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Use Of The Soil-Plant-Air-Water Model To Predict Hydraulic Performance Of Vegetative Treatment Areas Controlling Open Lot Runoff, Daniel S. Andersen, Robert T. Burns, Lara B. Moody, Matthew J. Helmers, Robert Horton Jr., Carl H. Pederson 2010 Iowa State University

Use Of The Soil-Plant-Air-Water Model To Predict Hydraulic Performance Of Vegetative Treatment Areas Controlling Open Lot Runoff, Daniel S. Andersen, Robert T. Burns, Lara B. Moody, Matthew J. Helmers, Robert Horton Jr., Carl H. Pederson

Agricultural and Biosystems Engineering Publications

Alternative treatment systems to control runoff from open beef feedlots may enhance environmental security and protect water quality. Several Midwestern states have issued National Pollution Discharge Elimination System permits allowing beef feedlots to use vegetative treatment systems (VTSs) to control and treat feedlot runoff. Monitoring VTSs has provided data to validate performance modeling strategies. The objective of this study was to evaluate the ability of the Soil-Plant-Air-Water (SPAW) model to predict the hydraulic performance of vegetative treatment areas (VTAs). Two approaches, one using the field module and the other the pond module of the SPAW model, were investigated. The model ...


Laboratory Scale Evaluation Of Volatile Organic Compound Emissions As Indication Of Swine Carcass Degradation Inside Biosecure Composting Units, Neslihan Akdeniz, Jacek A. Koziel, Hee-Kwon Ahn, Thomas D. Glanville, Benjamin P. Crawford, D. Raj Raman 2010 Iowa State University

Laboratory Scale Evaluation Of Volatile Organic Compound Emissions As Indication Of Swine Carcass Degradation Inside Biosecure Composting Units, Neslihan Akdeniz, Jacek A. Koziel, Hee-Kwon Ahn, Thomas D. Glanville, Benjamin P. Crawford, D. Raj Raman

Agricultural and Biosystems Engineering Publications

Biosecure livestock mortality composting systems have been used to dispose of diseased livestock mortalities. In those types of system, visual inspection of carcass degradation is not possible and monitoring VOCs (volatile organic compounds) released by carcasses is a new approach to assess progress of the composting process. In this study, field-scale livestock mortality composting systems were simulated and a laboratory scale composting system with aerobic and anaerobic test units was designed to collect VOC samples from the headspace of decaying plant materials (70 g dry weight) and swine tissues (70 g dry weight) at controlled operating temperatures. Headspace samples were ...


Real-Time Pressure And Flow Dynamics Due To Boom Section And Individual Nozzle Control On Agricultural Sprayers, Ajay Sharda, John P. Fulton, Timothy P. McDonald, Wesley C. Zech, Matthew J. Darr, Christian J. Brodbeck 2010 Auburn University

Real-Time Pressure And Flow Dynamics Due To Boom Section And Individual Nozzle Control On Agricultural Sprayers, Ajay Sharda, John P. Fulton, Timothy P. Mcdonald, Wesley C. Zech, Matthew J. Darr, Christian J. Brodbeck

Agricultural and Biosystems Engineering Publications

Most modern spray controllers when coupled with a differential global positioning system (DGPS) receiver can provide automatic section or swath (boom section or nozzle) control capabilities that minimize overlap and application into undesirable areas. This technology can improve application accuracy of pesticides and fertilizers, thereby reducing the number of inputs while promoting environmental stewardship. However, dynamic system response for sprayer boom operation, which includes cycling or using auto-swath technology, has not been investigated. Therefore, a study was conducted to develop a methodology and subsequently perform experiments to evaluate tip pressure and system flow variations on a typical agricultural sprayer equipped ...


Prediction Of Indoor Climate And Long-Term Air Quality Using The Bta-Aqp Model: Part Ii. Overall Model Evaluation And Application, Gang Sun, Steven J. Hoff 2010 Iowa State University

Prediction Of Indoor Climate And Long-Term Air Quality Using The Bta-Aqp Model: Part Ii. Overall Model Evaluation And Application, Gang Sun, Steven J. Hoff

Agricultural and Biosystems Engineering Publications

The objective of this research was to develop a building thermal analysis and air quality predictive (BTA-AQP) model to predict indoor climate and long-term air quality (NH3, H2S, and CO2 concentrations and emissions) for swine deep-pit buildings. This article presents part II of this research, in which the performance of the BTA-AQP model is evaluated using typical meteorological year (TMY3) data in predicting long-term air quality trends. The good model performance ratings (MAE/SD < 0.5, CRM ˜ 0; IoA ˜ 1; and NSEF > 0.5 for all the predicted parameters) and the graphical presentations reveal that the BTA-AQP model was able to accurately forecast indoor climate and gas concentrations ...


