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Full-Text Articles in Civil and Environmental Engineering

A Simple Method For Estimation Of Queue Length, S. P. Anusha, Lelitha Devi Vanajakshi, Anuj Sharma Dec 2013

A Simple Method For Estimation Of Queue Length, S. P. Anusha, Lelitha Devi Vanajakshi, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

Urban arterials are characterized by frequent intersections. Queue length and delay are the two primary measures of performance of intersection. These measures play a primary role in determining the arterial performance. This article presents a methodology to determine the number of vehicles in queue at a signalized intersection for under saturated traffic conditions. The results obtained were validated using actual values that are manually extracted. The root-mean-square error is of the range 1.3 vehicles for estimation of number of vehicles in queue. The various aspects that have to be considered in accurate estimation of performance measures are also discussed.


Elementary Implantable Force Sensor For Smart Orthopaedic Implants, Rebecca A. Wachs, David Ellstein, John Drazan, Colleen P. Healey, Richard L. Uhl, Kenneth A. Connor, Eric H. Ledet Dec 2013

Elementary Implantable Force Sensor For Smart Orthopaedic Implants, Rebecca A. Wachs, David Ellstein, John Drazan, Colleen P. Healey, Richard L. Uhl, Kenneth A. Connor, Eric H. Ledet

Department of Biological Systems Engineering: Papers and Publications

Implementing implantable sensors which are robust enough to maintain long term functionality inside the body remains a significant challenge. The ideal implantable sensing system is one which is simple and robust; free from batteries, telemetry, and complex electronics. We have developed an elementary implantable sensor for orthopaedic smart implants. The sensor requires no telemetry and no batteries to communicate wirelessly. It has no on-board signal conditioning electronics. The sensor itself has no electrical connections and thus does not require a hermetic package. The sensor is an elementary L-C resonator which can function as a simple force transducer by using a …


Passive Stormwater Samplers For Sampling Highway Runoff From Bmps: Feasibility Studies, Mitchell R. Klein Aug 2013

Passive Stormwater Samplers For Sampling Highway Runoff From Bmps: Feasibility Studies, Mitchell R. Klein

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Pollution from highway stormwater runoff has been an increasing area of concern within the environmental field. To respond to the need for reduced contamination within runoff many Best Management Practices (BMPs) have been implemented. One difficult aspect of BMPs is monitoring their effectiveness along with determining effluent concentrations. The current methods for stormwater sampling include sending technicians or installing an auto-sampler to collect either grab or composite samples. These methods become costly, cumbersome and infeasible due to the potentially large amount of BMPs across a region and the irregularity and difficulty of predicting storms. Passive samplers have proven themselves as …


Laboratory Evaluation Of A Turn Compensation Control System For A Ground Sprayer, W. M. Porter, J. A. Rascon, Yeyin Shi, Randal K. Taylor, Paul A. Weckler Jun 2013

Laboratory Evaluation Of A Turn Compensation Control System For A Ground Sprayer, W. M. Porter, J. A. Rascon, Yeyin Shi, Randal K. Taylor, Paul A. Weckler

Department of Biological Systems Engineering: Papers and Publications

The ability to compensate sprayer nozzle flow across a horizontal boom has the potential to mitigate the problem of inaccurate chemical application rate due to lateral speed differences when sprayers are turning. A laboratory testing platform and procedure were developed and tested with a commercial turn compensation control system for a ground sprayer. Virtual paths consisting of simulated GPS signals representing right and left turns separated by straight segments were simulated with four turning radii (75%, 125%, 250%, and 500%) based on boom width. Actual application rates from 11 nozzles spread across the boom were measured using load cells in …


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

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 …


Studying Platoon Dispersion Characteristics Under Heterogeneous Traffic In India, Jijo Mathew, Helen Thomas, Anuj Sharma, Lelitha Devi, Laurence Rilett Jan 2013

Studying Platoon Dispersion Characteristics Under Heterogeneous Traffic In India, Jijo Mathew, Helen Thomas, Anuj Sharma, Lelitha Devi, Laurence Rilett

Department of Civil and Environmental Engineering: Faculty Publications

Platoons are created by signalized intersections which control travel patterns of vehicles. It is common for platoons to disperse during normal traffic operations. While platoon dispersion has been studied extensively under homogenous and lane disciplined traffic conditions, this characteristic under heterogeneous conditions has not been addressed adequately. This study will be one of the first steps in this direction and will lead to better understanding and simulation of platoon dispersion under Indian conditions.

