bluuebunny/crossref_metadata_2025_split huggingface dataset:
A fault diagnosis method based on low signal to noise ratio vibration measurement for use in casing cutters
Authors: Zhang Pu , Liu Shuyao , Tao Aihua , Cheng Jingjing , Gao Peng 
Published: November 2021

Abstract
In this paper, a method for fault diagnosis in casing cutters is proposed. A vibration signal acquisition circuit for use in a high-temperature environment was designed, and a casing cutter measurement model was established, including a model of the casing cutter in a trouble-free state and two other common fault states. The vibration characteristics of the model were analyzed. A fault feature enhancement model based on enhancement of the signal to noise ratio and sparse representation, which effectively solves the fault diagnosis problem caused by the limited installation location and the limited performance of the vibration measurement at high temperature, was also designed. The MobileNet-V3-Small convolutional neural network (CNN) model was improved by reducing the basic blocks of the continuous homogeneous structure in the original model, and the Squeeze and Excitation structure expanded to the global level to obtain a lightweight CNN fault recognition model. The effectiveness and efficiency of the proposed method were validated by various experiments.
Nanopatterning of oxide 2-dimensional electron systems using low-temperature ion milling
Authors: D’Antuono M , Kalaboukhov A , Caruso R , Wissberg S , Weitz Sobelman S , Kalisky B , Ausanio G , Salluzzo M , Stornaiuolo D 
Published: November 2021

Abstract
We present a ‘top-down’ patterning technique based on ion milling performed at low-temperature, for the realization of oxide two-dimensional electron system devices with dimensions down to 160 nm. Using electrical transport and scanning Superconducting QUantum Interference Device measurements we demonstrate that the low-temperature ion milling process does not damage the 2DES properties nor creates oxygen vacancies-related conducting paths in the STO substrate. As opposed to other procedures used to realize oxide 2DES devices, the one we propose gives lateral access to the 2DES along the in-plane directions, finally opening the way to coupling with other materials, including superconductors.
Electrical impedance sensing of organic pollutants with ultrathin graphitic membranes
Authors: Baah Marian , Rahman Afifa , Sibilia Sarah , Trezza Gianmarco , Ferrigno Luigi , Micheli Laura , Maffucci Antonio , Soboleva Ekaterina , Svirko Yuri , Kuzhir Polina 
Published: November 2021

Abstract
In this paper we propose an original approach for the real-time detection of industrial organic pollutants in water. It is based on the monitoring of the time evolution of the electrical impedance of low-cost graphitic nanomembranes. The developed approach exploits the high sensitivity of the impedance of 2D graphene-related materials to the adsorbents. We examined sensitivity of the nanomembranes based on pyrolyzed photoresist, pyrolytic carbon (PyC), and multilayer graphene films. In order to realize a prototype of a sensor capable of monitoring the pollutants in water, the membranes were integrated into an ad hoc printed circuit board. We demonstrated the correlation between the sensitivity of the electric impedance to adsorbents and the structure of the nanomembranes, and revealed that the amorphous PyC, being most homogeneous and adhesive to the SiO2 substrate, is the most promising in terms of integration into industrial pollutants sensors.
Insights of an AI agent via analysis of prediction errors: a case study of fluence map prediction for radiation therapy planning
Authors: Li Xinyi , Wu Q Jackie , Wu Qiuwen , Wang Chunhao , Sheng Yang , Wang Wentao , Stephens Hunter , Yin Fang-Fang , Ge Yaorong 
Published: November 2021

