bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Impact of Different Backbone Architecture on Autonomous Vehicle Dataset
Authors: Ding Ning , Eskandarian Azim 
Published: February 2024

Abstract
Object detection is a crucial component of autonomous driving, and many detection applications have been developed to address this task. These applications often rely on backbone architectures, which extract representation features from inputs to perform the object detection task. The quality of the features extracted by the backbone architecture can have a significant impact on the overall detection performance. Many researchers have focused on developing new and improved backbone architectures to enhance the efficiency and accuracy of object detection applications. While these backbone architectures have shown state-of-the-art performance on generic object detection datasets like MS-COCO and PASCAL-VOC, evaluating their performance under an autonomous driving environment has not been previously explored. To address this, our study evaluates three well-known autonomous vehicle datasets, namely KITTI, NuScenes, and BDD, to compare the performance of different backbone architectures on object detection tasks.
Research on Integrated Forming Process of Flange Nuts by Three-Roll Skew Rolling and Piercing
Authors: Siyuan Chen , Fei Lin , Xuedao Shu , Zixuan Li , Haijie Xu , Jinrong Zuo , Ying Wang , Yimin Deng 
Published: February 2024

Abstract
In order to realize the high-quality production of large-size flange nuts, a new integrated forming process of flange nut blank by three-roll skew rolling and piercing is proposed in this paper. Different from the traditional hot upsetting and forging process, this new process integrates perforation and flange forming, and the whole process goes through the perforation stage and the reducing stage. Based on Simufact.Forming 15.0, the finite element simulation model forming flange nuts by three-roll skew rolling and piercing was established, and the feasibility and forming law of flange nut blank manufactured by the new process were explored. Seven main process parameters (speed of the barrel roller, feed angle of the barrel roller, plug advance, speed of the disc roller, feed angle of the disc roller, radial feed speed of the disc roller, axial traction speed of the chuck) were selected and imported into the simulation model for single factor analysis. The influence of different process parameters on the force and energy parameters of the piercing section and the forming section was explored, and the feasibility of forming the flange nut blank by the three-roll skew rolling and piercing process was verified.
Ungrading in a Mechanics Curriculum: Identifying Gaps in Student Metacognition
Authors: Schmitz Anne 
Published: February 2024

Abstract
National data has shown a gap in metacognition or self-awareness where students tend to rate themselves higher in proficiency on career-ready skills than employers. The goal of this study is to identify metacognition gaps in the study habits of students in a subset of mechanics courses. Based on modern pedagogical research, two mechanics courses were structured as “ungraded” with a transparent “high-structure” for success where grades were based solely on standards-based grading of summative exams and lab practicals. Students were asked to rank the formative assessments (book reading assignments, quizzes, homework, and lab assignments) from most to least helpful to their learning. In week 7, the students in the sophomore mechanics course (strength of materials) rated labs as most helpful. However, grades were found to be most correlated with book reading notes. This shifted in week 14 where students found homework most helpful but labs were most correlated with grades. The students in a junior/senior mechanics course (machine component design) also rated labs most helpful initially in week 7. However, grades were found to be most correlated with homework. This also shifted in week 14 where students viewed homework as most helpful. This aligned with the grade book data that showed homework to be most correlated with grades. These results show that the sophomore students in this study exhibited larger gaps in metacognition of effective study habits than the junior/senior engineering students. This indicates that engineering students may not develop effective study habits until their senior/junior year of college. This supports the course design strategy of “high-structure” that is recommended in the literature.
eVTOL UAV Conversion to Hydrogen Fuel-Cell Power Source for Enhanced Endurance
Authors: Almesafri Nouf , Alhammadi Majed , Zafar Sayem , Dos Santos Gustavo 
Published: February 2024

Abstract
A study is conducted to investigate the integration of a hydrogen fuel cell power system to a small electric vertical take off and landing (eVTOL) Unmanned Aerial Vehicle (UAV) at Technology Innovation Institute (TII), Abu Dhabi. A hybrid power system is used comprising of hydrogen fuel cell for forward flight and lithium polymer batteries of vertical flight during take-off and landing phase. The hybrid power system is proposed as a substitute to the existing batteries in order to enhance the endurance of eVTOL UAVs. The eVTOL UAV used in this study is Dronepoulis ESA-90 which has four vertical flight motors and a single forward flight motor. Data simulations are conducted for the cruise power of 750 W which is consumed by the forward flight motor. The results show that the flight endurance of the UAV increased from 90 min to 272 minutes when hydrogen fuel cell power system is used. Further studies show that increasing the hydrogen pressure in the cylinder and increasing the size of the cylinder increased the flight endurance of the UAV. Increasing the size of the cylinder can potentially increase the flight endurance of the UAV as long as the overall weight remains within the maximum take-off weight limit.
Enhanced Performance of Laser Dressed Wheels in Internal Grinding of Bearing Steel Parts
Authors: Bindgi Sudheendra , N. Ramesh Babu 
Published: February 2024

