A Deep Learning Approach For Real-Time Crash Risk Prediction At Urban Arterials,
2020
University of Central Florida
A Deep Learning Approach For Real-Time Crash Risk Prediction At Urban Arterials, Pei Li
Electronic Theses and Dissertations, 2020-2023
Real-time crash risk prediction aims to predict the crash probabilities within a short time period, it is expected to play a crucial role in the advanced traffic management system. However, most of the existing studies only focused on freeways rather than urban arterials because of the complicated traffic environment of the arterials. This thesis proposes a long short-term memory convolutional neural network (LSTM-CNN) to predict the real-time crash risk at arterials. The advantage of this model is it can benefit from both LSTM and CNN. Specifically, LSTM captures the long-term dependency of the data while CNN extracts the time-invariant features. …
Structural Performance Evaluation Of Dynamic Message Signs With Adhesive And Welded Joints,
2020
South Dakota State University
Structural Performance Evaluation Of Dynamic Message Signs With Adhesive And Welded Joints, Ibin Amatya
Electronic Theses and Dissertations
The ultimate objective of this study was to determine the structural performance of the Dynamic Message Sign (DMS) bonded with chemical adhesive in terms of ultimate strength and fatigue strength. To achieve this objective, this study first investigated the effects of various parameters, including humidity and temperature on tensile, shear, peel, and cleavage strength through small-scale tests of adhesive specimens with variation in specimen width. The tensile, shear, peel, and cleavage specimens were conditioned in a temperature-humidity controlled chamber prior to its testing. The tensile, shear, peel, and cleavage specimens with different widths were tested according to American Society for …
A Review Of The Second Level Construction Studies Syllabus In Ireland: In Response To A Changing Technological Environment Promoting Digital Construction,
2020
Technological University Dublin
A Review Of The Second Level Construction Studies Syllabus In Ireland: In Response To A Changing Technological Environment Promoting Digital Construction, Bim Tudublin, Nigel Wearen
Capstone Reports
The zeitgeist of Construction Studies ought to adopt digital construction and work practises. However, legacy is slow to change/adapt, and a lack of awareness persists. From the perspective of the continuing legacy (vocational training) of Construction Studies being linked with industry, this research explores how the subject could evolve to deliver new digital skill sets and to meet the demands of the Architecture, Engineering, and Construction (AEC) sector.A pilot study was undertaken with 24 Transition Year students. The method and content of the study was based on an existing model from the Design Engineering Construction in the UK and was …
Sustainable And Resilient Construction: Current Status And Future Challenges,
2020
University College London
Sustainable And Resilient Construction: Current Status And Future Challenges, Niamh Murtagh, Lloyd Scott, Jingli Fan
Articles
The construction industry globally is one of the most environmentally damaging of sectors. Additionally, the resources consumed and the operational energy requirements of buildings are ‘locked-in’, potentially for decades. The Intergovernmental Panel on Climate Change has recognised construction as a sector in which significant improvements can, and indeed must, be made. But the industry is often argued to be unique, in its multiplicity of stakeholders, transient organisational structures, avoidance of risk and impact on society. The current Virtual Special Issue (VSI) sought to bring together a collection of papers on progress and potential for improvement in the construction sector, in …
Liana Abundance And Diversity Increase With Rainfall Seasonality Along A Precipitation Gradient In Panama,
2020
Marquette University
Liana Abundance And Diversity Increase With Rainfall Seasonality Along A Precipitation Gradient In Panama, Anthony J. Parolari, Kassandra Paul, Aaron H. Griffing, Richard Condit, Ronaldo Perez, Salomón Aguilar, Stefan A. Schnitzer
Civil and Environmental Engineering Faculty Research and Publications
In tropical regions, rainfall gradients often explain the abundance and distribution of plant species. For example, many tree and liana species adapted to seasonal drought are more abundant and diverse in seasonally-dry forests, characterized by long periods of seasonal water deficit. Mean annual precipitation (MAP) is commonly used to explain plant distributions across climate gradients. However, the relationship between MAP and plant distribution is often weak, raising the question of whether other seasonal precipitation patterns better explain plant distributions in seasonally-dry forests. In this study, we examine the relationship between liana abundance and multiple metrics of seasonal and annual rainfall …
Corrigendum To “Heavy Metal Ion Detection On A Microspot Electrode Using An Optical Electrochemical Probe” [Electrochem. Commun. 86 (2018) 94–98],
2020
Vajra Instruments
Corrigendum To “Heavy Metal Ion Detection On A Microspot Electrode Using An Optical Electrochemical Probe” [Electrochem. Commun. 86 (2018) 94–98], Santanu Roy, Abhijeet Prasad, Rahul Tevatia, Ravi Saraf
Mid-America Transportation Center: Final Reports and Technical Briefs
The authors regret to inform an error. Ravi F. Saraf of this pub- lication discloses financial interest in Vajra Instrument as its founder and President. In accordance with its Conflict of Interest policy, the University of Nebraska-Lincoln’s Conflict of Interest in Research Committee has determined that this must be disclosed. The authors would like to apologise for any inconvenience caused.
