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Articles 116941 - 116970 of 193998

Full-Text Articles in Engineering

Validation Of A Resonant Frequency Model For Polypyrrole Trilayer Actuators, S. W. John, G. Alici, C. Cook Mar 2012

Validation Of A Resonant Frequency Model For Polypyrrole Trilayer Actuators, S. W. John, G. Alici, C. Cook

Gursel Alici

Conducting polymers are new materials that can be used as low-voltage actuators and active flexure joints, scaling down to the microscale; however, many devices based on these actuators are limited because they can only operate when submerged in an electrolyte. Conducting polymer trilayer actuators are laminated structures with a wide range of potential applications as they are capable of operating both in air and liquid environments, but their dynamic behavior is not yet fully understood.With the view to developing a comprehensive dynamic model of trilayer actuators, this paper presents the experimentally obtained frequency response of the actuator displacement, as measured …

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A Robust Motion Design Technique For Flexible-Jointed Manipulation Systems, G. Alici, S. Kapucu, S. Baysec Mar 2012

A Robust Motion Design Technique For Flexible-Jointed Manipulation Systems, G. Alici, S. Kapucu, S. Baysec

Gursel Alici

This paper presents a robust input shaping technique that significantly reduces (almost eliminates) the residual vibration of manipulation systems typified by a flexiblejointed robot manipulator. The technique consists of two stages. In the first stage, a ramp function is superimposed onto the main trajectory to be preshaped. In the second stage, the outcome of the first stage is convolved with a sequence of two impulses. The robustness of the technique to the uncertainties in the system natural frequency and damping ratio are quantified through simulation and experimental evaluation. Simulation and experimental results demonstrate that the technique is not only effective …

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A New Methodology For Deformable Object Simulation, Yongmin Zhong, Bijan Shirinzadeh, Gursel Alici, Julian Smith Mar 2012

A New Methodology For Deformable Object Simulation, Yongmin Zhong, Bijan Shirinzadeh, Gursel Alici, Julian Smith

Gursel Alici

This paper presents a new methodology for the deformation of soft objects by drawing an analogy between heat conduction and elastic deformation. The potential energy stored in an elastic body as a result of a deformation caused by an external force is propagated among mass points by the principle of heat conduction. An improved heat conduction model is developed for propagating the energy generated by the external force in a natural manner. A method is presented to derive the internal forces from the potential energy distribution. This methodology not only deals with large-range deformation, but also accommodates both isotropic and …

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Optimum Dynamic Balancing Of Planar Parallel Manipulators, G. Alici, B. Shirinzadeh Mar 2012

Optimum Dynamic Balancing Of Planar Parallel Manipulators, G. Alici, B. Shirinzadeh

Gursel Alici

This paper presents a methodology for optimum dynamic balancing of planar parallel manipulators typified with a variable speed 2 DOF parallel manipulator articulated with revolute joints. The dynamic balancing is formulated as an optimisation problem such that a sum-squared values of bearing forces, driving torques, shaking moment, and the deviation of the angular momentum from its mean value are minimized throughout an operation range of the manipulator, provided that a set of balancing constraints consisting of the shaking force balancing conditions, the sizes of some inertial and geometric parameters are satisfied. Sets of optimisation results corresponding to various combinations of …

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Characterisation And Bending Modeling Of Conducting Polymer Actuators For Use In Micro/Nano Manipulation, G. Alici, B. Mui, C. Cook Mar 2012

Characterisation And Bending Modeling Of Conducting Polymer Actuators For Use In Micro/Nano Manipulation, G. Alici, B. Mui, C. Cook

Gursel Alici

As research efforts towards making functional micro/nano robotics system gather more momentum, there is an increasing need for new actuators that can not only be suitable to miniaturization, but also be free from sliding and rolling elements so that they can generate a motion resolution and accuracy in a submicron range. Conducting polymer actuators have many features to satisfy such a strict requirements. Before introducing them to the micro/nano robotics world, it is necessary to investigate into their actuation mechanism and the smallest displacement they can generate. In this paper, we report on the characterization and modelling of a strip-type …

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Size Optimisation Of Polypyrrole (Ppy) Actuators For Micro/Nano Manipulation Systems, Gursel Alici, Philippe Metz, Geoffrey M. Spinks Mar 2012

