bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review of Geometric Modeling Design and Deployment Mechanism of Flasher-based Origami
Authors: Gu Yongxia , Hao Liang , Zhao Jieliang , Xing Wenxu , Ke Shihao , Yu Youhe , Zhang Tianyu , Zhang Chenyang
Published: January 2025

The flasher origami structure is a complex origami design characterized by multilayered coupling properties and deployment by rotational motion around an axis. This structure boasts an expansion ratio of up to 1:1000, making it highly desirable as a deployable structure in engineering applications. This review provides a comprehensive overview of the geometric modeling and deployment mechanisms of flasher origami. The current application areas of such structures are also outlined, serving as a foundational reference for future research. By reviewing the historical evolution and major research topics related to flasher origami structures, this paper categorizes related research into two main themes: theoretical research and applied research. Depending on the distinct needs of theoretical and applied research, the design methods and principles of flasher origami structures are adjusted, offering a roadmap for future studies. This paper summarizes the deployment mechanisms and existing applications of flasher origami structures and provides insights into future research directions. The goal is to stimulate innovative applications and guide future research efforts. Finally, common challenges encountered in application scenarios, simulation analysis, usage limitations, and practical implementation of flasher origami structures are addressed, and a forward-looking perspective on the research prospects in this field is offered.
A Study on Eliminating Dip in Head Curve of High Specific Speed Pumps
Authors: Ali Azfar , Jia Kun
Published: January 2025

High specific speed pumps often exhibit unstable head-characteristics at low volumetric flow rates, with a dip or positive slope in the head-curve occurring typically between 50 to 65 percent of the BEP flow rate. This results in a limited operating range for the pump. Furthermore, these pumps usually have a high rise to shut-off in terms of head and power. This study is aimed to eliminate these instabilities in the head curve and develop methods to design VCT pumps with a wider operating range of flow rates and lower shut off power without compromising efficiency.

In this study, first the existing baseline design with a dipping head curve was modeled, analyzed, and validated using the commercial CFD tool Simerics-MP+ then new designs were created while maintaining the overall dimensions of the baseline pump and simulations were performed. Simulations were conducted for the entire flow range from Shut-Off to Runout. The CFD studies revealed that many of the new designs are “dipless” with specific speeds ranging from 7000 to 8800 in US units. The pump head and efficiency were evaluated between Pit inlet and Bowl exit, and each model consisted of six components, namely Pit, Suction Bell, Impeller, Mixing Zone, Bowl, and Outlet extension. The mesh count for the models ranged from 2.3 to 4.5 million cells, and all models were transient 3D simulations with a cavitation sub-model to obtain the desired accuracy.

The paper presents findings that suggest that the instability or dip in the head curve can be attributed to one or a combination of factors such as suction recirculation, discharge recirculation, recirculation in the bowl, or excessive head loss in one or more components of the pump. The dip in the head curve represents an excessive head loss occurring at a specific flowrate. There is no singular cause for the dip in the head curve, but rather a combination of losses resulting from the aforementioned phenomena. It is important to note that the Euler’s head or Theoretical head of the impeller is always increasing with reducing flowrate, meaning it does not have any dip or instability.

In addition, our research demonstrates that the commonly accepted notion that discharge recirculation occurring on the hub side of the impeller at low flow rates is the reason for dip in head curve is incorrect for high specific speed VCT pumps. All our dipless designs show discharge recirculation occurring on the hub side of the impeller at low flow rates. In fact, the designs having dip in head curve always show discharge recirculation on the shroud side of the impeller.
A Mixed-Finite Element Method Based Formulation for the Static Bending Analysis of Eringen’s Strain-Driven Timoshenko Nanobeams
Authors: Khanra Gaurab , Krishna I. R. Praveen , P. Raveendranath
Published: January 2025

This study uses the Mixed Finite Element Method (MFEM) to analyze the static bending of nanobeams modeled according to Timoshenko beam kinematics. Formulations are suggested based on Eringen’s strain-driven, differential nonlocal constitutive model. Variously configured nanobeams are examined under point/concentrated and Uniformly Distributed Loads (UDL). The computed results of the derived quantities (bending moments, shear forces) and fundamental quantities (deflections, section-rotations) are compared with those of the conventional Finite Element Method (FEM). In comparison to FEM, the superior performance of MFEM, as demonstrated by it’s consistent ability to capture size effects regardless of the applied load type and nanobeam boundary conditions, is exhibited.
Vortical Separated Flow Over and Behind a Medium-Duty Box Truck
Authors: Molki Majid , Andrew Miracle Emaikwu
Published: January 2025

