Open Access. Powered by Scholars. Published by Universities.®

Civil and Environmental Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of Nebraska - Lincoln

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 781 - 810 of 2277

Full-Text Articles in Civil and Environmental Engineering

Environmental Fate And Microbial Effects Of Monensin, Lincomycin, And Sulfamethazine Residues In Soil, Matteo D'Alessio, Lisa M. Durso, Daniel N. Miller, Brian Woodbury, Chittaranjan Ray, Daniel D. Snow Nov 2018

Environmental Fate And Microbial Effects Of Monensin, Lincomycin, And Sulfamethazine Residues In Soil, Matteo D'Alessio, Lisa M. Durso, Daniel N. Miller, Brian Woodbury, Chittaranjan Ray, Daniel D. Snow

Nebraska Water Center: Faculty Publications

The impact of commonly-used livestock antibiotics on soil nitrogen transformations under varying redox conditions is largely unknown. Soil column incubations were conducted using three livestock antibiotics (monensin, lincomycin and sulfamethazine) to better understand the fate of the antibiotics, their effect on nitrogen transformation, and their impact on soil microbial communities under aerobic, anoxic, and denitrifying conditions. While monensin was not recovered in the effluent, lincomycin and sulfamethazine concentrations decreased slightly during transport through the columns. Sorption, and to a limited extent degradation, are likely to be the primary processes leading to antibiotic attenuation during leaching. Antibiotics also affected microbial respiration …


Experimental Study On A New Type Of Transverse Connection For Nebraska County Bridge System, Alexander Bleyhl Nov 2018

Experimental Study On A New Type Of Transverse Connection For Nebraska County Bridge System, Alexander Bleyhl

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

Many county-owned bridges in Nebraska need replacement due to their structural deficiency. Most of the bridges needing replacement are in the 40 to 60 ft range. This span range lacks a standard design that fits Nebraska county practices in terms of speed and simplicity of construction. The current systems being used are (a) Precast 1 by 2 ft planks which can span up to 30 ft, (b) Cast-in-place slab bridges which can span up to 50 ft but require extensive field formwork, concrete placing, and curing, and are best when constructed in three-span units, and (c) Inverted tees which can …


Investigation Of A Tractor-Tank Trailer Roadside Containment Barrier, Dean L. Whitfield Nov 2018

Investigation Of A Tractor-Tank Trailer Roadside Containment Barrier, Dean L. Whitfield

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

The objective of this research project was to develop a new, cost-effective, Manual for Assessing Safety Hardware (MASH) Test Level 6 (TL-6) barrier. A literature review on prior Test Level 5 and Test Level 6 barriers was conducted, and the cost of current TL-5 and TL-6 barriers was established. Existing and modified design procedures for roadside barrier were reviewed as well as current TL-6 design forces. A preliminary TL-6 truck model was developed in LS-DYNA. The minimum barrier height to contain a tractor-tank vehicle was determined to be 62 in. for a rigid, vertical-faced barrier through LS-DYNA computer simulation. New …


Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale Nov 2018

Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale

Adam Liska Papers

Driven by biofuel policies, which aim to reduce greenhouse gas (GHG) emissions and increase domestic energy supply, global production and consumption of bioethanol have doubled between 2007 and 2016, with rapid growth in corn-based bioethanol in the U.S. and sugar cane-based bioethanol in Brazil. Advances in crop yields, energy use efficiency in fertilizer production, biomass-to-ethanol conversion rates, and energy efficiency in ethanol production have improved the energy balance and GHG emission reduction potential of bioethanol. In the current study, the water, energy, and carbon footprints of bioethanol from corn in the U.S. and sugar cane in Brazil were assessed. The …


Evaluation Of The Weak Constraint Data Assimilation Approach For Estimating Turbulent Heat Fluxes At Six Sites, Xinlei He, Tongren Xu, Sayed M. Bateni, C.M.U. Neale, Thomas Auligne, Shaomin Liu, Kaicun Wang, Kebiao Mao, Yunjun Yao Nov 2018

Evaluation Of The Weak Constraint Data Assimilation Approach For Estimating Turbulent Heat Fluxes At Six Sites, Xinlei He, Tongren Xu, Sayed M. Bateni, C.M.U. Neale, Thomas Auligne, Shaomin Liu, Kaicun Wang, Kebiao Mao, Yunjun Yao

