For Production Of Biorenewable Fuels And Chemicals: Contributions Of Synthetic Biology, Laura R. Jarboe, Xueli Zhang, Xuan Wang, Jonathan C. Moore, K. T. Shanmugam, Lonnie O. Ingram

Chemical and Biological Engineering Publications

Production of fuels and chemicals through microbial fermentation of plant material is a desirable alternative to petrochemicalbased production. Fermentative production of biorenewable fuels and chemicals requires the engineering of biocatalysts that can quickly and efficiently convert sugars to target products at a cost that is competitive with existing petrochemical-based processes. It is also important that biocatalysts be robust to extreme fermentation conditions, biomass-derived inhibitors, and their target products. Traditional metabolic engineering has made great advances in this area, but synthetic biology has contributed and will continue to contribute to this field, particularly with next-generation biofuels. This work reviews the use ...


Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson 2010 Iowa State University

Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson

Chemical and Biological Engineering Publications

Protein-lean fractions of corn (maize) containing recombinant (r) pharmaceutical proteins were evaluated as a potential feedstock to produce fuel ethanol. The levels of residual r-proteins in the coproduct, distillers dry grains with solubles (DDGS), were determined. Transgenic corn lines containing recombinant green fluorescence protein (r-GFP) and a recombinant subunit vaccine of Escherichia coli enterotoxin (r-LTB), primarily expressed in endosperm, and another two corn lines containing recombinant human collagen (r-CIα1) andr-GFP, primarily expressed in germ, were used as model systems. The kernels were either ground and used for fermentation or dry fractionated to recover germ-rich ...


Not Every Co-Existential Map Is Confluent, Paul Bankston 2010 Marquette University

Not Every Co-Existential Map Is Confluent, Paul Bankston

Mathematics, Statistics and Computer Science Faculty Research and Publications

A continuous surjection between compacta is co-existential if it is the second of two maps whose composition is a standard ultracopower projection. Co-existential maps are always weakly confluent, and are even monotone when the range space is locally connected; so it is a natural question to ask whether they are always confluent. Here we give a negative answer. This is an interesting question, mainly because of the fact that most theorems about confluent maps have parallel versions for co-existential maps---notably, both kinds of maps preserve hereditary indecomposability. Where the known parallels break down is in the question of chainability. It ...


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