bluuebunny/crossref_metadata_2025_split huggingface dataset:
Subsurface and At-Depth Interphase Characterization in Hygrothermal Aged Carbon Fiber Reinforced Polymer Matrix Composite
Authors: Yekani Fard Masoud , Raji Brian , Pankretz Heidi , Mester Jack , Pensky Alek 
Published: February 2021

Abstract
The interphase region between the carbon monofilament and epoxy matrix in Carbon Fiber Reinforced Polymer Composites (CFRPs) is immensely vital to transfer stress between carbon monofilament and bulk matrix material. To the best of the authors’ knowledge, no other research group has studied the interphase region at subsurface and at-depth levels on hygrothermal aged CFRPs. The composite samples were exposed to 60° C and 90% humidity for one and two years. Moisture absorptions were measured periodically to assess water gain in the material. The advanced Atomic Force Microscopy (AFM) based Peak Force Quantitative Nanomechanics Mapping Technique was used to study the physics of the interphase. PFQNM allows non-destructive and simultaneous capture of imaging and mechanical property data with nanometer resolution. The interphase thickness was increased with increased hygrothermal exposure time. The interphase surrounding carbon monofilaments exhibited nonuniform thickness, ranging from ∼85 to 95 nm in the subsurface level, and from ∼10 to 75 nm on the at-depth level. Aged samples showed a decrease in average surface roughness, likely due to swelling of the epoxy matrix caused by the moisture absorption. The water diffusion generally followed Fickian.
Local Hot Spots of Electric Water Pump Casing Over Various Pumping Loads
Authors: Kim Younghyeon , Choi Yoora , Yu Sangseok 
Published: February 2021

Abstract
The cooling system of an electric vehicle adopts an electric water pump. Since the lifespan of the battery is very sensitive to a very narrow temperature band, the cooling system provides key solutions. The electric water pump is a core component of the cooling system which satisfies performance and durability criteria. Since, a local hot spot of motor casing results in the degradation of motor lifespan, it is necessary to design the motor casing for effective heat rejection. In this study, two different motor casing designs are applied to reject the joule heating of the motor efficiently. The temperature distribution of each casing is investigated with an IR camera. The IR camera was used to identify the local hot spot where the heat was most generated in the pump. Since the joule heating is proportional to pump power, it is necessary to understand the operating characteristics of the electric water pump. The experimental apparatus includes a water reservoir, a bypass valve, pressure and temperature sensors, DAQ, and IR camera. The operating temperature is ranged from atmospheric temperature to 50°C. When the pump is operated with 25°C coolant, each experiment takes 1 hour for the steady-state conditions and maximum temperature up to 55 °C. Three different pump performance are investigated with two different pump casing. The coolant temperature is also changed from 25 °C to 50 °C. As a result, the local hot spot is strongly dependent to pump load and it is mainly observed near the cable connector. Since temperature distribution on the casing surface is also affected by local hot spots, it is necessary to optimize heat rejection by extended surface.
Design of a Real-Time Human-Robot Collaboration System Using Dynamic Gestures
Authors: Chen Haodong , Leu Ming C. , Tao Wenjin , Yin Zhaozheng 
Published: February 2021

