Engineering Commons^™

Food Waste Crisis In The United States Of America: The Known, The Overlooked And The Undisclosed, Sagarika Srivastava, David J. Tonjes

Technology & Society Faculty Publications

With a loss of 1,250 calories per day per person or 140 kg/p/yr, the United States (U.S.) has a large problem with food waste. The later a product is wasted in the supply chain, the greater its environmental cost. Many food waste mitigation efforts focus on the retail and consumer stages, but there is also considerable food waste in the production phase, which includes growing, harvesting, transportation, storage and processing. The study is conducted in two steps: a bibliometric analysis of 218 articles on food waste in the U.S., followed by an investigation of options to meet food waste recovery …

Shifting Students’ Perceptions About Homelessness: Quantitative Assessment Of A Project-Based Approach, Diana A. Chen, Mark A. Chapman, Joel Alejandro Mejia

School of Engineering: Faculty Scholarship

Although engineering institutional bodies uphold public welfare and the impact of engineering on people and society, engineering curricula rarely scaffold students to connect their technical learning with sociotechnical perspectives. This paper describes a project-based learning approach where engineering students engaged with issues faced by people experiencing homelessness to better understand the sociotechnical nature of effective, user-centered, engineering design. We conducted a quantitative assessment to de- termine how well and in what ways the project-based learning curriculum shifted students’ perceptions about homelessness. We collected pre-/post-survey data from students on 21 statements about their perceptions and attitudes about homelessness prior to and …

Bio-Inspired Sutures: Localizing Damage By Isolating Strain Energy, Diana A. Chen, Melissa M. Gibbons

School of Engineering: Faculty Scholarship

This study draws upon bio-inspiration from anatomical sutures found in hard structures, such as turtle shells, to explore if impact energy can be dissipated through geometric parameterization rather than relying on energy-absorbing materials. While previous finite element analysis studies identified optimal dovetail suture geometries for maximizing the global stiffness and toughness of archway structures, this paper explores how different suture geometries might optimize localization effects through segmentation to isolate damage caused by the propagation of strain energy. We compare the global toughness of each suture geometry to its scaling factor, defined as the ratio of strain energy in the center …

Extended-Duration Satellite Testing Via Altitude-Controlled High-Altitude Balloon, Drew Early, Evan Champney, Nikki Allen, Riley Galatis, Lukas Hezel, Joseph Kloess, Andrew Donnell, Sam Whitlock, Kaden Queener

Von Braun Symposium Student Posters

Undergraduate runner-up, 2025 Von Braun Symposium Student Poster Contest

Molecular Dynamics-Based Two-Dimensional Simulation Of Powder Bed Additive Manufacturing Process For Unimodal And Bimodal Systems, Yeasir Mohammad Akib, Ehsan Marzbanrad, Farid Ahmed

Manufacturing & Industrial Engineering Faculty Publications

The trend of adapting powder bed fusion (PBF) for product manufacturing continues to grow as this process is highly capable of producing functional 3D components with micro-scale precision. The powder bed’s properties (e.g., powder packing, material properties, flowability, etc.) and thermal energy deposition heavily influence the build quality in the PBF process. The packing density in the powder bed dictates the bulk powder behavior and in-process performance and, therefore, significantly impacts the mechanical and physical properties of the printed components. Numerical modeling of the powder bed process helps to understand the powder spreading process and predict experimental outcomes. A two-dimensional …

Influence Of Alloy Composition On The Process Robustness Of Steels Consolidated Via Laser-Directed Energy Deposition, Jonathan Kelley

Masters Theses

"To ensure consistent quality of additively manufactured parts, it is advantageous to identify alloys which can meet performance criteria while being robust to process variations. Toward this end, this work investigated the effect of alloy composition on the robustness of steels consolidated via laser-directed energy deposition (L-DED). Ultra-high-strength low-alloy steel (UHSLA) and pure iron powders were mixed in-situ to produce 10 compositions containing 10-100% UHSLA by mass. JMatPro material simulations roughly predicted phases and mechanical properties. Two sets of experiments were used to evaluate the sensitivity of as-built hardness (all 10 compositions) and tensile properties (5 select compositions) to process …

Introducing Catalizer: A Framework For Prototyping Models Of Biological Systems, Andy M. Day

Honors Theses

Modeling the light response system of Nannochloropsis oceanica brings

a set of challenges that make modeling difficult. Notably, potential models

may contain a large number of chemical species. A large number of

species creates a quadratic explosion in the number of potential pathways.

