Digital Commons Network^™

Modeling And Computational Framework For The Specification And Simulation Of Large-Scale Spiking Neural Networks, David James Herzfeld

Master's Theses (2009 -)

Recurrently connected neural networks, in which synaptic connections between neurons can form directed cycles, have been used extensively in the literature to describe various neurophysiological phenomena, such as coordinate transformations during sensorimotor integration. Due to the directed cycles that can exist in recurrent networks, there is no well-known way to a priori specify synaptic weights to elicit neuron spiking responses to stimuli based on available neurophysiology. Using a common mean field assumption, that synaptic inputs are uncorrelated for sufficiently large populations of neurons, we show that the connection topology and a neuron's response characteristics can be decoupled. This assumption allows …

Adaptive Real-Time Decoding Of Brain Signals For Long-Term Control Of A Neuro-Prosthetic Device, Tushar Ashok Dharampal

Master's Theses (2009 -)

Changes in the statistical properties of neural signals recorded at the brain machine interface (BMI) pose significant challenges for accurate long-term control of prostheses interfaced directly with the brain by continuously altering the relationship between neural responses and desired action. In this thesis, we develop and test an adaptive decoding algorithm that can recover from changes in the statistical properties of neural signals within minutes. The adaptive decoding algorithm uses a Kalman filter as part of a dual-filter design to continuously optimize the relationship between the observed neural responses and the desired action of the prosthesis. Performance of the algorithm …

Tools For Creating Wide-Field Views Of The Human Retina Using Optical Coherence Tomography, Ashavini M. Pavaskar

Master's Theses (2009 -)

Optical Coherence Tomography (OCT) has allowed in-vivo viewing of details of retinal layers like never before. With the development of spectral domain OCT (SD-OCT) details of nearly 2µm axial resolution and higher imaging speed have been reported. Nevertheless, a single volume scan of the retina is typically restricted to 6mm x 6mm in size. Having a larger field of view of the retina will definitely enhance the clinical utility of the OCT.

A tool was developed for creating wide-field thickness maps of the retina by combining the use of already available tools like i2k Retina (DualAlign, LLC, Clifton Park, NY) …

Comparing Fbg And Pcf Force Sensors In A Laparoscopic Smart Surgical Scissor Instrument, Dean Callaghan, Ginu Rajan, Mark Mcgrath, Eugene Coyle, Yuliya Semenova, Gerald Farrell

Conference Papers

This paper presents a sensorized laparoscopic surgical scissor instrument using both a fiber Bragg grating (FBG) and a tapered photonic crystal fiber (PCF) as force sensors. The sensors are located on the blades for the detection of interaction forces generated between the instrument and tissue during cutting. The force sensitivity of each sensorized blade is examined. Results show that the scissor blade-PCF sensor arrangement outperforms the blade with the FBG during static loading calibration experimentation. Moreover, experiments show that the PCF based arrangement is less sensitive to temperature effects than its FBG counterpart. This negates the need for additional temperature …

Integration Of Micropore And Nanopore Features With Optofluidic Waveguides For Single Particle Sensing, Matthew R. Holmes

Theses and Dissertations

This dissertation outlines the research and development of ground-breaking nanometer sized openings (nanopores) integrated with an on-chip optofluidic platform. This platform represents a significant advancement for single nanoparticle sensing. In this work specifically, the integrated optofluidic platform has been used to electrically and optically filter and detect single nanoparticles using ionic current blockade and fluorescence experiments. The correlation of electrical and optical signal has provided the highest sensitivity single nanoparticle measurements ever taken with integrated optofluidic platforms. The particular optofluidic platform used for this work is an antiresonant reflecting optical waveguide (ARROW). ARROW hollow and solid core waveguides are interference …

Devices And Methods For Electro-Physical Transport Of Dna Across Cell Membranes, Quentin Theodore Aten

