Engineering Commons^™

System For Sequentially Providing Aberation Corrected Electromagnetic Radation To A Spot On A Sample At Multiple Angles Of Incidence, Martin M. Liphardt, John A. Woollam,

Department of Electrical and Computer Engineering: Faculty Publications

A system for sequentially providing electromagnetic radia tion to a spot on a sample at different angles of incidence, and after reflection therefrom into a detector. The system includes a plurality of spherical mirrors, and a refractive element for correcting aberration.

Rotating Or Rotatable Compensator Systemi Providing Aberation Corrected Electromagnetic Raadation To A Spot On A Sample At Multiple Angles Of Ancidence, Martin M. Liphardt, Blaine D. Johs, Jeffrey S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

The present invention relates to ellipsometer systems, and more particularly to ellipsometer systems comprising trans missive rotating or stepwise rotatable compensators for continuously or step-wise varying polarization states and further comprising transmissive multi-element lens focusing of a spectroscopic electromagnetic beam into a small, chromatically relatively undispersed area spot on a sample system. The ellipsometer system optionally is present in an environmental control chamber.

Buffer Law And Transitional Roughness Effect In Turbulent Open-Channel Flows, Junke Guo, Pierre Y. Julien

Department of Civil and Environmental Engineering: Faculty Publications

A novel and complete velocity profile law is presented for turbulent open channel flows. The law embeds the linear law in the viscous sublayer; the quartic law due to turbulent bursting that must satisfy instantaneous mass conservation, the modified log-wake law in the outer region and the effects of wall roughness. Specifically, an arctangent law smoothly connects the linear law with the log law of the wall. Combining the arctangent law with the modified log-wake law, a continuous velocity profile is proposed for smooth boundary conditions. A complete velocity profile is obtained after subtracting a new roughness function. Finally, the …

Creating Micro- And Nanostructures On Tubular And Spherical Surfaces, O. Lima, L. Tan, A. Goel, Lmehrdad Negahban, Z. Li

Nebraska Center for Materials and Nanoscience: Faculty Publications

The authors developed a new technique to create micro- and nanometer scale structures on curved free-standing objects by combining embossing/imprinting lithography approaches with mechanical loadings on elastic films. Embossing/imprinting generates small structures and mechanical loading determines shape or geometry of the final object. As a result, a portion of the tubes with a radius between 0.5 and 3.5 mm and a portion of the spheres with a radius between 2.4 and 7.0 mm were fabricated with grating line features (period of 700 nm) and microlens array features (lens radius of 2.5 µm) atop, respectively. It was found that both static …

Department Of Biological Systems Engineering Newsletter, Issue 3, Vol. 2, December 2007

BSE Department Magazine

Contents:
New Tractor Test Track Dedication
From the Department Head
Awards
Meet the Faculty
Alumni News
Student News
Summer Graduations
Quarter-scale Tractor Competition
ASABE Student Branch
ASABE International Preprofessional Council
Distinguished Fellowship Awards
John and Louise Skala Fellowships
Researching Plant Sterols
Milton E. Mohr Fellowship in Agriculture
Scholarships and Ice Cream
100 YEARS As a University of Nebraska Department
Alumnus Profile
Career opportunities in food engineering
Congratulations
Comings and Goings

Acuta Enews December 2007, Vol.36, No. 12

ACUTA Newsletters

ln This lssue

From the President............. Walt Magnussen, Texas A&M Univ., ACUTA President

Check lt Out: RFls/RFPs, Job Postings, Press Releases

Tech Talk: Mash Up Your Data and Serve lt with Gravy................ Kevin Tanzillo, Dux PR

Board Report.................... Riny Ledgerwood, Son Diego State Univ., ACUTA, Sec../Treasurer

DC Update............ Jeanne Jansenius, Sewanee, The University of the South

lnfo Links............... Randy Hayes, Univ, of Northern lowa

Why Do We Do What We Do?...................... Bill Farris, Univ. of Kansas

FYI: Useful Information from Campus............. Eric Weil, Student Monitor

Nominations Open for Institutional Excellence Awards............... Carmine Piscopo, Providence College

