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2024

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Identifying And Exploring Construction Pm Evolution And Research Directions, Jeffrey S. Russell, Islam H. El-Adaway, Ramy Khalef, Fareed Salih, Gasser Ali Jan 2024

Identifying And Exploring Construction Pm Evolution And Research Directions, Jeffrey S. Russell, Islam H. El-Adaway, Ramy Khalef, Fareed Salih, Gasser Ali

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Project Management (PM) Is The Process Of Organization, Allocation, And Control Of Resources To Achieve A Specific Goal. Previously, PM Focused On Planning And Executing Projects According To Predetermined Objectives, But It Has Evolved To Include The Use Of Technology To Aid In Managing And Delivering Projects. However, No Research Has Provided A Comprehensive Analysis Of This PM Evolution. To Fill This Gap, This Data-Driven Study Conducted A Scientometric Analysis, Using PM-Related Research Papers, To Identify The PM Evolution Along The Holistic Life Cycle Of Its Knowledgebase. The Findings Of This Study Identify Four Distinct PM Phases: PM 1.0, PM …


Predicting Construction Costs Under Uncertain Market Conditions: Probabilistic Forecasting Using Autoregressive Recurrent Networks Based On Deepar, Ghiwa Assaf, Rayan H. Assaad, Islam H. El-Adaway, Mohamad Abdul Nabi Jan 2024

Predicting Construction Costs Under Uncertain Market Conditions: Probabilistic Forecasting Using Autoregressive Recurrent Networks Based On Deepar, Ghiwa Assaf, Rayan H. Assaad, Islam H. El-Adaway, Mohamad Abdul Nabi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Projects Often Experience Cost Overruns Due To Market Uncertainty And Price Escalations. Traditional Cost Estimation Methods That Rely On Point Estimation Are Incapable Of Providing Prediction Intervals As Well As Probabilistic Assessment. Thus, There Is Need For An Innovative Approach To Predict The Changes And Uncertainties In Construction Material Costs. This Paper Proposes A Novel Stochastic Model To Estimate Construction Material Costs By Applying Probabilistic Forecasting Using Autoregressive Recurrent Networks. First, Price Data Was Collected For Four Different Construction Materials. Second, Data Was Divided Into A Training Set (Pre-COVID-19) And A Testing Test (Post-COVID-19). Third, The State-Of-The-Art DeepAR Algorithm Was …


Analyzing The Impact Of Db Versus Dbb On Cost Performance In Airport Development: A Data-Driven Approach, Ramy Khalef, Islam H. El-Adaway Jan 2024

Analyzing The Impact Of Db Versus Dbb On Cost Performance In Airport Development: A Data-Driven Approach, Ramy Khalef, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Construction Of Airport Projects Can Be Complex And Costly Due To The Many Stakeholders Involved And Associated Strict Timelines. Traditional Delivery Methods, Such As Design-Bid-Build (DBB), Employed In Airport Projects Often Result In Major Cost Overruns Due To Multiple Facets. Design-Build (DB) Is A Construction Method That Combines Design And Construction Under A Single Entity, And It Has The Potential To Improve Cost Performance. None Have Evaluated DB From A Cost Perspective In The Airport Sector. This Research Fills This Gap. First, The Data Is Collected And Assessed For Validity. Second, Risk Ratings For Cost Performance Are Computed. Finally, …


Exploring The Root Factors Impacting Work Zone Accidents: A Mixed-Methods Study, Bahaa Chammout, Muaz O. Ahmed, Islam H. El-Adaway Jan 2024