Theses and Dissertations

A novel method for charged macromolecule delivery, called nanoinjection, has been developed at Brigham Young University. Nanoinjection combines micro-fabrication technology, mechanism design, and nano-scale electrical phenomenon to transport exogenous DNA across cell membranes on a nano-featured lance. DNA is electrically accumulated on the lance, precision movements of microelectromechanical systems (MEMS) physically insert the lance into cell, and DNA is electrically released from the lance into the cell. Penetration into the cell is achieved through a two-phase, self-reconfiguring metamorphic mechanism. The surface-micromachined, metamorphic nanoinjector mechanism elevates the lance above the fabrication substrate, then translates in-plane at a constant height as the …

Effect Of Freshman Chemistry On Student Performance In Sophomore Engineering Courses, Michael A. Collura, Shannon Ciston, Nancy Ortins Savage

Chemistry and Chemical Engineering Faculty Publications

The role of first year chemistry courses in engineering programs varies somewhat across programs and disciplines. Clearly most engineering majors will encounter chemistry topics of a general nature in some of their upper-level course work. The purpose of requiring chemistry in the first year, however, goes well beyond learning chemical concepts. As a quantitative science, chemistry requires the use of math, principally algebra, on a regular basis in solving various problems. Students should gain an appreciation of the importance of units in solving problems should come to understand the difference between implicit and explicit properties and should develop other quantitative …

A New Model Of Project Based Learning, Ron Ulseth, Jefferey E. Froyd, Thomas A. Lotzinger, Dan Ewert, Bart Johnson

Integrated Engineering Department Publications

A new model for engineering education has been developed and funded. The model is 100% project based learning (PBL) where the students develop their own learning objectives. The projects are authentic needs contributed by collaborating industries. Students monitor the acquisition of 32 technical competencies and all of the design and professionalism competencies required of new practicing engineers. The reasons for the new model, description of the model, research supporting the model, methods for evaluating the model and its transportability are discussed.

The 4+1 Program And Distance Learning Meeting Objectives And Outcomes, Daniel W. Walsh, Lanny Griffin, Robert S. Crockett

Biomedical Engineering

Graduate engineering education is a key to the maintenance of U.S. competitiveness in the world market. The world has been an extremely dynamic engine during the last fifty years, and we have witnessed a dramatic change in the world order. The change has been evolutionary in many cases, but events in Eastern Europe, the Middle East and the erstwhile Soviet Union are only slightly less cataclysmic than the Second World War. In a world where strength is measured in terms of the financial resource, the technological ability and the intellectual capability of a populace Japan, China, India and the EEC …

Review Of Gasoline, Diesel, And Ethanol Biofuels From Grasses And Plants, By Ram B. Gupta And Ayhan Demirbas., Adam J. Liska

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A new book on the production of biofuels by Gupta and Demirbas provides technical insight into the conversion processes that could provide a range of domestic fuels from plant materials to substitute for foreign oil. It focuses primarily on conversion processes for production of cellulosic ethanol, Fischer-Tropsch diesel, pyrolysis bio-oil, and hydrothermal biocrude from biomass resources, as well as "first-generation" grain ethanol and biodiesel from vegetable oil. In addition to a detailed summary of these chemical processes, the book provides a briefer treatment of related matters such as biofuel policy, economics, and environmental issues.

Drought Regionalization Of Brazos River Basin Using An Entropy Approach, Deepthi Rajsekhar, Ashok Mishra, Vijay P. Singh

2011 Symposium on Data-Driven Approaches to Droughts

Assessment and understanding of past climate is an important step for drought mitigation and water resources planning. In this study, stream flows imulation obtained from the variable infiltration capacity(VIC) model was used for drought characterization, and subsequently regionalization was done based on the annual severity level, for the Brazos basin in Texas over a time span of 1949-2000. It is important to study drought characteristics with in a regional context. Hence, identification of homogenous drought regions is a prerequisite, so that the drought characteristics can be studied with in each of these regions. In this study, the concept of entropy …

A Look At 20th Century Droughts, Vijay P. Singh, Ashok K. Mishra

2011 Symposium on Data-Driven Approaches to Droughts

Droughts exercise a profound effect on the social and economic fabric of nations. Many nations of the world experienced droughts encompassing the full spectrum of severity, areal extent and duration. The result has been that the economic development was hampered and many countries have not yet recouped fully from the ravages of droughts. The first decade of the 21st century has also witnessed varying degrees of droughts across the globe. Therefore, we ask the following questions: (a) Do droughts affect every part of the world? (b) Are there similarities in major droughts around the world? (c) Are climate change and …