Abstract
Internal griding is used for manufacturing of bearing inner races. As the process involves larger area of contact between the wheel and work material, the wear of abrasives as well as the chip entrapment in the pores of the wheel cause the deterioration of wheel performance in internal grinding of parts. This will, in turn, result in huge rejection of parts. Thus, the wheel is periodically dressed using a single point diamond dresser to remove the worn abrasives and grinding debris entrapped in pores of the wheel. Though this method is widely employed in industry, it causes excessive loss of wheel material and also generated inconsistent topography on the wheel surface due to continuous wear of the dresser. This paper covers the development of on-line laser dressing system made on a production grinder and different studies to evaluate the technical feasibility of on-line laser dressing of wheels. The performance of laser dressed wheels was evaluated by different aspects such as specific grinding energy, wheel wear, grinding ratio, roundness and the finish on the ground parts. By comparing the performance of laser dressed wheel with that of the diamond dressed wheel, the technical merits of online dressing of grinding wheels was demonstrated.
Optimized Thermal Performance of CPU Coolers Using Different Working Fluids
Authors: Das Shuva , Molki Majid 
Published: February 2024

Abstract
Over time there has been a notable increase in the use of computers in all fields. The processor technology is equally upgrading over time. Efficient processors demand efficient cooling. Thus, the CPU cooler research becomes significant. In this study, we have investigated a desktop computer CPU cooler. The heat transfer mechanism in such CPU coolers is conjugate heat transfer. With heat pipe temperature and Reynolds number ranging from 35° to 95°C and 100 to 2000, a Nusselt number correlation is obtained considering air as the working fluid. Then, the case is further examined for three working fluids, Helium, Hydrogen, and CO2, which have varying thermophysical properties. This analysis is then performed, maintaining two criteria. The first criterion maintains the same Reynolds number for all the working fluids. The second criterion maintains the same airflow range regardless of the individual Reynolds number. Helium shows four times better heat transfer than air for a fixed Re. The other case also shows Helium as the leading heat rate solution. Overall, this study discusses the potential of using various working fluids in designing thermally efficient CPU coolers.
Modelling of a Drone to Analyze Dynamic Instabilities With its Delivery System
Authors: Marquez Eleazar , Luna Ivan 
Published: February 2024

Abstract
In the study herein, an alternative mathematical model was developed with the intention of understanding the dynamics associated with the instabilities generated by an UAV and its delivery system, particularly the coupled nonlinearities of the system, and thus provide feedback to optimize drone design. In this regard, a Newton-Euler methodology was adopted to establish the parameters of the equations of motion of the target UAV system, which consisted of a combination of a platform and delivery system operating simultaneously. Specifically, the UAV platform was modelled as a rigid body which accounted for a total of six-degrees-of-freedom, three corresponding to the linear (position) directions of the system, and three correlative with the rotational (attitude) directions, thus elucidating drone maneuverability during operation. In this context, the delivery system, attached to the center of the UAV platform, was simultaneously modelled to account for oscillation patterns relative to a single coordinate of the platform, as well as the payload of the package unit. The response of the UAV and its delivery system was captured by imposing various initial conditions, while a power spectral density function was approximated to elucidate the dynamic characteristics of the drone.
Fastenerless Joining of Carbon Fiber Reinforced Thermoplastic Composite to Aluminum
Authors: Phadatare Akash , Jo Eonyeon , Pokkalla Deepak Kumar , Kim Seokpum , Vaidya Uday 
Published: February 2024

Abstract
Continuous efforts are underway for the reduction of the structural weight of transit through the introduction of a multi-material metal-composites system. There are major challenges in joining dissimilar materials to result in optimum structural integrity. The conventional joining techniques have limitations in terms of preparation time, weight penalty resulting from adhesives, and uncertainty in joint integrity. Recently adoption of macro scale mechanical interlocking in the adhesive joining resulted in significant improvement of joint performance. This made mechanical interlocking gain an attention for hybrid joining. In this study, fastenerless method of mechanical interlocking based on Japanese wood joining craft is considered for joining carbon fiber-reinforced polyamide thermoplastic composite to aluminum. Different interlocking joining designs (IJDs) were developed. The joints were obtained by force-fitting the male into the female counterpart. Here the male and female segments joined at macro level with no joining integrity at the interface. Further, these joints were tested and evaluated for tensile strength. A finite element analysis (FEA) model is developed for stress analysis and studying failure mechanisms of the IJDs. It was observed that the geometry of IJD dictates the failure mode and material composition governs the maximum strength achieved by a particular IJD. Each IJD showed higher load capacity with metal as a female counterpart to the composite compared to other way round.
In-Situ Calibration for Load Cells in 3d Printed Bipedal Robot Using 3D Modeling in Computer-Aided Design Environment
Authors: Le Xuan Tung , Herron Connor W. , Leonessa Alexander 
Published: February 2024

