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Modeling Of Pulse-Echo Inspections Of Multi-Layer Panels Containing Delaminations, Nathaniel Lawrence Richter 2010 Iowa State University

Modeling Of Pulse-Echo Inspections Of Multi-Layer Panels Containing Delaminations, Nathaniel Lawrence Richter

Graduate Theses and Dissertations

To meet the needs of counter insurgency operations the armor of tanks need to be lighter. This is accomplished by using a combination of materials: metals, composites, and ceramics. This multi-material composite armor using any combination of the above materials will need to be inspected for manufacturing error, shipping damage, and combat damage. Nondestructive inspection, particularly ultrasonic inspection, has a long history of successfully inspecting thick composite structures.

To more easily develop inspection plans for many layered composites a computational model would be of use. A model of this type would need to have the ability to account for multiple ...


Alternative Routes For Purification Of Collagen Type I Α1 From A Whole Corn Extract, Christopher Michael Setina 2010 Iowa State University

Alternative Routes For Purification Of Collagen Type I Α1 From A Whole Corn Extract, Christopher Michael Setina

Graduate Theses and Dissertations

Transgenic corn is capable of producing and storing Type I α1 human collagen (r-CIα1) containing a sequence that assists assembly (foldon) and the mature cleaved form (without foldon). Extracts of ground corn grain spiked with Pichia-sourced collagen (rP-CIα1), with and without foldon, were precipitated with NaCl to purify collagen from host cell proteins. The low acid solubility of host cell proteins (HCP's) along with the acid stability of collagen favored extraction at pH 2. NaCl concentrations >0.75 M provided complete precipitation of rP-CIα1 without foldon and >70% purity. A fractional cut to remove HCP's with 0 ...


Establishment Of A Suitable Dynamic Formula For The Construction Control Of Driven Piles And Its Calibration For Load And Resistance Factor Design, Matthew John Roling 2010 Iowa State University

Establishment Of A Suitable Dynamic Formula For The Construction Control Of Driven Piles And Its Calibration For Load And Resistance Factor Design, Matthew John Roling

Graduate Theses and Dissertations

Dynamic pile driving formulas have been available for the field prediction of the static bearing capacity of pile foundations for well over 180 years. On account of the immense number of different formulas that have been amassed during this time frame, a review of published literature was performed to identify the most common dynamic pile driving formulas utilized in the United States and their documented reliability. The results of this review indicated that no one dynamic pile driving formula is consistently better than all the rest; however, the Hiley, Janbu, Pacific Coast Uniform Building Code (PCUBC), and Gates formulas were ...


Partial Nitrification And Oxygen Transfer Analysis Utilizing Hollow Fiber Membrane Aeration, Samuel Wesley Cotter 2010 Iowa State University

Partial Nitrification And Oxygen Transfer Analysis Utilizing Hollow Fiber Membrane Aeration, Samuel Wesley Cotter

Graduate Theses and Dissertations

Excess nutrients in lakes, rivers, and streams harm aquatic ecosystems.y Advanced treatment at wastewater treatment plants can reduce this pollutant load.y An innovative nutrient removal system, ANAMMOX, anaerobically converts ammonium and nitrite to N2 gas.y Because this system requires a 1:1.31 NH4+ : NO2 ratio, a partial nitrification system is coupled with the ANAMMOX system to provide the necessary substrates.y A hollow fiber membrane reactor was employed to create this partial nitrification system.y Gas mass transfer was first evaluated to determine the KLa oxygen transfer coefficient. Reactor parameters, such ...


Behavior Characterization And Development Of Lrfd Resistance Factors For Axially-Loaded Steel Piles In Bridge Foundations, Sherif Sayed Abdelsalam 2010 Iowa State University

Behavior Characterization And Development Of Lrfd Resistance Factors For Axially-Loaded Steel Piles In Bridge Foundations, Sherif Sayed Abdelsalam

Graduate Theses and Dissertations

The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new bridges initiated in the United States after October 1, 2007. Consequently, significant efforts have been directed by Departments of Transportation (DOTs) in different states towards the development and implementation of the LRFD approach for the design of bridge's deep foundations. The research presented in this thesis is aimed at establishing the LRFD resistance factors for the design of driven pile foundations by accounting for local soil and pile construction practices. Accordingly, regional LRFD resistance factors have been developed for different static ...


