Bioresource and Agricultural Engineering Commons^™

Velocity Contour Weighting Method. I: Algorithm Development And Laboratory Testing, Daniel J. Howes, Brett F. Sanders

BioResource and Agricultural Engineering

An algorithm is developed for real-time estimation of the cross-sectional average velocity of a channel flow by using an upward-looking pulsed wave acoustic Doppler velocity meters (ADVM). The Velocity Contour Weighting Method (VCWM) is applicable to gradually varied flows in prismatic channels and requires little to no calibration. VCWM estimates the average velocity as a weighted average of ADVM bin velocities. Weights are based on the velocity distribution sampled by the ADVM. Collectively, the VCWM is able to adapt to a wide range of channel geometry and roughness features. Expressions for the velocity weights are developed by first applying a …

History Of The Biological Systems Engineering Program In Nebraska, University Of Nebraska-Lincoln, William E. Splinter

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Farm Machinery/Agricultural Engineering/Biological Systems Engineering program current and former faculty members at the University of Nebraska, as demonstrated here, has made a statewide, national, and worldwide impact on the efficient production of food. The quality of this recognition is evidenced best by peer professionals through recognized ASABE awards received by Nebraska alumni or professors. Since its inception in 1909 and until 2010, there have been 10 national presidents, 19 gold medal recipients and 33 named national award recipients. Currently there are 31 ASABE Fellows and two members of the National Academy of Engineering. This national recognition comes as a …

The Irrigation Sector Shift From Construction To Modernization: What Is Required For Success?, Charles M. Burt

BioResource and Agricultural Engineering

External pressures related to environmental protection, commodity prices, energy availability, larger populations, and climate change have combined to require an immediate and substantial improvement in agricultural irrigation performance. Worldwide progression towards modernized irrigation projects has been uneven and slower than desired, but decades of irrigation modernization development have clarified certain requirements for success, as well as illuminated indicators of project failure. Of particular importance are required shifts within the state and national irrigation bureaucracies, as well as universities.

High Ethanol Titers From Cellulose By Using Metabolically Engineered Thermophilic, Anaerobic Microbes, D. Aaron Argyros, Shital A. Tripathi, Trisha F. Barrett, Stephen R. Rogers, Lawrence F. Feinberg, Daniel G. Olson, Justin M. Foden, Bethany B. Miller, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

This work describes novel genetic tools for use in Clostridium thermocellum that allow creation of unmarked mutations while using a replicating plasmid. The strategy employed counter-selections developed from the native C. thermocellum hpt gene and the Thermoanaerobacterium saccharolyticum tdk gene and was used to delete the genes for both lactate dehydrogenase (Ldh) and phosphotransacetylase (Pta). The Δldh Δpta mutant was evolved for 2,000 h, resulting in a stable strain with 40:1 ethanol selectivity and a 4.2-fold increase in ethanol yield over the wild-type strain. Ethanol production from cellulose was investigated with an engineered coculture of organic acid-deficient engineered strains of …

Stage-Dependent Transient Storage Of Phosphorus In Alluvial Floodplains, Derek M. Heeren, Garey A. Fox, Ronald B. Miller, Daniel E. Storm, Amanda K. Fox, Chad J. Penn, Todd Halihan, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Models for contaminant transport in streams commonly idealize transient storage as a well-mixed but immobile system. These transient storage models capture rapid (near-stream) hyporheic storage and transport, but do not account for large-scale, stage-dependent interaction with the alluvial aquifer. The objective of this research was to document transient storage of phosphorus (P) in coarse gravel alluvium potentially influenced by large-scale, stage-dependent preferential flow pathways (PFPs). Long-term monitoring was performed at floodplain sites adjacent to the Barren Fork Creek and Honey Creek in northeastern Oklahoma. Based on results from subsurface electrical resistivity mapping which was correlated to hydraulic conductivity data, observation …

Bankfull Hydraulic Geometry Relationships For The Inner And Outer Bluegrass Regions Of Kentucky, Carmen Agouridis, Ruth Roseann Brockman, Stephen R. Workman, Lindell E. Ormsbee, Alex Fogle

Biosystems and Agricultural Engineering Faculty Publications

Bankfull hydraulic geometry relationships relate bankfull stream dimensions, such as cross-sectional area, width, mean depth, mean velocity, width to depth ratio, and slope to bankfull discharge. These relationships can assist in determining a design discharge for stream restoration and management projects. This study assessed 27 stable streams located in the Inner Bluegrass and Outer Bluegrass regions of Kentucky. Reaches were selected based on the presence of a U.S. Geological Survey gage, as well as other conditions such as presence of readily identifiable bankfull indicators, stability indices, and site accessibility. Bankfull channel dimensions and discharges were determined, and hydraulic geometry relationships …

