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Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers 2016 Iowa State University

Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers

John E. Sawyer

Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.


A System Dynamics Model Of The Pacific Coast Rockfish Fishery, Wayne Wakeland, Olgay Cangur, Guillermo Rueda, Astrid Scholz 2016 Portland State University

A System Dynamics Model Of The Pacific Coast Rockfish Fishery, Wayne Wakeland, Olgay Cangur, Guillermo Rueda, Astrid Scholz

Wayne W. Wakeland

This paper presents a model of the dynamic behavior of the yellowtail rockfish of the Pacific Coast of the United States. The purpose of the model is to generate endogenously the historical data for fish population, fishing vessels, regulatory parameters, and fish harvest. The model was subjected to a variety of tests to determine its sensitivity to changes in key parameters and initial values, including extreme conditions. Model results indicate that acceptable biological catch and fleet capacity must be adjusted quickly in response to changing conditions, in order to improve fishery sustainability. Additional analysis reinforces the policy of setting the ...


System Dynamics Implementation Of A Model Of Population And Resource Dynamics With Adaptation, Takuro Uehara, Yoko Nagase, Wayne Wakeland 2016 Portland State University

System Dynamics Implementation Of A Model Of Population And Resource Dynamics With Adaptation, Takuro Uehara, Yoko Nagase, Wayne Wakeland

Wayne W. Wakeland

We build and analyze a dynamic ecological economic model that incorporates endogenous innovation on input substitutability. The use of the system dynamics method allows us to depart from conventional equilibrium thinking and conduct an out-of-equilibrium (adaptation) analysis. Simulation results show that while improvement in input substitutability will expand an economy, this change alone may not improve sustainability measured by indicators such as utility-per-capita and natural resource stock. It could, however, be possible that in combination with other technological progress, improvement in input substitutability will contribute to sustainable development. Sensitivity analysis also indicates a possible complication with the use of exogenous ...


Pattern Does Not Equal Process: Exactly When Is Sex Environmentally Determined?, M. Nicole Valenzuela, Dean C. Adams, Fredric J. Janzen 2016 Iowa State University

Pattern Does Not Equal Process: Exactly When Is Sex Environmentally Determined?, M. Nicole Valenzuela, Dean C. Adams, Fredric J. Janzen

Fredric Janzen

Of prime importance in evolutionary biology are the description of pattern and explanations of process. Frequently, however, multiple processes can explain a given pattern. Such cases require experimental protocols or research criteria to distinguish among alternatives so pattern can be critically assigned to process. Noteworthy examples of this approach include evaluating adaptations and identifying character displacement (Gould and Lewontin 1979; Schluter and McPhail 1992). The field of vertebrate sex determination similarly requires such criteria.


Implications Of Changes (Structural And Market) On Farm Management And Marketing Research, George R. Allen, Lester S. Kellogg, G. Edward Schuh, Vernon W. Pherson, Reynold P. Dahl, Rex F. Daly, Dale E. Hathaway, Neil E. Harl, Earl O. Heady, A. Gordon Ball, Glenn L. Johnson, Dale O. Anderson, Lowell D. Hill, John C. Redman, Robert W. Rudd, B. F. Jones, A. Allen Schmid, Karl A. Fox, George D. Irwin, R. L. Kohls, John E. Lee Jr., Thomas T. Stout 2016 W.R. Grace

Implications Of Changes (Structural And Market) On Farm Management And Marketing Research, George R. Allen, Lester S. Kellogg, G. Edward Schuh, Vernon W. Pherson, Reynold P. Dahl, Rex F. Daly, Dale E. Hathaway, Neil E. Harl, Earl O. Heady, A. Gordon Ball, Glenn L. Johnson, Dale O. Anderson, Lowell D. Hill, John C. Redman, Robert W. Rudd, B. F. Jones, A. Allen Schmid, Karl A. Fox, George D. Irwin, R. L. Kohls, John E. Lee Jr., Thomas T. Stout

Neil Harl

This conference was really an outgrowth of an earlier conference on Structural Changes in Commercial Agriculture (CAED Report 24) held in Chicago, April 12-14, 1965. While the earlier conference emphasized structural changes in the agricultural industry and their implications for education and extension, the 1967 conference focused on research.


