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Full-Text Articles in Bioresource and Agricultural Engineering

Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer, Santiago Hoyos Echeverri May 2024

Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer, Santiago Hoyos Echeverri

Open Access Theses & Dissertations

Surface soil moisture retrieval from L-band brightness temperature has been developed for the past decades due to multiple beneficial characteristics of 1-2 GHz frequency bands for remote sensing of the environment. Numerous microwave emission models have been proposed for tower and satellite-based operations with successful retrieval of surface soil moisture and vegetation water content. As a result of the development of cost-effective and low-mass microwave L-band radiometers such as the Portable L-band Radiometer (PoLRa), surface soil moisture surveying traditionally developed by satellite missions SMOS and SMAP can now be developed at local scales, bringing these operations to commercial small unmanned …


Will Saf Turbocharge The Corn Ethanol Market?, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Miranda De Souza Almeida Mar 2024

Will Saf Turbocharge The Corn Ethanol Market?, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Miranda De Souza Almeida

Cornhusker Economics

The long-run outlook for the corn ethanol industry is questionable, due to a transition to electric and hybrid vehicles. One source of hope for the long run is the potential demand for producing Sustainable Aviation Fuel (SAF). SAF is a key component in the United States Aviation Climate Action Plan, a path to net-zero greenhouse gas (GHG) emissions in the aviation industry by 2050. Demand for ethanol for SAF offers hope to the ethanol industry, but it depends a great deal on policy decisions that are being made now. Here we sketch out this story.

Based on the information available …


Soil Nitrate Prediction Using Ftir-Atr, Vis-Nir, And Raman Spectroscopy, Sabiha Ferdous Mar 2024

Soil Nitrate Prediction Using Ftir-Atr, Vis-Nir, And Raman Spectroscopy, Sabiha Ferdous

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Fourier transform infrared spectroscopy (FTIR) combined with Attenuated total reflectance (ATR), Visible-Near Infrared spectroscopy (Vis-NIR), and Raman spectroscopy (RS) are non-destructive techniques for rapid determination of nitrogen compounds in soil. Leveraging FTIR-ATR and Vis-NIR spectra using partial least squares regression (PLSR) modeling, the study aims to predict soil nitrate content and explored the feasibility of Raman spectroscopy to detect nitrate (NO3-), nitrite (NO2-), and ammonium (NH4+) in soil. Soil samples were collected from four different fields, dried, sieved (2mm), and then used for collecting spectra (FTIR-ATR and Vis-NIR). Laboratory analysis was …


Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa Mar 2024

Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Long-term irrigation management research has been conducted from 2014 to 2023 for corn and soybean at the Eastern Nebraska Research, Extension, and Education Center (ENREEC) Variable Rate Irrigation (VRI) Field located in subhumid east-central Nebraska (in the Lower Platte North Natural Resources District). The objective of this report was to present the overall results from the VRI Field for 2021 to 2023. Across the three growing seasons, there were the following irrigation treatments: Best Management Practice (BMP), 50% BMP, 125% BMP, rainfed, Spatial ET Modeling Interface (SETMI), SDD1, SDD2, machine-learning-based Cyber-Physical System (CPS), a student team recommended rate, and industry …


An Automated On-The-Go Unloading System Reduces Harvest Operator Stress Relative To Manual Operation, Travis A. Burgers, Kusha Kamarei, Mukund Vora, Matthew Horne Jan 2024

An Automated On-The-Go Unloading System Reduces Harvest Operator Stress Relative To Manual Operation, Travis A. Burgers, Kusha Kamarei, Mukund Vora, Matthew Horne

Mechanical Engineering Faculty Publications

On-the-go unloading improves harvest operational efficiency, but it requires skilled labor because it is challenging and stressful to balance numerous concurrent tasks. Harvest automation reduces workload, stress, and fatigue. The objective of this study was to determine if using a commercially available, automated on-the-go unloading system (Raven Cart Automation TM , RCA, Raven Industries) would reduce operator stress com- pared to manual operation. Nine grain cart tractor operators and six combine operators participated in this study. Operators performed their typical harvest operation, except to alternate on-the-go unloading using RCA or operating manually. Skin conductance (elec- trodermal activity) was measured with …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise Dec 2023

Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise

Theses and Dissertations

The digenetic trematode, Bolbophorus damnificus, poses a substantial threat to catfish aquaculture, causing significant economic losses. Infestations lead to suppressed feed consumption, secondary bacterial infections and poor production performance. Survey data reveals widespread infestation in the in the southeastern United States. Current control strategies involve the application of a concentrated copper sulfate solution to reduce snail populations which serve as the first intermediate host of the trematode life cycle. This study aimed to improve treatment efficacy by developing a granular copper sulfate application system. A modified Gandy fertilizer applicator, equipped with a programmable control system, demonstrated accurate distribution of copper …