Abstract

Purpose. We have previously reported an artificial intelligence (AI) agent that automatically generates intensity-modulated radiation therapy (IMRT) plans via fluence map prediction, by-passing inverse planning. This AI agent achieved clinically comparable quality for prostate cases, but its performance on head-and-neck patients leaves room for improvement. This study aims to collect insights of the deep-learning-based (DL-based) fluence map prediction model by systematically analyzing its prediction errors. Methods. From the modeling perspective, the DL model’s output is the fluence maps of IMRT plans. However, from the clinical planning perspective, the plan quality evaluation should be based on the clinical dosimetric criteria such as dose-volume histograms. To account for the complex and non-intuitive relationships between fluence map prediction errors and the corresponding dose distribution changes, we propose a novel error analysis approach that systematically examines plan dosimetric changes that are induced by varying amounts of fluence prediction errors. We investigated four decomposition modes of model prediction errors. The two spatial domain decompositions are based on fluence intensity and fluence gradient. The two frequency domain decompositions are based on Fourier-space banded frequency rings and Fourier-space truncated low-frequency disks. The decomposed error was analyzed for its impact on the resulting plans’ dosimetric metrics. The analysis was conducted on 15 test cases spared from the 200 training and 16 validation cases used to train the model. Results. Most planning target volume metrics were significantly correlated with most error decompositions. The Fourier space disk radii had the largest Spearman’s coefficients. The low-frequency region within a disk of ∼20% Fourier space contained most of errors that impact overall plan quality. Conclusions. This study demonstrates the feasibility of using fluence map prediction error analysis to understand the AI agent’s performance. Such insights will help fine-tune the DL models in architecture design and loss function selection.
On the magnetoelectric performance of multiferroic particulate composite materials
Authors: Newacheck Scott , Singh Anil , Youssef George 
Published: November 2021

Abstract
In the current work, quantitative analysis of magnetoelectric particulate composite material system explicated the main mechanisms responsible for the below-optimal performance of this class of materials. We considered compliant particulate composite materials, with constituents relevant to technological and scientific interest, leading to 0–3 Terfenol-D/PVDF–TrFE composite samples. To this objective, thick Terfenol-D/PVDF–TrFE films (10–15 µm) were fabricated and analyzed for chemical, mechanical, and magnetic properties to demonstrate their suitability for energy applications in harsh environmental conditions. The vigorous experimental characterization of the composite exemplified the multifunctional properties, quantifying the interrelationship between the composition and performance. We observed that the addition of magnetic particles to the electroactive copolymer matrix resulted in improvement in the mechanical and electrical properties since the particles acted as pinning sites, hindering the deformation of the chains and enhancing polarization. The effective modulus model was amended to account for the crystallization-induced change in material stiffness. We also measured and computed the magnetic particles motion to explicate the detrimental effect of mobility and migration on the overall magnetoelectric coupling performance of the composite. Thereby, we derived an analytical model based on the magnetic force due to the co-presence of alternating and constant magnetic fields, and the viscous drag force due to the viscoelastic properties of the electroactive copolymer matrix. We demonstrated that the mobility of the particles plays a crucial role in the short and long term performance of magnetoelectric coupling in multiferroic particulate composites, uncovering the underpinnings of the dichotomy in performance between experimentally measured and analytically predicted coupling coefficients, thus allowing for the proposal of new approaches to realize the scientific potential of magnetoelectric particulate composites in energy applications.
Realizing pure shear mode of dielectric elastomers by tuning biaxial prestress of a deformation controller
Authors: Tang Liling , Ding Yuxi , Liu Lei , Zhang Junshi 
Published: November 2021

Abstract
In this article, we propose a method to realize the pure shear deformation mode of dielectric elastomer (DE) membranes by tuning two in-plane prestresses. With utilization of carbon grease electrodes, VHB 4905 membranes are prestretched and attached into a retractable device, forming a pure-shear deformation controller. Experimental results demonstrate that, accurate pure shear deformation mode of DEs can be realized by tuning the mechanical loads in the two directions of the deformation controller. Furthermore, large deformation in the direction of free state can be achieved without electromechanical instabilities. The designed deformation controller accurately realizes the specific pure shear deformation mode of DEs and can be utilized to help design the practical soft actuators.
100 s negative ion accelerations for the JT-60SA negative-ion-based neutral beam injector
Authors: Kashiwagi M. , Hiratsuka J. , Ichikawa M. , Saquilayan G. Q. , Kojima A. , Tobari H. , Umeda N. , Watanabe K. , Yoshida M. , Grisham L. 
Published: November 2021

