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Full-Text Articles in Engineering

Sea Level Rise And The Drivers Of Daily Water Levels In The Sacramento-San Joaquin Delta, H. Baranes, Steven Dykstra, D. A. Jay, S. A. Talke Dec 2023

Sea Level Rise And The Drivers Of Daily Water Levels In The Sacramento-San Joaquin Delta, H. Baranes, Steven Dykstra, D. A. Jay, S. A. Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Water levels in deltas and estuaries vary on multiple timescales due to coastal, hydrologic, meteorologic, geologic, and anthropogenic factors. These diverse factors increase the uncertainty of, and may bias, relative sea level rise (RSLR) estimates. Here, we evaluate RSLR in San Francisco Bay and the Sacramento-San Joaquin Delta, USA by applying a physics-based, nonlinear regression to 50 tide gauges that determines the spatially varying controls on daily mean water level for water years 2004–2022. Results show that elevated river flow and pumping (99th percentile) raise water level up to 6 m and lower it up to 0.35 m, respectively, and …


Shallow‑Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David A. Jay, Heida Diefenderfer, Stefan Talke Nov 2023

Shallow‑Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David A. Jay, Heida Diefenderfer, Stefan Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Decreases in shallow-water habitat area (SWHA) in the Lower Columbia River and Estuary (LCRE) have adversely affected salmonid populations. We investigate the causes by hindcasting SWHA from 1928 to 2004, system-wide, based on daily higher high water (HHW) and system hypsometry. Physics-based regression models are used to represent HHW along the system as a function of river inflow, tides, and coastal processes, and hypsometry is used to estimate the associated SWHA. Scenario modeling is employed to attribute SWHA losses to levees, flow regulation, diversion, navigational development, and climate-induced hydrologic change, for subsidence scenarios of up to 2 m, and for …


Localization And Shape Determination Of A Hidden Corridor In The Great Pyramid Of Giza Using Non-Destructive Testing, Mohamed Elkarmoty, Johannes Rupfle, Khalid Helal, Mohamed Sholqamy, Mohamed Fath-Elbab, Jochen Kollofrath, Thomas Schumacher, Multiple Additional Authors Oct 2023

Localization And Shape Determination Of A Hidden Corridor In The Great Pyramid Of Giza Using Non-Destructive Testing, Mohamed Elkarmoty, Johannes Rupfle, Khalid Helal, Mohamed Sholqamy, Mohamed Fath-Elbab, Jochen Kollofrath, Thomas Schumacher, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

Built over 4500 years ago, the Great Pyramid of Giza, Egypt, is the only remaining structure of the Wonders of the Ancient World as described by the ancient Greek historian Herodotus. Despite this long existence, only recently has modern science and technology been employed to study this massive stone structure. Cosmic-ray muon radiography throughout the ScanPyramids project has detected a large void above the Grand Gallery of the Great Pyramid and a smaller unidentified void behind the so-called Chevron. The Chevron is an assembly of four large limestone blocks arranged in the shape of two inverted downward open angles. Guided …


Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel, Alistair Leverett, Anne Borland, Emma Inge, Samantha Hartzell Aug 2023

Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel, Alistair Leverett, Anne Borland, Emma Inge, Samantha Hartzell

Civil and Environmental Engineering Faculty Publications and Presentations

Crassulacean Acid Metabolism (CAM) is a photosynthetic adaptation found in at least 38 plant families. Typically, the anatomy of CAM plants is characterised by large photosynthetic cells and a low percentage of leaf volume comprised of internal air space (% IAS). It has been suggested that reduced mesophyll conductance (gm) arising from low % IAS benefits CAM plants by preventing the movement of CO2 out of cells and ultimately minimising leakage of CO2 from leaves into the atmosphere during day-time decarboxylation. Here, we propose that low % IAS does not provide any adaptive benefit to …


Modeling Cyanotoxin Production, Fate, And Transport In Surface Water Bodies Using Ce-Qual-W2, Bernadel Rose Hintz Garstecki, Scott A. Wells Jul 2023