In addition, mathematically defining these pathways is error prone, yet

follows a surprising simple set of rules. We seek to create a domain specific

language which can precisely define these chemical reaction networks.

Once the networks have been defined, they can be exported as procedures

defined in popular programming languages for further analysis.

Salinity Effects On Cu(Ii) Bioremediation By Chlamydomonas Reinhardtii Microalgae, Jennifer Hughes

Honors Undergraduate Theses

Microalgae offer a sustainable approach to wastewater treatment by removing pollutants such as excess nutrients, CO₂, and heavy metals. Among various species, Chlamydomonas reinhardtii shows strong potential in removing Cu(II) ions from wastewater. In addition, salinity stress in C. reinhardtii has been linked to morphological and metabolic changes that enhance lipid and phytochemical production. While salinity stress has been studied for enhancing biofuel production, its impact on microalgal removal of heavy metals, particularly Cu(II), remains largely unexplored. Understanding how varying salinity conditions affect both algal growth and the efficiency of Cu(II) remediation could provide critical insights for improving integrated wastewater …

Cultivating Plain Language Skills For Engineering Students, Catherine Wong, Cynthia Carlson

Faculty Publications

While engineers are learning the vocabulary of the profession, understandably, they want to practice, and perhaps show their professors that they are proficient. This leads to student writing that is overly complicated and full of jargon. This is not the type of document that would be clear to the public, or even to a professional outside of the narrowly focused field of the particular engineer. After graduation, engineers’ writing becomes exponentially more important. Often approval of projects relies on residents’ or clients’ understanding of engineers’ work. For example, an engineering firm completing an investigation of an important health concern such …

Mastering Enterprise Networks (2nd Ed), Mathew J. Heath Van Horn

OER Main

Mastering Enterprise Networks, is a comprehensive guide to building, defending, and attacking enterprise networks. It covers a wide range of topics, from network fundamentals to advanced security concepts. The book is well-organized and easy to follow, making it a valuable resource for both beginners and experienced network professionals.

One of the strengths of this book is its focus on hands-on learning. The book includes 50 chapters of labs that allow readers to practice the concepts they have learned. These labs are a great way to reinforce your understanding of enterprise networks while developing practical skills.

This book covers security from …

Tidal Flooding Contributes To Eutrophication: Constraining Nonpoint Source Inputs To An Urban Estuary Using A Data Driven Statistical Model, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Sophie Clayton, Peter W. Bernhardt, Thomas R. Allen

OES Faculty Publications

In coastal urban areas, tidal flooding brings water carrying nutrients and particles back from land to estuarine and coastal waters. A statistical model to predict nutrient loads during tidal flooding events can help estimate nutrient loading from previous and future flooding events and adapt nutrient reduction strategies. We measured concentrations of dissolved inorganic nitrogen and phosphorus in floodwater at seven sentinel sites during 15 tidal flooding events from January 2019 to September 2020. The study area was the Lafayette River watershed in Norfolk, VA, USA, which is prone to tidal flooding and is predicted to experience more frequent and intense …

A Century Of Sediment Metal Contamination Of Mar Menor, Europe's Largest Saltwater Lagoon, Irene Alorda-Montiel, Valentí Rodellas, Ariane Arias-Ortiz, Albert Palanques, Andrea G. Bravo, Júlia Rodriguez-Puig, Aaron Alorda-Kleinglass, Carlos Green-Ruiz, Marc Diego-Feliu, Pere Masqué, Javier Gilabert, Jordi Garcia-Orellana