The aerodynamic performance of medium-duty box trucks significantly impacts fuel economy and environmental sustainability. However, research on their aerodynamics has been limited compared to heavier trucks. This study uses computational fluid dynamics simulations to investigate the complex flow field and its influence on lift and drag forces for a simplified box truck model. This investigation indicates rolling vortices over the roof and the wake region dominate the flow, influencing lift and drag forces. Cargo bay size influences flow over the truck. Smaller heights create an upward lift force, potentially impacting tire traction. Flatbed configurations generate a low-pressure wake, further diminishing traction. Drag coefficients compared with the literature show values fall within the established range for objects with wake regions, validating the numerical approach. This study highlights the intricate aerodynamics of medium-duty box trucks and the impact of cargo bay geometry. By optimizing shapes and reducing flow separation, we can pave the way for more fuel-efficient and environmentally friendly medium-duty trucks.
Proof of Concept For a Liquid Gyroscope
Authors: Diesen Jarle , Haugstad Kristoffer , Gjøringbø Johannes , Vea Emanuel , Impelluso Thomas , Rykkje Thorstein Ravneberg
Published: January 2025

The long-term goal of this work is to demonstrate the power of a new method in machine dynamics that engages students and inspires innovation. The short-term objective is to exploit Lorentz force effects to create a liquid gyroscope to assess orientation. This is a transdisciplinary educational project at the intersection of mechanical engineering, electrical engineering, design, and manufacturing to create the prototype. The project used Galinstan, a liquid metal alloy consisting of gallium, indium, and tin, to create the liquid metal gyroscope. When exposed to a magnetic field and an electrical current, Galinstan displays unique behavior, resulting in the formation of vortex-like patterns. This study aims to investigate the potential of utilizing this phenomenon for gyroscopic applications. This project is student conceived, initiated, and conducted based on inspiration from the Moving Frame Method (MFM) in Dynamics. The MFM is a new approach to machine dynamics that simplifies the discipline, by leveraging Lie Group Theory and Algebra (distilled to the simplicity of matrices), Cartan’s sense of moving reference frames and a compact notation. First, this paper briefly summarizes the MFM and how it stimulates student learning in an era of disengagement. Then this paper launches into a description of the concept, design, and construction of the liquid gyroscope. This paper discusses the difficulties of achieving precise control, stability, and practicality such as turbulence in the liquid corrosion and magnitude of the magnets. The project recognizes the need to understand fluid dynamics, chemistry mechanics, as well as electro mechanics to overcome these challenges and advance the concept of a liquid metal gyroscope. This current investigation is exploratory and provides insight into the potential applications and practical experience within the field.
Analysis of an Offshore Personnel Transfer System
Authors: Rykkje Thorstein R. , Hamrah Suliman , Myklebost Sondre , Impelluso Thomas
Published: January 2025

Offshore Personnel Transfer Systems (OPTS) facilitate safe and efficient personnel transfer between offshore installations and marine vessels. These systems integrate state-of-the-art engineering principles and advanced materials to ensure reliability and optimal performance in formidable conditions. Through intricate movements and precise positioning, OPTS enable optimal access during personnel transfer operations and prove indispensable in navigating unpredictable weather conditions. While material considerations play a role in their design, this paper focuses on the dynamic design strategies employed in the construction of OPTS. Within this study, the Moving Frame Method (MFM) emerges as an optimal framework for analysis. Rooted in the foundational principles of Lie Group Theory and Cartan’s notion of moving reference frames, the MFM provides an efficient means of analyzing single and multi-body dynamics. By harnessing the capabilities of the Special Euclidean Group for analysis and simulation, this paper illustrates how the MFM serves as a catalyst for advanced research. Furthermore, recent extensions, notably the development of a kinematic transfer variable, improve the algorithm for the MFM. Complementing this analytical approach, the integration of WebGL for 3D simulations offers a visually immersive experience, fostering a comprehensive understanding of system behavior and performance dynamics. This project (revisiting legacy software with modern mathematics) serves as a pivotal step towards the seamless integration of smart technologies within OPTS. Through the incorporation of real-time monitoring, sensor feedback, automated control systems, and a real-time physics model, the next phase of OPTS promises unparalleled levels of operational efficiency and safety by the creation of a digital twin.
A Computational Fluid Dynamics Model for Investigation of Material Flow in a Perfusion Bioreactor Toward Optimal Biomedical Design of Cell-Laden Scaffolds for Bone Regeneration
Authors: Rollins Hannah , Salary Roozbeh “Ross”
Published: January 2025

In tissue engineering, once a scaffold has completed mechanical property testing, it must then undergo biological characterization which determines if the scaffold is capable of supporting cell viability. To perform biological tests, cells must be seeded onto a scaffold with the help of bioreactors, the four main types being: (i) rotating wall, (ii) spinner flask, (iii) compression, and (iv) perfusion bioreactor. In perfusion bioreactors, a consistent flow of material is introduced (using a pump) into the inlet of the bioreactor chamber where multiple scaffolds of a disc geometry are located. However, the intrinsic, complex interaction between the scaffolds and material flow as it goes through the bioreactor chamber affects the viability of the seeded stem cells. Therefore, there is a need to identify consequential fluid dynamics phenomena governing the material flow in a perfusion bioreactor.

