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Civil and Environmental Engineering
Civil and Environmental Engineering Faculty Publications and Presentations
- Keyword
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- Climatic changes (2)
- Tides (2)
- Acid-base chemistry (1)
- Algorithms (1)
- Altimetry (1)
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- Altitudes--Measurement (1)
- Atmospheric chemistry (1)
- Atmospheric models (1)
- Cape Fear River Estuary (N.C.) (1)
- Choice of transportation -- Research -- Oregon -- Portland Metropolitan Area (1)
- Columbia River (Or. And Wash.) -- Tides -- Analysis (1)
- Columbia River Estuary (Or. and Wash.) (1)
- Columbia River Estuary (Or. and Wash.) -- Ecology (1)
- Columbia River Estuary (Or. and Wash.) -- Environmental conditions (1)
- Cryosphere (1)
- Data Collection -- methods -- United States (1)
- Deltas -- Environmental aspects (1)
- Electronic traffic controls -- Performance -- Measurement (1)
- Environmental impact analysis (1)
- Estuaries -- Hydrodynamics (1)
- Estuarine sediments -- Mathematical models (1)
- Hydrologic models (1)
- Hydrology -- Mathematical models (1)
- Laser Doppler velocimetry (1)
- Machine learning (1)
- Mice (Computers) (1)
- Models & modelmaking (1)
- Nanostructured materials (1)
- Nanotechnology (1)
- North Atlantic Ocean -- Climate (1)
Articles 1 - 18 of 18
Full-Text Articles in Entire DC Network
A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov
A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov
Civil and Environmental Engineering Faculty Publications and Presentations
Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment …
Safety Effectiveness Of Pedestrian Crossing Enhancements, Christopher M. Monsere, Miguel Figliozzi, Sirisha Kothuri, Ali Razmpa, Daniel R. Hazel
Safety Effectiveness Of Pedestrian Crossing Enhancements, Christopher M. Monsere, Miguel Figliozzi, Sirisha Kothuri, Ali Razmpa, Daniel R. Hazel
Civil and Environmental Engineering Faculty Publications and Presentations
Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were collected on 191 crossings. Supplemental data items included crossing location information, route characteristics, surrounding land use and crossing enhancement descriptions. Pedestrian volume at the crossing locations was a highly desirable but unavailable data element. To characterize pedestrian activity, a method was developed to estimate ranges for pedestrian crosswalk activity levels based on the land use classification at the census block level and the presence …
Laser Doppler Velocimetry Using A Modified Computer Mouse, Edward D. Zaron
Laser Doppler Velocimetry Using A Modified Computer Mouse, Edward D. Zaron
Civil and Environmental Engineering Faculty Publications and Presentations
A computer mouse has been modified for use as a low-cost laser Doppler interferometer and used to measure the two-component fluid velocity of a flowing soap film. The mouse sensor contains two vertical cavity surface emitting lasers, photodiodes, and signal processing hardware integrated into a single package, approximately 1 cm2 in size, and interfaces to a host computer via a standard USB port. Using the principle of self-mixing interferometry, whereby laser light re-enters the laser cavity after being scattered from a moving target, the Doppler shift and velocity of scatterers dispersed in the flow are measured. Observations of the boundary …
Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer
Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer
Civil and Environmental Engineering Faculty Publications and Presentations
Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland …
Multiple New-Particle Growth Pathways Observed At The Us Doe Southern Great Plains Field Site, Anna L. Hodshire, Michael J. Lawler, Jun Zhao, John Ortega, Coty Jen, Taina Yli-Juuti, Jared F. Brewer, Jack K. Kodros, Kelley C. Barsanti, Dave R. Hanson, Peter H. Mcmurry, James N. Smith, Jeffery R. Pierce
Multiple New-Particle Growth Pathways Observed At The Us Doe Southern Great Plains Field Site, Anna L. Hodshire, Michael J. Lawler, Jun Zhao, John Ortega, Coty Jen, Taina Yli-Juuti, Jared F. Brewer, Jack K. Kodros, Kelley C. Barsanti, Dave R. Hanson, Peter H. Mcmurry, James N. Smith, Jeffery R. Pierce
Civil and Environmental Engineering Faculty Publications and Presentations
