bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the CO2 concentration at the surface of photosynthetic mesophyll cells
Authors: Márquez Diego A. , Stuart‐Williams Hilary , Cernusak Lucas A. , Farquhar Graham D. 
Published: February 2023

Summary

We present a robust estimation of the CO2 concentration at the surface of photosynthetic mesophyll cells (cw), applicable under reasonable assumptions of assimilation distribution within the leaf. We used Capsicum annuum, Helianthus annuus and Gossypium hirsutumas model plants for our experiments.

We introduce calculations to estimate cw using independent adaxial and abaxial gas exchange measurements, and accounting for the mesophyll airspace resistances.

The cw was lower than adaxial and abaxial estimated intercellular CO2 concentrations (ci). Differences between cw and the ci of each surface were usually larger than 10 μmol mol−1. Differences between adaxial and abaxial ci ranged from a few μmol mol−1 to almost 50 μmol mol−1, where the largest differences were found at high air saturation deficits (ASD). Differences between adaxial and abaxial ci and the ci estimated by mixing both fluxes ranged from −30 to +20 μmol mol−1, where the largest differences were found under high ASD or high ambient CO2 concentrations.

Accounting for cw improves the information that can be extracted from gas exchange experiments, allowing a more detailed description of the CO2 and water vapor gradients within the leaf.
Muscle fatigue during maximal eccentric‐only, concentric‐only, and eccentric‐concentric bicep curl exercise with automated drop setting
Authors: Nuzzo James L. , Pinto Matheus D. , Nosaka Kazunori 
Published: February 2023

AbstractConnected adaptive resistance exercise (CARE) machines are new technology purported to adjust resistance exercise loads in response to muscle fatigue. The present study examined muscle fatigue (strength loss, fatigue perceptions) during maximal eccentric‐only (ECCmax‐only), concentric‐only (CONmax‐only), and coupled ECC‐CON (ECCmax‐CONmax) bicep curl exercise on a CARE machine. Eleven men and nine women completed the three protocols in separate sessions and in random order. All protocols included 4 sets of 20 maximal effort muscle contractions. Strength loss was calculated as Set 4 set end load minus Set 1 highest load. The CARE machine's algorithm adjusted resistances automatically, permitting continued maximal effort repetitions without stopping. Consequently, all protocols caused substantial fatigue. Women were most susceptible to strength loss from exercise that included maximal efforts in the ECC phase, whereas men were most susceptible to strength loss from exercise that included maximal efforts in the CON phase. With ECCmax‐only exercise, ECC strength loss (mean ± SD) was similar between men (55.9 ± 14.1%) and women (56.4 ± 10.8%). However, with CONmax‐only exercise, men and women experienced 55.6 ± 6.2% and 35.3 ± 8.7% CON strength loss, respectively. With ECCmax‐CONmax exercise, men experienced greater ECC (62.9 ± 7.7%) and CON (77.0 ± 5.3%) strength loss than women (ECC: 48.5 ± 15.7%, CON: 66.2 ± 12.1%). Heightened perceptions of fatigue and pain of the exercised limb were reported after all protocols. Women generally reported more biceps pain than men. The results illustrate CARE technology delivers ECC‐only and accentuated ECC exercise feasibly. Acute responses to repeated maximal effort bicep curl exercise with such technology might differ between men and women depending on muscle contraction type.
Engine Mounting Systems for Electric Powertrains: Mounting Layouts and Design Parameters
Authors: Kaul Sudhir 
Published: February 2023