Abstract
With the development of industrial automation and artificial intelligence, robotic systems are developing into an essential part of factory production, and the human-robot collaboration (HRC) becomes a new trend in the industrial field. In our previous work, ten dynamic gestures have been designed for communication between a human worker and a robot in manufacturing scenarios, and a dynamic gesture recognition model based on Convolutional Neural Networks (CNN) has been developed. Based on the model, this study aims to design and develop a new real-time HRC system based on multi-threading method and the CNN. This system enables the real-time interaction between a human worker and a robotic arm based on dynamic gestures. Firstly, a multi-threading architecture is constructed for high-speed operation and fast response while schedule more than one task at the same time. Next, A real-time dynamic gesture recognition algorithm is developed, where a human worker’s behavior and motion are continuously monitored and captured, and motion history images (MHIs) are generated in real-time. The generation of the MHIs and their identification using the classification model are synchronously accomplished. If a designated dynamic gesture is detected, it is immediately transmitted to the robotic arm to conduct a real-time response. A Graphic User Interface (GUI) for the integration of the proposed HRC system is developed for the visualization of the real-time motion history and classification results of the gesture identification. A series of actual collaboration experiments are carried out between a human worker and a six-degree-of-freedom (6 DOF) Comau industrial robot, and the experimental results show the feasibility and robustness of the proposed system.
Development of Prototype of Two Axis Gimbal-Type Platform in Underwater
Authors: Park Hoonmin , Lee Hyunjae , Ryu Hongryul , Kim Dongho , Kim Hyunsoo , Park Hyesoo , Lee Sangryong , Yi Hak 
Published: February 2021

Abstract
The Bottom-mounted ocean-observation platforms installed on the seabed have been used for marine environment analysis. The role of the observing platform is to collect precise observation data without human assistance. However, their working environment is very harsh so the typical device could not afford to provide easy accessibility during their working period. Existing bottom-mounted ocean-observation platforms have been difficult to collect continuous observation data. Therefore, this paper suggests a new ocean-observation platform for precise measurement of the marine environment. Suggested platform uses a PID control method to be applied for error compensation of each axis of gimbal. To verify the system performance, the experiment was carried out in the air with the external force applied to this system.
Aerodynamic and Vibration Analysis of the Morphing Wings of a Hypersonic Vehicle
Authors: Pulok Mohammad Khairul Habib , Chakravarty Uttam K. 
Published: February 2021

Abstract
Hypersonic vehicles are receiving great attention in recent years due to their high speed and long-range capabilities. The shock waves come into consideration as a propagating disturbance for any aircraft when it exceeds the speed of sound. Complex environment and flight requirements of the hypersonic vehicles are leading the researchers to focus on several design considerations. Adaptive shape deformation is one of the prospective areas among them which has an impact on thermal loading, global and local load factors, vehicle acceleration, total energy dissipation, and fuel consumption. The wings play a key role in the aerodynamic performances of a flying machine; therefore, the overall performance of the hypersonic vehicle can be improved by applying morphing technologies on the wing. Morphing can help with reducing wave drag, increasing lift-to-drag ratio as well as enhancing flight endurance, and extending the range for a hypersonic vehicle. In this study, the telescopic wing morphing profile is considered for the aerodynamics and vibration analysis. The experimental validations of the aerodynamics and vibration characteristics are conducted by a wind-tunnel experiment and a vibration-testing arrangement, respectively, using a small-scale model of the wing. The computational analysis of the aerodynamics and vibration characteristics of the morphing wings are conducted and compared. Thus, a comprehensive study including the comparison between morphing modes can establish a standard to choose the appropriate morphing technique for the hypersonic vehicles.
Forming Canonical 8D Data Clouds to Explore the Transient Dynamics of Physical Stiffened Plates: A Machine Learning Approach for Complex Mechanical Structures
Authors: Georgiou Ioannis T. 
Published: February 2021

Abstract
This work presents a data-driven explorative study of the physics of the dynamics of a physical structure of complicated geometry. The geometric complexity of the physical system renders the typical single sensor acceleration signal quite complicated for a physics interpretation. We need the spatial dimension to resolve the single sensory signal over its entire time horizon. Thus we are introducing the spatial dimension by the canonical eight-dimensional data cloud (Canonical 8D-Data Cloud) concept to build methods to explore the impact-induced free dynamics of physical complex mechanical structures. The complex structure in this study is a large scale aluminum alloy plate stiffened by a frame made of T-section beams. The Canonical 8D-Data Cloud is identified with the simultaneous acceleration measurements by eight piezoelectric sensors equally spaced and attached on the periphery of a circular material curve drawn on the uniform surface of the stiffened plate. The Data Cloud approach leads to a systematic exploration-discovery-quantification of uncertainty in this physical complex structure. It is found that considerable uncertainty is stemming from the sensitivity of transient dynamics on the parameters of space-time localized force pulses, the latter being used as a means to diagnose the presence of structural anomalies. The Data Cloud approach leads to aspects of machine learning such as reduced dynamics analytics of big sensory data by means of heavenly machine-assisted computations to carry out the unparalleled data reduction analysis enabled by the Advanced Proper Orthogonal Decomposition Transform. Emphasized is the connection between the characteristic geometric features of high-dimensional datasets as a whole, the Data Cloud, and the modal physics of the dynamics.
Data-Driven Methods for Detecting Traffic Jams in Vehicular Traffic Systems
Authors: Ghadami Amin , Doering Charles R. , Epureanu Bogdan I. 
Published: February 2021

