Civil and Environmental Engineering Commons^™

Covid-19 And Public Transportation: Current Assessment, Prospects, And Research Needs, Alejandro Tirachini, Oded Cats

Journal of Public Transportation

The COVID-19 pandemic poses a great challenge for contemporary public transportation worldwide, resulting from an unprecedented decline in demand and revenue. In this paper, we synthesize the state-of-the-art, up to early June 2020, on key developments regarding public transportation and the COVID-19 pandemic, including the different responses adopted by governments and public transportation agencies around the world, and the research needs pertaining to critical issues that minimize contagion risk in public transportation in the so-called post-lockdown phase. While attempts at adherence to physical distancing (which challenges the very concept of mass public transportation) are looming in several countries, the latest …

Extracting Bus Transit Boarding And Alighting Information Using Smart Card Transaction Data, Zhen Chen, Wei Fan

Journal of Public Transportation

The smart card–based automated fare collection (AFC) technologies provide new opportunities for transportation data collection since smart card data (SCD) contain a significant amount of archived information that can be gathered and leveraged to help estimate public transit origin-destination (OD) matrices. Both boarding and alighting location detection are important particularly when there is no automatic vehicle location (AVL) system or other information in the database. With the analysis of raw data using limited information in this paper, an algorithm for boarding stop identification is presented after the trip direction and boarding cluster identification. Alighting stops are then identified based on …

Mobility-As-A-Service: Assessing Performance And Sustainability Effects Of An Integrated Multi-Modal Simulated Transportation Network, Mohamed El-Agroudy

Electronic Theses and Dissertations, 2020-2023

Advances in information technology services have seen profound impacts on the state of transport services in the urban traffic environment. Mobility-as-a-Service (MaaS) represents the digital consolidation of users, operators, and public-private managing entities to provide totally comprehensive, integrated trip-making services. Users now enjoy extra flexibility for trip-making with new modal alternatives such as micro-mobility (e.g Lime Bikes, Spin Scooters) and rideshare (e.g. Lyft, Uber). However, current knowledge on the performance and interactive effects of these newer alternative modes is vague if not inconsistent. As such, these effects were studied through micro-simulation analysis of a multi-modal urban corridor in Orlando, Florida. …

Evaluation Of Safety And Mobility Benefits Of Connected And Automated Vehicles By Considering V2x Technologies, Md Hasibur Rahman

Electronic Theses and Dissertations, 2020-2023

The recent development in communication technologies facilitates the deployment of connected and automated vehicles (CAV) which are expected to change the future transportation system. CAV technologies enable vehicles to communicate with other vehicles through vehicle-to-vehicle (V2V) communications and the infrastructure through Vehicle-to-infrastructure (V2I) communications. Since the real-world CAV data is not currently available as of today, simulation is the most commonly used platform to evaluate the future V2X system. Although several studies evaluated the effectiveness of CAVs in a small roadway network, there is a lack of studies analyzing the impact of CAVs at the network level by considering both …

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. …

Cationic Surfactant Analysis With Good Laboratory Practice, Lawrence K. Wang, Mu-Hao Sung Wang, Nazih K. Shammas, Valerie Renak, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

The objectives of this research are to: (a) demonstrate how to select an organic solvent (such as 1,1,1-trichloroethane) for spectrophotometric determination of cationic surfactant in water and wastewater, (b) investigate and recommend possible better organic solvents for surfactant analysis; and (c) introduce good laboratory practice for personal protection, laboratory protection and hazardous waste management. Specifically this research involves selection of alternate less toxic and greener organic solvent for use in a methyl orange method for colorimetric determination of cationic surfactants in the 0.2 to 2.0 mg/L range. The principles, steps and management of the methyl orange method include: (a) complexation …

Evaluation Of The Specific Attenuation Method For Radar-Based Quantitative Precipitation Estimation: Improvements And Practical Challenges, Bong Chul Seo, Witold F. Krajewski, Alexander Ryzhkov

