Engineering Commons^™

The Impact Of Pac-Loaded Polymer Membrane Thickness On Chloroform Removal And Comparison Of Solvent And Thermal Membrane Regeneration Methods, Yizhi Hou, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Powdered activated carbon (PAC) has better adsorption performance than granular activated carbon (GAC) and is widely used in water purification. In most cases, PAC is dosed into water directly, then precipitated as sludge, and landfilled. In this study, PAC was mixed with a polymer and dissolved in dimethylformamide (DMF) solvent to form a PAC-loaded membrane, which was then tested for chloroform removal. The chloroform adsorption capacity of the PAC membrane increased with increasing membrane thickness because of higher carbon loading. However, regardless of membrane thickness, the flux of the PAC membranes was similar since flux resistance predominantly occurred at the …

Exploring Performance-Based Contracts: A Good Option To Address Long-Term Road Maintenance In California?, Maria Calahorra-Jimenez, Richard Poythress

Mineta Transportation Institute

Performance-based contracts (PBCs) used in road maintenance provide flexibility for considering new materials, design, and technology to achieve predetermined performance targets. Several states in the U.S. have already used these types of contracts in road maintenance, and their experience can inform the use of PBCs in California. The objectives of this research are twofold. First, identify the benefits and challenges of PBCs compared to traditional contracts. Second, explore the main aspects of PBCs implementation for road maintenance and relate them to California's context. To this end, deductive-inductive content analysis was conducted on 84 peer-reviewed articles published between 1998 and 2023. …

Battery Management System Development For Electric Vehicles And Fast Charging Infrastructure Improvement, Yu Yang, Hen-Geul Yeh, Cesar Ortiz

Mineta Transportation Institute

The electric vehicle (EV) has become increasingly popular due to its being zero-emission. However, a significant challenge faced by EV drivers is the range anxiety associated with battery usage. Addressing this concern, this project develops a more efficient battery management system (BMS) for electric vehicles based on a real-time, state-of-charge (SOC) estimation. The proposed study delivers three modules: (1) a new equivalent circuit model (ECM) for lithium-ion batteries, (2) a new SOC estimator based on the moving horizon method, and (3) an on-board FPGA implementation of the classical Coulomb counting method for SOC estimation. The research team extends the traditional …

Adopt: An Environmentally-Friendly System For Alerting Drivers To Occluded Pedestrians Traffic, Abrar Abdulrahman Alali

Computer Science Theses & Dissertations

The emergence of sensing technologies and vehicular communications has brought significant opportunities for enhancing pedestrian safety on city streets. However, existing solutions rely on costly technologies such as computer vision and trajectory prediction to detect crossing pedestrians, while they have limits in detecting pedestrians who are occluded by parked cars. Despite the presence of collaborative perception by surrounding vehicles and infrastructure, there is a notable absence of incorporating existing parked cars themselves due to their insufficiency in detecting pedestrians and communicating with other cars while they are turned off. Furthermore, accommodating pedestrians on streets has been linked to an additional …

Innovative 4d Printing Of Biomimetic Collagen-Tcp Scaffolds For Bone Regeneration, Karly Morgan Liebendorfer

Theses and Dissertations

Bone tissue engineering (BTE) is a promising alternative approach to autografts and allografts when treating various bone diseases and disorders. BTE enables the fabrication of biocompatible, biomimetic, and osteo-stimulating constructs for the repair and regeneration of damaged bone tissue. The native bone environment primarily consists of anisotropic type 1 collagen (organic) and hydroxyapatite nanocrystals (inorganic). Composite biomimetic scaffolds fabricated by combining collagen with bioceramics have shown immense promise for BTE applications. Prior work has reported on different biofabrication methods to synthesize collagen-based composite scaffolds for use in BTE applications. However, to date, a customizable 3D composite scaffold that resembles the …

Dynamic Metabolic Flux Analysis Amidst Data Variability: Sphingolipid Biosynthesis Case Study In Arabidopsis Thaliana Cell Cultures, Abraham Boluwatife Osinuga

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Sphingolipids are pivotal for plant development and stress responses. Growing interest has been directed towards fully comprehending the regulatory mechanisms of the sphingolipid pathway. In this study, we explore its de novo biosynthesis and homeostasis in Arabidopsis thaliana cell cultures, shedding light on fundamental metabolic mechanisms. Employing ¹⁵N isotope labeling and quantitative dynamic modeling approach, we obtained data with notable variations and developed a regularized and constraint-based Dynamic Metabolic Flux Analysis (r-DMFA) framework to predict metabolic shifts due to enzymatic changes. Our analysis revealed key enzymes such as sphingoid-base hydroxylase (SBH) and long-chain-base kinase …

Growth And Simulation Of Dielectric-Metal Nanoheterostructured Thin Films By Ballistic Deposition, Shawn Wimer

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

This thesis is divided into two related topics: the structural and chemical characterization of dielectric-metal nanoheterostructured thin films grown by glancing angle deposition (GLAD) and the results of the simulated growth of films and structures by GLAD with discrete-space and continuous-space Monte Carlo ballistic simulation.