Surgical Cutting And Ablation By Energy Based Devices: Principles And Applications, Garrett Mcguinness, Joseph A. Mcgeough, Graham Gavin, Brendan O'Daly

Conference Papers

Advances in ultrasound, radiofrequency, and water jet systems are facilitating their increased use in new medical ablation or cutting applications in fields as diverse as cardiology, orthopaedics, ophthalmology, dermatology, oncology and neurosurgery. These methods involve controlled alteration or destruction of tissues via the application of thermal, electrical or kinetic energy. This market segment is characterised by advanced devices capable of heating or cooling tissue from -200°C to 400°C, or inducing vibrations of up to 60 kHz to cause tissue damage. The medical conditions targeted primarily pertain to chronic and age-related diseases, but elective and cosmetic procedures are also addressed. Medical …

Optimization Of A Tri-Layered Vascular Graft: The Influence Of Cellular And Mechanical Properties, Michael Mcclure

Theses and Dissertations

Electrospinning is a polymer processing technique which allows for the production of nano to micro size fibers and scaffolds which can be composed of numerous synthetic biodegradable materials and natural biopolymers. Natively, elastin and collagen are the main components of vascular tissue. Arranged in a tri-layered structure, they create a specific mechanical environment that can withstand the rigors of circulation. The goal of this study was to develop a mechanically ‘biomimicking’ vascular graft composed of three distinct layers through the process of electrospinning. We hypothesize that the use of bioactive agents such as elastin, collagen, and silk to supplement poly(caprolactone) …

The Effect Of Adding Organic Polymers To Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. Coughlan, N. M. Cummins, A. W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

To conclude, the addition of polymers to GPCs resulted in little change to the Tw and Ts, however the compressive strength was found to decrease slightly. ASAP tests revealed that the cements may undergo some structural changes as a result of these additions. In the future perhaps the addition of organic polymers suspended in the liquid phase as part of the cement may yield improved results in this type of study. © 2011 IEEE.

Solar Warning Architecture For Manned Missions To Mars, James S. Bohren, John K. Howard

Theses and Dissertations

Solar radiation storms represent a dire threat to manned interplanetary space travel. Earth's current solar forecasting architecture is Earth-focused and insufficient to provide timely warnings to a manned mission to Mars, therefore a "best value" solar warning architecture must be identified. A total of 14 solar warning architectures were developed by varying 5 solar sensor locations, 2 processing locations, and 2 communications strategies. Using Satellite Tool Kit, performance of the candidate architectures in terms of Warning Time and Solar Coverage was quantified during a Mars mission scenario based on NASA's Design Reference Architecture 5.0. Cost of each candidate architecture was …

Design And Characterization Of A Space Based Chromotomographic Hyperspectral Imaging Experiment, Jason D. Niederhauser

Theses and Dissertations

This research focuses upon the design, analysis and characterization of several systems related to a spacebased chromotomographic experiment (CTEx), a hyperspectral imager, currently in development at the Air Force Institute of Technology. Three interrelated subject-areas were developed. The initial focal point was a generic, system-level mechanical layout and integration analysis of the space-based instrument. The scope of this work was intended to baseline the space-based system design in order to allow for further trade-space refinement and requirements development. Second, development of an iteration upon the ground-based version of CTEx was accomplished in an effort to support higher-fidelity field data-collection. This …

Determination Of Ibuprofen Isotherm Using Supercritical Fluid Chromatography, Loi Ho

USF Tampa Graduate Theses and Dissertations

Chromatography is widely used to determine physiochemical properties data including adsorption isotherm. In the separation of enantiomers through sorptive processes, supercritical fluids allow efficient and green alternatives to liquid solvent based systems. The isotherm information is vital in the development of operating policies and design of preparative chromatographic or moving bed separation schemes. Determination of sorption isotherms from experimental chromatographic elution data is automated and compared with different chromatogram model. Procedures were developed and validated for separation of R- and S- ibuprofen with supercritical 〖CO〗_2 and ethanol mixture as the mobile phase over a chiral stationary phase. The isotherms for …