New-particle formation (NPF) is a significant source of aerosol particles into the atmosphere. However, these particles are initially too small to have climatic importance and must grow, primarily through net uptake of low volatility species, from diameters ∼ 1 to 30–100 nm in order to potentially impact climate. There are currently uncertainties in the physical and chemical processes associated with the growth of these freshly formed particles that lead to uncertainties in aerosol-climate modeling. Four main pathways for new-particle growth have been identified: condensation of sulfuric-acid vapor (and associated bases when available), condensation of organic vapors, uptake of organic acids …
Controls On Turbulent Mixing In A Strongly Stratified And Sheared Tidal River Plume, Joseph T. Jurisa, Jonathan Nash, James N. Moum, Levi F. Kilcher
Controls On Turbulent Mixing In A Strongly Stratified And Sheared Tidal River Plume, Joseph T. Jurisa, Jonathan Nash, James N. Moum, Levi F. Kilcher
Civil and Environmental Engineering Faculty Publications and Presentations
Considerable effort has been made to parameterize turbulent kinetic energy (TKE) dissipation rate εand mixing in buoyant plumes and stratified shear flows. Here, a parameterization based on Kunze et al. is examined, which estimates ε as the amount of energy contained in an unstable shear layer (Ri < Ric) that must be dissipated to increase the Richardson number Ri = N2/S2 to a critical value Ric within a turbulent decay time scale. Observations from the tidal Columbia River plume are used to quantitatively assess the relevant parameters controlling ε over a range of tidal …
On The Observability Of Bottom Topography From Measurements Of Tidal Sea Surface Height, Edward D. Zaron
On The Observability Of Bottom Topography From Measurements Of Tidal Sea Surface Height, Edward D. Zaron
Civil and Environmental Engineering Faculty Publications and Presentations
of whether features of the ocean bottom topography can be identified from measurements of water level is investigated using a simplified one-dimensional barotropic model. Because of the nonlinear dependence of the sea surface height on the water depth, a linearized analysis is performed concerning the identification of a Gaussian bump within two specific depth profiles, (1) a constant depth domain, and, (2) a constant depth domain adjoining a near-resonant continental shelf. Observability is quantified by examining the estimation error in a series of identical-twin experiments varying data density, tide wavelength, assumed (versus actual) topographic correlation scale, and friction. For measurements …
Tidal River Dynamics: Implications For Deltas, Ton Hoitink, David A. Jay
Tidal River Dynamics: Implications For Deltas, Ton Hoitink, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
Tidal rivers are a vital and little studied nexus between physical oceanography and hydrology. It is only in the last few decades that substantial research efforts have been focused on the interactions of river discharge with tidal waves and storm surges into regions beyond the limit of salinity intrusion, a realm that can extend inland hundreds of kilometers. One key phenomenon resulting from this interaction is the emergence of large fortnightly tides, which are forced long waves with amplitudes that may increase beyond the point where astronomical tides have become extinct. These can be larger than the linear tide itself …
Century-Long Variability And Trends In Daily Precipitation Characteristics At Three Finnish Stations, Masoud Irannezhad, Hannu Marttila, Chen De-Liang, Bjørn Kløve
Century-Long Variability And Trends In Daily Precipitation Characteristics At Three Finnish Stations, Masoud Irannezhad, Hannu Marttila, Chen De-Liang, Bjørn Kløve
Civil and Environmental Engineering Faculty Publications and Presentations
Long-term variations and trends in a wide range of statistics for daily precipitation characteristics in terms of intensity, frequency and duration in Finland were analysed using precipitation records during 1908－2008 from 3 meteorological stations in the south (Kaisaniemi), center (Kajaani) and north (Sodankylä). Although precipitation days in northern part were more frequent than in central and southern parts, daily precipitation intensity in the south was generally higher than those in the centre and north of the country. Annual sum of very light precipitation (0 mm < daily precipitation ≤ long-term 50th percentile of daily precipitation more than 0 mm) significantly (p
Estimating River Discharge Using Multiple-Tide Gauges Distributed Along A Channel, Hamed R. Moftakhari, David A. Jay, Stefan Talke
Estimating River Discharge Using Multiple-Tide Gauges Distributed Along A Channel, Hamed R. Moftakhari, David A. Jay, Stefan Talke