Safety Design Management Processes To Mitigate Design Errors,
2020
Walden University
Safety Design Management Processes To Mitigate Design Errors, Hernan Guadalupe
Walden Dissertations and Doctoral Studies
Some organizations lack processes to mitigate design errors that may result in potential accidents or loss of life during building construction. Managers are concerned about preventing injuries and accidents, which may promote safer working conditions during construction. Grounded in the transformation-flow-value theory of production, the purpose of this qualitative single case study was to explore safety design management processes that managers use to mitigate errors. The participants included 7 members from 1 design firm with business operations in the United States northeastern region. Data were collected from semistructured interviews and company document reviews. Data were analyzed using Yin's 5-phase, where …
Bond Behavior Of Advanced Fiber Reinforced Composite-Concrete Joints,
2020
Missouri University of Science and Technology
Bond Behavior Of Advanced Fiber Reinforced Composite-Concrete Joints, Xingxing Zou
Doctoral Dissertations
“Externally bonding advanced composite materials to concrete structures is an effective way to improve their strength, ductility, and durability. The interfacial bond behavior is fundamental to understand the overall structural performance of concrete structures strengthened with advanced composite materials. This study includes a comprehensive investigation of the bond behavior of composite-concrete joints with different fiber reinforced composite types. First, a direct approach to determine the bond-slip relationship for fiber reinforced cementitious matrix (FRCM)-concrete joints based on fiber strain measurements was proposed. Then, an analytical solution to predict the full-range response of FRCM-concrete joints was derived by assuming a trilinear bond-slip …
Econometric Frameworks For Multivariate Models: Application To Crash Frequency Analysis,
2020
University of Central Florida
Econometric Frameworks For Multivariate Models: Application To Crash Frequency Analysis, Tanmoy Bhowmik
Electronic Theses and Dissertations, 2020-2023
Econometric crash frequency models are a major analytical tool employed for examining the critical factors influencing crash occurrence. However, there are several methodological challenges associated with existing models suggesting a continual need to develop advanced econometric framework to address these gaps. The current dissertation contributes towards addressing the methodological challenges in crash frequency analysis for analyzing multiple crash frequency variables for the same study unit by proposing advanced econometric approaches. The first part of the dissertation contributes to safety literature by conducting a comparison exercise between the two major streams of multivariate approaches - (1) simulation-based approach and (2) analytical …
The Relationship Between Roadway Homogeneity And Network Coverage For Network Screening,
2020
University of Kentucky
The Relationship Between Roadway Homogeneity And Network Coverage For Network Screening, Riana Tanzen
Theses and Dissertations--Civil Engineering
In the context of transportation safety engineering, network screening is a method of identifying and prioritizing high-risk locations for potential safety investment. Since its release, the Highway Safety Manual (HSM) has facilitated the adoption of Safety Performance Functions (SPF) to predict the number of crashes for the network screening of any facility type. The predictive model becomes more reliable when developed from crash data with homogeneous roadway segments and this homogeneity can be attained by applying specific geometric attributes to the dataset. The caveat to this method is the requirement of adjustment factors (AFs) to adjust the predicted estimate for …
Fluvial Sediment Organic Matter Degradation Identified With Elemental And Isotopic Fate During Laboratory Incubation,
2020
University of Kentucky
Fluvial Sediment Organic Matter Degradation Identified With Elemental And Isotopic Fate During Laboratory Incubation, Brenden Riddle
Theses and Dissertations--Civil Engineering
Fluvial sediment is well recognized as a critical factor in both carbon and nutrient budgets within stream systems. However, we find very few studies of reactivity and isotope enrichment for stream water from agricultural and urban streams and the class of substrate known as fluvial sediment organic matter. This study investigated the hypothesis that fluvial sediment is subject to degradation even though many previous studies have considered this class of substrate generally inert. Therefore we qualify that elemental and isotopic signatures of fluvial sediment organic matter should be considered potentially non-conservative when used in tracer studies. Methods applied to this …