Exploring The Root Factors Impacting Work Zone Accidents: A Mixed-Methods Study, Bahaa Chammout, Muaz O. Ahmed, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Work Zones Are Vital For Improving Infrastructural Utilities Yet Pose Significant Dangers For Workers And Drivers Who Are Often Unfamiliar With These Areas. Prior Research Examined Various Aspects Of Work Zone Accident Causation; However, The Interrelationships And Critical Combinations Among The Contributing Factors Have Not Been Fully Analyzed. This Study Aims To Identify The Underlying Factors Contributing To Work Zone Accidents And Evaluate The Different Combinations Among Them. To This Purpose, Accident Factors Were Derived From A Total Of 133 Research Articles Addressing Work Zone Safety. Social Network Analysis (SNA) And Clustering Were Used To Comprehensively Model The Identified Factors. …


Investigating Price Fluctuation Transmission Among Construction Materials, Mohamad Abdul Nabi, Islam H. El-Adaway, Rayan H. Assaad Jan 2024

Investigating Price Fluctuation Transmission Among Construction Materials, Mohamad Abdul Nabi, Islam H. El-Adaway, Rayan H. Assaad

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Generally, Fluctuation In One Material's Price Can Cause A Series Of Chain Reactions In The Supply Chain System, Known As Price Fluctuation Transmission, As All Materials Are Interconnected And Interrelated. None Of The Previous Studies Have Investigated Price Fluctuation Transmission Among All Construction Materials. This Paper Aims To Fill This Gap In Knowledge. The Authors Collected Producer Price Index (PPI) Data For 16 Construction Materials, Modeled The Relationship Between Each Pair Of Materials Using Vector Autoregression Technique, And Validated The Causality Using Granger Causality Test. Network Analysis Was Performed To Identify The Price Fluctuation Transmission Capacity, Susceptibility, And Intermediatory Capacity …


A Bi-Functional Air Electrode Developed From A Dual-Mof Strategy For High-Performance Zinc-Air Batteries, Yasir Arafat, Muhammad Rizwan Azhar, Yijun Zhong, Xiaomin Xu, Moses O. Tadé, Zongping Shao Jan 2024

A Bi-Functional Air Electrode Developed From A Dual-Mof Strategy For High-Performance Zinc-Air Batteries, Yasir Arafat, Muhammad Rizwan Azhar, Yijun Zhong, Xiaomin Xu, Moses O. Tadé, Zongping Shao

Research outputs 2022 to 2026

A durable, high-performing and cost-effective bi-functional catalyst toward oxygen reduction/evolution reactions (ORR/OER) is the key towards the practical application of Zn-air batteries (ZABs). Here, we report a new concept of combining pristine and carbonized MOFs for developing a bifunctional electrocatalyst for ZABs, where the pristine MOF acts as a support for the OER catalysts and the carbonized MOF acts as the ORR catalyst and enhances the electronic conductivity. By electroless NiP-plating over the surface of the Fe-containing 3D MOF (MIL-100), the catalyst shows superior activity for the OER, delivering a current density of 10 mA cm−2 at an overpotential …


Cyberbullying Text Identification: A Deep Learning And Transformer-Based Language Modeling Approach, Khalid Saifullah, Muhammad Ibrahim Khan, Suhaima Jamal, Iqbal H. Sarker Jan 2024

Cyberbullying Text Identification: A Deep Learning And Transformer-Based Language Modeling Approach, Khalid Saifullah, Muhammad Ibrahim Khan, Suhaima Jamal, Iqbal H. Sarker

Research outputs 2022 to 2026

In the contemporary digital age, social media platforms like Facebook, Twitter, and YouTube serve as vital channels for individuals to express ideas and connect with others. Despite fostering increased connectivity, these platforms have inadvertently given rise to negative behaviors, particularly cyberbullying. While extensive research has been conducted on high-resource languages such as English, there is a notable scarcity of resources for low-resource languages like Bengali, Arabic, Tamil, etc., particularly in terms of language modeling. This study addresses this gap by developing a cyberbullying text identification system called BullyFilterNeT tailored for social media texts, considering Bengali as a test case. The …


An Ai-Based Conceptual Framework To Improve Program Management Of Complex Systems, Michael D. Parrish, Steven Corns Jan 2024

An Ai-Based Conceptual Framework To Improve Program Management Of Complex Systems, Michael D. Parrish, Steven Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

