Engineering Commons^™

Study Of The Growth And Switching Kinetics On Ferroelectric Nanocrystals Of Copolymer Vinylidene Fluoride And Trifluoroethylene On An Atomic Force Microscope, R. V. Gaynutdinov, O. A. Lysova, A. L. Tolstikhina, V. M. Fridkin, S. G. Yudin, Stephen Ducharme

Stephen Ducharme Publications

The growth of nanocrystals obtained from Langmuir-Blodgett films of ferroelectric copolymer consisting of 70% vinylidene fluoride and 30% trifluoroethylene has been investigated by atomic force microscopy (AFM). The radius and concentration of nanocrystals are found to depend on the annealing time of the film. A model for nanocrystal growth is proposed which yields adequate time dependences for nanocrystal size parameters. The switching kinetics of individual ferroelectric nanocrystals with an average diameter of 100–200 nm and a height of 15–20 nm has been investigated in the piezoelectric response mode. It is shown that the switching of nanocrystals has an activation character.

Preparing Nebraska Future Water Leaders: Nwla Academy Class Iii (2013), Connie I. Reimers-Hild

Nebraska Water Leaders Academy: Publications and Materials

Group communications, Phyllis Schoenholz, UNL

Communication and transformational leadership. Dr. Mark Burbach and Dr. Connie Reimers-Hild, UNL

Nebraska's instream flow laws and applications, Ann Bleed, board member, Lower Platte Natural Resources District

River Basin Compacts; Nebraska's obligations, Michael Jess, water resources engineer; consultant.

Conservation along the Central Platte, Mark Peyton, senior biologist, Central Nebraska Public Power and Irrigation District

Central Platte River water issues in regard to habitat for endangered species, Jason Farnsworth, natural resources specialist, Headwaters Corporation & Jerry Kenny, executive director of the Platte River Recovery Implementation Program

Rowe Sanctuary; discussion and viewing …

Acuta Enews March 2013 Vol. 42, No. 3

ACUTA Newsletters

In this issue...

1 Meet the 2014 Board

2 Connexity

3 What's on Your Desk?

3 New State/Province Coordinators

4 Second Annuall ResNet Report The App Is Back-Better than Ever!

5 Info Links

6 Members Celebrate Anniversaries

8 FCC 6 the Enterprise

9 Congratulation to Brian Yamaguchi

10 Board Report

10 Compliance Alliance: First Anniversary

11 Welcome New Members

11 Check It Out

High-Stress Shear-Induced Crystallization In Isotactic Polypropylene And Propylene/Ethylene Random Copolymers, Zhe Ma, Lucia Fernandez-Ballester, Dario Cavallo, Tim Gough, Gerrit W. M. Peters

Department of Mechanical and Materials Engineering: Faculty Publications

Crystallization of an isotactic polypropylene (iPP) homopolymer and two propylene/ethylene random copolymers (RACO), induced by high-stress shear, was studied using in situ synchrotron wide-angle X-ray diffraction (WAXD) at 137 °C. The “depth sectioning” method (Fernandez-Ballester, Journal of Rheology 53:5 (2009), pp. 1229−1254) was applied in order to isolate the contributions of different layers in the stress gradient direction and to relate specific structural evolution to the corresponding local stress. This approach gives quantitative results in terms of the specific length of fibrillar nuclei as a function of the applied stress. As expected, crystallization becomes faster with increasing stress—from the inner …

Relationships Between Unoccupied Classroom Acoustical Conditions And Elementary Student Achievement Measured In Eastern Nebraska, Lauren M. Ronsse, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Building standards recommend maximum background noise levels (BNL) and reverberation times (RT) for unoccupied classrooms. However, existing research does not show a consistent correlation between these parameters and student achievement. Through in situ testing, this research seeks to determine what acoustical conditions should be attained in elementary schools for students to meet educational goals. Acoustical measurements were conducted in a Nebraska public school system and correlated to achievement scores from students in the surveyed classrooms. Unoccupied BNLs and RTs were gathered in 34 third and 33 fifth-grade classrooms. Additionally, binaural room impulse response measurements were gathered in a subset of …

Test Advising Framework, Yurong Wang

School of Computing: Dissertations, Theses, and Student Research

Test cases are represented in various formats depending on the process, the technique or the tool used to generate the tests. While different test case representations are necessary, this diversity challenges us in comparing test cases and leveraging strengths among them - a common test representation will help.

In this thesis, we define a new Test Case Language (TCL) that can be used to represent test cases that vary in structure and are generated by multiple test generation frameworks. We also present a methodology for transforming test cases of varying representations into a common format where they can be matched …

Acuta Enews February 2013 Vol. 42, No. 2

ACUTA Newsletters

In this issue...

