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Articles 1 - 27 of 27
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Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik
Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik
Publications
A reinforced carbon composite can include a carbon substrate and a metal organic framework bonded to the carbon substrate. For example, a reinforced carbon composite can include a first layer, a second layer, and a resin adhered to the first layer and the second layer. The first layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate. The second layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate.
Quantifying Geogrid Reinforcement Mechanism In Roadway Performance Using Cyclic Plate Load (Cpl) Test, G.S. Ellithy, A. Crippa
Quantifying Geogrid Reinforcement Mechanism In Roadway Performance Using Cyclic Plate Load (Cpl) Test, G.S. Ellithy, A. Crippa
Publications
For decades, geogrids have been used successfully to improve performance in both paved and unpaved roadway construction. Even though the current state of practice differentiates between the design methodology incorporating geogrids in paved and unpaved roadways, the true improvement contribution of geogrids is to the base layer, or to the layer that is placed directly on top of it. It has been established that the three reinforcement mechanisms by which geogrids enhance roadway performance are: lateral restraint, bearing capacity increase and membrane tension support. In order to quantify these mechanisms and their contribution to the roadway performance improvement, two Cyclic …
Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik
Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik
Publications
A reinforced carbon composite can include a carbon substrate and a metal organic framework bonded to the carbon substrate. For example, a reinforced carbon composite can include a first layer, a second layer, and a resin adhered to the first layer and the second layer. The first layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate. The second layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate.
Using Machine Learning In Estimating Changing Bed Shear Over A Flume Test Box, Ghada S. Ellithy, Siddharth S. Parida
Using Machine Learning In Estimating Changing Bed Shear Over A Flume Test Box, Ghada S. Ellithy, Siddharth S. Parida
Publications
A dam or levee breach caused by overflow erosion is difficult to evaluate during an overtopping event due to difficulty in accessibility and quickly changing conditions. However, for assessment of risk associated with breach time and ensuing downstream consequences, the erosion rate of embankment soils during this process needs to be evaluated. Soil erosion and water depth measurements were taken during flume tests using a Shallow Water Lidar (SWL) system scans. The tests were conducted in a 1-m-wide tilting flume on three cleans and gravel soil mixes with a median grain size D50of 2, 5,and 20 mm. The box measured …
The Breathing Human Infrastructure: Integrating Air Quality, Traffic, And Social Media Indicators, Heather O'Leary, Scott Parr, Marwa El-Sayed
The Breathing Human Infrastructure: Integrating Air Quality, Traffic, And Social Media Indicators, Heather O'Leary, Scott Parr, Marwa El-Sayed
Publications
Outdoor air pollution is a complex system that is responsible for the deaths of millions of people annually, yet the integration of interdisciplinary data necessary to assess air quality's multiple metrics is still lacking. This case study integrates atmospheric indicators (concentrations of criteria pollutants including particulate matter and gaseous pollutants), traffic indicators (permanent traffic monitoring station data), and social indicators (community responses in Twitter archives) representing the interplay of the three critical pillars of the United Nations' Triple Bottom Line: environment, economy, and society. During the watershed moment of the COVID-19 pandemic lockdowns in Florida, urban centers demonstrated the gaps …
Cross Domain Iw Threats To Sof Maritime Missions: Implications For U.S. Sof, Gary C. Kessler, Diane M. Zorri
Cross Domain Iw Threats To Sof Maritime Missions: Implications For U.S. Sof, Gary C. Kessler, Diane M. Zorri
Publications
As cyber vulnerabilities proliferate with the expansion of connected devices, wherein security is often forsaken for ease of use, Special Operations Forces (SOF) cannot escape the obvious, massive risk that they are assuming by incorporating emerging technologies into their toolkits. This is especially true in the maritime sector where SOF operates nearshore in littoral zones. As SOF—in support to the U.S. Navy— increasingly operate in these contested maritime environments, they will gradually encounter more hostile actors looking to exploit digital vulnerabilities. As such, this monograph comes at a perfect time as the world becomes more interconnected but also more vulnerable.