Daugherty Water for Food Global Institute: Faculty Publications

A number of studies have estimated turbulent heat fluxes by assimilating sequences of land surface temperature (LST) observations into the strong constraint-variational data assimilation (SC-VDA) approaches. The SC-VDA approaches do not account for the structural model errors and uncertainties in the micrometeorological variables. In contrast to the SC-VDA approaches, the WC-VDA approach (the so-called weak constraint-VDA) accounts for the effects of structural and model errors by adding a model error term. In this study, the WC-VDA approach is tested at six study sites with different climatic and vegetative conditions. Its performance is also compared with that of SC-VDA at the …


Effects Of Moving Bottlenecks On Traffic Operations On Four-Lane Level Freeway Segments, Jianan Zhou Nov 2018

Effects Of Moving Bottlenecks On Traffic Operations On Four-Lane Level Freeway Segments, Jianan Zhou

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

The Highway Capacity Manual (HCM) was developed to provide capacity and level of service analyses for roadway facilities. Trucks may adversely affect the quality of traffic flow on a roadway. In HCM, the passenger car equivalent (PCE) of a truck, which represents the number of passenger cars that have an equivalent effect on traffic flow, is used to account for the impacts of trucks. However, in the past ten years rural freeways in the western rural U.S. have experienced conditions that lie outside the standard HCM conditions. Also, the current HCM truck PCEs may not be appropriate for the western …


Understanding Electricity Bills: Guidance For Nebraska Businesses And Municipalities, Elizabeth M. Regier, Bruce I. Dvorak Nov 2018

Understanding Electricity Bills: Guidance For Nebraska Businesses And Municipalities, Elizabeth M. Regier, Bruce I. Dvorak

Department of Civil and Environmental Engineering: Faculty Publications

This publication is intended to help business owners and municipal managers understand the different types of charges in their electricity bills. By understanding these charges, they may be able to identify ways to reduce their electricity costs.


Statistical Investigation Of Road And Railway Hazardous Materials Transportation Safety, Amirfarrokh Iranitalab Nov 2018

Statistical Investigation Of Road And Railway Hazardous Materials Transportation Safety, Amirfarrokh Iranitalab

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

Transportation of hazardous materials (hazmat) in the United States (U.S.) constituted 22.8% of the total tonnage transported in 2012 with an estimated value of more than 2.3 billion dollars. As such, hazmat transportation is a significant economic activity in the U.S. However, hazmat transportation exposes people and environment to the infrequent but potentially severe consequences of incidents resulting in hazmat release. Trucks and trains carried 63.7% of the hazmat in the U.S. in 2012 and are the major foci of this dissertation. The main research objectives were 1) identification and quantification of the effects of different factors on occurrence and …


Effect Of Swine Manure Pit Additives And Facility Disinfectants On The Fate Of Antibiotics And Manure Composition During Simulated Swine Manure Slurry Storage, Jon Duerschner Nov 2018

Effect Of Swine Manure Pit Additives And Facility Disinfectants On The Fate Of Antibiotics And Manure Composition During Simulated Swine Manure Slurry Storage, Jon Duerschner

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

This thesis investigates the effect of time and of swine manure slurry treatment on the physical properties, nutrient content, and the concentrations of antibiotics chlortetracycline, lincomycin, and tiamulin in simulated storage of swine manure. In one experiment the slurry was treated with six additive products. In a second experiment a set of four disinfectant products were used. Control consisted of unamended slurry. Manure was stored in 60 liter stainless steel bioreactors to simulate deep pit storage and was sampled 7 times over a 40 day incubation.

From an ANOVA of the results, it was concluded that evaporation may be contributing …


Invasion Of The P Elements: Tolerance Is Not Futile, Colin D. Meiklejohn, Justin P. Blumenstiel Oct 2018

Invasion Of The P Elements: Tolerance Is Not Futile, Colin D. Meiklejohn, Justin P. Blumenstiel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Organisms are locked in an eternal struggle with parasitic DNA sequences that live inside their genomes and wreak havoc on their host’s chromosomes as they spread through populations. To combat these parasites, host species have evolved elaborate mechanisms of resistance that suppress their activity. A new study in Drosophila indicates that, prior to the acquisition of resistance, individuals can vary in their ability to tolerate the activity of these genomic parasites, ignoring or repairing the damage they induce. This tolerance results from variation at genes involved in germline development and DNA damage checkpoints and suggests that these highly conserved cellular …


