Other Civil and Environmental Engineering Commons^™

Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increasing nitrogen use efficiency (NUE) in irrigated corn production is of great importance to overall agricultural sustainability. Studies have shown that crop canopy sensors can aid in this pursuit as they allow for the determination of nitrogen (N) requirements in split applications later in the growing season. Fertigation can also increase NUE as many split applications can be conducted. If crop canopy sensors could be used to direct N fertigation rates, overall NUE may be increased even further. However, in some cases, N differences may need to be determined later in the growing season after corn has tasseled, which can …

Spatial And Temporal Changes In Maize And Soybean Grain Yield, Precipitation Use Efficiency, And Crop Water Productivity In The U.S. Great Plains, Meetpal S. Kukal, S. Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Sustainable agricultural utilization of the limited water resources demands improvements in understanding the changes in crop water productivity (CWP) in space and time, which is often presented as a potential solution to relieve the growing pressure on fresh water resources. In addition, crop yield needs to be studied in relation to precipitation received annually and during the growing season for its contribution to reduce irrigation water requirements, which is quantified through precipitation use efficiency (PUE). Hence, systematic quantifications, mapping, and analyses of large-scale CWP and PUE levels are needed. This study aims to quantify long-term (1982-2013) information on grain yield, …

Large Co2 And Ch4 Emissions From Polygonal Tundra During Spring Thaw In Northern Alaska, Naama Raz-Yaseef, Margaret S. Torn, Yuxin Wu, David P. Billesbach, Anna K. Liljedahl, Timothy J. Kneafsey, Vladimir E. Romanovsky, David R. Cook, Stan D. Wullschleger

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The few prethaw observations of tundra carbon fluxes suggest that there may be large spring releases, but little is known about the scale and underlying mechanisms of this phenomenon. To address these questions, we combined ecosystem eddy flux measurements from two towers near Barrow, Alaska, with mechanistic soil-core thawing experiment. During a 2 week period prior to snowmelt in 2014, large fluxes were measured, reducing net summer uptake of CO₂ by 46% and adding 6% to cumulative CH₄ emissions. Emission pulses were linked to unique rain-on-snow events enhancing soil cracking. Controlled laboratory experiment revealed that as surface ice …

Air Injection As A Scour Countermeasure At Bridge Piers, Ravi Teja Reddy Tippireddy

Dissertations, Master's Theses and Master's Reports

Local scour is a major cause of concern for the stability of bridge piers and the safety of the public using the bridges. Structural countermeasures and flow-altering devices have been developed to deal with local scour. Many armoring structural countermeasures are very effective and efficient in clear water conditions but are susceptible to moving bed forms and leaching. The flow-altering devices are effective in both clear water conditions and moving bed forms, but are prone to clogging, less efficient in changing flow direction, etc. This study aims to reduce the local scour by injecting air in order to reduce the …

Lucidpipe™ Power System, Purdue Ect Team

ECT Fact Sheets Archive

In most gravity fed water transmission pipelines, it is desired to reduce excess pressure head to prevent undue strain on a pipeline and lower the incidence of leaks. Normally this is done with pressure reducing valves that essentially burn off this excess pressure as heat. The LucidPipe™ system converts it to low cost electricity thereby removing unwanted pressure and generating energy at the same time - energy that can be put used behind the grid or put back on the grid. The LucidPipe™ system extracts a small percentage of pressure head providing nearly invisible operation allowing water operators to fulfill …

Lap Splice Development Length Of Rebar In Stabilized Hollow Interlocking Compressed Earth Blocks, Thomas S. Bowdey

Master's Theses

This thesis investigates the tensile performance of unconfined lap splices in specimens constructed from interlocking compressed earth block (ICEB) units. All lap splice specimens were constructed from hollow ICEB half units with one side grouting channel. ICEB units used in this research were exclusively produced from the Soeng Thai Model BP6 block press. The BP6 block press is currently manufactured in Thailand under the guidance and direction of the Center of Vocational Building Technologies (CVBT). All ICEB units and grout constructed for this research were created from mix proportions of soil, sand, cement, and water. Rebar bar sizes were restricted …