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study demonstrates an implementation of the prototype quantitative precipitation R estimation algorithm using specific attenuation A for S-band polarimetric radar. The performance of R(A) algorithm is assessed, compared to the conventional algorithm using radar reflectivity Z, at multiple temporal scales. Because the factor a, defined as the net ratio of A to specific differential phase, is a key parameter of the algorithm characterized by drop size distributions (e.g., differential reflectivity Zdr dependence on Z), the estimation equations of a and a proper number of Zdr–Z samples required for a reliable a estimation are examined. Based on the dynamic estimation …

Impact Of Ambient Stable Stratification On Gravity Currents Propagating Over A Submerged Canopy, Jian Zhou, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The structure and propagation of lock-release bottom gravity currents in a linearly stratified ambient with the presence of a submerged canopy are investigated for the first time using large-eddy simulations. The canopy density (i.e. The solid volume fraction), the strength of ambient stratification and the canopy height are varied to study their respective effects on the gravity current. Both denser canopies and stronger ambient stratification tend to switch the horizontal boundary along which the current propagates from the channel bed towards the canopy top (i.e. The through-To-over flow transition). It is found that the dilution of the current density is …

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 Case Study Of Drone Delivery Reliability For Time-Sensitive Medical Supplies With Stochastic Demand And Meteorological Conditions, Travis B. Glick, Miguel Figliozzi, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

Drones are increasingly being utilized to deliver medical supplies, and the COVID-19 pandemic has accelerated this trend. Drones arrive quickly by taking more direct paths and avoiding ground-based obstructions. However, drones are not completely reliable and may also experience failures and delays. For consumer products, delivery delays are an inconvenience, but for some medical supplies, delays may be fatal. This research focuses on the drone reliability of one particular type of supply and event: automatic defibrillators for out-of-hospital cardiac arrests (OHCA). A modeling framework is developed to analyze drone delivery reliability with stochastic demands and meteorological conditions. Using probability distributions …

Tide-Storm Surge Interactions In Highly Altered Estuaries: How Channel Deepening Increases Surge Vulnerability, Ramin Familkhalili, Stefan A. Talke, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

We develop idealized analytical and numerical models to study how storm surge amplitudes vary within frictional, weakly convergent, nonreflective estuaries. Friction is treated using Chebyshev polynomials. Storm surge is represented as the sum of two sinusoidal components, and a third constituent represents the semidiurnal tide (D2). An empirical fit of storm surge shows that two sinusoidal components adequately represent storm surge above a baseline value (R2 = 0.97). We find that the spatial transformation of surge amplitudes depends on the depth of the estuary, and characteristics of the surge wave including time scale, amplitude, asymmetry, and surge‐tide relative phase. Analytical …

Data Driven Synthetic Load Modeling For Smart City Energy Management Studies, Fernando Bereta Dos Reis

Electronic Theses and Dissertations

The primary aim of this dissertation is to provide synthetic residential load models with granular level information on the customers having information about the appliances that constitute each individual residential customer through time. The synthetic load model is capable of being widely utilized by the power system research community since only publicly available data is utilized for its generation. This gives researcher’s access to how the synthetic load was made and also how accurate the model is in representing real power system regions. As the title of the dissertation suggests, the synthetic residential load models are intended for smart city …

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 …

Understandings Of "Global Responsibility’ Expressed By Civil Engineers Working In London, Shannon Chance, Inez Direito, J. Mitchell

Conference papers

This paper discusses the term ‘global responsibility’, how it emerged and why, and analysis of interview data collected from nine civil engineers working in London regarding their understandings of the term. Professional Bodies often take the lead in envisioning change, by identifying the direction their professionals should take to help address society’s evolving needs and aspirations. Often, such Bodies charge academia with addressing society’s evolving needs through research, outreach, and preparing the next generation of professionals. In the UK, leaders in civil engineering have pressed for individual and collective action to facilitate sustainable development and decrease occurrence of corruption. Nevertheless, …