Case Study: Unsaturated Embankment Failure On Soft Soils, Ghada Ellithy, Timothy D. Stark
Case Study: Unsaturated Embankment Failure On Soft Soils, Ghada Ellithy, Timothy D. Stark
Publications
This paper describes the application of unsaturated soil mechanics to an interstate connecting-ramp embankment that failed during construction. Specifically, matric suction is incorporated into the calculation of the tension crack (TC) depth induced by desiccation and strain incompatibility and the contribution of matric suction to embankment shear strength. The results are compared with field observations to assess the viability of unsaturated soil mechanics in modeling compacted embankments in stability analyses. Results from this study suggest that using unsaturated shear strength parameters while introducing a TC in the compacted fill yields a reasonable inverse analysis of this interstate embankment. This may …
Monte Carlo Simulations Of Coupled Transient Seepage Flow And Compressive Stress In Levees, Fred Thomas Tracy, Ghada Ellithy, Jodi L. Ryder, Martin T. Schultz, Benjamin R. Breland, T. Chris Massey, Maureen K. Corcoran
Monte Carlo Simulations Of Coupled Transient Seepage Flow And Compressive Stress In Levees, Fred Thomas Tracy, Ghada Ellithy, Jodi L. Ryder, Martin T. Schultz, Benjamin R. Breland, T. Chris Massey, Maureen K. Corcoran
Publications
The purpose of this research is to compare the results from two different computer programs of flow analyses of two levees at Port Arthur, Texas where rising water of a flood from Hurricane Ike occurred on the levees. The first program (Program 1) is a two-dimensional (2-D) transient finite element program that couples the conservation of mass flow equation with accompanying hydraulic boundary conditions with the conservation of force equations with accompanying x and y displacement and force boundary conditions, thus yielding total head, x displacement, and y displacement as unknowns at each finite element node. The second program (Program …
Thermodynamic Model Of Co2 Deposition In Cold Climates, Sandra K. S. Boetcher, Ted Von Hippel, Matthew J. Traum
Thermodynamic Model Of Co2 Deposition In Cold Climates, Sandra K. S. Boetcher, Ted Von Hippel, Matthew J. Traum
Publications
A thermodynamic model, borrowing ideas from psychrometric principles, of a cryogenic direct-air CO2-capture system utilizing a precooler is used to estimate the optimal CO2 removal fraction to minimize energy input per tonne of CO2. Energy costs to operate the system scale almost linearly with the temperature drop between the ingested air and the cryogenic desublimation temperature of CO2, driving siting to the coldest accessible locations. System performance in three Arctic/Antarctic regions where the proposed system can potentially be located is analyzed. Colder ambient temperatures provide colder system input air temperature yielding lower CO2 removal energy requirements. A case is also …
Integrating Field Monitoring And Numerical Modeling To 3 Evaluate Performance Of A Levee Under 4 Climatic And Tidal Variations, Xavier A. Rivera-Hernandez, Ghada Ellithy, Farshid Vahedifard
Integrating Field Monitoring And Numerical Modeling To 3 Evaluate Performance Of A Levee Under 4 Climatic And Tidal Variations, Xavier A. Rivera-Hernandez, Ghada Ellithy, Farshid Vahedifard
Publications
Several short-duration and extreme hydraulic loadings impose time-dependent variably saturated seepage conditions on earthen 7 slopes and embankments. Difficulty assigning appropriate input parameters and lack of full-scale validation are among the main factors 8 introducing uncertainty and lack of confidence when performing numerical transient seepage analysis. This case study demonstrates how 9 to effectively use field-monitoring data to improve the numerical analysis of a levee under climatic and tidal variations. The case study 10 includes a silty sand setback levee located near Seattle. An array of tensiometers and soil moisture sensors installed within the levee’s embank11 ment and foundation, along …
Meshless Modeling Of Flow Dispersion And Progressive Piping In Poroelastic Levees, Anthony Khoury, Eduardo Divo, Alain J. Kassab, Sai Kakuturu, Lakshmi Reddi
Meshless Modeling Of Flow Dispersion And Progressive Piping In Poroelastic Levees, Anthony Khoury, Eduardo Divo, Alain J. Kassab, Sai Kakuturu, Lakshmi Reddi
Publications
Performance data on earth dams and levees continue to indicate that piping is one of the major causes of failure. Current criteria for prevention of piping in earth dams and levees have remained largely empirical. This paper aims at developing a mechanistic understanding of the conditions necessary to prevent piping and to enhance the likelihood of self-healing of cracks in levees subjected to hydrodynamic loading from astronomical and meteorological (including hurricane storm surge-induced) forces. Systematic experimental investigations are performed to evaluate erosion in finite-length cracks as a result of transient hydrodynamic loading. Here, a novel application of the localized collocation …
