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Civil and Environmental Engineering Commons™
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- Hydrologic models (30)
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- Streamflow -- Forecasting (10)
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- Oceanography -- Columbia River Estuary (Or. and Wash.) -- Mathematical models (5)
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Articles 31 - 60 of 424
Full-Text Articles in Civil and Environmental Engineering
Integrating The Interconnections Between Groundwater And Land Surface Processes Through The Coupled Nasa Land Information System And Parflow Environment, Fadji Z. Maina, Dan Rosen, Peyman Abbaszadeh, Chen Yang, Sujay V. Kumar, Matthew Rodell, Reed Maxwell
Integrating The Interconnections Between Groundwater And Land Surface Processes Through The Coupled Nasa Land Information System And Parflow Environment, Fadji Z. Maina, Dan Rosen, Peyman Abbaszadeh, Chen Yang, Sujay V. Kumar, Matthew Rodell, Reed Maxwell
Civil and Environmental Engineering Faculty Publications and Presentations
Understanding the interactions between the atmosphere, the land, and the subsurface is fundamental to hydrology and is critical for a better assessment of the impacts of climate change and human management on hydrological systems. However, many land surface models simplify the subsurface hydrology and thereby these interactions. In this study, we couple the land surface model Noah‐MP included in the NASA Land Information System (LIS) with the integrated hydrologic model ParFlow (ParFlow‐LIS) using the Earth System Modeling Framework (ESMF) and the National United Operational Prediction Capability (NUOPC). This coupling improves the simulation of water and energy cycle processes by adding …
How Was Your Crossing Experience? Development Of A Pedestrian Satisfaction With Unsignalized Crossings Scale, Seth Lajeunesse, Wesley Kumfer, Sirisha Kothuri, Krista Nordback, Nathan Mcneil
How Was Your Crossing Experience? Development Of A Pedestrian Satisfaction With Unsignalized Crossings Scale, Seth Lajeunesse, Wesley Kumfer, Sirisha Kothuri, Krista Nordback, Nathan Mcneil
Civil and Environmental Engineering Faculty Publications and Presentations
Unsignalized pedestrian crossing accommodations can improve pedestrian safety, yet their quality of service for pedestrians remains understudied. The present study explored whether and how pedestrians’ satisfaction with crossing unsignalized crossings varied according to the type of crossing accommodation used, that is, the rectangular rapid-flashing beacon (RRFB) with median island, median island alone, marked crosswalk, and unmarked crosswalk. The research team collected intercept survey and video observation data from 358 pedestrians across a total of 40 sites in two different cities. Structural equation models illustrated how pedestrians’ crossing-oriented satisfaction was shaped by their positive perceptions of safety and low levels of …
Risk-Based Methodology For Structural Evaluation Of Bridge-Sized Culverts, David Yang, Kevin White, Timothy Wood
Risk-Based Methodology For Structural Evaluation Of Bridge-Sized Culverts, David Yang, Kevin White, Timothy Wood
Civil and Environmental Engineering Faculty Publications and Presentations
This report presents the results of the project sponsored by the Federal Highway Administration (FHWA), “Risk Based Methodology for Structural Evaluation of Bridge-Sized Culverts”. The goal of this project was to develop general methodology to (a) quantify uncertainty, especially live load uncertainty, unique to bridge-sized RC box culverts and (b) analyze and calibrate reliability of culverts rated under different rating loads. Over 344 combinations of culvert designs and backfill depths were analyzed based on the AASHTO Manual for Bridge Evaluation as well as the three-dimensional finite element models (FEMs) of the soil-culvert systems. For each combination, a wide range of …
Identification And Analysis On Surface Deformation In The Urban Area Of Nanchang Based On Ps-Insar Method, Mengping Zhang, Jiayi Pan, Peifeng Ma, Hui Lin
Identification And Analysis On Surface Deformation In The Urban Area Of Nanchang Based On Ps-Insar Method, Mengping Zhang, Jiayi Pan, Peifeng Ma, Hui Lin
Civil and Environmental Engineering Faculty Publications and Presentations
Interferometric Synthetic Aperture Radar (InSAR) technology has emerged as a vital tool for monitoring surface deformation due to its high accuracy and spatial resolution. With the rapid economic development of Nanchang, extensive infrastructure development and construction activities have significantly altered the urban landscape. Underground excavation and groundwater extraction in the region are potential contributors to surface deformation. This study utilized Sentinel-1 satellite data, acquired between September 2018 and May 2023, and applied the Permanent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) technique to monitor surface deformation in Nanchang’s urban area. The findings revealed that surface deformation rates in the study area …