Using Spatial Uncertainty Of Prior Measurements To Design Adaptive Sampling Of Elevation Data, Samsuzana Abd Aziz, Brian L. Steward, Manoj Karkee 2010 Universiti Putra Malaysia

Using Spatial Uncertainty Of Prior Measurements To Design Adaptive Sampling Of Elevation Data, Samsuzana Abd Aziz, Brian L. Steward, Manoj Karkee

Agricultural and Biosystems Engineering Publications

Field sampling can be a major expense for planning within-field management in precision agriculture. An efficient sampling strategy should address knowledge gaps, rather than exhaustively collect redundant data. Modification of existing schemes is possible by incorporating prior knowledge of spatial patterns within the field. In this study, spatial uncertainty of prior digital elevation model (DEM) estimates was used to locate adaptive re-survey regions in the field. An agricultural vehicle equipped with RTK-DGPS was driven across a 2.3 ha field area to measure the field elevation in a continuous fashion. A geostatistical simulation technique was used to simulate field DEMs ...


Evaluation Of Ultrasonic Pretreatment On Anaerobic Digestion Of Different Animal Manures, Wei Wu-haan, Robert T. Burns, Lara B. Moody, David A. Grewell, D. Raj Raman 2010 Iowa State University

Evaluation Of Ultrasonic Pretreatment On Anaerobic Digestion Of Different Animal Manures, Wei Wu-Haan, Robert T. Burns, Lara B. Moody, David A. Grewell, D. Raj Raman

Agricultural and Biosystems Engineering Publications

This article addresses the effect of ultrasonication as a pretreatment to anaerobic digestion of four types of animal manure, including swine slurry, beef feedlot manure, dairy manure slurry, and separated dairy manure effluent. The effect of ultrasonication on soluble chemical oxygen demand (SCOD) and biochemical methane potential (BMP) were determined, and the energy efficiency of ultrasonic pretreatment was evaluated. Ultrasonic pretreatment was applied at two amplitudes (80 and 160 µmpp) and at two time settings (15 and 30 s) to each of the four manure types. The SCOD of each manure sample was determined before and after ultrasonic pretreatment. In ...


Characterization Of Two Types Of Covered Creep Boxes For Piglet Usage And Piglet Performance In A Naturally Ventilated Swine Farrowing Building, Zhao Bing Gu, Hongwei Xin, Chaoyuan Wang, Zhengxiang Shi, Wei Cao, Zuohua Liu, Baoming Li 2010 Chongqing Academy of Animal Sciences

Characterization Of Two Types Of Covered Creep Boxes For Piglet Usage And Piglet Performance In A Naturally Ventilated Swine Farrowing Building, Zhao Bing Gu, Hongwei Xin, Chaoyuan Wang, Zhengxiang Shi, Wei Cao, Zuohua Liu, Baoming Li

Agricultural and Biosystems Engineering Publications

This study investigates two types of covered piglet creep boxes in a naturally ventilated swine farrowing building with regards to air quality (ammonia and carbon dioxide levels), piglet usage of the box, and piglet health and performance. The covered creep boxes featured either double plastic curtains along the entire width of the box (designated as the DC box) or an arc-shaped access opening occupying about one-third of the box width (designated as the AO box). The study was conducted with 12 farrowing crates, six per box regimen, during wintertime. Continuous, 24-h video observations of the piglet behaviors were made at ...


Lab-Scale Assessment Of Gaseous Emissions From Laying-Hen Manure Storage As Affected By Physical And Environmental Factors, Hong Li, Hongwei Xin 2010 Iowa State University

Lab-Scale Assessment Of Gaseous Emissions From Laying-Hen Manure Storage As Affected By Physical And Environmental Factors, Hong Li, Hongwei Xin

Agricultural and Biosystems Engineering Publications

Manure-belt (MB) and high-rise (HR) laying-hen houses are the two predominant housing types in the U.S. Compared with HR houses, MB houses have better indoor air quality and lower aerial emissions as a result of frequent (every 1 to 4 d) manure removal from the hen houses into separate manure storage. However, emissions from on-farm manure storage are integral parts of the whole-farm emissions and need to be quantified. This series of lab-scale studies assesses emission rates (ER) of ammonia (NH3) and greenhouse gases (CH4, CO2, and N2O) from stored laying-hen manure as affected by the following physical and ...