Data describing platoon dispersion was collected with video recording systems along an arterial in Chennai, India. The Robertson’s model parameters calibrated for this data was found to …


Maize Evapotranspiration, Yield Production Functions, Biomass, Grain Yield, Harvest Index, And Yield Response Factors Under Full And Limited Irrigation, Koffi Djaman, Suat Irmak, William R. Rathje, Derrel L. Martin, Dean E. Eisenhauer Jan 2013

Maize Evapotranspiration, Yield Production Functions, Biomass, Grain Yield, Harvest Index, And Yield Response Factors Under Full And Limited Irrigation, Koffi Djaman, Suat Irmak, William R. Rathje, Derrel L. Martin, Dean E. Eisenhauer

Department of Biological Systems Engineering: Papers and Publications

South-central Nebraska is one of the most extensively irrigated areas in the U.S., with over 65,000 active irrigation wells, and maize is the major agronomical crop produced. Maize production in this region requires supplementary irrigation for maximum productivity. Effective on-farm implementation of full and limited irrigation practices for potential improvements of crop productivity requires knowledge of locally developed crop yield response to water functions. In this study, the effects of full and limited irrigation practices on maize (Zea mays L.) plant height, leaf area index (LAI), grain yield and biomass production, actual crop evapotranspiration (ETa), yield production functions, …


Assessing Climate Change Impacts On Water Balance, Runoff, And Water Quality At The Field Scale For Four Locations In The Heartland, Michael W. Van Liew, Song Feng, T. B. Pathak Jan 2013

Assessing Climate Change Impacts On Water Balance, Runoff, And Water Quality At The Field Scale For Four Locations In The Heartland, Michael W. Van Liew, Song Feng, T. B. Pathak

Department of Biological Systems Engineering: Papers and Publications

This study employed the Soil and Water Assessment Tool (SWAT) to evaluate the impacts of projected future climate change scenarios on water balance, runoff, sediment, total nitrogen (N), and total phosphorus (P) at the field scale for four locations in the Heartland region: Sioux City (Iowa) and Columbus, Mullen, and Harrison (Nebraska). A conventional two-year corn-soybean rotation was assumed to be grown on each field. All fields were simulated identically in terms of topographic and cover/land management conditions. Model inputs for the fields differed in only

three ways: the forcing conditions for existing and future climatic scenarios (SRES A2, A1B, …


Use Of A Surrogate To Evaluate The Impact Of Tillage On The Transport Of Steroid Hormones From Manure-Amended Agricultural Fields, Sagor Biswas, William Kranz, Charles A. Shapiro, Mitiku Mamo, Shannon L. Bartelt-Hunt, Daniel D. Snow, David P. Shelton, David D. Tarkalson, Terry L. Mader, Simon J. Van Donk, Tian C. Zhang Jan 2013

Use Of A Surrogate To Evaluate The Impact Of Tillage On The Transport Of Steroid Hormones From Manure-Amended Agricultural Fields, Sagor Biswas, William Kranz, Charles A. Shapiro, Mitiku Mamo, Shannon L. Bartelt-Hunt, Daniel D. Snow, David P. Shelton, David D. Tarkalson, Terry L. Mader, Simon J. Van Donk, Tian C. Zhang

Department of Biological Systems Engineering: Papers and Publications

Beef feedlot manure distributed to row crop production areas is a potential surface water contaminant source of the steroid hormones commonly used in beef cattle production. This article reports on research conducted at the University of Nebraska Haskell Agricultural Laboratory near Concord, Nebraska, in July 2009. Manure, collected from beef feedlot pens, was stockpiled for ten months prior to application to a row crop field. Previous research identified that the detection frequency of steroid hormones in beef manure varies greatly. Thus, a surrogate (17α-ethynylestradiol, EE2) was applied at a rate of 75 g ha-1 to ensure detectable concentrations in …


Water Productivity Of Corn And Dry Bean Rotation On Very Fine Sandy Loam Soil In Western Nebraska, William E. Spurgeon, C. Dean Yonts Jan 2013

Water Productivity Of Corn And Dry Bean Rotation On Very Fine Sandy Loam Soil In Western Nebraska, William E. Spurgeon, C. Dean Yonts

Department of Biological Systems Engineering: Papers and Publications

Subsurface drip irrigation (SDI) was used to irrigate corn and dry beans in a crop rotation study for four years from 2005 to 2008 to evaluate the accumulative effect of irrigation amount on yield and irrigation water use efficiency (IWUE). This study was conducted on a very fine sandy loam soil using a short season corn hybrid typical for the area. Four irrigation treatments based on providing a fraction of the estimated crop evapotranspiration (ETc) were evaluated. The treatments were designed to replace a certain percentage of ETc and were denoted as I125, …