OES Faculty Publications

Coastal enclosed ecosystems, such as lagoons, are vulnerable to anthropogenic impacts because they favor the accumulation of contaminants from the surrounding watersheds, particularly in their sediments. Europe's largest saltwater lagoon, the Mar Menor (SE, Iberian Peninsula), is a highly impacted ecosystem and the first in the continent to be granted personhood rights. Based on a high-resolution spatial and temporal dataset, we present the historical reconstruction of metal contamination in this ecosystem during the last century. Our results highlight that sediment metal contamination has been mainly driven by the development of the mining industry in the nearby Sierra Minera de Cartagena-La …

Ensemble Machine Learning Approaches For Bathymetry Estimation In Multi-Spectral Images, Kazi A. Islam, Omar Abdul-Hassan, Hongfang Zhang, Victoria Hill, Blake Schaeffer, Richard Zimmerman, Jiang Li

OES Faculty Publications

Traditional bathymetry measures require a large number of human hours, and many bathymetry records are obsolete or missing. Automated measures of bathymetry would reduce costs and increase accessibility for research and applications. In this paper, we optimized a recent machine learning model, named CatBoostOpt, to estimate bathymetry based on high-resolution WorldView-2 (WV-2) multi-spectral optical satellite images. CatBoostOpt was demonstrated across the Florida Big Bend coastline, where the model learned correlations between in situ sound Navigation and Ranging (Sonar) bathymetry measurements and the corresponding multi-spectral reflectance values in WV-2 images to map bathymetry. We evaluated three different feature transformations as inputs …

Dynamic Stability Test Technique For Blunt Bodies In A Magnetic Suspension And Balance System, Caleb Hull, Colin Britcher, Dave E. Cox, Mark Schoenenberger, Hisham M. Shehata

Mechanical & Aerospace Engineering Faculty Publications

Techniques for the measurement of subsonic dynamic stability derivatives of blunt-body re-entry capsules are being developed using a Magnetic Suspension and Balance System at NASA Langley Research Center. The measured aerodynamics of a 45-degree sphere-cone similar to configurations being considered for Mars Sample Return Earth Entry Vehicle are reported. A novel test method has been developed where forced oscillatory translation of a test article is used to excite yaw attitude oscillations. The forced motion is then halted to observe free-to-oscillate behavior of the test article. Parameter identification methods are used to extract static and dynamic yawing moment stability characteristics from …

Polymorphism And Mechanical Behavior In Hot-Pressed 3d-Printed Polyamide Composite: Effects Of Pressure And Temperature, John Barber, Patricia Revolinsky, Jimesh Bhagatji, Diego Pedrazzoli, Sergii Kravchenko, Oleksandr Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

The aim of this work is to study the effect of high-temperature compaction (HTC) upon the polymorphism and the mechanical behavior of an additively manufactured (AM) carbon fiber-reinforced polyamide (PA6). Different pressure and temperature levels during HTC were tested to determine the overall effect on the mechanical behavior and material crystalline composition. Treated, carbon fiber-reinforced PA6 samples were analyzed using differential scanning calorimetry, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and three-point bending testing. When considered with respect to as-printed samples, an HTC temperature of 190 °C combined with 80 psi pressure resulted in an increased flexural modulus and strength …

Optimizing Material Selection And Operational Conditions For Xhv Systems: Lessons From Aisi 1020 And 316l Comparative Studies, Aiman H. Al-Allaq, Md Abdullah Mamun, Matt Poelker, Abdelmageed Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

In this study, AISI 1020 low-carbon steel was investigated as a cost-effective alternative to SS316L stainless steel for reaching extreme high vacuum (XHV) conditions. After being baked at 400°C, a vacuum chamber made of low-carbon steel material exhibited an outgassing rate approximately 2000 times smaller than a similar chamber made of stainless steel. Its activation energy for hydrogen diffusion (27 kJ/mol) is less than half that of stainless steel (60.3 kJ/mol), indicating more efficient hydrogen removal during bakeout. MolFlow+ simulations supported the experimental data and demonstrated the importance of system geometry optimization and minimizing stainless steel content for achieving optimal …