Seeding Method Influences Warm-Season Grass Abundance And Distribution But Not Local Diversity In Grassland Restoration, Kathryn Anne Yurkonis, Brian J. Wilsey, Kirk A. Moloney, Pauline Drobney, Diane L. Larson 2016 Iowa State University

Seeding Method Influences Warm-Season Grass Abundance And Distribution But Not Local Diversity In Grassland Restoration, Kathryn Anne Yurkonis, Brian J. Wilsey, Kirk A. Moloney, Pauline Drobney, Diane L. Larson

Kirk Moloney

Ecological theory predicts that the arrangement of seedlings in newly restored communities may influence future species diversity and composition. We test the prediction that smaller distances between neighboring seeds in drill seeded grassland plantings would result in lower species diversity, greater weed abundance, and larger conspecific patch sizes than otherwise similar broadcast seeded plantings. A diverse grassland seed mix was either drill seeded, which places seeds in equally spaced rows, or broadcast seeded, which spreads seeds across the ground surface, into 24 plots in each of three sites in 2005. In summer 2007, we measured species abundance in a 1 ...


Thiophene Based Molecular Sensors Towards Mercury Detection, Austin K. Shigemoto, Carolyn N. Virca, Sam Underwood, Lauren Shetterly, Theresa M. McCormick 2016 Portland State University

Thiophene Based Molecular Sensors Towards Mercury Detection, Austin K. Shigemoto, Carolyn N. Virca, Sam Underwood, Lauren Shetterly, Theresa M. Mccormick

Theresa M. McCormick

Toxic heavy metals such as mercury have increased in concentration in the environment due to pollution. Inorganic mercury in the environment can be later converted to a more toxic form: methylmercury. Regular consumption of fish containing methylmercury can lead to several cognitive and motor disorders as well as Minamata disease. The current methods used to detect both methylmercury and inorganic mercury in sea life and drinking water involve long sample preparation and cost. In order to more efficiently track this toxic metal in the environment and identify contaminated food and water sources, a cheaper and faster method of detection is ...


Ga Based Optimal Control For Maximizing Pv Penetration At Transmission, Chittesh Veni Chandran 2016 Dublin Institute of Technology

Ga Based Optimal Control For Maximizing Pv Penetration At Transmission, Chittesh Veni Chandran

Student Journal of Energy Research

Utilization of distributed energy resources (DER’s) like photo-voltaic generators, is one of the possible solution for present scenario of energy crisis. Most of the study suggest the implementation of PV power stations at distribution level. In this paper detailed theoretical analyses of the impact of large scale PV on transmission level is analysed. The preliminary section of this paper provides literature review with specifications of IEEE-14 bus network. Two methodology ie, constant load method and maximum loading method is implemented here. A test study is done in IEEE 14 bus to find out the optimal location of solar photo-voltaic ...


Risk Assessment For Two Multi Terminal Vsc-Hvdc Control Schemes, Roberto Sandano 2016 Dublin Institute of Technology

Risk Assessment For Two Multi Terminal Vsc-Hvdc Control Schemes, Roberto Sandano

Student Journal of Energy Research

High Voltage Direct Current (HVDC) connections have been in operation since the 1950s. The vast majority of which are point to point connections and use Line Commutated Converter (LCC) technology. Since the late nineties Voltage Source Converter (VSC) technology has become a feasible choice on HVDC transmission systems [1]. Research is now focused in the development of Multi-terminal (MT)-HVDC system which will facilitate the collection of energy from distant dispersed renewable energy resources and transport this energy to load centres.


Power Quality Improvement In Fuel Cell Based Hybrid Power System Using Statcom, Sandipan Patra 2016 Dublin Institute of Technology

Power Quality Improvement In Fuel Cell Based Hybrid Power System Using Statcom, Sandipan Patra

Student Journal of Energy Research

This paper presents the power quality improvement in a microgrid, supplying a nonlinear and unbalanced load using fuzzy logic controller based static synchronous compensator (STATCOM). The microgrid contains a hybrid combination photovoltaic (PV), fuel cell (FC) along with the battery energy storage system (BESS) where a decentralized power sharing algorithm is used to control its power management. Here, STATCOM is used as a compensator for the hybrid system to reduce the harmonics in the voltage and current profile at the point of common coupling (PCC). The current reference is generated taking into account, the active and reactive power to be ...