1 Meeting Member Needs with Excellence

2 Remembering Luther Robb

2 New Phone System for ACUTA Office

3 Info Links

3 Look, Everybody: Lori's Back!

4 What's on Your Desk Today?

5 Why Fax over IP Fails

6 Networks and a Single Point of Failure

7 Turning Big Data into Big ldeas

7 Thanks to Journal Advertisers for 2012

8 Board Report

8 Bring 8 Winter Seminar Sessions to Your Desktop or Tablet

8 Thanks to Winter 2013 Seminar Exhibitors and Sponsors

9 Welcome New Members

9 Check It Out

Room-Temperature Organic Ferromagnetism In The Crystalline Poly(3-Hexylthiophene): Phenyl-C61-Butyric Acid Methyl Ester Blend Film, Bin Yang, Zhengguo Xiao, Yongbo Yuan, Tanjore V. Jayaraman, Jeffrey E. Shield, Ralph Skomski, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Pronounced ferromagnetism was observed in a crystalline blend film of conjugated polymer poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) by using magnetic force microscopy measurements. A substantial room-temperature saturation magnetization of about 0.65 emu g−1 was measured by an alternating gradient field magnetometer. Multiple experimental evidences demonstrate the charge transfer from the P3HT to the PCBM and the formation of P3HT crystal domain are expected to be two critical factors for the originals of room-temperature organic ferromagnetism.

2013 Nebraska Water Monitoring Programs Report, Marty Link, Joe Kenning

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain good quality water and encourage or execute activities to improve poor water quality. Monitoring is done on the over 16,000 miles of flowing rivers and streams, our greater than 148,000 acres of surface water in lakes and reservoirs, and the vast storage of groundwater in Nebraska’s aquifers.

Development Of A Field Test Method For Total Suspended Solids Analysis, Tian Zhang, John S. Stansbury, Jessica Branigan

Mid-America Transportation Center: Final Reports and Technical Briefs

Total suspended solids (TSS) are all particles in water that will not pass through a glass fiber filter with a pore size less than 2 μm, including sediments, algae, nutrients, and metals. TSS is an important water quality parameter because of its adverse effects on aquatic species and wildlife. TSS is regulated through the EPA via the NPDES in many states. Since there are no accepted field tests for TSS, projects with TSS regulations must send samples to a laboratory for analysis, which can delay projects for days or weeks. The goal of this research was to develop a rapid, …

Calibration Of Work Zone Impact Analysis Software For Missouri, Praveen Edara Ph.D., P.E., Ptoe, Carlos Sun Ph.D., P.E., Jd, Zhongyuan Zhu

Mid-America Transportation Center: Final Reports and Technical Briefs

This project calibrated two software programs used for estimating the traffic impacts of work zones. The WZ Spreadsheet and VISSIM programs were recommended in a previous study by the authors. The two programs were calibrated using field data from two work zones in Missouri. Both work zones involved a single lane closure on a three-lane section of roadway. The I-44 work zone was a long-term work zone, while the I-70 work zone was temporary, lasting only a few hours. The capacity values required for calibration were nearly identical for the two programs: 1,575 veh/hr/ln for the WZ Spreadsheet and 1,514 …

Investigation Of Alternative Work Zone Merging Sign Configurations, Praveen Edara Ph.D., P.E., Ptoe, Zhongyuan Zhu, Carlos Sun Ph.D., P.E., Jd

Mid-America Transportation Center: Final Reports and Technical Briefs

This study investigated the effect of an alternative merge sign configuration within a freeway work zone. In this alternative configuration, the graphical lane closed sign from the MUTCD was compared with a MERGE/arrow sign on one side and a RIGHT LANE CLOSED sign on the other side. The study measured driver behavior characteristics including speeds and open lane occupancies. The measurements were taken at two identical work zones on I-70 in Missouri, one with the new test sign and the other with the standard MUTCD sign. The study found that the open lane occupancy upstream of the merge sign was …

Development Of A Guide For Prioritization Of Railway Bridges For Repair And Replacement, Anna Maria Rakoczy, Andrzej S. Nowak

Mid-America Transportation Center: Final Reports and Technical Briefs

The objective of this study was to develop evaluation bases for the repair, rehabilitation, and replacement of existing railway bridges. Considering the importance of bridges to the railway network, the research involved the review and analysis of major factors that influence structural performance, e.g., degree of corrosion, loss of material (section loss, holes), fatigue problems, and loose connections. In particular, the research focused on connections, and their importance relative to the evaluation of bridge performance. The relationship between various conditions and the ability to perform the required function (i.e., carry a freight train) was established in the form of maximum …

Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre

Daugherty Water for Food Global Institute: Faculty Publications

In 1950 the global population was just over 2.5 billion. Now, in 2013, it is around 7 billion. Although population growth is slowing, the world is projected to have around 9.6 billion inhabitants by 2050. Most of the population increase will be in developing countries where food is often scarce, and land and water are under pressure. To feed the global population in 2050 the world will have to produce more food without significantly expanding the area of cultivated land and, because of competition between a greater number of water users, with less freshwater. On top of land and water …

Calibration Of The Highway Safety Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Henry Brown Msce, P.E., Praveen Edara Ph.D., P.E., Boris Carlos, Kyuongmin Andrew Nam

Mid-America Transportation Center: Final Reports and Technical Briefs

The new Highway Safety Manual (HSM) contains predictive models that need to be calibrated to local conditions. This calibration process requires detailed data types, such as crash frequencies, traffic volumes, geometrics, and land-use. The HSM does not document in detail techniques for gathering such data, since data systems vary significantly across states. The calibration process also requires certain decisions, such as the correct sampling approach, determination of the minimum segment length, the treatment of left-turn phasing, and the inclusion or exclusion of speed-change lane crashes. This report describes the challenges, practical solutions, and results from a statewide HSM calibration in …

Reducing Uncertainty In Fatigue Life Limits Of Turbine Engine Alloys, J M. Larson, S K. Jha, C J. Szczepanski, M J. Caton, R John, A H. Rosenberger, D J. Buchanan, P J. Golden, J R. Jira

United States Air Force: Publications

In probabilistic design of materials for fracture-critical components in modern military turbine engines, a typical maximum design target risk (DTR) is 5 X 10^-8 component failures/engine flight hour. This metric underscores the essential role of safety in a design process that simultaneously strives to achieve performance, efficiency, reliability, and affordability throughout the life cycle of the engine. Traditionally, the design and life management approaches for engine materials have typically relied on extensive testing programs to produce large databases of fatigue data, from which statistically based life limits are derived by extrapolation from the mean fatigue behavior. However, we …

Stability And Power Optimality In Time-Periodic Flapping Wing Structures, Bret Stanford, Philip Beran, Richard Snyder, Mayuresh Patil

United States Air Force: Publications

This paper investigates the nonlinear dynamics of a vehicle with two flexible flapping wings. The body dynamics and the wings' deformation are monolithically grouped into a single system of equations, with aerodynamics accounted for by a quasi-steady blade element method. A periodic shooting method is then used to locate closed orbits of this non-autonomous system, and Floquet multipliers assess the linearized stability about the nonlinear orbit. This framework is then exposed to a gradient based optimizer, in order to quantify the role of wing planform variables, wing structure variables, and kinematic actuation variables in obtaining vehicles with superior open-loop stability …

Maintaining The Master International Frequency Register, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

The present paper is the written elaboration of a presentation held under the same title at the workshop “International Regulations of Space Communications” held in Luxembourg on 24 and 25 May 2012. Consequently, the topic of this paper, the maintenance of the Master International Frequency Register as a key tool for allowing satellite communications to be a viable international sector of space activities, is viewed through the looking glass of the session title, “WRC-12 from the Perspective of International Telecommunications Law.”

In other words, it does not purport to deal with the actual details of maintaining the Register …

Test 2064: Kubota M135gx, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Evapotranspiration And Surface Energy Balance Of A Common Reed-Dominated Riparian System In The Platte River Basin, Central Nebraska, Isa Kabenge, Suat Irmak, John E. Gilley, George E. Meyer, Stevan Z. Knezevic, Timothy J. Arkebauer, Duane Woodward, Milton Moravek

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Quantifying actual evapotranspiration (ET_a) of riparian zones is important for more robust water balance analyses that will enable better planning, managing, and allocating of water resources as well as developing strategies to protect delicate riparian ecosystem functions. The ET_a, sensible heat flux (H), net radiation (R_n), soil heat flux (G), meteorological variables (air temperature, T_a; incoming shortwave radiation, R_s; wind speed, u₃; relative humidity, RH; vapor pressure deficit, VPD; precipitation, etc.), and albedo were measured on an hourly time step, and leaf area index (LAI) and plant height …

Structure And Properties Of Cocoons And Silk Fibers Produced By Attacus Atlas, Narendra Reddy, Yi Zhao, Yiqi Yang

Department of Textiles, Merchandising and Fashion Design: Faculty Publications

Silk fibers in the three layers of Attacus atlas (A. atlas) cocoons have morphological structure and tensile properties similar to that of Bombyx mori silk. Attempts are being made to produce silk for commercial applications from cocoons of relatively unknown wild insects due to the unique properties of the fibers and as a source of income and employment. In this research, A. atlas cocoons were used to study the chemical composition, morphology, physical structure and tensile properties of the silk fibers in the cocoons and ability of the fibers to support the attachment and proliferation of mouse fibroblast cells. It …