Development And Evaluation Of Ordinary Least Squares Regression Models For Predicting Irrigated And Rainfed Maize And Soybean Yields, Vivek Sharma, Daran R. Rudnick, Suat Irmak Jan 2013

Development And Evaluation Of Ordinary Least Squares Regression Models For Predicting Irrigated And Rainfed Maize And Soybean Yields, Vivek Sharma, Daran R. Rudnick, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

Understanding the relationships between climatic variables and soil physical and chemical properties with crop yields on large scales is critical for evaluating crop productivity to make better assessments of local and regional food security, policy, land and water resource allocation, and management decisions. In this study, ordinary least squares(OLS) regression models were developed to predict irrigated and rainfed maize and soybean yields at the county level as a

function of explanatory variables [precipitation (P), actual crop evapotranspiration (ETa), organic matter content (OMC), cation exchange capacity (CEC), clay content (CC), and available soil water capacity (ASW)] of the dominant soil type …


Transport Of Steroid Hormones In The Vadose Zone After Land Application Of Beef Cattle Manure, Simon Van Donk, Sagor Biswas, William L. Kranz, Daniel D. Snow, Shannon L. Bartelt-Hunt, Terry L. Mader, Charles A. Shapiro, David P. Shelton, David D. Tarkalson, Tian .. Zhang, Steve Ensley Jan 2013

Transport Of Steroid Hormones In The Vadose Zone After Land Application Of Beef Cattle Manure, Simon Van Donk, Sagor Biswas, William L. Kranz, Daniel D. Snow, Shannon L. Bartelt-Hunt, Terry L. Mader, Charles A. Shapiro, David P. Shelton, David D. Tarkalson, Tian .. Zhang, Steve Ensley

Department of Biological Systems Engineering: Papers and Publications

Few studies have been conducted to investigate the potential contamination of groundwater from manureborne steroid hormones. The objective of this study was to monitor leaching of steroid hormones at the bottom of 2.4 m deep percolation lysimeters installed in plots treated with beef cattle manure. Soil samples were also collected from surrounding field plots. Treatments consisted of application of manure from two treatment methods (stockpiling and composting) or no manure application. Laboratory analyses of manure, soil, and leachate samples used liquid chromatography and tandem mass spectrometry to identify 17 steroid hormones and metabolites. Progesterone, estrone, β-zearalenol, and 4-androstenedione were detected …


Implementation Of A ”Rapid Design Challenge” In A Cross-Disciplinary Senior Capstone Course And Evaluation Of Device Performance, Abby M. Kelly, Austin Lammers, David D. Jones, Richard Stowell, Roger Hoy, Evan Curtis, Angela K. Pannier Jan 2013

Implementation Of A ”Rapid Design Challenge” In A Cross-Disciplinary Senior Capstone Course And Evaluation Of Device Performance, Abby M. Kelly, Austin Lammers, David D. Jones, Richard Stowell, Roger Hoy, Evan Curtis, Angela K. Pannier

Department of Biological Systems Engineering: Papers and Publications

The senior capstone experience within the Department of Biological Systems Engineering at the University of Nebraska-Lincoln is a two-semester, two-course sequence intended to give senior students realistic design experience, working with real projects, real clients, faculty consultants, and teammates to produce a deliverable that meets the client’s needs. Students within this course sequence come from two different degree programs (agricultural engineering and biological systems engineering) and within each degree program from a variety of “emphasis areas”, e.g. biomedical engineering, environmental engineering, machine design. While the goal of this course is for students to experience a “real” design project, we felt …


Variability Of Extreme Precipitation In Coastal River Basins Of The Southern Mexican Pacific Region, Nancy Perez-Morga, Thomas Kretzschmar, Tereza Cavazos, Stephen V. Smith, Francisco Munoz-Arriola Jan 2013

Variability Of Extreme Precipitation In Coastal River Basins Of The Southern Mexican Pacific Region, Nancy Perez-Morga, Thomas Kretzschmar, Tereza Cavazos, Stephen V. Smith, Francisco Munoz-Arriola

