Civil and Environmental Engineering Commons^™

Reliability And Sensitivity Analysis For Micro-Meteoroids And Orbital Debris Protection Models Using First-Order Reliability Methods (Form)., Levi Pereda

Open Access Theses & Dissertations

Abstract This Thesis provides a probabilistic assessment of the micro-meteoroids and orbital debris (MMOD) impact protection structures. The assessment is based on first-order reliability methods that use Ballistic Limit equations traditionally used by NASA for the design of shields. The research demonstrates how the structural reliability methods can be implemented into the aeronautics and astronautics field. NASA is continuously developing new techniques that allow the consideration of the uncertainty that exists in the design of their space structures. Nevertheless, some of their design approaches are still deterministic. For example MMOD ballistic limit equations used for the design of the MMOD …

Advanced Thermo-Mechanical Characterization Of Organic Materials By Piezoresistive Organic Resonators, D. Thuau, C. Ayela, E. Lemaire, Stephen M. Heinrich, P. Poulin, Isabelle Dufour

Civil and Environmental Engineering Faculty Research and Publications

We present the piezoresistive transduction of an all-organic microelectromechanical system (MEMS) based resonant sensor fabricated through a low-cost and highly versatile process. The MEMS resonator consists of a U-shaped cantilever beam resonator made of a thin layer of a piezoresistive nanocomposite (SU/8 epoxy resin filled with industrially produced carbon nanotubes, or CNTs) deposited on flexible substrates such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN) and paper. The structures have been fabricated using a commercially available vinyl cutting machine. External piezoelectric actuation has been used to drive the devices into resonance while integrated piezoresistive transduction has been chosen as the resonance …

Prediction Of Load Capacity Variation In Frp Bonded Concrete Specimens Using Brownian Motion, Tayyebeh Mohammadi, Baolin Wan, Jian-Guo Dai, Chao Zhu

Civil and Environmental Engineering Faculty Research and Publications

In wet lay-up process, dry fiber sheets are saturated with a polymer and applied to the concrete surface by hand. This causes relatively large variation in properties of the cured FRP composite material. It is hard to know the exact mechanical properties of the FRP constructed by wet lay-up process. In addition, the stiffness of FRP changes during debonding process due to different amount of concrete attached to the debonded FRP at different locations. It is also inevitable to have considerable variations in the strength of concrete. Therefore, the behaviour of FRP bonded concrete members varies among specimens even when …

The Impact Of Triclosan On The Spread Of Antibiotic Resistance In The Environment, Daniel E. Carey, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Triclosan (TCS) is a commonly used antimicrobial agent that enters wastewater treatment plants (WWTPs) and the environment. An estimated 1.1 × 10⁵ to 4.2 × 10⁵ kg of TCS are discharged from these WWTPs per year in the United States. The abundance of TCS along with its antimicrobial properties have given rise to concern regarding its impact on antibiotic resistance in the environment. The objective of this review is to assess the state of knowledge regarding the impact of TCS on multidrug resistance in environmental settings, including engineered environments such as anaerobic digesters. Pure culture studies are reviewed …

Uncertainty Analysis Of An Irrigation Scheduling Model For Water Management In Crop Production, S. Mun, G. F. Sassenrath, Amy M. Schmidt, N. Lee, M. C. Wadsworth, B. Rice, Jason Q, Corbitt, J. M. Schneider, M. L. Tagert, J. Pote, R. Prabhu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigation scheduling tools are critical to allow producers to effectively manage water resources for crop production. To be useful, these tools need to be accurate, complete, and relatively reliable. The current work presents an uncertainty analysis and its results for the Mississippi Irrigation Scheduling Tool (MIST) model, showing the margin of error (uncertainty) of the resulting irrigation advice arising solely from the propagation of measurement uncertainty through the MIST calculations. The final relative uncertainty in the water balance value from MIST was shown to be around 9% of that value, which is in the normal range of the margin of …

Development Of A Turbidity Prediction Methodology For Runoff-Erosion Models, Sagar Neupane, Jason R. Vogel, Daniel E. Storm, Bill J. Barfield, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Surface water bodies can be impaired by turbidity and excessive sediment loading due to urban development, construction activities, and agricultural practices. Turbidity has been considered as a proxy for evaluating water quality, aquatic habitat, and aesthetic impairments in surface waters. The US Environment Protection Agency (USEPA) has listed turbidity and sediment as major pollutants for construction site effluent. Recently proposed USEPA regulations for construction site runoff led to increased interest in methods to predict turbidity in runoff based on parameters that are more commonly predicted in runoff- erosion models. In this study, a turbidity prediction methodology that can be easily …