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 …

Thermal Analysis And Post Construction Verification, Cormac Flood, Lloyd Scott

Articles

Purpose – The residential sector in Ireland accounted for 25 per cent of energy related CO2 emissions in 2016 through burning fossil fuels, a major contributor to climate change. In support of Ireland’s CO2 reduction targets, the existing housing stock could contribute greatly to the reduction of space-heating energy demand through retrofit. Approximately 50 per cent of Ireland’s 2m dwellings pre-date building regulations and are predominantly of cavity and solid wall construction, the performance of which has not been extensively investigated at present. Although commitment to thermal upgrade/retrofit of existing buildings may increase under future government policies, the poor characterisation …

Initial Transformation Of Photo-Viable Free Amino Acids In The Presence Of Surrogate And Standard Dissolved Organic Matter Under Sunlit Irradiation, Ryan J. Kibler

Dissertations, Master's Theses and Master's Reports

With more than half of the nation’s drinking water affected by wastewater discharge from upstream and more indirect and direct reuse of treated wastewater, human health and ecotoxicological impacts resulting from effluent organic material (EfOM) will increase. Dissolved free amino acids (DFAAs), nitrogen components of EfOM, are essential nitrogen sources for microorganisms and play important roles in global N-cycling in natural aquatic environments. Several DFAAs including histidine, methionine, and tyrosine in sunlit surface waters are susceptible to direct and indirect photochemical transformation with reactive oxygen species. In this study, we investigated the reaction kinetics and initial reaction mechanisms involved in …

Computational Fluid Dynamics Study Of The Effects Of Secondary Flows In 90-Degree Pipe Elbow Erosion, O. Ayala, G. Rivera-Hernández, C. Knight

Engineering Technology Faculty Publications

Computational fluid dynamics (CFD) of particle-laden fluid flows through a 90-degree pipe elbow at Reynolds numbers 1,000 and 10,000 were completed; for different dimensionless elbow curvature ratios of 1.0, 1.5, and 2.5; and for particles with different Stokes numbers of 0.01, 0.1, 0.5, 1.0, 5.0, and 10.0. There were two scenarios in the study. For the first, the particles felt drag from the primary (or the axial) flow as well as from the secondary fluid flows in the elbow. For the second, the secondary fluid flow in the 90-degree bend was suppressed from the particle drag, thus the particles only …

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], 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.

Applied Injected Air Into Subsurface Drip Irrigation: Plant Uptake Of Pharmaceuticals And Soil Microbial Communities, Matteo D'Alessio, Lisa M. Durso, Clinton Williams, Christopher A. Olson, Chittaranjan Ray, Ellen Paparozzi

Nebraska Water Center: Faculty Publications

The growing global food security crisis is complicated by the need for increased crop production with less arable land and limited water resources. Reuse of treated wastewater for agricultural irrigation is becoming more common, often paired with other conservation measures such as subsurface drip irrigation (SDI). Passively injecting air into SDI systems increases crop yields and overcomes root zone wetting issues. However, when used with treated irrigation water, contaminants in the water might be taken up by the crops. This paper investigates the impact of air-injected water containing caffeine, carbamazepine, and gemfibrozil on plant uptake and soil microbial communities in …

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 …

The Combined Toxic Effect Of Nanoparticles And Lead In The Presence Of Algae (Raphidocelis), Xuesong Liu

Doctoral Dissertations

"The elevated toxicity of toxic metals in the presence of nanoparticles (NPs) has raised significant concerns on the NP environmental safety. This research focuses on the impact of environmental conditions, specifically algae, on this type of toxicity. An indicator aquatic organism, Ceriodaphnia dubia (C. dubia), was used to examine the combined toxicity and toxicity mitigation from algae by monitoring its 24-h mortality. Four papers are included in this research, which focus on four aspects of the combined toxicity and the corresponding algae (Raphidocelis) impact. The first paper examines the algae impact on the combined toxicity of …

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 …

Experimental Evaluation Of A Honeycomb Structure In Open Channel Flows, Kyle David Hix

Masters Theses

“Designing and controlling open channel flows presents many challenges. One such challenge is energy dissipation. This challenge is currently addressed by several means, including the use of honeycomb structures. Energy dissipation by honeycomb structures has been studied for pressurized conduit flows; however, their ability to dissipate energy in free-surface flows remains largely unexamined. This work introduces a comprehensive experimental study designed to estimate the energy dissipation through a honeycomb structure in a free-surface flow.