Modeling Cyanotoxin Production, Fate, And Transport In Surface Water Bodies Using Ce-Qual-W2, Bernadel Rose Hintz Garstecki, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Cyanobacteria are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change are expected to increase the occurrence of cyanobacteria, and it is vital that we protect our drinking water supplies and natural water resources. Modeling the production, fate, and transport of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. The research provided here offers an overview of some of the main cyanotoxins of concern and presents preliminary models for the transport and …


Data From: Shallow-Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David Jay, Heida Diefenderfer, S. A. Talke Jun 2023

Data From: Shallow-Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David Jay, Heida Diefenderfer, S. A. Talke

Civil and Environmental Engineering Faculty Datasets

This is the dataset to accompany the article, Shallow-Water Habitat in the Lower Columbia River Estuary: A Highly Altered System [Data set], accepted for publication in Estuaries and Coasts.

OVERVIEW OF THE SUPPLEMENTAL DATA FILES:

The files include water level data for 26 locations across varying time frames, as described below, and Columbia and Willamette River discharge measurements and estimates for observed, naturalized, and adjusted flows.

All water levels:

1. All water levels are reported as six-minute interpolated water level records derived from measured water levels. 2. The first column is date-time with date and time separated by a …


Impacts Of A Cascadia Subduction Zone Earthquake On Water Levels And Wetlands Of The Lower Columbia River And Estuary, M. W. Brand, Heida Diefenderfer, J. E. O’Connor, Amy B. Borde, D. A. Jay, Aqeel Al-Bahadily, M. Mckeon, S. A. Talke Jun 2023

Impacts Of A Cascadia Subduction Zone Earthquake On Water Levels And Wetlands Of The Lower Columbia River And Estuary, M. W. Brand, Heida Diefenderfer, J. E. O’Connor, Amy B. Borde, D. A. Jay, Aqeel Al-Bahadily, M. Mckeon, S. A. Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Subsidence after a subduction zone earthquake can cause major changes in estuarine bathymetry. Here, we quantify the impacts of earthquake-induced subsidence on hydrodynamics and habitat distributions in a major system, the lower Columbia River Estuary, using a hydrodynamic and habitat model. Model results indicate that coseismic subsidence increases tidal range, with the smallest changes at the coast and a maximum increase of ∼10% in a region of topographic convergence. All modeled scenarios reduce intertidal habitat by 24%–25% and shifts ∼93% of estuarine wetlands to lower-elevation habitat bands. Incorporating dynamic effects of tidal change from subsidence yields higher estimates of remaining …


Damage Tracking In Laboratory Reinforced Concrete Bridge Columns Under Reverse-Cyclic Loading Using Fusion-Based Imaging, Sina Mehdinia, A K M Golam Murtuz, Thomas Schumacher, Peter Dusicka May 2023

Damage Tracking In Laboratory Reinforced Concrete Bridge Columns Under Reverse-Cyclic Loading Using Fusion-Based Imaging, Sina Mehdinia, A K M Golam Murtuz, Thomas Schumacher, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

Fusion-based imaging using ground-penetrating radar (GPR) and ultrasonic echo array (UEA) was employed to track damage progression in the columns of two full-scale reinforced concrete (RC) bridge column-footing subassembly laboratory specimens. The specimens had different lap-splice detailing and were subjected to reverse-cyclic lateral loading simulating a subduction zone earthquake. GPR and UEA scans were performed on the east and west faces of the columns at select ductility levels. Reconstructed images were obtained using the extended total focusing method (XTFM) and fused using a wavelet-based technique. Composite images of each column's interior were created by merging the images from both sides. …


Global Water Level Variability Observed After The Hunga Tonga-Hunga Ha’Apai Volcanic Tsunami Of 2022, Adam Thomas Devlin, David A. Jay, Stefan Talke, Jiayi Pan Apr 2023

Global Water Level Variability Observed After The Hunga Tonga-Hunga Ha’Apai Volcanic Tsunami Of 2022, Adam Thomas Devlin, David A. Jay, Stefan Talke, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