In this study, using a CFD model, the effects of critical scaffold parameters (such as the number of scaffolds, scaffold diameter, scaffold thickness, and number of pores) on the main flow properties (i.e., flow pressure, wall shear stress, and streamline velocity) influential in cell proliferation and bone development will be investigated. It was observed that increasing the number of pores, in addition to decreasing the pore diameter had an adverse effect on the maximum forces occurring on the scaffold. In addition, changing the overall scaffold diameter did not appear to have as much as an effect as the other parameters. Furthermore, it was observed that a decrease in porosity would lead to an increase in wall shear stress and consequently in cell death. Overall, the outcomes of this study pave the way for optimal design, fabrication, and preparation of cell-laden bone scaffolds for treatment of bone fractures in clinical settings.
Mounting System Nonlinearities in Planar Dynamics of Motorcycles: An Analytical Study
Authors: Kaul Sudhir
Published: January 2025

Engine mounting systems are not commonly used in motorcycle powertrains. However, some motorcycle manufacturers design engine mounting systems to mitigate shaking forces, or to isolate the frame from torque recoil, or to enhance vibration isolation at idling. Most of the passive engine mounting systems are inherently nonlinear due to material properties, damping, design parameters, etc. This paper examines the influence of some of the nonlinearities of an engine mounting system on the planar (in-plane) dynamics of a motorcycle. While the primary aim of an engine mounting system is to enhance ride comfort, some of the nonlinearities associated with the system can influence handling in a motorcycle due to the coupled dynamics of the rear unsprung mass and the swing arm. The specific nonlinearities investigated in this study are limited to stiffness and damping characteristics of the engine mounting system, and the statistical linearization method has been used to derive the corresponding equivalent linear models. The equivalent linear models are seen to successfully represent nonlinearities such as varying levels of progressive increase in effective stiffness and different forms of damping such as quadratic damping of the mounting system. For analytical purposes, road surface irregularity is used as the main excitation input while the motorcycle is traveling in a straight line at a constant velocity. Acceleration spectrum of the sprung mass is seen to be directly influenced by varying levels of stiffness and damping nonlinearities of the engine mounting system while the spectrum of the two unsprung masses does not exhibit any significant influence. Overall, it is observed that the nonlinear models provide an analytical insight that can be useful during the early stages of development of the mounting system of a motorcycle while making critical design decisions. Even though the nonlinearities investigated in this study are limited to stiffness and damping characteristics of the mounting system, the models presented in the paper can also be used to examine other nonlinearities that may be critical for the analysis of planar dynamics.
Inclusion of Manufacturability Considerations on Design Optimization of a Composite Rotor Blade
Authors: Wall Emily S. , Haehnel Robert B. , Sharma Gehendra S. , Dalton Larry , McCall Tonya G. , Dettwiller Ian , Huberty Wayne
Published: January 2025

The optimization of rotor blade aerodynamic and structural design is pivotal for enhancing overall rotorcraft performance in terms of, e.g., reduced power requirements and energy consumption, and increased range and cargo capacity. Use of composite blades are increasing attractive owing to improved fatigue characteristic, reparability, etc., however, not all proposed composite structure designs are practical to manufacture. This research effort explores the intricate relationship between composite blade design and manufacturability, the potential utility of optimization software (e.g., iVABS) to improve the overall manufacturability of a given structural design. Integrated VABS (iVABS) is a software tool developed to aid in the design optimization of composite slender structures. Design parameters can be defined in iVABS to control various aspects of the internal structure such as spar web spacing, web curvature, number of plies, fiber orientation, and materials, many of which have a direct effect on the overall manufacturability of the blade. The team delves into the critical aspects of manufacturability that directly influence the manufacturing process. The overarching goal is to establish rules that will guide a manufacturability assessment that can be integrated into the initial design phase, guiding iVABS towards creating rotor blade designs that not only meet stress, strain and aerodynamic requirements, but are also inherently more manufacturable. The integration of manufacturability considerations into the optimization process, as demonstrated by these efforts, represents a proactive approach to ensuring that optimal structural designs align with the capabilities and constraints of the given manufacturability processes, thereby streamlining the manufacturing process. The research includes the consideration of the manufacturability constraints that could be applied to the identified design parameters and demonstrates how this can be applied via a case study showing both the iVABS design results and the manufacturability score — produced by an expert system designed from the rules — for both designs. This work proposes a foundation for a more holistic approach to rotor blade development, where design optimization tools, like iVABS, can be used by experienced engineers to reduce design cycle times, foster innovative, and yield manufacturable designs. The findings presented here show the importance of considering manufacturability alongside structural optimization for more efficient and practical rotor blade development.
Optimizing Control Systems: A Comparative Analysis of 77 Multi-Objective Evolutionary Algorithms
Authors: AbuKwaik Mohammad , Sardahi Yousef , Alshorman Ahmad M.
Published: January 2025