Using An Autothrottle To Compare Techniques For Saving Fuel On A Regional Jet Aircraft, Rebecca Marie Johnson 2010 Iowa State University

Using An Autothrottle To Compare Techniques For Saving Fuel On A Regional Jet Aircraft, Rebecca Marie Johnson

Graduate Theses and Dissertations

With rising fuel costs there is an initiative to conserve fuel during fight. Several methods have been proposed to calculate an optimum speed to y during cruise flight to maximize the range of a particular aircraft. This paper compares 11 of these methods using the same aircraft model and discusses how to implement these techniques in an autothrottle. Alternative implementations also include adding the algorithm to the Flight Management System to use during flight planning, or to including it in the databases to use during dispatch calculations. The results show that the speeds calculated by these methods are more fuel ...


Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner 2010 Iowa State University

Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner

Graduate Theses and Dissertations

Glycoside hydrolases (GH) are enzymes that hydrolyze glycosidic bonds between carbohydrates. Family 44 contains endo- and xylo- glucanases capable of hydrolyzing cellulose and hemicelluose. Two members produced by Clostridium acetobutylicum and Ruminococcus flavefaciens FD-1 are the subjects of characterization work in this dissertation.

The EG from Clostridium acetobutylicum was characterized both structurally and kinetically. Crystallization and x-ray diffraction to 2.2-y resolution revealed a TIM barrel-like structure with additional ψ-loop and β-sandwich folds. The EG hydrolyzes cellotetraose and larger cellooligosaccharides, as well as carboxymethylcellulose and xylan at approximately the same rates. It converts lichenan to oligosaccharides of intermediate size and ...


Spatio-Temporal Patterns Of Field-Scale Soil Moisture And Their Implications For In Situ Soil Moisture Network Design, Lingyuan Yang 2010 Iowa State University

Spatio-Temporal Patterns Of Field-Scale Soil Moisture And Their Implications For In Situ Soil Moisture Network Design, Lingyuan Yang

Graduate Theses and Dissertations

This dissertation describes efforts to overcome the challenges in designing in situ soil moisture observation network. The surface soil moisture data collected at two spatial scales in a working field in Iowa throughout the growing seasons in 2004 to 2008 were used to describe the spatio-temporal characteristics of soil moisture at field scale. The rank stability analysis was used to identify the locations on the ground to represent the mean soil moisture at the field scale across five different growing seasons. Optimal sampling locations (OSLs), giving accurate estimates of field mean soil moisture for each season, were selected using the ...


Integral Equation Analysis Of Electromagnetic Wave Propagation In Periodic Structure And Error Analysis Of Various Basis Functions In Projection Of Plane Waves, Fu-gang Hu 2010 Iowa State University

Integral Equation Analysis Of Electromagnetic Wave Propagation In Periodic Structure And Error Analysis Of Various Basis Functions In Projection Of Plane Waves, Fu-Gang Hu

Graduate Theses and Dissertations

In the first part of this dissertation, the integral equation approaches are developed to analyze the wave propagation in periodic structures. Firstly, an integral equation approach is developed to analyze the two-dimensional (2-D) scattering from multilayered periodic array. The proposed approach is capable of handling scattering from the array filled with different media in different layers.

Combining the equivalence principle algorithm and connection scheme (EPACS), it can be avoided to find and evaluate the multilayered periodic Green's functions. For 2^N identical layers, the elimination of the unknowns between top and bottom surfaces can be accelerated using the logarithm ...


Hierarchically Ordered Montmorillonite Block Copolymer Brushes, Ross Eric Behling 2010 Iowa State University

Hierarchically Ordered Montmorillonite Block Copolymer Brushes, Ross Eric Behling

Graduate Theses and Dissertations

We report the phase behavior of a new class of polymer

nanocomposites, montmorillonite (MMT) block copolymer brushes

(MBBs). MBBs are comprised of discrete MMT particles encapsulated with block copolymer brushes synthesized via surface initiated atom transfer radical polymerization. Polystyrene-b-poly(n-butyl acrylate) MBBs of varying composition and total Mn = 80--250 kDa were compared with bulk block copolymers via electron

microscopy and a host of mechanical tests. MBBs were found to self

assemble into single grain morphologies across incredibly large

areas (> 3 um). Perhaps most promising is that MBBs maintain

similar melt state properties to bulk block copolymers and are thus

amenable ...