Abstract
The vibroacoustic characteristics of electric powertrains are well known to significantly differ from internal combustion engines. A relatively very high power-to-torque density makes a three-phase permanent-magnet synchronous motor (PMSM) very appealing for electric powertrains, but its electromagnetic characteristics typically result in high frequency noise and vibration. While the vibration response in internal combustion engines is generally evaluated up to 100 Hz, electric drive trains are known to exhibit a response ranging from 1 to 10 kHz. As a result, multiple studies in the recent literature have investigated several designs for engine mounting systems that could be used to address some of the specific issues such as internal resonances, wave effects, high frequency noise and vibration, etc. It has been widely reported in the literature that force transmissibility and noise radiation can be significantly underestimated at relatively higher frequencies without directly modeling the inertial properties of the engine mounting system. Some of the mounting system layouts that have been investigated in the literature include the three-point or four-point saddle mounting configurations, the cradle type pendulum mounting configuration, etc. This paper performs a comparative analysis for a few of the commonly used mounting system layouts to identify the pros and cons of the design strategies specifically aimed at vibration mitigation in electric powertrains. A spatial model that has been previously validated is used to compare three different mounting system layouts. Since viscoelastic properties are known to exhibit a strong influence from excitation frequencies, the spatial model that has been used in this study incorporates the properties that are associated with high frequency response of the engine mounting system. Force transmissibility plots are used to evaluate the mounting layouts and specific design parameters associated with the engine mounting system. Results indicate that the four-point saddle mounting configuration provides a good balance between transmissibility at low frequencies and high frequencies. Models presented in this study can be used to determine an optimal mounting configuration for an electric powertrain.
Testing of an Articulated Prosthetic Ankle
Authors: Davidson Michael , Daher Noha , Dudley Robert , Fryer Thomas , Schaepper Johannes , Tran Duc 
Published: February 2023

Abstract
This paper presents our initial evaluation of a prototype ankle prosthesis with a one degree-of-freedom joint-axis featuring a biologically correct joint-axis alignment with hydro-pneumatic passive-resistance. The purpose of this biomedical device is to improve stance stability, increase balance confidence, and reduce the contralateral limb’s kinetic stresses in gait, sitting, and standing. The objective of this case study was to test the safety and feasibility of the device on an active single-limb male amputee. A single subject with a trans-tibial amputation was fitted with the prototype ankle prosthesis and tested against his prescribed daily use prosthesis. In addition to extended walking on level ground, kinematic and kinetic measures were taken in an 18-camera motion capture lab with two in-floor force platforms. These measures assessed body symmetry in the timed-up and go (TUG) test and five times the sit-to-stand (5xSTS) test while the subject used this prototype device. Balance confidence was assessed using the activities-based balance confidence (ABC) questionnaire. While performing the 10MWT, the subject was able to ambulate at a maximum velocity of 1.34 m/s and an average of 1.32 m/s. In the six-minute walk test (6MWT), the subject was able to walk a distance of 416.84 meters (a velocity of 1.16m/s). Although kinetic symmetry did not improve, kinematic symmetry of both lower extremities did improve in sitting and standing. In total, the subject walked with the device for 2 km. We found the device safe on a single amputee subject in a controlled environment and feasible for future testing on ramps and lower level ambulators.
Exploring Alternative Methods for Simulating Lightning Mechanical Damage Effects on Carbon/Epoxy Laminates
Authors: Lee Juhyeong , Yang Bin , Fu KunKun 
Published: February 2023

Abstract
This study introduces three relatively simple predictive material models simulating lightning mechanical damage effects on carbon/epoxy laminates. The alternative lightning mechanical damage models proposed in this work are (1) the conventional weapons effects program (CONWEP) model, (2) the coupled eulerian-lagrangian (CEL) model, and (3) the smoothed-particle hydrodynamics (SPH) model. These models are developed for 100∼500 kA peak current amplitudes based on total chemical potential energy equivalent to lightning shock wave energy. More specifically, assuming that all lightning shock wave energy is instantaneously converted to chemical potential energy in explosive TNT, two primary factors — an TNT explosive weight and stand-off distance (referring to the distance from the explosion center to the target structure) — are determined to develop CONWEP, CEL, and SPH models. The lightning shock wave model previously published by the authors is considered as a baseline. The predicted dynamic responses (i.e., pressures, displacements, strain rates, and dynamic pressures) and corresponding failure modes are compared with those from the baseline and relevant models available in open literature.
Overall Mechanical Properties of Self-Healing Composites: Effects of Microcapsules Shape, Volume Concentration, Shell Thickness, and Material Properties
Authors: Kazemi Zahra , Azami Mohammad 
Published: February 2023

