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Selected Works

2015

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Articles 31 - 60 of 2105

Full-Text Articles in Engineering

Characteristics Of Power Quality Disturbance Levels In Australia, Sean Elphick, Vic Smith, Vic Gosbell, Robert Barr Dec 2015

Characteristics Of Power Quality Disturbance Levels In Australia, Sean Elphick, Vic Smith, Vic Gosbell, Robert Barr

Robert Barr

The Australian Long Term Power Quality Survey (LTNPQS) now covers 2,000 sites with a range of different characteristics including strength (related to fault level), line construction and dominant load type. This paper details the latest outcomes of the LTNPQS project in terms of both disturbance levels and reporting methods. A comparison of the differences between voltage, unbalance and harmonic THD levels at strong (close to transformer) and weak (towards the end of LV feeders) sites has been performed and significant differences have been found. A multivariable linear regression study has been undertaken in order to investigate the correlation between site …

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Modelling And Simulation Of The Magnetically Impelled Arc Butt (Miab) Process For Transmission Pipeline Applications, John Norrish, Dominic Cuiuri, Mohammad Hossain Dec 2015

Modelling And Simulation Of The Magnetically Impelled Arc Butt (Miab) Process For Transmission Pipeline Applications, John Norrish, Dominic Cuiuri, Mohammad Hossain

Dominic Cuiuri

Early patents for the Magnetically Impelled Arc Butt process (MIAB) date back to 1940 [1] and the basic principles of the process have remained unchanged from this time. The process was however refined in the 1970s for use in the production of automotive components and has been used extensively in this area. Investigation of the process for pipe girth welding have been reported and commercial pipe welding heads are reported to be available in the Ukraine [2], Although the process is well established it is believed that a more fundamental analysis of the mechanisms involved would assist in the optimisation …

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Disorder-Induced Depression Of The Curie Temperature In Mechanically Milled Gdal2, Marco Morales Torres, D. Williams, Paul Shand, C. Stark, Thomas Pekarek, L. Yue, Valeri Petkov, Diandra Leslie-Pelecky Dec 2015

Disorder-Induced Depression Of The Curie Temperature In Mechanically Milled Gdal2, Marco Morales Torres, D. Williams, Paul Shand, C. Stark, Thomas Pekarek, L. Yue, Valeri Petkov, Diandra Leslie-Pelecky

Thomas M. Pekarek

The effect of disorder on the ferromagnetic transition is investigated in mechanically milled GdAl2. GdAl2is a ferromagnet when crystalline and a spin glass when amorphous. Mechanical milling progressively disorders the alloy, allowing observation of the change from ferromagnetic to a disordered magnetic state. X-ray diffraction and pair-distribution-function analysis are used to determine the grain size, lattice parameter, and mean-squared atomic displacements. The magnetization as a function of temperature is described by a Gaussian distribution of Curie temperatures. The mean Curie temperature decreases with decreasing lattice parameter, where lattice parameter serves as a measure of defect concentration. Two different rates of …

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Investigation On Welding Arc Interruptions In The Presence Of Magnetic Fields: Welding Current Influence, Ruham Reis, Americo Scotti, John Norrish, Dominic Cuiuri Dec 2015

Investigation On Welding Arc Interruptions In The Presence Of Magnetic Fields: Welding Current Influence, Ruham Reis, Americo Scotti, John Norrish, Dominic Cuiuri

Dominic Cuiuri

Arc interruptions and, therefore, oscillation in the amount of energy and molten wire delivered to the plate have been observed during tandem pulsed gas metal arc welding (GMAW). It appears that these instabilities are related to the magnetic interaction between the arcs. In order to clarify the possible mechanisms involved, this paper tries to mimic the tandem GMAW arc interruptions. External magnetic fields were dynamically applied to GTAW arcs in constant current mode to verify their resistance to extinction as a function of current level and direction of deflection. High-speed filming was carried out as an additional tool to understand …

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A Case Study: Data Management In Biomedical Engineering, Glenn Gaudette, Donna Kafel Dec 2015

A Case Study: Data Management In Biomedical Engineering, Glenn Gaudette, Donna Kafel

Glenn R. Gaudette

In a biomedical engineering lab at Worcester Polytechnic Institute, co-author Dr. Glenn R. Gaudette and his research team are investigating the effects of stem cell therapy on the regeneration of function in damaged cardiac tissue in laboratory rats. Each instance of stem cell experimentation on a rat yields hundreds of data sets that must be carefully captured, documented and securely stored so that the data will be easily accessed and retrieved for papers, reports, further research, and validation of findings, while meeting NIH guidelines for data sharing. After a brief introduction to the bioengineering field and stem cell research, this …

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Characterization Of Ten Channel Electro-Optic Phase Modulator And Amplifier In Algaas/Gaas, David Brown Dec 2015

Characterization Of Ten Channel Electro-Optic Phase Modulator And Amplifier In Algaas/Gaas, David Brown

David C. Brown

No abstract provided.