Individual structures comprising films grown by GLAD were investigated by S/TEM and SEM imaging, electron diffraction, and chemical characterization and mapping by EDX. Different intermolecular interactions within and between different materials, including Si, Ag, Au, and ZrO₂, are linked to differences in the shapes of individual materials in heterostructures, the shape of heterostructures …

Modelling, Design, Control, And Implementation Of Advanced Isolated Dc/Dc Converters For Renewable Energy Applications, Yuqi Wei, Quanming Luo, Di Mou, Shuang Zhao, Marco Liserre, H. Alan Mantooth

Electrical Engineering and Computer Science Faculty Publications and Presentations

Demand for high-efficient isolated DC/DC converters to achieve energy transfer among renewable energy sources, energy storage elements, and loads is increasing because of renewable energies’ increasing market penetration. Traditional converters pose significant challenges due to the wide voltage range operation nature of these components. Interest in improving the power converters’ performances for renewable energy applications is growing rapidly. Researchers are exploring accurate analysis methods, optimal design, and novel control strategies to improve the power converters’ performance. These strategies can improve the converters’ performance without any modifications to the traditional hardware. In addition, design automations are drawing more and more attention. …

Experimental Study On The Detection Of The Existence And Location Of Mimicked And Unexpected Interface Debonding Defects In An Existing Rectangular Cfst Column With Pzt Materials, Qian Liu, Bin Xu, Genda Chen, Weilong Ni, Zhixun Liu, Chun Lin, Zhiyou Zhuang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Interface bonding conditions between concrete and steel materials play key roles in ensuring the composite effect and load-carrying capacity of concrete–steel composite structures such as concrete-filled steel tube (CFST) members in practice. A method using both surface wave and electromechanical impedance (EMI) measurement for detecting the existence and the location of inaccessible interface debonding defects between the concrete core and steel tube in CFST members using piezoelectric lead zirconate titanate (PZT) patches as actuators and sensors is proposed. A rectangular CFST specimen with two artificially mimicked interface debonding defects was experimentally verified using PZT patches as the actuator and sensor. …

Synergetic Effect Of Viscosity Modifying Admixtures And Polycarboxylate Ether Superplasticizer On Key Characteristics Of Thixotropic Uhpc For Bonded Bridge Deck Overlay Rehabilitation, Le Teng, Ming Jin, Jiadi Du, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Thin bonded ultra-high-performance concrete (UHPC) overlay is an advanced technology for bridge deck rehabilitation. UHPC should be tailored to secure adequate flowability and high thixotropy to facilitate mixing and placement with a low risk of sagging of the material on sloped bridge deck surfaces. The synergetic effect between nano clay (NC) and polycarboxylate ether (PCE) superplasticizer or cellulose-based viscosity modifying admixture (VMA) and PCE on the rheological properties (yield stress, plastic viscosity, and thixotropy), cement hydration, autogenous shrinkage, compressive strength, and porosity was systematically investigated. The bond strength between conventional concrete (CC) representing existing bridge deck concrete and thixotropic UHPC …

In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The emergence of 2D materials has significantly expanded the wide range of nanomaterials with diverse applications. Notably, their high conductivity, catalytic efficiency, and hydrophobicity have fueled heightened research interests for water treatment applications. This research aimed to investigate the synthesis and characterization of MXene and reduced graphene oxide (rGO) nanocomposites with silver nanoparticles (Ag) for enhanced catalytic activity in the decomposition of Direct Blue-24 dye. In this study, we employed well-established methods, previously documented in the literature, to prepare two distinct nanocomposites. Novel nanocomposites, namely reduced graphene oxide–silver nanoparticles (rGO–Ag) and MXene–silver nanoparticles (MXene–Ag), were synthesized using the hydrothermal and …