Use Of Remote Sensing To Support Forest And Wetlands Policies In The Usa, Audrey L. Mayer, Ricardo D. Lopez

College of Forest Resources and Environmental Science Publications

The use of remote sensing for environmental policy development is now quite common and well-documented, as images from remote sensing platforms are often used to focus attention on emerging environmental issues and spur debate on potential policy solutions. However, its use in policy implementation and evaluation has not been examined in much detail. Here we examine the use of remote sensing to support the implementation and enforcement of policies regarding the conservation of forests and wetlands in the USA. Specifically, we focus on the “Roadless Rule” and “Travel Management Rules” as enforced by the US Department of Agriculture Forest Service …

Behavior Of Na+-Polystyrene Sulfonate At The Interface With Single-Walled Carbon Nanotubes (Swnts) And Its Implication To Swnt Suspension Stability, Tabbetha A. Dobbins, Richard Chevious, Yuri Lvov

College of Science & Mathematics Departmental Research

The assembly of sodium polystyrene sulfonate (Na+-PSS) at the surface of single-walled carbon nanotubes (SWNTs) in pH 3 aqueous solution is described. Rather than forming linear or sheet-like chain morphologies over SWNT surfaces, Na+-PSS adopts a spherically collapsed conformation believed to be the result of cation (either Na+ or H+) condensation onto the ionized polymer chain. It is well reported that cations (and also anions) adsorb preferentially onto single-walled and multi-walled carbon nanotube surfaces leading to an increased ion concentration in the near surface regions relative to the bulk solution. This work provides experimental evidence for preferentially absorbed cation condensation …

Filling The Gap: Commonsense Solutions For Meeting Front Range Water Needs: Executive Summary, Western Resource Advocates, Trout Unlimited, Colorado Environmental Coalition (U.S.)

Navigating the Future of the Colorado River (Martz Summer Conference, June 8-10)

8 pages.

"February 2011"

Presented by Drew Beckwith, Water Policy Manager, Western Resource Advocates, on June 10th at Clyde O. Martz Summer Conference 2011, Navigating the Future of the Colorado River Basin

Full report available at: http://www.westernresourceadvocates.org/gap

Temperature Control Device With A Flexible Temperature Control Surface, Phil D. Belgrader, Christopher G. Cooney, Robert D. Doebler, Anna D. Hickerson, Bruce D. Irvine, Ali D. Nadim, James D. Sterling, Reza Miraghale

Business and Information Technology Faculty Research & Creative Works

A device for controlling temperature in a reaction chamber is disclosed. The device comprises: a bladder assembly comprising a housing dimensioned to hold a reaction chamber disposed within an interior Volume of the housing; and a first temperature-control bladder disposed within the housing, the first temperature-control bladder is configured to receive a temperature-control fluid and comprises a flexible, heat conductive Surface that comes in contact with at least a portion of an exterior surface of the reaction chamber after receiving the temperature-control fluid. Also disclosed are a bladder thermal cycler, a temperature-control bladder assembly and methods for producing a thermal …

Use Of Imaging Biomarkers To Assess Perfusion And Glucose Metabolism In The Skeletal Muscle Of Dystrophic Mice, Nabeel Ahmad, Ian Welch, Robert Grange, Jennifer Hadway, Savita Dhanvantari, David Hill, Ting-Yim Lee, Lisa M Hoffman

Robarts Imaging Publications

BACKGROUND: Duchenne muscular dystrophy (DMD) is a severe neuromuscular disease that affects 1 in 3500 boys. The disease is characterized by progressive muscle degeneration that results from mutations in or loss of the cytoskeletal protein, dystrophin, from the glycoprotein membrane complex, thus increasing the susceptibility of contractile muscle to injury. To date, disease progression is typically assessed using invasive techniques such as muscle biopsies, and while there are recent reports of the use of magnetic resonance, ultrasound and optical imaging technologies to address the issue of disease progression and monitoring therapeutic intervention in dystrophic mice, our study aims to validate …