Aicropcam: Deploying Classification, Segmentation, Detection, And Counting Deep-Learning Models For Crop Monitoring On The Edge, Nipuna Chamara, Geng (Frank) Bai, Yufeng Ge Dec 2023

Aicropcam: Deploying Classification, Segmentation, Detection, And Counting Deep-Learning Models For Crop Monitoring On The Edge, Nipuna Chamara, Geng (Frank) Bai, Yufeng Ge

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Precision Agriculture (PA) promises to meet the future demands for food, feed, fiber, and fuel while keeping their production sustainable and environmentally friendly. PA relies heavily on sensing technologies to inform site-specific decision supports for planting, irrigation, fertilization, spraying, and harvesting. Traditional point-based sensors enjoy small data sizes but are limited in their capacity to measure plant and canopy parameters. On the other hand, imaging sensors can be powerful in measuring a wide range of these parameters, especially when coupled with Artificial Intelligence. The challenge, however, is the lack of computing, electric power, and connectivity infrastructure in agricultural fields, preventing …


Assessment Of Integrated Nutrient Management Practices On Soil Health And Nitrogen Efficiency In Cropping Systems, María José Oviedo Ventura Aug 2023

Assessment Of Integrated Nutrient Management Practices On Soil Health And Nitrogen Efficiency In Cropping Systems, María José Oviedo Ventura

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Groundwater quality in Nebraska is threatened by non-point source contributions of nitrate-nitrogen, primarily by agricultural systems. Intensive crop and livestock production that neglects the value of manure in crop fertility plans can contribute to soil degradation and natural resource impairment. The purpose of this study is to evaluate opportunities to improve agricultural nutrient management throughout Nebraska by quantifying opportunities for manure distribution, evaluating soil health implications of organic and inorganic soil amendments, and assessing nutrient management practices focused on reducing nitrate leaching in agricultural soils.

This study described in Chapter 2 provides a spatial illustration of nitrogen and phosphorus balances …


Improving Decision Support Systems With Machine Learning: Identifying Barriers To Adoption, Skye Brugler, Maaz Gardezi, Ali Dadkhah, Donna M. Rizzo, Asim Zia, Sharon A. Clay Jul 2023

Improving Decision Support Systems With Machine Learning: Identifying Barriers To Adoption, Skye Brugler, Maaz Gardezi, Ali Dadkhah, Donna M. Rizzo, Asim Zia, Sharon A. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Precision agriculture (PA) has been defined as a “management strategy that gathers, processes and analyzes temporal, spatial and individual data and combines it with other information to support management decisions according to estimated variability for improved resource use efficiency, productivity, quality, profitability and sustainability of agricultural production.” This definition suggests that because PA should simultaneously increase food production and reduce the environmental footprint, the barriers to adoption of PA should be explored. These barriers include: 1) the financial constraints associated with adopting DSS, 2) the hesitancy of farmers to change from their trusted advisor to a computer program often behaves …


Peer Review Of Teaching: Et Theory, Deficit Irrigation And Consumptive Use, Derek M. Heeren, Saleh Taghvaeian Jun 2023

Peer Review Of Teaching: Et Theory, Deficit Irrigation And Consumptive Use, Derek M. Heeren, Saleh Taghvaeian

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

A BSE Peer Review of Teaching was carried out for a graduate level course on Advanced Irrigation Management. This course has been offered for several years; each time improvements are made, but there is always a need for additional improvement. In particular, ET theory, deficit irrigation, and consumptive use are topics that the students struggle to grasp. These topics involve a relatively high level of math for an MS-level (800-level) Agricultural Systems Technology course, and the available materials on these topics either were not well developed or were not a good fit for this class. The primary objective was to …


Sample Article, Sample Author Jun 2023

Sample Article, Sample Author

Teknotan: Jurnal Industri Teknologi Pertanian

Abstract here.


Sample Article, Sample Author Jun 2023

Sample Article, Sample Author

Teknotan: Jurnal Industri Teknologi Pertanian

Abstract here.


Sample Article, Sample Author Jun 2023

Sample Article, Sample Author

Teknotan: Jurnal Industri Teknologi Pertanian

Abstract here.