Fault Tree Analysis For Robust Design, Jonathan Degroff, Gene Jean-Win Hou

Mechanical & Aerospace Engineering Faculty Publications

The objective of this research is to incorporate system failure into a robust design formation and solution process. The system failure referred to here will be built using fault tree analysis (FTA), which will take all lower-level failure events into consideration. Two examples are investigated here. One will directly treat the probabilities of the basis events as design variables, The other will be formulated in five different models: deterministic design optimization, the reliability index-based, the “and” gate-based, the “or” gate-based and the “inhibit” gate-based robust design. Their corresponding optimization solutions will be compared with each other. The post-optimality analysis of …

Polarized Positrons At Ce⁺Baf, A. Ushakov, J. Benesch, M. Bruker, L. Cardman, J. Conway, S. Covrig Dusa, P. Degtiarenko, Y. Enomoto, S. Gessner, P. Ghoshal, S. Gopinath, J. Grames, C. Gulliford, S. Habet, G. Hays, C. Hernández-García, A. Hofler, R. Kazimi, M. Kostin, V. O. Kostroun, F. Lin, V. Lizárraga-Rubio, K. Mahler, Y. Morikawa, S. Nagaitsev, S. Ogur, G. Palacios-Serrano, N. Raut, B. Rimmer, Y. Roblin, A. Seryi, K. Smolenski, M. Stutzman, R. Suleiman, A. Sy, N. Taylor, D. Turner, A. Ushakov, C. Valerio-Lizarraga, E. Voutier, S. Wang, Y. Zhang

Mechanical & Aerospace Engineering Faculty Publications

A baseline concept for a continuous wave (CW) polarized positron injector was developed for the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab [1]. This concept is based on positron beam generation by a high current polarized electron beam (1 mA, 120 MeV, >85% polarization) irradiating a rotating water-cooled tungsten target or liquid metal target. The update on the development of the Ce⁺BAF injector concept including the polarized electron source, the development of high power targets, simulations of positron capture, the design of the transport line from the positron injector to the CEBAF North Linac and the planned experiment …

Revealing Spatiotemporal Neural Activation Patterns In Electrocorticography Recordings Of Human Speech Production By Mutual Information, Julio Kovacs, Dean Krusienski, Minu Maninder, Willy Wriggers

Mechanical & Aerospace Engineering Faculty Publications

Background

Spatiotemporal mapping of neural activity during continuous speech production has been traditionally approached using correlation coefficient (CC) analysis between cortical signals and speech recordings. A prior study employed this approach using electrocorticography (ECoG) data from participants who underwent invasive intracranial monitoring for epilepsy. However, CC cannot detect nonlinear relationships and is dominated by the correspondence between periods of silence and of non-silence.

New Method

We introduce the mutual information (MI) measure, which can capture both linear and nonlinear dependencies. We validated CC and MI on the sub-second spatiotemporal brain activity recorded during continuous speech tasks. To refine the results, …

Traction Force Microscopy Using An Epifluorescence Microscope: Experimental Considerations And Caveats, Zaria Booth, Mazen Mezher, Rudra Patel, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Forces exerted by cells due to their internal contractility play fundamental roles in a host of processes, including adhesion, migration, survival and differentiation. Traction force microscopy (TFM) enables the determination of forces exerted by cells or cell collectives on their environment, which is typically taken to be an extra-cellular matrix (ECM)-coated substrate. Sample preparation for TFM involves the plating of cells onto an environment embedded with fiducial markers. The imaging of these fiducial markers in the presence and absence of the cells then enables calculation of the displacement of localized regions of the environment, and, consequently, the spatial distribution of …

An Analytical Model Of Motion Artifacts In A Measured Arterial Pulse Signal—Part Ii: Tactile Sensors, Md Mahfuzur Rahman, Subodh Toraskar, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