Reducing Pollen Dispersal Using Forest Windbreaks, Carol Auer, Thomas Meyer, Vernie Sagun 2016 University of Connecticut - Storrs

Reducing Pollen Dispersal Using Forest Windbreaks, Carol Auer, Thomas Meyer, Vernie Sagun

Plant Science Articles

The adoption of genetically engineered (GE) crops has created a demand for practical methods to mitigate pollen dispersal and gene flow. The goal of this project was to measure the ability of a narrow forest windbreak to reduce downwind pollen fluxes from switchgrass (Panicum virgatum L.), a North American grass and model biofuels feedstock. Switchgrass fields were established in two identical plots where one had a forest windbreak and the other was in an open (control) site. Switchgrass reproduction, pollen dispersal, wind speed, and wind direction were measured over two years. Daily release of switchgrass pollen peaked at 11:00-13 ...


Using A High-Altitude Balloon Platform To Observe And Measure Ozone Uptake Over Agricultural Landscapes In Central Illinois, Cody Sabo 2016 DePaul University

Using A High-Altitude Balloon Platform To Observe And Measure Ozone Uptake Over Agricultural Landscapes In Central Illinois, Cody Sabo

DePaul Discoveries

An increase in the amount of factories and machines that emit greenhouse gases (GHGs) has caused the concentration of GHGs to rise steeply since the industrial era. These emissions create compounds that react with sunlight to form ozone, a GHG. Ozone not only traps heat in the atmosphere causing long-term global issues, but it also causes direct harm to both plants and animals. The damage that ozone causes to plants is due to plants taking the gas up through their stomata. Measuring ozone uptake has traditionally been a difficult and expensive process. This study proposes a novel approach towards measuring ...


Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole 2016 DePaul University

Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole

DePaul Discoveries

Isoprene, the most abundant hydrocarbon in the atmosphere, plays a significant role in atmospheric chemistry. Its reactions with NOx lead to the formation of ozone in the lower troposphere, which is harmful to plants and detrimental to human health. As air temperatures and CO2 concentrations increase with climate change, it is uncertain how isoprene emissions from plants will respond. We hypothesized that isoprene emissions will increase with the combination of increasing temperature and CO­2 concentrations. We predict that oaks grown at a higher temperature will exhibit an increase in isoprene emissions with combined short-term increases in temperature ...


Implications Of Manipulations Of Soil Quality On The Growth Of European Buckthorn (Rhamnus Cathartica) In A Greenhouse, Sam L. Pepper, Liam Heneghan 2016 DePaul University

Implications Of Manipulations Of Soil Quality On The Growth Of European Buckthorn (Rhamnus Cathartica) In A Greenhouse, Sam L. Pepper, Liam Heneghan

DePaul Discoveries

European buckthorn (Rhamnus cathartica L.) is an invasive shrub that is capable of changing the nitrogen content of a soil through the deposition of its nitrogen rich leaf litter. This change creates conditions that may favor recolonizing by buckthorn and negatively affect the growth of native plants. In this greenhouse experiment, we examined the effect of altering soil quality by adding mulch comprised of buckthorn wood on above and belowground biomass, stem length and leaf production of buckthorn saplings. We found that buckthorn saplings planted in buckthorn mulch had reduced stem length and leaf production compared to growth in control ...


Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David L. Kulhavy, Daniel R. Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung 2016 Stephen F Austin State University

Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David L. Kulhavy, Daniel R. Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung

International Journal of Geospatial and Environmental Research

Slope distance was measured between the top of 30 light poles and their respective ground level coordinate identified within a central parking lot on the campus of Stephen F. Austin State University, Nacogdoches, Texas. Slope distance measured using Pictometry® hyperspatial 4-inch (10.2 centimeters) multispectral imagery within a web based interface was compared to in situ total station and tape measured slope distance. The range for mean slope distance for Pictometry®, total station, and tape measured slope distance was 0.05 meters. Mean slope distance was 15.36 meters, 15.37 meters, and 15.41 meters for Pictometry®, total station ...