Comparison Of The Iowa State University Effluent Limitation Guidelines Model With The Soil-Plant-Air-Water Model For Evaluating Containment Basin Performance, Daniel S. Andersen, Robert T. Burns, Lara B. Moody, Matthew J. Helmers, Robert Horton Jr. 2010 Iowa State University

Comparison Of The Iowa State University Effluent Limitation Guidelines Model With The Soil-Plant-Air-Water Model For Evaluating Containment Basin Performance, Daniel S. Andersen, Robert T. Burns, Lara B. Moody, Matthew J. Helmers, Robert Horton Jr.

Agricultural and Biosystems Engineering Publications

This article compares results from the Iowa State University Effluent Limitations Guidelines (ISU-ELG) model to results obtained using the Soil-Plant-Air-Water (SPAW) model to simulate feedlot runoff containment basin overflow volume. The objective was to verify that the ISU-ELG model was providing a reasonable prediction of basin overflow. The ISU-ELG model uses a set of guidelines to determine if land application is acceptable, whereas the SPAW model uses a soil moisture criterion. The criterion for determining if a particular day was suitable for land application of basin effluent was investigated to determine the effect on basin overflow volumes. The results show ...


Technical Note: Hydraulic Property Determination Of Denitrifying Bioreactor Fill Media, Laura E. Christianson, Adrià Castelló, Reid D. Christianson, Matthew J. Helmers, Alok Bhandari 2010 Iowa State University

Technical Note: Hydraulic Property Determination Of Denitrifying Bioreactor Fill Media, Laura E. Christianson, Adrià Castelló, Reid D. Christianson, Matthew J. Helmers, Alok Bhandari

Agricultural and Biosystems Engineering Publications

Denitrification bioreactors are one of the newest options for nitrate removal in agricultural drainage waters. Optimization of denitrification bioreactor design requires the ability to identify concrete values for the hydraulic properties of bioreactor fill media. Hydraulic properties, chiefly saturated hydraulic conductivity but also porosity and particle size, are not known for many types of possible bioreactor media though they have a significant impact upon bioreactor design and performance. This work was undertaken to more fully quantify the hydraulic properties of the major type of fill media used in Iowa denitrification bioreactors through a series of porosity, hydraulic conductivity, and particle ...


Effect Of Ultrasonic Pretreatment On Methane Production Potential From Corn Ethanol Coproducts, Wei Wu-Haan, Robert T. Burns, Lara B. Moody, Cody John Hearn, David A. Grewell 2010 Iowa State University

Effect Of Ultrasonic Pretreatment On Methane Production Potential From Corn Ethanol Coproducts, Wei Wu-Haan, Robert T. Burns, Lara B. Moody, Cody John Hearn, David A. Grewell

Agricultural and Biosystems Engineering Publications

This article addresses the biochemical methane potential (BMP) production from anaerobic digestion of corn-ethanol coproducts including dried distiller grain with solubles (DDGS), distiller's wet grains (DWG), thin stillage, and condensed distiller's solubles (CDS) as well as evaluating the effects of ultrasonic pretreatment on methane production from these feedstocks. Ultrasonic pretreatment was applied with three amplitude settings of 33% (52.8 µmpp), 66% (105.6 µmpp), and 100% (160 µmpp) as well as five time settings (10, 20, 30, 40, and 50 s) to each of the four coproducts prior to conducting benchtop BMP trials. Ultrasonic pretreatment reduced mean ...


Optimal Coverage Path Planning For Arable Farming On 2d Surfaces, Jian Jin, Lie Tang 2010 Iowa State University

Optimal Coverage Path Planning For Arable Farming On 2d Surfaces, Jian Jin, Lie Tang

Agricultural and Biosystems Engineering Publications

With the rapid adoption of automatic guidance systems in agriculture, automated path planning has great potential to further optimize field operations. Field operations should be done in a manner that minimizes time and travel over field surfaces and should be coordinated with specific field operation requirements, machine characteristics, and topographical features of arable lands. To reach this goal, an intelligent coverage path planning algorithm is the key. To determine the full coverage pattern of a given field by using boustrophedon paths, it is necessary to know whether to and how to decompose a field into sub-regions and how to determine ...


