bluuebunny/crossref_metadata_2025_split huggingface dataset:
Friction Assessment in Hot Forging Operations Using Large-Scale Ring Compression Test
Authors: Gomez Diego , Ledesma Elias , Hino Ryutaro , Hamasaki Hiroshi , Aguilera Eduardo , Ruiz Ismael 
Published: January 2022

Abstract
The ring compression test is the most extended experiment for friction characterization in metal forming processes. However, these experiments are commonly carried out under laboratory environments with small specimens and highly controlled conditions, which may not accurately represent the industrial forging operations. For instance, a small size specimen does not provide enough surface area for the oxide scale formation and heat transfer, and these phenomena are critical in industrial processes. Then, friction characterization results are more accurate by using large-size specimens. In this paper, friction was determined by reverse engineering, using the commercial finite element (FE) code QForm, which is a commercial code for specific metal forming applications. Finite element models were adjusted considering both the final ring dimensions as well as the load-stroke during the entire experiment.
The design of experiments (DOE) matrix includes different factors and levels such as temperature, deformation speed, and high reduction. The temperatures were 900, 1100, and 1200 °C, the deformation speeds were 20, 80, and 150 mm/s, and the degree of deformations were 40, 60, and 80% in high reduction. The experiments were conducted to determine the friction in an actual crankshaft’s forging process. To determine that, ring specimens were done in a servo-hydraulic press, using compression plates made with the same material, thermal treatment, and surface coating as actual forging dies used in the crankshaft pre-forming operation. The temperature effect was higher than the deformation speed; however, these two factors have a strong interaction effect. On the other hand, from the FE models’ results, it was confirmed that the inner diameter reduction is highly sensitive to the coefficient of friction. However, the load-stroke behavior is less sensitive to friction changes, although it varies when different friction models are used.
Surface Finishing and Electroless Nickel Plating of Additively Manufactured (AM) Metal Components
Authors: Demisse Wondwosen , Mutunga Eva , Klein Kate , Rice Lucas , Tyagi Pawan 
Published: January 2022

Abstract
This study investigates the application of electroless nickel deposition on additively manufactured stainless steel samples. Current additive manufacturing (AM) technologies produce metal components with a rough surface. Rough surfaces generally exhibit fatigue characteristics, increasing the probability of initiating a crack or fracture to the printed part. For this reason, the direct use of as-produced parts in a finished product cannot be actualized, which presents a challenge. Post-processing of the AM parts is therefore required to smoothen the surface. This study analyzes chempolish (CP) and electropolish (EP) surface finishing techniques for post-processing AM stainless steel components CP has a great advantage in creating uniform, smooth surfaces regardless of size or part geometry EP creates an extremely smooth surface, which reduces the surface roughness to the sub-micrometer level.
In this study, we also investigate nickel deposition on EP, CP, and as-built AM components using electroless nickel solutions. Electroless nickel plating is a method of alloy treatment designed to increase manufactured component’s hardness and surface resistance to the unrelenting environment. The electroless nickel plating process is more straightforward than its counterpart electroplating. We use low-phosphorus (2–5% P), medium-phosphorus (6–9% P), and high-phosphorus (10–13% P). These Ni deposition experiments were optimized using the L9 Taguchi design of experiments (TDOE), which compromises the prosperous content in the solution, surface finish, plane of the geometry, and bath temperature. The pre- and post-processed surface of the AM parts was characterized by KEYENCE Digital MicroscopeVHX-7000 and Phenom XL Desktop SEM. The experimental results show that electroless nickel deposition produces uniform Ni coating on the additively manufactured components up to 20 μm per hour. Mechanical properties of as-built and Ni coated AM samples were analyzed by applying a standard 10 N scratch test. Nickel coated AM samples were up to two times scratch resistant compared to the as-built samples. This study suggests electroless nickel plating is a robust viable option for surface hardening and finishing AM components for various applications and operating conditions.
Image-Guided Multi-Response Modeling and Characterization of Design Defects in Metal Additive Manufacturing
Authors: Imani Farhad , Khanzadeh Mojtaba 
Published: January 2022