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Investigations Of Tandem Gma Welding Using A Flexible Computer Controlled Power Source System, Ruham Reis, John Norrish, Dominic Cuiuri, Alexander Nicholson Dec 2015

Investigations Of Tandem Gma Welding Using A Flexible Computer Controlled Power Source System, Ruham Reis, John Norrish, Dominic Cuiuri, Alexander Nicholson

Dominic Cuiuri

No abstract provided.

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Influence Of Shielding Gas On Fume Formation Rate And Particle Size Distribution For Optimised Gmaw, Kristin Carpenter, Brian Monaghan, Alexander Nicholson, Dominic Cuiuri, John Norrish Dec 2015

Influence Of Shielding Gas On Fume Formation Rate And Particle Size Distribution For Optimised Gmaw, Kristin Carpenter, Brian Monaghan, Alexander Nicholson, Dominic Cuiuri, John Norrish

Dominic Cuiuri

The influence of shielding gas on fume formation rate (FFR) and particle size distribution has been investigated by using a technique developed for automatic control of the welding voltage in gas metal arc welding (GMAW). The results for automatic control are compared with the use of a fixed voltage. Significant reductions in FFR and a general decrease in average particle size were observed using the automatic control technique. This reduction in FFR was attributed to improved metal transfer stability, via a reduction in the occurrence of repelled globular transfer, by promoting the 'drop-spray' transfer condition, together with a reduction in …

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The Australian Long Term Power Quality Monitoring Project, Sean Elphick, Vic Gosbell, Robert Barr Dec 2015

The Australian Long Term Power Quality Monitoring Project, Sean Elphick, Vic Gosbell, Robert Barr

Robert Barr

The Australian long term power quality monitoring project now involves over 500 sites over 5 years and is one of the largest and longest running in the world. The project necessitated the development of a monitoring strategy, including choosing the number of sites, the type of disturbances to monitor and a means of collecting information from a variety of instruments. The presentation of such a large amount of data must consider a variety of needs from the wide view of the network manager to the needs of area managers for details on specific sites. A key feature of the survey …

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Muscle Synergies Improve Estimation Of Knee Contact Forces During Walking, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd Dec 2015

Muscle Synergies Improve Estimation Of Knee Contact Forces During Walking, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd

Allison Kinney

This study investigates whether use of subject-specific muscle synergies can improve optimization predictions of muscle excitation patterns and knee contact forces during walking. Muscle synergies describe how a small number of neural commands generated by the nervous system can be linearly combined to produce the broad range of muscle electromyographic (EMG) signals measured experimentally. By quantifying the interdependence of individual EMG signals, muscle synergies provide dimensionality reduction for the neural control redundancy problem. Our hypothesis was that use of subjectspecific muscle synergies to limit muscle excitation patterns would improve prediction of muscle EMG patterns at the hip, knee, and ankle …

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Muscle Synergy Constraints Improve Prediction Of Knee Contact Force During Gait, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd Dec 2015

Muscle Synergy Constraints Improve Prediction Of Knee Contact Force During Gait, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd

Allison Kinney

Knowledge of patient-specific muscle and joint contact forces during activities of daily living could improve the treatment of movement-related disorders (e.g., osteoarthritis, stroke, cerebral palsy, Parkinson’s disease). Unfortunately, it is currently impossible to measure these quantities directly under common clinical conditions, and calculation of these quantities using computer models is limited by the redundant nature of human neural control (i.e., more muscles than theoretically necessary to actuate the available degrees of freedom in the skeleton). Walking is a particularly important task to understand, since loss of mobility is associated with increased morbidity and decreased quality of life. Though numerous musculoskeletal …

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Evaluation Of Different Optimal Control Problem Formulations For Solving The Muscle Redundancy Problem, Friedl De Groote, Allison Kinney, Anil Rao, Benjamin Fregly Dec 2015