Web-Based Collaboration In Horizontal Construction, Aaron Charles Zutz 2010 Iowa State University

Web-Based Collaboration In Horizontal Construction, Aaron Charles Zutz

Graduate Theses and Dissertations

Web-based collaboration tools offer many benefits in the management of construction projects. These systems have become increasing popular in the vertical construction sector; however, they have not been widely implemented in the horizontal construction sector. Research was completed to determine how prevalent the use of web-based collaboration software is with state departments of transportations (DOT) and what needs exist within state DOTs for web-based collaboration.

To learn how web-based collaboration could be implemented within state DOTs a pilot project was conducted with the Iowa DOT. This project focused on identifying the Iowa DOT's project management needs on bridge projects ...


Improving Particle Swarm Optimization Path Planning Through Inclusion Of Flight Mechanics, Joseph Scott Holub 2010 Iowa State University

Improving Particle Swarm Optimization Path Planning Through Inclusion Of Flight Mechanics, Joseph Scott Holub

Graduate Theses and Dissertations

Military engagements are continuing the movement toward automated and unmanned vehicles for a variety of simple and complex tasks. This allows humans to stay away from dangerous situations and use their skills for more difficult tasks. One important piece of this strategy is the use of automated path planners for unmanned aerial vehicles (UAVs). Current UAV operation requires multiple individuals to control a single plane, tying up important human resources. Often paths are planned by creating waypoints for a vehicle to fly through, with the intention of doing reconnaissance while avoiding as much danger to the plane as possible. Path ...


A Comparison Study Of Digital Sinusoidal Fringe Generation Technique: Defocusing Binary Patterns Vs Focusing Sinusoidal Patterns, Shuangyan Lei 2010 Iowa State University

A Comparison Study Of Digital Sinusoidal Fringe Generation Technique: Defocusing Binary Patterns Vs Focusing Sinusoidal Patterns, Shuangyan Lei

Graduate Theses and Dissertations

With the recent advancements in digital technology, three-dimensional (3-D) shape measurement has played an increasingly important role in fields including manufacturing, homeland security, medical sciences, and entertainment. Over the past decades, numerous 3-D shape measurement techniques have been developed. Among these existing techniques, fringe analysis based on phase-shifting sinusoidal structured patterns stands out because of its numerous advantages. However, there are still some major challenges of the existing digital fringe projection system for accurate 3-D shape measurement and for future speed improvement. They are: (1) projector nonlinearity problem, (2) synchronization problem, and (3) exposure time limitation problem. There are currently ...


Integrating Modern Business Methodologies And Behavior Factors To Better Apply Information Technology Security Practices Within The Organization, Brian Matthew Edwards 2010 Iowa State University

Integrating Modern Business Methodologies And Behavior Factors To Better Apply Information Technology Security Practices Within The Organization, Brian Matthew Edwards

Graduate Theses and Dissertations

Often in today's business environments, data collected through great care and effort never transforms into actionable information and intelligence because organizations lack the tools or skills to apply modern practices. Too many well developed tools exist but are overlooked. Too many projects fail to account for their organization's social and cultural attributes. The result is information being discarded because it cannot be effectively leveraged.

This work examines a collection of business tools and technologies, goals, and behaviors in the context of how they affect information security policy and programs within the business.


Design And Evaluation Of Variable Rate Stover Collection Control System For A Single Pass Dual Stream Biomass Harvester System, Robert Paul Mcnaull 2010 Iowa State University

Design And Evaluation Of Variable Rate Stover Collection Control System For A Single Pass Dual Stream Biomass Harvester System, Robert Paul Mcnaull

Graduate Theses and Dissertations

The increased need for renewable fuel sources has driven research to focus on agricultural by-products in the form of corn stover. Corn stover is the single largest available biomass feedstock in the U.S. and is also a vital part of agriculture as it provides soil protection and maintains the carbon cycle. Removing this material requires it be done using sustainable practices, with this research focusing specifically on protecting soil loss. Achieving this requires variable rate removal of corn stover to provide site specific management to account for spatial variability of a field by field basis. Utilizing two modes of ...