Multi-objective optimization is integral to control systems, particularly in engineering, where multiple objectives must be concurrently satisfied. This study pioneers a comprehensive comparison of 77 evolutionary algorithms for optimizing a second-order system under a proportional-integral-derivative (PID) controller. We emphasize the challenges of balancing conflicting metrics like peak time and percentage overshoot and how PID controller tuning is crucial in achieving this balance. To assess the algorithms’ performance, we utilize four different performance metrics, which encompass Generational Distance (GD), Spacing, Spread, and computation time. The optimization results are analyzed using two methods. Firstly, after 1 million iterations, outcomes are visually represented through discrete charts for each algorithm, detailing their performance metrics. The Multiple single objective Pareto sampling II (MSOPSII) algorithm demonstrates the most effective distribution of the solution set and maintains uniformity well. The Indicator-Based Evolutionary Algorithm (IBEA) excels in the Spacing Metric, while the Speed-constrained Multi-objective Particle Swarm Optimization (SMPSO) algorithm exhibits superior convergence. Secondly, algorithms with optimal performance are evaluated by considering multiple metrics simultaneously. The theta-Dominance-based Evolutionary Algorithm (tDEA) leads in combined convergence and spread, Multi-Tasking Constrained Multi-objective Optimization (MTCMO) stands out for convergence and spacing, and MSOPSII and IBEA perform best in spread and spacing. Across all three metrics, MOEA/D with Adaptive Weight Adjustment (MOEADAWA) emerges as the top performer. These outcomes not only advance our understanding of algorithmic efficiency in multi-objective scenarios but also provide valuable insights for the application of these algorithms in practical control system challenges. This research fills a critical gap in existing literature, offering an in-depth evaluation of a wide range of algorithms in the context of control systems.
Design Space of a Tactical, Air-Launched Balloon
Authors: Bellocchio Andrew , Brininger Adler , Phillips Garrett , Sharp David , Sheridan Magnus
Published: January 2025

Small, air-launched balloons may be rapidly deployed from aircraft to deliver payloads over inaccessible areas. These balloons are economical and attritable, providing an alternative to today’s drones, satellites, and crewed aircraft. This effort explored the conceptual design of air-launched balloons from a Chinook helicopter. Upon air drop and opening of a parachute, helium inflates the balloon. After inflation, the balloon and payload detach from the parachute to ascend to an operating altitude. A zero-pressure balloon vented to the atmosphere maintains neutral buoyancy at the target altitude for several days. Feasibility was evaluated by investigating inflation time against descent time. A non-linear differential equation of motion and its numerical solution created a flight profile for payloads between 5–30 kg to demonstrate feasibility. Models for helium’s inflation rate of isentropic, chocked flow and buoyancy force were experimentally validated and incorporated. Available time of descent from 10,000 feet was between 650 to 770 seconds with system mass between 246 to 370 kg and a balloon radius of 2.7 to 3.7 meters. The air-launch concept was proven feasible; however, a few technical challenges were discovered such as managing the inflation force to prevent balloon tearing, separating the balloon from the parachute, and packing.
Passive Ankle-Foot Orthoses: A Novel Approach for Passive Support of Plantar and Dorsiflexion Based on an Innovative Mechanism and Closed-Loop Logic
Authors: Steck Patrick , Scherb David , Miehling Jörg , Wartzack Sandro
Published: January 2025

The shifting demographics worldwide signal a looming challenge: an increasingly aging population. Along with this demographic shift comes an increase in age-related health issues, with neurological conditions like strokes being especially prominent. Patients who suffering on such diseases often have a so-called plantar and dorsal weakness, i.e. a reduction in lifting and lowering the foot during gait. An established treatment method is the use of so-called ankle foot orthoses (AFO). While active AFOs offer dynamic support through external energy sources, passive AFOs are more reliable because of the use of their inherent stiffness and the energy provided by the wearer itself. Despite their potential benefits, current passive AFOs predominantly focus on supporting dorsiflexion. Research into the passively support of plantar flexion is still at the beginning and is now to be significantly expanded by the innovative mechanism presented in this article. The mechanism uses torsion springs that harvest energy during specific gait phases and release it when it comes to a trigger moment during the gait cycles. This energy harvesting and supplying were simulatively tested with multi body simulation. The simulations of the mechanism showed support of the ankle moment by 58% (79 Nm) for a test subject with 50% muscle weakening (50 N m) and an average gait speed of 1.4 m s−1.
Assessment of Sense of Belonging and Systems Thinking Skills In Introduction to Mechanical Engineering Courses at Three Academic Institutions
Authors: Muci-Küchler Karim , Pottmeyer Laura , Bedillion Mark , Birrenkott Cassandra , Melville Michael
Published: January 2025