Adaptive Tracking Controller For Real-Time Hybrid Simulation,
2020
University of Kentucky
Adaptive Tracking Controller For Real-Time Hybrid Simulation, Alejandro Palacio-Betancur
Theses and Dissertations--Civil Engineering
Real-time hybrid simulation (RTHS) is a versatile and cost-effective testing method for studying the performance of structures subjected to dynamic loading. RTHS decomposes a structure into partitioned physical and numerical sub-structures that are coupled together through actuation systems. The sub-structuring approach is particularly attractive for studying large-scale problems since it allows for setting up large-scale structures with thousands of degrees of freedom in numerical simulations while specific components can be studied experimentally.The actuator dynamics generate an inevitable time delay in the overall system that affects the accuracy and stability of the simulation. Therefore, developing robust tracking control methodologies are necessary …
Probabilistic Approach To Water, Sediment, And Nutrient Connectivity For Advancing Watershed Modelling,
2020
University of Kentucky
Probabilistic Approach To Water, Sediment, And Nutrient Connectivity For Advancing Watershed Modelling, David Tyler Mahoney
Theses and Dissertations--Civil Engineering
The goal of this dissertation is to represent the spatial and temporal domains of water, sediment, and nutrient flux and pathways within fluvial and watershed settings. To complete this goal, we integrate connectivity theory into watershed model structures to simulate water, sediment, and nutrient movement at the fundamental unit they occur. Fluvial-based sediment and nutrient flux is an important driver of global sediment and nutrient budgets, and the quantification of which serves as an ongoing challenge to limnologists, engineers, and watershed managers. Watershed models have been richly developed over the past century, but are currently restrained by problems related to …
A Modeling Approach To Understanding Glyphosate Transport In The Belize River Watershed,
2020
University of Kentucky
A Modeling Approach To Understanding Glyphosate Transport In The Belize River Watershed, Barbara Anmei Astmann
Theses and Dissertations--Civil Engineering
Glyphosate is the most widely used herbicide worldwide and is often transported from application areas to surface water when solubilized in runoff or sorbed to eroded sediment. There is evidence that suggests both glyphosate and its main metabolite aminomethylphosphonic acid (AMPA) may pose a risk to human health, as well as cause adverse effects in the environment. However, consistent monitoring data is still limited, especially in developing countries. Belize is a developing nation with agriculture being a major sector of its economy and is heavily reliant on glyphosate. The widespread use of glyphosate in Belize may be resulting in glyphosate …
Design And Analysis Of A Pavement Marker Detection System,
2020
University of Kentucky
Design And Analysis Of A Pavement Marker Detection System, Timothy L. Johnson Ii
Theses and Dissertations--Civil Engineering
Personal injuries and property damage due to the failure of snow-plowable pavement markers which detach from pavement surfaces has led to the development of new all-plastic pavement markers which are located entirely below the planar surface of the pavement. The new all-plastic design pushes existing solutions used to avoid striping over highway reflectors into obsolescence since current solutions operate using electromagnets to sense the metal housings of snow-plowable pavement markers. A replacement solution is currently sought by the highway maintenance industry and three different marker detection methods were developed and tested on real-world highways with both new and aging pavement …
Variance Decomposition Of Forecasted Water Budget And Sediment Processes Under Changing Climate In Fluvial And Fluviokarst Systems,
2020
University of Kentucky
Variance Decomposition Of Forecasted Water Budget And Sediment Processes Under Changing Climate In Fluvial And Fluviokarst Systems, Nabil Al Aamery
Theses and Dissertations--Civil Engineering