Evaluation Of Different Optimal Control Problem Formulations For Solving The Muscle Redundancy Problem, Friedl De Groote, Allison Kinney, Anil Rao, Benjamin Fregly

Allison Kinney

This study evaluates several possible optimal control problem formulations for solving the muscle redundancy problem with the goal of identifying the most efficient and robust formulation. One novel formulation involves the introduction of additional controls that equal the time derivative of the states, resulting in very simple dynamic equations. The nonlinear equations describing muscle dynamics are then imposed as algebraic constraints in their implicit form, simplifying their evaluation. By comparing different problem formulations for computing muscle controls that can reproduce inverse dynamic joint torques during gait, we demonstrate the efficiency and robustness of the proposed novel formulation.

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Material Properties And Microstructural Characterization Of Specimens, T.J. Silverman, Allison Kinney, B. South, W. Yong, J.H. Koo Dec 2015

Material Properties And Microstructural Characterization Of Specimens, T.J. Silverman, Allison Kinney, B. South, W. Yong, J.H. Koo

Allison Kinney

The HiQ upgrade to the 3D Systems Vanguard selective laser sintering (SLS) machine incorporates a revised thermal calibration system and new software. This paper quantifies differences in mechanical and morphological properties of specimens built first using a Vanguard HS (high-speed) system and again using the same system with the HiQ upgrade applied. Standard specimens are built from DuraForm PA material and tested for tensile modulus, tensile strength, elongation at break, flexural modulus and Izod impact strength. The design of the specimen battery, the conduction of the tests and the significance of the results are discussed. The upgrade is found to …

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Synergies Controls Improve Prediction Of Knee Contact Forces And Muscle Excitations During Gait, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd Dec 2015

Synergies Controls Improve Prediction Of Knee Contact Forces And Muscle Excitations During Gait, Benjamin Fregly, Jonathan Walter, Allison Kinney, Scott Banks, Darryl D'Lima, Thor Besier, David Lloyd

Allison Kinney

This study investigates whether use of muscle excitation controls constructed from subjectspecific muscle synergy information can improve optimization prediction of knee contact forces and muscle excitations during walking. Muscle synergies quantify how a large number of experimental muscle electromyographic (EMG) signals can be reconstructed by linearly mixing a much smaller number of neural commands generated by the nervous system. Our hypothesis was that controlling all muscle excitations with a small set of experimentally calculated neural commands would improve prediction of knee contact forces and leg muscle excitations compared to using independently controlled muscle excitations.

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Comparison Of Material Properties And Microstructure Of Specimens Built Using The 3d Systems Vanguard Hs And Vanguard Hiq+Hs Sls Systems, T.J. Silverman, Allison Kinney, W. Yong, J.H. Koo Dec 2015

Comparison Of Material Properties And Microstructure Of Specimens Built Using The 3d Systems Vanguard Hs And Vanguard Hiq+Hs Sls Systems, T.J. Silverman, Allison Kinney, W. Yong, J.H. Koo

Allison Kinney

The HiQ upgrade to the 3D Systems Vanguard selective laser sintering (SLS) machine incorporates a revised thermal calibration system and new control software. The paper compares the tensile modulus, tensile strength, elongation at break, flexural modulus, Izod impact resistance and microstructure of two batteries of standard specimens built from recycled Duraform PA (Nylon 12). The first set is built on a Vanguard HS system and the second on the same system with the HiQ upgrade installed. The upgrade reduces user intervention, decreases total build time and improves surface finish. However, using the default processing parameters, tensile, flexure and impact properties …

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A Versatile Experimental Test Rig For Gma Welding Research, Gary Dean, Dominic Cuiuri, John Norrish, Christopher Cook Dec 2015

A Versatile Experimental Test Rig For Gma Welding Research, Gary Dean, Dominic Cuiuri, John Norrish, Christopher Cook

Dominic Cuiuri

Welding process research is severely hampered when adequate experimental equipment is not available. With the development of numerous welding processes and the control techniques associated with them, the need now exists for experimental equipment that offers the flexibility to control these processes and to set up parameters associated with the research. At the University of Wollongong an experimental research rig has been developed based on a digital signal processor control system that offers the researcher the facilities to study the various processes associated with GMA welding.