Abstract
In the negative-ion-based neutral beam injector (N-NBI) of JT-60SA, a hydrogen negative ion beam with energy of 500 keV and a current density of 154 A m−2 for 118 s has been successfully demonstrated. This achievement exceeds the requirements (500 keV, 130 A m−2, 100 s) for the first time. To maintain stable negative ion production for a long pulse, the optimal temperatures of the chamber wall and plasma grid were analytically examined and were experimentally demonstrated. It was confirmed that the temperature during the beam pulse should be <50 °C for the chamber wall and >200 °C for the plasma grid. Damage to the filament cathode due to an abnormal discharge, so-called arcing, has been mitigated by developing a fast cut-off system of the arc current for around 100 μs after the arcing. To maintain sufficient voltage holding capability and to reduce the grid heat load due to the beam in the accelerator, techniques developed for the beam acceleration have been applied to this test. As a result of the integration of these techniques, a stable beam over 100 s has been demonstrated successfully. This is the first achievement over a 100 s stable beam with intensity of >75 MW m−2, which is the required practical level in the N-NBI. These results contribute to the coming NBI system for ITER and DEMO.
Applying the Heaviside step function to simulate the changes of temperature in automotive batteries
Authors: Zakharov N S , Sapozhenkov N O , Tyan R V , Nazarov V P 
Published: November 2021

Abstract
Discharged batteries do not provide the specified voltage in the car’s power supply system during parking, which can cause malfunctions of electrical equipment and an increase in the quiescent current in the on-board network, due to incorrect operation of electronic control units responsible for the operation of self-diagnosis systems, anti-theft alarm, multi-media, maintaining a thermal state, etc. Therefore, to ensure a reliable start of the ICE and the proper operation of the electrical equipment of a car at low temperatures, it is required to maintain the battery in a charged state. Vehicle generator is selected taking into account the nominal capacity of the battery, power and operating modes of electrical consumers, which excludes the battery operation with a low level of charge. However, when operating cars in large cities in winter, the battery charge level decreases. Deterioration of the battery charging characteristics, increased power consumption of additional equipment and low speed of movement of cars in the city with frequent stops at intersections are the reasons for the decrease in the efficiency of the battery charge. In such conditions, the battery can be discharged not only by starting the ICE and turning on consumers in the parking lot, but also when the ICE is idling and at low crankshaft speeds while driving on city routes and during rush hours. Considering that the operational characteristics of the battery change significantly with decreasing temperature, studies aimed at establishing and predicting the battery temperature during operation are relevant.
Investigation of the operation of a ship’s synchronous generator based on a numerical model
Authors: Grinek AV , Boychuk IP , Fishenko A M , Savosteenko NV , Gerasimenko O N 
Published: November 2021

Abstract
The article presents the results of modeling a ship’s synchronous generator. Based on preliminary design calculations, a geometric model of the generator was built. The static and overclocking processes of the generator are investigated. For static modes, the frequency response of the process is obtained. A numerical model was used to identify a mechanical defect. On the example of a simulated defect of an electrical machine - the eccentricity of the generator rotor, the signature of the defect signal is obtained. The study revealed that the presence of rotor eccentricity leads to the appearance of a harmonic component in the spectrum of the force of large amplitude with a maximum value at a low frequency. Transient analysis was carried out using wavelet transformations. The results of the study of dynamics show how the rotor speed increases. The simulation revealed three frequency regions of the signal under study: the region of the increase in speed, the achievement of the critical speed (between the second and third seconds), and the exit to the steady-state. A diagram of a system for diagnosing defects in an electrical machine using a digital twin - a numerical model is proposed. Generator defects (mechanical and electromechanical) can be identified based on model data. Databases of defect signatures in a static mode and a diagnostic model, which contains algorithms for deciding on the presence of a defect, can serve as the basis of information for an operator to decide.
Development, features and prospects of application of AMP / cold ironing marine power systems
Authors: Ignatenko A V , Migel D V , Deruzhinsky G V , Kravchenko N A 
Published: November 2021

