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Design And Synthesis Of Mixed Oxides Nanoparticles For Biofuel Applications, Senniang Chen 2010 Iowa State University

Design And Synthesis Of Mixed Oxides Nanoparticles For Biofuel Applications, Senniang Chen

Graduate Theses and Dissertations

The work in this dissertation presents the synthesis of two mixed metal oxides for biofuel applications and NMR characterization of silica materials. In the chapter 2, high catalytic efficiency of calcium silicate is synthesized for transesterfication of soybean oil to biodisels. Chapter 3 describes the synthesis of a new Rh based catalyst on mesoporous manganese oxides. The new catalyst is found to have higher activity and selectivity towards ethanol. Chapter 4 demonstrates the applications of solid state Si NMR in the silica materials.


Competitive Service Market: Modeling, Storage And Management, Shuxing Cheng 2010 Iowa State University

Competitive Service Market: Modeling, Storage And Management, Shuxing Cheng

Graduate Theses and Dissertations

In order to capture the business dynamics underlying SOA-based service systems, we propose and formalize the concept of a competitive service market (CSM). A CSM is composed of a set of composite service providers, each managing a collection of atomic service providers. With the help of service composition protocol, composite service providers are able to invoke atomic services and aggregate them into value-added composite services for servicing various types of customers' requests. Centering around the setting of a competitive service market, our research is separated into three parts:

1. Aiming to support the quantitative-based decision processes of different market players ...


Capture-Based Automated Test Input Generation, Hojun Jaygarl 2010 Iowa State University

Capture-Based Automated Test Input Generation, Hojun Jaygarl

Graduate Theses and Dissertations

Testing object-oriented software is critical because object-oriented languages have been commonly used in developing modern software systems. Many efficient test input generation techniques for object-oriented software have been proposed; however, state-of-the-art algorithms yield very low code coverage (e.g., less than 50%) on large-scale software. Therefore, one important and yet challenging problem is to generate desirable input objects for receivers and arguments that can achieve high code coverage (such as branch coverage) or help reveal bugs. Desirable objects help tests exercise the new parts of the code. However, generating desirable objects has been a significant challenge for automated test input ...


Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne 2010 Iowa State University

Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne

Graduate Theses and Dissertations

The late-glacial (<∼>15 kyr B.P.) advance of the soft-bedded Des Moines Lobe, the marginal portion of an ice stream of the Laurentide Ice Sheet, deposited regularly-spaced, transverse moraines. These so-called washboard moraines have relief of 1-5 m, an average spacing of <∼>105 m, and are distributed over the footprint of the Des Moines Lobe. Determining the processes responsible for the formation of these moraines may help illuminate aspects of Des Moines Lobe dynamics and origins of submarine transverse ridges adjacent to modern ice sheets.

Washboard moraines may have formed as a result of weak basal sediments extruding into transverse ...


Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu 2010 Iowa State University

Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu

Graduate Theses and Dissertations

Stream bank erosion within agricultural landscapes is a major pathway for non-point source sediment and phosphorus loading to receiving waters. The objectives of this study were to: 1) compare the effect of livestock stocking rate on sediment and phosphorus loss from stream bank erosion in the Rathbun Watershed in southern Iowa; 2) assess the relationship between stream stage and stream bank soil erosion rates, and 3) evaluate the impacts of current riparian land-uses and stream morphologic characteristics at the field and catchment scale on stream bank erosion. Stream bank erosion rates over three years were estimated using the erosion pin ...


Characterization Of Proton Exchange Materials For Fuel Cells By Solid State Nuclear Magnetic Resonance, Xueqian Kong 2010 Iowa State University

Characterization Of Proton Exchange Materials For Fuel Cells By Solid State Nuclear Magnetic Resonance, Xueqian Kong

Graduate Theses and Dissertations

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated.

The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by ...


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 ...


Improving Probabilistic Ensemble Forecasts Of Convection Through The Application Of Qpf-Pop Relationships, Christopher John Schaffer 2010 Iowa State University

Improving Probabilistic Ensemble Forecasts Of Convection Through The Application Of Qpf-Pop Relationships, Christopher John Schaffer

Graduate Theses and Dissertations

Quantitative precipitation forecasts provide an accumulated precipitation amount for a given

time period, and accurate forecasts depend on the correct prediction of areal coverage,

timing, and intensity of precipitation. These forecasts are important to a variety of people for

many different purposes, so expressing a likelihood of precipitation is also useful. Most

simply, probabilities of precipitation are determined by considering the percentage of

ensemble members forecasting precipitation greater than a specified threshold amount.