The eruption of the Hunga Tonga-Hunga Ha'apai volcano on 15 January 2022 provided a rare opportunity to understand global tsunami impacts of explosive volcanism and to evaluate future hazards, including dangers from “volcanic meteotsunamis” (VMTs) induced by the atmospheric shock waves that followed the eruption. The propagation of the volcanic and marine tsunamis was analyzed using globally distributed 1 min measurements of air pressure and water level (WL) (from both tide gauges and deep-water buoys). The marine tsunami propagated primarily throughout the Pacific, reaching nearly 2 m at some locations, though most Pacific locations recorded maximums lower than 1 m. …


Data From: Warming Of The Columbia River, 1853 To 2018, Malia Hanae Scott, Stefan Talke, David Jay, Heida Diefenderfer Apr 2023

Data From: Warming Of The Columbia River, 1853 To 2018, Malia Hanae Scott, Stefan Talke, David Jay, Heida Diefenderfer

Civil and Environmental Engineering Faculty Datasets

Water temperature is a critical ecological indicator; however, few studies have statistically modeled century-scale trends in riverine or estuarine water temperature, or their cause. Here, we recover, digitize, and analyze archival temperature measurements from the 1850s onward to investigate how and why water temperatures in the lower Columbia River are changing. To infill data gaps and explore changes, we develop regression models of daily historical Columbia River water temperature using time-lagged river flow and air temperature as the independent variables. Models were developed for 3 time periods (mid-19 th , mid-20 th , and early 21 st century), using archival …


Warming Of The Columbia River, 1853 To 2018, Malia Hanae Scott, Stefan Talke, David Jay, Heida Diefenderfer Apr 2023

Warming Of The Columbia River, 1853 To 2018, Malia Hanae Scott, Stefan Talke, David Jay, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Water temperature is a critical ecological indicator; however, few studies have statistically modeled century-scale trends in riverine or estuarine water temperature, or their cause. Here, we recover, digitize, and analyze archival temperature measurements from the 1850s onward to investigate how and why water temperatures in the lower Columbia River are changing. To infill data gaps and explore changes, we develop regression models of daily historical Columbia River water temperature using time-lagged river flow and air temperature as the independent variables. Models were developed for 3 time periods (mid-19 th , mid-20 th , and early 21 st century), using archival …


Numerical Modeling Of A Pile-Supported Wharf Subjected To Liquefaction-Induced Lateral Ground Deformations, Milad Souri, Arash Khosravifar, Stephen Dickenson, Nason Mccullough, Scott Schlechter Feb 2023

Numerical Modeling Of A Pile-Supported Wharf Subjected To Liquefaction-Induced Lateral Ground Deformations, Milad Souri, Arash Khosravifar, Stephen Dickenson, Nason Mccullough, Scott Schlechter

Civil and Environmental Engineering Faculty Publications and Presentations

Fully-coupled nonlinear dynamic analysis is increasingly used for assessing the seismic performance of pile-supported wharf structures subjected to liquefaction-induced lateral ground deformations. Several numerical challenges exist for analysis of this highly nonlinear soil-structure interaction, which require robust, yet practical, solutions that are validated with experimental data. This study presents a numerical model of a pile-supported wharf and evaluates the applicability of a soil constitutive model, and modeling assumptions and methods by using recorded data from a well-instrumented, large-scale centrifuge test. The objectives of this study include: (a) evaluating the performance of a recently developed pressure-dependent multi-yield surface constitutive soil model …


Driver And Bicyclist Comprehension Of Blue Light Detection Confirmation Systems, Douglas P. Cobb, Hisham Jashami, Christopher Monsere, Sirisha Kothuri, David S. Hurwitz Jan 2023

Driver And Bicyclist Comprehension Of Blue Light Detection Confirmation Systems, Douglas P. Cobb, Hisham Jashami, Christopher Monsere, Sirisha Kothuri, David S. Hurwitz

Civil and Environmental Engineering Faculty Publications and Presentations

This study analyzed motorist and bicyclist understanding and preference of positive confirmation of detection of a bicycle by the traffic signal infrastructure using a blue light detection confirmation (BLDC). The research analyzed results of an online survey of 1,123 respondents and intercept survey of 337 respondents. The study initially found that participants of the survey did not understand the meaning of the blue light itself, but comprehension of the system rose from 40% to 50% when supplemental signs were used. Respondents overwhelmingly indicated that they preferred the sign option that included symbols, text, and a representation of the blue light, …