This paper, the second of two parts, presents an analytical model of motion artifacts (MA) in measured pulse signals by a tactile sensor, which contains a deformable microstructure sitting on a substrate. While the tissue-contact-sensor (TCS) stack and the sensor are both treated as a 1DOF (degree-of-freedom) system, tissue–sensor contact joins their mass together to form a 1DOF system with springs and dampers on both sides. MA on the sensor substrate causes baseline drift and time-varying system parameters (TVSP) of the TCS stack simultaneously. An analytical model is developed to mathematically relate baseline drift and TVSP to a measured pulse …

Scaffolds With Spatiotemporally Controlled Growth Factor Delivery And Cyclodextrin-Enabled Antagonism Of Growth Factor Receptor Sequestration Promote Cutaneous Wound Healing, Jelena Marjanovic, Veronica Jurczuk, Lilian Valadares Tose, Yarixa Cintron Diaz, Francisco Fernandez Lima, Beatriz Abdo Abujamra, Sara Danker, Sinan Jabori, Devinder Singh, Jamie L. Burgess, Joshua Tam, Mohamadmahdi Samandari, Rivka C. Stone, Stephen C. Davis, Robert S. Kirsner, Marjana Tomic-Canic, Fotis M. Andreopoulos, Ivan Jozic

Mechanical & Aerospace Engineering Faculty Publications

Chronic wounds present a major burden to patients, health care professionals, and health care systems worldwide, yet treatment options remain limited and often ineffective. Although initially promising, growth factor-based therapies displayed limited and underwhelming effectiveness largely due to poor bioavailabilbioity and impaired receptor function within the chronic wound microenvironment. Here we demonstrate that chronic wounds exhibit elevated cholesterol synthesis, which disrupts growth factor signaling by sequestering receptors within lipid rafts. To address this, we developed a novel therapy combining growth factors with cyclodextrin in an ECM-mimetic scaffold, enabling localized cholesterol modulation and improved receptor accessibility. We demonstrate that this approach …

Mass-Adaptive Admittance Control For Robotic Manipulators, Hossein Gholampour, Jonathon E. Slightam, Logan E. Beaver

Mechanical & Aerospace Engineering Faculty Publications

Handling objects with unknown or changing masses is a common challenge in robotics, often leading to errors or instability if the control system cannot adapt in realtime. In this paper, we present a novel approach that enables a six-degrees-of-freedom robotic manipulator to reliably follow waypoints while automatically estimating and compensating for unknown payload weight. Our method integrates an admittance control framework with a mass estimator, allowing the robot to dynamically update an excitation force to compensate for the payload mass. This strategy mitigates end-effector sagging and preserves stability when handling objects of unknown weights. We experimentally validated our approach in …

Optimal Manipulation Motion Action Planner Enabled By Physics Informed Neural Networks, Jonathon E. Slightam, Logan E. Beaver

Mechanical & Aerospace Engineering Faculty Publications

Autonomous robotic manipulation in unstructured environments faces many challenges and is hindered by capabilities that bridge the gap between perception and acting on the world. Action plans that are centric to object motion rather than end-of-arm tooling behavior may aid this. This paper presents an autonomous action planner for a feedback linearizeable system comprised of three base motions that can be leveraged on their own or in combination to give custom motion plans. The optimization routine for the three different types of motion are presented, which are integrated into physics informed neural networks. A component of this is the autonomy …

Mitigating Out-Of-Plane Fiber Waviness In Afp Laminates With Tow-Gaps Via Selective Placement Of Thermoplastic Veils, Ahmadreza Ravangard, Kuthan Celebi, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Fiber tow-gaps and overlaps formed during the Automated Fiber Placement (AFP) process pose a significant challenge by introducing non-uniform composite morphologies, often characterized by resin-rich regions and fiber waviness. These defects occur as deposited fibers sink into the gap regions during consolidation, with gap geometry determined during path planning. Such morphological inconsistencies can compromise structural reliability by initiating premature failure, particularly through localized out-of-plane waviness and resin accumulation. This study investigates the integration of high melting temperature thermoplastic veils, specifically polyetherimide (PEI), into fiber tow-gaps as a method to prevent ply sinking and reduce fiber waviness on both internal and …

The Role Of Gis In Promoting The 15-Minute City Concept For Sustainable Urban Using Network Analysis (Case Study: El Rehab City), Eman Metwally, Yara Menshway, Farag Mohamed Zaki