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A Flexible Control Program For Research And Development In Tandem Gma Welding, Ruham Reis, John Norrish, Dominic Cuiuri, Alexander Nicholson Dec 2015

A Flexible Control Program For Research And Development In Tandem Gma Welding, Ruham Reis, John Norrish, Dominic Cuiuri, Alexander Nicholson

Dominic Cuiuri

No abstract provided.

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Design And Construction Process Management, David Brown Dec 2015

Design And Construction Process Management, David Brown

David C. Brown

New approaches for improving design and construction processes have been used recently. Innovative methods for managing the requirements and quality of these processes will be discussed. A systematic data centric approach will be discussed as well as the processes of separating progress from performance. It discusses the integration of these processes in the planning, risk analysis, design, submission, construction, inspection, quality control and documentation phases.

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Science Panel Discussion Presentation: "Data Management In Biomedical Engineering: Needs And Implementation", Glenn Gaudette Dec 2015

Science Panel Discussion Presentation: "Data Management In Biomedical Engineering: Needs And Implementation", Glenn Gaudette

Glenn R. Gaudette

Glenn Gaudette, PhD, is an Associate Professor, Department of Biomedical Engineering, Worcester Polytechnic Institute. He discussed data management in his research laboratory, which is focused on regenerating mechanical and electrophysiological function in hearts with cardiovascular disease.

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Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel Simon, William Smith, Sergey Samorezov Dec 2015

Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel Simon, William Smith, Sergey Samorezov

Hanz Richter

Robotic testing can facilitate the development of new concepts, designs and control systems for prosthetic limbs. Human subject test clearances, safety and the lack of repeatability associated with human trials can be reduced or eliminated with automated testing, and test modalities are possible which are dangerous or inconvenient to attempt with patients. This paper describes the development, modeling, parameter estimation and control of a robot capable of reproducing two degree-of-freedom hip motion in the sagittal plane. Hip vertical displacement and thigh angle motion profiles are applied to a transfemoral prosthesis attached to the robot. A treadmill is used as walking …

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Comparing Mathematical And Heuristic Approaches For Scientific Data Analysis, Aparna Varde, Shuhui Ma, Mohammed Maniruzzaman, David Brown, Elke Rundensteiner, Richard Sisson Dec 2015

Comparing Mathematical And Heuristic Approaches For Scientific Data Analysis, Aparna Varde, Shuhui Ma, Mohammed Maniruzzaman, David Brown, Elke Rundensteiner, Richard Sisson

David C. Brown

Scientific data is often analyzed in the context of domain-specific problems, for example, failure diagnostics, predictive analysis, and computational estimation. These problems can be solved using approaches such as mathematical models or heuristic methods. In this paper we compare a heuristic approach based on mining stored data with a mathematical approach based on applying state-of-the-art formulae to solve an estimation problem. The goal is to estimate results of scientific experiments given their input conditions. We present a comparative study based on sample space, time complexity, and data storage with respect to a real application in materials science. Performance evaluation with …

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Engineering, Nutrient Removal, And Feedstock Conversion Evaluations Of Four Corn Stover Harvest Scenarios, Reed L. Hoskinson, Douglas L. Karlen, Stuart J. Birrell, Corey W. Radtke, W. W. Wilhelm Dec 2015

Engineering, Nutrient Removal, And Feedstock Conversion Evaluations Of Four Corn Stover Harvest Scenarios, Reed L. Hoskinson, Douglas L. Karlen, Stuart J. Birrell, Corey W. Radtke, W. W. Wilhelm

Douglas L Karlen

Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. A prototype one-pass harvest system was used to collect residue samples from a corn (Zea mays L.) field near Ames, IA. Four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut) were evaluated and are expressed as collected stover harvest indices (CSHI). High-cut top and high-cut bottom samples were obtained from the same plot in separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion yield and efficiency, and thermochemical conversion for each scenario were determined. Mean grain …

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Challenges Of Managing Liquid Swine Manure, Douglas Karlen, Cynthia A. Cambardella, Rameshwar S. Kanwar Dec 2015

Challenges Of Managing Liquid Swine Manure, Douglas Karlen, Cynthia A. Cambardella, Rameshwar S. Kanwar