Thanks to 2007 Sponsors

PAETEC …

Optimal Receiver For Space Time Spreading Across A Time Hopping Ppm Over Ultra Wideband Saleh-Valenzuela Mimo Channel, Peter Vial, Beata J. Wysocki, Tadeusz A. Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

This paper outlines a technique which can use multiple transmit antennas to send more than one binary bit using the same number of transmit antennas over a single transmission. It uses Ultra Wideband orthogonal pulse position modulation to achieve this, with the receiver employing a Rake receiver and a Maximum Ratio Combiner optimal detector. This is done over a Space Time Spreading Time Hopping Ultra Wideband Pulse Position Modulation system assuming a rich multipath Saleh-Valenzuela MIMO channel model. Simulation results indicate that a significant gain can be achieved compared with other proposed schemes utilising multiple transmit antennas for Ultra Wide …

Scalability Of Manet Routing Protocols For Heterogeneous And Homogenous Networks, Huda Al Amri, Mehran Abolhasan, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

In Mobile Ad hoc Network (MANET), mobility, traffic and node density are main network conditions that significantly affect the performance of routing protocols. Much of the previous researches in MANET routing have focused on developing strategies, which suit one specific networking scenario. Therefore, there is no existing protocol that can work well in all different networking scenarios. This paper reviews characteristics of each different classes of routing protocols. Moreover, most of current routing protocols assume homogeneous networking conditions where all nodes have the same capabilities and resources. Although homogenous networks are easy to model and analysis, they exhibits poor scalability …

Closed-Form Derivations Of Isi And Mui For Time-Reversed Ultra Wideband, K. Popovski, Beata J. Wysocki, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Through transmitter pre-filtering, a time reversed UWB system is capable if harnessing a multipath channel to achieve temporal and spatial focusing. Unfortunately, large RMS channel delay spread leads to significant intersymbol and multiuser interference. This paper presents closed-form expressions for self and multi-user interference for a UWB system utilizing a time-reversed approach. The influence of user multiplexing codes is taken to account through incorporation of a ‘separation probability’, which characterizes a family of hopping sequences. The standardized IEEE 802.15.3a channel model is applied, and the derived performances are compared with that of a simulated time hopped time-reversed UWB system.

The Tri-Frame Model, Elsje Pienaar, Hendrik J. Viljoen

Hendrik J. Viljoen Publications

The tri-frame model gives mathematical expression to the transcription and translation processes, and considers all three reading frames. RNA polymerases transcribe DNA in single nucleotide increments, but ribosomes translate mRNA in pairings of three (triplets or codons). The set of triplets in the mRNA, starting with the initiation codon (usually AUG) defines the open reading frame (ORF). Since ribosomes do not always translocate three nucleotide positions, two additional reading frames are accessible. The -1RF and the +1RF are triplet pairings of the mRNA which are accessed by shifting one nucleotide position in the 5’ and 3’ directions respectively. Transcription is …

Modelagem Da Vida De Fadiga E Do Acúmulo De Deformações Permanentes Em Pavimentos Asfálticos Por Meio De Um Modelo De Dano Contínuo, Victor Ferreira Teixeira, Flavio V. Souza, Jorge Barbosa Soares

Department of Mechanical and Materials Engineering: Faculty Publications

: It is known that the conditions of the Brazilian roadways have an enormous impact over the national economy. In face of this problem, there is a need for new methodologies for pavement analyses and design that can more accurately predict pavement distresses. Among the main methods currently used, one can find purely empirical methods and mechanistic-empirical methods which make use of the pavement structure response. The evolution of numerical methods such as the Finite Element Method (FEM) or the Boundary Element Method (BEM) has made the mechanistic-empirical methods more popular for pavement analysis applications. This work shows a mechanistic …

Response Of Phlebotomine Sand Flies To Light-Emitting Diode-Modified Light Traps In Southern Egypt, D. F. Hoel, Emad Y. Fawaz, J.E Butler, N. Watany, S. S. El-Hossary, J. Villinski