Many mechanical engineering undergraduate programs include a freshman-level introduction to mechanical engineering course that introduces students to the mechanical engineering profession and helps them start developing basic skills such as working with science and engineering units and solving technical problems following a systematic approach. In addition, some programs include additional topics that they feel are of particular importance. To that end, the mechanical engineering undergraduate programs at three universities decided to incorporate basic systems thinking and systems engineering concepts into their introduction to mechanical engineering course. To assess the impact of the introduction to mechanical engineering course on student’s sense of belonging in mechanical engineering and on their perceived self-efficacy in systems thinking skills, a survey was applied as a pre- and post-assessment during two consecutive semesters in all the sections of the course at the three universities. This paper provides general information about the introduction to mechanical engineering course at each of the three universities, the common instructional materials used at the three universities to teach systems thinking and systems engineering concepts, and the survey instrument used. Finally, the survey results and the corresponding analysis are presented demonstrating the student improvement in both their self-efficacy with systems thinking skills and their sense of belonging in mechanical engineering.
Monitoring Mining Dump Truck Operations Using Convolutional Neural Networks
Authors: Dewangan Nagesh , Mohanty Amiya Ranjan
Published: January 2025

Mining dump trucks are heavy-duty equipment often used for tasks such as material transportation. Coal production at mining sites relies heavily on the effective utilization of dump trucks, specifically designed to carry out a range of tasks crucial for the mining industry. Therefore, monitoring dump truck operations plays an important role in maximizing the overall production of any coal mine. Moreover, the complexity of operations performed by dump trucks necessitates effective monitoring and detection using suitable tools. This study focuses on enhancing monitoring tasks by leveraging image classification algorithms specifically trained to identify operations related to dump trucks. A deep learning-based monitoring approach was developed for monitoring areas, such as identifying transportation-related operations in open-cast coal mines carried out by dump trucks. The study employed vibration signal and its Power Spectral Density images classification to identify dump truck operations. Various established architectures of Convolutional Neural Network were implemented in the approach, and their performances were systematically evaluated. The study has investigated AlexNet, DenseNet121, EfficientNetV2, InceptionResNetV2, ResNet50, and Xception for dump truck operation monitoring. Moreover, the study explored the effectiveness of the models through a case study of vibration measurements from two dump trucks.
A New Planar Overconstrained Mechanism Generated by Merging Two Symmetric Watt’s Six-Bar Linkages That Perform Gear-Like Motion
Authors: Chan Cody Leeheng
Published: January 2025

This paper explores the synthesis of a planar overconstrained mechanism potentially for a folding hinge application. Inspired by a folding hinge patent from a phone company, the author analyzes the linkage and discovers a special mechanism generated by merging two symmetric Watt’s six-bar linkages. The synthesis method involves finding a Watt’s six-bar linkage with gear-like input-output motion. The differential evolution optimization algorithm is used to determine the dimensions of the linkage that satisfy the synchronized motion. Numerical results demonstrate the successful synthesis of the overconstrained mechanism with extremely low error, validating its performance. The CAD model and prototyping further confirm its functionality. This paper makes three significant contributions: Firstly, it synthesizes a Watt’s six-bar linkage that performs approximate gear-like motion for the first time. Secondly, it introduces a novel planar overconstrained mechanism and presents a methodology for its synthesis. Lastly, it proposes a potential design for synthesizing and implementing overconstrained mechanisms in foldable phone hinges, meeting requirements for compactness and durability.
Automotive Seat Back Strength Testing of 19 Front Seats
Authors: Leiss Peter , Roche Christopher , Mazza Marcus , Hoover Roland
Published: January 2025

Automotive front seat back strength in rearward loading has been researched and reported on for over fifty years. In rear impacts, the seat back provides the primary means of restraint to the occupant as the force of the collision causes the occupant to move rearward, away from their seatbelt webbing. Seat strength requirements for vehicles Certified to be sold in the United States are prescribed in Federal Motor Vehicle Safety Standard (FMVSS) 207. If the seat belt is attached to the seat frame, commonly referred to as an All Belts to Seat (ABTS) design, the seat must also meet the seat belt anchorage requirements of FMVSS 210. The strength requirements of automotive seats have remained unchanged for several decades.

This paper describes the fabrication of a wooden body block, first designed and used in static seat back strength testing in the 1960’s, and a hydraulically actuated testing rig with instrumentation recording synchronized force and displacement measurements. A six-seat repeatability study was undertaken where six seats of the same design were tested and the force versus displacement curves were analyzed for consistency prior to testing 19 different seat designs. Results of the current testing are added to previously reported seat back strength test results to identify trends in automotive seat back strength.

