bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Nanomechanical Properties and Interphase of Variable-Size Hard Particles in a Soft Matrix in Atomic Force Microscopy and Finite Element Analysis
Authors: Norkus Tyler , Yekani Fard Masoud 
Published: February 2024

Abstract
Hard particles suspended in a soft matrix significantly change the properties of the surrounding matrix via interactions with matrix and through the interphase that surrounds the particles, and atomic force microscopy (AFM) is one of the techniques that has been used to characterize the nanoscale properties of such composites. AFM performed on particle-matrix composites results in complicated force-displacement data, and significant effort must be made to analyze that data. Finite element analysis (FEA) will be used in conjunction with experimental data to deconvolute and analyze the complex interactions between the AFM probe and particle-matrix composite. Previous work has been done to characterize both filled rubbers and biomaterials — which can be modeled with simpler particle-matrix composites — but the scenarios that were considered did not portray the full extent of the AFM probe’s interactions with the hard particles or matrix. A neo-Hookean constitutive material relation is assigned to the soft matrix, and the Derjaguin-Muller-Toropov (DMT) and Johnson-Kendall-Roberts (JKR) contact mechanic models are considered during analysis of the probe-particle interactions. Data from AFM performed on hard carbon nanotube (CNT) particles embedded in thermoset epoxy resin will be collected to supplement and verify FEA. Simulated force-displacement and stress field data are analyzed to extract nanoscale mechanical properties and identify the key impacts different geometries have on collected AFM data.
On the Development and Evaluation of an Affordable Telerobotic System for Object Grasping for Human-Machine Interaction
Authors: Abdul Rahaman Abdul Hafiz , Hazra Sudip , Shiakolas Panos S. 
Published: February 2024

Abstract
Due to mobility impairment, a person might rely on wheelchairs, canes, and crutches for assistance but could face challenges when performing tasks such as grasping and manipulating objects due to limitations in reach and capability. To overcome these challenges, a multi-degree-of-freedom robotic arm with an anthropomorphic robotic hand (ARH) could be used. In this research, we propose an architecture and then implement it towards the development of an assistive system to assist a person with object grasping. The architecture interlinks three functional modules to provide three operation modes to calibrate the system, train a user on how to execute a grasp, synthesize grasps, and execute a grasp. The developed system consists of a user input and feedback glove capable of capturing user inputs and providing grasp-related vibrotactile feedback, a CoppeliaSim-based virtual environment emulating the motions of the ARH, and an underactuated ARH capable of executing grasps while sensing grasp contact locations. The operation of the developed system is evaluated to determine the ability of a person to operate it and perform a grasp using two control methods; using a synthesized grasp or under real-time continuous control. The successful evaluation validates the architecture and the developed system to provide the ability to perform a grasp. The results of the evaluation provide confidence in expanding the system capabilities and use it to develop a database of grasp trajectories of objects with different geometries.
Analysis of Contact Positions of Inspection Tool for Motorcycle Safety Verification
Authors: Inui Masatomo , Umezu Nobuyuki 
Published: February 2024

Abstract
We propose a method for automatically detecting shapes that may be dangerous to pedestrians in the event of a collision using a motorcycle’s CAD model for its safety verification. A columnar inspection tool comprising a conical surface and cylindrical surface with a diameter of 300 mm, imitating an upright person, was prepared for this verification. The shape of the contact of the motorcycle with inspection tool is recognized as a shape that can cause severe injury to a pedestrian in a collision, which is modified at the designer’s discretion. The proposed technique detects the location of the inspection tool in contact with the motorcycle. It then detects the surface portions of the motorcycle that establish contact with the tool placed at that location. The former process involves slicing the CAD model of the motorcycle into several horizontal planes placed at small intervals, expanding the resulting cross-sectional figures by the radius of the inspection tool, overlapping the expanded figures, and calculating their Boolean union shape. To accelerate these processes, we developed an algorithm that leverages the parallel processing capabilities of a graphics processing unit. Computational experiments confirm the effectiveness of the proposed method.
Comparison of IZOD Impact Energies and Ductile to Brittle Transition Behavior of 3D Printed vs. Sheet Extruded Polymers
Authors: Coates Cameron , Adams Aaron , Johnson Wayne , Foster Ryan , Cook Christian 
Published: February 2024

