bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of a Solenoid Magnetic Field and an Electromagnet Magnetic Field on the Turbulent Flow and Heat Transfer of Conductive Gases in Circular Tubes
Authors: Zhao Qijin , Mao Baoquan , Bai Xianghua 
Published: February 2023

Abstract
A magnetic field can interact with a conductive fluid to form a magnetohydrodynamic effect, which can change the flow and heat transfer characteristics of the fluid. This introduces broad application prospects for magnetic field control of conductive gases in tubes, which is useful for thrust control of aero-engine nozzles, energy control of magnetohydrodynamic power generation channels, and anti-ablation of high-temperature tube walls. In this study, distributions of parameters, including the induced current, the electromagnetic force, and the Joule heat, in circular tubes under a solenoid magnetic field and an electromagnet magnetic field, are obtained and variations in the flow and heat transfer characteristics of conductive gases are analyzed through numerical simulations. The research results show that an applied solenoid magnetic field suppresses the turbulence and heat transfer of a conductive gas to a small extent, and that the suppression effect is isotropic. However, an applied electromagnet magnetic field significantly suppresses the turbulence and heat transfer of the conductive gas, and the suppression effect is anisotropic. Within a certain range of Hartmann number (Ha), the average Nusselt number at the tube wall decreases with increases in the Ha of the electromagnet magnetic field.
Identification of Flaws and Assessment of Mechanical Properties in Additively Manufactured Titanium Parts Using Acoustic Resonance Ultrasound Spectroscopy (RUS)
Authors: Taheri Hossein , Williams Caleb , Krenek Russell , Weaver Gregory , Taheri Mohammad 
Published: February 2023

Abstract
Additive manufacturing (AM) techniques are becoming accepted as routine in many industrial fields that include aerospace applications. This ramp up in manufacturing has highlighted a fundamental need for innovative nondestructive testing (NDT) methodologies for AM inspection and qualification purposes. Resonance Ultrasound Spectroscopy (RUS) is beginning to be applied as an innovative NDT inspection technique for AM components to obtain insights from the parts’ structural integrity and because it correlates to mechanical properties. RUS is used to understand sensitivity to detecting internal flaws, resulting in lower than expected failure resistance or fatigue life. Multiple test bar batches using the Ti6Al4V alloy were fabricated by powder bed fusion (PBF) AM technique at different processing conditions. RUS and destructive tests, including tensile and fatigue tests, based on ASTM standards are performed in order to evaluate the mechanical properties and tensile and fatigue strength of the parts. Finally, metallography experiments revealed the microstructure of the parts. The goal of correlation analysis is to establish the defect-NDT-property relationship for the Ti6Al4V by showing the strength and significance of the relationship between the testing data and the properties of the samples. Results show that RUS is a reliable and capable NDT technique to acquire rapid information for this purpose. This information is crucial for expanding the production and application of AM components while making sure that the mechanical properties, their structural integrity, and part safety satisfy the requirement of the lifetime operation.
Experimental Investigation of the Robustness of Bulk Metallic Glass-Based Tooling for Microinjection Molding
Authors: Almalki Ahmed , Rajhi Ali , Noor Hussam , Kundu Animesh , Coulter John 
Published: February 2023

Abstract
The primary objective of this research was to experimentally investigate the robustness of a commercially available zirconium-based bulk metallic glass material (Zr-based BMG) for microinjection molding (μIM) tooling. The focused ion beam (FIB) direct milling process was utilized to fabricate microfeatures onto two BMG-based mold inserts.
Uncoated and Ti-coated inserts were inspected through molding cycles utilizing SEM. Additionally, TPU molded samples were characterized to quantify the replication quality of the inserts through molding cycles. This is to understand the polymer melt effect of the tooling during molding conditions.
The uncoated BMG insert was utilized for more than 1000 molding cycles regardless of the potential crystallization. No signs of any crack initiation were observed in any part of the BMG insert. Through molding process, the replication quality degraded due to the polymer adhesion to the microcavity base.
In the case of the coated BMG insert, the coating could not withstand the high ejection force during demolding stage. The adhesion between the coating and the BMG surface was insufficient to survive molding conditions. This resulted in disintegrated coating that was bonded into molded samples.
Benefit of Optimal Actuator Selection – A Comparative Study
Authors: Hanna Pavlos , Carmichael Marc , Clemon Lee 
Published: February 2023