Fungi: A Neglected Candidate For The Application Of Self-Healing Concrete, Congrui Jin, Rui Yu, Zhonghe Shui Oct 2018

Fungi: A Neglected Candidate For The Application Of Self-Healing Concrete, Congrui Jin, Rui Yu, Zhonghe Shui

Department of Civil and Environmental Engineering: Faculty Publications

Self-healing mechanism in concrete has been so far achieved mainly by three approaches: autogenous healing, encapsulation of polymeric material, and biologically induced mineralization of calcium carbonate. The microbial approach prevails over the other two approaches due to the high compatibility between the filler material and the concrete compositions. Although the term “microbe” refers to many different types of organisms, research work on self-healing concrete has been so far restricted to bacteria. In this perspective article, we review the current status of bacteria-mediated self-healing concrete and summarize the prospects for future advances. In particular, we point out that fungi may have …


Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Saptashati Biswas, Mohammedreza Shafieifini, Xu Li, Matteo D'Alessio, Laura Carter, J. Brett Sallach Oct 2018

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Saptashati Biswas, Mohammedreza Shafieifini, Xu Li, Matteo D'Alessio, Laura Carter, J. Brett Sallach

Daugherty Water for Food Global Institute: Faculty Publications

A total of 75 papers published in 2017 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes, and engineered nanoparticles agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Fate and Occurrence, Pharmaceutical Metabolites, Anthelmintics, Antibiotic Resistance Genes, and Engineered Nanomaterials.


Shear Strength Characteristics And Failure Mechanism Of Slopes In Overconsolidated Soils Of Nebraska, Hossein Bahmyari Oct 2018

Shear Strength Characteristics And Failure Mechanism Of Slopes In Overconsolidated Soils Of Nebraska, Hossein Bahmyari

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

Geotechnical engineers deal with some challenging problems when encountering long-term slope stability in overconsolidated clays and clayey shales. One of these problems is determining a suitable method to estimate the reliable shear strength of overconsolidated clayey soils for long-term slope stability. According to Eversol (2013), one half of the counties in Nebraska have experienced slope failure in overconsolidated soils, especially in north and east Nebraska. In this research, shear strength characteristics of overconsolidated clayey soils of Nebraska is investigated in regard to long-term stability of slopes, and the failure mechanism in such soils is examined.

Undisturbed samples from boring logs …


Report Of Community Conversations About Gender Roles In Livestock, Mamusha Lemma, Wole Kinati, Annet Mulema, Zekarias Bassa, Abiro Tigabe, Hiwot Desta, Mesfin Mekonnen, Tadious Asfaw Sep 2018

Report Of Community Conversations About Gender Roles In Livestock, Mamusha Lemma, Wole Kinati, Annet Mulema, Zekarias Bassa, Abiro Tigabe, Hiwot Desta, Mesfin Mekonnen, Tadious Asfaw

Daugherty Water for Food Global Institute: Faculty Publications

The International Livestock Research Institute (ILRI) and the International Center for Research in the Dry Areas (ICARDA) gender and animal health teams facilitated community conversations (CCs) about gender roles in livestock husbandry in three districts in the Southern Nations, Nationalities and Peoples Region (SNNPR) and Amhara region from 30 May–07 June 2018. These dictricts were: Doyogena (Hawora Arara and Ancha Sadicha kebeles) of SNNPR from 30 and 31 May; and Menz Gera district (Sine Amba kebele) and Menz Mama district (Key Afer kebele) of Amhara from June 6–7. In Doyogena, the team held the conversations in farmer training centres (FTCs) …


Measuring Landscape Performance: Case Study Investigation, Hannah Michelle Lopresto, Brandon Zambrano, Catherine De Almeida Aug 2018

Measuring Landscape Performance: Case Study Investigation, Hannah Michelle Lopresto, Brandon Zambrano, Catherine De Almeida

UCARE: Research Products

Participating in the Landscape Architecture Foundation’s 2018 Case Study Investigation has been an incredibly informative experience for our research team at the University of Nebraska-Lincoln. We are eager to shine a spotlight on the landscape performance of two Great Plains projects: P Street Corridor, a revitalized downtown streetscape in Lincoln, Nebraska, and Tom Hanafan River’s Edge Park, a waterfront redevelopment in Council Bluffs, Iowa. Working on the post-occupancy study of both projects has been extremely beneficial in understanding how reclaiming underutilized sites can create high-performing landscapes. Both are public projects in urban settings with primary goals of transforming formerly unpleasant, …