Abstract
This work investigates the difference in impact response of sheet extruded vs 3D printed Polyethylene Terephthalate Glycol (PETG) and High Impact Polystyrene (HIPS). The effect of a machined notch vs a 3D printed notch, the effect of the raster angle, and the role of percentage infill are also examined. IZOD impact energies at temperatures ranging from −50°C to 50°C in 5°C intervals are experimentally obtained for 3D printed and extruded specimens. 3D printed specimens tested had 25% infill, 100% infill, 60° raster angle, 90° raster angle with machined and 3D printed notches.
For a 90°-raster angle, increasing infill percentage from 25% to 100% may increase the impact strength of 3D printed PETG and HIPS by 20% and 42% respectively. These gains do not seem to occur for a 60°-raster angle, neither were these gains consistent for machined notched specimens. 3D printing PETG or HIPS will generally result in materials whose DBT regions will have slopes up to 70% gentler than their sheet extruded counterparts. An increase in raster angle from 60° to 90° may reduce the DBT slope by up to 60% for either material. If an adjustment of the DBT slope is sought by altering the infill percentage for these 3D printed materials, careful attention must be paid to the raster angle used.
Phased Array Ultrasonic Nondestructive Testing for Mechanical Integrity Assessment of Steel Welding
Authors: Williams Caleb , Taheri Mohammad , Taheri Hossein 
Published: February 2024

Abstract
Variety of structures and components are using welding processes as the major method of joining. Various materials such as steels, aluminum alloys, nickel alloys, and cast iron are being welded regularly in industrial applications. Well-known methods of welding are available which being used depending on the type of the materials welded together and application requirement. Like any other sections of a manufactured component, welding parts need to be inspected for required level of quality and integrity. Welding inspection typically consists of a series of quality assessment actions carried out in a certain procedure. It ensures welded joints meet required levels of quality and are fit for a specified purpose. A range of nondestructive testing (NDT) techniques may be used for welding inspection which depends on several factors including geometry and configuration of the joints, material, thickness of the welded parts, and inspection environment. Among the variety of NDT methods, configurations of ultrasonic testing (UT) are identified as efficient and accepted techniques of inspection for welding. Many UT methods are based on traditional techniques. Despite the effectiveness of these techniques, the accuracy and repeatability of the UT can be significantly improved via advanced phased array technology. In this study, phased array UT (PAUT) is used to evaluate the quality of the welding in steel samples. In addition, mechanical properties of the samples were measured by tensile testing and monitored with acoustic emission technique. Results show that the phased array ultrasonic testing can provide localized quality information of the weld and correlate to the mechanical properties (e.g., strength) of the part in welding region.
Development of Paper-Based RNA Amplification Devices for Point-of-Care Detection of HIV
Authors: Adedokun George , Sidhu Gurjit , Wang Gary P. , Fan Z. Hugh 
Published: February 2024

Abstract
Point-of-care (POC) testing of human immunodeficiency virus (HIV) infection is challenging in resource-limited settings, where conventional nucleic acid tests are costly and complex. Paper-based devices offer a low-cost, simple, and rapid alternative, but most of them rely on antibody or antigen detection, which have limitations in sensitivity and specificity. In this work, we develop and evaluate a miniaturized platform for the detection of HIV infection in resource-limited settings. The platform uses low-cost and environment-friendly paper for sample preparation as a nucleic-acid-extraction substrate followed by isothermal amplification in a battery-powered coffee mug and colorimetric detection. Our platform can detect HIV in human serum and plasma samples with high sensitivity and specificity. We demonstrate the feasibility and performance of our platform using clinical samples and compare it with conventional nucleic acid tests.
Study of the Thermal Performance of a Medical Device Packaging System Using Phase Change Material
Authors: Biswal Amrut , Yildiz Salih , Roth Arti , Upadhyaya Sam 
Published: February 2024