Size Optimisation Of Polypyrrole (Ppy) Actuators For Micro/Nano Manipulation Systems, Gursel Alici, Philippe Metz, Geoffrey M. Spinks

Gursel Alici

PPy actuators have many features suitable for many cutting edge applications ranging from biomedical to micro/nano manipulation systems. In this paper, we first establish a mathematical model describing the voltage input, and bending displacement and force outputs of the PPy actuators, and then use the model to optimise/improve their shape. With reference to their operation principle, we draw an analogy between the thermal strain and the real strain in the PPy actuators due to the volume change to establish the mathematical model, which is a coupled structural/thermal model. The finite element method (FEM) is employed to solve the model. The …

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Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace Mar 2012

Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace

Gursel Alici

The characterization of the dynamic response (including transfer function identification) of trilayer polypyrrole (PPy) type conducting polymer sensors is presented. The sensor was built like a cantilever beam with the free end stimulated through a mechanical lever system, which provided displacement inputs. The voltage generated and current passing between the two outer PPy layers as a result of the input was measured to model the output/input behavior of the sensors based on their experimental current/displacement and voltage/displacement frequency responses. We specifically targeted the low-frequency behavior of the sensor as it is a relatively slowsystem. Experimental transfer function models were generated …

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Scale Model Shake Table Testing Of Seismic Earth Pressures In Soft Clay, Robb Moss, R.E. Noche Mar 2012

Scale Model Shake Table Testing Of Seismic Earth Pressures In Soft Clay, Robb Moss, R.E. Noche

Civil and Environmental Engineering

There is much uncertainty in seismic earth pressures for basement wall design and retaining wall design in clay soil. The research presented herein uses a scale model testing platform on a 1g shake table to measure the distribution and magnitude of seismic earth pressures for the prototype soil conditions of San Francisco Young Bay Mud (YBM). Similitude scaling of the dynamic soil properties, the wall dimensions, and the input time histories (among other variables) affords accurate modeling of the prototype scale wall. For basement conditions, inertial soil structure interaction (SSI) effects are included in the experiments. Care is taken to …

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Interaction Between Electromagnetic Waves And Transport In Saturated Media, Mahsa Azad, Harlan Sangrey, Arvin Farid, Jim Browning, Elisa Barney Smith Mar 2012

Interaction Between Electromagnetic Waves And Transport In Saturated Media, Mahsa Azad, Harlan Sangrey, Arvin Farid, Jim Browning, Elisa Barney Smith

Civil Engineering Faculty Publications and Presentations

Air sparging is one of the most popular remediation technologies. However, it is limited to a small radius of influence (ROI) surrounding the air injection well. Hence, there have been several efforts to improve its effectiveness. To study the possibility of improving the effectivity of air sparging electromagnetic (EM) waves, an easily visible analogous problem (dye transport in water) is studied in this paper. In order to quantify the effects of EM stimulation on flow of an inert, nonreactive dye in water, EM-stimulated and unstipulated dye transport experiments tests were performed and compared. To quantify this interaction, both dye transport …

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Using Avhrr-Based Vegetation Health Indices For Estimation Of Potato Yield In Bangladesh, Rahman A., Kaiser Khan, Nir Y. Krakauer, Leonid Roytman, Kogan F. Mar 2012

Using Avhrr-Based Vegetation Health Indices For Estimation Of Potato Yield In Bangladesh, Rahman A., Kaiser Khan, Nir Y. Krakauer, Leonid Roytman, Kogan F.

Publications and Research

We developed a model correlating Advanced Very High Resolution Radiometer (AVHRR)-based Temperature Condition Index (TCI) and Vegetation Condition Index (VCI) with potato yield in Bangladesh. Weekly TCI and VCI Indices for 1993–2005 along with official potato yield statistics were used for model development. We found a strong correlation between inter annual variation in potato yield and TCI and VCI during the critical period of potato growth (vegetative phase and tuber initiation), mid-December to mid-January. Principal component regression (PCR) was used to construct a model to predict potato yield as function of TCI and VCI. The model explained about 75% of …

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Student-Focused Learning Programs: Designing And Delivering, Susan Ariew, Matt Torrence Mar 2012

Student-Focused Learning Programs: Designing And Delivering, Susan Ariew, Matt Torrence

