Engineering Commons^™

Comparative Study Of Base-Isolated And Fixed-Base Buildings Using A Damage/Cost Approach, Martin Lashgari

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

High performance base-isolated buildings are designed with a higher level of safety than the conventional fixed-base buildings under the current codes. As a sustainable development, these buildings have considerably lower social and economic impacts in a major event. The main factor limiting the extensive use of such systems is the higher initial construction costs. The cost estimations based on only initial investment may have concluded misleading results as the performance of those systems in earthquakes are different. Therefore, an evaluation considering initial costs and future repair costs due to damages from earthquakes gives a better scope for selection of an …

Assessment And Evaluation Of Timber Piles Used In Nebraska For Retrofit And Rating, Atorod Azizinamini, Alireza Mohammadi, Jawad H. Gull, Ramin Taghinezhad

Nebraska Department of Transportation: Research Reports

No abstract provided.

Universal Breakaway Steel Post For Other Applications, Robert W. Bielenberg, Ronald K. Faller, Karla A. Lechtenberg, Craig W. Price, Tyler L. Schmidt, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Relationship Between Photofixed Condensate, Effluent And Bulk Composition Of Several Common Rtv Materials, Fen Zhou Hanrahan, Natale J. Ianno

Department of Electrical and Computer Engineering: Faculty Publications

Raman spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy are employed to analyze the bulk compositions of five kinds of Room Temperature Vulcanized (RTV) silicones (CV2568, RTV566, DC93-500, SCV2590 and SCV2590-2) that are commonly employed in orbiting spacecraft. It is found that polydimethylsiloxane (PDMS), silicon dioxide, Tetra-n-propylsilicate (NPS), silicic acid, tetraethyl orthosilicate, and trimethylsilanol are contained in all of them. The outgassing products from those silicones are characterized by FTIR. By comparing the position of the peaks, it is found that the outgassing products of each material are PDMS and NPS which are consistent with the compositions of samples determined with …

Biomass Round Bales Infield Aggregation Logistics Scenarios, Cannayen Igathinathane, David Archer, C. Gustafson, Marty Schmer, John Hendrickson, Scott Kronberg, Deepak R. Keshwani, Leslie Backer, Kenneth Hellevang, Timothy Faller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biomass bales often need to be aggregated (collected into groups and transported) to a field-edge stack or a temporary storage before utilization. Several logistics scenarios for aggregation involving equipment and aggregation strategies were modeled and evaluated. Cumulative Euclidean distance criteria evaluated the various aggregation scenarios. Application of a single-bale loader that aggregated bales individually was considered as the “control” scenario with which others were compared. A computer simulation program developed determined bale coordinates in ideal and random layouts that evaluated aggregation scenarios. Simulation results exhibited a “diamond pattern” of bales on ideal layout and a “random pattern” emerged when ≥ …

Biofuels From Crop Residue Can Reduce Soil Carbon And Increase Co2 Emissions, Adam J. Liska, Haishun Yang, Maribeth Milner, Steve Goddard, Humberto Blanco-Canqui, Matthew P. Pelton, Xiao X. Fang, Haitao Zhu, Andrew E. Suyker

Adam Liska Papers

Removal of corn residue for biofuels can decrease soil organic carbon(SOC) and increase CO₂ emissions because residue C in biofuels is oxidized to CO₂ at a faster rate than when added to soil. Net CO2 emissions from residue removal are not adequately characterized in biofuel life cycle assessment (LCA). Here we used a model to estimate CO₂ emissions from corn residue removal across the US Corn Belt at 580 million geospatial cells. To test the SOC model, we compared estimated daily CO₂ emissions from corn residue and soil with CO₂ emissions measured using eddy covariance, …

Uncertainties In Life Cycle Greenhouse Gas Emissions From U.S. Beef Cattle, Quentin M. Dudley, Adam Liska, Andrea K. Watson, Galen E. Erickson

Adam Liska Papers

Beef cattle feedlots are estimated to contribute 26% of U.S. agricultural greenhouse gas (GHG) emissions, and future climate change policy could target reducing these emissions. Life cycle assessment (LCA) of GHG emissions from U.S. grain-fed beef cattle was conducted based on industry statistics and previous studies to identify the main sources of uncertainty in these estimations. Uncertainty associated with GHG emissions from indirect land use change, pasture soil emissions (e.g. soil carbon sequestration), enteric fermentation from cattle on pasture, and methane emissions from feedlot manure, respectively, contributed the most variability to life cycle GHG emissions from beef production. Feeding of …