Identifying Opportunities For Nature-Based Solutions With Geospatialized Life Cycle Assessments And Fine-Scale Socioecological Data, Gabriela Shirkey, Annick Anctil, Ranjeet John, Venkatesh Kolluru, Leah Mungai, Herve Kashongwe, Lauren T. Cooper, Ilke Celik, Joshua B. Fisher, Jiquan Chen
Identifying Opportunities For Nature-Based Solutions With Geospatialized Life Cycle Assessments And Fine-Scale Socioecological Data, Gabriela Shirkey, Annick Anctil, Ranjeet John, Venkatesh Kolluru, Leah Mungai, Herve Kashongwe, Lauren T. Cooper, Ilke Celik, Joshua B. Fisher, Jiquan Chen
Civil and Environmental Engineering Faculty Publications and Presentations
As we increasingly understand the impact that land management intensification has on local and global climate, the call for nature-based solutions (NbS) in agroecosystems has expanded. Moreover, the pressing need to determine when and where NbS should be used raises challenges to socioecological data integration as we overcome spatiotemporal resolutions. Natural and working lands is an effort promoting NbS, particularly emissions reduction and carbon stock maintenance in forests. To overcome the spatiotemporal limitation, we integrated life cycle assessments (LCA), an ecological carbon stock model, and a land cover land use change model to synthesize rates of global warming potential (GWP) …
A Novel Maximum Likelihood Based Probabilistic Behavioral Data Fusion Algorithm For Modeling Residential Energy Consumption, Tanmoy Bhowmik, Naveen Chandra Iraganaboina, Naveen Eluru
A Novel Maximum Likelihood Based Probabilistic Behavioral Data Fusion Algorithm For Modeling Residential Energy Consumption, Tanmoy Bhowmik, Naveen Chandra Iraganaboina, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
The current research effort is focused on improving the effective use of the multiple disparate sources of data available by proposing a novel maximum likelihood based probabilistic data fusion approach for modeling residential energy consumption. To demonstrate our data fusion algorithm, we consider energy usage by fuel type variables (for electricity and natural gas) in residential dwellings as our dependent variable of interest, drawn from residential energy consumption survey (RECS) data. The national household travel survey (NHTS) dataset was considered to incorporate additional variables that are not available in the RECS data. With a focus on improving the model for …
Editorial: Advances In Ecological Environment Changes In Coastal And Estuarine Waters In Response To Hydrodynamic Variability, Jiayi Pan, Yeqiang Shu, Zhe-Wen Zheng, Adam T. Devlin, Majid Nazeer, Andrew M. Fischer
Editorial: Advances In Ecological Environment Changes In Coastal And Estuarine Waters In Response To Hydrodynamic Variability, Jiayi Pan, Yeqiang Shu, Zhe-Wen Zheng, Adam T. Devlin, Majid Nazeer, Andrew M. Fischer
Civil and Environmental Engineering Faculty Publications and Presentations
Over the past few decades, coastal and estuarine ecological environments have undergone significant and rapid transformations, driven by a range of factors, with the variability in hydrodynamic conditions being one of the most prominent (Elliott et al., 2019; Statham, 2012; Da et al., 2024). These dynamic forces influence water movement, sediment transport, and nutrient cycling, all of which are critical components affecting the health and stability of these ecosystems (van Vliet et al., 2023; Li et al., 2023). Consequently, understanding and interpreting hydrodynamic processes in coastal and estuarine waters are fundamental to unraveling the mechanisms behind ecological changes. This task …
Exploring The Relationship Between Covid-19 Transmission And Population Mobility Over Time, Tanmoy Bhowmik, Naveen Eluru
Exploring The Relationship Between Covid-19 Transmission And Population Mobility Over Time, Tanmoy Bhowmik, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
This study explores the dynamic relationship between COVID-19 transmission and transportation mobility, with an emphasis on understanding the time-varying bidirectional interplay across the different phases of the pandemic. To gain insight into this relationship, we analyzed county-level data on transmission and mobility patterns from the United States over a 74-week period using a comprehensive list of factors including: temporal factors, socio-demographics, health indicators, health care infrastructure attributes, and spatial factors. For our analysis, we proposed a simultaneous econometric model system that explicitly accounts for the bidirectional relationship between COVID-19 transmission and mobility patterns while also accounting for the influence of …
A Systematic Unified Approach For Addressing Temporal Instability In Road Safety Analysis, Kazi Redwan Shabab, Tanmoy Bhowmik, Mohamed H. Zaki, Naveen Eluru