Erosion Rate Equations For Coarse- Grained Materials Using A Small Flume Testing, Ghada Ellithy, Johannes L. Wibowo, Maureen K. Corcoran
Erosion Rate Equations For Coarse- Grained Materials Using A Small Flume Testing, Ghada Ellithy, Johannes L. Wibowo, Maureen K. Corcoran
Publications
Erosion rate of soils during a levee or dam overtopping event is a major component in risk assessment evaluation of breach time and consequently in determining the downstream consequences. There is uncertainty in estimation of the erosion rate especially for coarsegrained materials that comprise the outer shell layer of dams as well as homogenous levees that are constructed of such materials. In this paper, erosion rate results are presented on three soil mixes that share the same median grain size D50 of 2 mm, the fines content varies between zero and 20%, and the gravel content between zero and 30%. …
Does Length Of Ride, Gender Or Nationality Affect Willingness To Ride In A Driverless Ambulance?, Stephen Rice, Scott R. Winter, Rian Mehta, Joseph R. Keebler, Bradley S. Baugh, Emily C. Anania, Mattie N. Milner
Does Length Of Ride, Gender Or Nationality Affect Willingness To Ride In A Driverless Ambulance?, Stephen Rice, Scott R. Winter, Rian Mehta, Joseph R. Keebler, Bradley S. Baugh, Emily C. Anania, Mattie N. Milner
Publications
Due to the frequent lack of ambulances and personnel, the purpose of this study was to examine consumers’ willingness-to-ride in an ambulance that was either driven by a human driver or completely automated (with no human driver) based on the gender of the participant and their nationality, either Indian or American. A two-study experimental design was utilized using over 1,000 participants. In Study 1, the length of the ride and the type of driver were manipulated while in Study 2, the length of the ride was manipulated across genders and nationality. Study 2 also collected affect measures to complete a …
Determination Of Erosion Parameters Of Coarse-Grained Materials Using A Small Flume, Ghada S. Ellithy, Johannes L. Wibowo, Maureen K. Corcoran
Determination Of Erosion Parameters Of Coarse-Grained Materials Using A Small Flume, Ghada S. Ellithy, Johannes L. Wibowo, Maureen K. Corcoran
Publications
Overtopping is one of the major causes of dams and levees failure. There is uncertainty in estimation of the erosion parameters especially for coarse- grained materials that comprise the outer shell layer of dams as well as homogenous levees that are constructed of such materials. In this paper, results from a box test performed on three coarse grained materials in a 0.3-meter wide flume are discussed. The three materials share the same median grain size D50 of 2 mm, however, they vary in fines content between zero to 20%. The box measured 0.3 m wide x 0.6 m long x …
The Effects Of Isoprene And Nox On Secondary Organic Aerosols Formed Through Reversible And Irreversible Uptake To Aerosol Water, Marwa M. El-Sayed, Diana L. Ortiz-Montalvo, Christopher J. Hennigan
The Effects Of Isoprene And Nox On Secondary Organic Aerosols Formed Through Reversible And Irreversible Uptake To Aerosol Water, Marwa M. El-Sayed, Diana L. Ortiz-Montalvo, Christopher J. Hennigan
Publications
Isoprene oxidation produces water-soluble organic gases capable of partitioning to aerosol liquid water. The formation of secondary organic aerosols through such aqueous pathways (aqSOA) can take place either reversibly or irreversibly; however, the split between these fractions in the atmosphere is highly uncertain. The aim of this study was to characterize the reversibility of aqSOA formed from isoprene at a location in the eastern United States under substantial influence from both anthropogenic and biogenic emissions. The reversible and irreversible uptake of water-soluble organic gases to aerosol water was characterized in Baltimore, Maryland, USA, using measurements of particulate water-soluble organic carbon …
Highly Vented Truss Wall Honeycomb Structures, David J. Sypeck
Highly Vented Truss Wall Honeycomb Structures, David J. Sypeck
Publications
A vented honeycomb structure with a plurality of honeycomb cells arranged in a hierarchical order and having a plurality of truss walls, each truss wall including a plurality of members. The vented honeycomb structure is fabricated by joining a plurality of sheets of trusses using any one of an expansion, a corrugation, and a slotting process. Fabrication can also occur by deposition, casting, additive, extrusion, or aligning and joining methods. The honeycomb cells, truss walls, truss wall openings, and truss wall members can be functionally graded.