Development Of Iowa Dot Combination Bridge Separation Barrier With Bicycle Railing, Chaz M. Ginger Aug 2018

Development Of Iowa Dot Combination Bridge Separation Barrier With Bicycle Railing, Chaz M. Ginger

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

The Iowa Department of Transportation typically builds separation barriers between vehicle and pedestrian/bicycle facilities when sidewalks or trails are present on vehicular bridges. Currently, Iowa DOT employs a combination bridge rail that utilizes a concrete parapet that previously had been successfully evaluated to National Cooperative Highway Research Program (NCHRP) Report 350 Test Level 4 (TL-4) criteria for these situations. While the parapet had been successfully evaluated, the combination bridge rail system as a whole had not been evaluated to any crash test standards. Iowa DOT desired that researchers at Midwest Roadside Safety Facility (MwRSF) design and test a combination bridge …


Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed Aug 2018

Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed

Department of Agricultural and Biological Systems Engineering: Faculty Publications

One perceived cost of integrating winter cover cropping in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation systems is the potential negative impact on soil water storage available for primary crop production. The objective of this 3-year study was to evaluate the effects of winter cover crops on soil water storage and cover crop biomass production following no-till maize and soybean rotations. Locations were near Brule (west-central), Clay Center (south-central), Concord (northeast), and Mead (east-central), Nebraska, United States. Treatments included crop residue only (no cover crop) and a multi-species cover crop mix, both broadcast-seeded before …


Evaluation And Development Of Cpt Based Pile Design In Nebraska Soils, Alex Silvey Aug 2018

Evaluation And Development Of Cpt Based Pile Design In Nebraska Soils, Alex Silvey

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

Cone penetration testing (CPT) is a well established geotechnical subsurface investigation technique commonly used for site characterization and soil classification. The CPT gives real time end resistance, side friction, and pore pressure readings. Axially loaded piles also share these two resistance mechanisms, suggesting the cone can be considered similar to a miniature pile. This study focused on evaluating eight CPT methods prediction of pile bearing capacity. The Nebraska Department of Roads (NDOR) conducts dynamic load tests (PDA) of driven pile to verify pile capacity for bridge foundations. 91 comparisons of CPT logs and PDA data were evaluated. CPT prediction methods …


Irrigation Management, Environment, And Profits: Who Wins?, Emily O'Donnell Jul 2018

Irrigation Management, Environment, And Profits: Who Wins?, Emily O'Donnell

Department of Agricultural Economics: Dissertations, Theses, and Student Research

The impact of irrigation technology on farmers’ management strategies and resulting environmental benefits depends upon agronomic properties and market forces. We evaluate the role of deficit irrigation using soil moisture probe technology on corn yield and evapotranspiration, which is a measure of water use efficiency. Evapotranspiration represents the water that transits through the plant during planting to harvest (transpiration) and the evaporation from the soil into the environment, or the displaced water in the production process. We develop yield and evapotranspiration response functions to inform a constrained profit maximization model used to identify the optimal irrigation level across a variety …


Plant Community Composition, Floristic Quality, And Establishment Of Roadside Revegetation In Nebraska, Usa, Jonathan M. Soper Jul 2018

Plant Community Composition, Floristic Quality, And Establishment Of Roadside Revegetation In Nebraska, Usa, Jonathan M. Soper

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Roadside revegetation poses a challenge and opportunity for biodiversity conservation, as the land area occupied by roadsides is not expected to decline in the future. In the context of roadside revegetation activities in rural regions dominated by agricultural land uses, revegetation efforts can establish plant communities that offer unique species that would otherwise be absent on the landscape. To determine the efficacy of roadside revegetation efforts in 1) providing plant communities of high biodiversity value and 2) meeting the expectations of roadside revegetation managers for establishment, we quantified botanical composition, floristic quality, and success in seeding efforts to meet manager …


Including Farmer Irrigation Behavior In A Sociohydrological Modeling Framework With Application In North India, Jimmy O’Keeffe, Simon Moulds, Emma Bergin, Nick Brozovic, Ana Mijic, Wouter Buytaert Jul 2018