Radio Frequency Identification Classroom Management System, Andrew W. Wright

Industrial and Manufacturing Engineering

Professors who manage large classes are unrealistically expected to grade each student fairly and accurately. Even with all of the technological advancements that have occurred in the past thirty years, very little progress has been made in classroom management, and as a result, professors are not equipped with enough tools to successfully manage large class sizes. Because radio frequency identification (RFID) technology is making its way into student issued identification cards, there is an opportunity to use it as a tool to aid professors in the classroom. The focus of this paper is to discover an effective system that can …

Determining A Method For Rendering Low Cost Cdse(Zns) Core(Shell) Quantum Dots Aqueous Soluble Via Amphiphilic Polymer Wrapping, Patrick Mcbride

Materials Engineering

Herein is described the procedure of two amphiphilic polymer wrapping techniques that may be employed for obtaining aqueous soluble quantum dots (QDs) for use in biological fluorescent imaging applications. The advent of QDs has led to new nanoscale fluorescent materials that exhibit unparalleled quantum yields (QYs), high resistance to photobleaching, tunable emissions, and
absorption over a large optical range. However, the QD synthesis employed here at Cal Poly to obtain bright, photostable CdSe(ZnS) core(shell) QDs involves the use of organic solvents and surfactants, leading to hydrophobic QDs. Since all of biology relies on aqueous solubility, this hydrophobicity creates a major …

Artificial Muscle Project: Process Development Of Polydimethyl Siloxane Thin Films For Use In Dielectric Electroactive Polymer Artificial Muscle Actuators, Vincent J. Gayotin, Richard W. Morrison, Paul A. Preisser

Materials Engineering

An artificial muscle design was created founded on the principles of a dielectric electroactive polymer (DEAP), which is fundamentally similar to a capacitor. A polydimethyl siloxane (PDMS)-based elastomer, Sylgard 184 from Dow Corning, was chosen for the design and spun coat onto polystyrene (PS) Petri dishes at varying speeds to create a thin film, using speeds of 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm, and 6000 rpm. The film thicknesses were measured optically through use of a microscope with coupled computer imaging software to generate a characteristic curve of film thickness to spin speed, achieving a minimum film thickness …

Auto Fall Detector, Nhut Thanh Ho

Computer Engineering

This device is named Cardea, the goddess of health in roman Mythology. The Cardea will be attached to the waist of the individual’s body to detect any falls, and will send out alarm signals to people in the surrounding area. The end goal of this project is to provide a helpful and friendly device for the elderly and their families. It is easy to maintain and dependable for long term use.

Heart-Rate Monitoring Control System Using Photoplethysmography (Ppg), Wesley Nguyen, Ryan Horjus

Electrical Engineering

No abstract provided.

The Design And Manufacture Of A Microfluidic Reactor For Synthesis Of Cadmium Selenide Quantum Dots Using Silicon And Glass Substrates, Peter Gonsalves

Materials Engineering

A microfluidic reactor for synthesizing cadmium selenide (CdSe) quantum dots (QDs) was synthesized out of silicon and Pyrex glass. Microfabrication techniques were used to etch the channels into the silicon wafer. Holes were wet-drilled into Pyrex glass using a diamond-tip drill bit. The Pyrex wafer was aligned to the etched silicon wafer and both were anodically bonded to complete the microfluidic reactor. Conditions for anodic bonding were created by exposing the stacked substrates to 300V at ~350^oC under 5.46N of force.  Bulk CdSe solution was mixed at room temperature and treated as a single injection. The syringe containing …

Piedras Blancas Light Station Vista Point Improvement Plan, Larissa Heeren, Reuben Juster, Annamarie Usher, John Rossi, Nick Mitchell

Mechanical Engineering

Piedras Blancas Light station Improvement Involved the design of two separate parking lot/vista point plans as well as the creation of a concrete Iron Ranger located near the gift shop on site.