Abstract
Actuators are a vital component, and often the limiting factor in robotics and robotic-related applications like humanoids, exoskeletons, prosthetics and orthosis. Actuator selection is critical due to system design flow-on effects including weight, energy consumption and form factor. A designer’s challenge is often to optimize the actuator to minimize size or weight and meet the performance specifications usually with trade-offs. This paper investigates the design impacts of selecting more suited actuators on the system through a representative humanoid configuration performing a task. It also looks at variations based on the scale of the humanoid using human anthropometric data for variations in limb lengths. The torques and speeds required at each joint to complete the task is simulated and the system design is updated to keep a constant member stress across all designs. The total energy and weight are calculated and used to compare actuator selection impacts. By knowing the extent of the flow-on effects actuator selection has on a configuration, and how this effect scales, designers are able to determine what investment should be allocated to locating the ideal actuator for their task.
Bolted Lap Joint Monitoring Using Ultrasonic Guided Waves Considering Temperature Variations
Authors: Peng Xuezhi , Shen Yanfeng 
Published: February 2023

Abstract
This paper presents the numerical investigation of ultrasonic guided waves for bolted lap joint Structural Health Monitoring (SHM), considering temperature variations. It first systematically discusses the mechanisms behind the linear and nonlinear ultrasonic techniques for bolt loosening detection. Afterwards, a general Finite Element Model (FEM) of a bolted structure was established to observe and verify the influence of the change of bolt pre-tightening force on the linear and nonlinear characteristics of ultrasonic guided waves. In order to further study the effect of temperature variation on the sensing signals, the structure is subjected to various levels of thermal loads. This study examines the temperature influence on both linear and nonlinear signal features, such as the transmitted wave energy and the nonlinearity of waveforms. Simulation results show that an increment in temperature can cause partial detachment of the interface between two lap joint components in the structure, resulting in a decrease in both the linear energy and the degree of nonlinear higher-order harmonics. The paper finishes with concluding remarks and suggestions for future work.
Investigation of Mechanical Properties of Combinatorial Ti-Cu Film Using MD Simulation With Neural Network Potential
Authors: Miyagawa Takeru , Sakai Yugo , Yonezu Akio , Mori Kazuki , Kato Nobuhiko , Ishibashi Keiji 
Published: February 2023

Abstract
Combinatorial approach is a prominent method to synthesize samples with atomic composition gradients, which enables the high-throughput discovery of new materials. Titanium-copper (Ti-Cu) alloy is widely used in electronic devices because of its excellent mechanical properties such as stress relaxation resistance, bond formality, and workability. By synthesizing Ti-Cu thin film with combinatorial approach, the mechanical property may be improved, leading to a new application. Molecular Dynamics (MD) simulation is a powerful tool to predict mechanical property, but it requires interatomic potentials to depict the movements of atoms. Because of the complex structures of Ti-Cu thin film synthesized by combinatorial approach, the creation of interatomic potentials is a difficult and time-consuming process. Therefore, in this study, a neural network (NN) based method to create interatomic potentials is developed, which are referred to as neural network potentials (NNPs). It is found that NNP can accurately reproduce the energies and forces calculated by Ab initio molecular dynamics (AIMD) simulations. Finally, using MD simulations with developed NNP, the mechanism of mechanical properties is investigated from the perspective of atomic scales.
Numerical Study of Inclination Effect on a Flat-Place Direct Absorption With Water-Nanofluid Mixtures in Summer and Winter Conditions
Authors: Buonomo Bernardo , Cardillo Fabio , Chirico Pietro , Manca Oronzio , Nardini Sergio , Russo Giovanna , Scapaticci Angela , Vicidomini Ivan 
Published: February 2023