Including Farmer Irrigation Behavior In A Sociohydrological Modeling Framework With Application In North India, Jimmy O’Keeffe, Simon Moulds, Emma Bergin, Nick Brozovic, Ana Mijic, Wouter Buytaert

Daugherty Water for Food Global Institute: Faculty Publications

Understanding water user behavior and its potential outcomes is important for the development of suitable water resource management options. Computational models are commonly used to assist water resource management decision making; however, while natural processes are increasingly well modeled, the inclusion of human behavior has lagged behind. Improved representation of irrigation water user behavior within models can provide more accurate and relevant information for irrigation management in the agricultural sector. This paper outlines a model that conceptualizes and proceduralizes observed farmer irrigation practices, highlighting impacts and interactions between the environment and behavior. It is developed using a bottom-up approach, informed …


Data-Driven Development Of A Roadside Safety Marketing Campaign For Tree Removal – Phase I, Cody S. Stolle, Thomas Ammon, Chris M. Vargas, Ronald K. Faller, Karla A. Lechtenberg, Erin L. Urbank Jul 2018

Data-Driven Development Of A Roadside Safety Marketing Campaign For Tree Removal – Phase I, Cody S. Stolle, Thomas Ammon, Chris M. Vargas, Ronald K. Faller, Karla A. Lechtenberg, Erin L. Urbank

Nebraska Department of Transportation: Research Reports

Since the 1970s, tree crashes have been one of the most common and deadly fixed-object fatal crash types, resulting in more than 3,000 fatal crashes and 3,500 fatalities each year. While fatal tree crashes could be prevented by removing trees adjacent to the roadway, an extensive national tree removal project would be unnecessary, cost-prohibitive, and would experience significant political resistance.

The Midwest Pooled Fund Program jointly funded a research study to develop marketing methods and approaches which would focus on tree removal, replacement, or relocation in the most critical areas. Researchers conducted an extensive background investigation into tree crashes, other …


Evaluation Of Effectiveness Of Streambank Stabilization Practices And Flood Impact On Cedar River, Nebraska, Naisargi N. Dave Jul 2018

Evaluation Of Effectiveness Of Streambank Stabilization Practices And Flood Impact On Cedar River, Nebraska, Naisargi N. Dave

Department of Environmental Engineering: Theses and Other Student Research

Stream restoration has been a major environmental objective for preserving biodiversity, reducing loss of valuable cropland and improving water quality. The impact and efficiency of streambank stabilization practices has been simulated using erosion-prediction models; however, evaluation of the erosion-control practices to measure their efficiency is often neglected. This project monitored changes in fluvial geomorphology on the Cedar River in Nebraska and quantified the effectiveness of 18 sites with streambank stabilization practices. A flood event in 2010 due to dam failure acted as a major parameter in measuring the efficiency of the erosion control practices. The methodology included aerial imagery to …


Artificial Neural Network And Finite Element Modeling Of Nanoindentation Tests On Silica, Kianoosh Koocheki Jul 2018

Artificial Neural Network And Finite Element Modeling Of Nanoindentation Tests On Silica, Kianoosh Koocheki

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

Two major forms of Silica include the crystalline form named Quartz which consist of the sand grains in nature, and amorphous form named Silica Glass or Fused Silica which is commonly known as glass. Fused Silica is an amorphous crystal that can show plastic behavior at micro-scale despite its brittle behavior in large scales. Due to the amorphous and ductile nature of Fused Silica, this behavior may not be explained well using the traditional dislocation-based mechanism of plasticity for crystalline solids. The crystal plasticity happens due to shear stress and stored energy in the material as dislocations which does not …


Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira Jul 2018

Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A three-dimensional Control Volume Finite Difference-based numerical groundwater flow model was constructed to assess the effects of agricultural irrigation and land use change on streamflow depletion. The study area is Frenchman Creek basin located in southwestern corner of the State of Nebraska, USA. This area was subject to an increased proliferation of groundwater abstraction for agricultural purposes since industrial revolution. It has also been subject to land use change from native rangeland to dry and irrigated cropland. The groundwater flow model was spatially discretized using Voronoi cells in unstructured grid built with the USGS MODFLOW-6. Temporal discretization defined 151 time …


Evaluating Opportunities And Barriers To Improving The Energy Efficiency Of Small Nebraska Wastewater Treatment Plants, Matthew J. Thompson Jul 2018

