Civil and Environmental Engineering Commons^™

Role Of Information On Probability Of Traffic Conflict On The Onset Of Yellow, Nathaniel P. Burnett, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

This paper examines the effect of information provided to drivers through advance warning flashers (AWFs) on driver’s probability of conflict at the onset of yellow at a high-speed intersection. AWFs are specifically designed to minimize the number of vehicles trapped in their respective dilemma zones at the onset of yellow. A probit modeling technique was used to establish dilemma zone boundaries. Based on the dilemma zone boundaries probability of a perceived conflict curves was computed and compared against actual conflicts observed at each of the studied intersections. The comparison between the actual and theoretical probability of conflict curves generated a …

Cellular Arrays For Large-Scale Analysis Of Transcription Factor Activity, Abigail D. Bellis, Beatriz Peňalver-Bernabé, Michael S. Weiss, Michael E. Yarrington, Maria V. Barbolina, Angela K. Pannier, Jacqueline S. Jeruss, Linda J. Broadbelt, Lonnie D. Shea

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Identifying molecular mechanisms or therapeutic targets is typically based on large-scale cellular analysis that measures the abundance of mRNA or protein; however, abundance does not necessarily correlate with activity. We report a method for direct large-scale quantification of active pathways that employs a cellular array with parallel gene delivery of constructs that report pathway activity. The reporter constructs encode luciferase, whose expression is influenced by binding of transcription factors (TFs), which are the downstream targets of signaling pathways. Luciferase levels are quantified by bioluminescence imaging (BLI), which allows for rapid, noninvasive measurements. Activity profiles by BLI of 32 TFs were …

Microarray Analysis Of Gene Expression Profiles In Cells Transfected With Nonviral Vectors, Sarah A. Plautz, Gina Boanca, Jean-Jack M. Riethoven, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Inefficient gene delivery is a critical factor limiting the use of nonviral methods in therapeutic applications including gene therapy and tissue engineering. There have been few efforts to understand or engineer the molecular signaling pathways that dictate the efficacy of gene transfer. Microarray analysis was used to determine endogenous gene expression profiles modulated during nonviral gene transfer. Nonviral DNA lipoplexes were delivered to HEK 293T cells. Flow cytometry was used to isolate a population of transfected cells. Expression patterns were compared between transfected and nontransfected samples, which revealed three genes that were significantly upregulated in transfected cells, including RAP1A, …

Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang

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

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures were collected at the time of paving and were transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of the …

An Exploratory Survey Of Drivers’ Knowledge Of Right Of Way At Freeway On-Ramp Merging Areas, Deogratias Eustace, Stephen Owusu-Ansah, Vamsi Krishna Indupuru

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Motor vehicle crashes are one of the leading causes of death in the United States. The most recent data available show that in 2006 there were almost 6 million police-reported motor vehicle crashes in the United States where a total of 42,642 people were killed and an additional 2.6 million were injured. The majority of these motor vehicle crashes occurred at intersections or within the intersection influence areas. Traffic conflicts occur at intersections due to traffic streams moving in different directions interfering with each other, and as a result they become areas with high potential for traffic crashes compared with …

Improving Surveying Accuracy And Efficiency In Connecticut: An Accuracy Assessment Of Geoid03 And Geoid09, Thomas H. Meyer, Robert Baron

Department of Natural Resources and the Environment Articles

Comparing published NAVD 88 Helmert orthometric heights of First-Order bench marks against GPS-determined orthometric heights showed that GEOID03 and GEOID09 perform at their reported accuracy in Connecticut. GPS-determined orthometric heights were determined by subtracting geoid undulations from ellipsoid heights obtained from a network least-squares adjustment of GPS occupations in 2007 and 2008. A total of 73 markers were occupied in these stability classes: 25 class A, 11 class B, 12 class C, 2 class D bench marks, and 23 temporary marks with transferred elevations. Adjusted ellipsoid heights were compared against OPUS as a check. We found that: the GPS-determined orthometric …

Optimization And Economic Evaluation Of Industrial Gas Production And Combined Heat And Power Generation From Gasification Of Corn Stover And Distillers Grains, Ajay Kumar, Yaşar Demirel, David D. Jones, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2,000 kg/h. Aspen Plusbased model for gasification was combined with a CHP generation model, and optimized using corn stover and dried distillers grains with solubles (DDGS) as the biomass feedstocks. The cold gas efficiencies for gas production were 57% and 52%, respectively, for corn stover and DDGS. The selling …