Abstract
In this work, a computational study on two-dimensional forced convection inside a volumetric solar collector based on a nanofluid with water and nanocarbon horns is carried out in steady state regime. A surface heat transfer from the upper wall of the solar collector toward the external ambient is present. The analysis is accomplished with governing equations assuming the single-phase flow model for the nanofluid mixture. The evaluation of heat transfer in the participating media due to the local absorption of nanoparticles is obtained employing the non-grey discrete ordinates method. The finite volume method is employed to find the solution and the simulations are obtained using ANSYS-FLUENT code. The analysis is accomplished to estimate the solar collector behaviors as a function of the inclination angle under different conditions in summer and winter regimes for residential use site in Aversa (Italy). The analysis allows to evaluate the thermal and fluid dynamic behaviors of the solar collector with an inclination angle from 0 to 90 degrees. Temperature and velocity profiles as well as temperature fields inside the channel are reported for different inclination angles, solar radiations and nanoparticle volumetric concentrations.
Structure-Resistance Relationship of 3D Printed Electrically Conductive Woodpile-Structured Metamaterials
Authors: Vasilyan Hayk , Lapuz Oginne , Susantyoko Rahmat Agung , Almheiri Ahmad , Alyammahi Mozah 
Published: February 2023

Abstract
This work proposes metamaterial with a woodpile arrangement constructed of its electrically conductive constituent material. Electromechanical response of woodpile structured metamaterials, when compressed, was experimentally studied. Specifically, when they are compressed in the stacking direction, with struts symmetrically staggered in alternating layers. Additive manufacturing has enabled the fabrication of metamaterials with tunable electromechanical properties. Herein, the structure-resistance relationship was established as a function of microstructural parameters described by the geometry of the repetitive elements of the structure, such as characteristic diameter, length, or thickness. The relationship also can be expressed in the form of relative density. We found that conductive metamaterials with staggered-woodpile architecture could effectively manipulate the electrical properties when compressed due to their local bending motions and contact between members. Such metamaterials could have high sensitivity as well as high stiffness – low sensitivity by controlling the spacing and diameter of struts. The findings from this study suggest that structured woodpile metamaterials are promising as strain sensors when mechanically implied or human-induced forces are present. When loaded at ∼3 % compressive strain, the materials appeared to have a typical transition phase from high to low resistance.
Numerical and Experimental Investigation of Rheodrop Technology
Authors: Alqosaibi Khalid , Alemmrani Mohammed , Almalki Ahmed , Duhduh Alaauldeen , Coulter John 
Published: February 2023

Abstract
A novel invention to advanced hot runner-based injection molding called Rheodrop technology is introduced. The technology allows control over the melt rheology inside the hot drops during/between injection molding cycles. The concept is to rotate the valve pin inside the hot drop to apply a controlled shear rate to the polymer melt. Doing so eliminated the incomplete filling defects associated with molding thin-walled parts and allowed processing at a lower melt temperature. The applied shear stress by Rheodrop technology was investigated utilizing ANSYS fluent software. The maximum shear stress that the polymer gets exposed to during the injection molding cycle was specified using Moldflow software. The results showed that the Rheodrop applies less shear stress than what the polymer gets exposed to during the injection molding cycle. Thus, utilizing Rheodrop does not cause additional damage to the polymer melt. Rheometric analyses were performed to investigate the polymer degradation for ABS. The reduction rate of viscosity was the same for samples that were injection molded conventionally and samples that were molded using Rheodrop technology.
A Note on Probability Quantification for Protective System Efficacy Analysis: Stochastic Dynamics, Information Flow, and Initiating Event Arrival Times
Authors: Wortman Martin , Kee Ernest , Kannan Pranav 
Published: February 2023

