Engineering Commons^™

Arterial Waveform Measurement Using A Piezoelectric Sensor, Ruizhi Zhang

Theses and Dissertations

This study aims to develop a new method to monitor peripheral arterial pulse using a PVDF piezoelectric sensor. After comparing different locations of sensor placement, a specific sensor wrap for the finger was developed. Its composition, size, and location make it inexpensive and very convenient to use. In order to monitor the effectiveness of the sensor at producing a reliable pulse waveform, a monitoring system, including the PZT sensor, ECG, pulse-oximeter, respiratory sensor, and accelerometer was setup. Signal analysis from the system helped discover that the PZT waveform is relative to the 1st derivative of the artery pressure wave. Also, …

Simulation Of Sub-Micron Thermal Transport In A Mosfet Using A, James Loy, Druv Singh, Jayathi Y. Murthy

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

Self-heating has emerged as a critical bottleneck to scaling in modern transistors. In simulating heat conduction in these devices, it is important to account for the granularity of phonon transport since electron-phonon scattering occurs preferentially to select phonon groups. However, a complete accounting for phonon dispersion, polarization and scattering is very expensive if the Boltzmann transport equation (BTE) is used. Moreover, difficulties with convergence are encountered when the phonon Knudsen number becomes small. In this paper we simulate a two-dimensional bulk MOSFET hotspot problem using a partially-implicit hybrid BTE-Fourier solver which is significantly less expensive than a full BTE solution, …

Beyond Ning: Rolling Your Own Social Network, Aaron Sumner

SIDLIT Conference

Ning has recently announced plans to discontinue its free service, requiring network creators to pay for service or leave Ning altogether. In this session we'll look at how this decision affects educational users of Ning, as well as alternative, DIY social networking software packages such as Elgg, Buddypress, and Community Engine.

Growth And Characterization Of Non-Polar Gan Materials And Investigation Of Efficiency Droop In Ingan Light Emitting Diodes, Xianfeng Ni

Theses and Dissertations

General lighting with InGaN light emitting diodes (LEDs) as light sources is of particular interest in terms of energy savings and related environmental benefits due to high lighting efficiency, long lifetime, and Hg-free nature. Incandescent and fluorescent light sources are used for general lighting almost everywhere. But their lighting efficiency is very limited: only 20-30 lm/W for incandescent lighting bulb, approximately 100 lm/W for fluorescent lighting. State-of-the-art InGaN LEDs with a luminous efficacy of over 200 lm/W at room temperature have been reported. However, the goal of replacing the incandescent and fluorescent lights with InGaN LEDs is still elusive since …

An Adaptive Grid-Based All Hexahedral Meshing Algorithm Based On 2-Refinement, Jared D. Edgel

Theses and Dissertations

Adaptive all-hexahedral meshing algorithms have many desirable features. These algorithms provide a mesh that is efficient for analysis by providing a high element density in specific locations, such as areas of high stress gradient or high curvature and reduced mesh density in other areas of less importance. In addition, inside-out hexahedral grid based schemes, using Cartesian structured grids for the base mesh, have shown great promise in accommodating automatic all-hexahedral algorithms. In these algorithms mesh refinement is generally used to capture geometric features. Unfortunately, most adaptive mesh generation algorithms employ a 3-refinement method. This method, although easy to employ, provides …

Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes …

Equilibrium Studies For The Removal Of Basic Dye By Sunflower Seed Husk (Helianthus Annuus), Siew-Teng Ong, Pei-Sin Keng, Siew-Ling Lee, Ming-How Leong, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

The sorption characteristics of sunflower (Helianthus annuus) seed husk (SSH) to remove Methylene Blue (MB) from aqueous solution under batch conditions have been investigated. Sorption of MB was found to be pH, concentration and agitation dependent. The kinetics of sorption was rapid with 80% sorption taking place within the first 60 min regardless of its initial concentration. The fast attainment of equilibrium implying the biosorbent could be suitable for continuous flow system. Using the pseudosecond order kinetics model, the predictive model for MB sorbed at time t (qt) with the initial concentration of (Co) is given by qt = Cot/[0.0607Co …

The Other Gulf Oil Crisis - In Southwest Asia, Adam Liska

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The oil spill in the Gulf of Mexico is a rude reminder of the risks inherent in an economy dependent upon petroleum. But there's a quieter crisis in the other gulf - the Persian Gulf - that should call Americans' attention to the even more severe consequences of relying upon imported oil. The costs of using the military to protect the transport of oil from the most turbulent part of the world should convince our country's policymakers to increase investments in researching and developing affordable, American-made clean-burning alternative fuels. But, first, we have to understand the real causes, costs and …