Nuts & Bolts, Volume 1, Issue 2

Friends of the Larsen Tractor Museum

New Exhibit Opens
Bill Splinter Memorial
Museum Needs
Fun Facts ... and other non-sense
From Lou's Desk by lou leviticus
Flipping A Fordson
What I've Learned notes from the manager
Museum Updates
Nuts & Bolts Staff:
Museum Guidance Committee:

Direct Flutter And Limit Cycle Computations Of Highly Flexible Wings For Efficient Analysis And Optimization, Bret Stanford, Philip Beran

United States Air Force: Publications

The usefulness of flutter as a design metric is diluted for wings with destabilizing (softening) nonlinearities, as a stable high-amplitude limit cycle (subcritical) may exist for flight speeds well below the flutter point. It is thus desired to design aeroelastic structures such that the post-flutter behavior is as benign (i.e., supercritical) as possible, among the other constraints commonly considered in the optimization process. In order to account for these metrics in an accurate and efficient manner, direct tools are utilized to first locate the Hopf-point (flutter speed), and then to obtain a nonlinear perturbation solution via the method of multiple …

A Mathematical Evaluation Of Hemodynamic Parameters After Carotid Eversion And Conventional Patch Angioplasty, Alexey Kamenskiy, Iraklis I. Pipinos, Yuris A. Dzenis, Prateek K. Gupta, Syed A. Jaffar Kazmi, Jason N. Mactaggart

Department of Mechanical and Materials Engineering: Faculty Publications

Carotid endarterectomy has a long history in stroke prevention, yet controversy remains concerning optimal techniques. Two methods frequently used are endarterectomy with patch angioplasty (CEAP) and eversion endarterectomy (CEE). The objective of this study was to compare hemodynamics-related stress and strain distributions between arteries repaired using CEAP and CEE. Mathematical models were based on in vivo three-dimensional arterial geometry, pulsatile velocity profiles, and intraluminal pressure inputs obtained from 16 patients with carotid artery disease. These data were combined with experimentally derived nonlinear, anisotropic carotid artery mechanical properties to create fluid-structure interaction models of CEAP and CEE. These models were then …

Effects Of Mode Coupling On The Admittance Of An At-Cut Quartz Thickness-Shear Resonator, Huijing He, Jiashi Yang, Wei-Ping Zhang, Ji Wang

Department of Mechanical and Materials Engineering: Faculty Publications

We study the effects of couplings to flexure and face-shear modes on the admittance of an AT-cut quartz plate thickness-shear mode resonator. Mindlin’s two-dimensional equations for piezoelectric plates are employed. Electrically forced vibration solutions are obtained for three cases: pure thickness-shear mode alone; two coupled modes of thickness shear and flexure; and three coupled modes of thickness shear, flexure, and face shear. Admittance is calculated and its dependence on the driving frequency and the length/thickness ratio of the resonator is examined. Results show that near the thickness-shear resonance, admittance assumes maxima, and that for certain values of the length/thickness ratio, …

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe

Department of Mechanical and Materials Engineering: Faculty Publications

The mechanical behavior of TiO₂ nanoparticle-reinforced resin-based dental composites was characterized in this work using a three-dimensional nanoscale representative volume element. The impacts of nanoparticle volume fraction, aspect ratio, stiffness, and interphase zone between the resin matrix and nanoparticle on the bulk properties of the composite were characterized. Results clearly demonstrated the mechanical advantage of nanocomposites in comparison to microfiber-reinforced composites. The bulk response of the nanocomposite could be further enhanced with the increased nanoparticle volume fraction, or aspect ratio, while the influence of nanoparticle stiffness was minimal. The effective Young’s modulus and yield strength of the composite was …

Nebraska Summary: S922 Massey Ferguson 7615, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: 913 Challenger Mt525d, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 2062: Challenger Mt765d, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Investigation Of Synergistic Effects Of Warm Mix Asphalt And High Fractionated Reclaimed Asphalt For Safe, Environmentally Sustainable Highway, Hosin David Lee Ph.D., P.E., Taha Ahmed Msc, E.I.

Mid-America Transportation Center: Final Reports and Technical Briefs

To increase RAP materials by up to 75% by binder replacement, a fractionation method was applied to the RAP stockpile by discarding RAP materials passing No. 16 sieve. This fractionation method was effective in improving volumetric properties of the HMA mixture with high RAP contents. The mix designs were then performed for both HMA and WMA with varying fractionated RAP amounts accounting for a replacement of 20, 30, 40, 50 and 75% of the mixture’s optimum asphalt binder content. All mix designs met the Iowa DOT mix design requirements except the one with 75% RAP materials by binder replacement due …