Engineering Commons^™

U.S. Army Corps Of Engineers Omaha District Monthly Drought Report, November 2006

United States Army Corps of Engineers, Omaha District

Current Conditions

Drought Outlook

Ft. Peck, Montana

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Noxious Weeds Overview

Cultural Resources Overview

Garrison, North Dakota

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Boat Ramp Information

Noxious Weeds Overview

Cultural Resources Overview

Other Areas of Interest/Concern

Oahe, South Dakota

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Noxious Weeds Overview

Cultural Resources Overview

Mainstem Reservoir Information, Weekly Elevation Comparison 7 AUG 2006 through 28 AUG 2006

Mainstem Reservoir Storage Comparison Water Years 2004, 2005, 2006

Ft. Peck, MT

Garrison, ND

Oahe, SD

Modeling, Analysis, And Experimental Study Of In Vivo Wheeled Robotic Mobility, Mark E. Rentschler, Jason Dumpert, Stephen R. Platt, Karl Iagnemma, Dmitry Oleynikov, Shane M. Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

Laparoscopy is abdominal surgery performed with long tools inserted through small incisions. The use of small incisions reduces patient trauma, but also eliminates the surgeon’s ability to view and touch the surgical environment directly. These limitations generally restrict the application of laparoscopy to procedures less complex than those performed during open surgery. This paper presents a theoretical and experimental analysis of miniature, wheeled, in vivo robots to support laparoscopy. The objective is to develop a wireless mobile imaging robot that can be placed inside the abdominal cavity during surgery. Such robots will allow the surgeon to view the surgical environment …

Circular Ultrasound Compounding By Designed Matrix Weighting, Gregory Bashford, Jonathan Morse

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Spatial compounding is an imaging technique that aims to improve image contrast by combining partially decorrelated images acquired at different angles or positions. In conventional spatial compounding, data sets are combined with equal weighting. Here, we describe an alternative method of reconstruction using algorithms which weight the data based on a “quality” matrix. The quality matrix is derived from beam-forming characteristics. For each data set, the reliability of the data is assumed to vary spatially. By compounding the data based on the quality matrix, a complete image is formed. Here, we describe the construction of a rotational translation stage and …

Variable Upper And Lower Crop Water Stress Index Baselines For Corn And Soybean, J. O. Payero, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Upper and lower crop water stress index (CWSI) baselines adaptable to different environments and times of day are needed to facilitate irrigation scheduling with infrared thermometers. The objective of this study was to develop dynamic upper and lower CWSI baselines for corn and soybean. Ten-minute averages of canopy temperatures from corn and soybean plots at four levels of soil water depletion were measured at North Platte, Nebraska, during the 2004 growing season. Other variables such as solar radiation (R_s), air temperature (T_a), relative humidity (RH), wind speed (u), and plant canopy height (h) were …

Use Of Time Domain Reflectometry For Continuous Monitoring Of Nitrate-Nitrogen In Soil And Water, J. O. Payero, David D. Tarkalson, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nitrate-Nitrogen (NO₃-N) losses to ground and surface water are an environmental and agronomic concern in modern crop production systems in the Central Great Plains. Monitoring techniques for nitrogen use in agricultural production are needed to increase crop yield, optimize nitrogen use, and reduce NO₃-N leaching. Time domain reflectometry (TDR) could potentially be calibrated to continuously measure NO₃-N in soil and water. The objectives of this study were to: (1) evaluate the effect of different factors affecting the response of the bulk electrical conductivity (ECb) sensed by TDR, (2) compare the sensitivity and differences between …

Land Application Of Manure For Beneficial Reuse, L. M. Risse, M. L. Cabrera, A. J. Franzluebbers, J. W. Gaskin, John E. Gilley, R. Killorn, D. E. Radcliffe, W. E. Tollner, H. Zhang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The concentration of animal production systems has increased efficiency and improved overall economic return for animal producers. This concentration, along with the advent of commercial fertilizers, has led to a change in the way animal producers view manure. Manure, once valued as a resource by farmers, is now treated as a waste. Air and water quality concerns that arise primarily from the under-utilization or inefficient use of manure contribute to these changing views. However, when properly used, manure is a resource and should be regulated as such. In the United States, the USDA/EPA Unified National Strategy for Animal Feeding Operations …