Modeling Streambank Erosion On Composite Streambanks On A Watershed Scale, A. R. Mittelstet, D. E. Storm, G. A. Fox, P. M. Allen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Streambanks can be a significant source of sediment and phosphorus to aquatic ecosystems. Although the streambank-erosion routine in the Soil and Water Assessment Tool (SWAT) has improved in recent versions, the recently developed routine in SWAT 2012 has undergone limited testing, and the lack of site or watershed specific streambank data increases the uncertainty in the streambank-erosion predictions. There were two primary objectives of this research: (1) modify and test the 2012 SWAT streambank-erosion routine on composite streambanks, and (2) compare SWAT default and field-measured channel parameters and assess their influence on predicted streambank erosion. Three modifications were made to …

Field Emissions Of (Hydro)Chlorofluorocarbons And Methane From A California Landfill, Alexander H. Sohn

Master's Theses

A comprehensive field investigation was conducted at Potrero Hills Landfill (PHL) located in Suisun City, California to quantify emissions of twelve (hydro)chlorofluorocarbons (i.e. F-gases). The specific target constituents for this study included CFC-11, CFC-12, CFC-113, CFC-114, HCFC-21, HCFC-22, HCFC-141b, HCFC-142b, HCFC-151a, HFC-134a, HFC-152a, and HFC-245fa. The majority of the F-gas emission studies have been conducted outside of the United States and very limited field landfill emission data are available in the United States. Because of historical usage of blowing agents in insulation foams including CFC-11, HCFC-142b, HFC-134a, and HFC-245fa, models reported in literature predicted high F-gas emissions from a landfill …

Evaluating The Suitability Of Microbial Induced Calcite Precipitation Technique For Stabilizing Expansive Soils, Sikha Neupane

Boise State University Theses and Dissertations

Expansive soils, also known as swell-shrink soils have been a problem for civil infrastructures including roads and foundations from ancient times. The use of chemical additives such as cement and lime to stabilize expansive soils is a common practice among geotechnical engineers especially for lightly loaded structures. However, several occurrences of subgrade failures were observed after stabilizing with chemical additives hence engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is gaining attention as an environmental friendly soil improvement technique. Several researchers have successfully tested its feasibility in mitigating liquefaction induced problems in sandy soils. This …

Quantifying An Aquifer Nitrate Budget And Future Nitrate Discharge Using Field Data From Streambeds And Well Nests, Troy E. Gilmore, David P. Genereux, Kathleen M. Farrell, Helena Mitasova

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Novel groundwater sampling (age, flux, and nitrate) carried out beneath a streambed and in wells was used to estimate (1) the current rate of change of nitrate storage, dS_NO3 /dt, in a contaminated unconfined aquifer, and (2) future [NO₃^–]_FWM (the flow-weighted mean nitrate concentration in groundwater discharge) and f_NO3 (the nitrate flux from aquifer to stream). Estimates of dS_NO3 /dt suggested that at the time of sampling (2013) the nitrate storage in the aquifer was decreasing at an annual rate (mean = –9 mmol/m²yr) equal …

Fishing With Geographic Information Systems, James L. Freeman

Scholars Week

Title: Fishing With Geographic Information Systems (GIS)

Author: Lance Freeman

Mentor: Dr. Haluk Cetin

This study was conducted to utilize multiple geographic information systems (GIS) applications for specific parts of Kentucky Lake and Lake Barkley. Using Lowrance Insight Genesis, along with topographical maps to help utilize time on the water keeping fisherman in the areas they want to target for specific types of cover and structure to help catch what they are after. Most of this information had to come from typical seasonal patterns and research into a lakes history as to how it was made, along with what is …

Improved 2d And 3d Resistivity Surveys Using Buried Electrodes And Optimized Arrays: The Multi-Electrode Resistivity Implant Technique (Merit), Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