With evolving technologies, changing requirements, and limited budgets, governments and industries need to consider new methodologies to help streamline program lifecycle management, from cradle to grave, to ensure projects are delivered on time, on budget, and to the expected performance standards. Traditional approaches fail to adequately address the added complexities of System of Systems programs such as integration, interoperability, and variable lifecycle of subcomponents. The objective of this study is to assess and address the research question - can a new acquisition approach be designed to address and improve program lifecycle management of complex systems? A comparison study, using the …


Navigating Innovation Within A Contractor's Business Model: A System Dynamics Approach, Mariam Elazhary, Cihan Dagli, Islam H. El-Adaway Jan 2024

Navigating Innovation Within A Contractor's Business Model: A System Dynamics Approach, Mariam Elazhary, Cihan Dagli, Islam H. El-Adaway

Engineering Management and Systems Engineering Faculty Research & Creative Works

Innovation is essential in the construction industry, but current practices often focus narrowly on specific aspects rather than taking a comprehensive approach. To address this, systematic innovation through business model innovation (BMI) is proposed to enhance overall performance. Despite increasing interest in BMI research, it remains in its early stages, lacking quantitative analysis of its impact on business model components. This paper develops a framework using system dynamics to assess changes to a construction company's BM when faced with a variety of innovations across various projects. This shall be accomplished by (1) establishing factors and their relationships that define a …


A Systematic Review Of Phenotypic And Epigenetic Clocks Used For Aging And Mortality Quantification In Humans, Brandon Warner, Edward Ratner, Anirban Datta, Amaury Lendasse Jan 2024

A Systematic Review Of Phenotypic And Epigenetic Clocks Used For Aging And Mortality Quantification In Humans, Brandon Warner, Edward Ratner, Anirban Datta, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

Aging is the leading driver of disease in humans and has profound impacts on mortality. Biological clocks are used to measure the aging process in the hopes of identifying possible interventions. Biological clocks may be categorized as phenotypic or epigenetic, where phenotypic clocks use easily measurable clinical biomarkers, and epigenetic clocks use cellular methylation data. In recent years, methylation clocks have attained phenomenal performance when predicting chronological age and have been linked to various age-related diseases. Additionally, phenotypic clocks have been proven to be able to predict mortality better than chronological age, providing intracellular insights into the aging process. This …


A Model-Adaptive Random Search Actor Critic: Convergence Analysis And Inventory-Control Case Studies, Yuehan Luo, Jiaqiao Hu, Abhijit Gosavi Jan 2024

A Model-Adaptive Random Search Actor Critic: Convergence Analysis And Inventory-Control Case Studies, Yuehan Luo, Jiaqiao Hu, Abhijit Gosavi

Engineering Management and Systems Engineering Faculty Research & Creative Works

Reinforcement learning (RL) is an exciting area within the domain of Markov Decision Processes (MDPs) in which the underlying optimization problem is solved either in a simulator of the real-world system or via direct interaction with the real-world system, when its underlying transition probabilities are difficult to estimate. The latter is commonly true of large-scale, real-world MDPs with complex underlying transition dynamics. RL is currently being widely researched in the world of medicine/neuroscience after some spectacular success stories demonstrating super-human behavior in computer games. In this paper, we propose a new actor-critic-based RL algorithm for approximately solving continuous state/action MDPs …


The Impact Of Journalistic Cultures On Social Media Discourse: Us Primary Debates In Cross-Lingual Online Spaces, Lea Hellmueller, Lindita Camaj, Sebastián Vallejo Vera, Peggy Lindner Jan 2024

The Impact Of Journalistic Cultures On Social Media Discourse: Us Primary Debates In Cross-Lingual Online Spaces, Lea Hellmueller, Lindita Camaj, Sebastián Vallejo Vera, Peggy Lindner