U.S. Navy Research

Centers For Disease Control and Prevention (CDC) light traps were modified for use with light-emitting diodes (LED) and compared against a control trap (incandescent light) to determine the effectiveness of blue, green, and red lights against standard incandescent light routinely used for sand fly surveillance. Light traps were baited with dry ice and rotated through a 4 x 4 Latin square design during May, June, and July, 2006. Trapping over 12 trap nights yielded a total of 2,298 sand flies in the village of Bahrif, 6 km north of Aswan on the east bank of the Nile River in southern …

Development Of A Tl-5 Vertical Faced Concrete Median Barrier Incorporating Head Ejection Criteria, Scott Rosenbaugh, Dean L. Sicking, Ronald K. Faller

Nebraska Department of Transportation: Research Reports

No abstract provided.

Phase Iii Development Of A Short-Radius Guardrail For Intersecting Roadways, Cody S. Stolle, Karla A. Polivka, Robert W. Bielenberg, Ronald K. Faller, Dean L. Sicking, John R. Rohde, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Application Of Intermediate Wavelength Band Spectroscopic Ellipsometry To In-Stu. Real Time Fabrication Of Multiple Layer Alternating Hghalow Refractive Index Filters, Blaine D. Johs, Jeffery S. Hale, John A. Woollam, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is application of oblique angle of incidence, reflection and/or transmission mode spectroscopic ellipsometry PSI and/or DELTA, (including combinations thereof and/or mathematical equivalents), vs. wavelength data over an intermediate wavelength band range around a pass or reject band, to monitor and/or control fabrication of multiple layer high/low refractive index band-pass, band-reject and varied attenuation vs. wavelength thin film interference filters, either alone or in combination with transmissive non-ellipsometric electromagnetic beam turning point vs. layer data obtained at an essentially normal angle of incidence.

A Theoretical Framework For Quality-Aware Cross-Layer Optimized Wireless Multimedia Communications, Song Chi, Haohong Wang, Dalei Wu

Department of Electrical and Computer Engineering: Faculty Publications

Although cross-layer has been thought as one of themost effective and efficient ways formultimedia communications over wireless networks and a plethora of research has been done in this area, there is still lacking of a rigorous mathematical model to gain indepth understanding of cross-layer design tradeoffs, spanning from application layer to physical layer. As a result, many existing cross-layer designs enhance the performance of certain layers at the price of either introducing side effects to the overall system performance or violating the syntax and semantics of the layered network architecture. Therefore, lacking of a rigorous theoretical study makes existing cross-layer …

Effects Of Climate Change On Aquatic Invasive Species And Implications For Management And Research (Powerpoint Presentation), Britta Bierwagen, Roxanne Thomas, Kathryn Mengerink, Austin Kane

United States Environmental Protection Agency: Staff Publications

Contents:
Five Key Lessons from Report
Climate Change Effects on Aquatic Ecosystems
Climate Change Effects on Aquatic Invasive Species may…
Other stressors may…
Why focus on AIS?
This Report Includes
Report Process
Climate Change & Invasion Pathway
Climate Change & Interacting Stressors
AIS Management Activities
State Managers’ Reported Concerns
Capacity to Adapt to Climate Change
Accounting for Changing Conditions
Information & Research Needs
Research Recommendations
Possible Next Steps
On-going Activities

Acuta Enews November 2007, Vol.36, No. 11

ACUTA Newsletters

In This Issue

From ACUTA Headquarters.................. Jeri A. Semer, CAE, ACUTA Executive Director

Tech Talk: There Are Lots of Zeroes Behind a Yottabit............ Kevin Tanzillo, Dux PR.

DC Update............... Jeanne Jansenius, Sewanee, The University of the South

lnfo Links ............... Randy Hayes, Univ. of Northern lowa

Board Report............... Riny Ledgerwood, San Diego State Univ., ACUTA Sec./Treasurer

ls Your lP Phone Counterfeit?..................... Gary Audin, Delphi

FYI: Useful lnformation from Campus.................. Eric Weil, Student Monitor

Thanks to 2007 Exhibitors

Welcome New Members

Check lt Out: RFls/RFPs, Job Postings, Press Releases

Manure Testing: What To Request?, Charles A. Shapiro, Charles S. Wortmann

Biological Systems Engineering: Papers and Publications

Manure testing is necessary to make optimum use of manure while protecting water resources. This publication is a guide to providing information on a Manure Sample Sub­mission Form for reliable interpretation of results.