Polyurethane-Based Polymer Surface Modifiers With Alkyl Ammonium Co-Polyoxetane Soft Blocks: Reaction Engineering, Surface Morphology And Antimicrobial Behavior, Kennard Brunson

Theses and Dissertations

Concentrating quaternary (positive) charge at polymer surfaces is important for applications including layer-by-layer polyelectrolyte deposition and antimicrobial coatings. Prior techniques to introduce quaternary charge to the surface involve grafting of quaternary ammonium moieties to a substrate or using polyurethanes with modified hard segments however there are impracticalities involved with these techniques. In the case of the materials discussed, the quaternary charge is introduced via polyurethane based polymer surface modifiers (PSMs) with quaternized soft segments. The particular advantage to this method is that it utilizes the intrinsic phase separation between the hard and soft segments of polyurethanes. This phase separation results …

Real Time 3-D Tracking Of The High Dose Rate Radiation Source Using A Flat Panel Detector, Aditya Bondal

Theses and Dissertations

A number of QA procedures have been developed for Breast Brachytherapy treatments, yet none guarantee accurate dose delivery or allow conformation of the actual source position leading to errors sometimes going unnoticed. The objective of this study is to track the exact path the HDR source would follow in real time. The exit radiation of the HDR source was used to image a well defined matrix of markers. The images were acquired using FPD and were processed to obtain projection coordinates while an x-ray calibration image was processed to obtain marker coordinates. Each marker along with its projection represents a …

Experimental Determination Of The Stable Boundary For A Cylindrical Ion Trap, Andrew Alexander, Victor Kwong, Brad Clarke, James Benavente

Undergraduate Research Opportunities Program (UROP)

The first radio frequency (rf) quadrupole ion traps were designed with hyperbolic trapping electrodes and had the advantage of a working theoretical model with an analytical solution for the equation of motion for an ion. This came at the cost of a difficult fabrication process by the nature of the hyperbolic design. Cylindrical designs were found to be an easily constructed and functional alternative for ion trapping, but a sound theoretical model for this geometry has yet to emerge. While the hyperbolic theory yields approximate parameters for stable ion trapping, experiments conducted near the stable/unstable boundary require an experimental determination …

3d Micro-Mr And Micro-Ct Models For Determining In-Vivo Function In The Guinea Pig Knee Model Of Osteoarthritis (Oa), Kristoffer W. Dean

Undergraduate Research Opportunities Program (UROP)

Osteoarthritis (OA) is a debilitating disease that affects an estimated 27 million adults in the United States. OA causes damage to cartilage in the joints resulting in bones that rub together. This creates pain, swelling, loss of motion of the joint, and bone spurs. As the number of adults above 65 grows (an estimated 72 million people by 2030) even more people will be at high risk for OA. It is the most common type of arthritis by far yet very little is known about it including relationships between joint structure and function. In 2004, the NIH created the Osteoarthritis …

A New Receiver Placement Scheme Using Delaunay Refinement-Based Triangulation, Mohammed Rana Basheer, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a sub-optimal solution to the receiver placement and number of receiver determination problem is introduced. to achieve this overall goal, first, localization error for a received signal strength indicator (RSSI)-Based N-receiver system localizing a transmitter is estimated. Subsequently, this estimator error along with the 2D-tessellation techniques such as Delaunay refinement are used to position candidate receivers not only to minimize their number needed to meet the location error threshold but also to reduce the dilution of localization accuracy due to the layout of receivers. Rigorous mathematical analysis indicates that the receiver count generated by our Delaunay Refinement-Based …

A New Adaptive Compression Scheme For Data Aggregation In Wireless Sensor Networks, Priya Kasirajan, Carl Larsen, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless sensor nodes typically have limited processing capabilities and are powered by batteries. the amount of energy expended in transmitting a single data bit would be several orders of magnitude higher when compared to the energy needed for a 32-bit computation. Thus, to maximize network lifetime, data transmissions should be minimized without losing vital information. in this paper, a novel adaptive compression scheme using nonlinear estimation theory is proposed for data aggregation. Satisfactory performance of the proposed compression scheme in the presence of noise, distortion, and quantization errors is demonstrated using Lyapunov approach. the proposed scheme is contrasted with existing …

Experimental Investigation Of Folded Plate Girders And Slab Joints Used In Modular Construction, Kyle A. Burner

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The folded plate girder, a newly proposed bridge girder, is investigated through this thesis. The folded plate girder is cold bent out of a single sheet of steel. The cold bending eliminates the costly and inconsistent shop welds found in traditional girders. The folded plate girder is meant for application in short span bridges. The girder was subjected to an equivalent 75 year lifetime loading to investigate the fatigue performance.