A Systematic Unified Approach For Addressing Temporal Instability In Road Safety Analysis, Kazi Redwan Shabab, Tanmoy Bhowmik, Mohamed H. Zaki, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
Multivariate models are widely employed for crash frequency analysis in traffic safety literature. In the context of analyzing data for multiple instances (such as years), it becomes essential to evaluate the stability of parameters over time. The current research proposes a novel approach, labelled the mixed spline indicator pooled model, that offers significant enhancement relative to current approaches employed for capturing temporal instability. The proposed approach entails carefully creating independent variables that allow us to measure parameter slope changes over time and can be easily integrated into existing methodological frameworks. The current research effort compares four multivariate model systems: year …
Comparing The Performance Of Different Missing Data Imputation Approaches In Discrete Outcome Modeling, Md Istiak Jahan, Tanmoy Bhowmik, Lauren Hoover, Naveen Eluru
Comparing The Performance Of Different Missing Data Imputation Approaches In Discrete Outcome Modeling, Md Istiak Jahan, Tanmoy Bhowmik, Lauren Hoover, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
Although several approaches exist for data imputation, these approaches are not commonly applied in transportation. The current paper is geared toward assisting transportation researchers and practitioners in developing models using datasets with missing data. The study begins with a data simulation exercise evaluating different solutions implemented for missing data. The dimensions considered in our analysis include: the nature of independent variables, different types of missing variables, different shares of missing values, multiple data sample sizes, and evaluation of single imputation (SI), multiple imputation (MI) and complete case data (CCD) approach. The comparison is conducted by adopting the appropriate inference process …
Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy
Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy
Civil and Environmental Engineering Faculty Publications and Presentations
Evacuation behavior models estimated using post-disaster surveys are not adequate to predict real-time dynamic population response as a hurricane unfolds. With the emergence of ubiquitous technology and devices in recent times, social media data with its higher spatio-temporal coverage has become a potential alternative for understanding evacuation behaviour during hurricanes. However, these data are often associated with selection bias and population representativeness issues. To that extent, the current study proposes a novel data fusion algorithm to combine heterogeneous data sources from transportation systems and social media, in a unified framework to understand and predict real-time population response during hurricanes. Specifically, …
Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot
Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot
Civil and Environmental Engineering Faculty Publications and Presentations
Our purpose was to test the hypothesis that ultrasonic cigarettes (u-cigarettes), which operate at relatively low temperatures, produce aerosols that are less harmful than heated-coil pod-style electronic cigarettes (e-cigarettes). The major chemicals in SURGE u-cigarette fluids and aerosols were quantified, their cytotoxicity and cellular effects were assessed, and a Margin of Exposure risk assessment was performed on chemicals in SURGE fluids. Four SURGE u-cigarette flavor variants ("Blueberry Ice," "Watermelon Ice," "Green Mint," and "Polar Mint") were evaluated. Flavor chemicals were quantified in fluids and aerosols using gas chromatography/mass spectrometry. Cytotoxicity and cell dynamics were assessed using the MTT assay, live-cell …
Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru
Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
Using data from a developing country, the current study develops a copula-based joint modeling framework to study crash type and driver injury severity as two dimensions of the severity process. To be specific, a copula-based multinomial logit model (for crash type) and generalized ordered logit model (for driver severity) is estimated in the study. The data for our analysis is drawn from Bangladesh for the years of 2000 to 2015. Given the presence of multiple years of data, we develop a novel spline variable generation approach that facilitates easy testing of variation in parameters across time in crash type and …
Framework And Methodology For Risk-Based Bridge And Tunnel Asset Management: Objective Risk Assessment And Network Level Evaluation, David Y. Yang, Arash Khosravifar, Diane Moug, Avinash Unnikrishnan
Framework And Methodology For Risk-Based Bridge And Tunnel Asset Management: Objective Risk Assessment And Network Level Evaluation, David Y. Yang, Arash Khosravifar, Diane Moug, Avinash Unnikrishnan