Carbon Sequestration In Managed Temperate Coniferous Forests Under Climate Change, Caren C. Dymond, Sarah Beukema, Craig R. Nitschke, K. David Coates, Robert M. Scheller 2016 B.C. Ministry of Forests, Lands, and Natural Resource Operations

Carbon Sequestration In Managed Temperate Coniferous Forests Under Climate Change, Caren C. Dymond, Sarah Beukema, Craig R. Nitschke, K. David Coates, Robert M. Scheller

Robert M. Scheller

Management of temperate forests has the potential to increase carbon sinks and mitigate climate change. However, those opportunities may be confounded by negative climate change impacts. We therefore need a better understanding of climate change alterations to temperate forest carbon dynamics before developing mitigation strategies. The purpose of this project was to investigate the interactions of species composition, fire, management, and climate change in the Copper–Pine Creek valley, a temperate coniferous forest with a wide range of growing conditions. To do so, we used the LANDIS-II modelling framework including the new Forest Carbon Succession extension to simulate forest ecosystems ...


Low-Cost Hab Platform To Measure Particulate Matter In The Troposphere, Mark J. Potosnak, Bernhard Beck-Winchatz, Paul Ritter 2016 DePaul University

Low-Cost Hab Platform To Measure Particulate Matter In The Troposphere, Mark J. Potosnak, Bernhard Beck-Winchatz, Paul Ritter

2016 Academic High Altitude Conference

High-altitude balloons (HABs) are an engaging platform for formal and informal STEM education. However, the logistics of launching, chasing and recovering a payload on a 1200 g or 1500 g balloon can be daunting for many novice school groups and citizen scientists, and the cost can be prohibitive. In addition, there are many interesting scientific applications that do not require reaching the stratosphere. In this poster presentation we discuss a novel approach based on small (30 g) balloons that are cheap and easy to handle, and low-cost tracking devices (SPOT and 900 MHz spread spectrum) that do not require a ...


Global Land Surface Emissivity Estimation From Amsr2 Observations, Satya Prakash, Hamid Norouzi, Marzieh Azarderakhsh, Reginald Blake, Kibrewossen Tesfagiorgis 2016 CUNY New York City College of Technology

Global Land Surface Emissivity Estimation From Amsr2 Observations, Satya Prakash, Hamid Norouzi, Marzieh Azarderakhsh, Reginald Blake, Kibrewossen Tesfagiorgis

Publications and Research

A reliable estimate of emissivity is critical for a wide range of applications for the atmosphere, the biosphere, the lithosphere, the cryosphere, and the hydrosphere. This study uses three years (August 2012 – July 2015) of data from the Advanced Microwave Scanning Radiometer-2 (AMSR2) sensor that is onboard the Global Change Observation Mission 1st Water (GCOM-W1) satellite to explore estimates of instantaneous global land emissivity. A method is adopted to remove the known inconsistency in penetration depths between microwave brightness temperatures and infrared-based ancillary data that could cause differences between day and night emissivity estimates. After removing the diurnal atmospheric effects ...


Against Rhythm: How Postmodern Humans Can Wake Up And Find Their Groove: Paul Morgan At Tedxwestchester, Paul A. Morgan 2016 West Chester University of Pennsylvania

Against Rhythm: How Postmodern Humans Can Wake Up And Find Their Groove: Paul Morgan At Tedxwestchester, Paul A. Morgan

Paul Morgan

No abstract provided.


Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell 2016 University of Dayton

Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell

Kevin Hallinan

Energy use data for the eight-year period 2003–2010 was analyzed for over 1200 single family residences in Village of Yellow Springs, Ohio. Electricity, natural gas, residential building, and weather databases are merged to permit determination of the energy intensity of each home in the village. The energy use intensity for each home is disaggregated into weather independent and weather dependent electric and natural gas use. This use is compared to typical baseline, cooling, and heating energy use for the region. From this comparison, priority homes are identified for energy reduction investment. Collective potential low cost energy reduction is estimated ...


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