Abstract
Probability Quantification (PQ) predictions of the efficacy of safety-critical protective systems is challenging. Yet, the popularity of PQ methodologies such as, Probabilistic Risk Assessment (PRA), Quantitative Risk Analysis (QRA) and Probabilistic Safety Analysis (PSA), is growing and can now be found written into regulatory rules. PQ in predictive modeling is attractive because of its grounding in probability theory and focus on numerical results.1 But, certain important safety related events are not probability-measurable which is problematic for risk-analytic methodologies that rely on PQ computations. Herein, we identify why the dynamics of available information play an essential role in governing the fidelity of PQ, and why PQ in the analysis of safety-critical protective systems is limited by the unmeasurability of certain critical events.2 We provide an historical example that provides a practical context for our observations. Finally we discuss the implications of measurability for regulatory decision-making governed by recent nuclear industry legislation advocating increased use of risk informed, performance-based regulation for advanced reactor licensing.3
A STEM Roadmap for Pre-Collegiate Engineering Students
Authors: Gharib Ali , Alyafei Nayef 
Published: February 2023

Abstract
In this paper, a comprehensive roadmap is presented that aims to provide an accessible and convenient resource for pre-collegiate students who are interested in science, technology, engineering, and mathematics (STEM) fields. The presented roadmap will be an effective guide to the students who are wishing to pursue STEM education independently in preparation for further studies or for personal development, but unsure of the specific activities and skills they require to kickstart them. The road map will also serve as a practical guide for teachers, counselors, and caretakers to guide and inform students interested in STEM tracks. This roadmap covers various recommended activities and courses that impart students with the necessary knowledge, experiences, and skills that are central in STEM studies and careers. An extensive literature review is conducted on various STEM programs from all around the globe that have a high impact on students in their respective fields, along with a recommended grade level for participation in said course/activity. Presented by this paper in each overview section are the individual advantages of each program with reference to skill acquisition, networking opportunities and even possible credits or accreditation detailed. Most of the presented programs are accessible online or in schools and STEM centers in most regions. Students who follow and complete this road map will not only be pre-equipped with the engineering knowledge before joining college but also will improve their position as a candidate for undergraduate or advanced level course selection.
Research on a New Analysis Method of Traction Performance for Variable-Diameter Wheels
Authors: Zeng Wen , Jiang Hui , Xu Guoyan , Gao Feng 
Published: February 2023

Abstract
Folded variable-diameter wheels used in planetary rovers can save spacecraft volume. Moreover, they can be expanded to improve their mobility on soft soil. However, only a single wheel foot was considered in previous researches on wheel-terrain interaction, which may be inaccurate. Hence, the cycloid motion equations for an unfolded variable-diameter wheel were introduced to obtain the shear displacement of any point on a wheel foot. Then, determining wheel-soil interaction regions was transformed into geometric relationship analysis. Therefore, the simplified model with a single wheel foot was established. Consequently, the traction efficiency achieved the peak when the range of wheel slip rates was 0.15∼0.35. The results shown that increased wheel diameter improved wheel mobility. For a greater sinkage, with the superposition of simplified model, the detailed model based on multiple wheel feet was built. This model got closer to real interaction status. The finite element analysis (FEA) results for the rolling wheel on soft soil were consistent with the theoretical hypotheses. Overall, the simplified model is very efficient, however, the detailed model is more accurate, which provides theoretical references for the control of optimizing wheel mobility. Additionally, this new analysis method developed here can also be applied to other expandable wheels.
Forestry Crane Immersive User Interface for Control and Teleoperation
Authors: Pizzagalli Simone Luca , Bondarenko Yevhen , Baykara Baris Cem , Niidas Alar , Kuts Vladimir , Kerm Margus , Otto Tauno 
Published: February 2023