The 19 seats tested were selected in groups by their parent vehicle sales classification. Seventeen seats from vehicles sold in the United States D segment (mid-size) sedan, luxury sedan, and pickup-truck classifications were identified, seats procured, and tested. Also tested were seats installed in two different models of vehicles built by the same vehicle manufacturer, one was designed and manufactured by a long-standing Tier One automotive supplier of seats and interior trim components, the other was designed and manufactured in-house by the Original Equipment Manufacturer (OEM). One of the tested seat frames has features in the seat back bracket that are designed to control the deflection in rear impacts. The design of this feature changed during the production run of the seat frame design. Seats with the original and modified bracket features were tested. Maximum force and the force versus deflection curves are compared between the Tier One and OEM designed seats and the original and modified seat back brackets.

The results of this study show the test fixture produced repeatable results. The study adds to the available seat back strength test results reported in previous literature; adding these results to previous testing shows how seat back strength has changed throughout the past 60 years.
Predictive Modelling of Microfluidic Devices Targeting Cancer Cell Separation
Authors: Sarowar Md. Tanbir , Mobarrat Mahir , Chen Xiaolin
Published: January 2025

In this study, we present a comprehensive analysis of particle trajectory prediction in a Deterministic Lateral Displacement (DLD) device using both numerical simulations and machine learning models. First, we validate the accuracy of the numerical model by comparing simulation results with experimental data from previous studies. Subsequently, utilizing the validated simulation model, we generated a large dataset spanning a crucial design parameter of the DLD device, row shift fraction (ranging from 0.001 to 0.3), and different particle sizes (ranging from 6μm to 20μm). These datasets, comprising thousands of data points, serve as input for training multiple machine learning algorithms to predict particle migration trajectories within the device. Our analysis focuses on accurately predicting the two distinct modes of cell migration: bumped and zigzag. We find that the Gradient Boosting Regression Model and Random Forest Regression Model demonstrate promising capabilities in predicting the zigzag mode. Finally, applying machine learning algorithms to predict cancer cell separation capabilities, we showed that the models successfully differentiate between modes of migration for various cell types, including A549 lung cancer CTCs and white blood cells. Our findings highlight the potential of machine learning in facilitating the design and optimization of DLD devices for efficient cancer cell separation techniques.
Comparison of Shear Stress Response on Immortalized Cells to Primary Cells in Stent Analysis
Authors: Saifurrahman Hanif , Wang Zi , Jin Kazuyoshi , Ohtsu Naofumi , Ohta Makoto
Published: January 2025

Several studies have proposed methods to promote endothelization on a stent by modifying its surface. To assess the effects of such modification, in vitro analyses have been conducted with the addition of flow; however, they were constrained by duration. This problem may be solved by changing the type of cells used from primary cells to immortalized cells; however, there are no reports that confirm the feasibility of immortalized cells under flow. In this study, we examined the feasibility of this process by comparing their shear stress response with that of the primary cells. We used human carotid artery endothelial cells (HCtAEC) for primary cells and human umbilical vein endothelial cell-SV40 (HUVEC-SV40) for immortalized cells. Both cells were placed into a static and flow environment with stent struts implanted. The differences in morphology were compared. The results indicate that immortalized cells behave similarly to primary cells with respect to shear stress. They underwent elongation after exposure to shear stress and their orientation was directed parallel to the flow. They also exhibited migration tendencies in a stent-implanted environment. Although their response is impeded, they are shown to have longer survival period. Therefore, the results suggest that immortalized cells may be utilized in place of primary cells to extend the duration of stent analysis.
Impact of UV Curing on Process Variability for Impact-Resistant SLA 3D Printed Parts
Authors: Schmitz Anne
Published: January 2025

This study investigates the influence of curing parameters (temperature and time) and specimen orientation within the curing chamber on the impact resistance of stereolithography (SLA)-printed parts. The results demonstrate that curing parameters can significantly impact process consistency (Cpk) but may not have a statistically significant effect on the average impact resistance itself under the conditions explored (45°C–75°C for temperature and 15–45 minutes for time). This suggests that within this range, sufficient energy might be provided for complete resin conversion regardless of the specific temperature or time combination. Additionally, the study reveals that changing the specimen orientation from horizontal to vertical during curing can improve process consistency for a specific curing condition (60°C and 30 minutes) without affecting the average impact resistance. This is likely due to improved exposure of the resin to UV light throughout the entire specimen volume when oriented vertically. These findings highlight the importance of considering both average impact resistance and process consistency when optimizing curing parameters for SLA-printed parts. They suggest that specimen orientation can be a factor influencing process consistency for certain curing settings, potentially informing strategies to achieve consistent and reliable mechanical properties in SLA-printed parts.
Modeling of Multilayer Laminated Glass Panels Under Blast
Authors: Elkilani Ahmed , Salim Hani , Elemam Hesham , Elbelbisi Ahmed , Elsisi Alaa , Bowman Andrew , Johnson Carol
Published: January 2025