Evaluation Of Conservation Practices Effect On Water Quality Using The Swat Model, Vivek Venishetty May 2023

Evaluation Of Conservation Practices Effect On Water Quality Using The Swat Model, Vivek Venishetty

Theses and Dissertations

The deterioration of water quality due to human-driven alternations has an adverse effect on the environment. More than 50% of surveyed surface water bodies in the United States (US) are classified as impaired waters as per the Clean Water Act. The pollutants affecting the water quality in the US are classified as point and non-point sources. Pollutant mitigation strategies such as the selective implementation of best management practices (BMPs) based on the severity of the pollution could improve water quality by reducing the amounts of pollutants. Quantifying the efficiency of a specific management practice can be difficult for large watersheds. …


Producer Long-Term Marketing Opportunities With Ethanol Plants, Austin Harthoorn, Logan Lloyd, Cory Walters, Kate Brooks May 2023

Producer Long-Term Marketing Opportunities With Ethanol Plants, Austin Harthoorn, Logan Lloyd, Cory Walters, Kate Brooks

Cornhusker Economics

Commodity marketing operates in a complex decision environment with constant information flow, which can conceal long-run financially profitable marketing opportunities for producers. In the corn marketing space, the competitive role of ethanol plants throughout the state may provide producers with long-run financial gains by strategically approaching marketing decisions. In this article, we characterize whether producers can gain financially from strategically marketing corn to ethanol plants. For example, do ethanol plants provide a better long-run return from pre-harvest hedging, spring sale, or harvest sale?

We investigate three important contracting times--forward contract for harvest delivery (called pre-harvest hereafter), harvest delivery, and spring …


A Deep-Learning Framework For Spray Pattern Segmentation And Estimation In Agricultural Spraying Systems, Praneel Acharya, Travis Burgers, Kim-Doang Nguyen May 2023

A Deep-Learning Framework For Spray Pattern Segmentation And Estimation In Agricultural Spraying Systems, Praneel Acharya, Travis Burgers, Kim-Doang Nguyen

Mechanical Engineering Faculty Publications

This work focuses on leveraging deep learning for agricultural applications, especially for spray pattern segmentation and spray cone angle estimation. These two characteristics are important to understanding the sprayer system such as nozzles used in agriculture. The core of this work includes three deep-learning convolution-based models. These models are trained and their performances are compared. After the best model is selected based on its performance, it is used for spray region segmentation and spray cone angle estimation. The output from the selected model provides a binary image representing the spray region. This binary image is further processed using image processing …


Irrigation-As-A-Service For Smallholder Farmers, Ishani Lal May 2023

Irrigation-As-A-Service For Smallholder Farmers, Ishani Lal

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

Irrigation is a crucial management practice that can help increase food security among smallholders globally while mitigating climate change impacts. High-efficiency irrigation technologies such as drip kits and sprinkler systems are relatively expensive and smallholder farmers cannot afford them to buffer crop yields against low precipitation. In many developing countries, farmers participate in robust informal markets for renting and sharing of irrigation equipment. Such services may be operated by farmers or via a third party such as irrigation start-ups, water user associations, non-governmental organizations, or even government agencies. These services are referred to collectively as Irrigation-as-a-Service (IaaS).

The objective of …


Case Study: Modeling A Grain Bin For Safe Entry Retrofit, Michael Dyer, Serap Gorucu, Randall Bock, Roderick Thomas, Jude Liu, Linda Fetzer Apr 2023

Case Study: Modeling A Grain Bin For Safe Entry Retrofit, Michael Dyer, Serap Gorucu, Randall Bock, Roderick Thomas, Jude Liu, Linda Fetzer

Office of Research Faculty and Staff Publications

All new grain bins produced after 2018 are recommended to have anchor points capable of handling a 2000 lb loading for attachment of bin entry lifeline systems. This study aims to assess the feasibility of a safe entry anchor point retrofit by using finite element analysis (FEA). We used a grain bin owned by Penn State for 3D FEA modeling in SolidWorks. To validate the model results from the FEA model, first strain and then deflection measurements were conducted on the grain. Strain gauges were applied to the grain bin in five locations and strain values were obtained after applying …


Deficit Irrigation Management For Irrigated Corn In Nebraska: Economically Viable?, Lia Nogueira, Cory Walters, Emily O'Donnell, E. Wesley F. Peterson, Suat Irmak Apr 2023

Deficit Irrigation Management For Irrigated Corn In Nebraska: Economically Viable?, Lia Nogueira, Cory Walters, Emily O'Donnell, E. Wesley F. Peterson, Suat Irmak