Engineering Management and Systems Engineering Faculty Research & Creative Works

This cross-lingual project examines how social media posts of Spanish- and English-language media impact incivility in user comments during the 2020 primary political debates in the United States. We analyzed Facebook posts of news organizations that hosted the debates and used a state-of-the-art machine-learning model to analyze the corresponding comments. Our findings reveal distinct journalistic cultures on the post-level: English-language media are significantly more likely to use interpretation while Spanish-language media employ more audience-engagement and factual reporting strategies. We argue that in order to understand incivility in social media discourse during political debates, we need to consider journalistic cultures: While …


Enhancing Writing Quality And Self-Efficacy Beliefs Through Process-Oriented Task-Based Instruction And Multiple Feedback Forms, Samira Moussaoui Jan 2024

Enhancing Writing Quality And Self-Efficacy Beliefs Through Process-Oriented Task-Based Instruction And Multiple Feedback Forms, Samira Moussaoui

Journal of Educational and Psychological Studies

Abstract:This article presents the research findings of a quasi-experimental study seeking to enhance the writing quality and self-efficacy beliefs of Algerian undergraduate learners. The study employed task-based writing instruction within the process approach framework, and various forms of formative feedback (self-, peer-, and teacher feedback). The sample comprised 24 English as a foreign language (EFL) undergraduate learners with an intermediate level in academic writing. Data were collected through pre- and post-intervention writing tests to assess the participants’ writing quality, as well as pre- and post-intervention surveys, along with post-hoc interviews, to measure their writing self-efficacy levels. The analysis of the …


Characterizing The Extent And Nature Of Digital Food And Beverage Marketing In Singapore – A Descriptive Study, Xin Hui Chua, Clare Whitton, Stefanie Vandevijvere, Bridget Kelly, Rob M. Van Dam, Salome A. Rebello Jan 2024

Characterizing The Extent And Nature Of Digital Food And Beverage Marketing In Singapore – A Descriptive Study, Xin Hui Chua, Clare Whitton, Stefanie Vandevijvere, Bridget Kelly, Rob M. Van Dam, Salome A. Rebello

Research outputs 2022 to 2026

Objective: To characterize the nature of digital food and beverage advertising in Singapore Setting: Food and beverage advertisements within 20 clicks on top 12 non-food websites and all posts on Facebook and Instagram pages of 15 major food companies in Singapore were sampled from January 1 to June 30, 2018. Design: Advertised foods were classified as being core (healthier), non-core or mixed-dishes (example burger) using the WHO nutrient profile model and national guidelines. Marketing techniques were assessed using published coding frameworks. Participants: NA Results: Advertisements (n=117) on the 12 non-food websites were largely presented as editorial content. Food companies posted …


A Structure From Motion Photogrammetric Method For Continuously Measuring And Tracking The Deformations Of Soils During Triaxial Testing, Xiaolong Xia Jan 2024

A Structure From Motion Photogrammetric Method For Continuously Measuring And Tracking The Deformations Of Soils During Triaxial Testing, Xiaolong Xia

Doctoral Dissertations

"Measuring soil deformation characteristics during triaxial testing is an important part of characterizing the stress-strain behavior of both saturated and unsaturated soils. The total and local deformations and volume changes of a soil specimen are indispensable parameters that need to be measured and are of great significance for understanding volume change and shear strength characteristics of the soil. Over the past several decades, numerous efforts have been made to measure the soil deformations during triaxial testing. However, it remains a great challenge for researchers to measure the volume-changes of unsaturated soils due to the existence of the air phase.

