Architectural Engineering Commons^™

Rapid State-Of-Health Estimation Of Batteries Using Machine Learning With Limited Eearly-Discharge Voltage Data, Mohammad Bakhtiari

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

The utilization of lithium-ion batteries has been rapidly expanding across diverse sectors, including electric transportation, stationary energy storage systems, and the built environment. Ensuring a high level of reliability in these applications is essential, as the performance and safety of such systems depend strongly on the accurate assessment of the battery’s State of Health (SOH). Conventional SOH estimation techniques—often based on complex electrochemical models or extensive laboratory testing—tend to require a large number of measurements, advanced instrumentation, and high computational cost. These factors make them impractical for large-scale deployment or real-time monitoring. This study introduces a simplified machine-learning-based approach for …

Large-Scale Experimental Study On The Impact Of Air Cleaning & Ventilation On Indoor Air Quality And Student Illness-Related Absenteeism, Daud Nosham

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This large-scale randomized experimental field study investigated the effect of portable air purifiers (PAPs) on classroom’s air quality and student’s illness related absenteeism. PAPs were installed in 317 classrooms from various school districts located in Eastern Nebraska. The classrooms were randomly assigned into four conditions: three treatment conditions (T1, T2 & T3) and one control condition (device without any filter). T1 was equipped with HEPA filters, T2 added Activated Carbon (AC) layer to HEPA, and T3 further integrated Germicidal Ultraviolet (GUV) alongside HEPA and AC filters. The measured variables were carbon dioxide (CO2), fine particles (PN2.5) and coarse particles (PNcoarse), …

Resilience Of Interdependent Transportation And Healthcare Systems: A Simulation-Driven Framework Incorporating Social Equity And Facility Optimization, S. Yasaman Ahmadi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The overarching goal of this dissertation is to develop an integrated, simulation-driven framework to assess and enhance the resilience of interdependent transportation and healthcare systems before, during, and after natural hazards. By examining how spatial disruptions, social vulnerability, operational constraints, and infrastructure interdependencies affect access to and functionality of hospitals, this research offers a multifaceted evaluation of system performance under stress. This dissertation examines the impact of natural hazards, particularly floods, on the interdependent transportation and healthcare systems. The proposed approach combines and advances GIS-based network analysis, graph-theoretical modeling, and discrete-event simulation to evaluate system performance under different scenarios. The …

Modeling Degradation In Li-Ion Batteries: Analyzing Single-Cell Degradation And Applying It To Customized Pack-Level, Mohannad Y. Alkhalil

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

The rapid expansion of lithium-ion (Li-ion) battery applications in areas such as electric vehicles (EVs), renewable energy storage, and portable electronics has drawn attention to the need for improving their performance, safety, and longevity. As Li-ion batteries become essential across technologies, understanding degradation mechanisms is critical for optimizing design and ensuring reliable operation. This work provides a detailed overview of modeling degradation in Li-ion batteries, focusing on single-cell behavior and its implications for pack-level performance.

The PyBaMM (Python Battery Mathematical Modeling) package, an open-source battery simulation tool written in Python, is used for single-cell simulations. Liionpack, another Python-based library, is …

Crisis Response Hospital Physical Layout Considerations During Covid-19: A Framework For Surge Preparedness, Future Investigations, And Analysis, Golnoosh Abdolahzadeh

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This thesis investigates the intersection of hospital design and operational performance during health emergencies, explicitly focusing on layout modifications in emergency departments. The study is structured around four key components. First, it explores hospitals' significant challenges during the COVID-19 pandemic through data collected from interviews with Nebraska hospital leaders. Second, the research introduces a surge-based conceptual framework to guide hospital responses during crisis events. Developed from empirical data, the framework highlights the importance of flexible spatial planning and information-driven decision-making. Third, the study focuses on hospital physical layout considerations, identifying features that either supported or hindered Nebraska hospital operations during …

Amplification In Mems Rlc Circuits For Enhanced Sensitivity And Mems Applications, Mutaz Mohd Hamdi Al Fayad

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Micro-electro-mechanical systems (MEMS) have garnered significant attention due to their unique characteristics, including small size, high sensitivity, and cost-effective mass production. While electrostatic actuation offers low power consumption, it requires high voltage to move the MEMS structure, posing a challenge for applications such as RF switches and MEMS resonator-based sensors. Reducing the required input voltage for electrostatic MEMS remains a key research focus.