Robust Estimates Of Soil Moisture And Latent Heat Flux Coupling Strength Obtained From Triple Collocation, Wade T. Crow, Fangni Lei, Christopher R. Hain, Martha C. Anderson, Russell L. Scott, David P. Billesbach, Timothy Arkebauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Land surface models (LSMs) are often applied to predict the one-way coupling strength between surface soil moisture (SM) and latent heat (LH) flux. However, the ability of LSMs to accurately represent such coupling has not been adequately established. Likewise, the estimation of SM/LH coupling strength using ground-based observational data is potentially compromised by the impact of independent SM and LH measurements errors. Here we apply a new statistical technique to acquire estimates of one-way SM/LH coupling strength which are nonbiased in the presence of random error using a triple collocation approach based on leveraging the simultaneous availability of independent SM …

Using Swat To Simulate Crop Yields And Salinity Levels In The North Fork River Basin, Usa, Aaron R. Mittelstet, Daniel E. Storm, Art L. Stoecker

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Crop yields and salinity levels in the North Fork of the Red River (North Fork River) basin, located in southwestern Oklahoma and the Texas Panhandle, were analyzed based on the diverse climate in the region. Saline irrigation water is a major problem in the basin. The Elm Fork Creek flows through salt deposits, making the creek and its receiving stream, the North Fork River, too saline to use for irrigation. This greatly reduces the number of hectares that can be utilized for agricultural crops within the basin. A baseline SWAT model was setup, calibrated and validated to simulate streamflow and …

Identifying Intracellular Pdna Losses From A Model Of Nonviral Gene Delivery, Timothy Michael Martin, Beata Joanna Wysocki, Tadeusz Antoni Wysocki, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nonviral gene delivery systems are a type of nanocommunication system that transmit plasmid packets (i.e., pDNA packets) that are programmed at the nanoscale to biological systems at the microscopic cellular level. This engineered nanocommunication system suffers large pDNA losses during transmission of the genetically encoded information, preventing its use in biotechnological and medical applications. The pDNA losses largely remain uncharacterized, and the ramifications of reducing pDNA loss from newly designed gene delivery systems remain difficult to predict. Here, the pDNA losses during primary and secondary transmission chains were identified utilizing a MATLAB model employing queuing theory simulating delivery of pEGFPLuc …

Narrow Grass Hedges Reduce Tylosin And Associated Antimicrobial Resistance Genes In Agricultural Runoff, Bhavneet Soni, Shannon L. Bartelt-Hunt, Daniel D. Snow, John E. Gilley, Bryan Woodbury, David B. Marx, Xu Li

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Agricultural runoff from areas receiving livestock manure can potentially contaminate surface water with antimicrobials and antimicrobial resistance genes (ARGs). The objective of this study was to investigate the effectiveness of narrow grass hedges (NGHs) on reducing the transport of antimicrobials and ARGs in runoff after land application of swine manure slurry. Plot-scale rainfall simulation tests were conducted on 0.75 m by 4.0 m plots designed to test three treatment factors: manure amendment (control plots receiving no manure vs. amended plots receiving manure based on 3 times N requirement), NGH (plots with a NGH vs. plots without a NGH), and rainfall …

Surface Energy Balance, Evapotranspiration, And Surface Coefficients During Non-Growing Season In A Maize-Soybean Cropping System, Lameck O. Odhiambo, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Surface energy balance components, including actual evapotranspiration (ET), were measured in a reducedtill maize-soybean field in south central Nebraska during three consecutive non-growing seasons (2006/2007, 2007/2008, and 2008/2009). The relative fractions of the energy balance components were compared across the non-growing seasons, and surface coefficients (K_c) were determined as a ratio of measured ET to estimated alfalfa (ET_r) and grass (ET_o) reference ET (ET_ref). The non-growing season following a maize crop had 25% to 35% more field surface covered with crop residue as compared to the non-growing seasons following soybean crops. Net …

Temporal Endogenous Gene Expression Profiles In Response To Lipid-Mediated Transfection, Timothy M. Martin, Sarah A. Plautz, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background — Design of efficient nonviral gene delivery systems is limited as a result of the rudimentary understanding of the specific molecules and processes that facilitate DNA transfer.