Integrating Mammalian Hazards With Management At U.S. Civil Airports: A Case Study., Kristin M. Biondi, Jerrold L. Belant, James A. Martin, Travis L. Devault, Guiming Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife incidents with U.S. civil aircraft cost an estimated $1.4 billion from 1990 to 2010, with mammals 5 times more likely to cause damage than other wildlife. We surveyed 2 general aviation (GA) airports and 6 Part-139 certificated (i.e., certified) airports to assess efficacy of management practices for mammalian species hazardous to aircraft. We obtained information on mammalian species present on airport grounds, types and estimated effectiveness of management techniques, and effort spent on wildlife management. We evaluated management techniques relative to aircraft–wildlife collisions (i.e., incident) frequencies taken from Federal Aviation Administration’s (FAA) National Wildlife Strike Database and species hazard …

Position/Speed Sensorless Control For Permanent-Magnet Synchronous Machines, Yue Zhao

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Permanent-magnet synchronous machines (PMSMs) are widely used in industrial applications owing to their distinctive advantages, such as high efficiency, high power density, and wide constant power region. To achieve high-performance field oriented control, accurate rotor position information, which is usually measured by rotary encoders or resolvers, is indispensable. However, the use of these sensors increases the cost, size, weight, and wiring complexity and reduces the mechanical robustness and the reliability of the overall PMSM drive systems. The goal of the research for this dissertation was to develop a rotor position/speed sensorless control system with performance comparable to the sensor-based control …

Towards A Sustainable Modular Robot System For Planetary Exploration, S. G. M. Hossain

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis investigates multiple perspectives of developing an unmanned robotic system suited for planetary terrains. In this case, the unmanned system consists of unit-modular robots. This type of robot has potential to be developed and maintained as a sustainable multi-robot system while located far from direct human intervention. Some characteristics that make this possible are: the cooperation, communication and connectivity among the robot modules, flexibility of individual robot modules, capability of self-healing in the case of a failed module and the ability to generate multiple gaits by means of reconfiguration. To demonstrate the effects of high flexibility of an individual …

Improving The Treatment Of Non-Aqueous Phase Tce In Low Permeability Zones With Permanganate, Chanat Chokejaroenrat, Steve D. Comfort, Chainarong Sakulthaew, Bruce I. Dvoark

Nebraska Water Center: Faculty Publications

Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is aparticularly challenging issue for injection-based remedial treatments. Our objective was to improve thesweeping efficiency of permanganate (MnO4−) into LPZs to treat high concentrations of TCE. This wasaccomplished by conducting transport experiments that quantified the penetration of various perman-ganate flooding solutions into a LPZ that was spiked with non-aqueous phase14C-TCE. The treatments weevaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilizationaids that minimized MnO2rind formation and (iii) a phase-transfer catalyst. In addition, we quantifiedthe ability of these flooding solutions to improve TCE destruction under batch …

Acuta Enews March 2014 Vol. 43, No. 3

ACUTA Newsletters

In this Issue...

1 Board of Directors 2014-15

2 Learning Analytics

3 Annual Conference 2014

4 Members Celebrate Anniversaries

6 WebRTC: DTMF and 911

7 Board Report

7 lt's a Girl!

8 lnfo Links

9 Welcome New Members

9 Check lt Out

Quantifying And Modeling Stream–Aquifer Interactions In The Elkhorn River Basin, Nebraska, Can Liu

School of Natural Resources: Dissertations, Theses, and Student Research

This study combined statistical analyses, field investigations and numerical groundwater flow modeling to quantify the connectivity between the Elkhorn River and its adjacent aquifers in Nebraska. The Mann-Kendall trend tests were conducted to detect increasing or decreasing tendencies on the time series data of streamflow, which were collected from eighteen gauging stations in the Elkhorn River and its tributaries. Decreasing trends were not found in the annual streamflow data.

Field investigation of streambed hydraulic properties was performed in the Elkhorn River near Winslow and Norfolk. Vertical hydraulic conductivities (K_v) of the shallow streambed sediments were obtained by …

Stormwater Pollution Treatment Bmp Discharge Structures, Miles F. Simmons, David M. Admiraal

Nebraska Department of Transportation: Research Reports

No abstract provided.

Dynamic Testing Of A Non-Proprietary, High-Tension, Cable End Terminal System, Ronald K. Faller, Dean L. Sicking, Jennifer D. Schmidt, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Effectiveness Study Of Unl's Pneumatic Crack/Joint Preparation Device, Yong Cho, Changbum Ahn

Nebraska Department of Transportation: Research Reports

No abstract provided.