Mansoura Engineering Journal

The 15-minute city concept emphasizes the importance of urban planning where essential services and amenities are accessible within a 15-minute walk or bike ride. Geographic Information Systems (GIS) provide powerful tools to evaluate and enhance this concept. This study applies a theoretical framework combined with quantitative methods, utilizing GIS-based network analysis to evaluate the accessibility of key services within a 15-minute walking and cycling distance. The goal is to identify critical amenities that support urban sustainability and mobility. In this case, GIS is used to model El Rehab’s Road network, pedestrian paths, and bike lanes. Network analysis techniques calculate the …

Placemaking For Revitalizing Neglected Urban Open Spaces To Act Sustainable, The Third Settlement, New Cairo, Egypt, Reham Othman El Sayed, Rania Badawy Shokry

Mansoura Engineering Journal

A key approach to creating resilient cities is to scrutinize the existing urban fabric, redesign and placemaking unused urban spaces as multi-purpose spaces capable to improve Community-Based Urban Design. The study aims to investigates highlights the importance of possibility to increasing value of existing NUOS as an essential entry point for placemaking. IN addition, it is urging considering the unused spaces as a basis for formulating an urban greening policy and strategy in Cairo. To reach that the study identifies with co-operate with the city administrative apparatus a NUOS in area is considered relatively new in Egypt, and specifically in …

High Voltage Circuit Breaker Arc Modelling State Of Art, Raghdaa I. Elbahy, Ahmed M. Abdelbaset, Ebrahim A. Badran, Mansour H. Abdel-Rahman

Mansoura Engineering Journal

High-voltage (HV) circuit breakers (CBs) are critical for safe and reliable power system operation. However, electric arcs formed during current interruption pose a challenge due to their complex, non-linear behavior. These arcs can hinder CB efficiency and cause equipment damage. To address this, understanding and modeling arc properties are essential. This paper explores existing methods for modeling and simulating electric arcs in HV CBs, including physical, black box, and parameter models. By analyzing these approaches, the paper emphasizes the importance of arc modeling for CB optimization and outlines the physical, mathematical, and software requirements for effective modeling and simulation.

Geopolymer Concrete Performance Utilising Waste Glass: A Review, Al-Saeed Abdelsalam Maaty, Mariam Farouk Ghazy, Mohamed Gamal Eldmarny

Mansoura Engineering Journal

The cement and concrete industry significantly contribute to global environmental challenges, accounting for 8% of global carbon dioxide emissions and extensive resource depletion. Geopolymer concrete has emerged as a sustainable alternative, offering up to 80% reduction in carbon dioxide emissions compared to conventional concrete by utilizing industrial by-products such as fly ash and ground granulated blastfurnace slag. Additionally, over 130 million tons of glass are produced globally each year, with 79% discarded in landfills due to issues like color inconsistencies and compositional defects. Incorporating waste glass into geopolymer concrete addresses critical waste management issues while enhancing mechanical, durability, and microstructural …

An Experimental Study On Durability Properties Of Reactive Powder Concrete Containing Silica Fume And Fly Ash As Supplementary Cementitious Materials, Ayat Mohamed Hassan Taha, Mohamed Hussain Ali Makhlouf, Khaled Mohamed El-Sayed, Gamal Ismaail Khaleel

Mansoura Engineering Journal

The paper reports the influence of using silica fume (SF) and fly ash (FA) as supplementary cementitious materials (SCMs) on the durability properties of reactive powder concrete (RPC), focusing on sorptivity, ultrasonic pulse velocity (UPV), and carbonation depth. The study additionally compares the performance of RPC with highstrength concrete (HSC) to assess the relative benefits of RPC. A total of 19 mixtures, including 17 RPC and 2 HSC mixtures, were evaluated. Parameters such as volume of binder content (45%, 50%, 55%, and 60%), water-binder ratios (20%, 25%, and 30%), and SCM proportions (0%, 10%, 20%, and 30%) were varied; these …