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

Engineering Commons™

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

Environmental Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 4051 - 4080 of 6955

Full-Text Articles in Engineering

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki Jan 2019

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki

Publications and Research

In this report, we present historical time series of surface area, volume, and elevation for lakes Azuei (Haiti) and Enriquillo (Dominican Republic). The intention is to present a history of the lakes’ levels for both bodies of water as derived from Landsat imagery that is augmented by reports and narratives that reach further back in time. We also summarize lake level time series data collected and developed through various other efforts and compare these data sets to our time series. The time series contains 45 years’ worth of data ranging from 1972 to 2017 which we developed from Landsat imagery …


Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic Jan 2019

Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Understanding how irrigation is used across agricultural landscapes is essential to support efforts to grow more food while reducing pressures on limited freshwater resources. However, to date, few studies have analyzed the underlying spatial and temporal variability in farmers’ individual water use decisions at a landscape scale.Wecompare estimates of irrigation water requirements derived using state-of-the-art remote sensing models with metered abstraction records for 1400 fields over a 13 year period in the US state of Nebraska, one of the world’s most intensively irrigated agricultural regions. Weshow that farmers’ observed water use decisions often diverge significantly from biophysical estimates of crop …


Absorber And Window Study – Cdsexte1-X/Cdte Thin Film Solar Cells, Chih-An Hsu Jan 2019

Absorber And Window Study – Cdsexte1-X/Cdte Thin Film Solar Cells, Chih-An Hsu

USF Tampa Graduate Theses and Dissertations

CdTe an II-VI semiconductor has been a leading thin film photovoltaic material due to its near ideal bandgap and high absorption coefficient [1]. The typical thin film CdTe solar cells have been of the superstrate configuration with CdS (Eg-2.42eV) as the n-type heterojunction partner. Due to the relatively narrow bandgap of CdS, a wider bandgap n-type window layer has recently emerged as a promising substitute: alloys of MgyZn1-yO have been successfully used as the emitter or window layer. The benefits in the usage of MgyZn1-yO (MZO) are its tunable bandgap and wide optical spectrum on optoelectronic devices. Due to an …


An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt Jan 2019

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m3 (142 ft3) of marsh soil and 3.88 m3 (137 ft3) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These …


Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray Jan 2019

Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

In the race to enhance agricultural productivity, irrigation will become more dependent on poorly characterized and virtually unmonitored sources of water. Increased use of irrigation water has led to impaired water and soil quality in many areas. Historically, soil salinization and reduced crop productivity have been the primary focus of irrigation water quality. Recently, there is increasing evidence for the occurrence of geogenic contaminants in water. The appearance of trace elements and an increase in the use of wastewater has highlighted the vulnerability and complexities of the composition of irrigation water and its role in ensuring proper crop growth, and …


Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands Jan 2019

Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands

Daugherty Water for Food Global Institute: Faculty Publications

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused …


Impact Of The Application Of Domestic Wastewater By Subsurface Drip Irrigation On The Soil Solution In Sugarcane Cultivation, Aline Azevedo Nazário, Ivo Zution Gonçalves, Eduardo Augusto Agnellos Barbosa, Leonardo Nazário Silva Dos Santos, Daniel Rodrigues Cavalcante Feitosa, Edson Eiji Matsura Jan 2019

Impact Of The Application Of Domestic Wastewater By Subsurface Drip Irrigation On The Soil Solution In Sugarcane Cultivation, Aline Azevedo Nazário, Ivo Zution Gonçalves, Eduardo Augusto Agnellos Barbosa, Leonardo Nazário Silva Dos Santos, Daniel Rodrigues Cavalcante Feitosa, Edson Eiji Matsura

Daugherty Water for Food Global Institute: Faculty Publications

The agricultural use of domestic sewage is a viable alternative for recycling nutrients; however, there is concern regarding the impact of its use due to the concentration of chemical elements present in this type of effluent. The use of principal component analysis determines the existence or lack of anomalous samples and the relations between measured variables and their relative contribution among samples that help in monitoring the impact of the use of effluents on soil chemical components. Thus, the objective of this work was to identify nutrient ions present in the soil solution during the first ratoon sugarcane irrigated with …


Public Attitudes About Private Forest Management And Government Involvement In The Southeastern United States, Melissa M. Kreye, Renata Rimsaite, Damian C. Adams Jan 2019

Public Attitudes About Private Forest Management And Government Involvement In The Southeastern United States, Melissa M. Kreye, Renata Rimsaite, Damian C. Adams