Passive Biaxial Mechanical Properties And In Vivo Axial Pre-Stretch Of The Diseased Human Femoropopliteal And Tibial Arteries, Alexey Kamenskiy, Iraklis I. Pipinos, Yuris A. Dzenis, Clay Lomneth, Syed A. Jaffar Kazmi, Nicholas Y. Phillips, Jason N. Mactaggart

Department of Mechanical and Materials Engineering: Faculty Publications

Surgical and interventional therapies for atherosclerotic lesions of the infrainguinal arteries are notorious for high rates of failure. Frequently, this leads to expensive reinterventions, return of disabling symptoms, or limb loss. Interaction between the artery and repair material likely plays an important role in reconstruction failure, but data describing the mechanical properties and functional characteristics of human femoropopliteal and tibial arteries are currently not available. Diseased superficial femoral (SFA, n=10), popliteal (PA, n=8), and tibial arteries (TA, n=3) from 10 patients with critical limb ischemia were tested to determine passive mechanical properties using planar biaxial extension. All …

Methods, Systems, And Devices For Surgical Access And Inserton, Tom Frederick, Shane Farritor, Jack Mondry, Eric Markvicka, Dmitry Oleynikov, Jacob Greenburg

Department of Mechanical and Materials Engineering: Faculty Publications

The various embodiments herein relate to systems, devices, and/or methods relating to Surgical procedures, and more specifically for accessing an insufflated cavity of a patient and/or positioning Surgical systems or devices into the cavity.

Systemand Method For Controlling Motion Of Spacecrafts, Piyush Grover, Christian Andersson

Department of Mechanical and Materials Engineering: Faculty Publications

A motion of an object is controlled from a geostationary transit orbit (GTO) of an earth to an orbit of a moon. A first trajectory of the motion of the object is determined from an intermediate orbit of an earth to a neighborhood of a stable manifold of a first Lagrange point (L1). A second trajectory of the motion of the object is determined from the GTO to the intermediate orbit. A third trajectory of the motion of the object is determined from the neighborhood to the stable manifold to an L1 orbit, and a fourth trajectory of the motion …

Identification Of Wheat Varieties With A Parallel-Plate Capacitance Sensor Using Fisher’S Linear Discriminant Analysis, C. V. K. Kandala, George Meyer, N. Puppala, V. Settaluri, R. S. Reddy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Fisher’s linear discriminant (FLD) models for wheat variety classification were developed and validated. The inputs to the FLD models were the capacitance (𝐶), impedance (𝑍), and phase angle (𝜃), measured at two frequencies. Classification of wheat varieties was obtained as output of the FLDmodels.𝑍and 𝜃of a parallel-plate capacitance system,holding thewheat samples, weremeasured using an impedance meter, and the 𝐶 value was computed.The best model developed classified the wheat varieties, with accuracy of 95.4%, over the six wheat varieties tested.This method is simple, rapid, and nondestructive and would be useful for the breeders and the peanut industry.

Contrast Enhancement Using Silica Microspheres In Coherent Anti-Stokes Raman Spectroscopic Imaging, X. Huang, X. N. He, W. Xiong, Y. Gao, L. J. Jiang, Li Liu, Y. S. Zhou, L. Jiang, J. F. Silvain, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Coherent anti-Stokes Raman scattering (CARS) microscopy is a powerful imaging technique that can provide chemical information of organic and nonorganic materials through vibrational spectroscopy. However, its contrast is not sufficient for monitoring thin film materials. In this study, silica microspheres were employed for enhancing the signal contrast in CARS imaging. One layer of optically transparent silica microspheres was self-assembled onto polymer grating samples to enhance the CARS signals. The highest contrast enhancement factor of 12.5 was achieved using 6.1-μm-diameter microspheres. Finite-difference timedomain method (FDTD) simulation was conducted to simulate the contrast enhancement with silica microspheres of different diameters.

Acuta Enews February 2014 Vol. 43, No. 2

ACUTA Newsletters

In this Issue.,.

1 Benefitting from ACUTA

2 Thanks to Fall Seminar Exhibitors dt Sponsors

3 Collaboration Is Not Automatic

4 Webinar: IAM

5 Board Report

5 Discounted Dallas Mavericks Tickets

6 Two Top Legislatiott Issues Facing Higher Ed

7 lnfo Links

8 Welcome New Members

8 Check It Out

Safety Performance Evaluation Of Weak-Post, W-Beam Guardrail Attached To Culvert, Scott K. Rosenbaugh, Ronald K. Faller, Dean L. Sicking, Karla A. Lechtenberg, Allison J. Schneider, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Comprehensive Evaluation Of Fracture Critical Bridges, Aaron Jon Yakel, Atorod Azizinamini, Huy Pham, Saeed Doust

Nebraska Department of Transportation: Research Reports

No abstract provided.