Douglas L Karlen

Liquid swine manure can be a resource for providing essential plant nutrients and building soil resources, but its management for maximum productivity with minimum environmental impact is often very difficult. Failure to understand the challenges may result in expectations or even regulations that are impossible to achieve. Our objective is to provide producers and policy makers with information regarding agronomic and environmental challenges of liquid swine manure management based on results from a 6-year study with continuous corn (Zea mays L.) and a corn-soybean [Glycine max (L.) Merr.] rotation in Iowa. Challenges that we encountered are openly discussed to increase …

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Influence Of Corn Stover Harvest On Soil Quality Assessments At Multiple Locations Across The U.S., Diane E. Stott, Virginia L. Jin, Thomas F. Ducey, Douglas L. Karlen, Gary E. Varvel, Jane M. F. Johnson, John M. Baker, Shannon L. Osborne, Jeff M. Novak, Paul R. Adler, Greg W. Roth, Stuart J. Birrell Dec 2015

Influence Of Corn Stover Harvest On Soil Quality Assessments At Multiple Locations Across The U.S., Diane E. Stott, Virginia L. Jin, Thomas F. Ducey, Douglas L. Karlen, Gary E. Varvel, Jane M. F. Johnson, John M. Baker, Shannon L. Osborne, Jeff M. Novak, Paul R. Adler, Greg W. Roth, Stuart J. Birrell

Douglas L Karlen

Corn (Zea mays L.) stover has been identified as a biofuel feedstock due to its abundance and a perception that the residues are unused trash material. However, corn stover and other plant residues play a role in maintaining soil quality (health) and enhancing productivity, thus use of this abundant material as feedstock must be balanced with the need to protect the vital soil resource. Plant residues provide physical protection against erosion by wind and water, contribute to soil structure, nutrient cycling, and help sustain the soil microbiota. Replicated plots were established on productive soils at several locations (IA, IN, MN, …

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Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt Dec 2015

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Douglas L Karlen

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus ×giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced …

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Multilocation Corn Stover Harvest Effects On Crop Yields And Nutrient Removal, Douglas L. Karlen, Stuart J. Birrell, Jane M. F. Johnson, Shannon L. Osborne, Thomas E. Schumacher, Gary E. Varvel, Richard B. Ferguson, Jeff M. Novak, James R. Fredrick, John M. Baker, John A. Lamb, Paul R. Adler, Greg W. Roth, Emerson D. Nafziger Dec 2015

Multilocation Corn Stover Harvest Effects On Crop Yields And Nutrient Removal, Douglas L. Karlen, Stuart J. Birrell, Jane M. F. Johnson, Shannon L. Osborne, Thomas E. Schumacher, Gary E. Varvel, Richard B. Ferguson, Jeff M. Novak, James R. Fredrick, John M. Baker, John A. Lamb, Paul R. Adler, Greg W. Roth, Emerson D. Nafziger

Douglas L Karlen

Corn (Zea mays L.) stover was identified as an important feedstock for cellulosic bioenergy production because of the extensive area upon which the crop is already grown. This report summarizes 239 site-years of field research examining effects of zero, moderate, and high stover removal rates at 36 sites in seven different states. Grain and stover yields from all sites as well as N, P, and K removal from 28 sites are summarized for nine longitude and six latitude bands, two tillage practices (conventional vs no tillage), two stover-harvest methods (machine vs calculated), and two crop rotations {continuous corn (maize) …

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U.S. Billion-Ton Update: Biomass Supply For A Bioenergy And Bioproducts Industry, Robert D. Perlack, Laurence M. Eaton, Anthony F. Turhollow Jr., Matt H. Langholtz, Craig C. Brandt, Mark E. Downing, Robin L. Graham, Lynn L. Wright, Jacob M. Kavkewitz, Anna M. Shamey, Richard G. Nelson, Bryce J. Stokes, William L. Rooney, David J. Muth Jr., J. Richard Hess, Jared M. Abodeely, Chad Hellwinckel, Danial De La Torre Ugarte, Daniel C. Yoder, James P. Lyon, Timothy G. Rials, Timothy A. Volk, Thomas S. Buchholz, Lawrence P. Abrahamson, Robert P. Anex, Thomas B. Voigt, William Berguson, Don E. Riemenschneider, Douglas Karlen, Jane M. F. Johnson, Robert B. Mitchell, Kenneth P. Vogel, Edward P. Richard Jr., John Tatarko, Larry E. Wagner, Kenneth E. Skog, Patricia K. Lebow, Dennis P. Dykstra, Marilyn A. Buford, Patrick D. Miles, D. Andrew Scott, James H. Perdue, Robert B. Rummer, Jamie Barbour, John A. Stanturf, David B. Mckeever, Ronald S. Zalesny Jr., Edmund A. Gee, P. Daniel Cassidy, David Lightle Dec 2015