Abstract
The capability of metal additive manufacturing (AM) to produce parts with complex geometries manifests its potential to revolutionize manufacturing. However, the presence of heterogeneous defects even under optimized part design and processing conditions imposes critical barriers towards scaling metal AM to production environments. The recent advancement in imaging technology leads to a data-rich environment in AM and provides a unique opportunity to enhance understanding of design-quality interactions. However, the state-of-the-art image-guided methodologies focus on the characterization of the individual defect and are less concerned about transferring knowledge across heterogeneous defects to improve modeling and prediction ability. This study introduces a novel data-driven methodology to simultaneously quantify interactions between design parameters (e.g., orientation, thickness, and height) and heterogeneous defects (e.g., geometry distortion, discontinuity, and porosity) in the metallic AM build. A real-world case study on complex thin wall structures is evaluated with the single-response characterization models. Experimental results show average improvement of 64.8%, 70.4%, 73.3% in RMSE in comparison with single response model with inducing percentage u = 0.25, 0.5, and 0.75, respectively. The proposed model enables providing practitioners with a guideline to understand multimodal defects interrelation and fabrication of thin walls with minimal defects.
Numerical Simulation of Three-Dimensional Ocean Wave
Authors: Zhang Liting , Wang Xiuling 
Published: January 2022

Abstract
At present, caused by a large amount of wave energy resources and huge energy capacity, the development and utilization of wave energy have come to be an essential development focus of wave energy manufacturing. The purpose of this research is to simulate the ocean in an offshore environment. A three-dimensional Computational Fluid Dynamics (CFD) model was used to analyze the propagation of ocean waves. The Volume of Fluid (VOF) multiphase model and laminar model were used to analyze wave propagation in offshore conditions. Function Methodology and Mobile Methodology were implemented by applying User Defined Function (UDF) code which characterizes transient velocity profile. The parametric study was performed to analyze how velocity and amplitude change. The models were first validated by comparing them with previous analytical wave solutions. To prevent the reflection of the wave, a damping term was added by using User Define Function to define the viscosity of the water phase.
Controlling the Dynamics of a Quadratic Oscillator Using Infinite-Equilibrium
Authors: Xing Siyuan , Luo Albert C. J. 
Published: January 2022

Abstract
Dynamical systems with infinite-equilibria have been of great interest in recent years. The infinite-equilibrium can establish a flow barrier in phase space for control applications. For such a reason, a new method is proposed for controlling the dynamics of a quadratic oscillator by constructing an infinite-equilibrium through a feedback law. The local and global analysis of the unperturbed control system is presented, and the behaviors of the control system under disturbance is studied numerically. With the knowledge of disturbance, the control system can achieve bounded-input-bounded-output stability for any disturbance. Without the knowledge of disturbance, the control system can drive the flow to an equilibrium only for weak disturbance.
On the Vibration Transfer Characteristics From the Seat of the Vehicle to the Occupant
Authors: Morisaki Ryoma , Terashima Osamu , Kinoshita Fumiya , Touyama Hideaki 
Published: January 2022

Abstract
In this study, we aimed to achieve a human-adaptive vibration design in a vehicle cabin based on the sensory characteristics of the passengers. To this end, the psychological stress of the passengers as a result of the vibration of the seats in a commercial vehicle was studied. As an initial step, the vibrational acceleration of the seat was measured and its modal analysis was performed. We measured 22 points and 10 points of vibrational acceleration in three directions (vertical, longitudinal, and lateral) of the seat and its occupant, respectively, in a commercial vehicle. We then performed a modal analysis with the obtained data. The results show that the seat had four distinct vibrational modes in the idle state: vertical, horizontal, folding, and rising. The amplitude of the folding mode vibration was 24 Hz, which was consistent with the second-order vibration of the vehicle’s engine. This was the largest vibration of the seat. We also measured the brain and pulse waves of the seat’s occupant to estimate the psychological stress caused by the seat vibration. The results show that psychological stress can be estimated using brain waves. However, pulse waves were not suitable for estimating the psychological stress of the occupant owing to the negative influence of the noise caused by the engine on such waves. We also found that the sensitivity of the occupant to seat vibration can be estimated from the results of spectral analysis of the occupant’s gravity center.
Reinforcement Learning on Modular Robots Using Real-Time Decentralized Deconfliction in a Warehouse Environment
Authors: Sayed Andres , Scales Sara , Fox Austin , Stone Jafar , Crews Steven 
Published: January 2022