Matt Torrence

Librarians typically have limited time during one-shot library instruction sessions, so supplementing instruction with asynchronous reusable learning objects (videos, tutorials, Prezi presentations, LibGuides, etc) allows them to maximize their time with students in all environments. Embedded librarian, Susan Ariew, will illustrate the reusable learning objects she uses in course management systems to prepare students for classes to get them beyond the basics and prime them for meaningful librarian/student instructional sessions. From in-studio production to laptop simplicity, we've tried it all in terms of video instruction. Engineering & Business Librarian Matt Torrence will talk about the production side of things, illustrating …

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Whole-Genome Resequencing Of Two Elite Sires For The Detection Of Haplotypes Under Selection In Dairy Cattle Supporting Information, Denis M. Larkin, Hans D. Daetwyler, Alvaro G. Hernandez, Chris L. Wright, Lorie A. Hetrick, Lisa Boucek, Sharon Bachman, Jyothi Thimmapuram Mar 2012

Whole-Genome Resequencing Of Two Elite Sires For The Detection Of Haplotypes Under Selection In Dairy Cattle Supporting Information, Denis M. Larkin, Hans D. Daetwyler, Alvaro G. Hernandez, Chris L. Wright, Lorie A. Hetrick, Lisa Boucek, Sharon Bachman, Jyothi Thimmapuram

Cyber Center Publications

Using a combination of whole-genome resequencing and high-density genotyping arrays, genome-wide haplotypes were reconstructed for two of the most important bulls in the history of the dairy cattle industry, Pawnee Farm Arlinda Chief (“Chief”) and his son Walkway Chief Mark (“Mark”), each accounting for ∼7% of all current genomes. We aligned 20.5 Gbp (∼7.3× coverage) and 37.9 Gbp (∼13.5× coverage) of the Chief and Mark genomic sequences, respectively. More than 1.3 million high-quality SNPs were detected in Chief and Mark sequences. The genome-wide haplotypes inherited by Mark from Chief were reconstructed using ∼1 million informative SNPs. Comparison of a set …

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Student-Focused Learning Programs: Designing And Delivering, Susan A. Ariew, Matt Torrence Mar 2012

Student-Focused Learning Programs: Designing And Delivering, Susan A. Ariew, Matt Torrence

Academic Services Faculty and Staff Publications

Librarians typically have limited time during one-shot library instruction sessions, so supplementing instruction with asynchronous reusable learning objects (videos, tutorials, Prezi presentations, LibGuides, etc) allows them to maximize their time with students in all environments. Embedded librarian, Susan Ariew, will illustrate the reusable learning objects she uses in course management systems to prepare students for classes to get them beyond the basics and prime them for meaningful librarian/student instructional sessions. From in-studio production to laptop simplicity, we've tried it all in terms of video instruction. Engineering & Business Librarian Matt Torrence will talk about the production side of things, illustrating …

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Increasing Reliability Of A Small 2-Stroke Internal Combustion Engine For Dynamically Changing Attitudes, Steven C. Crosbie Mar 2012

Increasing Reliability Of A Small 2-Stroke Internal Combustion Engine For Dynamically Changing Attitudes, Steven C. Crosbie

Theses and Dissertations

Remotely Piloted Aircraft (RPA) typically utilize commercial internal combustion engines (ICE) as their power sources. These engines are designed to run at sea level, but these aircraft are often pressed into service at higher altitudes where the performance characteristics deteriorate. A Brison 95cc two-stroke engine's performance characteristics at altitude are investigated using a test facility that can measure these characteristics over a range of pressures and temperatures. With its stock carburetor at sea level static (SLS) conditions, the engine makes 5.5 peak horsepower (hp) and brake specific fuel consumption (BSFC) ranged from 1.2-4.0 lb/(hp-hr). At 10,000 feet conditions, the peak …

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Removing 17Β-Estradiol From Drinking Water In A Biologically Active Carbon (Bac) Reactor Modified From A Granular Activated Carbon (Gac) Reactor, Zhongtian Li Mar 2012

Removing 17Β-Estradiol From Drinking Water In A Biologically Active Carbon (Bac) Reactor Modified From A Granular Activated Carbon (Gac) Reactor, Zhongtian Li