Abstract
Ground vehicle traffic jams are a serious issue in today’s society. Despite advances in traffic flow management in recent years, predicting traffic jams is still a challenge. Recently, novel techniques have been developed in complex systems theory to enable forecasting emergent behaviors in dynamical systems. Forecasting methods have been developed based on exploiting the phenomenon of critical slowing down, which occurs in dynamical systems near certain types of bifurcations and phase transitions. Herein, we explore recently developed tools of tipping point forecasting in complex systems, namely early warning indicators and bifurcation forecasting methods, and investigate their application to predict traffic jams on roads. The measurements required for forecasting are recorded dynamical features of the system such as headways between cars in traffic or density of cars on road. Forecasting approaches are applied to simulated and experimental traffic flow conditions. Results show that one can successfully predict proximity to the critical point of congestion as well as traffic dynamics after this critical point using the proposed approaches. The methodologies presented can be used to analyze stability of traffic models and address challenges related to the complexity of traffic dynamics.
Teaching Creativity As a Method to Overcome Limitations in Design for Additive Manufacturing
Authors: Chekurov Sergei 
Published: February 2021

Abstract
This paper describes the challenges and solutions of modifying a normally contact-reliant Design for Additive Manufacturing teaching approach in view of the COVID-19 outbreak. The approach has been put into practice since 2014 in the form of a student assignment that does not provide a specific functional objective but asks students to invent a unique geometry that demonstrates the capabilities of additive manufacturing and manufacture it with an entry level material extrusion machine.
The students are asked to use their imaginations to develop an intricate geometry without first considering technical limitations of additive manufacturing. They are then asked to identify the issues with their designs and solve them, while modifying their original vision as little as possible. The goal of the approach is to teach students to identify the limitations of additive manufacturing and to overcome them with creativity when possible.
As physical iterative testing using an additive manufacturing machine is essential to the assignment, the outbreak of COVID-19 had a major influence on it. The paper describes how the assignment was adjusted in the spring of 2020 to meet the challenges of not being able to conduct contact teaching. Although the presented exceptional measures should be avoided as the primary way to educate students, they are shown to facilitate teaching Design for Additive Manufacturing with no access to machines. Notable designs developed by students in 2020 are provided as examples of the generated results.
Optimization of Plunger Injection Input for Die Casting Process
Authors: Qi Song , Takagi Yuto , Yano Ken'ichi , Kondo Tadao , Murakami Naoto , Ishikawa Takao 
Published: February 2021

Abstract
Die casting is adequate for mass production and has the advantage of being able to yield a complicated shape accurately. However, casting defects caused by plunger movement remain a problem. Velocity control of the plunger is very effective to avoid casting defects. Velocity control input is manually conducted by skilled workers because the analysis of molten metal is very difficult, and injection molding is performed at places in the mold where it is invisible. In this paper, Quid behavior and the amount of air entrainment caused by the movement of the die casting plunger are analyzed using computational Quid dynamics (CFD). The optimum velocity control input of the die casting plunger was calculated in order to reduce air entrainment and molten metal forerunning to prevent the occurrence of defects in the die casting product. Optimization was performed by a Genetic algorithm incorporating CFD simulator.
Development and Evaluation of an Infrared Heating System for Die Preheating
Authors: Maldonado Luis , Shi Carl , Vian Corey , Ostanek Jason 
Published: February 2021