Methods — Lipoplexes formed with Lipofectamine 2000 (LF2000) and plasmid-encoding green fluorescent protein (GFP) were delivered to the HEK 293T cell line. After treating cells with lipoplexes, HG-U133 Affymetrix microarrays were used to identify endogenous genes differentially expressed between treated and untreated cells (2 h exposure) or between flow-separated transfected cells (GFP+) and treated, untransfected cells (GFP–) at 8, 16 and 24 h after lipoplex treatment. Cell priming studies were conducted using …

Temporal Endogenous Gene Expression Profiles In Response To Polymer-Mediated Transfection And Profile Comparison To Lipid-Mediated Transfection, Timothy M. Martin, Sarah A. Plautz, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background Design of efficient nonviral gene delivery systems is limited by the rudimentary understanding of specific molecules that facilitate transfection.

Methods Polyplexes using 25-kDa polyethylenimine (PEI) and plasmid encoding green fluorescent protein (GFP) were delivered to HEK 293T cells. After treating cells with polyplexes, microarrays were used to identify endogenous genes differentially expressed between treated and untreated cells (2 h of exposure) or between flow-separated transfected cells (GFP+) and treated, untransfected cells (GFP–) at 8, 16 and 24 h after lipoplex treatment. Cell priming studies were conducted using pharmacologic agents to alter endogenous levels of the identified differentially expressed genes …

Vulnerability Of Crops And Native Grasses To Summer Drying In The U.S. Southern Great Plains, Naama Raz-Yaseef, Dave P. Billesbach, Marc L. Fischer, Sebastien C. Biraud, Stacey A. Gunter, James A. Bradford, Margaret S. Torn

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Southern Great Plains are characterized by a fine-scale mixture of different land-cover types, predominantly winter-wheat and grazed pasture, with relatively small areas of other crops, native prairie, and switchgrass. Recent droughts and predictions of increased drought in the Southern Great Plains, especially during the summer months, raise concern for these ecosystems. We measured ecosystem carbon and water fluxes with eddy-covariance systems over cultivated cropland for 10 years, and over lightly grazed prairie and new switchgrass fields for 2 years each. Growing-season precipitation showed the strongest control over net carbon uptake for all ecosystems, but with a variable effect: grasses …

A Sustainable Slashing Industry Using Biodegradable Sizes From Modified Soy Protein To Replace Petro-Based Poly(Vinyl Alcohol), Yi Zhao, Yuzhu Zhao, Helan Xu, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biodegradable sizing agents from triethanolamine (TEA) modified soy protein could substitute poly(vinyl alcohol)(PVA) sizes for high-speed weaving of polyester and polyester/cotton yarns to substantially decrease environmental pollution and impel sustainability of textile industry. Nonbiodegradable PVA sizes are widely used and mainly contribute to high chemical oxygen demand (COD) in textile effluents. It has not been possible to effectively degrade, reuse or replace PVA sizes so far. Soy protein with good biodegradability showed potential as warp sizes in our previous studies. However, soy protein sizes lacked film flexibility and adhesion for required high-speed weaving. Additives with multiple hydroxyl groups, nonlinear molecule, …

Sustainable And Hydrolysis-Free Dyeing Process For Polylactic Acid Using Nonaqueous Medium, Suxin Xu, Jiangang Chen, Bijia Wang, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A sustainable and hydrolysis-free dyeing process was developed for polylactic acid (PLA) fibers. PLA is a biobased alternative to petroleum based polyethylene terephthalate (PET), which is the most widely used textile fiber. However, the hydrolytic degradation of PLA fibers under the conventional aqueous dyeing conditions limited its applications in textile industry. A new solvent dyeing process was developed using liquid paraffin as a nonaqueous dyeing medium. High quality dyed PLA fabrics were obtained without consuming water and auxiliaries. Minimal strength loss of dyed fibers was achieved by postheat setting treatment. The 3R principle (reduce, reuse, and recycle) was implemented to …

Robust And Flexible Films From 100% Starch Cross-Linked By Biobased Disaccharide Derivative, Helan Xu, Hazal Canisag, Bingnan Mu, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In this research, oxidized sucrose, a novel aldehyde-based green cross-linker, endowed starch films with substantial improvement in both tensile strength and elongation, whereas many other cross-linkers did not. Starch films are usually weak, brittle, and highly moisture sensitive, and thus have restricted industrial applications. Cross-linking is one of the most common methods to tackle these problems. However, most of the available cross-linkers are either toxic, expensive, or with low cross-linking efficiencies. Oxidized sucrose is a green cross-linker with multiple aldehyde groups per molecule to cross-link starch molecules via forming hemiacetals/acetals. The starch films cross-linked with oxidized sucrose had tensile strength …

Chitosan-Alginate Scaffold Cell Culture System And Related Methods, Miqin Zhang, Forrest Kievit, Matthew Chi-Hang Leung, Stephen Florczyk

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Methods for culturing cancer cells in vitro using a three dimensional scaffold, scaffolds that include the cultured cancer cells, and methods for using the cultured cancer cells and the scaffolds that include the cultured cancer cells in anticancer therapeutic drug development.

