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Review Of Robotic Technology For Strawberry Production, S. G. Defterli, Yeyin Shi, Yunjun Xu 2015 University of Central Florida

Review Of Robotic Technology For Strawberry Production, S. G. Defterli, Yeyin Shi, Yunjun Xu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

With an increasing world population in need of food and a limited amount of land for cultivation, higher efficiency in agricultural production, especially fruits and vegetables, is increasingly required. The success of agricultural production in the marketplace depends on its quality and cost. The cost of labor for crop production, harvesting, and post-harvesting operations is a major portion of the overall production cost, especially for specialty crops such as strawberry. As a result, a multitude of automation technologies involving semi-autonomous and autonomous robots have been utilized, with an aim of minimizing labor costs and operation time to achieve a considerable …


Gc/Ms Analysis Of Some Extractives From Eichhornia Crassipes, Héctor A. Fileto-Pérez, O. Miriam Rutiaga-Quiñones, Mark D. Sytsma, Isabelle M. Lorne, Wentai Luo, James F. Pankow, José G. Rutiaga-Quiñones 2015 Instituto Tecnológico de Durango

Gc/Ms Analysis Of Some Extractives From Eichhornia Crassipes, Héctor A. Fileto-Pérez, O. Miriam Rutiaga-Quiñones, Mark D. Sytsma, Isabelle M. Lorne, Wentai Luo, James F. Pankow, José G. Rutiaga-Quiñones

Environmental Science and Management Faculty Publications and Presentations

Eichhornia crassipes (water hyacinth) is an invasive weed that causes serious issues for rivers, lakes, and other reservoirs around the world, although it can be an excellent source for bioactive compounds such as phytosterols and some steroids found in many plants. In this study, water hyacinth samples from both Durango and Distrito Federal in Mexico were collected. Ascendant extracts (cyclohexane, hexane, acetone, and methanol) from their leaves, stems, and roots were analyzed. Using boron trifluoride (similar to 10% [similar to 1.3 M] in 1-butanol), all extracts were derivatized. Twenty-four derivatized samples were analyzed using a gas chromatography-mass spectrometry (GC/MS) method. …


Towards Effective Design Treatment For Right Turns At Intersections With Bicycle Traffic, David Hurwitz, Mafruhatul Jannat, Jennifer Warner, Christopher M. Monsere, Ali Razmpa 2015 Oregon State University

Towards Effective Design Treatment For Right Turns At Intersections With Bicycle Traffic, David Hurwitz, Mafruhatul Jannat, Jennifer Warner, Christopher M. Monsere, Ali Razmpa

Civil and Environmental Engineering Faculty Publications and Presentations

The overall goal of this research was to quantify the safety performance of alternative traffic control strategies to mitigate right-turning vehicle-bicycle crashes at signalized intersections in Oregon. The ultimate aim was to provide useful design guidance to potentially mitigate these collision types at the critical intersection configurations. This report includes a comprehensive review of more than 150 scientific and technical articles that relate to bicycle-motor vehicle crashes. A total of 504 right-hook crashes were identified from vehicle path information in the Oregon crash data from 2007-2011, mapped and reviewed in detail to identify the frequency and severity of crashes by …


Ion Exchange-Precipitation For Nutrient Recovery From Dilute Wastewater, A. T. Williams, Daniel Zitomer, Brooke K. Mayer 2015 Marquette University

Ion Exchange-Precipitation For Nutrient Recovery From Dilute Wastewater, A. T. Williams, Daniel Zitomer, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Regulated phosphorus (P) and nitrogen (N) discharges and the cost of fertilizer provide economic drivers for nutrient removal and recovery from wastewater. This study used ion exchange (IX) in dilute (domestic) wastewater to concentrate nutrients with subsequent recovery by struvite precipitation. This is the first tertiary wastewater treatment study directly comparing P removal using a range of Fe, Cu, and Al-based media followed by clinoptilolite IX columns for N removal and precipitation using the combined regenerants. Phosphate removal prior to breakthrough was 0.5–2.0 g P Lmedia−1, providing effluent concentrations −1 PO4-P and −1 NH4 …


How To Estimate Pedestrian Demand, Kelly Clifton, Patrick Allen Singleton, Christopher D. Muhs, Robert J. Schneider 2015 Portland State University

How To Estimate Pedestrian Demand, Kelly Clifton, Patrick Allen Singleton, Christopher D. Muhs, Robert J. Schneider

TREC Project Briefs

There is growing support to improve the quality of the walking environment and make investments to promote pedestrian travel. Such efforts often require analytical non-motorized planning tools to estimate levels of pedestrian demand that are sensitive to environmental and demographic factors at an appropriate scale. Despite this interest and need, current forecasting tools, particularly regional travel demand models, often fall short.