Variance decomposition is the partitioning of different factors affecting the variance structure of a response variable. The present research focuses on future streamflow and sediment transport processes projections as the response variables. The authors propose using numerous climate factors and hydrological modeling factors that can cause any response variable to vary from historic to future conditions in any given watershed system. The climate modeling factors include global climate model, downscaling method, emission scenario, project phase, bias correction. The hydrological modeling factor includes hydrological model parametrization, and meteorological variable inclusion in the analysis. This research uses a wide spectrum of data, …
Reliability Assessment And Optimization Of Water Distribution Systems Explicitly Considering Isolation Valve Locations,
2020
University of Kentucky
Reliability Assessment And Optimization Of Water Distribution Systems Explicitly Considering Isolation Valve Locations, Erika Hernandez Hernandez
Theses and Dissertations--Civil Engineering
Water distribution systems have changed the landscape of communities through two services: 1) providing water supply for domestic and industrial use, and 2) providing water required to fight fires. However, a substantial portion of the water infrastructure in the country, as many of other public assets built over 50 years ago, are now reaching the end of their useful life; which combined with rapid growth and changes in demographics have placed water distribution pipe networks at a state that requires revitalization. The aging infrastructure along with the growing threat of natural and man-made disruptions have led water utilities to place …
Subsurface Characterization Of Internally Eroded Soils In Karst Using The Cone Penetration Test,
2020
University of Central Florida
Subsurface Characterization Of Internally Eroded Soils In Karst Using The Cone Penetration Test, Ryan Shamet
Electronic Theses and Dissertations, 2020-2023
Sinkholes are a major geohazard with life-threatening consequences when not properly detected and mitigated. Geologic conditions comprised of soluble bedrock (e.g., limestone or other carbonate-based lithologies) overlain by fine-grained sandy and clayey soils, are known internationally as "karst topography" and is generally characterized by such sinkholes, caves, sinking streams, and highly variable groundwater flow conditions. Karst sinkholes, however, are complex geohazards and are difficult to precisely characterize through geotechnical considerations alone. Deterministic methods (e.g., analytical and numerical solutions) may provide for a more robust analysis of internal soil erosion (known as soil raveling) but have limitations for the practical use …
Methodology For Quantifying Resiliency Of Transportation Systems,
2020
Embry-Riddle Aeronautical University
Methodology For Quantifying Resiliency Of Transportation Systems, Hannah Rose Russell
Doctoral Dissertations and Master's Theses
The National Science Foundation’s definition of resiliency is “the ability to prepare and plan for, absorb, recover from, or more successfully adapt to actual or potential adverse events” (National Science Foundation, 2016). While this definition is informative and useful, it lacks a quantitative reference. There is a need for a method of quantifying resilience to better plan and prepare for system wide disruptions. The research effort described herein provides a quantifiable measures of system resiliency, consistent with NSF’s definition. Fundamentally, a system disruption can be partitioned into five distinctive states: the stable pre-event state, the absorption state, the disrupted state, …
Peak Pressures On Low Rise Buildings: Cfd With Les Versus Full Scale And Wind Tunnel Measurements,
2020
Louisiana State University
Peak Pressures On Low Rise Buildings: Cfd With Les Versus Full Scale And Wind Tunnel Measurements, Aly Mousaad Aly, Hamzeh Gol-Zaroudi
Faculty Publications
This paper focuses on the processes of wind flow in the atmospheric boundary layer, to produce realistic full-scale pressures for the design of low-rise buildings. CFD with LES turbulence closure is implemented on a scale 1:1 prototype building. A proximity study was executed computationally in CFD with LES that suggests new recommendations on the computational domain size, in front of a building model, apart from common RANS-based guidelines (e.g. COST and AIJ). Our findings suggest a location of the test building, different from existing guidelines, and the inflow boundary proximity influences pressure correlation and reproduction of peak loads. The CFD …