Abstract
Medical devices and biologics require to be maintained within specific temperature bands for the product to be safe and effective for treatment. It is a particular challenge during the distribution of products from manufacturing to healthcare facilities when active temperature control is not available. Phase change materials have greatly been used in medical packaging systems to keep the device within the specified thermal conditions. Determining the suitable phase change material as well as the related packaging components are highly important to provide an acceptable environment for medical devices encapsulated by packaging systems. In this study, the thermal performance of a medical device packaging system was investigated. A computational thermal analysis model for the packaging system was conducted. In addition, an experimental set-up was developed, and the packaging system was tested in the environmental chamber. Thermal properties of the PCM obtained by Differential Scanning Calorimetry (DSC) test was validated by in-house experiments as well as a 3D computational model. Furthermore, the full packaging system was tested at −18°C for 24 hours after it was preconditioned at 35°C. The experimental results were compared to the 3D computational analysis. Lastly, the influence of the outer insulation box material and its wall thickness on the thermal performance of the packaging system under the standardized temperature profile (ISTA 7D) which may represent the distribution path of the packaging system was investigated using a computational modeling approach. Through this optimization study, an environmentally friendly, cost-effective, and robust packaging system for medical devices was obtained.
Combined Effect of Hydrogen-Enrichment and Stratification on the Stability and Structure of Premixed Swirl-Stabilized CH4/Air Flames
Authors: Abdelhalim Ahmed , Abdelhafez Ahmed , Nemitallah Medhat A. 
Published: February 2024

Abstract
Hydrogen-enriched flames are a viable solution to reduce greenhouse gas emissions and improve combustion efficiency in gas turbines and industrial applications. Hydrogen has advantages over conventional fuels, such as higher flame speed and a broader flammability range. These benefits lead to more efficient and stable combustion, resulting in improved efficiency, reduced emissions, and increased power output. However, a drawback of hydrogen-enriched flames is the elevated temperature, leading to higher NOx emissions. To tackle this issue, lean swirl-stabilized combustion and stratification techniques are used. The first one enhances combustion efficiency, stability, and reduces emissions, while stratification introduces a non-uniform distribution of fuel, improving the static stability of flames. The DACRS burner is an example of stratified combustors used in gas turbines. By combining hydrogen-enrichment, stratification, swirl-stabilization, and lean operation, combustion systems in gas turbines and industrial combustors can be significantly improved. The present study examined the stability and combustion properties of a hydrogen-enriched, lean, stratified CH4/air flame in a gas-turbine burner. The study varied the hydrogen fraction and equivalence ratio and found that the combination of stratification and hydrogen enrichment had conflicting effects on flame stability. The flame blowout limit remained unchanged, even with up to 20% hydrogen enrichment. NOx emissions were not affected by hydrogen addition up to 20%, but increasing the equivalence ratio promotes NOx formation, as anticipated.
Reduced Order Model of Parametric Resonance of Electrostatically Actuated Cantilever Resonators: Comparison Uniform Versus Non-Uniform Resonators
Authors: Caruntu Dumitru , Flores Rigoberto 
Published: February 2024

Abstract
A comparison of the frequency-amplitude and voltage-amplitude responses of parametric resonance between electrostatically actuated uniform and non-uniform cantilever resonator is conducted. The non-uniform cantilever resonator has constant width and linearly varying thickness. Both microstructures uniform and non-uniform are under soft AC electrostatic actuation. Two Reduced Order Models for predicting the responses of the MEMS cantilever are used in this paper, namely one using one mode of vibration, and another one using two modes of vibration. The Method of Multiple Scales is used to solve the Reduced Order Model with one mode of vibration. A second method is a direct numerical integration is used to solve the Reduced Order Model with two modes of vibration to predict time responses of the MEMS cantilever. A third method uses AUTO 07P, a continuation and bifurcation software, to predict the responses of the MEMS cantilever. A comparison between the three methods is conducted as well.
Analytical and Numerical Analysis of the De Haller Criterion for Low-Pressure Axial Fans
Authors: Fritsche Manuel , Epple Philipp , Delgado Antonio 
Published: February 2024