Dissecting Succulence: Crassulacean Acid Metabolism And Hydraulic Capacitance Are Independent Adaptations In Clusia Leaves, Alistair Leverett, Samantha Hartzell, Klaus Winter, Milton Garcia, Multiple Additional Authors Jan 2023

Dissecting Succulence: Crassulacean Acid Metabolism And Hydraulic Capacitance Are Independent Adaptations In Clusia Leaves, Alistair Leverett, Samantha Hartzell, Klaus Winter, Milton Garcia, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

Succulence is found across the world as an adaptation to water-limited niches. The fleshy organs of succulent plants develop via enlarged photosynthetic chlorenchyma and/or achlorophyllous water storage hydrenchyma cells. The precise mechanism by which anatomical traits contribute to drought tolerance is unclear, as the effect of succulence is multifaceted. Large cells are believed to provide space for nocturnal storage of malic acid fixed by crassulacean acid metabolism (CAM), whilst also buffering water potentials by elevating hydraulic capacitance (CFT). The effect of CAM and elevated CFT on growth and water conservation have not been compared, despite the assumption that these adaptations …


Damage Detection In Reinforced Concrete Member Using Local Time-Frequency Transform Applied To Vibration Measurements, Ning Liu, Thomas Schumacher, Yan Li, Lina Xu, Bo Wang Jan 2023

Damage Detection In Reinforced Concrete Member Using Local Time-Frequency Transform Applied To Vibration Measurements, Ning Liu, Thomas Schumacher, Yan Li, Lina Xu, Bo Wang

Civil and Environmental Engineering Faculty Publications and Presentations

Signal processing and analysis of structural vibration measurements are key components of structural damage detection (SDD) in structural health monitoring (SHM). The goal of signal processing is to extract subtle changes in the measured signals, which can be used to infer changes in structural parameters and damage. Time-frequency analysis is one of the most popular characterization methods for studying non-stationary vibration signals. In this article, the local time-frequency transform (LTFT) is applied and evaluated to calculate the time-domain signals because of its excellent time-frequency energy distribution properties. The LTFT matches the input data by the Fourier basis in an inverse …


Eugenol, Menthol And Other Flavour Chemicals In Kreteks And ‘White’ Cigarettes Purchased In Indonesia, Joanna Cohen, Beladenta Amalia, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow Jan 2023

Eugenol, Menthol And Other Flavour Chemicals In Kreteks And ‘White’ Cigarettes Purchased In Indonesia, Joanna Cohen, Beladenta Amalia, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow

Civil and Environmental Engineering Faculty Publications and Presentations

Background Flavoured tobacco products are not restricted in Indonesia, a country with about 68 million adults who smoke. Most use clove-mixed tobacco cigarettes (‘kreteks’); non-clove (‘white’) cigarettes are also available. Although the use of flavour chemicals has been identified by WHO as promoting tobacco use, little has been reported for Indonesia about the levels of flavourants in either kreteks or ‘white cigarettes’.

Methods 22 kretek brand variants and nine ‘white’ cigarette brand variants were purchased in Indonesia during 2021/2022; one of the kretek packs contained three colour-coded variants, giving a total sample number of 24 for the kreteks. Chemical analyses …


Exploratory Analysis Of Factors Affecting Home Delivery Returns, Michael Bronson, Miguel Figliozzi, Ali Riahi Samani, Sabya Mishra Jan 2023

Exploratory Analysis Of Factors Affecting Home Delivery Returns, Michael Bronson, Miguel Figliozzi, Ali Riahi Samani, Sabya Mishra

Civil and Environmental Engineering Faculty Publications and Presentations

E-commerce and house deliveries have experienced a rapid growth in the last two decades. The return of online shopping products is an undesirable side effect of online shopping that has not been properly studied in the transportation literature. Utilizing binary logit models, this research answers two novel research questions focusing on the online shopping channel: (i) What household characteristics are associated with a higher or lower propensity to return online purchases? and (ii) What type of products contribute to positive return delivery rates? To answer these questions models are developed using data collected from a household online survey of e-commerce …