Predicting Iot Distributed Ledger Fraud Transactions With A Lightweight Gan Network, Charles Rawlins, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Decision-making and consensus in traditional blockchain protocols is formulated as a repeated Bernoulli trial that solves a computationally intense lottery puzzle, called Proof-of-Work (PoW) in Bitcoin. This approach has shown robustness through practice but does not scale with increasing network size and generation of new transactions. Resource constrained Internet of Things (IoT) networks are incompatible with full computation of schemes like Bitcoin's PoW. Our effort proposes a first step towards an alternative consensus using machine learning-based decision-making with prediction of fraud transactions to alleviate need for intense computation. To improve base approval probabilities for fraud detection in an ideal security …

In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The emergence of 2D materials has significantly expanded the wide range of nanomaterials with diverse applications. Notably, their high conductivity, catalytic efficiency, and hydrophobicity have fueled heightened research interests for water treatment applications. This research aimed to investigate the synthesis and characterization of MXene and reduced graphene oxide (rGO) nanocomposites with silver nanoparticles (Ag) for enhanced catalytic activity in the decomposition of Direct Blue-24 dye. In this study, we employed well-established methods, previously documented in the literature, to prepare two distinct nanocomposites. Novel nanocomposites, namely reduced graphene oxide–silver nanoparticles (rGO–Ag) and MXene–silver nanoparticles (MXene–Ag), were synthesized using the hydrothermal and …

Freezing-Thawing Hysteretic Behavior Of Soils, Jidong Teng, Antai Dong, Sheng Zhang, Xiong Zhang, Daichao Sheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The soil freezing characteristic curve (SFCC) plays a crucial role in investigating the soil freezing-thawing process. Due to the challenges associated with measuring the SFCC, there is a shortage of high-quality or rigorous test results with sufficient metadata to be effectively used for applications. Current researchers typically conduct freezing tests to measure the SFCC and assume a singular SFCC when studying the freezing-thawing process of soils, although limited studies indicated that there is a hysteresis during the freezing and thawing process. In this paper, a series of freezing-thawing tests were performed to assess the SFCC, utilizing a precise nuclear magnetic …

Building Sevices Engineering July/August 2024

Building Services Engineering

No abstract provided.

Optical Frequency Domain Reflectometry-Based High-Performance Distributed Sensing Empowered By A Data And Physics-Driven Neural Network, Zhaopeng Zhang, Wei Peng, Osamah Alsalman, Lingmei Ma, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Optical frequency domain reflectometry (OFDR) based distributed strain sensors are the preferred choice for achieving accurate strain measurements over extensive sensing ranges while maintaining exceptional spatial resolution. However, the simultaneous realization of high spatial resolution, high strain resolution, large strain range, and an extended sensing range presents an exceedingly challenging endeavor. In this study, we introduce and experimentally demonstrate a data and physics-driven neural network-empowered OFDR system designed to attain high-performance distributed sensing. In our experiments, we successfully maintained an impressive sensing resolution of sub-microstrain (0.91 µε) alongside a sharp spatial resolution of sub-millimeter (0.857 mm) across a 140-m sensing …

Safe And Efficient Operation Of Mobile Robots In Indoor Environments: A User-Centric Shared Control System With High-Level Navigation Capabilities, Ahmet Saglam

Electrical & Computer Engineering Theses & Dissertations

Hospitalization and isolation can be a traumatic experience for immunocompromised children, especially because they are separated from their families and friends. Social robots have been proposed as a way to improve the quality of care for children hospitalized in isolation by providing alternative means of social interaction and support. Remote control of such robots in a hospital setting, particularly where safety is a major concern, can be a daunting task for young patients.

This dissertation introduces a multilevel shared control system for mobile robots, specifically companion robots in hospital-like indoor spaces. The system integrates user inputs with algorithmic semi-autonomous control …

Auxiliary Diagnosis Of Dental Calculus Based On Deep Learning And Image Enhancement By Bitewing Radiographs, Tai Jung Lin, Yen Ting Lin, Yuan Jin Lin, Ai Yun Tseng, Chien Yu Lin, Li Ting Lo, Tsung Yi Chen, Shih Lun Chen, Chiung An Chen, Kuo Chen Li, Patricia Angela R. Abu

Ateneo Laboratory for Intelligent Visual Environments

In the field of dentistry, the presence of dental calculus is a commonly encountered issue. If not addressed promptly, it has the potential to lead to gum inflammation and eventual tooth loss. Bitewing (BW) images play a crucial role by providing a comprehensive visual representation of the tooth structure, allowing dentists to examine hard-to-reach areas with precision during clinical assessments. This visual aid significantly aids in the early detection of calculus, facilitating timely interventions and improving overall outcomes for patients. This study introduces a system designed for the detection of dental calculus in BW images, leveraging the power of YOLOv8 …