This …


Comprehensive Investigation Of Using Tire-Derived Aggregate In Chip Seal Subjected To Various Traffic And Environmental Conditions, Alireza Pourhassan Jan 2024

Comprehensive Investigation Of Using Tire-Derived Aggregate In Chip Seal Subjected To Various Traffic And Environmental Conditions, Alireza Pourhassan

Doctoral Dissertations

"Chip seal is one of the most cost- and performance-effective pavement preservation treatments commonly used in the United States. Using crumb rubber obtained from scrap tires as a partial or full replacement for mineral aggregate has been proposed as a sustainable solution to reduce the negative environmental impacts of scrap tire accumulation and excessive consumption of natural resources. However, there was no data available regarding the performance of rubberized chip seal under traffic loads and environmental conditions. An extensive study using laboratory specimens and conditioning as well as field implementation and assessments were conducted to bridge this gap. Different traffic …


Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel Jan 2024

Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel

Doctoral Dissertations

"Current energy prices, national energy security, and global climate change fuel our momentum to find efficient advanced fuels choices. In this study, biodiesel processing, and a novel design for next generation biodiesel plants are explored. During a National Science Foundation (NSF) I-Corps project we identified three creative and profitable improvements to the process: 1. Incorporating Energy intensive separations and reactions 2. Utilizing Low commodity glycerol and 3. Applying process intensification principles.

Current biodiesel processes are catalyzed processes using continuous stir reactors with distillation systems to separate material constituents. We tested a lab-scale nocatalyst supercritical biodiesel process using waste cooking oil …


Characterization Of The Acquisition Parameters Of A Submersible Gamma-Ray Computed Tomography System, Zhongmin Jin Jan 2024

Characterization Of The Acquisition Parameters Of A Submersible Gamma-Ray Computed Tomography System, Zhongmin Jin

Doctoral Dissertations

"The purpose of this work is to study a component of a submersible gamma-ray computed tomography (CT) system used in the non-destructive testing of irradiated nuclear fuels. The first section of this study proposes two acceleration approaches for rapidly modeling a transmission-type gamma-ray tomography system. The first relies on Monte Carlo simulations with a monodirectionally biased source sampled from a sub-volume of the whole source volume. This method estimates the real count rate using analytical correction factors. The second way of acceleration is based on deterministic calculations that use the Beer-Lambert law and detector response characteristics. It shows that both …


Advancing A Systems Perspective On Innovative Behavior, Stephen Demski Jan 2024

Advancing A Systems Perspective On Innovative Behavior, Stephen Demski

Doctoral Dissertations

"Engineering organizations pursue innovation in strategy, structure, processes, and the services and products offered to remain relevant and competitive. Identifying factors supporting or constraining innovative work behavior and recognizing the complexity of their interactions are vital to sustaining an innovative workforce, yet how factors interact has not been comprehensively studied.

Recognizing innovative work behavior as the output of a complex system of factors guided this study’s literature search that identified over one hundred individual, team, and organizational factors influencing innovative behavior, interviews of engineers to learn what factors are essential in their work environment, and Delphi survey to rank factors, …


Novel Uses Of Distributed Optical Fiber Sensing For Geo-Mechanical Monitoring, Samuel Vincent Nowak Jan 2024

Novel Uses Of Distributed Optical Fiber Sensing For Geo-Mechanical Monitoring, Samuel Vincent Nowak

Doctoral Dissertations

"Rock mass monitoring in underground excavations is crucial for ensuring workplace safety and efficiency. As mines become deeper and more complex, the need to monitor larger volumes of rock during mining becomes impractical with existing instruments due to high costs. Distributed Optical Fiber Sensing (DOFS) is a powerful technology with advantages like long sensor length, real-time measurement capabilities, ease of installation, low cost, and distributed measurement. However, its application in rock mass monitoring is limited, especially in the mining industry. This study addresses a major gap in DOFS technology, specifically the inability of long-range distributed optical fiber strain sensors to …


Monitoring And Control Of Coal Dust Exposure Using Low-Cost Pm Sensors And Computational Fluid Dynamics, Nana Kobina Amoako Amoah Jan 2024

Monitoring And Control Of Coal Dust Exposure Using Low-Cost Pm Sensors And Computational Fluid Dynamics, Nana Kobina Amoako Amoah