Laminated glass (LG) is widely used in building envelopes to enhance safety and mitigate hazards during blast events. This paper investigates the multilayer LG systems subjected to blast loading by means of an experimentally validated numerical simulation using ANSYS. The influence of various glass and polymeric interlayer types on the dynamic response is studied. Annealed, heat-strengthened, and tempered glass were evaluated combined with different interlayer materials. The research investigates the impact of different interlayer thicknesses of multilayer LG panels on their dynamic behavior under blast loading. The paper will highlight the importance of the glass and polymeric interlayer types on the blast performance of the LG panel. In addition, the paper will demonstrate the effect of multilayer systems and configurations on enhancing the blast resistance of LG systems compared to double-layer panels.
Heat Transfer Deterioration Mitigation for Supercritical CO2 Fluid in Inclined Mini Tubes: Computational Analysis
Authors: Elsayed Mohamed L. , Afifi Ahmed , Park Chanwoo , Mitsingas Constandinos , Kweon Chol-Bum
Published: January 2025

In this work, a comprehensive numerical simulation is conducted to investigate the heat transfer enhancement (HTE) and heat transfer deterioration (HTD) for supercritical carbon dioxide (sCO2) near the critical point in horizontal and inclined mini tubes. First, the model’s results were validated against available experimental data in the literature with good agreement. Notably, the simulations successfully capture the phenomenon of HTD at elevated heat flux to mass flux ratios. Furthermore, to highlight the advantages of utilizing sCO2, a comparative analysis with water under identical conditions is conducted. It was found that sCO2 demonstrates distinct advantages, particularly near the pseudocritical point at low heat flux to mass flux ratios. Then, the effect of different operational and geometrical parameters of circular tubes on heat transfer performance is considered. The operational parameters include mass flux, heat flux, inlet temperature, and inlet pressure. The geometrical parameters are considered to mitigate the HTD and include tube diameter, and tube inclination angle. The effects of geometrical parameters on buoyancy flow under a wide range of heat and mass fluxes are explored. The results demonstrate that the maximum heat transfer coefficient decreases significantly with the deviation of the operating pressure from the critical pressure HTE case. Additionally, the thermal performance improves significantly with the tube diameter reduction, while inclination angle has a minimal effect except for upward flow in HTD case. Finally, the results unveil that miniaturization weakens buoyancy effect.
Validation of Gelatin Layering for Ultrasound Power Transfer and Backscatter Communication
Authors: McGillivray-Seaton Kaleb , Munro Deborah
Published: January 2025

The human body is a complex system with many functions, and researchers are designing sensors to be placed within the body to monitor these functions in real-time with minimal invasiveness by using wireless power and communication methods. Ultrasound is a promising new method for wireless sensors, as it has low signal attenuation in tissue and can deliver more power for the same sized device. When testing ultrasonic devices, an alternative to human tissue is typically used, and common substitutes include animal tissue, castor oil, or water. The drawback of using animal tissue is that its properties change with time due to drying and decay. Water and castor oil properties are similar to average tissue layer properties, but not the individual layers. Although they have predictable and reliable properties, they do not mimic complex tissue anatomy well, and as they are homogenous, the reflections and refractions of ultrasound that occur in real life between tissue types do not occur. New gelatin products have emerged as promising materials for in vitro ultrasonic testing, because their properties can be chosen to mimic specific tissue layers with appropriate thicknesses. The purpose of this study was to validate techniques for the layering of gelatins, that mimic human tissue, for creating easily variable and repeatable heterogenous benchtop materials. This study used Humimic Medical Gelatin #0, a gelatin that mimics the properties of human fat. The slabs were 125 × 125 mm with thicknesses of 10, 20, and 50 mm. The ultrasound transducers were 1 MHz lead zirconate titanate discs, and a signal generator was used to drive them. Voltages across the transmission transducer and “implanted” transducer were recorded with and without water and with acoustic gel used as coupling agents between the slabs. Results demonstrated that gelatin can be a suitable material for ultrasonic device testing but must be used in conjunction with water, as a coupling agent, on the transducer-gelatin boundary to get accurate and repeatable results between test setups.
Annual Energy Estimate of Asymmetric Light Transmitting Interface Luminescent Solar Concentrators
Authors: Arnow Hannah , Logan Noah , Oliveto Vincent , Smith Duncan , Hughes Michael , Borca-Tasciuc Diana-Andra
Published: January 2025