Engine Performance Of An Electric Airplane With Partial Battery Capability, Hannah Yasmine Scrivens

Theses and Dissertations

As electric aircraft are developed and certified, knowledge of electric aircraft performance during complete or partial battery failures can be useful to determine an aircraft’s limitations and capabilities of completing an emergency landing, especially during takeoff and low-altitude climbs, as well as fully characterizing the potential aircraft performance. The results of this research will be useful in developing regulations and procedures pertaining to energy reserves and emergencies. This paper presents the results of a Pipistrel electric airplane climb power ground test that was conducted by the author and Florida Tech faculty. In the test, one of the airplane’s batteries was …

The Logical Implications Of Open Public Data: Examining The Current Situation, Reviewing The Problems And Advancing The Rule Of Law, Yanlei Cheng, Lin Zhang, Xu Zhang

Journal of Scientific Information Research

[Purpose/significance]Digital rule of law government is a new paradigm of government governance that is compatible with digital China and digital society. Data elements have become an important driving force for high-quality economic development in the era of digital, and public data openness is an important issue in the construction of digital rule of law government. [Method/process]In this paper, the regulations, policies and technical standards of the central government and 10 provinces, including Zhejiang, Shandong, Guizhou, Guangdong, Sichuan, Fujian, Guangxi, Hainan, Jiangxi and Jiangsu as research samples to examine the current system of regulations and policies on the opening up of …

Privacy-Preserved Data Trading Via Verifiable Data Disturbance, Man Zhang, Xinghua Li, Yanbing Ren, Bin Luo, Yinbin Miao, Ximeng Liu, Robert H. Deng

Research Collection School Of Computing and Information Systems

To motivate data owner (DO) to trade data, the existing data trading allows DO to sell the disturbed data to the data consumer (DC), where the disturbance parameter and the data price are negotiated by them, and DO independently adds the disturbance noise to data (usually continuous type) following the negotiation result. However, DOs may violate the negotiated parameter and add more noise to data while obtaining the negotiated price, which damages DC's disturbed data availability. This deficiency is rooted in the absence of supervision and verifiability on DOs’ independent disturbances. Aiming at the above problem, we devise a privacy-preserved …

Carbon-Based Nanocomposite Membranes For Membrane Distillation: Progress, Problems And Future Prospects, Chhabilal Regmi, Yuwaraj K. Kshetri, S. Ranil Wickramasinghe

Chemical Engineering Faculty Publications and Presentations

The development of an ideal membrane for membrane distillation (MD) is of the utmost importance. Enhancing the efficiency of MD by adding nanoparticles to or onto a membrane’s surface has drawn considerable attention from the scientific community. It is crucial to thoroughly examine state-of-the-art nanomaterials-enabled MD membranes with desirable properties, as they greatly enhance the efficiency and reliability of the MD process. This, in turn, opens up opportunities for achieving a sustainable water–energy–environment nexus. By introducing carbon-based nanomaterials into the membrane’s structure, the membrane gains excellent separation abilities, resistance to various feed waters, and a longer lifespan. Additionally, the use …

Impact Of Non-Thermal Plasma Generated Using Air And Nitrogen On Functional Properties Of Milk Protein Dispersions, Nikitha Modupalli, Md Mahfuzur Rahman

Food Science Faculty Publications and Presentations

This study focuses on improving the functionalities of milk protein concentrate (MPC) using a nonthermal plasma jet and plasma-activated water (PAW) with atmospheric air and nitrogen as source gases. The 5% and 10% MPC dispersions were directly treated with a plasma jet, and PAW was used to make the MPC dispersions. The dispersions were analyzed for changes in protein structure and functional properties. The treatment altered the secondary structure of MPC protein structure by increasing β-components and changing the order of random coils. The solubility of the PAW-treated 5% protein dispersions doubled due to plasma-induced modification of hydrophilic and covalent …

Patient-Specific Hemodynamic Modeling For Optimizing Left Ventricular Assist Device And Right Heart Health, Holly Felice Grant

Theses and Dissertations

LVAD speed optimization is essential for efficient LVAD therapy and to minimize complications. However, the ideal LVAD speed is unknown and must be tailored for each patient. The interplay between the LVAD, systemic, and pulmonary circulations is critical and should be considered during optimization. A computational hemodynamic model that can be tailored for each patient may provide clinicians with useful guidance and reduce the need for repeated invasive studies. This study sought to customize and evaluate a patient-specific LVAD hemodynamic optimization model.

