Engineering Commons^™

Layered Unequal Loss Protection For Progressive Image Transmission Over Packet Loss Channels, Jianfei Cai, Xiangjun Li, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

In the past, many schemes have been proposed for progressive image transmission using unequal error protection (UEP) or unequal loss protection (ULP). However, most existing UEP/ULP schemes do not consider the minimum image quality requirement and usually have high computation complexity. In this paper, we propose a layered ULP (L-ULP) scheme for progressive image transmission over packet loss channels, which is able to solve the mentioned problems of existing ULP schemes by smartly choosing the layers. The numerical results show that the proposed L-ULP scheme is quite promising for fast image transmission over packet loss networks.

Florida's Energy Future: Opportunities For Our Economy, Environment And Security - Executive Summary, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

The future of Florida's economy, environment and security is inextricably intertwined with our energy use decisions. Our state has one of the nation's fastest growing populations, promoting rapid expansion of an energy industry that imports its fuel supplies. Florida exports approximately $32 billion per year for these energy fuels. Moreover, the Florida economy depends critically on tourism and agriculture, and the fuels and energy products that maintain them. Our pristine environment is the primary natural resource supporting this unique economic engine and the adverse effects of our rapidly growing energy use now stress it. Our State's economic well-being and security …

Florida's Energy Future: Opportunities For Our Economy, Environment And Security - Appendices, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

The future of Florida's economy, environment and security is inextricably intertwined with our energy use decisions. Our state has one of the nation's fastest growing populations, promoting rapid expansion of an energy industry that imports its fuel supplies. Florida exports approximately $32 billion per year for these energy fuels. Moreover, the Florida economy depends critically on tourism and agriculture, and the fuels and energy products that maintain them. Our pristine environment is the primary natural resource supporting this unique economic engine and the adverse effects of our rapidly growing energy use now stress it. Our State's economic well-being and security …

Florida's Energy Future: Opportunities For Our Economy, Environment And Security, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

The future of Florida's economy, environment and security is inextricably intertwined with our energy use decisions. Our state has one of the nation's fastest growing populations, promoting rapid expansion of an energy industry that imports its fuel supplies. Florida exports approximately $32 billion per year for these energy fuels. Moreover, the Florida economy depends critically on tourism and agriculture, and the fuels and energy products that maintain them. Our pristine environment is the primary natural resource supporting this unique economic engine and the adverse effects of our rapidly growing energy use now stress it. Our State's economic well-being and security …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Iii Second Quarterly Report, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells are the most appropriate shape for superconducting cavities. The need for very clean surfaces lead to the use of a buffered chemical polishing produce for surface cleaning to get good performance of the cavities. The third phase concludes the experimental a fluid flow study and optimization study. The first quarter and second quarter of phase three also begins the experimental set-up of secondary emission studies from niobium in superconducting mode. This …

Optically Coupled Etalons And Methods Of Making And Using Same, Michael A. Scobey, Lucien P. Ghislain, Dennis Derickson, Loren F. Stokes

Electrical Engineering

Optical elements comprise stacked, optically matched and optically coupled etalons, at least one of the optically coupled etalons comprising first and second selectively transparent thin film mirror coatings on opposite surfaces of a bulk optic. The bulk optic defines the cavity spacing of the etalon and may, for example be formed of a monolithic body of silica or other optically transparent glass diced from a glass wafer. The bulk optic may further comprise a wedge coating of progressively increasing thickness overlying the monolithic glass body and compensating for, or offsetting non-parallelism of the bulk optic. The bulk optic may further …

Bar Clamp Having Ergonomic Handle, M. Susan Hallbeck, Myung-Chul Jung

Department of Mechanical and Materials Engineering: Faculty Publications

The present invention generally relates to a handle assembly for a hand operable bar clamp having a fixed jaw, a movable jaw and a drive for translating the movable jaw towards the fixed jaw. The assembly includes a handgrip and a trigger handle. The handgrip having an elongated rear portion has a generally rounded surface and being contoured to complement the natural transverse curve pf a human palm. The trigger handle is pivotal with respect to the handgrip. The trigger handle included an elongated front portion having a rounded front surface and being contoured to complement the natural palmer curve …