Influence Of Activated Carbon Surface Oxygen Functionality On Elemental Mercury Adsorption From Aqueous Solution, Emily K. Faulconer, David W. Mazyck
Influence Of Activated Carbon Surface Oxygen Functionality On Elemental Mercury Adsorption From Aqueous Solution, Emily K. Faulconer, David W. Mazyck
Publications
Mercury (Hg), though naturally occurring, is a toxic element. Exposure to various forms of mercury can be harmful for humans and ecosystems. Mercury-contaminated wastewater can be treated using activated carbon to adsorb the mercury, allowing for safe discharge. Wet chemical oxidation of activated carbon was performed to enhanced surface oxygen functionality, with the objective of enhancing aqueous ionic (Hg(II)) and elemental (Hg(0)) mercury adsorption. Characterization of the modified carbons included nitrogen adsorption-desorption, elemental analysis, point of zero charge, and total acidity titration. The concentration and identity of the modifying reagent influenced the characteristics of the carbons, including the surface oxygen …
A Spreadsheet For Estimating Soil Water Characteristic Curves (Swcc), Ghada Ellithy
A Spreadsheet For Estimating Soil Water Characteristic Curves (Swcc), Ghada Ellithy
Publications
SWCC can be measured in the lab; however, due to the cost, time, and high variability in the results, empirical equations were developed using multiple regression approaches on databases consisting of a large number of measured SWCCs. The spreadsheet presented herein utilizes different methods that use basic soil properties, such as grain size distribution and Atterberg limits, to calculate the input parameters for van Genuchten and Fredlund and Xing equations. These parameters are required by numerical models, such as SEEP/W, to perform transient seepage analysis. The spreadsheet allows copying the generated curve data points as well as an input into …
Evaluating The Mechanisms Of Erosion For Coarse-Grained Materials, Maureen K. Corcoran, Ghada Ellithy, Michael K. Sharp, Johannes L. Wibowo
Evaluating The Mechanisms Of Erosion For Coarse-Grained Materials, Maureen K. Corcoran, Ghada Ellithy, Michael K. Sharp, Johannes L. Wibowo
Publications
Efforts are currently underway by the U.S. Army Corps of Engineers (USACE) to perform a risk assessment of all dams and levees within their portfolio. The vast majority of that portfolio is earthen structures. Findings from the assessments have shown that the major risk drivers for these earth structures are related to erosion (internal and external), overtopping, poorly designed and constructed intrusions (such as pipe crossings), and other factors to a lesser degree (such as burrowing animals). Therefore, the USACE is currently investigating several of these failure modes with emphasis on internal and external erosion. This paper will highlight efforts …
Direct Atmospheric Evidence For The Irreversible Formation Of Aqueous Secondary Organic Aerosol, Marwa M. El-Sayed, Yingqing Wang, Christopher J. Hennigan
Direct Atmospheric Evidence For The Irreversible Formation Of Aqueous Secondary Organic Aerosol, Marwa M. El-Sayed, Yingqing Wang, Christopher J. Hennigan
Publications
The reversible nature of aqueous secondary organic aerosol (aqSOA) formation was characterized for the first time through direct atmospheric measurements. Water-soluble organic carbon in the gas and particle phases (WSOCg and WSOCp) was measured simultaneously to quantify aqSOA formation in Baltimore, Maryland. During the nighttime, aqSOA formation was evident as WSOCg increasingly partitioned to the particle phase with increasing relative humidity (RH). To characterize the reversible/irreversible nature of this aqSOA, the WSOCp measurement was alternated through an unperturbed ambient channel and through a “dried” channel maintained at ~40% RH (with 7 s residence time) to mimic the natural drying particles …
Comparison Of Lock-In And Pulse-Phase Thermography For Defect Characterization In Frp Composites Applied To Concrete, Jeff Brown, Sai Harsha Chittineni
Comparison Of Lock-In And Pulse-Phase Thermography For Defect Characterization In Frp Composites Applied To Concrete, Jeff Brown, Sai Harsha Chittineni
Publications
Thermal imaging is a well-established technique for the non-destructive evaluation of FRP composites applied to reinforced concrete. Defect characterization using IR thermography, however, remains a topic of on-going research, and there are currently no universally accepted standards for data collection or interpretation. This research involved large scale thermography inspection of two FRP strengthened bridge girders that were removed from service after approximately 10 years of service in a potentially corrosive marine environment. Trial inspections were performed on test areas where defects could be identified using sounding methods. Two procedures showed the most promise for identifying and characterizing defects: sinusoidal (lock-in …
Reduction Of Transportation Greenhouse Gas Emissions To Mitigate Climate Change Impacts, Mary Snow, Richard Snow
Reduction Of Transportation Greenhouse Gas Emissions To Mitigate Climate Change Impacts, Mary Snow, Richard Snow
Publications
Weather affects almost all modes of transportation in a modern society, and likewise, transportation has an enormous impact on the weather. Transportation greenhouse gas emissions (GHG) impact climate change, which impacts transportation in return. Reduction of transportation impacts on climate change can mitigate the reverse climate change impacts on transportation. This paper examines the relationship between transportation and climate change and establishes prospective solutions to reduce transportation greenhouse gas emission impacts on climate change and mitigate the reverse climate change impacts on transportation.