We conducted a retrospective analysis on 25 patients implanted with HM3 and who underwent right heart catheterization (RHC) …

Wind Plant Wake Losses: Disconnect Between Turbine Actuation And Control Of Plant Wakes With Engineering Wake Models, Ryan Scott, Nicholas Hamilton, Raul Bayoan Cal, Patrick Moriarty

Mechanical and Materials Engineering Faculty Publications and Presentations

Wake losses from neighboring plants may become a major factor in wind plant design and control as additional plants are constructed in areas with high wind resource availability. Because plant wakes span a large range of physical scales, from turbine rotor diameter to tens of kilometers, it is unclear whether conventional wake models or turbine control strategies are effective at the plant scale. Wake steering and axial induction control are evaluated in the current work as means of reducing the impact of neighboring wind plants on power and levelized cost of electricity. FLOw Redirection and Induction in Steady State (FLORIS) …

Investigation Of Ethane Dehydrogenation And Hydrogenolysis On Pt(111), Pt(211) And Pt(100): Bayesian Quantification And Correction Of Dft-Based Enthalpic And Entropic Uncertainties, Mubarak Bello

Theses and Dissertations

Computational investigations of heterogeneously catalyzed reactions using density functional theory (DFT) are often inaccurate, largely due to uncertainties in the choice of DFT functional (enthalpic uncertainty) and approximations for modeling adsorbate movement along the catalyst surface (entropic uncertainty). This work illustrates that both uncertainties are significant in the investigation of the ethane dehydrogenation (EDH) and hydrogenolysis on Pt catalysts by considering the complete deconstruction of ethane on Pt(111), Pt(211), and Pt(100) using microkinetic modeling (MKM). Hence, this work uses both non-calibrated and Bayesian calibrated MKMs to quantify and correct inaccuracies in macroscopic properties due to both uncertainties. A Bayesian approach …

Improving Tcp Performance Using P4-Programmable Data Planes, Jose Antonio Gomez Gaona

Theses and Dissertations

The Transmission Control Protocol (TCP) forms the foundation of reliable end-to-end communication and is widely used by many applications for efficient data transfers across the Internet. TCP relies on various congestion control algorithms (CCAs) to manage its response to network congestion. These algorithms ensure fairness among competing flows and optimize the use of available bandwidth. However, since TCP is deployed within end hosts, its capacity to attain visibility of network events is constrained. This limitation arises from the closed nature of non-programmable network devices, which prevents researchers from exploring customized actions in response to network events. Recently, the emergence of …

Evaluating The Influence Of Evtol Pilot Interface Visual Density And Information Density On Pilot Situation Awareness, Workload, And Search Performance, Bhoomin Bhupendrabhai Chauhan

Theses and Dissertations

The purpose of the current study was to investigate the influence of levels of visual density (VD) and information density (ID) of an electrical vertical take-off and landing (eVTOL) aircraft pilot interface on pilot situation awareness (SA), workload, and search performance. An eVTOL aircraft is a novel aircraft design that is able to perform vertical take-off and landing similar to a rotorcraft and transition to a forward flight, similar to a fixed-wing aircraft. These aircraft are envisioned to operate in urban environments at lower altitudes, necessitating efficient, clear, and concise pilot interfaces to ensure safety and operational effectiveness. The study …

Study On Pilot Response Time To Reject Takeoff With One Engine Inoperative (Oei), Lydia Savitri Scrivens

Theses and Dissertations

The FAA regulation 14 CFR § 25.109 defines accelerate-stop testing for transport-category multiengine aircraft. It specifies that testing must include 2-second distance equivalent at engine failure speed VEF to simulate time taken for pilot to reject takeoff. However, pilot response time is widely debated. The purpose of this study is to determine pilot response time in rejecting a takeoff due to the failure of one engine during the takeoff roll.

Seven multiengine rated pilots participated in this study, which was conducted in a Baron 58 in the X-Plane 12 flight simulator. During the recruiting process, test subject candidates provided their …

An Integrated Space Test Lexicon: A Taxonomy For The Integrated Test And Evaluation Of Space Systems, Stephen K. Tullino, Andrew S. Keys, Robert A. Bettinger, Amy M. Cox, David R. Jacques

Faculty Publications

The proposed Integrated Space Test Lexicon is intended to amalgamate the numerous definitions of integrated (IT or IT&E), development test (DT or DT&E), and operational test (OT or OT&E) into unified, service-wide definitions, aligned with the Space Test Enterprise Vision. Refining such definitions will help distill the core characteristics of these fundamental test types to first identify space system activities composing what is traditionally known as DT and OT, then to provide a means of how these activities fit into the IT paradigm and support space system development. In forging a common understanding of how DT and OT support space …