Abstract
The present work investigates the influence of embedding spherical and spheroidal capsules containing the healing agent within the base polymers to create a self-healing effect on the overall mechanical properties of the entire medium, using numerical and analytical homogenization approaches. The effects of geometrical and mechanical parameters, including capsule shape, the healing agent volume concentration, the capsules shell thickness, and mechanical properties on the overall responses of the self-healing composites are studied. A square-array configuration is assumed for the distribution of the capsules. This idealization enables computing the behavior of such composites computationally via FE analysis and variationally using Hashin-Shtrikman upper bound by taking a unit cell composed of a cube of the matrix with a perfectly bonded capsule at its center. The boundary conditions on the unit cell are applied in a way that the deformation of the unit cell captivates the overall mechanical responses of the entire medium. Our results show a general decrease in the overall properties of the composites, which can be alleviated by increasing the thickness of the capsules shell or using a stiffer shell. Additionally, we show that the geometry of the capsule shell plays a role in reducing the drop in the overall properties of the composite.
Compression Energy Stored in an Additively Manufactured Mesostructure
Authors: Schmitz Anne 
Published: February 2023

Abstract
One facet of sustainable manufacturing is minimizing material usage and waste. This is done by creating latticelike infills for components, i.e. mesostructures. The goal of this study was to quantify the compression energy absorbed by a stereolithographic (SLA) manufactured mesostructure. Fifteen specimens were printed using a Form 2 SLA printer from Formlab. After printing, the specimens were washed in isopropyl alcohol to remove any uncured resin. The specimens were printed as 80 × 80 × 20 mm blocks for compression testing. The structure of the block was a novel, open-source mesostructure designed by Andreas Bastian. The specimens were compressed in a Tinius Olsen compression testing machine. Using Matlab, these compression curves were numerically integrated to obtain energy absorbed as a function of relative displacement. The SLA structures absorbed 0.5–10.9 Joules at 40% relative displacement. As modulus of the base SLA material increased, so did the energy absorbed by the structure (r = 0.867, p &lt; 0.001). This indicates the compression behavior SLA structures may be predicted through modeling to fine tune the structure. This fine tuning could then be used to maximize the energy absorption of the structure for a desired application, e.g. football helmet cushioning.
Simulating a Piezoelectric-Haptic MEMS Actuator in Low-Frequency Vibration
Authors: Benson Alexander , Carl Seth , Duan Shawn 
Published: February 2023

Abstract
When developing a haptic mouse, the authors aimed to exploit a documented phenomenon in which tangential loads to a user’s finger are aliased with positional cues. A flextension-style microelectromechanical system (MEMS) was designed to increase the range of actuation possible with the piezoelectrics preferred by nearly 10. The flextensional system converted the piezoelectric actuator into a two-degree-of-freedom (DOF) system, with the piezoactuator as a cyclic force. The actuator was intended to provide a wide range of feedback, the primary modality being the aliased positional cues with vibration as a secondary feedback mode. A single axis of the complete system was studied and designed for simplicity.
Simulations of a piezoelectric actuator vibrating with and without a human finger resting on the actuator were studied. The actuator resembles a two-DOF system without a finger. With a finger, the actuator becomes a three-DOF system. All systems were simulated using MATLAB’s ODE45 solver.
The quality of a single-degree-of-freedom reduction depended on whether the user’s finger was considered. Without a finger, no significant deviations in the system’s behavior were found; the equivalent spring, mass, and damper coefficients match those calculated by standard reduction methods without complication. The addition of a finger complicated the simulation. The frequency behavior of the single-degree-of-freedom system dropped an order of magnitude below the frequencies of the multi-degree-of-freedom system. This drop resulted in discrepancies between the simulated behavior of the multi-degree-of-freedom and its single-degree-of-freedom equivalent.
Thermo-Mechanical Behavior of Multi-Layer Deposition for Wire Arc Additive Manufacturing of Structural Steel: Wire Arc Additive Manufacturing
Authors: Kumar Amritesh , Bag Swarup , Srivastava V. C. , Amin M. Ruhul 
Published: February 2023