Probabilities of precipitation can also be formed from quantitative precipitation forecasts

through statistical post-processing. Past research has shown that there are many ways to

post-process precipitation data ...


Energy-Efficient Task Assignment Of Wireless Sensor Network With The Application To Agriculture, Songyan Xu 2010 Iowa State University

Energy-Efficient Task Assignment Of Wireless Sensor Network With The Application To Agriculture, Songyan Xu

Graduate Theses and Dissertations

Wireless sensor networks have attracted considerable attention from academia as well as industry. The applications of wireless sensor networks encompass the domains of industrial process monitoring and control, machine health monitoring, environment and habitat monitoring, healthcare applications, home automation, traffic control, etc. In this research we focus on the application of wireless sensor networks to agriculture in which sensors are distributed in a field to monitor the environment and soil of certain interested areas in the field. Given a

set of measurement requests and tasks, it is critical to develop a formal, automatic and energy-efficient approach to assign the set ...


Quantifiable Non-Functional Requirements Modeling And Static Verification For Web Service Compositions, Hongyu Sun 2010 Iowa State University

Quantifiable Non-Functional Requirements Modeling And Static Verification For Web Service Compositions, Hongyu Sun

Graduate Theses and Dissertations

As service oriented architectures have become more widespread in industry, many complex web services are assembled using independently developed modular services from different vendors. Although the functionalities of the composite web services are ensured during the composition process, the non-functional requirements (NFRs) are often ignored in this process. Since quality of services plays a more and more important role in modern service-based systems, there is a growing need for effective approaches to verifying that a composite web service not only offers the required functionality but also satisfies the desired NFRs.

Current approaches to verifying NFRs of composite services (as opposed ...


Evaluating And Understanding The Role Of Convective Processes In General Circulation Model Simulations Of The Madden-Julian Oscillation, Liping Deng 2010 Iowa State University

Evaluating And Understanding The Role Of Convective Processes In General Circulation Model Simulations Of The Madden-Julian Oscillation, Liping Deng

Graduate Theses and Dissertations

Weak temporal variability in tropical climate such as the Madden-Julian Oscillation (MJO) is one of the outstanding deficiencies in numerical weather prediction (NWP) models and coupled general circulation models (GCMs), which have beleaguered the model developer and user communities for years. The representation of convection, cloud and radiation processes has long been recognized as one of the major problems responsible for these deficiencies in climate models. Recently, with the improvement made to the convection scheme, the Iowa State University (ISU) GCM, which is based on the NCAR Community Climate Model version 3 (CCM3), is able to simulate many features of ...


Particle-In-Cell Simulation Of Astrophysical Plasmas: Probing The Origin Of Cosmic Rays, Thomas Alan Stroman 2010 Iowa State University

Particle-In-Cell Simulation Of Astrophysical Plasmas: Probing The Origin Of Cosmic Rays, Thomas Alan Stroman

Graduate Theses and Dissertations

Cosmic rays, the product of natural extraterrestrial particle accelerators far more powerful than the LHC, were first detected a century ago. A "standard model" of cosmic-ray acceleration in supernova remnants has begun to emerge, but a number of questions still require satisfactory answers. The maximum particle energy attainable via the most favored mechanism, diffusive shock acceleration, is limited by the amplitude of magnetic-field turbulence in the unshocked interstellar or circumstellar medium, but cosmic rays are observed at high enough energies that some magnetic-field amplification is required. By what mechanisms might this amplification occur, and can it operate to a great ...


A Genetic Algorithm Approach In Interface And Surface Structure Optimization, Jian Zhang 2010 Iowa State University

A Genetic Algorithm Approach In Interface And Surface Structure Optimization, Jian Zhang

Graduate Theses and Dissertations

The thesis is divided into two parts.In the first part a global optimization method is developed for the interface and surface structures optimization. Two prototype systems are chosen to be studied. One is Si[001] symmetric tilted grain boundaries and the other is Ag/Au induced Si(111) surface. It is found that Genetic Algorithm is very efficient in finding lowest energy structures in both cases. Not only existing structures in the experiments can be reproduced, but also many new structures can be predicted using Genetic Algorithm. Thus it is shown that Genetic Algorithm is a extremely powerful tool ...