Abstract
This paper presents an in-situ calibration for load cells in a bipedal robot. Here the problem is tackled by using mechanical simulation using the 3D Computer-Aid Design (CAD) modeling of the robot. Since mechanical simulation is very high computational power demanding and it needs to be very precise for the calibration, new simplification methods are used for the robot CAD modeling to make the simulation able to run on ordinary personal computers. The results show that the new in-situ calibration method is easy to work with, the force values still meet the requirement for calibration and the computer only needed 10–12 seconds to run for each simulation.
A Three-Electrode Three-Dimensional Impedance-Based Biochemical Sensor for Food Safety Applications
Authors: Zamiri Athena , Shavezipur Mohammad 
Published: February 2024

Abstract
This work presents an innovative structure for impedance-based MEMS biochemical sensors with three electrodes that are stacked on top of one another, creating a 3D geometry with a parallel-plate configuration. The sensor is designed to mimic the porous surface of fresh produce for food safety applications. To characterize the sensor’s electrochemical behavior, we use a chemical, di-ethylhexyl phthalate (DEHP). The sensor is fabricated using PolyMUMPs and is exposed to different concentrations of DEHP, ranging from 0.02 ppm to 20 ppm. Three electrodes used in the sensor create two pairs of sensing electrodes (top-middle electrodes and middle-bottom electrodes) and their impedance spectroscopy response is recorded. The EIS test results show that similar to conventional interdigitated sensors, each pair of electrodes can detect the change in concentration of DEHP, and their Nyquist responses display diffusion effect, charge transport and double-layer effect. Furthermore, due to the parallel-plate geometry of the electrodes, the electrostatic effect is noticeable resulting in a region at the higher end of the frequency spectrum where the electrostatic capacitance affects the Nyquist response. This characteristic of the response is of great importance to detect the internalization of microorganisms when the device is used for pathogen detection.
Energy Sensors and Absorbers Based on Nanoscale Magnetic Tunnel Junction Metamaterials
Authors: Mengesha Betelhiem N. , Estevez Hernandez Juan , Feutmba Arnold , Tyagi Pawan 
Published: February 2024

Abstract
This paper explores nanoscale energy sensors and absorber metamaterials that can be used in various applications, such as solar cells and infrared detectors. It is possible to gain highly efficient and adjustable energy absorption, creating absorber metamaterials at the nanoscale that enhance the performance of solar cells. These metamaterials are based on molecular spintronics devices (MSD) and magnetic tunnel junctions (MTJ). The pillar shaped MTJs are made of two ferromagnetic metals separated by an insulating barrier, such as aluminum oxide (AlOx). The manufacturing process includes photoresist spin coating on a silicon wafer, photolithography, thin film sputtering, and liftoff. Following fabrication, the top and bottom electrodes are covalently bonded by a single molecule magnet (SMM) on the exposed side edges for strong magnetic coupling that changes the magnetic properties of both ferromagnetic metals. This study has considered different thin film deposition materials, configurations, and thicknesses. Magnetic field resonance and light reflectance measurements have been performed before and after molecule attachment to understand the molecule effect on the metamaterials’ energy absorption behavior. The Electron Spin Resonance (ESR) test revealed that the devices shifted following molecule attachment in both acoustic and optical modes. Moreover, due to molecule attachment, there have been significant alterations in the MTJ’s electromagnetic wave absorption characteristics with about 49% less reflectance. This metamaterial has various potential applications in aerospace, renewable energy, sensing, imaging, and communication. It is also a cheaper alternative to traditional solar cells and can inspire the development of smart metamaterials with selective absorption and tunable response.
A Novel Solar Absorption Cogeneration System With an Adjustable Cooling-to-Power Ratio
Authors: Alghamdi Abdulmajeed M. , Sherif S. A. 
Published: February 2024

Abstract
In this work, a novel solar double-effect absorption combined cooling and power (DECCP) system with an adjustable cooling-to-power ratio is proposed. This cogeneration system uses water-LiBr as the working fluid. The novel cycle upon which this system is based has been mathematically modeled, simulated, and parametrically analyzed to generate the system’s performance characteristics for several scenarios. The performance has been compared with those of other similar combined cogeneration cycles. It was found that the proposed cycle outperforms the other cycles from the vantage point of the power produced and the cycle’s ability to produce cooling. For specific operating parameters, the DECCP cycle achieves an exergetic efficiency that varies between 36.55–59.13% based on the refrigerant split ratio used. An effective operating strategy is proposed for the cycle when it is powered by solar energy.
Numerical Analysis of Air Curtain Jet Blast Deflector
Authors: Fletcher Stuart , Walters D. Keith , Leylek James H. 
Published: February 2024