Properties Of Chitosan Films As A Function Of Ph And Solvent Type, Ki Myong Kim, Jeong Hwa Son, Sung-Koo Kim, Curtis L. Weller, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Two different deacetylated chitosans were dissolved in formic, acetic, lactic, or propionic acid to prepare chitosan films. The pH values of the film-forming solutions were adjusted to 3, 4, and 5. Water vapor permeability (WVP), tensile strength (TS), elongation (E), and total soluble matter (TSM) were significantly (P < 0.05) affected by acid type, pH, and degree of deacetylation (DA). Low DA (LDA) chitosan films had lower WVP and TSM, higher TS compared with high DA (HDA) chitosan films. The E values were not affected by DA. As pH increased, WVP and TSM of chitosan films tended to increase while TS decreased significantly (P < 0.05). Chitosan films with acetic and propionic acid solvents had low WVP and TSM and high TS, while films with lactic acid solvent had high E and TSM and the lowest TS. Fourier-transform infrared showed peak shifting in the spectra with different solvents and at different pH values. Chitosan films with lactic acid solvent showed a peak shift to a lower frequency range. The NH3+ band was absent in the pH 5.0 chitosan film spectra.

Modeling Of Transport Phenomena And Melting Kinetics Of Starch In A Co-Rotating Twin-Screw Extruder, Lijun Wang, David D. Jones, Curtis L. Weller, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A mathematical model was developed to simulate fluid flow, heat transfer, and melting kinetics of starch in a co-rotating intermeshing twin-screw extruder (TSE). The partial differential equations governing the transport phenomena of the biomaterial in the extruder were solved by a finite element scheme. For validating the model, the predicted product pressure, bulk temperature at the entrance of the die, and minimum residence time of the biomaterial in the extruder were compared with experimental data. Standard errors of product pressure, bulk temperature at the die entrance, and minimum residence time were about 8.8, 2.8, and 17.3%. Simulations were carried out …

Impact Of Tillage And Placement Of Terbufos Insecticide Runoff, Mitiku Mamo, William L. Kranz, Elaine R. Douskey, Shripat T. Kamble, John F. Witkowski

Department of Agricultural and Biological Systems Engineering: Faculty Publications

On a national scale, the damage caused by corn rootworm (Diabrotica virgifera virgifera LeConte), can cause economic loss of up to $650 million annually. To limit these losses, corn producers apply terbufos insecticide to approximately 11% of all corn acres at a time when there is a high probability of intense precipitation. When combined with low vegetative cover and disturbed soil surfaces, there is a high potential for terbufos transport into surface water bodies. Increased public concern for environmental contamination from the use of agricultural chemicals has prompted many crop growers to look for crop production practices that minimize …

Nonintrusive Mapping Of Near-Surface Preferential Flow, R. S. Freeland, Lameck O. Odhiambo, J. S. Tyner, J. T. Ammons, W. C. Wright

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A unique survey protocol has been developed that maps near-subsurface preferential flow using integrated ground-penetrating radar (GPR) and a differential geographical positioning system (DGPS). The survey protocol consists of a mobile GPR system that spirals outward along a prescribed course, continuously gathering subsurface data for an extended period. Metered water is applied to a centrally located water-ponding ring, after first capturing the initial dry-state pattern signatures. The water radiates outward beneath the surface as it follows preferential flow pathways, which the GPR instrumentation spiraling above highlights. After data are collected, pre- and post-water time-elapsed images profiles are segmented by pattern …

Purification And Scale-Up Of A Recombinant Heavy Chain Fragment C Of Botulinum Neurotoxin Serotype E In Pichia Pastoris Gs115, Michael P. Dux, Rick Barent, Jayanta Sinha, Mark Gouthro, Todd Swanson, Ardis Barthuli, Mehmet Inan, John T. Ross, Leonard A. Smith, Theresa J. Smith, Robert Webb, Bonnie Loveless, Ian Henderson, Michael M. Meagher

Michael Meagher Publications

A recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype E (BoNT/E) is proposed as a vaccine against the serotype E neurotoxin. This fragment, rBoNTE(H_c), was produced intracellular in Pichia pastoris GS115 by a three-step fermentation process, i.e., glycerol batch phase and a glycerol fed-batch phase to achieve high cell densities, followed by a methanol fed-batch induction phase. The rBoNTE(H_c) protein was purified from the soluble fraction of cell lysates using three ion-exchange chromatography steps (SP Sepharose Fast Flow, Q Sepharose Fast Flow, Sp Sepharose High Performance) and polished with a hydrophobic charge induction chromatography step …

Dissolution Kinetics Of High Explosives Particles In A Saturated Sandy Soil, Matthew C. Morley, Hiroshi Yamamoto, Gerald E. Speitel, Jr., Jay Clausen