This thesis investigates voltage amplification in electrostatic MEMS through integration with resonant RLC circuits. By leveraging resonance, optimized configurations are designed to maximize voltage gain and enhance the signal-to-noise ratio. Through theoretical modeling and simulations using MATLAB …

Green Project Finance For Infrastructure And Building Construction: Instruments And Benchmarks, Yunping Liang

Durham School of Architectural Engineering and Construction: Faculty Publications

It is counterintuitive that both the practice and research on green project finance for infrastructure and building construction are ascendant and still have limited precedents, considering that individually, the two parts (i.e., project finance and sustainability in the built environment) are both familiar to the communities. To narrow the gap and facilitate the financing of the built environment’s sustainable transformation, this study systematically reviews the common instruments for financing green infrastructure and building projects. Benchmarking questions distinguishing the profile of green project finance from common construction project finance are developed based on the literature review and then are used for …

Business Model Evaluation Of Renewable Energy Community In Multi Unit Residential Building In Canada Net Metering, Considering The Regulatory Framework, Ownership And Organizational Structure, Zahra Keshavarz Moraveji, Yunping Liang, Ursula Eicker

Durham School of Architectural Engineering and Construction: Faculty Publications

Renewable Energy Community (REC) is an emerging concept that empowers local customers to generate decentralized renewable energy. Integrating RECs into the building industry presents a promising opportunity to support the transition toward net-zero cities. However, the viability of RECs depends on regional regulatory frameworks, permitted governance structures, and very importantly, business models. Compared to pioneering European countries, Canada lacks the regulatory support needed to fully enable REC. This paper proposes and evaluates various business models for potential REC implementations under Canada's existing regulatory constraints. The analyzed models focus on "behind-the-meter" electricity distribution, a multi-stakeholder type of REC, where generation occurs …

Analyzing Reciprocating Piston Expander Performance In Small-Scale Caes Considering Expansion Mismatch And Residual Mass Losses, Mehrdad Poursadegh

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Energy storage (ES) has become an essential element of modern energy systems, particularly with the rapid growth of renewable energy sources. While these sources are central to global decarbonization efforts, their intermittent nature creates significant challenges for both grid operators and end users. To address these challenges, a wide range of storage technologies have been developed ranging from large utility-scale to small behind-the-meter units. Among these, Compressed Air Energy Storage (CAES) stands out for its long lifespan, low storage cost per unit of energy, and ability to provide both electricity and thermal energy. However, small- and micro-scale CAES systems, unlike …

Association Between In Situ Ventilation And Human-Generated Aerosol Exposure In Meatpacking Plants During The Covid-19 Pandemic, Joshua L. Santarpia, Josephine Lau, Debayan Shom, Shanna A. Ratnesar-Shumate, Eric C. Carnes, Gearge W. Santarpia, Vicki L. Herrera, Danielle N. Rivera, Daniel N. Ackerman, Ashley R. Ravnholdt, John J. Lowe, Athena K. Ramos

Durham School of Architectural Engineering and Construction: Faculty Publications

During the COVID-19 pandemic, meatpacking workers were disproportionately affected by disease. Large outbreaks at meatpacking facilities resulted in loss of life and threatened the well-being of workers across the globe. Much work was done throughout the pandemic to understand and prevent these outbreaks. This study combined ventilation system evaluation and measurement of human-generated respiratory aerosol to investigate and identify areas of highest risk for disease transmission. These findings confirm that improved ventilation reduces exposure to human-generated aerosols in meatpacking facilities, including those that may contain infectious agents, such as SARS-CoV-2. This study suggests areas of greatest risk are likely areas …

Investigation Of Faults In Air-Conditioning Systems In Commercial Buildings: Occurrence, Diagnostic Validation, And Energy Impacts, Yuxuan Chen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In commercial buildings, fault detection and diagnosis (FDD) tools have been developed for detecting and diagnosing faults in building systems, which can provide useful information regarding fault locations and potential causes of faults, so that building operators and facility staff can be notified in time and quickly respond as problems arise. Nowadays, there are many commercial FDD tools available in the market, and these tools have been widely adopted in large- and medium-scale commercial buildings in the United States. Several studies have demonstrated the energy saving potential with the use of FDD in commercial HVAC systems, and one critical aspect …

Sustainable Sensing With Paper Microfluidics: Applications In Health, Environment, And Food Safety, Sanjay Kumar, Jyoti B. Kaushal, Heow Pueh Lee

Durham School of Architectural Engineering and Construction: Faculty Publications

This manuscript offers a concise overview of paper microfluidics, emphasizing its sustainable sensing applications in healthcare, environmental monitoring, and food safety. Researchers have developed innovative sensing platforms for detecting pathogens, pollutants, and contaminants by leveraging the paper’s unique properties, such as biodegradability and affordability. These portable, low-cost sensors facilitate rapid diagnostics and on-site analysis, making them invaluable tools for resource-limited settings. This review discusses the fabrication techniques, principles, and applications of paper microfluidics, showcasing its potential to address pressing challenges and enhance human health and environmental sustainability.