Doctoral Dissertations

"Overexposure to respirable coal mine dust has been linked to causing serious health problems including coal workers pneumoconiosis (CWP) and chronic massive fibrosis. The prevalence of these health problems has been on the increase since the 2000s due to increased exposure levels with roof bolter operators having the highest exposure levels. The currently used PDM3700 is too expensive, heavy and bulky which limits their use only for regulatory monitoring failing to measure miners’ personal exposure levels. Also, since roof bolter operators are more prone to elevated coal dust levels, the canopy air curtain (CAC) was developed to protect then high …


Melt Pool Feature Extraction, A State-Space Model And Spatial Layer-To-Layer Control For Powder Bed Fusion, Xin Wang Jan 2024

Melt Pool Feature Extraction, A State-Space Model And Spatial Layer-To-Layer Control For Powder Bed Fusion, Xin Wang

Doctoral Dissertations

"Powder Bed Fusion (PBF) is an Additive Manufacturing (AM) technique which can reduce material waste and is a fast-prototyping technique for complex geometries. However, the lack of consistent quality is a major problem in industrial applications. An InfraRed (IR) camera is a common tool to monitor a surface temperature field and melt pool morphology in PBF. With melt pool features from camera videos, manufacturing researchers use spatial feature maps to visualize defect locations and control researchers use layer-to-layer control to achieve more uniform melt pools and less defects.

Paper I presents a simulation method to characterize the effect of down-sampling …


A Human-Centered Framework For Oncological Healthcare System Modeling Applied To Mobile Radiation Delivery, Alex Price Jan 2024

A Human-Centered Framework For Oncological Healthcare System Modeling Applied To Mobile Radiation Delivery, Alex Price

Doctoral Dissertations

"Healthcare systems engineering is challenging due to the complexity, geographic expansiveness, inertial properties, and the heterogeneous sub-systems, with varying vested interests. Additionally, humans comprise many of the forms and functions, and are independent, with resistance and uncertainty in their decision-making that adds complexity. Human-centered systems modeling approaches are therefore needed to capture this unique aspect of a healthcare system and to enhance understanding of emergent healthcare properties. This dissertation focuses on integrating systems modeling within healthcare and emphasizes the importance of incorporating human decision-making. Moreover, the incorporation of a human-centered approach yields particularly valuable insights into the decision-making processes that …


The Science Of Gravitational-Wave Sources And Beyond Compact Binary Coalescences, Yanyan Zheng Jan 2024

The Science Of Gravitational-Wave Sources And Beyond Compact Binary Coalescences, Yanyan Zheng

Doctoral Dissertations

"This work focuses on the field of gravitational-wave astronomy by extending the scope of detectable sources beyond compact binary coalescences, All the gravitational-wave detections so far come from compact binary coalescences. Focusing on core-collapse supernovae as promising sources for short gravitational-wave transients, this work reports optically targeted searches for gravitational-wave emitted by core-collapse supernovae during the third observing run of the LIGO and Virgo detectors. It also predicts the search sensitivity for the ongoing fourth and forthcoming fifth observing runs. Moreover, the work introduces a novel computational framework for testing the spatial distribution of binary black hole sources, allowing for …


Contextualizing Renewable Energy Adoption: An Examination Of The Role Of Community Choice Aggregation, Ankit Agarwal Jan 2024

Contextualizing Renewable Energy Adoption: An Examination Of The Role Of Community Choice Aggregation, Ankit Agarwal

Doctoral Dissertations

"The rapid expansion of renewable energy generation in the U.S., both through distributed and utility-scale facilities, is largely driven by top-down policy measures and the growing engagement of residential consumers on both individual and community levels. Previous studies on motives behind residential renewable energy adoption have examined procurement options in isolation and within a static context, primarily focused on intrinsic attributes like economic incentives, emission reductions, and peer popularity. This research introduces a novel context, assessing renewable procurement options in the presence of Community Choice Aggregation (CCA), a more prevalent and accessible alternative. This dissertation makes four pivotal contributions, offering …