Department of Civil and Environmental Engineering: Faculty Publications

Solid phase high explosive (HE) residues from munitions detonation may be a persistent source of soil and groundwater contamination at military training ranges. Saturated soil column tests were conducted to observe the dissolution behavior of individual components (RDX, HMX, and TNT) from two HE formulations (Comp B and C4). HE particles dissolved readily, with higher velocities yielding higher dissolution rates, higher mass transfer coefficients, and lower effluent concentrations. Effluent concentrations were below solubility limits for all components at superficial velocities of 10–50 cm day^-1. Under continuous flow at 50 cm day^-1, RDX dissolution rates from Comp …

Detection Of Inclement Weather Conditions At A Signalized Intersection Using A Video Image Processing Algorithm, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta, James V. Krogmeier

Department of Civil and Environmental Engineering: Faculty Publications

Inclement weather conditions like snowfall adversely affect traffic flow characteristics, necessitating a change in parameters that define the operation of a signalized intersection. A weather-based timing plan selection is needed to maintain a desirable level of operational efficiency. Automatic implementation of weather-based timing at intersections requires accurate and timely detection of snowfall. This paper presents a snow detection algorithm that uses live video feed obtained from a video image vehicle detection system present at an intersection.

Stochastic Algorithm For Improved Operations At Isolated High Speed Intersections, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Department of Civil and Environmental Engineering: Faculty Publications

The current practice of specifying simultaneous gap out logic at isolated high speed signalized intersections places constraints on the signal controller logic that cannot be satisfied under high congestion level. Further, it often results in degraded signal efficiency and dilemma zone protection. A stochastic approach is proposed in this paper with the objective of increasing safety and efficiency at these intersections.

Towards Monitoring Galileo: The European Gnss Supervisory Authority In Statu Nascendi = Zur Künftigen Überwachungsagentur Des Galileo Systems, Vers Une Autorité De Surveillance Du Système Galileo, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

There is little doubt that one of the most interesting and revolutionary, but also complicated and challenging space projects of today is Galileo, Europe’s own full-fledged second-generation navigation satellite system. Developed jointly by the European Union through the Commission and the European Space Agency, Galileo should by the end of the decade have thirty operational satellites in middle-earth-orbits providing timing, positioning and navigation signals across the globe.

From the very beginning Galileo was envisaged in particular by the Commission as a public-private-partnership (PPP). On the one hand, a private concessionaire should operate the system as of full operational capability (originally …

Conduction-Band Electron Effective Mass In Zn0.87Mn0.13Se Measured By Terahertz And Far-Infrared Magnetooptic Ellipsometry, Tino Hofmann, U. Schade, K.C. Agarwal, B. Daniel, C. Klingshirn, M. Hetterich, C.M. Herzinger, Mathias Schubert

Nebraska Center for Materials and Nanoscience: Faculty Publications

We determine the electron effective mass parameter m^*=0.086±0.004 m₀ of thin-film n-type low-chlorine-doped Zn_0.87Mn_0.13Se with free-charge-carrier concentration N=4.5x10¹⁷ cm^-3 and optical mobility ) =300±20 cm² / (V s) using magneto-optic generalized ellipsometry in the terahertz and far-infrared spectral domain for wave numbers from ω =30–650 cm^-1. The room-temperature measurements were carried out with magnetic fields up to 3 T. We employ synchrotron and black-body radiation sources for the terahertz and far-infrared spectral regions, respectively. Comparison with previous experimental results from samples with considerably higher free electron …

Modeling Volume Changes In Porous Electrodes, Parthasarathy M. Gomadam, John W. Weidner

Faculty Publications

A three-dimensional mathematical model is presented to describe volume changes in porous electrodes occurring during operation. Material conservation equations are used to derive governing relationships between electrode dimensions and porosity for deposition/precipitation, intercalation, and ionomer-based electrodes. By introducing a parameter, called the swelling coefficient, the relative magnitudes of the change in electrode dimensions and the change in porosity are determined. The swelling coefficient is design-dependent and measured experimentally for a given cell design. The model is general and forms a critical addition required to extend the existing porous electrode models to include volume change effects. For the special case of …

Combinatorial Study Of Ni-Ti-Pt Ternary Metal Gate Electrodes On Hfo2 For The Advanced Gate Stack, K.-S. Chang, M. L. Green, J. Suehle, E. M. Vogel, H. Xiong, Jason R. Hattrick-Simpers, I. Takeuchi, O. Famodu, K. Ohmori, P. Ahmet, T. Chikyow, P. Majhi, B.-H. Lee, M. Gardner