Transcriptome-Based Determination Of Multiple Transcription Regulator Activities In Escherichia Coli By Using Network Component Analysis, Katy Kao, Young-Lyeol Yang, Riccardo Boscolo, Chiara Sabatti, Vwani Roychowdhury, James Liao

Faculty Publications

Cells adjust gene expression profiles in response to environmental and physiological changes through a series of signal transduction pathways. Upon activation or deactivation, the terminal regulators bind to or dissociate from DNA, respectively, and modulate transcriptional activities on particular promoters. Traditionally, individual reporter genes have been used to detect the activity of the transcription factors. This approach works well for simple, non-overlapping transcription pathways. For complex transcriptional networks, more sophisticated tools are required to deconvolute the contribution of each regulator. Here, we demonstrate the utility of network component analysis in determining multiple transcription factor activities based on transcriptome profiles and …

Hands-On Fun & Games In Space Also, On Land, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Hands-On Fun & Games in Space Also, on Land" from January 12, 2004.

Global Shear Wave Velocity Database For Probabilistic Assessment Of The Initiation Of Seismic-Soil Liquefaction, Robert Kayen, Raymond B. Seed, Robb E.S. Moss, Onder K. Cetin, Y. Tanaka, Kohji Tokimatsu

Civil and Environmental Engineering

Engineering practitioners commonly use penetration-based methods (SPT & CPT) for assessment of seismic liquefaction triggering hazard. On the horizon, shear wave velocity (V_s) may offer engineers a third tool that is lower cost and provides more physically meaningful measurements. Development of the shear wave velocity liquefaction method has been hampered by a paucity of published velocity profiles; particularly in deeper soil deposits (>10m) and deposits subjected to high cyclic stress ratios (CSR > 0.3). A review of the literature reveals that most historic liquefaction sites fitting this depth and CSR criteria are located in Asia, though most of …

Process For The Physical Segregation Of Minerals, Jon C. Yingling, Rajive Ganguli

Manufacturing Systems Engineering Faculty Patents

With highly heterogeneous groups or streams of minerals, physical segregation using online quality measurements is an economically important first stage of the mineral beneficiation process. Segregation enables high quality fractions of the stream to bypass processing, such as cleaning operations, thereby reducing the associated costs and avoiding the yield losses inherent in any downstream separation process. The present invention includes various methods for reliably segregating a mineral stream into at least one fraction meeting desired quality specifications while at the same time maximizing yield of that fraction.

Snow Groomer Assembly, Philip J. Quenzi, Russell G. Alger

Michigan Tech Patents

A snow groomer includes a movable platform, a prime mover mounted to the platform and a grooming drum rotatably driven by the prime mover for rotation in a direction opposite the traveling direction of the snow groomer. The grooming drum includes axially spaced apart and radially protruding ribs that extend circumferentially around the drum. The ribs include circumferentially spaced apart apertures and the apertures of each rib are aligned with the apertures of the other ribs. Elongated cutting teeth extend through the apertures of the ribs and have a cross-sectional area that is smaller than the apertures such that the …

Experimental Investigation Of Statistical Moments Of Travel Time In Grid-Generated Turbulence, Tatiana A. Andreeva, S. B. Meleshi, William W. Durgin

Office of the Provost Scholarship

An experimental technique for investigation of the behavior of acoustic wave propagation through a turbulent medium is discussed. The present study utilizes the ultrasonic travel-time technique to diagnose a grid-generated turbulence. The statistics of the travel-time variations of ultrasonic wave propagation along a path are used to determine some metrics of the turbulence. Experimental data obtained using ultrasonic technique confirms numerical and theoretical predictions of nonlinear increase of the first-order travel time variance with propagation distance.