To address this gap, Oregon Metro and NITC researcher Kelly Clifton worked together to develop a pedestrian demand estimation tool. For generations, planners have been using statistical models to forecast travel demand, but these models have traditionally been auto-centered. …


Weighting The Perceived Importance Of Minimising Economic, Social, And Environmental/Cultural Risks In Flood Risk Management, Zeinab Bedri, John O'Sullivan 2015 Technological University Dublin

Weighting The Perceived Importance Of Minimising Economic, Social, And Environmental/Cultural Risks In Flood Risk Management, Zeinab Bedri, John O'Sullivan

Reports

A new national flood policy adopted in Ireland in 2004 set out that a range of flood-related impacts should be taken into account in planning flood risk management strategies and projects, including impacts on people, properties, the environment and cultural heritage. This was reinforced by the 2007 EU 'Floods' Directive that is aimed at the reduction of adverse consequences of flooding for human health, the environment, cultural heritage and economic activity.

In 2006, the Office of Public Works (OPW) began the National Catchment-based Flood Risk Assessment and Management (CFRAM) Programme through a series of pilot studies. A Multi-Criteria Analysis (MCA) …


An Upscaled Approach For Transport In Media With Extended Tailing Due To Back-Diffusion Using Analytical And Numerical Solutions Of The Advection Dispersion Equation, Jack C. Parker, Ungtae Kim 2015 University of Tennessee, Knoxville

An Upscaled Approach For Transport In Media With Extended Tailing Due To Back-Diffusion Using Analytical And Numerical Solutions Of The Advection Dispersion Equation, Jack C. Parker, Ungtae Kim

Civil and Environmental Engineering Faculty Publications

The mono-continuum advection-dispersion equation (mADE) is commonly regarded as unsuitable for application to media that exhibit rapid breakthrough and extended tailing associated with diffusion between high and low permeability regions. This paper demonstrates that the mADE can be successfully used to model such conditions if certain issues are addressed. First, since hydrodynamic dispersion, unlike molecular diffusion, cannot occur upstream of the contaminant source, models must be formulated to prevent “back-dispersion.” Second, large variations in aquifer permeability will result in differences between volume-weighted average concentration (resident concentration) and flow-weighted average concentration (flux concentration). Water samples taken from wells may be regarded …


High-Solids Anaerobic Digestion Of The Organic Fraction Of Municipal Solid Waste State Of The Art, Outlook In Florida, And Enhancing Methane Yields From Lignocellulosic Wastes, Gregory Richard Hinds 2015 University of South Florida

High-Solids Anaerobic Digestion Of The Organic Fraction Of Municipal Solid Waste State Of The Art, Outlook In Florida, And Enhancing Methane Yields From Lignocellulosic Wastes, Gregory Richard Hinds

USF Tampa Graduate Theses and Dissertations

Anaerobic digestion (AD) is a biotechnology that employs natural microbial metabolism under oxygen-free conditions to stabilize organic waste. AD has been shown to be the most environmentally sustainable technology for treating the organic fraction of municipal solid waste (OFMSW), as it allows for the recovery of energy and nutrients from the waste. AD of OFMSW also saves landfill space and reduces leachate generation and fugitive methane emissions from landfills. High-solids AD (HS-AD) technologies (those designed to process feedstocks with >15% total solids content) have been shown to yield additional benefits when compared with liquid AD (L-AD) for treating OFMSW, including …


Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen 2015 Geosciences Montpellier CNRS/UM2/UMR5243

Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen

Sinkhole Conference 2015

Fluid dynamics in karst systems is complex due to the heterogeneity of hydraulic networks that combine the Porous Fractured Matrix (PFM) and the interconnected drains (CS). These complex dynamic systems often need to be treated as “black boxes” in which only input and output properties are known. In this work, we propose to assess the first-order error induced by considering the temperature as a conservative tracer for flows mixing in karst (fluvio-karst). The fluvio-karstic system is treated as an open thermodynamic system (OTS), which exchanges water and heat with its surrounding. We propose to use a cylindrical PFM drained by …


Numerical Simulation Of Karst Soil Cave Evolution, Long Jia, Yan Meng, Zhende Guan, Lipeng Liu 2015 Institute of Karst Geology and Key Laboratory of Karst Collapse Prevention

Numerical Simulation Of Karst Soil Cave Evolution, Long Jia, Yan Meng, Zhende Guan, Lipeng Liu