Bionanotechnology And The Future Of Glioma, Peter A. Chiarelli, Forrest M. Kievit, Miqin Zhang, Richard G. Ellenbogen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Designer nanoscaled materials have the potential to revolutionize diagnosis and treatment for glioma. This review summarizes current progress in nanoparticle‑based therapies for glioma treatment including targeting, drug delivery, gene delivery, and direct tumor ablation. Preclinical and current human clinical trials are discussed. Although progress in the field has been significant over the past decade, many successful strategies demonstrated in the laboratory have yet to be implemented in human clinical trials. Looking forward, we provide examples of combined treatment strategies, which harness the potential for nanoparticles to interact with their biochemical environment, and simultaneously with externally applied photons or magnetic fields. …

Nanoparticle Mediated Silencing Of Dna Repair Sensitizes Pediatric Brain Tumor Cells To Y-Irradiation, Forrest M. Kievit, Zachary R. Stephen, Kui Wang, Christopher J. Dayringer, Jonathan G. Sham, Richard G. Ellenbogen, John R. Silber, Miqin Zhang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Medulloblastoma (MB) and ependymoma (EP) are the most common pediatric brain tumors, afflicting 3000 children annually. Radiotherapy (RT) is an integral component in the treatment of these tumors; however, the improvement in survival is often accompanied by radiation-induced adverse developmental and psychosocial sequelae. Therefore, there is an urgent need to develop strategies that can increase the sensitivity of brain tumors cells to RT while sparing adjacent healthy brain tissue. Apurinic endonuclease 1 (Ape1), an enzyme in the base excision repair pathway, has been implicated in radiation resistance in cancer. Pharmacological and specificity limitations inherent to small molecule inhibitors of Ape1 …

Integrating Ecological And Engineering Concepts Of Resilience In Microbial Communities, Hyun-Seob Song, Ryan S. Renslow, Jim K. Fredrickson, Stephen R. Lindemann

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Many definitions of resilience have been proffered for natural and engineered ecosystems, but a conceptual consensus on resilience in microbial communities is still lacking. We argue that the disconnect largely results from the wide variance in microbial community complexity, which range from compositionally simple synthetic consortia to complex natural communities, and divergence between the typical practical outcomes emphasized by ecologists and engineers. Viewing microbial communities as elasto-plastic systems that undergo both recoverable and unrecoverable transitions, we argue that this gap between the engineering and ecological definitions of resilience stems from their respective emphases on elastic and plastic deformation, respectively. We …

Lidar Scanning With Supplementary Uav Captured Images For Structural Inspections, Richard L. Wood, Mohammad Ebrahim Mohammadi

Department of Civil and Environmental Engineering: Faculty Publications

Structural assessment using remote sensing technologies can be performed efficiently and effectively using such technologies as LiDAR (light detection and ranging). LiDAR can be employed for various structural assessments, such as as-built conditions for a newly constructed facility, routine inspection during its service life, or structural collapse evaluation after a natural hazard or extreme event. However, the main disadvantage of LiDAR is that it is a line-of-sight technology that can result in significant occlusions. Architectural or structural components can be partially or fully occluded by another object with respect to the location of the laser scanner. Supplemental photogrammetry techniques, such …

Restricted Salt Diffusion In A Geosynthetic Clay Liner, Michael A. Malusis, Jong Beom Kang, Charles D. Shackelford

Faculty Journal Articles

No abstract provided.