U.S. Billion-Ton Update: Biomass Supply For A Bioenergy And Bioproducts Industry, Robert D. Perlack, Laurence M. Eaton, Anthony F. Turhollow Jr., Matt H. Langholtz, Craig C. Brandt, Mark E. Downing, Robin L. Graham, Lynn L. Wright, Jacob M. Kavkewitz, Anna M. Shamey, Richard G. Nelson, Bryce J. Stokes, William L. Rooney, David J. Muth Jr., J. Richard Hess, Jared M. Abodeely, Chad Hellwinckel, Danial De La Torre Ugarte, Daniel C. Yoder, James P. Lyon, Timothy G. Rials, Timothy A. Volk, Thomas S. Buchholz, Lawrence P. Abrahamson, Robert P. Anex, Thomas B. Voigt, William Berguson, Don E. Riemenschneider, Douglas Karlen, Jane M. F. Johnson, Robert B. Mitchell, Kenneth P. Vogel, Edward P. Richard Jr., John Tatarko, Larry E. Wagner, Kenneth E. Skog, Patricia K. Lebow, Dennis P. Dykstra, Marilyn A. Buford, Patrick D. Miles, D. Andrew Scott, James H. Perdue, Robert B. Rummer, Jamie Barbour, John A. Stanturf, David B. Mckeever, Ronald S. Zalesny Jr., Edmund A. Gee, P. Daniel Cassidy, David Lightle

Douglas L Karlen

The Report, Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply (generally referred to as the Billion-Ton Study or 2005 BTS), was an estimate of “potential” biomass within the contiguous United States based on numerous assumptions about current and future inventory and production capacity, availability, and technology. In the 2005 BTS, a strategic analysis was undertaken to determine if U.S. agriculture and forest resources have the capability to potentially produce at least one billion dry tons of biomass annually, in a sustainable manner—enough to displace approximately 30% of the country’s present petroleum …

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Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom Dec 2015

Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom

Douglas L Karlen

The objective of this study was to explore if more crop-specific plant growth modules can improve simulations of crop yields, and N in tile flow under different management practices compared with a generic plant growth module. We calibrated and evaluated the Root Zone Water Quality Model (RZWQM) with the Decision Support for Agrotechnology Transfer (DSSAT v3.5) plant growth modules (RZWQM–DSSAT) for simulating tillage (NT — no till, RT — ridge till, CP — chisel plow, and MP — moldboard plow), crop rotation {CC — continuous corn, and CS — corn (Zea mays L.)–soybean [Glycine max (L.) Merr.]}, and nitrogen (N) …

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Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer Dec 2015

Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer

Douglas L Karlen

Quantifying energy issues associated with agricultural systems, even for a two-crop corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) rotation, is not a simple task. It becomes even more complicated if the goal is to include all aspects of sustainability (i.e., economic, environmental, and social). This Issue Paper examines energy issues associated with and affecting corn/soybean rotations by first defining the size of the system from both a U.S. and global perspective and then establishing boundaries based on the Farm Bill definition of sustainability. This structured approach is essential to help quantify energy issues within corn/soybean systems that …

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Impacts Of Swine Manure Application And Alternative N-Management Practices On Productivity, Sustainability And Water Quality, Rameshwar S. Kanwar, Douglas Karlen, Cynthia A. Cambardella, Thomas Moorman, Thomas R. Steinheimer, Thomas S. Colvin Dec 2015

Impacts Of Swine Manure Application And Alternative N-Management Practices On Productivity, Sustainability And Water Quality, Rameshwar S. Kanwar, Douglas Karlen, Cynthia A. Cambardella, Thomas Moorman, Thomas R. Steinheimer, Thomas S. Colvin

Douglas L Karlen

In the fourth year of this ongoing project, the effects of nine N-management practices under different tillage and cropping systems were evaluated. Forty experimental plots equipped with individual sumps and subsurface drainage metering and monitoring devices were used for the study. Overall results indicate that manure application rates and methods can be successfully managed for corn-soybean systems without damaging the water quality if the appropriate amount of N from swine manure can be applied.

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