Abstract
Wire arc additive manufacturing (WAAM) process, following the directed energy deposition (DED) technique, has evolved as one of the most prominent additive manufacturing (AM) technologies to fabricate large and intricate shapes of metallic components. The physical basis of the WAAM process is associated with rapid heating, melting, layer-by-layer melt deposition, solidification, and moderate cooling rate of the fabricated part. Consequently, different regions of the additive manufactured part experience variable heating and cooling cycles due to repeated heating and cooling. The continuously varying transient thermal cycles lead to residual stresses and distortion in fabricated components, mainly influenced by the temperature gradient along the build direction. The generation of residual stress and distortion result in warping, delamination, and unfavorable fatigue properties of the AM components. The in-situ prediction of transient temperature profile and its impact on residual stresses in an arc-based DED technique is practically impossible by any contact measurement technologies. As the cooling or idle times between the successively deposited layers play a significant role in the thermomechanical behavior of as-deposited materials, the inclination towards developing a numerical model by considering different process variants in the layer-by-layer deposition process is evolving. In the present work, a finite-element-based thermo-mechanical 3D model is developed for the WAAM process by triggering the effect of the inter-pass cooling period. The model results are validated with experiments reported in independent literature. Increasing the inter-layer dwell time decreases built material’s peak temperature and residual stress. At the same time, the distribution of effective stress along the built material’s center line increases with idle times.
Evaluation of Forward-Facing Child Safety Seat Harness Retainer Clip Position in 35 mph Frontal Barrier Crash Tests
Authors: Bell Lauren , Meyer Steven , Herbst Brian 
Published: February 2023

Abstract
The National Highway Traffic Safety Administration (NHTSA) recommends that children ages 4 to 7 years old should travel in a forward-facing child safety seat (FFCSS) with a harness until reaching the maximum weight or height limit allowed by the car seat manufacturer. There are five types of FFCSS, including convertible, combination, all-in-one, forward-facing only, and integrated (built-in). In the United States, most of the harness systems in FFCSS also include a retainer clip or chest clip; this is a plastic clip that holds the harness shoulder straps together over the child’s chest. NHTSA, National Child Passenger Safety Board (NCPSB), and Safe Kids Worldwide recommend that with the child buckled and the straps tightened snugly, the harness retainer clip should be secured and then positioned at the child’s armpit level. According to NHTSA, the purpose of the clip is as a pre-crash positioner, holding the harness straps together for correct positioning in the event of a crash.[1]
Analysis of child dummies placed in various types of FFCSSs and in various makes and models of vehicles during 35 mph New Car Assessment Program (NCAP) frontal crash tests were used to draw conclusions relative to how the child safety seat was loaded during the collision. Comparison of the position of the clip before, during, and after the crash test was assessed. This additional data was reviewed relative to the University of Michigan Transportation Research Institute (UMTRI) Research Review’s Crash Protection for Child Passengers conclusion that “clips slide down the straps as the child presses forward or may break if sliding is restricted.”[2] Also, for a subset of the crash data collected, direct measurement of the clip displacement was measured. Analysis of this data was used to draw conclusions regarding how much clip movement is typical in a FFCSS when installed in the rear occupant positions of vehicles in a 35 mph frontal barrier crash test.
Experimental Core Flooding Test for Formation Damage During Gel Treatment
Authors: Elsharafi Mahmoud , Green Jesse 
Published: February 2023