Abstract
This work seeks to incorporate existing methodologies for controlling and localizing robotic hardware of different capabilities in order to create an autonomous system of robots to move deliverables within an established environment. The system utilizes modular designs to employ rapid prototyping of different robotic capabilities highlighting the adaptability of this methodology. A high-level task manager centrally assigns priorities to each deliverable, and, through decentralized planning, the robots deconflict with one another during execution. Through the adoption of reinforcement learning techniques, our robots create individual path plans that adapt to both static and dynamic obstacles in real time. Contrasting other works that manage robotic systems in a predetermined and fixed environment, we demonstrate a single, simplified approach that can control and localize modular robots simultaneously in any given setting, to include warehouses and factories. This work utilizes the Robotic Operating System (ROS) to communicate between multiple robots of various capabilities and a single task manager, synchronizing autonomous movement and avoiding other tracked objects.
Crack Propagation and Fracture Toughness of Additively Manufactured Polymers
Authors: Pulok Mohammad Khairul Habib , Rahman M. Shafiqur , Chakravarty Uttam K. 
Published: January 2022

Abstract
Additive manufacturing (AM) technologies are catching the interest day by day due to their ability to produce very complex shapes or geometries. Investigating the fracture and fatigue behavior of additively manufactured parts are essential not only to understand their mechanical response but also to predict and prevent their failure. In this study, fracture and fatigue properties of additively manufactured polymers are investigated experimentally combining the servohydraulic material testing system (MTS 810) and the three-dimensional digital image correlation technology. The polymers used for the analysis are acrylonitrile styrene acrylate (ASA) and Onyx, which are readily available and more prevalent in AM applications. Both notched (i.e., pre-cracked) and unnotched specimens are printed in the edge and flat orientations by the fused deposition modeling printer in the shape of the standard ASTM sub-size flat dogbone structure. The tensile strain is studied ahead of the crack formation, and the crack propagation is observed in the photos obtained from the digital image correlation system. A finite element model of similar contemplation is generated for the validation and extended results. Results show that the orientation of manufacturing has a noticeable effect on the failure of the specimen. In the unnotched specimens, the crack occurs near the neck due to a high-stress concentration. Results for the high cycle fatigue test indicate that fatigue life decreases as the load increases for all types of specimens.
Acoustic Emission Detection and Signal Source Analysis of Boiler Water Wall Tube
Authors: Yuan Yilin , Shen Gongtian , Shen Yongna , Zhang Junjiao , Zhang Wenjun , Wan Qiang 
Published: January 2022

Abstract
This article introduces the entire process of acoustic emission detection of boiler water wall tubes. Due to the large curvature of the furnace tube surface, the sensor can only be installed in the area of the connecting plate between the furnace tubes, resulting in serious lateral attenuation. The distance between adjacent sensors in the lateral direction should be controlled within 40cm, but the longitudinal sensor can accept acoustic emission signals within the range of at least 80cm. Many acoustic emission positioning sources were found during the loading process. According to the standard of NB/T 47013.9-2012 “Nondestructive testing of pressure equipment Part 9: Acoustic emission testing”, the acoustic emission positioning sources were evaluated and classified. As a result, these signal sources are neither noise signals nor from crack propagation.
Enhancing Access to Water in Mexico City and Its Peri-Urban Area Through User Centered Design
Authors: Negrete Rojas David , Rodriguez-Tenorio J. Carlos , Ramos Álvarez Adrielly Nahomeé , Ramirez-Reivich Alejandro C. , Corona-Lira Ma. Pilar , Borja Vicente , Soler Anguiano Francisca Irene 
Published: January 2022