This thesis presents a novel resistivity method called Multi-Electrode resistivity technique (MERIT) that is used for high resolution imaging of complex geologic features at depth and near the edges of survey lines. The MERIT electrodes are especially shaped and designed to be self-driven using a robust-direct push technique. Measurements are taken using optimized arrays that are generated using a modified version of the “Compare-R” optimization algorithm. This work focused on both two-dimensional (MERIT2D) and three-dimensional (MERIT3D) applications of the buried array and show the relevance of the additional information gained by the addition of deep electrodes especially in sites with …

Effect Of Rainfall Timing And Tillage On The Transport Of Steroidhormones In Runoff From Manure Amended Row Crop Fields, Sagor Biswas, William L. Kranz, Charles A. Shapiro, Daniel D. Snow, Shannon L. Bartelt-Hunt, Mitiku Mamo, David D. Tarkalson, Tian C. Zhang, David P. Shelton, Simon J. Van Donk, Terry L. Mader

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Runoff generated from livestock manure amended row crop fields is one of the major pathways of hormone transport to the aquatic environment. The study determined the effects of manure handling, tillage methods, and rainfall timing on the occurrence and transport of steroid hormones in runoff from the row crop field. Stockpiled and composted manure from hormone treated and untreated animals were applied to test plots and subjected to two rainfall simulation events 30 days apart. During the two rainfall simulation events, detection of any steroid hormone or metabolites was identified in 8–86% of runoff samples from any tillage and manure …

Failure Mechanism Of Woven Roving Fabric/Vinyl Ester Composites In Freeze–Thaw Saline Environment, Elias Anis Toubia, Sadra Emami, Donald A. Klosterman

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

This experimental study investigates the degradation mechanisms of a glass fiber-reinforced plastic material commonly used in civil engineering applications. A substantial reduction in tensile, shear, and compression properties was observed after 100 days of freeze–thaw cycling in saline environment (-20°C to 20°C). Non-destructive inspection techniques were progressively conducted on unexposed (ambient condition) and exposed (conditioned) specimens. The dynamic mechanical analysis showed permanent decrease in storage modulus that was attributed to physical degradation of the polymer and/or fiber–matrix interface. This indicated the formation of internal cracks inside the exposed glass fiber-reinforced plastic laminate. The 3D X-ray tomography identified preferred damage sites …

How Acoustics In California High Performance Schools Relate To Student Achievement, Devin K. Wong

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This research project seeks to determine if students attending K–12 schools meeting a minimum standard of high performance classroom conditions in the state of California do evidence higher scholastic achievement, based on publically available results on state-wide standardized tests. In three phases, a subset of 200+ schools applying for grants dedicated to building high performance schools over the past decade was correlated with an existing database of achievement scores for all public schools in California. The criteria utilized to specify high performance classrooms was provided by the California High Performance Initiative (HPI) Grant program. Academic achievement was evaluated on a …

Wetlands And Coastal Systems: Protecting And Restoring Valuable Ecosystems, C. T. Agouridis, K. R. Douglas-Mankin, A. C. Linhoss, A. R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Wetlands and coastal systems are unique, highly productive, and often threatened landscapes that provide a host of services to both humans and the environment. This article introduces a five-article Wetlands and Coastal Systems Special Collection that evolved from a featured session at the 2015 ASABE Annual International Meeting in New Orleans, Louisiana. The Collection provides perspectives on tools and techniques for enhancing the protection and restoration of wetlands and coastal systems with emphasis on vegetation, hydrology, water quality, and planning. Topics span the Florida Everglades (two articles) and Virginia floodplain (one article) wetland systems and include remote sensing (one article) …

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 10 - Play 3 - 2016/06/15), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/2 - Play 3 - 2016/06/12), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1 - Play 2 - 2016/06/07), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.

University Of New Mexico Bioalgal Energy, Photosynthesis Rates Of Poplar Plants - Measurements With Tdl Machine (Enriched Co2 - Enriched-Exposed - Tray 1/3 - Play 1 - 2016/06/08), David Hanson

Energize New Mexico (NSF EPSCoR Track 1 IV)

Collect the photosynthetic rate of poplar plants under different isotopic compositions of CO2 with the TDL machine and with the Licor equipment.