Department of Biological Systems Engineering: Papers and Publications

Extreme wet and dry years (± 1 standard deviation, respectively), as well as the top 95 percentile (P95) of daily precipitation events, derived from tropical cyclone (TC) and nontropical cyclone (NTC) rainfall, were analyzed in coastal river basins in Southern Oaxaca, Mexico (Río Verde, Río Tehuantepec, and the Southern Coast). The study is based on daily precipitation records from 47 quality-controlled stations for the 1961 to 1990 period and TC data for the Eastern Tropical Pacific (EPAC). The aim of this study was to evaluate extreme (dry and wet) trends in the annual contribution of daily P95 precipitation events and …


Acetyl-Coa Carboxylases Are Checkpoints In Adipocyte Differentiation, Elizabeth Lyn Cordonier, Daniel Camara Teixeira, Zhonghi Han, Angela K. Pannier, Janos Zempleni Jan 2013

Acetyl-Coa Carboxylases Are Checkpoints In Adipocyte Differentiation, Elizabeth Lyn Cordonier, Daniel Camara Teixeira, Zhonghi Han, Angela K. Pannier, Janos Zempleni

Department of Biological Systems Engineering: Papers and Publications

No abstract provided.


Network Analysis Of Endogenous Gene Expression Profiles After Polyethyleneimine-Mediated Dna Delivery, Timothy M. Martin, Sarah A. Plautz, Angela K. Pannier Jan 2013

Network Analysis Of Endogenous Gene Expression Profiles After Polyethyleneimine-Mediated Dna Delivery, Timothy M. Martin, Sarah A. Plautz, Angela K. Pannier

Department of Biological Systems Engineering: Papers and Publications

Background—DNA delivery systems, which transport exogenous DNA to cells, have applications that include gene therapy, tissue engineering and medical devices. Although the cationic nonviral DNA carrier polyethyleneimine (PEI) has been widely studied, the molecular factors and pathways underlying PEI-mediated DNA transfer remain largely unknown, preventing the design of more efficient delivery systems.

Methods—HEK 293 T cells were treated with polyplexes formed with PEI and pEGFPLuc encoding for green fluorescent protein (GFP). Transfected cells expressing GFP were flowseparated from treated, untransfected cells. Gene expression profiles were obtained using Affymetrix HG-U133 2.0 microarrays and differentially expressed genes were identified using R/ Bioconductor. …


Runoff Nutrient Transport As Affected By Land Application Method, Swine Growth Stage, And Runoff Rate, J. E. Gilley, Shannon L. Bartelt-Hunt, S. J. Lamb, X. Li, D. B. Marx, D. D. Snow, D. B. Parker, B. L. Woodbury Jan 2013

Runoff Nutrient Transport As Affected By Land Application Method, Swine Growth Stage, And Runoff Rate, J. E. Gilley, Shannon L. Bartelt-Hunt, S. J. Lamb, X. Li, D. B. Marx, D. D. Snow, D. B. Parker, B. L. Woodbury

Department of Biological Systems Engineering: Papers and Publications

This study was conducted to measure the effects of slurry application method, swine growth stage, and flow rate on runoff nutrient transport. Swine slurry was obtained from production units containing grower pigs, finisher pigs, or sows and gilts. The swine slurry was applied using broadcast, disk, or injection methods at a rate required to meet annual nitrogen requirements for corn. Three 30 min simulated rainfall events, separated by 24 h intervals, were applied to the experimental plots at an intensity of 70 mm h-1. Inflow was applied at the top of each plot in four successive increments after …


Hourly And Daily Single And Basal Evapotranspiration Crop Coefficients As A Function Of Growing Degree Days, Days After Emergence, Leaf Area Index, Fractional Green Canopy Cover, And Plant Phenology For Soybean, Suat Irmak, Lameck O. Odhiambo, James Specht, Koffi Djaman Jan 2013

Hourly And Daily Single And Basal Evapotranspiration Crop Coefficients As A Function Of Growing Degree Days, Days After Emergence, Leaf Area Index, Fractional Green Canopy Cover, And Plant Phenology For Soybean, Suat Irmak, Lameck O. Odhiambo, James Specht, Koffi Djaman

Department of Biological Systems Engineering: Papers and Publications

Hourly evapotranspiration (ET) crop coefficients (Kc) are needed to optimize the effectiveness and efficiency of high-frequency micro- and sprinkler irrigation practices involving the application of water multiple times a day. However, not much is known about the daily and seasonal patterns and magnitudes in hourly Kc values for soybean. In addition, locally developed Kc values are necessary for more robust within-season irrigation management, crop ET estimation, and water balance analyses. Hourly and daily Kc functions were developed for soybean in south-central Nebraska through extensive field research. Actual crop evapotranspiration (ETa) was measured using a …