Abstract
Lack of water in Mexico City and its peri-urban area has been an increasingly worrying matter in the last few years and has been addressed through multiple government and NGO initiatives such as supplemental delivery via water trucks, rainwater harvesting, intermittence in water services and pipeline network maintenance. However, the rapid and unstructured development of the urban spot has exacerbated the problem, rendering these solutions ineffective.
Due to the complexity of the problem, solutions may be more impactful if they focus on fixing or creating effective interactions among the elements of the system — interactions in which the main element is the user. This paper presents a design proposal created from the observations made in Mexico City. Design Thinking was used by understanding the users’ needs and the interactions between the agents through three main phases: Approach and definition of the problem, Prototyping stage and Final proposal explanation.
The proposal and research results could be used and extrapolated to other cities and communities around the world, as water availability and quality are a global challenge and can be tackled in similar ways.
Kinetic Study of Nitric Oxide Formation at Atmospheric and High-Pressure Conditions for Different Primary Gaseous Fuels
Authors: Alam Fahd 
Published: January 2022

Abstract
Several recent detailed chemical kinetic models have been computationally investigated to assess the predictive competency of nitrogen oxides for gaseous low carbon number fuels. The objective is to understand how the recent models perform in predicting nitric oxide (NO) emissions at atmospheric and high-pressure including rich flames. Three different detailed kinetic models are considered for this assessment. For kinetic analysis, we employed one-dimensional laminar premixed flame (LFS) calculations using kinetic tool Cantera (v2.4) against measurements of laminar flame speed and NO speciation. The study is conducted at atmospheric and higher pressure (10, 14.6 atm) for varying equivalence ratios. In general, the kinetic models satisfactorily reproduced the LFS data. For NO prediction, acceptable emulation of measured data is observed at 1 atm for lean to slightly rich flames (Φ = 0.5–1.05), while greater discrepancies emerge at the rich flame conditions. At higher pressure, significant underprediction are also observed across for all three models. We found that prediction discrepancies at the rich mixtures are primarily linked to the prompt-NO pathways. Furthermore, rate of production analysis manifests that a consensus for the main reaction channels for NO at rich flames is yet to be established for these recent models.
Graphene Oxide / Nanodiamond Nanocomposites Characterized via Particle Dispersion and Micro- and Nanoscale Mechanical Properties
Authors: Abdelrahman Mustafa , Jewell Slade C. , Elbella Abdalla , Timpe Shannon J. 
Published: January 2022

Abstract
Polystyrene matrix nanocomposites were formulated using a custom nano particle consisting of nanodiamond covalently bonded to graphene oxide. Dispersion and mechanical property results for the nano composite are compared to those results for the neat polymer as well as for a nanocomposite infused with graphene oxide only. Dynamic light scattering was performed to determine the size of particles and the results showed that the custom nanoparticle reduced agglomeration by about 50% as compared to the graphene oxide alone. Microscale Vickers hardness testing revealed that neat polymer as well as the two nanocomposite samples all have similar hardness while nanoscale atomic force microscopy revealed that the neat polymer samples have the highest stiffness on average and the custom nanoparticle composite samples have the lowest stiffness. This difference in mechanical behavior with scale is attributed to local defects at the particle/matrix interface.
Integration-Free Frameworks for Exploring Strain Energy Density in Rubber-Like Elasticity
Authors: Akbari Ramin , Dargazany Roozbeh 
Published: January 2022