Faculty Publications

The authors have fabricated combinatorial Ni–Ti–Pt ternary metal gate thin film libraries on HfO₂ using magnetron co-sputtering to investigate flatband voltage shift (ΔV_fb) , work function (Φ_m) , and leakage current density (J_L) variations. A more negative ΔV_fb is observed close to the Ti-rich corner than at the Ni- and Pt-rich corners, implying smaller Φ_m near the Ti-rich corners and higher Φ_m near the Ni- and Pt-rich corners. In addition, measured J_L values can be explained consistently with the observed Φ_m variations. Combinatorial methodologies prove to be useful …

An Experimental Investigation Of Guided Wave Propagation In Corrugated Plates Showing Stop Bands And Pass Bands, Tribikram Kundu, Sourav Banerjee, Kumar V. Jata

Faculty Publications

Nonplanar surfaces are often encountered in engineering structures. In aerospace structures, periodically corrugated boundaries are formed by friction-stir-welding. In civil engineering structures, rebars used in reinforced concrete beams and slabs have periodic surface. Periodic structures are also being used to create desired acoustic band gaps. For health monitoring of these structures, a good understanding of the elastic wave propagation through such periodic structures is necessary. Although a number of research papers on the wave propagation in periodic structures are available in the literature, no one experimentally investigated the guided wave propagation through plates with periodic boundaries and compared the experimental …

Elastic Wave Propagation In Sinusoidally Corrugated Waveguides, Sourav Banerjee, Tribikram Kundu

Faculty Publications

The ultrasonicwave propagation in sinusoidally corrugated waveguides is studied in this paper. Periodically corrugated waveguides are gaining popularity in the field of vibration control and for designing structures with desired acoustic band gaps. Currently only numerical method (Boundary Element Method or Finite Element Method) based packages (e.g., PZFlex) are in principle capable of modeling ultrasonic fields in complex structures with rapid change of curvatures at the interfaces and boundaries but no analyses have been reported. However, the packages are very CPU intensive; it requires a huge amount of computation memory and time for its execution. In this paper a new …

Thermo-Mechanical Characterization Of Copper Through-Wafer Interconnects, Peter A. Miranda, Amy J. Moll

Electrical and Computer Engineering Faculty Publications and Presentations

Copper through wafer interconnects (TWIs) have become a viable solution to providing interconnectivity between stacked die. In a world where minimizing chip real estate while increasing functionality is the goal for further miniaturization of electronics, TWIs hold a key role as new packaging schemes become critical for overall higher density. Little is known, however, about the impacts of mismatched coefficients of thermal expansion (CTEs) inherent to the materials used in their construction. CTE differences, if left unresolved, can pose reliability issues during TWI operation. This research focuses on providing insight into the stress levels experienced by TWI materials through finite …

A Mathematical Model For The Validation Of Safe Air-Blast Chilling Of Cooked Hams, L. J. Wang, A Amézquita, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

An integrated mathematical model of heat transfer and temperature-dependent bacterial growth was developed to validate the safety of cooked hams during air-blast chilling. Heat transfer through a cooked ham was mathematically modeled and analyzed with a finite element method. Response of bacteria to temperatures was quantitatively described using predictive microbiology. The cumulative effect of temperature history on the bacterial growth was taken into account in the model. For chilling cooked hams from 71°C to 10°C, the maximum error between the predicted and experimental core temperature was within 2.2°C, and the deviation between the predicted and measured total weight losses was …

Asymmetry Of Tidal Plume Fronts In An Eastern Boundary Current Regime, David A. Jay, Jiayi Pan, Philip M. Orton, Alexander R. Horner-Devine

Civil and Environmental Engineering Faculty Publications and Presentations

The Columbia River tidal plume or near-field is formed twice daily by the ebb outflow of the Columbia River. It is a part of a larger, anticyclonic plume bulge, which in turn is embedded in far-field plume and coastal waters. Because of the mixing caused directly and indirectly by plume fronts, the interaction of the tidal plume and bulge with the California Current upwelling regime plays a vital role in coastal productivity on the Oregon and Washington shelves. The tidal plume is initially supercritical with respect to the internal Froude number on all stronger ebbs. It is separated from the …

Hydrodynamics And Morphology In The Ems/Dollard Estuary: Review Of Models, Measurements, Scientific Literature, And The Effects Of Changing Conditions, Stefan A. Talke, Huib E. De Swart