Daugherty Water for Food Global Institute: Faculty Publications

In the southern United States the country’s top wood-producing region, factors such as intergenerational land transfer and population spillover from urban areas have resulted in forestland conversion and reduced production of critical ecosystem services associated with forest systems (e.g., timber, clean water supply, wildlife habitat). Public attitudes, which drive forestland policy prescriptions, may also be evolving due to the way people experience and perceive forests (e.g., recreation), and think about the role of government in private forest decisions. These changes have significant implications for forestland management and the forest-based economy, both locally and globally. We present the results of a …


Mapping Regional Turbulent Heat Fluxes Via Assimilation Of Modis Land Surface Temperature Data Into An Ensemble Kalman Smoother Framework, Xinlei He, Tongren Xu, Sayed M. Bateni, Christopher M. U. Neale, Shaomin Liu, Thomas Auligne, Kaicun Wang, Shoudong Zhu Jan 2019

Mapping Regional Turbulent Heat Fluxes Via Assimilation Of Modis Land Surface Temperature Data Into An Ensemble Kalman Smoother Framework, Xinlei He, Tongren Xu, Sayed M. Bateni, Christopher M. U. Neale, Shaomin Liu, Thomas Auligne, Kaicun Wang, Shoudong Zhu

Daugherty Water for Food Global Institute: Faculty Publications

Estimation of turbulent heat fluxes via variational data assimilation (VDA) approaches has been the subject of several studies. The VDA approaches need an adjoint model that is difficult to derive. In this study, remotely sensed land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) are assimilated into the heat diffusion equation within an ensemble Kalman smoother (EnKS) approach to estimate turbulent heat fluxes. The EnKS approach is tested in the Heihe River Basin (HRB) in northwest China. The results show that the EnKS approach can estimate turbulent heat fluxes by assimilating low temporal resolution LST data from …


Agricultural Water Transfers In The Western United States, Richael Young, Nicholas Brozovic Jan 2019

Agricultural Water Transfers In The Western United States, Richael Young, Nicholas Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Irrigation for agricultural production represents the largest consumptive use of water in the western United States. Understanding the ways in which agricultural producers respond to physical and institutional water scarcity is therefore key to managing water risk. One of the important risk management tools available to agricultural producers is the ability to transfer water across space and time. Water transfers range from very informal handshake agreements between neighbors to very formal transfers of real property across large distances with mandatory state and federal reporting. Given the range of potential water transfer mechanisms, there are significant knowledge gaps on the variety, …


2019 Nebraska Water Productivity Report, Mesfin Mekonnen, Christopher Michael Usher Neale, Chittaranjan Ray, Galen E. Erickson, Adam Liska, Haishun Yang, Thiago L. Romanelli, Arjen Y. Hoekstra Jan 2019

2019 Nebraska Water Productivity Report, Mesfin Mekonnen, Christopher Michael Usher Neale, Chittaranjan Ray, Galen E. Erickson, Adam Liska, Haishun Yang, Thiago L. Romanelli, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Nebraska’s agricultural production is diverse and vast, ranking the state fourth in total value of agricultural products in the U.S. The state is a national leader in terms of agricultural production: it is the third largest producer of corn and second largest in cattle production. Nebraska is also the second largest producer of ethanol and distillers’ grains. The production and use of these three commodities are highly interlinked. Corn is a major input in livestock feed and the ethanol industry. Ethanol plants then produce distillers’ grains as a co-product that is also used as livestock feed, thus forming what the …


Process Sustainability Evaluation For Manufacturing Of A Component With The 6r Application, Ana E. Bonilla Hernández, Tao Lu, Tomas Beno, Claes Fredriksson, Ibrahim S. Jawahir Jan 2019

Process Sustainability Evaluation For Manufacturing Of A Component With The 6r Application, Ana E. Bonilla Hernández, Tao Lu, Tomas Beno, Claes Fredriksson, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainability in manufacturing can be evaluated at product, process and system levels. The 6R methodology for sustainability enhancement in manufacturing processes includes: reduced use of materials, energy, water and other resources; reusing of products/components; recovery and recycling of materials/components; remanufacturing of products; and redesigning of products to utilize recovered materials/resources. Although manufacturing processes can be evaluated by their productivity, quality and cost, process sustainability assessment makes it a complete evaluation. This paper presents a 6R-based evaluation method for sustainable manufacturing in terms of specific metrics within six major metrics clusters: environmental impact, energy consumption, waste management, cost, resource utilization and …


Ignatian Pedagogy For Sustainability To Support Community-Based Projects: Client-Focused Sustainable Energy Solutions, Andrew Baruth Jan 2019

Ignatian Pedagogy For Sustainability To Support Community-Based Projects: Client-Focused Sustainable Energy Solutions, Andrew Baruth

