25 research outputs found
Results from 2012 Vegetation Monitoring in Prairie and Old Field Habitats Following Shrub Removal at the North Chicago Wetland Mitigation Site, Lake County, Illinois
This report focuses on results from vegetation monitoring in terrestrial plant communities during 2012 and compares trends among reference prairie, transect prairie, and old field habitats. There are four main questions: 1. What are the site trends in species composition, total richness, and floristic quality and, for old field and prairie habitats (combining reference prairie and transect prairie habitats), what are the changes in species composition and abundance? 2. Based on 2012 sample data, are there significant between-subjects differences (vegetation types) with regard to ground layer and shrub/sapling parameters (e.g., composition, species richness, diversity, and cover - see Methods for full list and parameter definitions)? 3. Are there significant within-subject differences (year) in these parameters since the 2009 baseline data for each vegetation type and when (what year) do the difference occur? 4. What are the between-subjects and within-subjects interactions (i.e., vegetation type x sample year) for selected vegetation parameters since 2009?Illinois Tollway Authorityunpublishednot peer reviewe
A low-power, jamming, magnetorheological valve using electropermanent magnets suitable for distributed control in soft robots
Abstract
Magnetorheological (MR) valves are an attractive way to make reliable valves with no moving parts. MR fluid valves operate by powering an electromagnet positioned near a constriction through which MR fluid is flowing. However, these valves are high-power devices, consuming on the order of watts of power while closed, and the electromagnets and flow paths are relatively bulky. Due to their power draw and size, they are unsuitable for many miniaturized and portable applications which would otherwise benefit from a solid state valve. In this paper, we introduce a low power, jamming MR valve that makes use of an electropermanent magnet, which can provide either a strong magnetic field or no field, with no continuous power draw and no moving parts. The resulting valve has overall dimensions of 4× 4×6mm, a mass of 0.476g, material costs of $7.32 per valve USD at quantity 100, holds over 415 kPa of pressure, and leaks only 0.02g of fluid over a 24h period when held at 105 kPa. These valves are well suited for use in soft robots, e.g. robots composed of stretchable elastomers and may allow for increased degrees of freedom in soft robotic designs. We discuss the design considerations for making MR valves, study the effect of different fluids and valve sizes, develop a numerical framework for simulation and further valve design, and demonstrate the use of a MR valve to control the actuation of a soft robotic appendage.</jats:p
Modeling National Embedded Phosphorus Flows of Corn Ethanol Distillers’ Grains to Elucidate Nutrient Reduction Opportunities
Freshwater quality and ecosystem impairment associated
with excess
phosphorus (P) loadings have led to federally mandated P reduction
for certain organic waste streams. Phosphorus reduction from livestock
and poultry feeds such as corn ethanol distillers’ grains (DGs)
presents a centralized strategy for reducing P loss from animal manurein
agriculturally intensive states, but little is known about the actual
distribution and geospatial P contributions of DGs as animal feed.
Here, a county-level flow network for corn ethanol DGs was simulated
in the United States to elucidate opportunities for P reduction and
the potential for nutrient trading between centralized sources. Overall,
the estimated P in DGs that was transferred to US animal feeding operations
was nearly twice that present in all human waste prior to treatment.
Simulation results suggest that Midwestern states account for an estimated
63% of domestic DG usage, with 72% utilized within the state of production.
County-level data were also used to highlight the potential of using
nutrient trading markets to incentivize P recovery from DGs at biorefineries
within an agriculturally intensive watershed region in Iowa. In summary,
corn ethanol biorefineries represent a key leverage point for sustainable
P management at the national and local scales
Modeling National Embedded Phosphorus Flows of Corn Ethanol Distillers’ Grains to Elucidate Nutrient Reduction Opportunities
Freshwater quality and ecosystem impairment associated
with excess
phosphorus (P) loadings have led to federally mandated P reduction
for certain organic waste streams. Phosphorus reduction from livestock
and poultry feeds such as corn ethanol distillers’ grains (DGs)
presents a centralized strategy for reducing P loss from animal manurein
agriculturally intensive states, but little is known about the actual
distribution and geospatial P contributions of DGs as animal feed.
Here, a county-level flow network for corn ethanol DGs was simulated
in the United States to elucidate opportunities for P reduction and
the potential for nutrient trading between centralized sources. Overall,
the estimated P in DGs that was transferred to US animal feeding operations
was nearly twice that present in all human waste prior to treatment.
Simulation results suggest that Midwestern states account for an estimated
63% of domestic DG usage, with 72% utilized within the state of production.