Civil and Environmental Engineering Faculty Publications and Presentations
This report presents the results of the project on establishing a general framework and methodology for risk-based bridge and tunnel asset management. The research was carried out at Portland State University in collaboration with engineers and officials at Oregon Department of Transportation (ODOT) and Federal Highway Administration (FHWA). The primary goal of the research is to achieve risk-based transportation asset management based on (a) objective and consistent risk assessment and (b) effective prioritization and optimization of intervention strategies. Volume I of this report presents methods and findings in the base phase (Phase I) of the project, which is focused on …
Early Detection Of Structural Damage In Uhpfrc Structures Through The Combination Of Acoustic Emission And Ultrasonic Stress Wave Monitoring, Numa Bertola, Thomas Schumacher, Ernst Niederleithinger, Eugen Brühwiler
Early Detection Of Structural Damage In Uhpfrc Structures Through The Combination Of Acoustic Emission And Ultrasonic Stress Wave Monitoring, Numa Bertola, Thomas Schumacher, Ernst Niederleithinger, Eugen Brühwiler
Civil and Environmental Engineering Faculty Publications and Presentations
Ultra-High-Performance Fiber-Reinforced Cementitious Composite (UHPFRC) offers several advantages compared to concrete, notably due to the strain hardening behavior under tensile actions. Structures made of this composite material are lightweight and highly durable, thanks to the UHPFRC waterproofing quality. Nonetheless, the tensile behavior leads to a different cracking pattern than conventional concrete and is not fully understood yet. This paper presents a combined approach using both passive ultrasonic (US) stress wave (or acoustic emission) and active US stress wave monitoring to localize and quantify damage progression in a full-scale UHPFRC beam during experimental load testing. The proposed monitoring approach involves 24 …
Advanced Acoustic Emission-Based Shm For Concrete Structures: Real-Time, High-Precision Imaging Of Crack Geometry And Damage Sourcetype Using Moment Tensor Inversion, Seyyedmaalek Momeni, Thomas Schumacher, Lindsay Linzer, Brice Lecampion
Advanced Acoustic Emission-Based Shm For Concrete Structures: Real-Time, High-Precision Imaging Of Crack Geometry And Damage Sourcetype Using Moment Tensor Inversion, Seyyedmaalek Momeni, Thomas Schumacher, Lindsay Linzer, Brice Lecampion
Civil and Environmental Engineering Faculty Publications and Presentations
In this paper, we introduce a novel automated and high-precision acoustic emission (AE) monitoring algorithm and the software SIMORGH, which is suitable for structural health monitoring (SHM) of civil structures. Initially developed for laboratory-scale hydraulic fracture monitoring, this core software has been effectively scaled up to meter-level applications and is compatible with heterogeneous media such as concrete. It is designed to work with various standard data formats and is handles both trigger-based and continuous data. We present initial results from implementing this software in the AE monitoring of two 4.88-meter-long concrete beams in a laboratory setting, comparing it with manually …
Combined Passive And Active Ultrasonic Stress Wave Monitoring Of Concrete Structures: An Overview Of Data Analysis Techniques And Their Applications And Limitations, Thomas Schumacher, Numa Bertola, Niklas Epple, Eugen Bruehwiler, Ernst Niederleithinger
Combined Passive And Active Ultrasonic Stress Wave Monitoring Of Concrete Structures: An Overview Of Data Analysis Techniques And Their Applications And Limitations, Thomas Schumacher, Numa Bertola, Niklas Epple, Eugen Bruehwiler, Ernst Niederleithinger
Civil and Environmental Engineering Faculty Publications and Presentations
Combined passive ultrasonic (US) stress wave [better known as acoustic emission (AE)] and active US stress wave monitoring has been shown to provide a more holistic picture of ongoing fracture processes, damage progression, as well as slowly occurring aging and degradation mechanisms in concrete structures. Traditionally, different data analysis techniques have been used to analyze the data generated from these two monitoring techniques. For passive US stress wave monitoring, waveform amplitudes, hit rates, source localization, and b-value analysis, among others, have been used to detect and locate cracking. On the other hand, amplitude tracking, magnitude squared coherence (MSC), and coda …
Processes For Depositing Functionalized Nanoparticles Upon A Substrate, Erik T. Thostenson, Thomas Schumacher
Processes For Depositing Functionalized Nanoparticles Upon A Substrate, Erik T. Thostenson, Thomas Schumacher
Civil and Environmental Engineering Faculty Publications and Presentations