The rebar detail used in the closure region between adjacent slabs has been investigated in the past by the NCHRP 12-68 project. This thesis will proposes a hooked rebar detail …

Constructability Testing Of Folded Plate Girders, Luke A. Glaser

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

A new steel girder bridge system was developed at the University of Nebraska. The innovative girder design is a box girder folded from a single steel plate that has a trapezoid shape with an opening on the bottom. The girder has application in short span bridges and accelerated construction situations. The structural performance of the girder requires investigation in all stages of a bridge’s lifecycle. This thesis contains descriptions and results from the first two tests from a series of tests developed to evaluate this new girder shape. The objective of these two tests was to investigate the constructability of …

East Bay Energy Consortium Meeting Minutes, August 2, 2010, East Bay Energy Consortium

East Bay Energy Consortium Meeting Minutes

No abstract provided.

East Bay Energy Consortium Meeting Agenda, August 2, 2010, East Bay Energy Consortium

East Bay Energy Consortium Meeting Agenda

No abstract provided.

Electrical Modelling Of Temperature Distributions In On-Chip Interconnects, Packaging, And 3d Integration, Lijun Jiang, Chuan Xu, Howard Smith, Barry Rubin, Alina Deutsch, Alain Caron

Electrical and Computer Engineering Faculty Research & Creative Works

In this talk, we will introduce a novel methodology using existing electromagnetic modelling tools for interconnect and packaging structures to simulate and model the temperature distribution without major modifications to these tools or simulated structures. This methodology can easily be integrated with the chip technology information and frame an electrical circuit simulator into an automatic, template-based simulation and optimization flow. A new accurate closed-form thermal model is further developed to simplify unnecessary object details. The model allows an equivalent medium with effective thermal conductivity (isotropic or anisotropic) to replace details in non-critical regions accurately so that complex interconnect structures can …

Analysis Of Mutual Inductance Effect Between Decoupling Capacitors On Planar Power Bus, Jingook Kim, Bruce Archambeault, James L. Knighten, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

The physics associated with mutual inductance between vias has been analyzed, and a method has been proposed to calculate the total equivalent inductance including the effect of mutual inductance. the method has been further simplified to an expression in a closed form. the equations have also been verified and shown to be accurate by measurements. © 2010 IEEE.

Improving Electromagnetic Compatibility Performance Of Packages And Sip Modules Using A Conformal Shielding Solution, Nozad Karim, Jingkun Mao, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

High-speed digital and wireless devices radiate unintentional electromagnetic noise, which can affect the normal operation of other devices within the same system, causing intra-system electromagnetic interference (EMI) problems, or contribute to the total radiated EMI from the system, resulting in potential system-level EMI issues. PCB and system level shielding may alleviate the system-level EMI between wireless PCB board and the outside environment, but seldom prevent the intra-system EMI within the shielding enclosure. Package and System in Package (SiP) level shielding is desirable to shield the unintended radiation and protect the other circuits on board. Traditionally an external metal lid is …

Metallic Nanoparticle On Micro Ring Resonator For Bio Optical Detection And Sensing, Ali Haddadpour, Yasha Yi

Publications and Research

We have numerically investigated the unique effects of metallic nanoparticle on the ring resonator, especially multiple Au nanoparticles on the micro ring resonator with the 4-port configuration on chip. For the Au nanoparticle, because it has smaller real refractive index than air and large absorption refractive index, we found that there is a blue shift for the ring resonance wavelength, instead of red shift normally observed for dielectric nanoparticles. The drop port intensity is strongly dependent on both number and size of nanoparticles, while relatively independent on position of nanoparticles. The correlation between the penetration depth of Au and the …

Supplement No. 2 To The North American Specification For The Design Of Cold-Formed Steel Structural Members, 2007 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Corrosion Dynamics Of Cobalt-Chromium Alloy F-75 Powder, Tedman Tong

Master's Theses

The increasing usage of metal-on-metal joint replacements consisting of a cobalt-chromium-molybdenum alloy requires increasing concern regarding the inevitable generation of metallic wear debris. Patients with these joint replacements exhibit elevated concentrations of cobalt and chromium ions within their serum, blood and urine. The presence of these metal ions suggests the potential for bodily damage and indicates corrosive processes are acting upon wear debris.