Civil and Environmental Engineering Faculty Publications and Presentations
Reliable estimation of freshwater inflow to the ocean from large tidal rivers is vital for water resources management and climate analyses. Discharge gauging stations are typically located beyond the tidal intrusion reach, such that inputs and losses occurring closer to the ocean are not included. Here, we develop a method of estimating river discharge using multiple gauges and time-dependent tidal statistics determined via wavelet analysis. The Multiple-gauge Tidal Discharge Estimate (MTDE) method is developed using data from the Columbia River and Fraser River estuaries and calibrated against river discharge. Next, we evaluate the general applicability of MTDE by testing an …
A Novel Methodology For Spatial Damage Detection And Imaging Using A Distributed Carbon Nanotube-Based Composite Sensor Combined With Electrical Impedance Tomography, Hongbo Dai, Gerard J. Gallo, Thomas Schumacher, Erik T. Thostenson
A Novel Methodology For Spatial Damage Detection And Imaging Using A Distributed Carbon Nanotube-Based Composite Sensor Combined With Electrical Impedance Tomography, Hongbo Dai, Gerard J. Gallo, Thomas Schumacher, Erik T. Thostenson
Civil and Environmental Engineering Faculty Publications and Presentations
This paper describes a novel non-destructive evaluation methodology for imaging of damage in composite materials using the electrical impedance tomography (EIT) technique applied to a distributed carbon nanotube-based sensor. The sensor consists of a nonwoven aramid fabric, which was first coated with nanotubes using a solution casting approach and then infused with epoxy resin through the vacuum assisted resin transfer molding technique. Finally, this composite sensor is cured to become a mechanically-robust, electromechanically-sensitive, and highly customizable distributed two-dimensional sensor which can be adhered to virtually any substrate. By assuming that damage on the sensor directly affects its conductivity, a difference …
Hydrologic Modeling In Dynamic Catchments: A Data Assimilation Approach, Sahani Darshika Pathiraja, Ashish Sharma, Lucy Marshall, Hamid Moradkhani
Hydrologic Modeling In Dynamic Catchments: A Data Assimilation Approach, Sahani Darshika Pathiraja, Ashish Sharma, Lucy Marshall, Hamid Moradkhani
Civil and Environmental Engineering Faculty Publications and Presentations
The transferability of conceptual hydrologic models in time is often limited by both their structural deficiencies and adopted parameterizations. Adopting a stationary set of model parameters ignores biases introduced by the data used to derive them, as well as any future changes to catchment conditions. Although time invariance of model parameters is one of the hallmarks of a high quality hydrologic model, very few (if any) models can achieve this due to their inherent limitations. It is therefore proposed to consider parameters as potentially time varying quantities, which can evolve according to signals in hydrologic observations. In this paper, we …
Traser: A Traffic Signal Event-Based Recorder, Chenhui Liu, Anuj Sharma, Edward Smaglik, Sirisha Kothuri
Traser: A Traffic Signal Event-Based Recorder, Chenhui Liu, Anuj Sharma, Edward Smaglik, Sirisha Kothuri
Civil and Environmental Engineering Faculty Publications and Presentations
In the past decades, the demand for high-resolution event-based traffic signal indication and detector data has increased due to the need for the collection and reporting of performance measures. This paper will first lay a groundwork for why this type of data acquisition is important, followed by the introduction of a new low-cost, user-friendly, high-resolution traffic signal event-based recorder—TraSER, with integrated video. This paper describes TraSER’s structure, operating principles, and field applications. TraSER allows researchers to be able to collect high-resolution event-based controller data at signalized intersections easily and conveniently. The paper concludes with a discussion on future expansion of …
Do Characteristics Of Walkable Environments Support Bicycling? Toward A Definition Of Bicycle-Supported Development, Christopher D. Muhs, Kelly Clifton
Do Characteristics Of Walkable Environments Support Bicycling? Toward A Definition Of Bicycle-Supported Development, Christopher D. Muhs, Kelly Clifton
Civil and Environmental Engineering Faculty Publications and Presentations