Some Systemic Issues In The Development Of The Aerospace Industry Technical Workforce Of The Future, John H. Mcmasters, Russell M. Cummings

Aerospace Engineering

This paper is a continuation of the authors’ previous examinations of a suite of issues surrounding the putative decline in aeronautics in this country. The purpose of this paper is to discuss three specific issues believed to be of particular importance to the future of our industry. The first is the question of how many engineers we may need in our future as we confront the problem of an aging workforce and the globalization of our industry. The second is the question of what skills and abilities these engineers will need to possess as the overall industry continues to evolve. …

Detached-Eddy Simulation Of Slat And Flap Aerodynamics For A High-Lift Wing, Russell M. Cummings, Scott A. Morton, James R. Forsythe

Aerospace Engineering

Three-dimensional multi-element wings are simulated to investigate slat and flap aerodynamics using Detached-Eddy Simulation. The computations are performed by solving the Navier-Stokes equations on unstructured grids. All of the computed cases include the main wing with a half-span flap deflected to 39 degrees and a three-quarter-span slat deflected to 6 degrees. Computations of the model, which simulates a landing configuration at 10 degrees angle of attack and a chord-based Reynolds number of 3.7 million, are validated with surface pressure measurements acquired at the NASA Ames 7- by 10-Foot Wind Tunnel. The results increase the computational knowledge of how to accurately …

Airplane Design And The Biomechanics Of Flight – A More Completely Multi- Disciplinary Perspective, John H. Mcmasters, Russell M. Cummings

Aerospace Engineering

Aeronautics is usually presumed to have started as a formal engineering discipline somewhere in historical time between the mythological experiments of Daedalus and his ill-fated son, Icarus; and the dreams and schemes of Leonardo da Vinci during the Italian Renaissance. As reviewed in this paper, “aeronautics” has a far longer history, extending over a period of about 300 million years beginning with the evolution of the ability of insects to fly. With the advent of the success of the Wright brothers, technologists quickly turned their attention from the inspirations and lessons provided by natural models of flying machines to …

An Embedded Boundary Cartesian Grid Scheme For Viscous Flows Using A New Viscous Wall Boundary Condition Treatment, David D. Marshall, Stephen M. Ruffin

Aerospace Engineering

This work presents a new viscous wall boundary condition technique for embedded Cartesian grid schemes in order to model laminar viscous flows. The development of viscous effects modeling using pure Cartesian grids with cut cells at the surface has been hampered by the widely varying control volume sizes associated with the mesh refinement and the cut cells associated with the solid surface. This scheme removes the cells adjacent to the surface from the control volume formulation. These cells are instead solved via an interpolation technique which utilizes the wall boundary conditions to build the interpolating functions. Two different interpolation techniques …

A New Inviscid Wall Boundary Condition Treatment For Embedded Boundary Cartesian Grid Schemes, David D. Marshall, Stephen M. Ruffin

Aerospace Engineering

This work presents a new inviscid wall boundary condition technique for embedded Cartesian grid schemes. This scheme eliminates the time step restrictions associated with the arbitrarily small control volumes that can result when the surface cuts the Cartesian control volumes. The cells adjacent to the surface are removed from the control volume formulation and are instead solved via an interpolation technique which utilizes the wall boundary conditions to build the interpolating functions. Two different interpolation techniques are presented, one without considering wall curvature and one considering wall curvature. Results are compared to a two-dimensional airfoil case and a three-dimensional wing …

Total Reduced Sulfur Concentrations In The Vicinity Of Beef Cattle Feedlots, Richard K. Koelsch, Bryan L. Woodbury, David E. Stenberg, Daniel N. Miller, Dennis D. Schulte

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A field survey of total reduced sulfur (TRS) concentrations in the vicinity of beef cattle feedlots was conducted to compare field observations against current regulatory thresholds. In addition, environmental factors that may contribute to increased TRS emissions were evaluated. It was observed that TRS levels in the vicinity of beef cattle feedlots are not likely to exceed current regulatory thresholds used by midwestern states. It was further noted that concentration of TRS varies with air temperature and time of day. However, wet feedlot surface conditions and wind speed had almost no impact upon observed concentrations.