Z Li

Estrogenic compounds in drinking water sources pose potential threats to human health. Treatment technologies are needed to effectively remove these compounds for the production of safe drinking water. In this study, GAC adsorption was first tested for its ability to remove a model estrogenic compound, 17β-estradiol (E2). Although GAC showed a relatively high adsorption capacity for E2 in isotherm experiments, it appeared to have a long mass transfer zone in a GAC column reactor, causing an early leakage of E2 in the effluent. With an influent E2 concentration of 20 μg/L, the GAC reactor was able to bring down effluent …

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Differential Effects Of Ovariectomy On The Mechanical Properties Of Cortical And Cancellous Bone In Rat Femora And Vertebrae, Debbie Chachra, J.M. Lee, M. Kasra, Marc Grynpas Mar 2012

Differential Effects Of Ovariectomy On The Mechanical Properties Of Cortical And Cancellous Bone In Rat Femora And Vertebrae, Debbie Chachra, J.M. Lee, M. Kasra, Marc Grynpas

Debbie Chachra

The purpose of this study was to evaluate the effects of ovariectomy on the mechanical properties of bone in the aged Sprague-Dawley rat model of osteoporosis. Eight female rats were sacrificed at the start of the study, at the age of four months. Twenty-four remaining rats were then bilaterally ovariectomized (OVX), and another twenty-four served as controls. Eight rats from each group were sacrificed at five, ten or fifteen weeks. The mean density of L1 vertebral bodies from OVX rats was lower than in their control counterparts, as was the compressive modulus, the ultimate compressive stress and the toughness. The …

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Bone Quality In Animal Models Of Osteoporosis, Marc Grynpas, Debbie Chachra, Kathleen Lundon Mar 2012

Bone Quality In Animal Models Of Osteoporosis, Marc Grynpas, Debbie Chachra, Kathleen Lundon

Debbie Chachra

The use of animal models is a very powerful tool for the preclinical assessment of potential therapies for osteoporosis. However, the effective use of animal models has two prerequisites. The first is the use of appropriate techniques to assess the overall effects of therapy on bone. As spontaneous fractures do not occur in any species other than humans, the efficacy of a therapy cannot be assessed by its impact on fracture incidence. Instead, a suite of parameters (collectively referred to as ‘bone quality’), including bone architecture, mineralization and mechanical properties, is examined. While techniques such as histomorphometry and dual-energy x-ray …

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Biomaterial–Microvasculature Interactions, Alisha L. Sarang-Sieminski, Keith J. Gooch Mar 2012

Biomaterial–Microvasculature Interactions, Alisha L. Sarang-Sieminski, Keith J. Gooch

Alisha L. Sarang-Sieminski

The utility of implanted sensors, drug-delivery systems, immunoisolation devices, engineered cells, and engineered tissues can be limited by inadequate transport to and from the circulation. As the primary function of the microvasculature is to facilitate transport between the circulation and the surrounding tissue, interactions between biomaterials and the microvasculature have been explored to understand the mechanisms controlling transport to implanted objects and ultimately improve it. This review surveys work on biomaterial–microvasculature interactions with a focus on the use of biomaterials to regulate the structure and function of the microvasculature. Several applications in which biomaterial–microvasculature interactions play a crucial role are …

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Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter Mar 2012

Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter

USF Tampa Graduate Theses and Dissertations

A simple anaerobic digestion model has been developed for a continuously-stirred tank reactor (CSTR), which links the specific biogas production rate to the food/microorganism ratio (F/M). The model treats the various microbial populations involved in the sequential biological processes involved in anaerobic digestion as a composite and links the entire biomass specific growth rate directly to the specific biogas production rate. The model was calibrated by determining the specific gas production rate for a range of F/M values using a municipal wastewater seed sludge. The model predictions for steady-state biogas production rates were compared to observed biogas production and volatile …

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Evaluation Of The Thorax Of Manduca Sexta For Flapping-Wing Micro Air Vehicle Applications, Alex C. Hollenbeck Mar 2012

Evaluation Of The Thorax Of Manduca Sexta For Flapping-Wing Micro Air Vehicle Applications, Alex C. Hollenbeck