Sinkhole Conference 2015

This study is focused on numerical simulation of the formation and development of karst soil caves related to cover-collapse sinkholes. The so-called ‘karst soil cave’ refers to the caves formed in the soil layers above bedrock of sinkhole regions. Because the soil caves are formed and developed under groundwater seepage, studying groundwater level changes can help understand soil cave development and collapse. Based on the improved Terzaghi loosening pressure theory and using excess pore water pressure, two kinds of critical groundwater level decline are discussed. The first, denoted as ∆H0, is the critical groundwater level decline related to soil cave …


Building Codes To Minimize Cover Collapses In Sinkhole-Prone Areas, George Veni, Connie Campbell Brashear, Andrew Glasbrenner 2015 National Cave and Karst Research Institute

Building Codes To Minimize Cover Collapses In Sinkhole-Prone Areas, George Veni, Connie Campbell Brashear, Andrew Glasbrenner

Sinkhole Conference 2015

Cover- collapse sinkholes are forming with increasing frequency under buildings. Analyses of sinkhole distribution in Beacon Woods, Florida, preliminarily indicate their occurrence is an order of magnitude greater in urban versus undeveloped areas, suggesting the structures themselves are enhancing the collapse process. The most likely causes are induced recharge via at least one of two sources. First, runoff and drainage from roads, structures, and impoundments that is not adequately dispersed will promote sinkhole development. Second, leaking water, sewer, and septic systems beneath or adjacent to a structure will also promote collapse. The process of cover-collapse from induced recharge is well …


Hazard Of Sinkhole Flooding To A Cave Hominin Site And Its Control Countermeasures In A Tower Karst Area, South China, Fang Guo, Guanghui Jiang, Kwong Fai Andrew Lo, Qingjia Tang, Yongli Guo, Shaohua Liu 2015 Institute of Karst Geology, Chinese Academy of Geological Sciences

Hazard Of Sinkhole Flooding To A Cave Hominin Site And Its Control Countermeasures In A Tower Karst Area, South China, Fang Guo, Guanghui Jiang, Kwong Fai Andrew Lo, Qingjia Tang, Yongli Guo, Shaohua Liu

Sinkhole Conference 2015

Zengpiyan Cave, one of the most important cave hominin sites of the Neolithic in the South of China, was listed on the national register of cultural preservation sites in 2001. Large quantities of precious material in the Zengpiyan site were unearthed since the beginning of the trial excavation in 1973. These materials include hominin skeletal remains, fire pits, human burials, stone implements, tools fashioned from mollusk shells and animal or plant fossils. According to the historical record, ancient people lived in caves in the karst plain of Guilin. They moved out of the caves approximately 7000 years ago. These cave …


Study On Monitoring And Early Warning Of Karst Collapse Based On Botdr Technique, Zhende Guan 2015 Institute of Karst Geology, CAGS

Study On Monitoring And Early Warning Of Karst Collapse Based On Botdr Technique, Zhende Guan

Sinkhole Conference 2015

Brilliouin Optical Time Domain Reflectometer (BOTDR) is a newly developed measurement and monitoring technique, which utilizes Brilliouin spectroscopy and Optical Time Domain Reflectometer (Jiang et al., 2006; Zhang et al., 2009; Xu et al.,2011) to measure strain generated in optical fibers as distributed in the longitudinal direction. This paper introduces the principle and characters of BOTDR technique firstly, and makes an example of karst collapse monitoring at section K14 of highway from Guilin to Yangshuo. And we talk about how to use this technique in underlying karst collapse monitoring in karst highway, discuss environmental factors, like temperature and vehicle dynamic …


Karst Spring Cutoffs, Cave Tiers, And Sinking Stream Basins Correlated To Fluvial Base Level Decline In South-Central Indiana, Garre A. Conner 2015 Pangea Geoservices

Karst Spring Cutoffs, Cave Tiers, And Sinking Stream Basins Correlated To Fluvial Base Level Decline In South-Central Indiana, Garre A. Conner

Sinkhole Conference 2015

The Mitchell Aquifer averages 80m in thickness and underdrains a karst region in the Crawford Upland and Mitchell Plateau region in south-central Indiana (110,000 km2). The Springville Escarpment is a transitional boundary between the upland and plateau. Cave stream linking between cave tiers in the aquifer and correlation of cave tier inception horizons to a base level decline surface is interpreted for the Kirby Watershed, encompassing the prekarst headland of Indian Creek (42km2). The watershed was severed from lower Indian Creek at Eller Col by limestone cavern drainage on the ridge between White River and East Fork. Correlation of recharge …


Tracer Studies Conducted Nearly Two Decades Apart Elucidate Groundwater Movement Through A Karst Aquifer In The Frederick Valley Of Maryland, Keith A. White, Michael K. Cobb, Thomas Aley, Ethan Weikel 2015 ARCADIS, Inc.