Does walkability equate with bikeability? Through a comprehensive review of studies of the built environment and bicycling, including mode choice, route choice, safety, and urban design literature, this paper addresses this question. Previous work has raised the issue that the two modes are functionally different, despite them often being combined into a nonmotorized category, and has highlighted research challenges. Existing studies of bikeability have largely focused on infrastructure. This paper contributes to the literature on bicycling and the built environment by providing a thorough review of past research with a focus on the relationships between land use, urban form, and …
Identification And Reduction Of Retracker-Related Noise In Altimeter-Derived Sea Surface Height Measurements, Edward D. Zaron, Robert Decarvalho
Identification And Reduction Of Retracker-Related Noise In Altimeter-Derived Sea Surface Height Measurements, Edward D. Zaron, Robert Decarvalho
Civil and Environmental Engineering Faculty Publications and Presentations
Data from the Jason-2 calibration/validation mission phase have been analyzed to identify the correlation between sea surface height (SSH) and significant wave height (SWH) errors.A cross-spectral analysis indicates that the SSH and SWH errors are nearly white and significantly correlated at scales from 12 to 100 km, consistent with the hypothesized error source, the waveform retracker. Because of the scale separation between the SWH signal and noise, it is possible to correct the SSH data by removing the SSH noise correlated with the SWH noise. Such a correction has been implemented using the empirical correlation found during the Jason-2 calibration …
The Effect Of Channel Deepening On Tides And Storm Surge: A Case Study Of Wilmington, Nc, R. Familkhalili, Stefan A. Talke
The Effect Of Channel Deepening On Tides And Storm Surge: A Case Study Of Wilmington, Nc, R. Familkhalili, Stefan A. Talke
Civil and Environmental Engineering Faculty Publications and Presentations
In this study we investigate the hypothesis that increasing channel depth in estuaries can amplify both tides and storm surge by developing an idealized numerical model representing the 1888, 1975, and 2015 bathymetric conditions of the Cape Fear River Estuary, NC. Archival tide gauge data recovered from the U.S. National Archives indicates that mean tidal range in Wilmington has doubled to 1.55m since the 1880s, with a much smaller increase of 0.07mobserved near the ocean boundary. These tidal changes are reproduced by simulating channel depths of 7m (1888 condition) and 15.5m (modern condition). Similarly, model sensitivity studies using idealized, parametric …
Utilizing High Resolution Bus Gps Data To Visualize And Identify Congestion Hot-Spots In Urban, Nicholas B. Stoll, Travis B. Glick, Miguel Figliozzi
Utilizing High Resolution Bus Gps Data To Visualize And Identify Congestion Hot-Spots In Urban, Nicholas B. Stoll, Travis B. Glick, Miguel Figliozzi
Civil and Environmental Engineering Faculty Publications and Presentations
Congestion and travel delay on urban roadways can influence the roadways’ operating costs and service attractiveness. This research used high-resolution bus data to examine sources of delay on urban arterials. A set of tools was created to help visualize trends in bus behavior and movement; these tools allowed larger traffic trends to be visualized along urban corridors and streets. With buses as probes and examining aggregated bus behavior, contoured speed plots were used to understand the behavior of roadways outside the zone of influence of bus stops. Speed plots were used to discover trends and travel patterns with only a …
M2 Internal Tides And Their Observed Wavenumber Spectra From Satellite Altimetry, Richard D. Ray, Edward D. Zaron
M2 Internal Tides And Their Observed Wavenumber Spectra From Satellite Altimetry, Richard D. Ray, Edward D. Zaron
Civil and Environmental Engineering Faculty Publications and Presentations
A near-global chart of surface elevations associated with the stationary M2 internal tide is empirically constructed from multimission satellite altimeter data. An advantage of a strictly empirical mapping approach is that results are independent of assumptions about ocean wave dynamics and, in fact, can be used to test such assumptions. A disadvantage is that present-day altimeter coverage is only marginally adequate to support mapping such short-wavelength features. Moreover, predominantly north–south ground-track orientations and contamination from nontidal oceanographic variability can lead to deficiencies in mapped tides. Independent data from Cryosphere Satellite-2 (CryoSat-2) and other altimeters are used to …