Abstract
During the design process of low-pressure axial fans, load criteria are often applied to minimize losses and obtain optimal machines. Particularly in the case of decelerated flows, such as in a blade channel of an axial fan, the flow tends to detach and form vortices due to the positive pressure gradient. Exactly 70 years ago in 1953, based on experiments on a linear blade cascade in a wind tunnel, De Haller suggested limiting the velocity reduction between blade outlet and blade inlet to a ratio of 0.75.
This De Haller criterion was analyzed in more detail in the present study. The De Haller criterion is examined on the basis of 16 different three-dimensional analytical impeller designs considering the radial equilibrium with different blade work distributions. Due to the three-dimensional approach in the radial and axial direction on several annular surfaces, it is possible to determine the existing flow field analytically. Due to the variation of the blade work distribution, the impeller is loaded differently, which leads to a change in the flow velocities and thus in the velocity reduction between blade inlet and outlet. The De Haller number can thus be examined using different blade work distributions.
These analytical designs have been simulated using numerical flow simulation methods (Computational Fluid Dynamics - CFD). The three-dimensional CFD model was modelled with ANSYS Workbench 2022R2 and the RANS equations were solved with ANSYS CFX, after performing a detailed grid independence study based on the Richardson extrapolation. From the simulated CFD model, the velocities on the corresponding ring surfaces were evaluated and the associated De Haller number was determined. Two criteria were applied in order to quantify the flow detachment in order to compare the CFD results with the De Haller criteria. The first one is the flow blockage percentage, which indicates how much of the flow is detached and the second one is the wall shear stress on the blade surface, which indicates how well the flow is attached to the blades. Finally, the analytical and the numerical results are compared and the respective De Haller numbers are analyzed. There is a systematic deviation between the analytical design and the numerical simulation. The De Haller numbers of the numerical simulation are always higher than those of the analytical design. This is due to the non-ideal flow deflection in the blade channel. The analytical results and the numerical CFD simulations are explained and presented in detail.
Numerical Investigation of the Mechanical Behavior of Shape Memory Alloy Triply Periodic Minimal Surface Primitive Lattices
Authors: Zaki Wael , Viet Nguyen 
Published: February 2024

Abstract
This work investigates the mechanical behavior of a Schwarz primitive (SP) triply periodic minimal surface (TPMS) lattice made from superelastic nitinol shape memory alloy. The investigation uses numerical homogenization to determine the effective response of a unit nitinol SP cell subjected to a reduced set of periodic boundary conditions that account for the cubic symmetry of the considered SP topology. The simulation of the mechanical behavior of the unit cell is carried out by means of finite element analysis using an implementation of the Zaki-Moumni (ZM) model for shape memory alloys. The analysis considers the influence of temperature and relative density on the mechanical and phase transformation behavior of the SMA SP lattice. The effective stress-strain response of the lattice, in the superelastic temperature range, shows smooth phase transitions characterized by less abrupt changes in the slope of the stress-strain curve compared to dense nitinol. Moreover, later stages of the material phase transformation from austenite to martensite are shown to approach completion in an asymptotic fashion in terms of the applied load, with full transformation corresponding to asymptotically high applied strain. The onset of phase transformation is found to describe an ellipsoidal hypersurface in stress space, which is shown to adequately fit an extended Hill’s loading surface that accounts for the influence of hydrostatic pressure. Moreover, the loading surface is found to evolve with the applied load in a way similar to isotropic hardening, whereby the center of the surface remains fixed whereas the size of the elastic domain increases monotonically with increased cumulated phase transformation, defined as the integral from zero of the magnitude of the differential increment in martensite volume fraction as the load applied to the nitinol lattice cell is varied. The reported findings contribute to understanding the behavior of architected nitinol lattice metamaterials and provide an important element in developing constitutive models that can describe their complex mechanical and functional response.
On the Prediction of Mechanical and Aesthetical Behavior of AM Specimens Through Machine Learning: A Preliminary Study
Authors: Greco Alessandro , Russo Mario Brandon , Gerbino Salvatore 
Published: February 2024