Civil and Environmental Engineering Faculty Publications and Presentations

The Ems estuary has constantly changed over the past centuries both from man-made and natural influences. On the time scale of thousands of years, sea level rise has created the estuary and dynamically changed its boundaries. More recently, storm surges created the Dollard sub-basin in the 14th -15th centuries. Beginning in the 16th century, diking and reclamation of land has greatly altered the surface area of the Ems estuary, particularly in the Dollard. These natural and anthropogenic changes to the surface area of the Ems altered the flow patterns of water, the tidal characteristics, and the patterns of sediment deposition …

Maxwell-Wagner Relaxations And Their Contributions To The High Permittivity Of Calcium Copper Titanate Ceramics, Wei Li, Robert W. Schwartz

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Calcium copper titanate ceramics were fabricated by cold isostatic pressing at various calcination and sintering conditions. Depending on fabrication condition, three electrical responses were observed in the combined modulus and impedance plots, indicating the presence of two Maxwell-Wagner relaxations. These electrical responses show different response to temperature and applied field. The activation energies, as well as the driving force factors, were calculated for these relations. The determined activation energy values are in the range of 0.57 to 0.65 eV. The contribution of Maxwell-Wagner relaxations to the high permittivity of CCTO and related materials is briefly discussed.

Reducing Energy In Fpga Multipliers Through Glitch Reduction - Clock Power And Digit-Serial Addendum, Nathaniel Rollins, Michael J. Wirthlin

Faculty Publications

Sponsorship: NASA. In a previous paper it was shown that reducing the amount of glitches in digital designs can significantly reduce the amount of dynamic power consumption. Pipelined multipliers and a bit-serial multiplier design were used to show this. The paper failed to mention how much of the dynamic power consumption was due to the clock distribution. Also the only digit- serial multiplier digit size investigated was a digit size of 1. This paper addresses the issue of dynamic clocking power and includes results of digit-serial multipliers with larger digit sizes.

Techniques In The Design Of Thermomechanical Microactuators, Larry L. Howell, Timothy W. Mclain, Michael S. Baker, Christian D. Lott

Faculty Publications

The purpose of this chapter is to provide fundamental background for the design of thermomechanical microactuators. Actuation has been a particularly challenging aspect of microsystem development. Many actuation approaches used at the macro level, such as hydraulics, pneumatics, electric motors, internal combustion engines and turbines, are either too difficult to fabricate at the micro level or do not work well at that scale. Electrostatic attraction is one approach that has been widely used for actuation of microsystems; however, electrostatic actuators tend to have high voltage requirements and low output force capabilities. While electrostatic actuation is suitable for many applications, some …

Teaching Lean Manufacturing Concepts Using Physical Simulations Within Engineering Technology Program, Alok Verma

Engineering Technology Faculty Publications

Physical Simulations have a proven record as a teaching tool. Concepts that are often hard to grasp are made easy by the use of physical simulation activities. The constructivism learning theory suggests that people learn better by actively participating in the process of learning. Effectiveness of simulation-based learning is well recognized. According to the Encyclopedia of Educational Technology, "Simulation-based learning involves the placement of a student into a realistic scenario or situation. The student is then responsible for any changes that occur as a result of their decisions." The computer integrated manufacturing course in the mechanical engineering technology program was …

A Hybrid Course In Fundamentals Of Building Construction Using Combination Archived Video And Live Session Distance Learning, Vernon W. Lewis Jr., Carol L. Considine, June Ritchie

Engineering Technology Faculty Publications

A course in the Fundamentals of Building Construction has been a curricular requirement of the Civil Engineering Technology Program (CET) since its inception. This course was taught traditionally as an on-campus class. Over the last ten years, the CET program has expanded to contain an extensive distance learning component, with at least half of the enrollment located off campus. The model for the typical distance-learning class is to meet for three hours, once a week, with a fully interactive (voice) live class. In consideration of the demand of a growing distance learning system, it was decided to restructure this class …

A Comparison Between Frequent Out-Of-Class Assignments And Frequent In-Class Assessments Relative To Student Performance In A Sophomore Level Electrical Circuit Analysis Course, Isaac Flory, Christian Hearn

Engineering Technology Faculty Publications

Two parallel sections of a sophomore level circuit analysis course in Electrical Engineering Technology were structured to provide insight to the marginal utility of out-of-class assignments versus in-class assessments in academic performance. Student distributions for each section, the classroom model, the composition of the common tests and exam, and grading formats are discussed. The data presented and the conditions of the resulting observations indicate the model which favored out-of-class assignments led to improved test scores.