Microscale Polymeric Helical Structures Produced By Electrospinning, Royal Kessick, Gary C. Tepper

Mechanical and Nuclear Engineering Publications

Microscale helical coils consisting of a composite of one conducting and one nonconducting polymer were produced using electrospinning. The nonconducting polymer was poly(ethylene oxide) and the conducting polymer was poly(aniline sulfonic acid). The coil structures were studied over a range of processing conditions and fiber composition. The data suggest that the helical structures are formed due to viscoelastic contraction upon partial neutralization of the charged fibers. Polymeric microcoils may find applications in microelectromechanical systems, advanced optical components, and drug delivery systems.

Benchmarking Of Flexibility And Needs - 2004, Charles Burt, Dan Howes, Franklin Gaudi, Monica Holman

BioResource and Agricultural Engineering

ITRC interviewed irrigation district personnel from 25 agricultural districts in eastern Washington, northern Idaho and western Montana.

Data were analyzed to determine the degree of water delivery flexibility provided to farmers and the extent of existing and planned district modernization. This is the fourth such report the Irrigation Training and Research Center (ITRC) has published for irrigation districts in the western US. The first two evaluations were conducted on behalf of the Mid-Pacific Region of the US Bureau of Reclamation (USBR) and included California irrigation districts that had long-term federal contracts. The third report was prepared on behalf of the …

Interfaces, Volume 7, Issue 1 - Winter 2004

INTERFACES: Newsletter of the Nebraska Center for Materials and Nanoscience

Facility Focus (I): Multipurpose X-Ray System Zeng Named Guggenheim Fellow Sigma Xi Honors to CMRA Faculty, Staff and Students Best Paper Awards Degree of Doctor Honoris Causa Recent Patents Facility Focus(II): Equipment Upgrade in Electron Microscopy CMRA Welcomes Fereydoon Namavar Research Spotlight: Stephen Ducharme Spinning Continuous Fibers for Nanotechnology

Potential Effects Of Long-Lead Hydrologic Predictability On Missouri River Main-Stem Reservoirs, Edwin P. Maurer, Dennis P. Lettenmaier

Civil, Environmental and Sustainable Engineering

Understanding the links between remote conditions, such as tropical sea surface temperatures, and regional climate has the potential to improve streamflow predictions, with associated economic benefits for reservoir operation. Better definition of land surface moisture states (soil moisture and snow water storage) at the beginning of the forecast period provides an additional source of streamflow predictability. The value of long-lead predictive skill added by climate forecast information and land surface moisture states in the Missouri River basin is examined. Forecasted flows were generated that represent predictability achievable through knowledge of climate, snow, and soil moisture states. For the current main-stem …

Mapping Surface Polarization In Thin Films Of The Ferroelectric Polymer P(Vdf-Trfe)., Bradley W. Peterson, Stephen Ducharme, Vladimir M. Fridkin, Timothy J. Reece

Stephen Ducharme Publications

Pyroelectric Scanning Microscopy (PSM) has been developed to enable mapping of surface polarization in ferroelectric thin films, in particular the copolymer polyvinylidene fluoride trifluororethylene, or P(VDF-TrFE). The Chynoweth method for dynamically measuring pyroelectric current is employed in conjunction with a micropositioning system to construct two-dimensional images of the film polarization. These images have revealed enhancement of the polarization near the edges of the film below the average coercive field, with the center's polarization increasing thereafter to meet the edge value at saturation.

The Effect Of Loading On Disturbance Sounds Of The Atlantic Croaker Micropogonius Undulatus: Air Versus Water, Michael L. Fine, Justin Schrinel, Timothy M. Cameron

Biology Publications

Physiological work on fish sound production may require exposure of the swimbladder to air, which will change its loading (radiation mass and resistance) and could affect parameters of emitted sounds. This issue was examined in Atlantic croaker Micropogonius chromis by recording sounds from the same individuals in air and water. Although sonograms appear relatively similar in both cases, pulse duration is longer because of decreased damping, and sharpness of tuning (Q factor) is higher in water. However, pulse repetition rate and dominant frequency are unaffected. With appropriate caution it is suggested that sounds recorded in air can provide a useful …