County-level data were also used to highlight the potential of using
nutrient trading markets to incentivize P recovery from DGs at biorefineries
within an agriculturally intensive watershed region in Iowa. In summary,
corn ethanol biorefineries represent a key leverage point for sustainable
P management at the national and local scales
Modeling National Embedded Phosphorus Flows of Corn Ethanol Distillers’ Grains to Elucidate Nutrient Reduction Opportunities
Freshwater quality and ecosystem impairment associated
with excess
phosphorus (P) loadings have led to federally mandated P reduction
for certain organic waste streams. Phosphorus reduction from livestock
and poultry feeds such as corn ethanol distillers’ grains (DGs)
presents a centralized strategy for reducing P loss from animal manurein
agriculturally intensive states, but little is known about the actual
distribution and geospatial P contributions of DGs as animal feed.
Here, a county-level flow network for corn ethanol DGs was simulated
in the United States to elucidate opportunities for P reduction and
the potential for nutrient trading between centralized sources. Overall,
the estimated P in DGs that was transferred to US animal feeding operations
was nearly twice that present in all human waste prior to treatment.
Simulation results suggest that Midwestern states account for an estimated
63% of domestic DG usage, with 72% utilized within the state of production.
County-level data were also used to highlight the potential of using
nutrient trading markets to incentivize P recovery from DGs at biorefineries
within an agriculturally intensive watershed region in Iowa. In summary,
corn ethanol biorefineries represent a key leverage point for sustainable
P management at the national and local scales
Modeling National Embedded Phosphorus Flows of Corn Ethanol Distillers’ Grains to Elucidate Nutrient Reduction Opportunities
Freshwater quality and ecosystem impairment associated
with excess
phosphorus (P) loadings have led to federally mandated P reduction
for certain organic waste streams. Phosphorus reduction from livestock
and poultry feeds such as corn ethanol distillers’ grains (DGs)
presents a centralized strategy for reducing P loss from animal manurein
agriculturally intensive states, but little is known about the actual
distribution and geospatial P contributions of DGs as animal feed.
Here, a county-level flow network for corn ethanol DGs was simulated
in the United States to elucidate opportunities for P reduction and
the potential for nutrient trading between centralized sources. Overall,
the estimated P in DGs that was transferred to US animal feeding operations
was nearly twice that present in all human waste prior to treatment.
Simulation results suggest that Midwestern states account for an estimated
63% of domestic DG usage, with 72% utilized within the state of production.
County-level data were also used to highlight the potential of using
nutrient trading markets to incentivize P recovery from DGs at biorefineries
within an agriculturally intensive watershed region in Iowa. In summary,
corn ethanol biorefineries represent a key leverage point for sustainable
P management at the national and local scales
Mapping the National Phosphorus Recovery Potential from Centralized Wastewater and Corn Ethanol Infrastructure
Anthropogenic
discharge of excess phosphorus (P) to water bodies
and increasingly stringent discharge limits have fostered interest
in quantifying opportunities for P recovery and reuse. To date, geospatial
estimates of P recovery potential in the United States (US) have used
human and livestock population data, which do not capture the engineering
constraints of P removal from centralized water resource recovery
facilities (WRRFs) and corn ethanol biorefineries where P is concentrated
in coproduct animal feeds. Here, renewable P (rP) estimates from plant-wide
process models were used to create a geospatial inventory of recovery
potential for centralized WRRFs and biorefineries, revealing that
individual corn ethanol biorefineries can generate on average 3 orders
of magnitude more rP than WRRFs per site, and all corn ethanol biorefineries
can generate nearly double the total rP of WRRFs across the US. The
Midwestern states that make up the Corn Belt have the largest potential
for P recovery and reuse from both corn biorefineries and WRRFs with
a high degree of co-location with agricultural P consumption, indicating
the untapped potential for a circular P economy in this globally significant
grain-producing region
Mapping the National Phosphorus Recovery Potential from Centralized Wastewater and Corn Ethanol Infrastructure
Anthropogenic
discharge of excess phosphorus (P) to water bodies
and increasingly stringent discharge limits have fostered interest
in quantifying opportunities for P recovery and reuse. To date, geospatial
estimates of P recovery potential in the United States (US) have used
human and livestock population data, which do not capture the engineering
constraints of P removal from centralized water resource recovery
facilities (WRRFs) and corn ethanol biorefineries where P is concentrated
in coproduct animal feeds. Here, renewable P (rP) estimates from plant-wide
process models were used to create a geospatial inventory of recovery
potential for centralized WRRFs and biorefineries, revealing that
individual corn ethanol biorefineries can generate on average 3 orders
of magnitude more rP than WRRFs per site, and all corn ethanol biorefineries
can generate nearly double the total rP of WRRFs across the US. The
Midwestern states that make up the Corn Belt have the largest potential
for P recovery and reuse from both corn biorefineries and WRRFs with
a high degree of co-location with agricultural P consumption, indicating
the untapped potential for a circular P economy in this globally significant
grain-producing region