Jesuit Higher Education: A Journal

Seeing the words of Laudato Si’ as a call to action, we are engaging students in Ignatian Pedagogy for Sustainability through a series of community-based projects with the goal of client-focused sustainable energy solutions and associated dialogue. We outline the development of a purpose-created Energy Technology undergraduate program housed in the College of Arts and Sciences at Creighton University, born from Ignatian Sensibilities, and highlight the role of client engagement to engross students in a client-focused design process to deliver sustainable energy initiatives that become practically feasible with student leadership. For the senior capstone of this program, students engage in …


Software Defined Networks Based Smart Grid Communication: A Comprehensive Survey, Mubashir Husain Rehmani, Alan Davy, Brendan Jennings, Chadi Assi Jan 2019

Software Defined Networks Based Smart Grid Communication: A Comprehensive Survey, Mubashir Husain Rehmani, Alan Davy, Brendan Jennings, Chadi Assi

Publications

The current power grid is no longer a feasible solution due to ever-increasing user demand of electricity, old infrastructure, and reliability issues and thus require transformation to a better grid a.k.a., smart grid (SG). The key features that distinguish SG from the conventional electrical power grid are its capability to perform two-way communication, demand side management, and real time pricing. Despite all these advantages that SG will bring, there are certain issues which are specific to SG communication system. For instance, network management of current SG systems is complex, time consuming, and done manually. Moreover, SG communication (SGC) system is …


Nebraska Water Center Annual Report 2017-2018, The Nebraska Water Center Jan 2019

Nebraska Water Center Annual Report 2017-2018, The Nebraska Water Center

Nebraska Water Center: Administrative Materials

Contents

Introduction: Foreword • Director’s Letter by Chittaranjan Ray • Nebraska Water Center Overview and Timeline • Nebraska’s Top 10 Water Challenges

Research: Water Sciences Laboratory Overview • Nebraska Vadose Zone Program • Novel Nitrate Leaching Reduction • Ogallala Water Coordinated Agriculture Project (OWCAP) • Nebraska Water Productivity Report • USDA-NIFA Water End-User Grant • U.S. Geological Survey 104b Projects

Extension & Outreach: Bazile Groundwater Management Area • Platte River Basin Ecosystem Symposium • Testing Ag Performance Solutions (TAPS) • 2018 National Institutes for Water Resources Regional Symposium • Water Quality + Citizen Science • Nebraska Water and Natural Resources …


An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood Jan 2019

An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood

Electronic Theses and Dissertations

Nitrogen and phosphorus are often the limiting nutrients for marine and freshwater systems respectively. Additionally, stormwater often contains elevated levels of pathogens which can pollute the receiving water body and impact reuse applications [1-4]. The reduction of limiting nutrients and pathogens is a common primary target for stormwater best management practices (BMPs) [5]. Traditional BMPs, such as retention/detention treatment ponds require large footprints and may not be practical in ultra-urban environments where above ground space is limited. Upflow filters utilizing biosorption activated media (BAM) that can be placed underground offer a small footprint alternative. Additionally, BAM upflow filters can be …


Development Of Poly-Vinyl Alcohol Stabilized Silver Nanofluids For Solar Thermal Applications, James Walshe, George Amarandei, Hind Ahmed, Sarah Mccormack, John Doran Jan 2019

Development Of Poly-Vinyl Alcohol Stabilized Silver Nanofluids For Solar Thermal Applications, James Walshe, George Amarandei, Hind Ahmed, Sarah Mccormack, John Doran

Articles

Nanofluids offer the potential to address the low thermal conductivities found in conventional heat transfer fluids, through their unique electrical, optical and thermal properties, but their implementation remains restricted due to absorption and stability limitations. Here, we characterize and exploit the distinctive plasmonic properties exhibited by polyvinyl-alcohol stabilized silver nanostructures by tuning their absorption and thermal properties through controlling the nanoparticle size, morphology and particle-size distribution configuration at the synthesis stage. The photo-thermal efficiency of different water-based silver nanofluids under a standard AM1.5G weighted solar spectrum were explored, the influence of each of these components on the resulting fluids performance …


Stem And Sustainability: Creating Aviation Professional Change Agents, P. Clark, Doreen Mcgunagle, L. Zizka Jan 2019

Stem And Sustainability: Creating Aviation Professional Change Agents, P. Clark, Doreen Mcgunagle, L. Zizka

Publications

With the evolution of the workforce and the growing needs of the aviation industry, a clear need for concrete sustainability initiatives and actions have emerged. Sustainability in this sense becomes a matter of survival. For this reason, in this chapter, we will attempt to close three gaps in current sustainability studies: Theory vs practice, intention vs behavior, and education vs workplace.