Determination Of The Carrier Concentration In Ingaasn∕Gaas Single Quantum Wells Using Raman Scattering, Patrick A. Grandt, Aureus E. Griffith, M. O. Manasreh, D. J. Friedman, S. Doğan, D. Johnstone

Electrical and Computer Engineering Publications

Raman scattering from longitudinal optical phonon-plasmon coupled mode was observed in a series of InGaAsN∕GaAs single quantum well samples grown by metalorganic vapor phase epitaxy. The phonon-plasmon mode spectra were fitted with the dielectric constant function based on Drude model that contains contributions from both lattice vibrations and conduction electrons. The carrier concentration is calculated directly from the plasmon frequency, which is obtained from the fitting procedure. An empirical expression for the electron concentration, [n], in InGaAsN∕GaAs samples is determined as [n]≈{2.35×1016(ωm−502)}cm−3, where ωm is the peak of the upper frequency branch, L+, of the phonon-plasmon mode measured in unit …

Alternate Spintronic Analog Of The Electro-Optic Modulator, S. Bandyopadhyay, M. Cahay

Electrical and Computer Engineering Publications

There is significant current interest in spintronic devices fashioned after a spin analog of the electro-opticmodulator proposed by Datta and Das [Appl. Phys. Lett.56, 665 (1990)]. In their modulator, the “modulation” of the spin-polarized current is carried out by tuning the Rashba spin-orbit interaction with a gate voltage. Here, we propose an analogous modulator where the modulation is carried out by tuning the Dresselhaus spin-orbit interaction instead, using a split gate. Additionally, the magnetization of the source and drain contacts in our device is transverseto the channel, whereas in the Datta-Dasdevice, it is along the channel. Therefore, in the …

Thermal Stability Of Electron Traps In Gan Grown By Metalorganic Chemical Vapor Deposition, D. Johnstone, S. Doğan, J. Leach, Y.-T. Moon, Y. Fu, Y. Hu, Hadis Morkoç

Electrical and Computer Engineering Publications

Deep level transient spectroscopy was used to investigate the thermal stability of electron traps in n-type GaN grown by metalorganic chemical vapor deposition. The concentration of traps at 160 and at 500K increased more than fivefold over the course of several 700Kanneal cycles, while a peak at 320K increased by a factor of only 1.19. The increase in the trap concentration with repeated annealing might be due to a mobile trap or loss of passivant. Hydrogen is very likely present in high concentration in the epilayer, and its passivating effects may be lost with annealing.

Studies Of Ingan∕Gan Multiquantum-Well Green-Light-Emitting Diodes Grown By Metalorganic Chemical Vapor Deposition, K. S. Ramaiah, Y. K. Su, S. J. Chang, C. H. Chen, F. S. Juang, H. P. Liu, I. G. Chen

Electrical and Computer Engineering Publications

InGaN(3nm)∕GaN(5nm) three period multiquantum green-light-emitting diodes(LEDs) grown by the metalorganic chemical vapor deposition technique have been studied using high-resolution transmission electron microscopy (HRTEM), double crystal high resolution x-ray diffraction (HRXRD) and low temperature photoluminescence. HRTEM analysis showed that the defect density gradually decreased in the growth direction with increasing thickness. Self-assembled quantum dot-likestructures in the wells and black lumps between the well and barrier due to In segregation and strain contrast were observed, respectively. The HRXRD spectrum of the green LEDstructure was simulated using the kinematical theory method to obtain the composition and thickness of the well and barrier. The …

Reexamination Of Some Spintronic Field-Effect Device Concepts, S. Bandyopadhyay, M. Cahay

Electrical and Computer Engineering Publications

Current interest in spintronics is largely motivated by a belief that spin-based devices (e.g., spin field-effect transistors) will be faster and consume less power than their electronic counterparts. Here we show that this is generally untrue. Unless materials with extremely strong spin-orbit interaction can be developed, the spintronic devices will not measure up to their electronic cousins. We also show that some recently proposed modifications of the original spin field-effect transistor concept of Datta and Das [Appl. Phys. Lett.56, 665 (1990)] actually lead to worse performance than the original construct.