Abstract
In this study, a high power infrared heater was implemented to preheat an H13 steel die used for high pressure die casting. The performance of the heating system was quantified experimentally by measuring die temperatures in various locations with embedded thermocouples. Heating time was reduced significantly by using a flat, stainless-steel reflector on one side of the heater. A numerical model was developed to simulate the infrared radiation heat transfer into the die. The model was validated against literature data and experimental results. The model was then used to evaluate different lamp configurations to obtain a more uniform heating distribution and to avoid hot spots on protruding surfaces. The validated model has proven to be useful in evaluating different lamp configurations tailored for specific die geometries or heating requirements.
Passive Impedance-Loaded Surface Acoustic Wave (SAW) Sensor for Soil Condition Monitoring
Authors: Chu Jian , Voiculescu Ioana , Dong Ziqian , Li Fang 
Published: February 2021

Abstract
This paper presents an innovative system to monitor the physical soil conditions needed for modern agriculture. The current technique to measure soil properties relies on taking samples from place to place and takes them for laboratory testing. To build up and monitor a data-based system for a large area, such a method is costly and time-consuming. This paper reported our recent work on the development of a passive impedance-loaded surface acoustic wave (SAW) sensor for a low-cost soil condition monitoring system. The SAW sensor will eventually be connected to an antenna and a impedance-based sensor for autonomous soil nutrient sensing. In this research, first, the coupling-of-modes (COM) analysis was performed to simulate the SAW device. The sensors were fabricated with E-beam lithography techniques and tested with different external load resistances. We investigated how the sensor signal changed with the external resistance loading. The experimental results were verified by comparing them with simulation results.
Biomechanical Analyses of Professional Ultramarathon Athletes: The Effect of Repeated Long Distances on the Gait Kinematic and Kinetics
Authors: Fontanili Luca , Milani Massimo , Montorsi Luca , Citarella Roberto 
Published: February 2021

Abstract
Constant monitoring of an athlete allows to foresee any injuries by acting on the dynamics of the movements. For runners, the conduct of a correct athletic gesture according to the athlete’s specific body biomechanics guarantees the minimization of non-accidental injury factors. For athletes who are engaged in endurance sports such as marathon runners, the long distances to which they are subjected increases the importance of this type of monitoring. This work reports the results of a study carried out on three IUTA (Italian Ultramarathon and Trail Association) athletes during a routine check carried out at a reference healthcare facility that takes care of their care. These athletes are all specialized in the 24-hour race in which they try to reach the most distance in this time. This type of effort can be made if the athlete undergoes an adequate training regime over long distances. The execution of the running pattern in such a repeated way can lead to the accentuation of postural and joint problems. It is therefore necessary to monitor the biomechanics parameters.
In this work, therefore, various gestures are analyzed to show potential movement deficits in order to act in advance on the running technique.
Multitier Digital Twin Approach for Agile Supply Chain Management
Authors: Shevtshenko Eduard , Mahmood Kashif , Karaulova Tatyana , Raji Ibrahim Oluwole 
Published: February 2021