The Use Of Plug-In Hybrid Electric Vehicles For Peak Shaving, Benjamin Andrew Maples 2010 University of Colorado at Boulder

The Use Of Plug-In Hybrid Electric Vehicles For Peak Shaving, Benjamin Andrew Maples

Mechanical Engineering Graduate Theses & Dissertations

This thesis entitled The Use of Plug-In Hybrid Electric Vehicles For Peak Shaving by Benjamin Maples, submitted to the department of Mechanical Engineering in partial fulfillment of the degree of Master of Science, performed under the supervision of Professor Frank Kreith, is a feasibility analysis of the capabilities of PHEV's for peak shaving. The analysis focuses on energy availability of the PHEV fleet as well as the potential financial benefit to the vehicle owner by analyzing different charging scenarios and circuitry. The energy availability is heavily dependent on the location and availability of charging stations. The potential consumer profit ...


The Spread Of Computer-Assisted Language Learning, Carol Chapelle 2010 Iowa State University

The Spread Of Computer-Assisted Language Learning, Carol Chapelle

English Publications

This paper argues that the vertical spread of computer-assisted language learning (CALL), i.e., a spread throughout language materials and curricula, makes it difficult to draw a clear distinction between CALL and other language materials. In view of the emphasis that teachers, researchers, and administrators have placed on evaluating CALL, I argue that some valuable lessons about materials evaluation can be drawn from reflection on issues in CALL evaluation. In particular, I discuss the opportunities for professionals to reconsider assumptions held about comparative research, draw upon research perspectives and methods from applied linguistics in materials evaluation, and include critical perspectives ...


United States Land Cover Land Use Change, Albedo And Radiative Forcing: Past And Potential Climate Implications, Christopher A. Barnes 2010 South Dakota State University

United States Land Cover Land Use Change, Albedo And Radiative Forcing: Past And Potential Climate Implications, Christopher A. Barnes

Electronic Theses and Dissertations

Land Cover Land Use (LCLU) change affects Earth surface properties including albedo that impose a radiative forcing on the climate. Recent spatially explicit satellite derived contemporary LCLU, albedo, and projected LCLU data are used to study the impact of LCLU change from 1973 to 2000, and from 2000 to 2050, on albedo and surface radiative forcing for the conterminous United States. Four research hypotheses concerned with past and potential future climate implications of LCLU change are addressed. The research described in this dissertation makes an important contribution to advancing understanding of the role of LCLU change on the climate system ...


Resin-Modified Glass-Ionomer Setting Reaction Competition, David W. Berzins, S. Abey, M. C. Costache, Charles A. Wilkie, H. W. Roberts 2010 Marquette University

Resin-Modified Glass-Ionomer Setting Reaction Competition, David W. Berzins, S. Abey, M. C. Costache, Charles A. Wilkie, H. W. Roberts

Chemistry Faculty Research and Publications

Resin-modified glass ionomers (RMGI) set by at least 2 mechanisms dependent upon reactant diffusion prior to gelation. Each reaction’s kinetics and setting mechanism may rely on and/or compete with the other. In this study, we investigated RMGI setting reaction interactions using differential scanning calorimetry (DSC) by varying light-cure initiation times. A RMGI was analyzed with isothermal and dynamic temperature scan DSC with light-curing occurring immediately, or at 5 or 10 minutes after mixing as well as without light-activation. Results show that as time allowed for the acid-base reaction increased, the light-activation polymerization exotherm decreased. Conversely, analysis of DSC ...


Automation Process For Morphometric Analysis Of Volumetric Ct Data From Pulmonary Vasculature In Rats, Rahul Shingrani, Gary S. Krenz, Robert Molthen 2010 Marquette University

Automation Process For Morphometric Analysis Of Volumetric Ct Data From Pulmonary Vasculature In Rats, Rahul Shingrani, Gary S. Krenz, Robert Molthen

Mathematics, Statistics and Computer Science Faculty Research and Publications

With advances in medical imaging scanners, it has become commonplace to generate large multidimensional datasets. These datasets require tools for a rapid, thorough analysis. To address this need, we have developed an automated algorithm for morphometric analysis incorporating A Visualization Workshop computational and image processing libraries for three-dimensional segmentation, vascular tree generation and structural hierarchical ordering with a two-stage numeric optimization procedure for estimating vessel diameters. We combine this new technique with our mathematical models of pulmonary vascular morphology to quantify structural and functional attributes of lung arterial trees. Our physiological studies require repeated measurements of vascular structure to determine ...


Inadequate Health Numeracy Affects Cancer Screening Practices In Vulnerable Populations, Sherrine Eid MPH, Dorothy Faulkner PhD 2010 Lehigh Valley Health Network

Inadequate Health Numeracy Affects Cancer Screening Practices In Vulnerable Populations, Sherrine Eid Mph, Dorothy Faulkner Phd

Administration & Leadership

No abstract provided.


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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