The 6th Mode Of Transportation, Robert O. Walton
The 6th Mode Of Transportation, Robert O. Walton
Publications
The five modes of freight transportation are normally characterized as motor carriers, railroads, airlines, water carriers, and pipelines. This paper will attempt to position the Internet as the sixth mode of transportation. This paper compares the strengths and weaknesses of the traditional five modes of transportation against the proposed 6th mode of the Internet. Without including the Internet as a mode of transportation, and tracking the economic value that it adds to the economy, the economic impact of the Internet as a mode is not considered. The recommendation of this study is that the Internet should be added to the …
Addressing Water Quality Issues In Rural Cameroon With Household Biosand Filters, Laine Klopfensten, Laura Petrasky, Valerie Winton, Jeff Brown
Addressing Water Quality Issues In Rural Cameroon With Household Biosand Filters, Laine Klopfensten, Laura Petrasky, Valerie Winton, Jeff Brown
Publications
This paper describes an ongoing collaboration between the Hope College student chapter of Engineers Without Borders – USA and the rural community of Nkuv in the Northwest Province of Cameroon related to improving drinking water quality using Manz biosand filters. The collaboration began in 2006 and focused on developing a community-based construction and distribution model for household water treatment units. Results from microbiology testing of the constructed filters indicate that this water treatment method is effective for improving water quality in rural areas. The results also highlight the need for ongoing assessment and adapting community education programs to provide necessary …
Internet Enabled Remote Driving Of A Combat Hybrid Electric Power System For Duty Cycle Measurement, Jarrett Goodell, Marc Compere, Wilford Smith, Mark Brudnak, Mike Pozolo, Et Al.
Internet Enabled Remote Driving Of A Combat Hybrid Electric Power System For Duty Cycle Measurement, Jarrett Goodell, Marc Compere, Wilford Smith, Mark Brudnak, Mike Pozolo, Et Al.
Publications
This paper describes a human-in-the-loop motion-based simulator interfaced to hybrid-electric power system hardware, both of which were used to measure the duty cycle of a combat vehicle in a virtual simulation environment. The project discussed is a greatly expanded follow-on to the experiment published in [1,7]. This paper is written in the context of [1,7] and therefore highlights the enhancements. The most prominent of these enhancements is the integration (in real-time) of the Power & Energy System Integration Lab (P&E SIL) with a motion base simulator by means of a “long haul” connection over the Internet (a geographical distance of …
Heating Methods And Detection Limits For Infrared Thermography Inspection Of Fiber-Reinforced Polymer Composites, Jeff R. Brown, H. R. Hamilton
Heating Methods And Detection Limits For Infrared Thermography Inspection Of Fiber-Reinforced Polymer Composites, Jeff R. Brown, H. R. Hamilton
Publications
The use of fiber-reinforced polymer (FRP) composites to strengthen existing civil infrastructure is expanding rapidly. Many FRP systems used to strengthen reinforced concrete are applied using a wet lay-up method in which dry fibers are saturated on site and then applied to the surface. This research investigated using infrared thermography (IRT) as a nondestructive evaluation (NDE) tool for detecting air voids and epoxy-filled holes in FRP systems bonded to a concrete substrate. Four small-scale specimens with FRP thicknesses ranging from 1 to 4 mm (0.04 to 0.16 in.) containing fabricated defects were constructed and inspected in a laboratory setting. Three …
Modeling Bus Priority Using Intermodal Dynamic Network Assignment-Simulation Methodology, Khaled F. Abdelghany, Ahmed F. Abdelghany, Hani S. Mahmassani, Akmal S. Abdelfatah
Modeling Bus Priority Using Intermodal Dynamic Network Assignment-Simulation Methodology, Khaled F. Abdelghany, Ahmed F. Abdelghany, Hani S. Mahmassani, Akmal S. Abdelfatah
Publications
This article presents a modeling framework that represents bus priority at signalized intersections in the context of its potential network-level and intermodal effects. The model incorporates bus priority within an intermodal dynamic traffic assignment simulation model. It dynamically assigns travelers to different modes and routes in the network according to prevailing traffic conditions, which result from applying a certain network control/bus priority scheme. The model considers changes in traffic conditions as a result of (1) drivers’ route choice adjustments due to changes in traffic signals settings and (2) modal shifts by travelers to take advantage of improved transit service. Three …