Abstract
In mature oil fields, the success of gel treatment results depends on the ability of the gel to reduce the high permeable formation without damaging to low permeable formation. Formation damage refers to the extent of damage reservoir rocks face from various drilling techniques and/or chemical treatment during well completion. A dynamic filtration test was used to investigate this effect using distinct core samples, brine concentrations and preformed particle gels. The effect of high pressures applied on the particle gels on various core samples with various permeability ranges was determined. These gels were pushed into the core holder with samples and the core permeability change was calculated. Different constant pressures were used to push the piston behind the gel samples. Then, the gel was flown around the core sample and collected in the outlet container. Various hardware was used to tighten the apparatus and provide connection between brine source, syringe pump, piston accumulator, core holder, and flow outlet container. The damage on the core was evaluated by comparing the original core permeability and the core permeability after gel treatments. Pressure gauges were used to measure the pressure drop across the core samples. The penetration of the particle gels into the low permeable formations can be decreased by the best selection of gel types, particle sizes, and brine concentrations under the reservoir condition. This work results can be used to select the best gel types for the right reservoir condition such as reservoir permeability, and reservoir pressure.
Assessment of Soccer Ball Inflation Pressurizations and Risk of Brain Injury
Authors: Perkins Richard Allen , Bakhtiarydavijani Amirhamed , Prabhu Raj 
Published: February 2023

Abstract
In this study, we employ a finite element analysis to determine brain injury risks resulting from impacts caused by a soccer ball to the player’s head at various ball inflations. The repetitive ball-head impacts in soccer are a cause for concern considering the literature showing neurodegeneration in soccer pressures. Standard soccer ball inflation pressurizations for a size 5 ball are in-between approximately 60kPa and 110kPa; the effect of these pressurizations on injury risks has not been widely studied. This finite element analysis implements previously validated finite element models of an adult 50th percentile human head and regulation size 5 soccer ball. The results of the simulations are evaluated using existing kinematic injury metrics (HIC15 and BrIC) and peak pressure, Von Mises stress, and maximum principal strain values throughout the brain. The results of our simulations show increasing HIC15, peak pressure, and peak maximum principal strain values for increased ball pressurizations. It is found that increasing the ball pressure increases the rate of energy transfer from the soccer ball to the head, which translates to higher injury metrics and brain stresses and strains. Additionally, the peak contact area between the soccer ball and the head is inversely proportional to the ball pressurizations. Increasing soccer ball inflation pressures can lead to increased brain injury risks due to soccer heading.
Understanding the Expected Deformation of Rectangular Ductwork
Authors: Schaff Cameron , Crispi Matthew , Liu Jane , Peddieson John , Idem Stephen 
Published: February 2023

Abstract
A study was performed to investigate the effects of aspect ratio, material gauge, material properties, joint spacing, loading type and magnitude on the mechanical performance of rectangular ductwork. The SMACNA Industrial Duct Construction Standard (1st and 2nd Editions) rectangular ductwork design standards were reviewed, and theoretical equations contained in the existing literature were identified and evaluated. Allowing for round-off error, the calculations performed in this investigation agreed closely with the SMACNA approach. Finite element predictions of duct deformation were intermediate to the DMI experimental data and those obtained using the SMACNA design procedures, for both 10 gauge and 16 gauge wall thicknesses and twelve load cases.
Non-Linear Analysis of Beam-Reinforced Thin Plates for Modeling Rectangular Duct Systems
Authors: Crispi Matthew , Liu Jane , Peddieson John , Idem Stephen 
Published: February 2023

Abstract
This study introduces a beam-reinforced plate (BRP) finite element model to predict the deformation behavior of a rectangular duct system under positive gauge pressure, and further investigates the existing design procedures employed in practice. A commonly used methodology is to model rectangular duct systems subjected to internal pressure as individual thin plates to predict maximum deflections and set stress limitations. One of the assumptions these existing models are based on is to assume the stiffness of reinforcements is infinite, which obviously is not consistent with the real duct behavior. The proposed BRP model not only accounts for the deformation of the stiffeners, but also the geometric non-linearity of the plates under a uniform internal pressure. By comparing deflection predictions from a whole duct finite element model, it is shown that that the BRP model can predict the deformation behavior accurately under certain circumstances. Parametric studies were performed to understand how geometric variables affect the deflections of duct panels. Therein limitations of the proposed model are discussed and defined. Based on these limitations, further research is recommended to develop plate models that can accurately predict the behavior of complicated duct systems.