Abstract
3D printing, including the widely used technique of Fused Filament Fabrication (FFF), offers several benefits, such as freedom in design, faster production times, customization, and lightweight. In fact, it has the potential to serve a variety of sectors, from the everyday products market to the industry. However, the properties of FFF parts, in terms of mechanical strength and geometrical accuracy, are strongly influenced by printing process parameters, necessitating thorough investigations.
This preliminary study proposes a comparison between data-driven Machine Learning (ML) models, i.e. Quadratic Regression (QR), Regression Tree (RT), and Neural Network (NN), to predict the impact of printing process parameters on both mechanical (tensile properties) and aesthetical (bending angle, thickness, and flatness tolerance) behavior of additively manufactured tough-Polylactic Acid (PLA) specimens. The investigated models were trained by using experimental data obtained from Design of Experiment (DoE) where the building orientation on plate, the infill percentage and the pattern were varied. An additional dataset was used to test the accuracy of the prediction.
The results suggest that ML models perform well in predicting the tensile properties, particularly the Ultimate Tensile Stress (UTS). At the same time, further investigation is necessary to improve the prediction for aesthetical features.
Multiscale Mechanical Characterization of Cornea With AFM, SEM, and Uniaxial Tensile Test
Authors: Zhai Yingnan , Colmenarez Jose A. , Mendoza Valentina O. , Dong Pengfei , Nunes Kenia , Suh Donny , Gu Linxia 
Published: February 2024

Abstract
Cornea stiffness is associated with the progression of keratitis, aging, and glaucoma diseases. Knowing the microstructure and mechanical properties of the cornea is important for cornea tissue engineering. In this study, the microstructure and mechanical properties of the cornea from African green monkey eye were determined through multiscale methods with atomic force microscopy (AFM), scanning electron microscopy (SEM), and uniaxial tensile test. The cornea samples were dissected from the eyeball of African green monkeys. Cornea microstructures were inspected by SEM and optical microscopy for corneal stroma collagen lamellae. The aligned collagen lamellae have a width of approximately 3–6 μm. The stiffness map of cornea stroma with scanning regions of 10 × 10 μm2 and 5 × 5 μm2 was detected by AFM indentation test. The average Young’s modulus determined by AFM was 238.2 ± 32.7 kPa, which is on the same scale as the toe modulus (402.1 ± 176.7 kPa) of the stress-strain curve (linear region of 0%–5% strain) obtained from uniaxial tensile test. The heterogeneity of corneal stroma stiffness was presented in the stiffness map with line-shaped and band-shaped regions showing higher Young’s Modulus (around 250 kPa). The width of the band-shaped region is around 3.7 μm referring to collagen lamellae, while the adjacent arbitrarily shaped region with lower Young’s modulus (&lt; 70 kPa) on the stiffness map refers to keratocytes. Corresponding histograms show two-phase characteristics with one peak at a lower Young’s modulus range of 0.027–0.574 kPa, and another peak at a higher Young’s modulus in the range of 250.0–263.3 kPa. Monkey cornea shows heterogeneous and nonlinear mechanical properties over the scale of the tests.
A Manufacturing Compensation Method As Applied to CFRP Components in Aero Engines
Authors: Lööf Johan , Frampton Andrew , Wärmefjord Kristina , Söderberg Rikard 
Published: February 2024

Abstract
In this paper the focus is on applying compensation to the manufacturing process based on the results of shape distortion simulation for composite CFRP (carbon fibre reinforced polymers) parts. The objective of the simulation is to predict the deformation due to the manufacturing process to enable the lay-up, compression and mold tool to be modified to compensate for these distortions to achieve a net shape component at the end of the process. A case study is presented to demonstrate how the results from the shape distortion simulation can be used to compensate for the global deformations. This case study describes the complete process on how to go from a nominal CAD model (design intent) towards to a virtually designed compensated lay-up and mold tool.