Modeling And Design Parameter Optimization To Improve The Sensitivity Of A Bimorph Polysilicon-Based Mems Sensor For Helium Detection, Sulaiman Mohaidat, F. M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Helium is integral in several industries, including nuclear waste management and semiconductors. Thus, developing a sensing method for detecting helium is essential to ensure the proper operation of such facilities. Several approaches can be used for helium detection, including based on the high thermal conductivity of helium, which is several times higher than air. This work utilizes the high thermal conductivity of helium to design and analyze a bimorph MEMS sensor for helium sensing applications. COMSOL Multiphysics software (version 6.2) is used to carry out this investigation. The sensor is constructed from poly-silicon and SiO₂ materials with a trenched …

Spatial Hearing In Simulated Reverberant Classroom Environments, Gabriel Seth Evan Weeldreyer

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Spatial hearing provides access to auditory spatial cues that promote speech perception in noisy listening situations. However, reverberation degrades auditory spatial cues and limits listeners’ ability to utilize these cues for segregating target speech from competing babble. Hence, spatial unmasking—an intelligibility benefit from a spatial separation between a target and masker—is reduced in reverberant environments as compared to free field. This work tests the hypothesis that interaural decorrelation, the result of increasing reverberation, will broaden the perceived auditory source width with a cascading effect of reduced auditory spatial acuity and subsequently poorer spatial unmasking. To understand the perceptual consequences of …

Seasonal Comparison Of Air Quality Variables And Evaluation Of Carbon Dioxide And Particulate Measurement Period In Classrooms, Daud Nosham

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Indoor air quality and thermal environmental variables were measured in 55 classrooms in the mid-western United States spanning a full academic year. The studied air quality and environmental factors included carbon dioxide, temperature, relative humidity, particle counts, air velocity, formaldehyde, total volatile organic compounds, carbon monoxide, nitrogen dioxide, and ozone.

Carbon dioxide and Particulate matter concentrations were measured for a four-day measurement period. Then one-day, two-day, and four-day occupied time average concentrations were calculated which were then compared statistically to figure out an appropriate measurement period for these air quality variables. Kruskal Wallis test and Wilcoxon test were used to …

Distribution Fitting And Anova Test To Analyze Pavement Sensing Patterns For Condition Assessments, Dada Zhang, Chun-Hsing Ho

Durham School of Architectural Engineering and Construction: Faculty Publications

Purpose – The purpose of this paper is to investigate the vehicle-based sensor effect and pavement temperature on road condition assessment, as well as to compute a threshold value for the classification of pavement conditions.

Design/methodology/approach – Four sensors were placed on the vehicle’s control arms and one inside the vehicle to collect vibration acceleration data for analysis. The Analysis of Variance (ANOVA) tests were performed to diagnose the effect of the vehicle-based sensors’ placement in the field. To classify road conditions and identify pavement distress (point of interest), the probability distribution was applied based on the magnitude values of …

Evolvement Of Excusable Delay Clauses In Government Contracts Since The Covid-19 Pandemic, Jung Hyun Lee, Yunping Liang, Seyed Mohammad Ehsan Tabatabaee, Bryce Riccitelli

Durham School of Architectural Engineering and Construction: Faculty Publications

Excusable delay clauses in government construction contracts, often considered boilerplate with minimal modifications, have increased in attention since the outbreak of COVID-19. Despite the studies enumerating triggering events of the clause in the background of the pandemic, it is necessary to capture insights into how the unprecedented event is systematically accommodated by contract languages. The overarching goal of this study is to identify changes in contract languages over the pre-and post-pandemic eras by state departments of transportation (DOTs), focusing on excusable delay clauses. This study conducts a content analysis and a comparative analysis of state DOT construction contract documents, including …

Opportunities And Challenges Of Generative Ai In Construction Industry: Focusing On Adoption Of Text-Based Models, Prashnna Ghimire, Kyungki Kim, Manoj Acharya

Durham School of Architectural Engineering and Construction: Faculty Publications