Tracer Studies Conducted Nearly Two Decades Apart Elucidate Groundwater Movement Through A Karst Aquifer In The Frederick Valley Of Maryland, Keith A. White, Michael K. Cobb, Thomas Aley, Ethan Weikel

Sinkhole Conference 2015

A pair of groundwater tracer studies at a single karst test site were completed 18 years apart. The results of these studies have provided evidence of both relatively rapid advective transport via conduits and an extreme capacity for dye storage and retardation. The tracer results, coupled with other subsurface investigation data, are used to develop a conceptual model for groundwater movement through this karst aquifer in the Frederick Valley of Maryland, as well as identify implications for remediation. Three fluorescent tracer dyes used in the initial study were detected in several background monitoring locations established for the second study conducted …


Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell 2015 University of Nebraska-Lincoln

Integration And Delivery Of Interferometric Synthetic Aperture Radar [Insar] Data Into Stormwater Planning Within Karst Terranes, Brian Bruckno, Andrea Vaccari, Edward Hoppe, Scott Acton, Elizabeth Campbell

Department of Earth and Atmospheric Sciences: Faculty Publications

As part of two USDOT-funded studies focused on the development of satellite-based Interferometric Synthetic Aperture Radar (InSAR) technology, the researchers integrated InSAR-derived point cloud data into the transportation design process to optimize the location of a stormwater management system in a karst terrane. After initial validation, the InSAR data (over 1.67 million data points comprising various “scatterers”) were brought into a GIS dataframe and georeferenced to locations of known sinkholes. This dataset was then used to evaluate karst hazard within a 40x40km data frame located in the Valley and Ridge Province of Virginia. The group identified systematic kinematic differences in …


Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang 2015 Institut de Recherche pour le Développement

Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang

Civil and Environmental Engineering Faculty Publications and Presentations

Operational ocean forecast systems provide routine marine products to an ever-widening community of users and stakeholders. The majority of users need information about the quality and reliability of the products to exploit them fully. Hence, forecast centres have been developing improved methods for evaluating and communicating the quality of their products. Global Ocean Data Assimilation Experiment (GODAE) OceanView, along with the Copernicus European Marine Core Service and other national and international programmes, has facilitated the development of coordinated validation activities among these centres. New metrics, assessing a wider range of ocean parameters, have been defined and implemented in real-time. An …


Spatial Variability Of Subsurface Soil Conditions Causing Roadway Settlements, Ömer Bilgin, Kevin Arens, Mark Salveter, Alexander Dettloff 2015 University of Dayton

Spatial Variability Of Subsurface Soil Conditions Causing Roadway Settlements, Ömer Bilgin, Kevin Arens, Mark Salveter, Alexander Dettloff

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Settlement of problematic soils constituting the roadway subgrade may result in pavement distress and structural failure, requiring periodic pavement patching and resurfacing. Many of these problems occur as a result of the settlement of soft cohesive and organic soils. Due to the extent of roadway projects and the limited frequency of boring locations, spatial variability of subsurface soil conditions, and sometimes due to an inadequate extent of exploration, these problematic soils may not be identified suitably during subsurface explorations. An extensive subsurface exploration program was implemented for detailed characterization of subsurface conditions for a relatively short section of an existing …


The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai 2015 Marquette University

The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai

Dissertations (1934 -)

Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …


Comparing Nutrient Recovery Via Rapid (Flash Hydrolysis) And Conventional Hydrothermal Liquefaction Processes For Microalgae Cultivation, Caleb Richard Talbot 2015 Old Dominion University

Comparing Nutrient Recovery Via Rapid (Flash Hydrolysis) And Conventional Hydrothermal Liquefaction Processes For Microalgae Cultivation, Caleb Richard Talbot

Civil & Environmental Engineering Theses & Dissertations

Algal biofuels have the potential to provide a scalable source of renewable fuels in the near future. The high nutrient use in algae cultivation and its recovery and recycling is one of the challenges that may limit the scalability and sustainability of algal biofuels. The present study evaluates the use of Hydrolysate obtained after Flash Hydrolysis (FH) of Scenedesmus at 280 C as a nutrient source for microalgae cultivation. FH Hydrolysate nutrient recycling was compared with low temperature batch Hydrothermal Liquefaction (HTL) nutrient recycling. Oocystis and Scenedesmus were cultivated using Hydrolysate as a partial phosphorous (P) and nitrogen (N) source. …


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