Abstract
This paper presents the numerical results for a novel proof of-concept jet blast deflector design based on use of a high-speed air curtain to deflect aircraft engine exhaust gases during aircraft carrier launch operations. The resulting flowfield represents a supersonic turbulent jet-to-jet interaction that is highly dependent on the location, geometry, and flow conditions of the engine exhaust gases and the air curtain outlet. The complex fluid dynamics was numerically analyzed with the open source computational fluid dynamics (CFD) solver flowPsi, using a k-ω SST turbulence model. The domain was modeled based on the launch of a dual-engine fighter jet and includes an air curtain set at varying angles to the carrier flight deck. Simulations were run to investigate the feasibility of substituting actively cooled aircraft carrier jet blast deflectors with a high velocity air curtain, capable of dissipating aircraft jet exhaust during the catapult launch, with the intention of reducing annual maintenance costs and expenditures. Simulations are performed for several different exhaust conditions representative of actual fighter jet operation, including with and without afterburner. Results obtained from the simulations show promising capabilities and are presented and discussed in detail.
Mechanical Properties of Stretchable Multifunctional Ecoflex Composites for E-Skin Applications
Authors: Guler Zeynel , Jackson Nathan 
Published: February 2024

Abstract
Stretchable silicone elastomers are widely used in various applications such as robotics and wearable technologies due to their mechanical tunability, widespread availability, low cost, and ease of manufacturing. However, elastomers typically have no functional properties, and are often just used for their unique mechanical properties. Recently composite materials using an elastomer backbone have been developed to add functionality such as electrical conductivity, piezoelectric, and magnetic properties. However, research on the effects of mechanical properties due to the addition of these nanoparticles is limited, especially at the micro scale. This study investigates the feasibility of fabricating highly stretchable Ecoflex 00-30 composites containing various nanoparticles and the mechanical properties of these composites. Various nanoparticles were investigated with varying concentrations, and we investigated macro and micro sized samples. Nanoparticles investigated include lead zirconate titanate, neodymium iron boron, Terfenol-D and mixtures of these with varying concentrations up to 80 wt%. The 80% NdFeB composite demonstrated a remanence value of 0.75 T. The piezoelectric properties of PZT/Ecoflex were 1.7 pC/N (d33), and the Terfenol-D composite demonstrated a Villari effect. Most particularly, mechanical behavior of the samples has been comprehensively analyzed based on the tensile tests of different sized specimens. With increasing particle concentration, a promising elevation in the elastic modulus along with a high ductility was obtained.
Material and mechanical properties of young basalt in drill cores from the oceanic island of Surtsey, Iceland
Authors: Jackson M.D. , Heap M.J. , Vola G. , Ardit M. , Rhodes J.M. , Peterson J.G. , Tamura N. , Gudmundsson M.T. 
Published: February 2024

Abstract
Characterization of 2017 drill core samples from Surtsey, an oceanic island produced by 1963–1967 eruptions in the offshore extension of Iceland's east rift zone, reveals highly heterogeneous microstructural, physical, and mechanical properties in subaerial, submarine, and subseafloor basaltic deposits. The connected porosity varies from 42% in weakly consolidated lapilli tuff in a submarine inflow zone to 21% in strongly lithified lapilli tuff in upper subseafloor deposits near the explosively excavated conduit. Permeability, however, varies over six orders of magnitude, from 10−18 m2 to 10−13 m2. Uniaxial compressive strength, P-wave velocity, and thermal conductivity are also highly variable: 10–70 MPa, 1.48–3.74 km·s−1, and 0.472–0.862 W·m−1·K−1, respectively. Synchrotron X-ray microdiffraction analyses integrated with major-element geochemistry and quantitative X-ray powder diffraction analyses describe the initial alteration of fresh glass, incipient consolidation of a fine-ash matrix, and partial closure of pores with mineral cements. Permeability, micromechanical, and thermal property modeling highlight how porosity and pore size in eruptive fabrics—modified through diverse cementing microstructures—influence the physical properties of the pyroclastic deposits. Borehole temperatures, 25–141 °C (measured from 1980 to 2018), do not directly correlate with rock strength properties; rather, the abundance and consolidation of a binding fine-ash matrix appears to be a primary factor. Analytical results integrated with archival data from 1979 drill core samples provide reference parameters for geophysical and heat transfer studies, the physical characteristics of pyroclastic deposits that lithify on a decadal scale, and the stability and survival of oceanic islands over time.