In the last decade, despite rapid advancements in artificial intelligence (AI) transforming many industry practices, construction largely lags in adoption. Recently, the emergence and rapid adoption of advanced large language models (LLMs) like OpenAI’s GPT, Google’s PaLM, and Meta’s Llama have shown great potential and sparked considerable global interest. However, the current surge lacks a study investigating the opportunities and challenges of implementing Generative AI (GenAI) in the construction sector, creating a critical knowledge gap for researchers and practitioners. This underlines the necessity to explore the prospects and complexities of GenAI integration. Bridging this gap is fundamental to optimizing GenAI’s …

Diagnosis Of Disease Affecting Gait With A Body Acceleration‑Based Model Using Reflected Marker Data For Training And A Wearable Accelerometer For Implementation, Mohammad Ali Takallou, Farahnaz Fallahtafti, Mahdi Hassan, Ali Al‑Ramini, Basheer Qolomany, Iraklis I. Pipinos, Sara A. Myers, F. M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper demonstrates the value of a framework for processing data on body acceleration as a uniquely valuable tool for diagnosing diseases that affect gait early. As a case study, we used this model to identify individuals with peripheral artery disease (PAD) and distinguish them from those without PAD. The framework uses acceleration data extracted from anatomical reflective markers placed in different body locations to train the diagnostic models and a wearable accelerometer carried at the waist for validation. Reflective marker data have been used for decades in studies evaluating and monitoring human gait. They are widely available for many …

Spatial Release From Masking In Anechoic And Reverberant Environments, Drake Andrew Hintz

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Listening with both ears provides children with access to binaural and monaural cues that are helpful for understanding speech in competing babbles. Specifically, when the target and masker are spatially separated, children can gain an intelligibility benefit which is known as spatial release from masking (SRM). Recent work [Peng et al., 2021 JASA] suggested that school-age children demonstrated immature SRM using binaural cues that are distorted by reverberation. In this follow-up study, we further investigate the effect of reverberant distortion on individual auditory spatial cues, namely binaural and monaural head shadow cues. We compare SRM between adults and school-age children …

Organic Electronics In Biosensing: A Promising Frontier For Medical And Environmental Applications, Jyoti Bala Kaushal, Pratima Raut, Sanjay Kumar

Durham School of Architectural Engineering and Construction: Faculty Publications

The promising field of organic electronics has ushered in a new era of biosensing technology, thus offering a promising frontier for applications in both medical diagnostics and environmental monitoring. This review paper provides a comprehensive overview of organic electronics’ remarkable progress and potential in biosensing applications. It explores the multifaceted aspects of organic materials and devices, thereby highlighting their unique advantages, such as flexibility, biocompatibility, and low-cost fabrication. The paper delves into the diverse range of biosensors enabled by organic electronics, including electrochemical, optical, piezoelectric, and thermal sensors, thus showcasing their versatility in detecting biomolecules, pathogens, and environmental pollutants. Furthermore, …

Classifying Diseases Affecting Gait With Body Acceleration-Based Machine Learning Models, Mohammad Ali Takallou

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This Ph.D. dissertation introduces a comprehensive framework designed to harness acceleration data as a uniquely valuable tool for early disease classification, specifically focusing on gait-related diseases. In the modern healthcare landscape, timely and accurate classification of such diseases is paramount, as it can significantly impact treatment outcomes and patient quality of life.

As a compelling case study, we conducted a meticulous experiment to identify individuals afflicted with peripheral artery disease (PAD) and classify them from those without PAD. Our framework leverages acceleration data extracted from strategically placed anatomical reflective markers, including locations such as the sacrum, to train sophisticated classification …

Meta-Analysis Of Insulated Concrete Wall Panel Design Methods For Shear And Flexure Behavior, Maryam Al-Bayati

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Insulated Concrete wall panels have been designed and constructed since the early 1950s with various shear ties, dimensions, and methods; nonetheless, thermal bridging and rational design are still a concern. Many companies have recently developed plastic connectors that have gradually replaced solid concrete sections and steel connectors due to their superior thermal efficiency and strength. However, there is no generally accepted method for predicting the behavior of sandwich wall panels in structural engineering practice or codes, but many methods have been used since the early 1920. This study aims to evaluate the accuracy of current methods for predicting the flexural …

Continuous Time Recurrent Network For Human Activity Detection, Abdallah Al Zubi

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Human activity detection is crucial to personalize the control of the building environment. For example, understanding certain human activities (e.g., walking, sitting, etc.) for an occupant in a building helps provide the proper thermal comfort control. However, these applications require large-scale neural networks that are challenging to implement and train.