Our purpose is to develop a ‘simple’ strategy for integrating all three pillars of sustainability into STEM HE programs that create authentic engagement and real buy-in from the students that are then replicated in the workplace. Based on the …


A Total Life Cycle Approach For Developing Predictive Design Methodologies To Optimize Product Performance, Buddhika M. Hapuwatte, Ibrahim S. Jawahir Jan 2019

A Total Life Cycle Approach For Developing Predictive Design Methodologies To Optimize Product Performance, Buddhika M. Hapuwatte, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainable products must be designed by considering how design decisions impact their total life cycle (TLC) sustainability content. Even more so important when designing products to incorporate the technological elements of sustainable manufacturing, the 6Rs (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacture), to achieve Circular Economy (CE). This paper presents the preliminary work of an ongoing research project on developing a novel framework incorporating predictive models with TLC considerations. This unique approach develops and integrates models with associated risks, and optimizes for maximizing the sustainability benefits due to design decisions. Such predictive capability is extremely useful for process planning, where …


Sustainable Production Through Balancing Trade-Offs Among Three Metrics In Flow Shop Scheduling, Amin Abedini, Wei Li, Fazleena Badurdeen, Ibrahim S. Jawahir Jan 2019

Sustainable Production Through Balancing Trade-Offs Among Three Metrics In Flow Shop Scheduling, Amin Abedini, Wei Li, Fazleena Badurdeen, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

In sustainable manufacturing, inconsistencies exist among objectives defined in triple-bottom-lines (TBL) of economy, society, and environment. Analogously, inconsistencies exist in flow shop scheduling among three objectives of minimizing total completion time (TCT), maximum completion time (MCT), and completion time variance (CTV), respectively. For continuous functions, the probability is zero to achieve the objectives at their optimal values, so is it at their worst values. Therefore, with inconsistencies among individual objectives of discrete functions, it is more meaningful and feasible to seek a solution with high probabilities that system performance varies within the …


Designing And Redesigning Products, Processes, And Systems For A Helical Economy, Ryan Bradley, Ibrahim S. Jawahir Jan 2019

Designing And Redesigning Products, Processes, And Systems For A Helical Economy, Ryan Bradley, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

The Circular Economy (CE) concept has promised to unlock trillions of dollars in business value while driving a significant reduction in the world’s resource consumption and anthropogenic emissions. However, CE mainly lives in ambiguity in the manufacturing domain because CE does not address the changes needed across all of the fundamental elements of manufacturing: products, processes, and systems. Conceptually, CE is grounded in the concept of closed-loop material flows that fit within ecological limits. This grounding translates into a steady state economy, a result that is not an option for the significant portion of the world living in poverty. Therefore, …


Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout Jan 2019

Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout

Electronic Theses and Dissertations

Disinfection byproducts (DBPs) presence in wastewater effluents and receiving waters may impact the quality of drinking water during water reuse practices. Natural solar photolysis is one of the biogeochemical processes that may lead to decreased DBPs concentrations in water. The purpose of this dissertation is to determine the fate of chlorinated, brominated and iodinated DBPs in surface water by natural sunlight photolysis and investigate the use of solar-based advanced oxidation processes (AOPs) for removal of DBPs in water. Total organic halogen (TOX) was used to measure total chlorinated- (TOCl), brominated- (TOBr) and iodinated-DBPs (TOI) in water. The first objective was …


Cadmium Sulfide-Buffered Pv Systems: Assessing The Environmental, Health, And Economic Impacts, Maqsood Ali Mughal, Rajesh Sharma Jan 2019

Cadmium Sulfide-Buffered Pv Systems: Assessing The Environmental, Health, And Economic Impacts, Maqsood Ali Mughal, Rajesh Sharma

Journal of the Arkansas Academy of Science

As the world’s population continues to grow, global energy crises are expected to rise in the future, thus accelerating the demand for renewable energy technology, particularly solar photovoltaics. The energy sector will face an increasingly complex array of interlocking challenges - technological, environmental, health, economic, and regulatory. In this paper, we study CdS, a widely used buffer material in thin film photovoltaics, to assess and monetize environmental, health, and socio-economic externalities associated with the use of the material. Currently, CdS has a significant advantage over other alternate buffer materials in terms of efficiency and low-cost production of large-area processing of …