The tests most frequently needed to optimize nutrient management are total and ammonium nitrogen (NH₄-N), phosphorus (P₂O₅), potassium (K₂O), pH, soluble salts, sodium, and dry matter content.

Nitrogen. Manure contains both organic and inorganic forms of nitrogen. Ammonium-N is the primary inorganic form in manure and is readily available to crops. Nitrate-N concentration is usually too small to …

Midwest Guardrail System For Long-Span Culvert Application, Robert W. Bielenberg, Ronald K. Faller, John R. Rohde, Dean L. Sicking, James C. Holloway, Karla A. Polivka, John D. Reid, Erin M. Allison

Nebraska Department of Transportation: Research Reports

No abstract provided.

Transfected Cell Arrays For The High-Throughput Analysis Of Transcription Factor Activity, Abigail D. Bellis, Angela K. Pannier, Lonnie D Shea

Department of Biological Systems Engineering: Conference Presentations and White Papers

Transfected cell arrays offer a high-throughput method that allows for the parallel analysis of multiple pathways or genes within a physiological context. We have developed a transfected cell array that employs a dual-plasmid system that gives the ability to normalize for spot-to-spot variation in transfection efficiency. Each spot within the array contains a constitutively active normalization plasmid encoding for renilla luciferase as well as a functional plasmid that contains transcription factor specific binding elements driving the expression of firefly luciferase. Dual bioluminescent imaging provides highly sensitive analysis while limiting post-transfectional processing. Adequate transfection poses a significant challenge in extending this …

Development Of The Midwest Guardrail System (Mgs) W-Beam To Thrie Beam Transition Element, Ronald K. Faller, John R. Rohde, Robert W. Bielenberg, Karla A. Polivka, Dean L. Sicking, John D. Reid, Craig M. Eller, Erin M. Allison

Nebraska Department of Transportation: Research Reports

No abstract provided.

Linear Tactile Nanodevice With Resolution On Par With Human Finger, Ravi F. Saraf, Vivek C. Maheshwari, Chieu Nguyen

Ravi Saraf Publications

A large area thin-film nanodevice made by self-assembly containing electroluminescent nanoparticles is reported. The ~100 nm thick device on application of potential across the top and bottom surface of the film converts local pressure to light. The intensity of the electroluminescent light is linearly proportional to the applied local compressive stress. By imaging the light, the stress distribution over the area of contact is obtained at resolution on par with human finger.

Effect Of Tip Resonances On Tunnelling Anisotropic Magnetoresistance In Ferromagnetic Break Junctions: A First-Principles Study, John D. Burton, Renat F. Sabirianov, Julian P. Velev, O. N. Mryasov, Evgeny Y. Tsymbal

Materials Research Science and Engineering Center: Faculty Publications

First-principles calculations of electron tunneling transport in nanoscale Ni and Co break-junctions reveal strong dependence of the conductance on the magnetization direction, an effect known as tunneling anisotropic magnetoresistance TAMR. An important aspect of this phenomenon stems from resonant states localized in the electrodes near the junction break. The energy and broadening of these states is strongly affected by the magnetization orientation due to spin-orbit coupling, causing TAMR to be sensitive to bias voltage on a scale of a few millivolts. Our results bear a resemblance to recent experimental data and suggest that TAMR driven by resonant states is a …

Use Of Ellipsometry And Surface Plasmon Resonance In Monitoring Thin Film Deposition Or Removal From A Substrate Surface, John A. Woollam, Blaine D. Johs, Thomas E. Tiwald, Martin M. Liphardt, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