Abstract
Timber industry is one of the most relevant economic sectors in Estonia. Automatization of forestry management and harvesting processes optimization are realities also in this specific domain. As much as in other industrial fields adopting the Industry 4.0 paradigm and core technologies, forestry management, log harvesting and the wood processing industry make use of state-of-the-art sensors, Digital Twins and advanced interfaces for the operators. The latter include Extended Reality solutions and remote-control making use of immersive head mounted displays (HMD). This works presents an innovative system for hydraulic forestry crane teleoperation making use of HMD and wide-angle camera stream. The system hardware is installed locally while the software, integrated in Unity, supports the operator in using the crane’s native joysticks and controller for the log loading operations. Additional virtual user interface and controls are included in the immersive view and accessible through the same controls and joysticks.
Recycling of Campus Solid Wastes Into a Low-Cost Green Instructional Equipment
Authors: Galindo Ronald M. , Obiso Jun-Jun A. , Caladcad Aian Rey A. , Tibay Edgar U. 
Published: February 2023

Abstract
A common problem in some State Universities and Colleges (SUCs) in the Philippines is the accumulation of campus solid wastes. A popular approach to minimizing this problem is the application of 3Rs (Re-use, Recycle, Reduce). These 3Rs are used by Cebu Technological University-Main Campus at Cebu City, Philippines, to foster Green Technology and promote a circular economy. The application of 3Rs is very timely since some classrooms are still traditional with no complete instructional equipment and devices to fortify instructional delivery. Hence, this paper’s ultimate intention is to develop low-cost, portable, and green instructional equipment through 3Rs adoption. This paper uses the instructional equipment from reusable campus solid wastes like glass, wooden pallets, tree branches, and swivel wheels. This equipment is fully loaded with the instructional materials and devices needed in the teaching-learning process. With its portability, the teachers can quickly transfer between classrooms with the instructional loads. In functionality assessments, several tests were conducted, like the stress analysis test, drop test, and system quality evaluation. Test results suggest that this instructional equipment is beneficial for instructional delivery in developing SUCs in the Philippines. Moreover, the equipment may not be solely used for classroom instruction during face-to-face classes but also can be usable during online classes.
Investigation of Tube Sheet Joining Through Hydroforging Process
Authors: Memon Shabbir , Nikhare Chetan P. 
Published: February 2023

Abstract
Tube-to-sheet joint expansion has been successfully used in HVAC industry for many years to avail better heat exchange between tube and fins (sheet). Because this system transports fluids under pressure, joining tube and sheet in heat exchangers is critical for all processing industries. The tube-sheet connection’s joining strength is critical because it directly affects plant safety. Tube-to-sheet joint strength is measured in terms of residual contact stress between the tube’s outer surface and the sheet’s hole surfaces. The joint integrity is affected by several design parameters, including the type of material and the initial radial clearance. The tube can be either deformed with or without an internal fluid pressure to create a joint. A commonly used process to deform the tube is hydroforming. However, hydroforming mostly uses the high pressure to deform the cross-section without dominantly use of axial length of the tube. In contrast, another category where the dominant use of axial length of the tube material is used to deform the section is termed as a hydroforging process. The use of a plastic deformation technique in hydroforging joining technology eliminates some of the limitations of existing joining technologies. The sheet deforms more strongly than the tube after the expansion tool is retracted. As a result, the tube and sheet come into direct contact.
This method allows for the joining of dissimilar materials and is also environmentally friendly. Fastened joints, welded joints, and adhesive joints are all examples of methods of joining that are comparable to each other in terms of their advantages and disadvantages. In this paper a tube to sheet joint will be studied during the hydroforging process. While the tube is pressurized with low pressure, the axial force will be applied to buckle the tube outward and around sheet. In the second stage the buckling region was compressed to make a joint. Two setting will be studied: intermediate joint (named: mid joint) and end joint. For this work a two-dimensional (2D) axisymmetric finite element model will be developed. The axial compression to create a buckling/folding in the tube and later joining with the sheet were studied. The mechanics of the buckling/folding was analyzed during the axial compression. The stresses induced at the interface were studied and resulted.