Analyzing The Effects Of Led Traffic Signals On Urban Intersection Safety, Deogratias Eustace, Valerie E. Griffin, Peter W. Hovey

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

In 2002, there were 1,299,000 crashes at signalized intersections in the United States. These crashes account for approximately 21 percent of total crashes and about 24 percent of all fatal and injury collisions. The social and financial impact of this number of collisions is substantial. The Federal Highway Administration (FHWA) and other agencies have recognized the detrimental effects of intersection crashes on our society and continue to fund research that will lead to a decrease in crash frequency. Numerous countermeasures have been tested for their potential to reduce crashes. Infrastructure improvements such as the construction of left-turn lanes, the removal …

The Impacts Of Emergency Vehicle Signal Preemption On Urban Traffic Speed, Hualiang (Harry) Teng, Valerian Kwigizile, Gang Xie, Mohamed S. Kaseko, A. Reed Gibby

Civil and Environmental Engineering and Construction Faculty Research

We used GPS data from paratransit vehicles to evaluate the impact of emergency vehicles on urban traffic speeds. The results indicate that speed variance is significantly higher during emergency preemption and the mean speeds of traffic flowing in the same direction as the emergency vehicle and on crossing streets are lower during preemption than during normal conditions. Regression results indicate that traffic on major arterials and traffic in the opposite direction of the emergency vehicle tend to have higher speed during signal preemption. Signal preemption during peak periods and duration of preemption had a significant negative impact on traffic speeds. …

Performance Of A Stormwater Filter And Bacteria Inactivation Using Biocidal Media, Alexander Scott Bowerman

Master's Theses

There are many possible ways to mitigate stormwater pollution, but this study focused on the DrainPacTM catchment basin insert and the feasibility of integrating N-halamine biocidal brominated beads into the filter system. This study was divided into three sections. The first section involved testing a DrainPacTM filter for treatable flow rates, head loss, and removal of solids, oil, and bacteria. The DrainPacTM filter is designed to be installed in a stormwater catch basin. The filter is composed of a 12 x 41 inch metal frame with textile filter media attached to it in a basket shape. The upper portion of …

City Of Davis Greenbelt Master Plan, Brandon Haydu

Master's Theses

The City of Davis is currently updating its Parks and Recreation Facilities Master Plan. During the update, greenbelts were identified as a highly used and desired facility. This Greenbelt Master Plan serves as a plan focused on the opportunities greenbelts can provide as recreational and transportation facilities. This report has analyzed community feedback, greenbelt coverage, greenbelt capacity, and existing local, state, and federal design guidelines. The final plan is a set of goals, objectives, policies, and programs, along with a greenbelt map, which is aimed at improving the greenbelt infrastructure in Davis through the year 2020.

Nebraska Water And Energy Flux Measurement, Modeling, And Research Network (Nebflux), Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Surface energy and water vapor fluxes play a critical role in understanding the response of agro‐ecosystems to changes in environmental and atmospheric parameters. These fluxes play a crucial role in exploring the dynamics of water and energy use efficiencies of these systems. Quantification of the fluxes is also necessary for assessing the impact of land use and management changes on water balances. Accomplishing these goals requires measurement of water vapor and energy exchanges between various vegetation surfaces and microclimates for long‐enough periods to understand the behavior and dynamics involved with the flux transfer so that robust models can be developed …

Numerically Predicting Seepage Gradient Forces And Erosion: Sensitivity To Soil Hydraulic Properties, Garey A. Fox, Derek M. Heeren, Glenn V. Wilson, E. J. Langendoen, Amanda K. Fox, Maria L. Chu-Agor

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Research has suggested that streambank seepage can be an important mechanism of bank instability; however, limited information is available on the level of soil characterization necessary to accurately predict seepage gradient forces and erosion. The objective of this research was to quantify the expected range of predicted seepage gradients for various degrees of site characterization. Uncertainty analysis on seepage gradient predictions was performed relative to variability in soil hydraulic properties. A two-dimensional unsaturated/saturated groundwater flow model was used to simulate a homogeneous soil layer for sand and loamy sand soils packed at various bulk densities, ρ_b. A pedotransfer …

On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The 1‐D and single layer combination‐based energy balance Penman‐Monteith (PM) model has limitations in practical application due to the lack of canopy resistance (r_c) data for different vegetation surfaces. r_c could be estimated by inversion of the PM model if the actual evapotranspiration (E_Ta) rate is known, but this approach has its own set of issues. Instead, an empirical method of estimating r_c is suggested in this study. We investigated the relationships between primary micrometeorological parameters and rc and developed seven models to estimate r_c for a nonstressed maize canopy on an hourly …