The demand for on-site solar energy harvesting has increased over the years and is expected to surge due to more states and countries pursuing 100% clean energy. Building Integrated Photovoltaics (BIPVs) equipped with Luminescent Solar Concentrators (LSCs) are explored as a way to harvest solar energy on vertical walls. However, a main drawback is their low optical efficiency due to escape cone losses. To increase the optical efficiency of the LSCs, Asymmetric Light Transmitting (ALT) interfaces have been proposed as a way to prevent light at normal incidence from escaping through the light-receiving surface. Previous studies have simulated the optical effcieincy of LSC instrumented with an ALT interface with trapezoidal pyramid nanostructures without a complete analysis of their impact on annual energy production. The goal of this paper is to investigate the annual energy production of an LSC instrumented with ALT consisting of trapezoidal nanostructures for two specific locations: Albany, NY, and Phoenix, AZ. This estimation is carried out for a vertical and optimum angle installation. Transmission data along with direction of propagation data were collected from COMSOL to model light propagation across the ALT nanostructured interface. This data was then incorporated into an in-house Monte Carlo (MC) ray tracing code to simulate light concentration within an LSC. The MC code provided optical efficiency and spectral mismatch factor as the outputs. This data was then used in a subsequent in-house energy estimate code to determine the annual energy production of the system. The ALT interface LSC showed minimal improvements in energy production at a vertical orientation, specifically during the months of November to January with a maximum improvement of 32.2% in December in Albany, NY. The results suggest that this specific geometry of ALT nanostructures performs optimally at a vertical orientation in locations with low polar incidence and azimuth angles. Further analysis must be done to determine a geometry that improves the performance of the LSC at higher incident angles.
Integrating Computerized Tools and Hands-On Experience Into Six Sigma Curricula for Engineering Education
Authors: Chen Ruimin , Motaref Sarira
Published: January 2025

To maintain competitiveness in a manufacturing market driven by customization, the next generation of engineers must master quality assurance methodologies along with computational skills essential for continuous process improvement. Recently, students from Mechanical Engineering (ME) and Management and Engineering for Manufacturing (MEM) at a large public university have demonstrated an increased interest in acquiring Six Sigma knowledge prior to joining the workforce. This paper presents a redesign of a Six Sigma curriculum that integrates not only Minitab applications but Python programming, a step beyond conventional teaching methods, to equip students with the programming expertise required for today’s data-driven decision-making processes. Additionally, a novel course project merging Six Sigma methodologies with the additive manufacturing process has been introduced to provide hands-on experience and foster a deeper understanding of the integration of emerging technologies, the Design, Measure, Analyze, Improve, Control (DMAIC) model, and computer programming capabilities in real-world scenarios. A survey was conducted to collect feedback from students in a combined section of ME and MEM to assess their improvement in Six Sigma proficiency and computational skills. The differences in survey responses and course grades between ME and MEM students were statistically analyzed and discussed. In summary, this paper reveals the impact of curricular innovation on students’ academic performance and self-reported competencies, providing insights into the integration of traditional teaching strategies with modern computational skills.
Topology Optimization Case Study: Laser Powder Bed Fusion Material Losses, Energy Use, and Consumables
Authors: Puttonen Tuomas , Ning Shunyang , Björkstrand Roy , Salmi Mika
Published: January 2025

Additive manufacturing (AM), more familiarly known as 3D printing, has also been postulated as an advantageous manufacturing technology from a sustainability perspective. A few of these technologies, such as laser powder bed fusion (PBF-LB), have been increasingly used in industrial production. Considerable performance and efficiency increases are attainable by leveraging the increased design freedom and geometrical complexity enabled by the layer-by-layer principle of AM. Design tools, such as topology optimization, can significantly reduce part weight and yield sustainability benefits.

In the current literature, however, sustainability assessments of AM are often based on naive or overly optimistic material use ratios (raw material use : final component) which can bias the results. For example, the PBF-LB process losses to machine filters and as residuals are generally omitted.

The paper investigates the laser powder bed fusion (PBF-LB) process material efficiency through an industrial case product redesigned for AM. In this work, topology optimization is used to minimize component weight, and the part is manufactured with PBF-LB. The process energy, raw materials, consumables, and waste streams are measured for successive process steps. The result provides a new datapoint in the quest to promote a more realistic material use ratio for AM including all PBF-LB process losses.
Utilization of Additive Manufacturing for Batch Production Injection Mold Inserts
Authors: Alsayyed Basel , Patterson Cameron J.
Published: January 2025

A potential drawback of polymer injection molding is the relatively high cost of metal mold inserts. This limits a manufacturer’s ability to capitalize on smaller customized product batches and in-house cavity prototyping. To overcome this, manufacturers have found success in the use of polymer-based 3D printed molds. Professional grade stereolithography ultraviolet (SLA UV) resins have become standard materials for 3D printed molds, but there is little documentation concerning the use of other commercially available polymers. This includes materials used in inexpensive Fused Deposition Modeling (FDM) and SLA printers. The research presented in this paper explores this aspect of additive mold technology. Mold inserts composed of polylactic acid (PLA), polyethylene terephthalate glycol (PETG), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), nylon, carbon fiber polylactic acid (CF PLA) and 405 nm photopolymer resin were compared with various physical metrics. By tracking the dimensional accuracy and flash sizes over the course of 50 mold shots, the rates of cavity degradation for each insert were compared. The results of this study concluded that the most sustainable polymer mold cavity is composed of ABS or a Carbon Fiber reinforced polymer. This is followed by PC, PETG, resin, nylon, and PLA.