Abstract
Multitier Digital Twin approach for agile supply chain management validated in the research lab. In the long run, the solution will ultimately help to reduce resources costs in production processes and throughput time of the supply chain. The Digital Twin approach can be applied in the manufacturing company and the supply chain and makes recommendations for making changes to the physical environment to meet the requirements of various specific orders. The Multitier Digital Twin approach is validated by modelling four tiers of Small and Medium Enterprise (SME) company: business processes, operations workflow processes and work cells operations. The simulation study is performed to evaluate the achieved results. The guidelines are developed to connect and integrate business process tier models with operations workflow and work cell tiers models. The authors defend that the current research will help to create new digital solutions to increase manufacturing flexibility by moving toward the company’s strategic goals directly from the offer preparation stage. The authors have validated the Digital Twin approach for agile supply chain management in the fields of manufacturing. Nevertheless, the proposed approach is adaptable to other fields also, whereas the focal player or project owner selects the best KPIs that support the implementation of the chosen strategy. The paper includes a feasibility case study for the approval of findings, where small and medium enterprise (SMEs) from the manufacturing field business processes are connected to manufacturing processes and work cell models to achieve a common strategic goal of the company.
Early Assessment of Posture Disorders Through Pre-Adolescent Monitoring: The Case of Volley Academy Modena
Authors: Fontanili Luca , Milani Massimo , Montorsi Luca , Citarella Roberto 
Published: February 2021

Abstract
The pre-adolescent age is basic in the beginning of the development of body kinematics. During this age the body structure needs to continuously search for stabilization due to the modification in body segment lengths. This behavior can evolve into incorrect postural attitudes that, if not properly treated, can lead to behaviors that are difficult to recover with advancing age. These incorrect attitudes require an accurate and early diagnosis that can be put in place by expert doctors and clinicians.
As well known, sporting activity in this age can help the development of proprioceptive apparatus and the musculoskeletal one. Volleyball is considered a complete sport thanks to the wide range of actions necessary for a match. Following this evaluation, it was decided to carry out a monitoring study of young volleyball players in what is one of the capitals of Italian volleyball, i.e. Modena.
To achieve this objective, in this work, 97 female volleyball players have been analyzed during their adolescent and pre-adolescent age. The study has the objective to collect data and design an exercise routine for the training to prevent postural problems. Finally, the data have been analyzed and the most representative ones have been reported in this paper.
Effect of Process Parameters on Friction Stir Lap Welded 304 Stainless Steel and 5052 Aluminium Alloys
Authors: Chitturi Veerendra , Pedapati Srinivasa Rao , Awang Mokhtar 
Published: February 2021

Abstract
Joining of two different materials like aluminium and steel is a challenging task because of the vast differences in their physical, mechanical and chemical properties. Friction stir welding is a solid-state joining technique which is successful in joining dissimilar materials. In this study, the tool made with Tungsten-Rhenium with a pin length of 4.1 mm is used to weld 4 mm stainless steel and 2 mm aluminium plates in lap configuration with steel as the top plate. The process parameters used in the study are tool rotational speeds between 800 rpm and 1200 rpm, traverse speed ranging from 20 mm/min to 40 mm/min, penetration depth of 4.1 mm to 4.3 mm with a varying tilt between from 0° and 2.5°. The Aluminium is melted during the process because of the high temperature and is thrown out in the form of flash resulting in the formation of defects and a cup like structure at the weld zone. Microstructural analysis confirmed that formation of a sound joint without defects was impossible. The mechanically stirred zone consists of a thin intermetallic layer at the interface of aluminium and steel plates. The thickness of the intermetallic layers formed were between 5 μm and 20 μm. The maximum shear strength of 2.7 kN was achieved with tool rotational speed of 1000 rpm, penetration depth of 4.3 mm and welding speed of 30 mm/min when the angle was tilted at 0°. It is evident from the experiments that the joints achieved were not defect free because of improper mixing of the material.
A Kinematic-Based Unmarked Augmented Reality Method for Large Scene Industrial Workshops
Authors: Ma Zhen , Xu He 
Published: February 2021

Abstract
In the present study, a mobile camera positioning method based on kinematics of robot is proposed, capable of achieving far point positioning of imaging position and attitude tracking in large-scene enhancement. Orbit precision motion via the framework overhead cameras and combined with the ground system of sensor array object (e.g., mobile robot platform of various sensors) is capable of achieving the effective 3D image registration, solving any artifact that refers to a mobile robot in large-space position initialization, as well as effectively implementing the large-space no marks augmented reality, human-computer interaction and information summary. Lastly, the feasibility of the method is verified experimentally.