Cornhusker Economics

In this study we determine the economic value of deficit irrigation management using both technological and methodological advancements. The use of soil moisture probes represents the technological improvement. We provide improvements in the methodology as follows. Regarding data, we employ a field-size study, instead of plots, where the irrigation decision is determined by the moisture level in the soil measured through a soil moisture probe. Regarding the understanding of the yield response to water, although we examine the commonly used quadratic function, we improve upon this specification by also examining an alternative response function, the linear response stochastic plateau. Our …


The Next-Gen Crop Nutrient Stress Identification With High-Precision Sensing Technology In Digital Agriculture, Zhihang Song, Ziling Chen, Xing Wei, Jian Jin Mar 2023

The Next-Gen Crop Nutrient Stress Identification With High-Precision Sensing Technology In Digital Agriculture, Zhihang Song, Ziling Chen, Xing Wei, Jian Jin

Graduate Industrial Research Symposium

Crop yields are facing significant losses from nutrient deficiencies. Over-fertilizing also has negative economic and environmental impacts. It is challenging to optimize fertilizing without an accurate diagnosis. Recently, plant phenotyping has demonstrated outstanding capabilities in estimating crop traits. As one of the leading technologies, LeafSpec, provides high-quality crop image data for improving phenotyping quality. In this study, novel algorithms are developed for LeafSpec to identify crop nutrient deficiencies more accurately. Combined with UAV system, this technology will bring growers a robust solution for fertilizing diagnosis and scientific crop management.


The Impact Of Organized Activism On Technology Sharing, Ahmed Chennak, Amalia Yiannaka Jan 2023

The Impact Of Organized Activism On Technology Sharing, Ahmed Chennak, Amalia Yiannaka

Cornhusker Economics

What factors influence a firm's decision to share its technology with competitors? While patent licensing has received considerable attention in the literature, studies have typically focused on the optimal licensing contract for product and process innovations in various market settings. A key finding of this literature is that the optimal licensing strategy depends on the type of the patentee; that is, whether the patentee is a producer in the market (insider patentee) or not (outsider patentee). Little attention has been given, however, to the role the general public can play on firms' incentives to share their innovations through licensing contracts …


Role Of Social Network On Technology Adoption: Application To Nebraska Producers In The Face Of Undesirable Vegetation Transitions, Sabrina Gulab, Holly K. Nesbitt, Simanti Banerjee, Theresa Floyd, Karina A. Schoengold Jan 2023

Role Of Social Network On Technology Adoption: Application To Nebraska Producers In The Face Of Undesirable Vegetation Transitions, Sabrina Gulab, Holly K. Nesbitt, Simanti Banerjee, Theresa Floyd, Karina A. Schoengold

Cornhusker Economics

Conclusion

Producers need to have access to information regarding new conservation practices and technologies to ensure land management in the face of ecological threats in general and vegetation transitions (VTs) in the context of our study. This study investigates the role of an individual producer's social network on the willingness to seek information about technologies and management practices and the likelihood of new technology adoption with special attention to risk attitudes and producer spillover effects. Our results provide evidence that network composition and information obtained through a producer's social network don't influence an individual's willingness to seek information about new …


Clutch Analysis And Design For The Wildcat Pulling Team Quarter Scale Tractor Drivetrain, Lauren Doyle Jan 2023

Clutch Analysis And Design For The Wildcat Pulling Team Quarter Scale Tractor Drivetrain, Lauren Doyle

Lewis Honors College Thesis Collection

The University of Kentucky (UK) Wildcat Pulling Team competes in the annual ASABE International Quarter Scale Tractor Student Design Competition. In 2022 the team placed 3rd overall in the competition, missing 1st place by 23 points. The loss in points was due to the clutch subassembly having issues related to maneuverability, manufacturability, and serviceability. The goal of this project was to redesign the 2022 tractor’s drivetrain for the new 2023 competition tractor. Background research was conducted on three types of clutches: manual, electric, and centrifugal. The electric clutch and centrifugal clutch with manual override were tested to determine their viability …


Economic And Input-Use Efficiency Of Nitrogen Management Techniques In Non-Irrigated Maize Production, Katie J. Bathke Jan 2023

Economic And Input-Use Efficiency Of Nitrogen Management Techniques In Non-Irrigated Maize Production, Katie J. Bathke

Honors Program: Senior Projects (Public)