In this thesis, we implemented a continuous-time recurrent neural network implementation (CTRNN) network that can solve real-time human activity detection with a smaller-size network. The CTRNN uses differential equations with a time constant to describe the neuron equations. It was implemented and trained for the first time using TensorFlow. Specifically, …

Ten Questions Concerning Smart And Healthy Built Environments For Older Adults, Sanjay Kumar, Samuel H. Underwood, Julie L. Masters, Natalie A. Manley, Iason Konstantzos, Josephine Lau, Ryan Haller, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

In the past decade, the term ‘global aging’ has gained much attention among researchers, policymakers, civil societies, and governments worldwide. The continuous decline in fertility rates and increased life expectancy have resulted in an ongoing demographic transition where the share of adults aged 65 or older is increasing and outnumbering children younger than five years. In the United States and other developed countries, this rapid demographic transition is expected to continue to strain the existing health infrastructure as it becomes increasingly challenging to ensure healthy living environments for older adults. The ten questions and answers in this paper have been …

Data-Driven Framework For Predicting And Scheduling Household Charging Of Evs, Ahmad Almaghrebi

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

The increasing prevalence of EV charging poses challenges for power grid stability and quality due to high charging load demands. Without effective energy management strategies for EV charging, the simultaneous power demand from numerous EVs can strain the electric grid, impacting power quality and the wholesale electricity market. To address these challenges, this dissertation presents a comprehensive framework comprising five critical tasks: analyzing EV charging behavior, optimizing charging schedules, developing predictive models, analyzing aggregated impacts, and evaluating implications of predicted user behavior on scheduling. By examining EV charging behavior at household and public charging stations, this study aims to understand …

Framework Development For Evaluating The Impacts Of Nursing Home Acoustics On Older Adults, Brian J. Puckett

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Nursing homes are complex, multi-faceted environments which provide necessary medical supervision and housing for older adults in need of long-term care. With cognitive and sensory impairments being common adversities faced throughout the aging process, research is needed to better understand characteristics of the built environment which may contribute to difficulties for nursing home residents. Noise, in particular, has been shown to be problematic for nursing home residents in a variety of ways including disrupting sleep, associating with behavioral and psychological symptoms of dementia, and leading to increased readmission to hospitals due to verbal communication misunderstandings. As the older adult population …

Signal Classification Based On Analog Computing Using Mems Network, Mohammad Okour

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

The rising complexity of machine learning algorithms and Artificial Intelligence in many applications, such as smart building, has prompted the development of alternate computing options. Because of their compact size, low power consumption, and diverse functionality, microelectromechanical systems (MEMS) have emerged as a possible candidate. This thesis focuses on using MEMS networks as computing units to classify a simple signal classification task using neural network methodology. The study intends to show the potential of using MEMS as an analog computing unit by discussing the advantage of the bi-stability pull-in behavior and hysteresis to create an accurate classifier of these waveforms. …

Toward Low Carbon Footprint And Lightweight Masonry Alkali-Activated Material, Zina Ebrahim, Mohammad Mastali, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

The portland cement concrete industry and the masonry industry are undergoing changes in response to skilled labor shortages and concerns over climate and pollution. There may be interest from parts of the industry in lower carbon footprint and lightweight masonry products. Toward this aim, the use of hemp shiv--the woody core of the hemp plant--in alkali-activated concrete was investigated herein and shown to have a wide range of impacts on the hardened state characteristics of a material suitable for structural concrete masonry units (CMUs) in accordance with ASTM C90 requirements. Hemp shiv is well known for its use in hempcrete, …

Incentivizing Electric Vehicle Adoption Through State And Federal Policies: Reviewing Influential Policies, Joshua Sabata, Subhaditya Shom, Ahmad Almaghrebi, Anne Mccollister, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

All-electric vehicles (EVs), battery-powered EVs (BEVs), and plug-in hybrid EVs (PHEVS) are gaining market share and increasing in popularity with the buying public because the battery range (longer) and cost (lower) have reached sweet spots, the charging infrastructure is more robust, and concern with global cli­mate change is high. In 2013, only 100,000 EVs were sold in the United States, but by 2022, approximately 800,000 have been purchased. A similar growth is seen in EV sup­ply equipment (EVSE), i.e., EV charging stations, with 19,742 documented EV charging station locations in the United States in 2013 to 50,054 documented EV charging …