Theses and Dissertations

The tobacco hornworm hawkmoth (Manduca sexta) provides an excellent model from which to garner knowledge pertaining to the development of a Flapping Wing Micro Air Vehicle (FWMAV). Insect-sized FWMAVs will be used by the future warfighter for reconnaissance, nuclear/chemical/biological hazard sensing, and targeting. One of the major challenges facing FWMAV developers is the energetically demanding nature of low Reynolds flapping flight. Investigating the Manduca sexta thorax/wing flapping mechanism as a mechanical system will provide insight into its inherent efficiency. This thesis examined the energetics of the thorax under static loading and dynamic loading using an innovative load-application technique. It was …

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An Experimental Study Of The Active Control Of A Building Model, Isao Nishimura, A.M. Abdel-Ghaffar, Sami Masri, Richard Miller, J.L. Beck, T.K. Caughey, W.D. Iwan Mar 2012

An Experimental Study Of The Active Control Of A Building Model, Isao Nishimura, A.M. Abdel-Ghaffar, Sami Masri, Richard Miller, J.L. Beck, T.K. Caughey, W.D. Iwan

Richard K. Miller

This paper reports some of the results of an ongoing analytical and ex perimental study into the control of building-like structures subjected to nonstationary ran dom excitations such as earthquakes. The structural model used resembles a 5-story build ing about 2.5 meters high. The building model was subjected to a variety of direct-force excitations. The control algorithm used employs an adaptive structural member at a prede termined location in the model in order to attenuate the structural response relative to the moving building foundation. An electromagnetic actuator is used to generate the required control faces in the "smart" member. Among …

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Combat Identification Of Synthetic Aperture Radar Images Using Contextual Features And Bayesian Belief Networks, John X. Situ Mar 2012

Combat Identification Of Synthetic Aperture Radar Images Using Contextual Features And Bayesian Belief Networks, John X. Situ

Theses and Dissertations

Given the nearly infinite combination of modifications and configurations for weapon systems, no two targets are ever exactly the same. Synthetic Aperture Radar (SAR) imagery and associated High Range Resolution (HRR) profiles of the same target will have different signatures when viewed from different angles. To overcome this challenge, data from a wide range of aspect and depression angles must be used to train pattern recognition algorithms. Alternatively, features invariant to aspect and depression angle must be found. This research uses simple segmentation algorithms and multivariate analysis methods to extract contextual features from SAR imagery. These features used in conjunction …

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Impact Of Self-Reported Biases And Familiarity In A Baggage Screening Context, Scott W. Halwes Mar 2012

Impact Of Self-Reported Biases And Familiarity In A Baggage Screening Context, Scott W. Halwes

Theses and Dissertations

A common assumption is that items that evoke strong emotions are more easily recognized than items that do not evoke strong emotions (Bessette-Symons, 2008). For example, items such as guns or knives may evoke strong emotions within some people, and it may be presumed that these items may be more easily recognized by people that have strong emotions associated with them. If this is true, then perhaps these people would be more apt to locate these items in situations such as baggage screening services that rely on accurate detection of weapons for the public's safety. This study explores this reasoning …

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Tanker Fuel Consolidation: Effects Of Higher Fidelity Modeling On A Resilient Plan, Jason A. Larimore Mar 2012

Tanker Fuel Consolidation: Effects Of Higher Fidelity Modeling On A Resilient Plan, Jason A. Larimore

Theses and Dissertations

The U.S. Air Force (USAF) has selected the KC-46 to begin replacing the aged KC-135 fleet. One of the major differences between the KC-46 and the KC-135 is the KC-46's ability to be refueled. This allows for tanker fuel consolidation, or the refueling of one tanker by another. The effects of this capability on the efficiency of tanker operations must be quantified and included in determining an appropriate substitution ratio between the two aircraft. This ratio will be used to plan the retirement of KC-135s as the KC-46 enters operational fielding. This study utilizes simulation to determine the efficiencies gained …

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Air-To-Air Missile Enhanced Scoring With Kalman Smoothing, Jonathon S. Gipson Mar 2012

Air-To-Air Missile Enhanced Scoring With Kalman Smoothing, Jonathon S. Gipson

Theses and Dissertations

A correct estimate of a missile's flight path is essential to USAF test and evaluation efforts. The USAF air-to-air Weapons System Evaluation Program (WSEP) targets unmanned aerial drones in hundreds of live-fire missile tests each year. The current QF-4 drone inventory is expected to be depleted by 2015. The QF-16 Full Scale Aerial Target (FSAT) contract has been awarded to convert usable early model F-16s into remote-controlled drones. The QF-16 will provide a highly-maneuverable, realistic testing environment for 5th generation fighters. To accomplish their mission, WSEP requires a scoring system capable of estimating the trajectory of a missile relative to …