Transfer Operator-Based Approach For Domain Of Attraction Computation And Experimental Data Analysis, Kai Wang 2010 Iowa State University

Transfer Operator-Based Approach For Domain Of Attraction Computation And Experimental Data Analysis, Kai Wang

Graduate Theses and Dissertations

We present novel transfer operator-based methods for domain of attraction computation and experimental data analysis of nonlinear systems. The problem of domain of attraction (DA) computation is of great practical interest with applications in various engineering and physical systems such as power system, chemical processes, aircraft control, and biological systems. We propose linear transfer operator-based set-oriented numerical method for DA computation of nonlinear systems. The proposed method overcomes some of the shortcoming of the existing methods of DA computation; in particular the proposed method can be used for DA computation of non-polynomial vector fields and for systems with non-equilibrium dynamics ...


Novel Sensorless Generator Control And Grid Fault Ride-Through Strategies For Variable-Speed Wind Turbines And Implementation On A New Real-Time Simulation Platform, Sheng Yang 2010 Iowa State University

Novel Sensorless Generator Control And Grid Fault Ride-Through Strategies For Variable-Speed Wind Turbines And Implementation On A New Real-Time Simulation Platform, Sheng Yang

Graduate Theses and Dissertations

The usage of MW-size variable-speed wind turbines as sources of energy has increased significantly during the last decade. Advantages over fixed-speed wind turbines include more efficient wind power extraction, reduced grid power fluctuation, and improved grid reactive power support. Two types of typical generation systems for large-size variable-speed wind turbines exist. One is the doubly-fed induction generator (DFIG) with a partial-scale power electronic converter. The other is the permanent-magnet synchronous generator (PMSG) with a full-scale power electronic converter. This research is to develop the model of these two wind turbine systems for real-time simulation, including the complete aerodynamic and mechanical ...


Machining Induced Defects In Relaxor Ferroelectric Pmn-Pt Crystals, Cheng Deng 2010 Iowa State University

Machining Induced Defects In Relaxor Ferroelectric Pmn-Pt Crystals, Cheng Deng

Graduate Theses and Dissertations

The superior piezoelectric and dielectric properties of the relaxor based piezoelectric single crystals (PMN-PT) render them as prime candidates for Navy sonar detectors as well as broad band medical ultrasonic imaging devices. Production of phased array probes utilizing these types of high performance ceramics requires dicing these crystals to arrays with pitches of less than the desired wavelength, ranging from tens to hundreds of micrometers. However, the relaxor based single crystals are very brittle with fracture toughness of about a third to a half that of typical PZT ceramics ( ). Excessive chipping and cracking, either during the cutting or poling process ...


Contextual Self-Organizing Maps For Visual Design Space Exploration, Brett Nekolny 2010 Iowa State University

Contextual Self-Organizing Maps For Visual Design Space Exploration, Brett Nekolny

Graduate Theses and Dissertations

Visualization of an optimization problem (i.e the "design space") becomes complex when the number of independent variables of the problem increases beyond two. Unfortunately, realistic optimization problems and their design spaces are often greater than two dimensions and therefore difficult to visualize. In order to create and display in greater than three dimensions it is necessary to use color, size, or symbols to show added dimensions. With the complexity in a visualization that uses these extra dimensional features, an observer is often overloaded with data and it can be difficult to grasp a firm understanding of the relationships therein ...


Methods For Integrated Biochemical Pathway Analysis, John Louis Van Hemert 2010 Iowa State University

Methods For Integrated Biochemical Pathway Analysis, John Louis Van Hemert

Graduate Theses and Dissertations

The common goal for biological research is to develop models for the biological processes we seek to understand. Such models, in the form of biochemical pathway networks which describe the physical interactions between a living cell's genes, transcripts, proteins, and metabolites ("Omics"), accumulate in different repositories for several model organisms as well as non-model organisms. This thesis presents a set of integrated statistical bioinformatics tools that address key problems in integrating large-scale Omics datasets with pathway network models. A hardware accelerated non-parametric Omics mining method (Monte Carlo on the GPU) allows faster screening of custom test statistics and functions ...


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