Processes for depositing functionalized nanoparticles upon a non-conductive substrate are disclosed herein. The processes may include the step of aerosolizing one or more particles into suspension within a gas, each of the one or more particles comprising functionalized nanoparticles having an electric charge. The processes may include the step the step of attracting the one or more particles onto a non-conductive substrate by a static electric charge opposite of the electric charge, wherein at least portions of the non-conductive substrate are having the static electric charge. The processes may include the step of depositing the functionalized nanoparticles onto the non-conductive …
Investigation Of Piezocone Dissipation Test Interpretation In Clay Accounting For Vertical And Horizontal Porewater Pressure Dissipation With A Large Deformation Axisymmetric Penetration Model, Diane Moug, Andrew Huffman, Jason T. Dejong
Investigation Of Piezocone Dissipation Test Interpretation In Clay Accounting For Vertical And Horizontal Porewater Pressure Dissipation With A Large Deformation Axisymmetric Penetration Model, Diane Moug, Andrew Huffman, Jason T. Dejong
Civil and Environmental Engineering Faculty Publications and Presentations
The piezocone (CPTu) dissipation test is used to characterize how the applied load from the penetrating cone is distributed between the soil and pore fluid during both penetrometer advancement and when penetration is paused. The coefficient of consolidation is often estimated from CPTu dissipation tests by interpreting the rate of excess porewater pressure (∆u) decay to static conditions during a pause in cone penetration. Most CPTu dissipation test interpretation methods are based on Terzaghi consolidation theory for ∆u dissipation at the cone shoulder (u2 position) or cone face (u1 position) and assume that radial ∆u dissipation dominates the …
Imaging Of Structural Timber Based On In Situ Radar And Ultrasonic Wave Measurements: A Review Of The State-Of-The-Art, Narges Pahnabi, Thomas Schumacher, Arijit Sinha
Imaging Of Structural Timber Based On In Situ Radar And Ultrasonic Wave Measurements: A Review Of The State-Of-The-Art, Narges Pahnabi, Thomas Schumacher, Arijit Sinha
Civil and Environmental Engineering Faculty Publications and Presentations
With the rapidly growing interest in using structural timber, a need exists to inspect and assess these structures using non-destructive testing (NDT). This review article summarizes NDT methods for wood inspection. After an overview of the most important NDT methods currently used, a detailed review of Ground Penetrating Radar (GPR) and Ultrasonic Testing (UST) is presented. These two techniques can be applied in situ and produce useful visual representations for quantitative assessments and damage detection. With its commercial availability and portability, GPR can help rapidly identify critical features such as moisture, voids, and metal connectors in wood structures. UST, which …
An Adaptive Large Neighborhood Search For The Multi-Vehicle Profitable Tour Problem With Flexible Compartments And Mandatory Customers, Vincent F. Yu, Nabila Yuraisyah Salsabila, Aldy Gunawan, Anggun Nurfitriani Handoko
An Adaptive Large Neighborhood Search For The Multi-Vehicle Profitable Tour Problem With Flexible Compartments And Mandatory Customers, Vincent F. Yu, Nabila Yuraisyah Salsabila, Aldy Gunawan, Anggun Nurfitriani Handoko
Civil and Environmental Engineering Faculty Publications and Presentations
The home-refill delivery system is a business model that addresses the concerns of plastic waste and its impact on the environment. It allows customers to pick up their household goods at their doorsteps and refill them into their own containers. However, the difficulty in accessing customers’ locations and product consolidations are undeniable challenges. To overcome these issues, we introduce a new variant of the Profitable Tour Problem, named the multi-vehicle profitable tour problem with flexible compartments and mandatory customers (MVPTPFC-MC). The objective is to maximize the difference between the total collected profit and the traveling cost. We model the proposed …
On The Feasibility Of Ultrasonic Full Waveform Evaluation With Changing Testing Conditions For The Quality Control Of Manufacturing Parts, Simon Schmid, Thomas Schumacher, Christian U. Grosse
On The Feasibility Of Ultrasonic Full Waveform Evaluation With Changing Testing Conditions For The Quality Control Of Manufacturing Parts, Simon Schmid, Thomas Schumacher, Christian U. Grosse
Civil and Environmental Engineering Faculty Publications and Presentations
Fast volumetric non-destructive testing methods are needed, especially for quality control in manufacturing lines. Ultrasonic testing with full waveform evaluation is a promising method for this. However, changes in coupling conditions or environmental factors can significantly alter the ultrasound signal, sometimes more than actual defects. This study investigates the effect of various factors on the ultrasound signal based on a Monte Carlo study with wavefield simulations. The test specimens comprise aluminium plates with holes of varying sizes and positions. Using both experimental as well as simulated data, the performance of two commonly used comparison metrics, namely the R2 score and …