Prediction Of Indoor Climate And Long-Term Air Quality Using The Bta-Aqp Model: Part I. Bta Model Development And Evaluation, Gang Sun, Steven J. Hoff 2010 Iowa State University

Prediction Of Indoor Climate And Long-Term Air Quality Using The Bta-Aqp Model: Part I. Bta Model Development And Evaluation, Gang Sun, Steven J. Hoff

Agricultural and Biosystems Engineering Publications

The objective of this research was to develop a building thermal analysis and air quality predictive (BTA-AQP) model to predict ventilation rate, indoor temperature, and long-term air quality (NH3, H2S, and CO2 concentrations and emissions) for swine deep-pit buildings. This article, part I of II, presents a lumped capacitance model (BTA model) to predict the transient behavior of ventilation rate and indoor air temperature according to the thermo-physical properties of a typical swine building, setpoint temperature scheme, fan staging scheme, transient outside temperature, and the heat fluxes from pigs and supplemental heaters. The obtained ventilation rate and resulting indoor air ...


Detection And Identification Of Microorganisms In Mixed Cultures By Nanoparticle-Induced Nanospr Enhanced Ftir Spectroscopy And Chemometrics, Qi Wang, Nan Xiao, Chenxu Yu 2010 Iowa State University

Detection And Identification Of Microorganisms In Mixed Cultures By Nanoparticle-Induced Nanospr Enhanced Ftir Spectroscopy And Chemometrics, Qi Wang, Nan Xiao, Chenxu Yu

Agricultural and Biosystems Engineering Publications

Routine identification of pathogenic microorganisms predominantly based on nutritional and biochemical tests is a time-consuming process, but delay may lead to fatal consequences at times. In this work, nanoparticle-induced nanoSPR enhanced IR spectroscopy was used in conjunction with a background elimination data processing algorithm to directly identify microorganisms in mixed cultures. It was demonstrated that the microbial composition of mixtures of different E. coli strains could be accurately identified using our method, at a concentration level of 103 CFU mL-1. The procedure was also applied to determine the presence or absence of pathogenic microorganisms in a simple but real food ...


Islands And Holes As Measures Of Mass Balance In Growth Of The (√3×√3)R30° Phase Of Ag On Si(111), Alex Belianinov, Barış Ünal, Ning Lu, Min Ji, Kai-Ming Ho, Cai-Zhuang Wang, Michael C. Tringides, Patricia A. Thiel 2010 Iowa State University

Islands And Holes As Measures Of Mass Balance In Growth Of The (√3×√3)R30° Phase Of Ag On Si(111), Alex Belianinov, Barış Ünal, Ning Lu, Min Ji, Kai-Ming Ho, Cai-Zhuang Wang, Michael C. Tringides, Patricia A. Thiel

Chemistry Publications

It is well known that conversion of Si(111)-(7×7) into the (√3×√3)R30° phase of adsorbed Ag requires a change in the Si density, and causes formation of islands and holes at the surface. By mass balance, the ratio of areas of islands and holes (RIH) should be approximately 1. However, we find that the ratio is significantly higher, depending on preparation conditions. A possible explanation would be that there are different types of (√3×√3)R30° structures. However, neither scanning tunneling microscopy nor density-functional theory (implemented as a genetic algorithm search) supports this explanation. We ...


Soil Loading Effects Of Planter Depth-Gauge Wheels On Early Corn Growth, H. Mark Hanna, Brian L. Steward, Landon Aldinger 2010 Iowa State University

Soil Loading Effects Of Planter Depth-Gauge Wheels On Early Corn Growth, H. Mark Hanna, Brian L. Steward, Landon Aldinger

Agricultural and Biosystems Engineering Publications

Final soil manipulation before seed germination occurs during the planting operation. Contact force of depth-gauge wheels adjacent to the seed opener potentially alters the environment for corn seed germination and early plant growth. A field experiment was conducted measuring seed spacing, spacing variability, seed depth, emergence rate, plant dry matter, final stand, crop growth stage, and extended leaf height with different soil contact loads [light, 180 to 490 N (40 to 110 lb); medium, 490 to 890 N (110 to 200 lb); and heavy, over 890 N (200 lb)] and a range of three soil moistures (dry, moist, wet). A ...