This work examined the energy dissipation for a range of flows, pipe lengths, and pipe diameters in two flumes. PVC pipes ranging from 6 inches to …

3d Printing Reinforced Concrete Structures, Bryce Tyler Tafolla

Masters Theses

"This study aims to investigate a 3D printing method to directly incorporate continuous reinforcement into concrete structures. The ability to design and produce complex structures with optimized topographical configuration can be used to reduce potential material waste while maintaining the required structural strength. Furthermore, the ability to actively incorporate reinforcement into printed members substantially reduces potential labor requirements and eliminates the need to set up formwork.

The study began its initial approach with a manual extrusion process containing reinforcement to observe the necessary constraints required to achieve a printing system with this functionality. The second stage of development was designing …

A Field Study Of Bioaccessible Lead In Detroit Soils: Insight Into The Effectiveness Of Phosphate-Based Lead Sequestration, Sabrina R. Good

Wayne State University Theses

Historical and contemporary use of lead (Pb) in gasoline, paints, and industry have caused lead to be ubiquitous in the urban soil environment, disproportionately affecting low-income minority children. As soil is a major exposure pathway for children, an effective remediation technique for lead-contaminated soil is urgently needed. Common remediation techniques, such as excavation or soil capping, are expensive and environmentally destructive, especially on a city-wide residential basis. Decreasing the bioavailability of lead, or the fraction which is retained by the human body, may be a more economically and environmentally conscious option for remediating lead in urban environments.

Research has demonstrated …

Water Reclamation Using Functionalized Forward Osmosis Membrane, Fnu Joshua

Electronic Theses and Dissertations, 2020-2023

This study investigated water reclamation from an impaired-quality water using forward osmosis (FO) membrane functionalized by nano zero valent iron (nZVI) loaded polyelectrolyte multilayer films. Stormwater runoff was selected as the impaired-quality water, which served as a feed solution (FS) and a NaCl salt solution at a concentration representing reverse osmosis (RO) concentrate was used a draw solution (DS). RO concentrate is another impaired-quality water that is discharged to the environmental with little or no treatment. A commercial cellulose triacetate (CTA) FO membrane was modified using poly allylamine hydrochloride (PAH) (a polycation) and poly acrylic acid (PAA) (a polyanion) following …

Present Mechanization Of Regional Tea Processing And Grading System In Bangladesh, Md Towfiqur Rahman, Marwa Rahman, Kaswar Hamid, Sabiha Ferdous, Muhammad Rashed Al Mamun

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nowadays tea is the most popular beverage crop of Bangladesh which contributes to our national GDP. There are 166 tea gardens in the various region in Bangladesh are producing tea. Some best quality tea is exporting from our country but this amount is negligible due to improper handling and processing systems. Quality tea production from processing houses is beyond control and mostly depends on the processing method. Improper handling and insufficient technology results in lower grade tea, as well as foreign contaminates, are found in made tea. This research focused on the problems of the present of tea processing and …

Recovery Of Ethyl Lactate From Washing Solution Originating From Drill Cuttings Treatment By Adsorption Process, Theary Peng Orng

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this study was to recover the washing solutions generated from drill cuttings washing process using an adsorption technology. Ethyl lactate (EL) was selected as an extracting agent for drill cuttings washing throughout the work. Various washing parameters including liquid-to-solid (L/S) ratio, washing time, mixing speed, rinse-to-solid (R/S) ratio, and rinsing time were studied with the aid of response surface methodology. Once the optimal washing conditions were obtained, the recovery of washing solutions, i.e., spent EL and rinsed water using the commercial granular activated carbon (GAC) and kapok fiber (KF) were investigated. Finally, the adsorbent modification and validation …