Improved methodology for monitoring deposition or removal of material to or from a process and/or Wittness substrate Which demonstrates a negative e1 at some Wave length. The method involves detection of changes in P-polarized electromagnetism ellipsometric DELTA at SPR Resonance Angle-of-lncidence (A01) to monitor deposition of and/or removal of minute amounts of materials onto, or from, said process and/or Witness substrate. The methodology can optionally monitor ellipsometric PS1, and involves simultaneously or sequentially applying non-P-polarized electromagnetism at the same angle of incidence, or electromagnetic radiation of any polarization at a different angle-of-incidence and Wavelength to the process or Witt ness …

Evaluation Of Irrigation Strategies With The Dssat Cropping System Model, Derek M. Heeren, Hal D. Warner, Todd P. Trooien

Biological Systems Engineering: Papers and Publications

Water is becoming an increasingly valuable commodity with shortages and water rationing more commonplace. Since irrigation is the largest consumptive use of water in South Dakota, accounting for over 70% of the water withdrawals, irrigation water management is critical to make the best use of the water available. This project uses the CERES-Maize cropping system model (available in DSSAT v4) to study the impact of various irrigation management strategies on corn production. SDSU management software developed by Oswald (2006) is used to simulate a center pivot for specific locations and years. Weather data from several sites in the Great Plains …

Flying Mobile On-Board Ellipsometer, Polarimeter, Reflectometer And The Like Systems, Blaine D. Johs,, Ping He, Martin M. Liphardt, Christopher A. Goeden, John A. Woollam, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

A substantially self-contained “on-boar ” material system investigation system functionally mounted on a three dimen sional locational system to enable positioning at desired locations on, and distances from, the surface of a large sample, including the capability to easily and conveniently change the angle-of-incidence of a beam of electromagnetic radiation onto a sample surface.

Wigner Distribution Of A Transducer Beam Pattern Within A Multiple Scattering Formalism For Heterogeneous Solids, Goutam Ghoshal, Joseph A. Turner, Richard Weaver

Department of Engineering Mechanics: Faculty Publications

Diffuse ultrasonic backscatter measurements have been especially useful for extracting microstructural information and for detecting flaws in materials. Accurate interpretation of experimental data requires robust scattering models. Quantitative ultrasonic scattering models include components of transducer beam patterns as well as microstructural scattering information. Here, the Wigner distribution is used in conjunction with the stochastic wave equation to model this scattering problem. The Wigner distribution represents a distribution in space and time of spectral energy density as a function of wave vector and frequency. The scattered response is derived within the context of the Wigner distribution of the beam pattern of …

Electroelastic Effect Of Thickness Mode Langasite Resonators, Haifeng Zhang, Joseph A. Turner, J. S. Yang, J. A. Kosinski

Department of Engineering Mechanics: Faculty Publications

Langasite is a very promising material for resonators due to its good temperature behavior and high piezoelectric coupling, low acoustic loss, and high Q factor. The biasing effect for langasite resonators is crucial for resonator design. In this article, the resonant frequency shift of a thickness-mode langasite resonator is analyzed with respect to a direct current (DC) electric field applied in the thickness direction. The vibration modes of a thin langasite plate fully coated with an electrode are analyzed. The analysis is based on the theory for small fields superposed on a bias in electroelastic bodies and the first-order perturbation …

Acuta Enews October 2007, Vol.36, No. 10

ACUTA Newsletters

ln This lssue

From the President .............. Watt Magnussen, Ph.D., Texas A&M University

Tech Talk: Makin' Bacn: Another Way to Clog lnboxes............... Kevin Tanzillo, Dux PR

DC Update............... Jeanne Jansenius, Sewanee, The University of the South

Board Report ................. Riny Ledgerwood, San Diego State Univ., ACUTA Sec./Treasurer

New Faces at ACUTA

Web Tip: Listserv Reminders ................. Aaron Fuehrer, ACUTA Information Technology Mgr.

Member Sites to See

lnfo Links Randy Hayes, Univ. of Northern lowa

lnvite Your Vendors to Join ACUTA............. Amy Burton, ACUTA Mgr., Membership Mktg.& Corp. Relations

Welcome New Members

Check lt Out: RFls/RFPs, Job Postings, Press Releases