161. The Potential Role Of Extensor Muscle Fatigue In The Onset Of Intervertebral Disc Degeneration: A Novel In Vivo Model, Mary Beth M. Grabowsky, Nicholas A. Pallota, Matthew W. Connelly, Brett Van Etten, Rebecca A. Wachs, Max Alley, Joseph C. Glennon, Andrew H. Dubin, John W. German, Richard L. Uhl, Eric H. Ledet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

BACKGROUND CONTEXT: Occupation is strongly correlated to low back pain (LBP). Specific occupational activities associated with low back pain include poor posture, whole body vibration, and repetitive lifting. These activities have a common link: they result in fatigue of the primary spinal extensor musculature. This fatigue may lead to increased intervertebral loading - a stimulus for disc degeneration. If true, this association could provide a vital connection between detrimental physical activities and LBP. However, the link between muscle fatigue and increased load across the disc space has never been quantified in vivo.

PURPOSE: The purpose of this study was to …

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, …

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, …

The International Charter And Flood Mapping, Jie Shan

GIS Day

An overview of recent Purdue activities related to the International Charter for Space and Major Disasters, including general information about The Charter, 3 Indiana flood examples, and a summary of the lessons learned therefrom.

Nutrient And Bacterial Transport In Runoff From Soil And Pond Ash Amended Feedlot Surfaces, John E. Gilley, Jason R. Vogel, Elaine D. Berry, Roger Eigenberg, David B. Marx, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The addition of pond ash (fly ash that has been placed in evaporative ponds and subsequently dewatered) to feedlot surfaces provides a healthier environment for livestock and economic advantages for the feedlot operator. However, the water quality effects of pond ash amended surfaces are not well understood. The objectives of this field investigation were to: (1) compare feedlot soil properties, and nutrient and bacterial transport in runoff, from pond ash amended surfaces and soil surfaces; (2) compare the effects of unconsolidated surface materials (USM) (loose manure pack) and consolidated subsurface materials (CSM) (compacted manure and underlying layers) on nutrient and …

Investigation Of The Geotechnical Properties Of Municipal Solid Waste As A Function Of Placement Conditions, Wilson W. Wong

Master's Theses

An investigation of the variability of engineering properties of municipal solid waste as a function of placement conditions was conducted. Limited data have been reported for the engineering properties of municipal solid waste (MSW) as a function of placement conditions. Wastes have high variability of engineering properties due to heterogeneity in composition and component size; influence from time based effects; and presence of compressible solids. Control of moisture content of MSW at the time of waste placement provides opportunity for increased capacity at a given landfill site due to higher compacted unit weight as well as for control of other …

Embodied Energy Analysis: A Sustainable Construction Design Assessment Tool, Adolf Acquaye, Aidan Duffy, Biswajit Basu

Conference Papers

Embodied energy analysis can be used as a construction design assessment tool in a sustainable matrix for a building. Its implementation however remains challenging mainly because of data measurement errors. A comparison between the deterministic embodied energy (EE) of a building and the stochastic EE of the same building undertaken using Monte Carlo simulation showed a wide variation in results. It is recommended that the specification of EE intensity of building materials in the construction industry can assist in producing accurate and more credible EE values of building.

Preserving Assets In At-Risk Municipalities: Financial Strategies For Climate Change Adaptation, New England Environmental Finance Center

Climate Change

A large share of America's population, businesses and economic activity now occurs in coastal areas. At the same time, during this century many coastal communities are likely to be severely impacted by sea level rise and increased storm surge and tidal flooding.

“What to do” about this vulnerability is the subject of this brief. It is intended to help municipalities identify courses of action and steps they might take toward increasing their resilience, especially regarding financial resources that will need to be allocated toward the various strategies identified.

Impact Of Microclimatic Data Measured Above Maize And Grass Canopies On Penman‐Monteith Reference Evapotranspiration Calculations, Suat Irmak, Lameck O. Odhiambo

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimation of reference evapotranspiration (ET_ref) using measured microclimatic data and the Penman‐Monteith (PM) method provides a powerful means of quantifying actual plant evapotranspiration (ET_a) needed for use in various disciplines. When applying the PM method to estimate ET_ref, it is desirable to measure the required microclimatic data over a reference grass or alfalfa surface rather than above non‐reference surfaces. However, in reality, establishing and maintaining a reference surface for long periods of time is a difficult task. Other surface energy balance systems, such as the Bowen ratio energy balance system (BREBS), eddy covariance system, …

Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability for irrigation throughout the world has been reduced in recent years due to a combination of frequent droughts and competition for water resources among agricultural, industrial, and urban users. In addition, some major agricultural areas face moderate to significant reductions of rainfall, or changes in timing of stream flow due to changes in timing of snowmelt, as a result of global climate change. Under such conditions, sophisticated irrigation water management will be required to optimize water use efficiency and maintain sufficient levels of crop productivity and quality. A key factor to achieve these targets is the estimation of …

Magnitude And Trends Of Reference Evapotranspiration Rates In South Central Nebraska: Daily, Monthly, Growing Season Total, And Annual Total, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Reference evapotranspiration (ET_ref ) is used to determine the actual water use (ET_a) rate for various crops and is one of the key variables that needs to be determined accurately for effective irrigation management. This extension circular provides information on the magnitude and temporal distribution of daily, monthly, annual, and growing season alfalfa-reference evapotranspiration (ET_ref)) in south central Nebraska. It also discusses why long-term average ET_ref values may not represent non-average years or be accurate enough for irrigation management.

The most common way to calculate actual crop water use (ET_a) for a …

Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh Pitla, L. G. Wells, S. A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The soil coulterometer is an “on‐the‐go” electro‐mechanical system which collects impedance force data at multiple depths using an oscillating coulter. During the initial testing (summer 2006), only vertical soil impedance force data was collected using a pressure sensor. To improve the performance of the coulterometer, an extended octagonal ring transducer was integrated into the system to collect both the horizontal and vertical impedance forces given by the soil. In the summer of 2007, data was collected using the revised sensor from a typical central Kentucky field setting in a 0.8‐ha (2‐acre) plot. Four passes were made with the coulterometer. Seventy …

Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Paul J. Jasa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Leaving crop residue on the soil surface is one of the easiest and most cost-effective methods of reducing soil erosion. Research in Nebraska and other midwestern states has shown that leaving as little as 20 percent of the soil surface covered with crop residue can reduce soil erosion by one-half of what it would be from residue-free conditions. Greater amounts of residue cover will further reduce erosion. Many Conservation Plans specify crop residue management or residue left on the soil surface as the primary erosion control method. Generally, the amount of cover required after planting ranges from 30 percent to …

Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability for irrigation throughout the world has been reduced in recent years due to a combination of frequent droughts and competition for water resources among agricultural, industrial, and urban users. In addition, some major agricultural areas face moderate to significant reductions of rainfall, or changes in timing of stream flow due to changes in timing of snowmelt, as a result of global climate change. Under such conditions, sophisticated irrigation water management will be required to optimize water use efficiency and maintain sufficient levels of crop productivity and quality. A key factor to achieve these targets is the estimation of …

Regional Co2 And Latent Heat Surface Fluxes In The Southern Great Plains: Measurements, Modeling, And Scaling, W. J. Riley, Sebastien C. Biraud, Margaret S. Torn, Marc L. Fischer, David P. Billesbach, Joe A. Berry

Department of Agricultural and Biological Systems Engineering: Faculty Publications

[1] Characterizing net ecosystem exchanges (NEE) of CO2 and sensible and latent heat fluxes in heterogeneous landscapes is difficult, yet critical given expected changes in climate and land use. We report here a measurement and modeling study designed to improve our understanding of surface to atmosphere gas exchanges under very heterogeneous land cover in the mostly agricultural U.S. Southern Great Plains (SGP). We combined three years of site-level, eddy covariance measurements in several of the dominant land cover types with regional-scale climate data from the distributed Mesonet stations and Next Generation Weather Radar precipitation measurements to calibrate a land surface …

Interpreting Surface-Wave Data For A Site With Shallow Bedrock, Daniel W. Casto, Barbara Luke, Carlos Calderon-Macias, Ronald Kaufmann

Civil and Environmental Engineering and Construction Faculty Research

The inversion of dispersive Rayleigh-wave data has been shown to be successful in providing reliable estimated shear-wave velocities within unconsolidated materials in the near surface. However, in a case where the multi-channel analysis of surface waves method was applied to a site consisting of clay residuum overlying basalt bedrock, inversion for the fundamental-mode Rayleigh wave resulted in shear-wave velocities within the rock that are less than half of expected values. Forward modeling reveals that the fundamental-mode dispersion curve is hardly sensitive to bedrock velocity perturbations over a practical range of wavelengths, leading to poorly constrained solutions. Standard surface-wave methods can …