To understand the behavior of these corrosive processes, powders of cobalt-chromium-molybdenum alloy F-75 were studied. Four powder sizes (44, 74, 105, and 420 µm diameter) were subjected to Hank’s Balanced Salt Solution (HBSS) for a 42 day …

The Effects Of Applied Strain And Heat Treatment On The Properties Of Niti Wire During Shape Setting, Frank Zapoticla

Master's Theses

NiTi components are commonly subjected to thermo-mechanical heat treatments during production and fabrication. This study investigates the effects of applied strain of 0-10% and heat treatments of 300-600ºC for times of 2-30 minutes during shape-setting of Ti–50.8 at% Ni wire with a nominal diameter of 0.495 mm and an initial transition temperature, Af, of 12ºC. Strain was applied prior to heat treatments by coiling NiTi wire, essentially producing coiled springs, around different diameter steel mandrels to obtain different strain levels. The samples of NiTi wire under applied strain were heat treated in a salt bath, followed by a rapid quench. …

Acuta Enews August 2010, Vol 39, No. 8

ACUTA Newsletters

ln This lssue

From the President........ Matt Arthur, Washington Univ. in St. Louis, ACUTA President

Web Seminar: The Future of United Communications

PAETEC Provides Calling Service

Tech Talk: Thinking Holistically about Mobility........ Kevin Tanzillo, Dux PR

Add Names from Your Campus to Your ACUTA Roster

Learn More about UC, WiFi, FMC, Green IT and More from Your Desktop

FYI: Useful Information from the Campus........... Student Monitor

Designing a DAS.............. Ron Walczak, Walczak Technology Consultants

Visit the ACUTA Community Often!

Board Report............... George Denbow, Univ. of Texas, ACUTA Secretary/ Treasurer

Info Links................... Randy Hayes, Univ. of Northern Iowa

Washington Update Newsletter …

Cantor's Paradise Regained: Constructive Mathematics From Brouwer To Kolmogorov To Gelfond, Vladik Kreinovich

Departmental Technical Reports (CS)

Constructive mathematics, mathematics in which the existence of an object means that that we can actually construct this object, started as a heavily restricted version of mathematics, a version in which many commonly used mathematical techniques (like the Law of Excluded Middle) were forbidden to maintain constructivity. Eventually, it turned out that not only constructive mathematics is not a weakened version of the classical one -- as it was originally perceived -- but that, vice versa, classical mathematics can be viewed as a particular (thus, weaker) case of the constructive one. Crucial results in this direction were obtained by M. …

Constraint-Related Reinterpretation Of Fundamental Physical Equations Can Serve As A Built-In Regularization, Vladik Kreinovich, Juan Ferret, Martine Ceberio

Departmental Technical Reports (CS)

Many traditional physical problems are known to be ill-defined: a tiny change in the initial condition can lead to drastic changes in the resulting solutions. To solve this problem, practitioners regularize these problem, i.e., impose explicit constraints on possible solutions (e.g., constraints on the squares of gradients). Applying the Lagrange multiplier techniques to the corresponding constrained optimization problems is equivalent to adding terms proportional to squares of gradients to the corresponding optimized functionals. It turns out that many optimized functionals of fundamental physics already have such squares-of-gradients terms. We therefore propose to re-interpret these equations -- by claiming that they …

Performance Measures In Acousto-Optic Chaotic Signal Encryption System Subject To Parametric Variations And Additive Noise, Monish Ranjan Chatterjee, Anjan K. Ghosh, Mohammed A. Al-Saedi

Electrical and Computer Engineering Faculty Publications

Signal encryption and recovery using chaotic optical waves has been a subject of active research in the past 10 years. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption using a low-amplitude sinusoidal signal applied via the bias input of the sound cell driver.

Subsequent recovery of the message signal was carried out via a heterodyne strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell. The simulation results, though encouraging, were limited to relatively …

Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Electromagnetic (EM) propagation velocities play an important role in the determination of power and energy flow in materials and interfaces. It is well known that group and phase velocities need to be in opposition in order to achieve negative refractive index.

Recently, we have shown that considerable differences may exist in phase, group and signal/energy velocities for normal and anomalous dispersion, especially near dielectric resonances. This paper examines the phase and group velocities in the presence of normal and anomalous dispersion, and group velocity dispersion (GVD), which requires introduction of the second order coefficient in the permittivity and permeability models.