The efficiency of nitrogen (N) management has become a main concern in agricultural cropping systems for understanding the optimal N rate to help producers improve economically and reduce the exhaustion of natural resources environmentally. Nitrogen rates vary both temporally and spatially by the interactions of the soil environment and rainfall through a growing season. Thus, a site-specific approach can further optimize this variability with the understanding of the role soil variability plays in the N rate applied to a non-irrigated field. The objective of this study was to evaluate the various nitrogen treatments for their nutrient use efficiency and economic …


Assessing How Long-Term Conservation Agricultural Practices Impact Soil Properties And Soil, Water, And Nutrient Dynamics Through Soil Profile, Ajoy Kumar Saha Jan 2023

Assessing How Long-Term Conservation Agricultural Practices Impact Soil Properties And Soil, Water, And Nutrient Dynamics Through Soil Profile, Ajoy Kumar Saha

Electronic Theses and Dissertations

No abstract provided.


A Graduate-Level Field Course In Irrigation And Agricultural Water Management For An Immersive Learning Experience, Derek M. Heeren, László G. Hayde, Dean Eisenhauer, Peter G. Mccornick, Ali T. Mohammed, Aaron R. Mittelstet, Alan L. Boldt, Xin Qiao, David Mabie, Francisco Muñoz-Arriola Jan 2023

A Graduate-Level Field Course In Irrigation And Agricultural Water Management For An Immersive Learning Experience, Derek M. Heeren, László G. Hayde, Dean Eisenhauer, Peter G. Mccornick, Ali T. Mohammed, Aaron R. Mittelstet, Alan L. Boldt, Xin Qiao, David Mabie, Francisco Muñoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Effective irrigation and agricultural water management (IAWM) is critical for food security and water security. A key requirement in designing, implementing and operation of IWM is the necessary knowledge and capacity on the farm, in the service industry and within the supply chain. Educational opportunities that not only teach the relevant principles of irrigated agriculture, but also the necessary applied skills are essential. An Irrigation Field Course was initiated by the IHE Delft Institute for Water Education (IHE Delft) and was later developed as a joint field course with IHE Delft, the University of Nebraska-Lincoln (UNL), and the Daugherty Water …


Land Use/ Land Cover Change Patterns And Trends In Two Dryland Regions, Omar Sulaiman Belhaj Aug 2022

Land Use/ Land Cover Change Patterns And Trends In Two Dryland Regions, Omar Sulaiman Belhaj

Open Access Theses & Dissertations

Development and climate change affect the environment in numerous ways and to varyingdegrees. This effect appears prominent and more influential in arid regions. Therefore, land use/ land cover in these regions experience profound changes such as plant cover decrease and extinction of some plant species. Also, land use/ land cover in these regions has critical impacts on the environment and its components, such as shrublands shrinking and losing the habitat of animal species. The degree of changes and effects reaches severe levels that become urgent to figure out the impacts and find solutions to stop or mitigate the negative consequences. …


Vulnerable Vegetables And Efficient Fishers: A Study Of Primary Production Food Losses And Waste In Ireland, Tracey O'Connor, Rosanna Kleeman, Jennifer Attard Apr 2022

Vulnerable Vegetables And Efficient Fishers: A Study Of Primary Production Food Losses And Waste In Ireland, Tracey O'Connor, Rosanna Kleeman, Jennifer Attard

Publications

From 2022, the European Union Waste Framework Directive (WFD) requires member states to report annual food waste from each food supply chain stage. Comprehensive food losses and waste (FLW) data can be challenging to obtain for the primary production stage, i.e., farming and fishing. However, this information is vital in developing FLW mitigation actions appropriate to each country. This study describes the nature and extent of FLW from primary production in Ireland, using methods approved for WFD reporting. Causes of FLW and FLW as a proportion of total production were determined through interviews with Irish primary production stakeholders and using …


Vision And Radar Steering Reduces Agricultural Sprayer Operator Stress Without Compromising Steering Performance, Travis A. Burgers, Kelly J. Vanderwerff Jan 2022

Vision And Radar Steering Reduces Agricultural Sprayer Operator Stress Without Compromising Steering Performance, Travis A. Burgers, Kelly J. Vanderwerff

Mechanical Engineering Faculty Publications

Self-propelled agricultural sprayer operators work an average of 15 h d-1 in peak season, and steering is the task that causes the operator the most stress because of the large number of stimuli involved. Automatic guidance systems help reduce stress and fatigue for operators by allowing them to focus on tasks other than steering. Physiological signals like skin conductance (electrodermal activity, EDA) change with stress and can be used to identify stressful events. The objective of this study was to determine if using a commercially available vision and radar guidance system (VSN®, Raven Industries) reduces agricultural sprayer operators’ stress …