Effect Of Ammonia Soaking Pretreatment And Enzyme Addition On Biochemical Methane Potential Of Switchgrass, Jennifer Nicole Himmelsbach, D. Raj Raman, Robert P. Anex, Robert T. Burns, Carol Rose Faulhaber 2010 Iowa State University

Effect Of Ammonia Soaking Pretreatment And Enzyme Addition On Biochemical Methane Potential Of Switchgrass, Jennifer Nicole Himmelsbach, D. Raj Raman, Robert P. Anex, Robert T. Burns, Carol Rose Faulhaber

Agricultural and Biosystems Engineering Publications

This article presents the biochemical methane potential (BMP) results from the anaerobic digestion (AD) of switchgrass. Triplicate BMP assays were performed on: untreated switchgrass, aqueous ammonia soaking (AAS) pretreated switchgrass (soaked in 29.5% reagent-grade aqueous ammonia at 5 L kg-1 switchgrass for 5 d), and AAS-pretreated switchgrass plus cellulytic enzymes at 12.5, 25, 62.5, and 125 filter paper units (FPU) enzyme g-1 volatile solids (VS). Biogas production and biogas methane content were measured daily in all treatments for 21 d. Both biogas and corrected methane production varied significantly among treatments, especially during the first 7 d of ...


Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff 2010 Iowa State University

Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff

Agricultural and Biosystems Engineering Publications

The community assessment model (CAM) for odor dispersion is a tool to assist in the siting of swine production facilities. CAM considers the size and type of a swine production system, local historical weather conditions, and odor control implementation. It predicts the number of hours of exposure to various levels of odor, by month, for each receptor in a given community. A follow-up survey of all CAM users since 2005 was conducted. The survey was designed to provide: 1) formative feedback for programming adjustments to improve Extension efficiency, usability, and reduce costs; and 2) summative feedback used to provide an ...


Livestock Grazing And Vegetative Filter Strip Buffer Effects On Runoff Sediment, Nitrate, And Phosphorus Losses, David F. Webber, Steven K. Mickelson, Syed I. Ahmed, James R. Russell, Wendy J. Powers, Richard C. Schultz, John Kovar 2010 Iowa State University

Livestock Grazing And Vegetative Filter Strip Buffer Effects On Runoff Sediment, Nitrate, And Phosphorus Losses, David F. Webber, Steven K. Mickelson, Syed I. Ahmed, James R. Russell, Wendy J. Powers, Richard C. Schultz, John Kovar

Agricultural and Biosystems Engineering Publications

Livestock grazing in the Midwestern United States can result in significant levels of runoff sediment and nutrient losses to surface water resources. Some of these contaminants can increase stream eutrophication and are suspected of contributing to hypoxic conditions in the Gulf of Mexico. This research quantified effects of livestock grazing management practices and vegetative filter strip buffers on runoff depth and mass losses of total solids, nitrate-nitrogen (NO3-N), and ortho-phosphorus (PO4-P) under natural hydrologic conditions. Runoff data were collected from 12 rainfall events during 2001 to 2003 at an Iowa State University research farm in central ...


Hydrologic Modeling Of Runoff From A Livestock Manure Windrow Composting Site With A Fly Ash Pad Surface And Vegetative Filter Strip Buffers, David F. Webber, Steven K. Mickelson, Larry W. Wulf, Thomas L. Richard, Heekwon Ahn 2010 Iowa State University

Hydrologic Modeling Of Runoff From A Livestock Manure Windrow Composting Site With A Fly Ash Pad Surface And Vegetative Filter Strip Buffers, David F. Webber, Steven K. Mickelson, Larry W. Wulf, Thomas L. Richard, Heekwon Ahn

Agricultural and Biosystems Engineering Publications

Windrow composting of livestock manure materials provides a strategy for converting organic wastes into a recyclable soil fertility product that is less hazardous to the environment. Although outdoor windrow composting can produce runoff that is detrimental to surface water quality, vegetative filter strip (VFS) buffers were reported to significantly reduce runoff and contaminants from a windrow composting research site. To estimate the efficacy of VFS buffers and other best management practices on runoff from future windrow composting facilities, a computer hydrologic model may provide a valuable tool for predicting runoff losses from these proposed sites. This research evaluated a windrow ...


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