Evaluating Opportunities And Barriers To Improving The Energy Efficiency Of Small Nebraska Wastewater Treatment Plants, Matthew J. Thompson

Department of Environmental Engineering: Theses and Other Student Research

Wastewater treatment plants (WWTP)s account for about 0.8% of U.S. electricity use. Small WWTPs serving communities of populations less than 10,000 accounts for 95% of treatment plants in Nebraska. These plants are significantly less efficient compared to large systems and thus improving their energy efficiency (E2) is a growing focus in efforts to reduce greenhouse gas emissions associated with their operation. Energy use of plant unit operations was evaluated for several plants and included analysis of energy for space heating. Specific infrastructure and/or operational changes reported by operators following an E2 benchmarking project were evaluated by quantifying the change in …


Development Of The Nebraska Department Of Transportation Winter Severity Index, Mark R. Anderson, Behzad Esmaeili, Curtis L. Walker, Dylan Steinkruger, Sogand Hasanzadeh, Pouya Gholizadeh, Bac Dao Jun 2018

Development Of The Nebraska Department Of Transportation Winter Severity Index, Mark R. Anderson, Behzad Esmaeili, Curtis L. Walker, Dylan Steinkruger, Sogand Hasanzadeh, Pouya Gholizadeh, Bac Dao

Nebraska Department of Transportation: Research Reports

Adverse weather conditions are responsible for millions of vehicular crashes, thousands of vehicular deaths and billions of dollars in economic and congestion costs. Many transportation agencies utilize a performance or mobility metric to assess how well they are maintaining road access. This research focuses on the development of a winter severity index for the State of Nebraska (NEWINS). NEWINS is an event-driven index that was derived for the Nebraska Department of Transportation (NDOT) and its districts across the state. The NEWINS framework includes a categorical storm classification framework and climatological aspect to capture atmospheric conditions more accurately across the diverse …


Tradeoffs In Model Performance And Effort For Long-Term Phosphorus Leaching Based On In Situ Field Data, Ryan P. Freiberger, Derek M. Heeren, Dean E. Eisenhauer, Aaron R. Mittelstet, Guillermo Baigorria Jun 2018

Tradeoffs In Model Performance And Effort For Long-Term Phosphorus Leaching Based On In Situ Field Data, Ryan P. Freiberger, Derek M. Heeren, Dean E. Eisenhauer, Aaron R. Mittelstet, Guillermo Baigorria

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Phosphorus and N are critical nutrients for agriculture but are also responsible for surface water enrichment that leads to toxic algal growth. Although P loading to surface waters has traditionally been thought to occur primarily in surface runoff, contributions from subsurface transport can also be significant. The primary objectives of this research were to evaluate several methods of representing macropore flow and transport in a finite element model using plot-scale infiltration and leaching data and to compare several models of various levels of complexity to simulate long-term P leaching. To determine flow and transport parameters, single- and dual-porosity models in …


Portable Flux Tower Deployments Field Campaign Report, M. S. Torn, L Kuepper, S. C. Biraud, D. P. Billesbach Jun 2018

Portable Flux Tower Deployments Field Campaign Report, M. S. Torn, L Kuepper, S. C. Biraud, D. P. Billesbach

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Contents

Acronyms and Abbreviations...................................................................... iii

1.0 Summary ....................................................... 1

2.0 Results ........................................... 1

3.0 Publications and References ................................................. 2

4.0 Lessons Learned .................................................................... 2


3-D Reconstructions And Numerical Simulations Of Precarious Rocks In Southern California, Christine E. Wittich, Tara C. Hutchinson, J. Desanto, D. Sandwell Jun 2018

3-D Reconstructions And Numerical Simulations Of Precarious Rocks In Southern California, Christine E. Wittich, Tara C. Hutchinson, J. Desanto, D. Sandwell

Department of Civil and Environmental Engineering: Faculty Publications

Reliable estimates of seismic hazard are essential for the development of resilient communities; however, estimates of rare, yet high intensity earthquakes are highly uncertain due to a lack of observations and recordings. Lacking this data, seismic hazard analyses may be based on extrapolations from earthquakes with more moderate return periods, which can lead to physically unrealistic earthquake scenarios. However, the existence of certain precariously balanced rocks (PBRs) has been identified as an indicator of an upper bound ground motion, which precludes toppling of the balanced rock, over its lifetime. To this end, a survey of PBRs was conducted in proximity …