Bioenergy Feedstock-Specific Enrichment Of Microbial Populations During High-Solids Thermophilic Deconstruction, Amitha P. Reddy, Martin Allgaier, Steven W. Singer, Terry C. Hazen, Blake A. Simmons, Philip Hugenholtz, Jean S. Vandergheynst

United States Department of Energy: Publications

Thermophilic microbial communities that are active in a high-solids environment offer great potential for the discovery of industrially relevant enzymes that efficiently deconstruct bioenergy feedstocks. In this study, finished green waste compost was used as an inoculum source to enrich microbial communities and associated enzymes that hydrolyze cellulose and hemicellulose during thermophilic high-solids fermentation of the bioenergy feedstocks switchgrass and corn stover. Methods involving the disruption of enzyme and plant cell wall polysaccharide interactions were developed to recover xylanase and endoglucanase activity from deconstructed solids. Xylanase and endoglucanase activity increased by more than a factor of 5, upon four successive …

Effects Of Sprinkler, Partial Sprinkler/Drip, And Drip Only Irrigation On Strawberry Transplants 2010-2011, Stuart Styles

BioResource and Agricultural Engineering

The purpose of the project is to develop an analysis of the current irrigation practices of the strawberry growers on the Central Coast of California. The primary research evaluation is during the establishment of transplants where sprinklers are typically used even though drip irrigation is available. Growers have been selected from Oxnard, Santa Maria, and Watsonville to provide a good cross section of the different strawberry growing areas.

The specific objectives of the project are to: (1) set up a research areas and control plots on a demonstration scale, (2) determine the key factors that affect the problems in early …

Design, Construction And Evaluation Of Seven Shank, Three Point Ripper, Daniel Degraaf

BioResource and Agricultural Engineering

This senior project discusses the design, construction, and testing of a seven shank, three point ripper built for de Graaf Ranch. This ripper will replace older equipment that was not built to withstand the horsepower developed by more modern tractors that are used by de Graaf Ranch. This tillage device is designed to meet ASABE standards for horsepower requirements of farm equipment. This implement incorporates a shear pin design that will protect the frame from damage in the event that the ripper encounters a subsoil obstacle that would significantly damage the equipment. The shank was designed to reduce the disturbance …

Extrusion And Alkali Extrusion Of Corn Stover To Improve Enzyme Saccharification, Shujing Zhang

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

Biomass pretreatment constitutes an important part in the whole process of bioethanol production. The main goals of pretreatment include improving cellulose accessibility to enzyme, enhancing sugar yields from hemicellulose, achieving low capital and energy costs, as well as low sugar degradation and low chemical requirements. Extrusion, as a continuous and high throughput pretreatment method, requires much less chemical compared to traditional alkali pretreatment. In this research, twin-screw extrusion was evaluated for its effect with regard to promoting sugar yields from corn stover. Also, the underlying factors contributing to this improvement were examined. It was found that extrusion with no chemicals …

Testing Fuel Efficiency Of Tractors With Both Continuously Variable And Standard Geared Transmissions, Christopher N. Howard, Michael F. Kocher, Roger M. Hoy, Erin E. Blankenship

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

A John Deere 8295R IVT tractor with a continuously variable transmission (CVT) and a John Deere 8295R PowerShift (PST) tractor (Waterloo, Iowa) with a standard geared transmission (GT) were tested for fuel consumption at three different travel speeds with six different load levels applied per speed. The JD 8295R PST tractor was tested both at full throttle (FT) and shifted up two gears and throttled back (SUTB) to achieve the same travel speed as at full throttle conditions. For each travel speed with each transmission mode, fuel consumption was determined to be linearly related to drawbar power. Linear regression results …

Streambank Erosion And Instability Induced By Groundwater Seepage, Taber L. Midgley, Garey A. Fox, Glenn V. Wilson, Derek M. Heeren, Andrew Simon, Eddy J. Langendoen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Excessive sediment is one of the most common surface water pollutants. It diminishes water quality and destroys aquatic habitat. Streambank erosion is known to be a major source of sediment in streams and rivers, contributing as much as 80% of the total sediment load in some watersheds. Little work has been done to study the effects of seepage on streambank erosion and failure. Prior research, primarily in the laboratory under well-defined and controlled conditions, has examined seepage as a mechanism for bank erosion, but more needs to be done to validate conclusions derived from the laboratory with field data. This …