Implementation Of A Realistic Artificial Data Generator For Crash Data Generation, Lauren Hoover, Md. Istiak Jahan, Tanmoy Bhowmik, Sudipta Dey Tirtha, Karthik C. Konduri, John Ivan, Kai Wang, Shanshan Zhao, Joshua Auld, Naveen Eluru
Implementation Of A Realistic Artificial Data Generator For Crash Data Generation, Lauren Hoover, Md. Istiak Jahan, Tanmoy Bhowmik, Sudipta Dey Tirtha, Karthik C. Konduri, John Ivan, Kai Wang, Shanshan Zhao, Joshua Auld, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
In this paper, a framework is outlined to generate realistic artificial data (RAD) as a tool for comparing different models developed for safety analysis. The primary focus of transportation safety analysis is on identifying and quantifying the influence of factors contributing to traffic crash occurrence and its consequences. The current framework of comparing model structures using only observed data has limitations. With observed data, it is not possible to know how well the models mimic the true relationship between the dependent and independent variables. Further, real datasets do not allow researchers to evaluate the model performance for different levels of …
Accommodating Spatio-Temporal Dependency In Airline Demand Modeling, Sudipta Dey Tirtha, Tanmoy Bhowmik, Naveen Eluru
Accommodating Spatio-Temporal Dependency In Airline Demand Modeling, Sudipta Dey Tirtha, Tanmoy Bhowmik, Naveen Eluru
Civil and Environmental Engineering Faculty Publications and Presentations
The objective of the current study is to examine monthly air passenger departures at the airport level considering spatial interactions between airports. In this study, we develop a novel spatial grouped generalized ordered probit (SGGOP) model system of monthly air passenger departures at the airport level. Specifically, we estimate two variants of spatial models including spatial lag model and spatial error model. In the presence of repeated demand measures for the airports, we also consider temporal variations of spatial correlation effects among proximally located airports by employing space and time-based weight matrix. The proposed model is estimated using monthly air …
Contributing Factors To Right-Turn Crash Severity At Signalized Intersections: An Application Of Econometric Modeling, Hisham Jashami, Jason C. Anderson, Hameed Mohammed, Douglas P. Cobb, David Hurwitz
Contributing Factors To Right-Turn Crash Severity At Signalized Intersections: An Application Of Econometric Modeling, Hisham Jashami, Jason C. Anderson, Hameed Mohammed, Douglas P. Cobb, David Hurwitz
Civil and Environmental Engineering Faculty Publications and Presentations
Motorists are required to interact with both roadway infrastructure and various users. The complexity of the driving task in certain scenarios can influence the frequency and severity of crashes. Turning vehicles at intersections, for example, pose a collision risk for both motorized and non-motorized road users. The primary goal of this paper is to investigate the underlying factors which contribute to right-turn crashes at signalized intersections. Five years of crash data across Oregon were collected. A random parameters binary logit model was developed to predict the likelihood of whether a crash resulted in an injury or fatality. It was found …
Nonlinear Interactions Of Sea‐Level Rise And Storm Tide Alter Extreme Coastal Water Levels: How And Why?, H. Moftakhari, D. F. Muñoz, A. Akbari Asanjan, A. Aghakouchak, Hamid Moradkhani, David A. Jay
Nonlinear Interactions Of Sea‐Level Rise And Storm Tide Alter Extreme Coastal Water Levels: How And Why?, H. Moftakhari, D. F. Muñoz, A. Akbari Asanjan, A. Aghakouchak, Hamid Moradkhani, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
Sea-level rise (SLR) increasingly threatens coastal communities around the world. However, not all coastal communities are equally threatened, and realistic estimation of hazard is difficult. Understanding SLR impacts on extreme sea level is challenging due to interactions between multiple tidal and non-tidal flood drivers. We here use global hourly tidal data to show how and why tides and surges interact with mean sea level (MSL) fluctuations. At most locations around the world, the amplitude of at least one tidal constituent and/or amplitude of non-tidal residual have changed in response to MSL variation over the past few decades. In 37% of …
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
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
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
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
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 …