Retention Strategies For Oil And Gas Industry Managers, Faye Gerard Jan 2019

Retention Strategies For Oil And Gas Industry Managers, Faye Gerard

Walden Dissertations and Doctoral Studies

The turnover cost of specialized employees in the oil and gas industry can exceed 400% of an employee's annual salary. The purpose of this multiple case study was to explore successful strategies that oil and gas company managers used to retain specialized employees. The specific population for the study was 8 managers from 4 oil and gas companies in a metropolitan city in the southern United States, which included 5 hiring managers and 3 engineering managers who had demonstrated success in retaining specialized employees. The conceptual lens used in this research study was the job embeddedness theory. Study data were …


Stream Flow Analysis Of The Big Sioux River Just South Of Brookings, South Dakota, Samuel Ruppert Jan 2019

Stream Flow Analysis Of The Big Sioux River Just South Of Brookings, South Dakota, Samuel Ruppert

Electronic Theses and Dissertations

Floods are the most common type of natural disaster in the world and one of the most damaging. Changes in climate conditions such as precipitation and temperature are causing changes in stream flow. This means that in order to better understand flooding and possibly develop a system for making flood predictions, stream flow needs to be analyzed more closely. The primary objective of this thesis is to analyze the Big Sioux River just south of Brookings, South Dakota, both annually and seasonally. The United States Geological Survey (USGS) has stream gauges placed in rivers and streams all over the United …


Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro Jan 2019

Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro

Wayne State University Dissertations

The work reported in this thesis focused on providing a fundamental understanding, at the molecular level, required to guide the effective design of electrocatalysts towards a superior reaction kinetics on the electrode of solid oxide electrolysis cells SOECs devices (SOECs) during the CO2 electrolysis. High temperature SOECs are electrochemical energy conversion technologies, that have emerged as promising alternatives to mitigate environmental issues associated with combustion-based technologies, such as the rising atmospheric CO2 levels. The conversion of excess CO2 into high-energy molecules, such as CO can be efficiently achieved through the use of SOEC – which facilitates the electrochemical reduction of …


Pawnee Dam Inflow Design Flood (Idf) Update And Stage-Frequency Curve Development Using Rmcrfa, Jennifer P. Christensen, Joshua J. Melliger Jan 2019

Pawnee Dam Inflow Design Flood (Idf) Update And Stage-Frequency Curve Development Using Rmcrfa, Jennifer P. Christensen, Joshua J. Melliger

United States Geological Survey: Water Reports and Publications

Pawnee Dam is one of the ten Salt Creek Dams designed and built in the 1960s to mitigate flooding in Lincoln, Nebraska. This short paper illustrates the update of the Pawnee Dam inflow design flood (IDF) through calibration to recent high flow events and the development of its stage-frequency or hydrologic loading curve with the U.S. Army Corps of Engineers’ Risk Management Center Reservoir Frequency Analysis (RMC-RFA) model. The IDF update follows Engineering Regulation 1110-8-2, Inflow Design Flood for Dams and Reservoirs, including unit hydrograph peaking and two antecedent pool elevations. Background information on the original design of the dam …


The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani Jan 2019

The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani

Electronic Theses and Dissertations

Many in-field and edge-of-field management practices have been used to reduce nutrient loads from agricultural fields. The denitrification woodchip bioreactor (WB) is one edgeof- field management practice that has proven to be effective in removing nitrate from subsurface drainage water. The success in nitrate removal achieved with WBs has raised interest in expanding their capabilities for removing other agricultural pollutants, including phosphorus, by using other types of media like phosphorus-sorbing filters or combining these filters with woodchips to remove both nitrate and phosphorus as dual-nutrient removal systems. Despite the extensive research done on WBs and nutrient filter materials, little consideration …


Programming Of Collaborative Robot (Cobot) To Selectively Disassemble Products To Obtain Critical Materials, Brittany Felder Jan 2019

Programming Of Collaborative Robot (Cobot) To Selectively Disassemble Products To Obtain Critical Materials, Brittany Felder

Research Opportunities for Engineering Undergraduates (ROEU) Program 2018-19

End-of-life products that contain critical materials, such as rare earth magnets, are often discarded even though there is remaining value that can be fed back into a remanufacturing process. This research aims to develop high throughput and economic value recovery from electric machines using collaborative robotics.


Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia Jan 2019

Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia

Open Access Theses & Dissertations

Steel industry is a major emitter of air pollutants, a leading industrial consumer of water, a minor source of contaminated liquids, a massive producer of solid waste, and a significant source of CO2. The objective on this thesis work is to minimize the greenhouse gas emissions when processing steel. Gears and bearings were evaluated based on their performance when exposed to cyclic stresses. The importance for having a proper set up on rolling mills to increase efficiency for processing rebar steel has been detailed on paper. In contrast, mechanical vibration has been measured on gears and bearings to determine efficiency …