Berm Method For Quantification Of Infiltration At The Plot Scale In High Conductivity Soils, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Measuring infiltration at the plot scale is difficult, especially for high hydraulic conductivity soils. At the plot scale, the infiltration rate is usually calculated by comparing surface runoff to rainfall. Direct measurement of infiltration beyond the point scale is typically limited to locations where land forming (e.g., infiltration pond) has been performed or fields with basin irrigation systems. The standard method for field measurement of point-scale infiltration is the double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water-filled 15-cm diameter …

Large-Scale Solution Synthesis Of Narrow Graphene Nanoribbons, Timothy H. Vo, Mikhail Shekhirev, Donna A. Kunkel, Martha D. Morton, Eric Berglund, Lingmei Kong, Peter M. Wilson, Peter A. Dowben, Axel Enders, Alexander Sinitskii

Nebraska Center for Materials and Nanoscience: Faculty Publications

According to theoretical studies, narrow graphene nanoribbons with atomically precise armchair edges and widths of(1.1 eV), which makes them potentially promising for logic applications. Different top–down fabrication approaches typically yield ribbons with width >10nm and have limited control over their edge structure. Here we demonstrate a novel bottom–up approach that yields gram quantities of high-aspect-ratio graphene nanoribbons, which are only ~1 nm wide and have atomically smooth armchair edges. These ribbons are shown to have a large electronic bandgap of ~1.3 eV, which is significantly higher than any value reported so far in experimental studies of graphene nanoribbons prepared by …

Providing Flexible File-Level Data Filtering For Big Data Analytics, Lei Xu, Ziling Huang, Hong Jiang, Lei Tian, David Swanson

School of Computing: Technical Reports

The enormous amount of big data datasets impose the needs for effective data filtering technique to accelerate the analytics process. We propose a Versatile Searchable File System, VSFS, which provides a transparent, flexible and near real-time file-level data filtering service by searching files directly through the file system. Therefore, big data analytics applications can transparently utilize this filtering service without application modifications. A versatile index scheme is designed to adapt to the exploratory and ad-hoc nature of the big data analytics activities. Moreover, VSFS uses a RAM-based distributed architecture to perform file indexing. The evaluations driven by three real-world analytics …

Influence Of Grass Hedges On The Transport Of Antimicrobials, Antimicrobial Resistance Genes, And Antimicrobial Resistant Pathogens After Land Application Of Swine Manure, Shannon L. Bartelt-Hunt

Department of Civil and Environmental Engineering: Faculty Publications

The objective of this study was to determine the effects of narrow grass hedges on the fate and transport of antimicrobials and antimicrobial resistance genes (ARGs) in runoff and in soil following the land application of swine manure slurry. Swine manure slurry was land applied to 0.75m wide by 4.0m long plots established on an Aksarben silty clay loam soil located in southeast Nebraska. Swine manure was applied at a rate to meet the 3-year nitrogen (N) requirements for corn. Swine manure was applied to plots with and without a narrow grass hedge to evaluate the effect of the hedge …

Application Of Isothermal Calorimetry To Phosphorus Sorption Onto Soils In A Flow-Through System, Chad Penn, Derek M. Heeren, Garey A. Fox, Ajay Kumar

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The degree, mechanisms, and kinetics of phosphorus (P) sorption onto soils can have a significant influence on leaching losses of P from soil. The objectives of this study were to measure the impact of retention time (RT) on P sorption in a flow-through system intended to simulate downward movement of a P solution through two different riparian soils, and determine if isothermal titration calorimetry (ITC) can provide useful information reflective of flow-through results. Topsoil from two riparian/alluvial sites (Barren Fork and Clear Creek) was sampled and characterized for P concentrations and parameters related to P sorption. Flow-through P sorption experiments …

A Cost Effective Method To Create Accurate Engine Performance Maps & Updating The Nebraska Pumping Plant Performance Criteria, Jacob K. Keller

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The objective of this paper was to develop a simplified process to create engine performance maps using tractor test data and theoretical modeling techniques. Performance maps for industrial engines can greatly simplify the process of matching engines to their various applications in the most economical way. However, a common performance graph supplied by a manufacturer typically only includes a single performance curve across the range of an engine’s operating speed. The single curve is good for some applications but lacks the needed performance detail at operating conditions other than shown on the performance curve. Extensive testing and resources are required …