Abstract
Elastomers have been an active field of research during the past years for their extensive use in the industry. They are characterized by their unique hyper-elastic behavior, which can recover from a large amount of deformation. Constitutive models in rubber-like elasticity are essentially classified into 1) phenomenological and 2) physical-based models. The phenomenological models are based on direct experimental observation. Contrarily, Physical-based models come with a mathematical origin and employ physical hypotheses to describe a network of polymeric chains. As outlined in the literature, the accuracy of structure-based models has fallen behind the phenomenological models, despite their physical justification. The reasons for this unexpected fact lie in the simplified and superfluous assumptions that exist in the derivation of a closed-form expression for formulating material behavior. Moreover, physical-based models are calibrated through a nonlinear optimization schemes that, in essence, come with uncertainty. This uncertainty can be more affected by the complexity of the model. In this paper, we exploit an inverse approach to improve the accuracy of physically motivated models. To this end, We hold the virgin postulation in these models by considering the strain energy function in terms of two state variables that have been hypothesized to correspond to the kinetics of polymeric chains. Accordingly, we utilize B-spline interpolation to shift the unknown core functions of the strain energy potential to the macro-scale. Following this, we define a loss function based on the experimental data which is the macroscopic stress and use the simple linear least-square technique to determine these functions. In this way, we converge to a linear system of equations that is easy to solve and gives the best possible fit with data. Hence, In this numerical framework, we avoid unnecessary assumptions as far as possible and also nonlinear optimization for constitutive modeling. Finally, we compare the performance of the proposed methods with well-known models in the literature.
A Multiobjective Optimization Based Approach for Producing Manufacturable Structures From Topology Optimized Designs
Authors: Cerda Michael , Hamel Josh 
Published: January 2022

Abstract
The drive to produce low-cost structural designs that also have excellent engineering performance has led to a rise in the use of topology optimization (TO) methods. As a result, many commercially available computer aided design (CAD) software packages now include TO capabilities. Topology optimization can produce designs with superior performance by optimally allocating a budget of material within a given design domain, but the geometric complexity associated with many TO generated solutions makes realizing these designs via traditional (e.g. subtractive) manufacturing processes quite challenging. Additive manufacturing (AM) processes can effectively realize TO generated designs, but AM is not yet a universally acceptable manufacturing option for many applications. This paper presents the details of a more generally applicable design framework for using commercially available TO tools and an iterative procedure to create structurally optimized designs that are also manufacturable. This iterative process uses a TO solution to a structural design problem generated by a commercial CAD package as a target solution, and then successively adds optimally sized traditionally manufacturable features to the original structure until the engineering performance of the component is as close to the TO generated target design as possible in a multiobjective sense. This approach was tested on a two-dimensional structural design case study to demonstrate its implementation, effectiveness, and general applicability to wide variety of structural design problems.
Development of an Origami-Inspired Robot Using Self-Folding Technique
Authors: Shin Minchul 
Published: January 2022

Abstract
This report is about a self-folding origami-inspired robot that was created using a layer of paper, PVC film and 3D printed mechanism. Its inexpensive materials and rapid production allow the robot to have benefits and great potential in conditions where the robot needs to be disposable and can be mass produced. This report presents the principles of controlling the angle of paper folding, transporting kinetic energy from the energy source to the legs. This robot can carry, push, and pull each of 155.28%, 48.03%, and 58.39% of the weight of the whole system.
Distance/Online Engineering Education During and After COVID-19: Graduate Teaching Assistant’s Perspective
Authors: Kumar Vishnu 
Published: January 2022

Abstract
The COVID-19 pandemic has forced universities across the globe to switch to distance/online mode of teaching since Spring 2020. The engineering college teaching community including graduate teaching assistants were severely affected by this change. Even though numerous articles cite a variety of strategies for online teaching for full time instructors, it has been identified that there are limited resources tailor made for graduate students who are teaching engineering classes. This article tries to bridge this gap by exploring some strategies for graduate teaching assistants to help them prepare for online classes and overcome the challenges posed by online/distance education from a graduate student’s experience and perspective.