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Bioresource and Agricultural Engineering

Agricultural and Biosystems Engineering Publications

Articles 1 - 7 of 7

Full-Text Articles in Life Sciences

Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2012

Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

This paper compares energy use for different pig production systems in Iowa, a leader in US swine production. Pig production systems include not only the growth and performance of the pigs, but also the supporting infrastructure of pig production. This supporting infrastructure includes swine housing, facility management, feedstuff provision, swine diets, and manure management. Six different facility type × diet formulation × cropping sequence scenarios were modeled and compared. The baseline system examined produces 15,600 pigs annually using confinement facilities and a corn-soybean cropping sequence. Diet formulations for the baseline system were corn-soybean meal diets that included the synthetic AA L-lysine ...


An Engineering-Economic Model For Analyzing Dairy Plug-Flow Anaerobic Digesters: Cost Structures And Policy Implications, Carol Rose Faulhaber, D. Raj Raman, Robert Burns Jan 2012

An Engineering-Economic Model For Analyzing Dairy Plug-Flow Anaerobic Digesters: Cost Structures And Policy Implications, Carol Rose Faulhaber, D. Raj Raman, Robert Burns

Agricultural and Biosystems Engineering Publications

Treating animal wastes through anaerobic digestion (AD) yields methane-rich biogas that can be used for power generation or heating, and a nutrient-rich digestate that can be land-applied as fertilizer. Furthermore, AD reduces odors from stored and land-applied manures. Despite these benefits, AD deployment rates in the U.S. are only 5% for dairy farms identified as suitable for AD by the U.S. Environmental Protection Agency. The objective of this study was to analyze the economic and technical limitations of farm-scale anaerobic digesters using a simple model permitting insight into the fundamental constraints on the technology. A model was developed ...


Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2010

Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

Demand for nonsolar energy and concern about the implications of fossil fuel combustion have encouraged examination of energy use associated with agriculture. The United States is a global leader in pig production, and the United States swine industry is centered in Iowa. Feed is the largest individual input in pig production, but the energy consumption of the Iowa swine feed production chain has yet to be critically examined. This analysis examines nonsolar energy use and resulting 100-yr global warming potential (GWP) associated with the swine feed production chain, beginning with cultivation of crops and concluding with diet formulation. The nonsolar ...


Simulating The Effects Of Spatially Variable Irrigation On Corn Yields, Costs, And Revenue In Iowa, Kendall C. Dejonge, Amy L. Kaleita, Kelly R. Thorp Aug 2007

Simulating The Effects Of Spatially Variable Irrigation On Corn Yields, Costs, And Revenue In Iowa, Kendall C. Dejonge, Amy L. Kaleita, Kelly R. Thorp

Agricultural and Biosystems Engineering Publications

In this study, the CERES-Maize crop model was used in conjunction with Apollo, a shell program, to evaluate potential improved yield in a central Iowa cornfield on a spatially and temporally variable basis. Five years of historical yield and weather data were used to calibrate the model over 100 spatially variable grid cells for non-irrigated conditions in the 20.25 ha field. This calibrated model then used 28 years of historical weather data to simulate three irrigation scenarios: no irrigation, scheduled uniform irrigation, and precision irrigation. Irrigation improved yield by at least 500 kg ha−1 in half of the ...


Combine Harvester Econometric Model With Forward Speed Optimization, Nathan E. Isaac, Graeme R. Quick, Stuart J. Birrell, William M. Edwards, Bruce A. Coers Jan 2006

Combine Harvester Econometric Model With Forward Speed Optimization, Nathan E. Isaac, Graeme R. Quick, Stuart J. Birrell, William M. Edwards, Bruce A. Coers

Agricultural and Biosystems Engineering Publications

A combine harvester econometric simulation model was developed with the goal of matching the combine forward speed to the maximum harvested net income per acre. The model considers the machinery management costs of owning a combine and platform header for harvesting wheat. A statistical Design of Experiment (DOE) was used to evaluate the model using tri-level variables; the medium values constituted the model base case. Of the 27 input variables, the optimum speed was significantly influenced by the crop area, G/MOG ratio, grain unit price, field yield, field efficiency, grain moisture content, probability of a working day in the ...


Comparison Of Different Styles Of Swine Finishing Facilities Within A Uniform Production System, David R. Stender, Jay D. Harmon, Jerry D. Weiss, Darci Cox Jan 2003

Comparison Of Different Styles Of Swine Finishing Facilities Within A Uniform Production System, David R. Stender, Jay D. Harmon, Jerry D. Weiss, Darci Cox

Agricultural and Biosystems Engineering Publications

Swine originating from one farrowing and nursery source were grown in five different finishing facility types. Three of the facilities were considered contemporary styles and two facilities were based on older technologies. The total data set included information collected on 46,408 pigs from 25 groups. The three contemporary facility styles included a fully slatted, hybrid ventilated facility; a fully slatted tunnel ventilated facility; and a partially slatted naturally ventilated facility. These newer facilities were compared to an older, less environmentally controlled facility and an outdoor feeding lot. No significant differences were observed in production performance of the three styles ...


A Spatial Decision Support System For Livestock Production Planning And Environmental Management, Dharmesh K. Jain, U. Sunday Tim, Robert W. Jolly Jan 1995

A Spatial Decision Support System For Livestock Production Planning And Environmental Management, Dharmesh K. Jain, U. Sunday Tim, Robert W. Jolly

Agricultural and Biosystems Engineering Publications

Spatial decision support systems are used to plan production systems and direct the implementation management strategies that are compatible with environmental protection goals. They enable resource managers to select appropriate production technologies that minimize environmental damage, and evaluate alternative management practices. This article describes a spatial decision support system (SDSS) developed to facilitate planning and management of environmentally sound livestock production. The SDSS integrates a geographic information system, spatial and biophysical modeling, and a knowledge-based system into an interactive tool to select suitable watershed land areas for siting livestock production, to select fields for manure application, and to determine the ...