Biofilter Media Characterization Using Water Sorption Isotherms, Guilherme Del Nero Maia, George B. Day, Richard S. Gates, Joseph L. Taraba

Biosystems and Agricultural Engineering Faculty Publications

Compost material has been used extensively as a gas‐phase biofilter media for contaminant gas treatment in recent years. One of the biggest challenges in the use of this type of material is adequate control of compost moisture content and understanding its effect on the biofiltration process. The present work provides a methodology for characterization of biofilter media under low moisture conditions. Results indicated that low levels of equilibrium moisture content (EMC) were obtained for high levels of equilibrium relative humidity (ERH), i.e., 99% ERH produced EMC of approximately 20% (dry basis) at 25° C. Most bacteria struggle to survive in …

Twin-Screw Extrusion Processing Of Distillers Dried Grains With Solubles (Ddgs)-Based Yellow Perch (Perca Flavescens) Feeds, Ferouz Y. Ayadi, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan, Michael L. Brown

Natural Resource Management Faculty Publications

Increases in global aquaculture production, compounded with limited availabilities of fish meal for fish feed, has created the need for alternative protein sources. Twinscrew extrusion studies were performed to investigate the production of nutritionally balanced feeds for juvenile yellow perch (Perca flavescens). Five isocaloric (~3.06 kcal/g) ingredient blends, adjusted to a target protein content of 36.7% db, were formulated with 0%, 10%, 20%, 30%, and 40% distillers dried grains with solubles (DDGS) at an initial moisture content of 5–7%db, with appropriate amounts of fish meal, fish oil, whole wheat flour, corn gluten meal, and vitamin and mineral premixes. …

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

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

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …

Transport Of Trace Elements In Runoff From Unamended And Pond‐Ash Amended Feedlot Surfaces, Jason R. Vogel, John E. Gilley, Gary L. Cottrell, Brian L. Woodbury, Elaine D. Berry, Roger Eigenberg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The use of pond ash (fly ash that has been placed in evaporative ponds for storage and subsequently dewatered) for feedlot surfaces provides a drier environment for livestock and furnishes economic benefits. However, pond ash is known to have high concentrations of trace elements, and the runoff water‐quality effects of feedlot surfaces amended with pond ash are not well defined. For this study, two experimental units (plots) were established in eight feedlot pens. Four of the pens contained unamended soil surfaces, and the remaining four pens had pond‐ash amended surfaces. Before each test, unconsolidated surface material was removed from four …

Drought Regionalization Of Brazos River Basin Using An Entropy Approach, Deepthi Rajsekhar, Ashok Mishra, Vijay P. Singh

2011 Symposium on Data-Driven Approaches to Droughts

Assessment and understanding of past climate is an important step for drought mitigation and water resources planning. In this study, stream flows imulation obtained from the variable infiltration capacity(VIC) model was used for drought characterization, and subsequently regionalization was done based on the annual severity level, for the Brazos basin in Texas over a time span of 1949-2000. It is important to study drought characteristics with in a regional context. Hence, identification of homogenous drought regions is a prerequisite, so that the drought characteristics can be studied with in each of these regions. In this study, the concept of entropy …

A Look At 20th Century Droughts, Vijay P. Singh, Ashok K. Mishra

2011 Symposium on Data-Driven Approaches to Droughts

Droughts exercise a profound effect on the social and economic fabric of nations. Many nations of the world experienced droughts encompassing the full spectrum of severity, areal extent and duration. The result has been that the economic development was hampered and many countries have not yet recouped fully from the ravages of droughts. The first decade of the 21st century has also witnessed varying degrees of droughts across the globe. Therefore, we ask the following questions: (a) Do droughts affect every part of the world? (b) Are there similarities in major droughts around the world? (c) Are climate change and …

Design And Cost Analysis Of A Citrus Orchard, Travis Cox

BioResource and Agricultural Engineering

No abstract provided.

Development Of A Testing Procedure Using Cone Index To Allow For Optimal Tire Performance, Ryan Pehle

BioResource and Agricultural Engineering

This project discusses the design, fabrication, and evaluation of a Soil Cone Penetrometer that is to be used to test tracks designated for modified tractor pulling. The penetrometer measures the force required to penetrate a soil and provides a recommended tire pressure specific for the conditions present at the point in time