Low-Shrinkage Fiber-Reinforced Concrete For Infrastructure Construction And Rehabilitation, Jingjie Wei Jan 2024

Low-Shrinkage Fiber-Reinforced Concrete For Infrastructure Construction And Rehabilitation, Jingjie Wei

Doctoral Dissertations

"The aim of this study is to develop two classes of low-shrinkage high-performance concrete (HPC): fiber-reinforced super workable concrete (FR-SWC) for infrastructure construction and fiber-reinforced self-consolidating concrete (FR-SCC) for repair applications. HPC with excess content of shrinkage mitigation materials (SMMs), including shrinkage-reducing admixture (SRA), superabsorbent polymer (SAP), and expansive agent (EA) has a detrimental effect on mechanical performance. These classes of HPC were optimized to reduce shrinkage, enhance mechanical properties, and improve durability. The effect of fiber type (macro synthetic fiber, MSF; 5D steel fiber, 5D; 80% 3D + 20% short steel fibers; STST), SMMs, and plastic viscosity on bond …


The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge Jan 2024

The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge

Doctoral Dissertations

"High viscosity friction reducers (HVFRs) have been recently gaining more attention and increasing in use, not only as friction-reducing agents but also as proppant carriers. Reusing of produced water has also been driven by both environmental and economic benefits. Currently, most friction reducers on the market are anionic friction reducers, which are fully compatible with most produced water with low to medium level of Total Dissolved Solids (TDS) but show a significant drop at high TDS conditions in term of their friction reduction performance in most cases. On the contrary, cationic friction reducers are believed to have better TDS tolerance …


Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications, Neila Pederneira Jan 2024

Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications, Neila Pederneira

Doctoral Dissertations

"In the past decade, a big interest has drawn into nanoporous metal-organic frameworks (MOFs) and silica-based materials as nanocarriers for drug delivery applications, owing to their exceptionally high surface area and highly structured porous network. The overall goal of this research was to optimize the pharmacokinetic behavior of several highly porous biocompatible drug carriers that have the potential to carry Ibuprofen, 5-Fluorouracil, and Curcumin to the desired tissue without creating a burst effect and minimizing the amount of dosage and size that conventional capsules require. The specific objectives of this study are to (i) assess the effect of drug solubility …


Additive Manufacturing Of Steel And Aluminum Structures: Modeling And Experiments, Manoj Kumar Reddy Rangapuram Jan 2024

Additive Manufacturing Of Steel And Aluminum Structures: Modeling And Experiments, Manoj Kumar Reddy Rangapuram

Doctoral Dissertations

"Additive manufacturing (AM) is defined as the process of joining materials to make objects from three-dimensional model data. Complex geometries can be easily manufactured compared to conventional subtractive methods with more freedom and flexibility in the design process. As the demand for AM process increased, it has become critical to understand the process and various parameters that constitute in affecting the quality of the manufactured part. Conducting experiments can be time intensive and costly to optimize a process. Modeling can be used as an aid to optimize, examine, and predict the process outcome.

The objective of this study is (i) …


Integrated Study Of Heat Transfer And Local Gas Dynamics In A Pebble Bed Very High Temperature Nuclear Reactor Using Advance Measurement Techniques, Muhna N. Alshammari Jan 2024

Integrated Study Of Heat Transfer And Local Gas Dynamics In A Pebble Bed Very High Temperature Nuclear Reactor Using Advance Measurement Techniques, Muhna N. Alshammari

Doctoral Dissertations

"The aim of this study, pebbles of diameter of 5 cm and a pebble-to-diameter ratio (aspect ratio) of 6 were used. In part I, the local gas velocities were studied at different radial and axial locations in the pebble bed using a sophisticated hot wire anemometry (HWA) technique, which was supported with a novel probe-protector case to protect the fragile probe, allowing the measurements to be taken between the pebbles for the first time. The local gas velocities were found to be significantly higher in the near wall region due to the higher void fractions in the near-wall region, compared …