Underwater Sound Transmission Through Arrays Of Disk Cavities In A Soft Elastic Medium, David C. Calvo, Abel L. Thangawng, Christopher N. Layman Jr., Riccardo Casalini, Shadi F. Othman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Scattering from a cavity in a soft elastic medium, such as silicone rubber, resembles scattering from an underwater bubble in that low-frequency monopole resonance is obtainable in both cases. Arrays of cavities can therefore be used to reduce underwater sound transmission using thin layers and low void fractions. This article examines the role of cavity shape by microfabricating arrays of disk-shaped air cavities into single and multiple layers of polydimethylsiloxane. Comparison is made with the case of equivalent volume cylinders which approximate spheres. Measurements of ultrasonic underwater sound transmission are compared with finite element modeling predictions. The disks provide a …

The Skill Of Seasonal Ensemble Low-Flow Forecasts In The Moselle River For Three Different Hydrological Models, Mehmet C. Demirel, Martijn Booij, Arjen Hoekstra

Civil and Environmental Engineering Faculty Publications and Presentations

This paper investigates the skill of 90-day low-flow forecasts using two conceptual hydrological models and one data-driven model based on Artificial Neural Networks (ANNs) for the Moselle River. The three models, i.e. HBV, GR4J and ANN-Ensemble (ANN-E), all use forecasted meteorological inputs (precipitation P and potential evapotranspiration PET), whereby we employ ensemble seasonal meteorological forecasts. We compared low-flow forecasts for five different cases of seasonal meteorological forcing: (1) ensemble P and PET forecasts; (2) ensemble P forecasts and observed climate mean PET; (3) observed climate mean P and ensemble PET forecasts; (4) observed climate mean P and PET and (5) …

Modeling The Effects Of Congestion On Fuel Economy For Advanced Power Train Vehicles, Alexander Y. Bigazzi, Kelly J. Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

This paper describes research undertaken to establish plausible fuel-speed curves (FSC) for hypothetical advanced power train vehicles. These FSC are needed to account for the effects of congestion in long-term transportation scenario analysis considering fuel consumption and emissions. We use the PERE fuel consumption model with real-world driving schedules and a range of vehicle characteristics to estimate fuel economy (FE) in varying traffic conditions for light-duty internal combustion engine (ICE) vehicles, hybrid gas-electric vehicles (HEV), fully electric vehicles (EV), and fuel cell vehicles (FCV). FSC are fit to model results for each of 145 hypothetical vehicles. Analysis of the FSC …

Adjusting Ite’S Trip Generation Handbook For Urban Context, Kelly J. Clifton, Kristina Marie Currans, Christopher D. Muhs

Civil and Environmental Engineering Faculty Publications and Presentations

This study examines the ways in which urban context affects vehicle trip generation rates across three land uses. An intercept travel survey was administered at 78 establishments (high-turnover restaurants, convenience markets, and drinking places) in the Portland, Oregon, region during 2011. This approach was developed to adjust the Institute of Transportation Engineers (ITE) Trip Generation Handbook vehicle trip rates based on built environment characteristics where the establishments were located. A number of policy-relevant built environment measures were used to estimate a set of nine models predicting an adjustment to ITE trip rates. Each model was estimated as a single measure: …

Workshop Synthesis: Built Environment And Contextual Variables, Kelly Clifton, Pascal Perez

Civil and Environmental Engineering Faculty Publications and Presentations

This two-day workshop focused on the important issue of how to define, convey and understand the built environment context as it relates to transport decisions. The field has grown tremendously over the last few decades, fueled in part by the increasing availability of archived spatial data about the environment and geo-referencing activity and travel patterns. But there are persistent issues particularly with inconsistencies in data format or availability across locations that hamper efforts to advance our understanding across regions. Further, there are new challenges in how we communicate context to survey respondents, particularly in stated preference surveys. Much of the …

Empirical Evaluation Of Transit Signal Priority Through Fusion Of Heterogeneous Transit And Traffic Signal Data And Novel Performance Measures, Wei Feng, Miguel A. Figliozzi, Robert Bertini

Civil and Environmental Engineering Faculty Publications and Presentations

Transit signal priority (TSP) can reduce transit delay at signalized intersections by making phasing adjustments. TSP is a relatively inexpensive and easy to implement tool to make transit service faster and more reliable. TSP also sends a signal that a city or region encourages the growth of transit mode split. With the aim of assessing the performance of an existing TSP system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a timely and effective TSP system requires a high …

A Level-Of-Service Model For Protected Bike Lanes, Nick Foster, Christopher Monsere, Jennifer Dill, Kelly Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

Several methods exist for quantifying the quality of service provided by a roadway from a bicyclist’s perspective; however, many of these models do not consider physically protected bike lanes and, of those that do, none is based on empirical data from the US. This is problematic as engineers, planners, and elected officials are increasingly looking to objective performance measures to help guide transportation project design and funding prioritization decisions. This paper addresses this gap by presenting a cumulative logistic model to predict user comfort on protected bike lanes developed from data collected during in-person video surveys. The surveys were conducted …