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A High Bandwidth Non-Destructive Method For Characterizing Simple Media, Matthew L. Szuster Mar 2012

A High Bandwidth Non-Destructive Method For Characterizing Simple Media, Matthew L. Szuster

Theses and Dissertations

The relative complex permittivity can be extracted with time domain data from a perfect electrical conductor (PEC) backed sample of a low-loss, non-dispersive dielectric using dual ridged waveguide aperture probes with attached PEC flange plates of the same geometry and different dimensions. The temporal domain measurement of interest is the ability to detect the reflection from the edge of the flange plate in the parallel region created by the flange plate and the PEC backing on the dielectric sample. Signal processing windows are applied to the data in order to exploit this edge reflection. The types of signal processing methods …

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An Inquiry: Effectiveness Of The Complex Empirical Mode Decomposition Method, The Hilbert-Huang Transform, And The Fast-Fourier Transform For Analysis Of Dynamic Objects, Kristen L. Wallis Mar 2012

An Inquiry: Effectiveness Of The Complex Empirical Mode Decomposition Method, The Hilbert-Huang Transform, And The Fast-Fourier Transform For Analysis Of Dynamic Objects, Kristen L. Wallis

Theses and Dissertations

A review of current signal analysis tools show that new techniques are required for an enhanced fidelity or data integrity. Recently, the Hilbert-Huang transform (HHT) and its inherent property, the Empirical Mode Decomposition (EMD) technique, have been formerly investigated. The technique of Complex EMD (CEMD) was also explored. The scope of this work was to assess the CEMD technique as an innovative analysis tool. Subsequent to this, comparisons between applications of the Hilbert transform (HT) and the Fast-Fourier transform (FFT) were analyzed. MATLAB was implemented to model signal decomposition and the execution of mathematical transforms for generating results. The CEMD …

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A Prototype Overview For Allocating Usaid Foreign Aid, Deane E. Cover Mar 2012

A Prototype Overview For Allocating Usaid Foreign Aid, Deane E. Cover

Theses and Dissertations

The United States Agency for International Development (USAID) is the federal government agency primarily responsible for administering civilian foreign aid. In fiscal year 2011, USAID spent approximately $15 billion in an effort to assist countries recovering from disaster, trying to escape poverty, and engaging in democratic reforms. Using Value-Focused Thinking, regression, and optimization techniques, this thesis utilizes overarching USAID objectives and underlying policy to develop a prototype overview model that is used to provide insight to a Decision Maker regarding how changes in funding allocation can lead to improved impact.

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Hybrid Bioreactor For Reduction Of Capital Costs, David J. Bayless Mar 2012

Hybrid Bioreactor For Reduction Of Capital Costs, David J. Bayless

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A bioreactor with first and second containers has translucent sidewalls housing a plurality of planar membranes over which a slurry of water and photosynthetic microorganisms flows. A light collector is mounted adjacent a gap between the first and second containers for receiving incident light and conveying the light through optical waveguides, such as fibers, to distributors. The distributors are mounted in the first and second containers near a lower end of the substrates so that photons incident on the optical waveguides are conveyed through the optical waveguides to the light distributors and then to the lower ends of the substrates …

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Optimization Of Nanoscale Zero-Valent Iron For The Remediation Of Groundwater Contaminants, Andrew W. E. Mcpherson Mar 2012

Optimization Of Nanoscale Zero-Valent Iron For The Remediation Of Groundwater Contaminants, Andrew W. E. Mcpherson

Theses and Dissertations

Nanoscale zero-valent iron (nZVI) is an emerging tool for the remediation of groundwater contaminants. The nanoparticles are capable of reductively destroying or immobilizing a wide range of contaminants. Their small size results in a high surface area to mass ratio, making them much more reactive compared to their more-coarse predecessors. Small particle size also allows nZVI particles to be injected directly into contaminated areas via a well, limiting the above-ground footprint and allowing access to contaminated areas that are beyond the reach of some conventional methods. nZVI technology has the potential to facilitate remediation in difficult situations, improve remediation outcomes, …

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