Use Of A Surrogate To Evaluate The Impact Of Tillage On The Transport Of Steroid Hormones From Manure-Amended Agricultural Fields, Sagor Biswas, William L. Kranz, Charles A. Shapiro, Mitiku Mamo, Shannon L. Bartelt-Hunt, Daniel D. Snow, David P. Shelton, David D. Tarkalson, Terry L. Mader, Simon J. Van Donk, Tian C. Zhang Jan 2013

Use Of A Surrogate To Evaluate The Impact Of Tillage On The Transport Of Steroid Hormones From Manure-Amended Agricultural Fields, Sagor Biswas, William L. Kranz, Charles A. Shapiro, Mitiku Mamo, Shannon L. Bartelt-Hunt, Daniel D. Snow, David P. Shelton, David D. Tarkalson, Terry L. Mader, Simon J. Van Donk, Tian C. Zhang

Department of Biological Systems Engineering: Papers and Publications

Beef feedlot manure distributed to row crop production areas is a potential surface water contaminant source of the steroid hormones commonly used in beef cattle production. This article reports on research conducted at the University of Nebraska Haskell Agricultural Laboratory near Concord, Nebraska, in July 2009. Manure, collected from beef feedlot pens, was stockpiled for ten months prior to application to a row crop field. Previous research identified that the detection frequency of steroid hormones in beef manure varies greatly. Thus, a surrogate (17α-ethynylestradiol, EE2) was applied at a rate of 75 g ha-1 to ensure detectable concentrations in …


Transferability Of Jarvis-Type Models Developed And Re-Parameterized For Maize To Estimate Stomatal Resistance Of Soybean: Analyses On Model Calibration, Validation, Performance, Sensitivity, And Elasticity, Denis Mutiibwa, Suat Irmak Jan 2013

Transferability Of Jarvis-Type Models Developed And Re-Parameterized For Maize To Estimate Stomatal Resistance Of Soybean: Analyses On Model Calibration, Validation, Performance, Sensitivity, And Elasticity, Denis Mutiibwa, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

In a previous study by the same authors, a new modified Jarvis model (NMJ-model) was developed, calibrated, and validated to estimate stomatal resistance (rs) for maize canopy on an hourly time step. The NMJ-model’s unique subfunctions, different from the original Jarvis model (J-model), include a photosynthetic photon flux density

(PPFD)-rs response subfunction developed from field measurements and a new physical term, Aexp(1/LAI), where A is the minimum stomatal resistance and LAI is the green leaf area index, to account for the influence of canopy development on rs, especially during partial canopy stage in the early season and …


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 Jan 2013

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 Biological Systems Engineering: Papers and Publications

Quantifying actual evapotranspiration (ETa) 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 ETa, sensible heat flux (H), net radiation (Rn), soil heat flux (G), meteorological variables (air temperature, Ta; incoming shortwave radiation, Rs; 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 …


Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak Jan 2013

Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

With uncertainty in future irrigation water availability and regulations on nutrient application amounts, experimentally determined effects of “controllable” management strategies such as nitrogen (N), water, and their combination on crop water productivity (CWP, also known as crop water use efficiency) and actual evapotranspiration (ETa) are essential. The effects of various N application rates (0, 84, 140, 196, and 252 kg ha-1) under fully irrigated (FIT), limited irrigation (75% FIT), and rainfed conditions on maize (Zea mays L.) yield and various CWP indices were investigated in 2011 and 2012 growing seasons under linear-move sprinkler irrigation in south …


Avhrr-Ndvi-Based Crop Coefficients For Analyzing Long-Term Trends In Evapotranspiration In Relation To Changing Climate In The U.S. High Plains, Denis Mutiibwa, Suat Irmak Jan 2013

Avhrr-Ndvi-Based Crop Coefficients For Analyzing Long-Term Trends In Evapotranspiration In Relation To Changing Climate In The U.S. High Plains, Denis Mutiibwa, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

Studies in regions of extensive irrigation practices have revealed a significant influence of evaporative cooling on regional temperatures as a result of surface energy redistribution during evaporation. In the U.S. High Plains, maximum temperatures during the last quarter of the 20th century have been decreasing. We investigated the trends in evapotranspiration (ET or latent heat) fluxes originating from increasing irrigation practices in the High Plains region from 1981 to 2008. We estimated actual ET (ETc) over the entire High Plains from the spatial crop coefficients (Kc) and spatial reference (potential) ET (ETref). We proposed …