Abstract
The evolution and current state of the technology for supplying ships from the shore under high voltage - alternative power from the shore (APS), known as “Alternative Maritime Power® (AMP®), cold ironing (CI) and high voltage shore connection (HVSC) are described. The structure of the system and existing methods of implementation, mandatory components, depending on the system version are considered. The need for national adaptations of the international versons, the unification of existing technical solutions and their development trends, taking into account high-voltage technologies is emphasized. Advantages and challenges of environmental impacts, expected phased tightening of environmental regulations, including the maritime legislation (the MARPOL convention), as well as promising initiatives in the context of global decarbonization trends are described. The need to take into account purposes and cargo capacity and regions of operation of ships, to develop the port infrastructure, and make clean electricity available is emphasized.
Monitoring and charging level alignment system for a vehicle hybrid power unit battery pack
Authors: Bakhmutov S V , Kuznetsov A V , Sizov Y A , Chernokozov V V 
Published: November 2021

Abstract
The article is devoted to the actual problem of developing effective means of control and charging level alignment of the vehicle hybrid power unit (HPU) accumulators. A description of the automatic control and charging level alignment system of the battery pack for hybrid power unit developed by the authors, while simultaneously controlling the temperature of each battery, the originality of which is protected by patents of the Russian Federation, is provided.The device is distinguished by the simplicity of the circuit design, its own low energy consumption and potentially low cost. To check the efficiency of the proposed device the computer simulation and experimental study were carried out. As a result of the provided multifactorial experiment, a regression function was obtained, which allows, by the value of the obtained coefficients, to reveal the degree of inhomogeneity of the monitored batteries in terms of electrical parameters and the temperature of influence, as well as to take into account the effects of pair and quadratic interactions.
Dependence of the increase in the power reserve of an electric vehicle on the season when using a non-flat battery of photovoltaic converters
Authors: Kozlov V N , Kolbasov A F , Karpukhin K E , Katanaev N T 
Published: November 2021

Abstract
Due to the fight against CO2 emissions and other harmful substances, the world’s leading vendors of motor vehicles (MV) come back to development of electric vehicles (EV) as the most environmentally friendly transport. But EV has inadequate power reserve from one accumulators charge. One of the ways to increase it is to use additional environmentally friendly electrical energy sources, e.g., photovoltaic converter (PVC) batteries due to the increase in their efficiency. In order to improve aerodynamic, design and consumer properties, the world’s leading EV manufacturers pass from flat PVC battery to non-flat. Non-flat PVC batteries compared with flat have insufficient energy efficiency, which can be increased in several ways, including PVC battery segmentation. In scientific publications, there are no methods for calculating non-flat PVC batteries, which indicates the actuality of the research being conducted. Mathematical modeling of the EV power reserve depending on the season allows us to justify the actuality of segmenting the non-flat PVC batteries installed on the EV. Materials for the mathematical modeling of nonlinear interaction are obtained experimentally, the method of conducting experimental research is scientifically justified. As a result of the mathematical modeling, the dependences of EV power reserve on the season at different standard test cycles were obtained. The obtained dependences of the EV power reserve on the season allow us to assume the feasibility of segmenting the PVC batteries installed on the EV to increase the energy output and EV power reserve from one accumulators charge.
Development and validation of vehicle wheel load scaling method for formation of durability testing loading cycle
Authors: Bokarev A I , Kulagin V A , Nazarkov I A 
Published: November 2021

AbstractFor a vehicle durability study, performed with simulation or laboratory testing, impact on the object should be described as set of time-domain load signals, which reflects accelerated service modes of a vehicle operation. For a newly developed vehicle these load signals can be based on previously prepared loading cycle of a similar vehicle with use of the load scaling theory. Importance and certainty of the load scaling theory is approved by active use among foreign car makers and engineering centers. However, mathematical description of the theory and scaling procedure are strictly classified, despite of being based on fundamentals of vehicle dynamics. In this paper the method of scaling of time-domain wheel and driveline loads is suggested; the method is based on proportions of size and mass properties of the original and the new vehicles. Assumed that previously recorded loading cycle corresponds to the service life of a vehicle. It is worth noting that level of loading and damage accumulation, shown with scaled loading cycle and after first prototypes testing on a proving ground, will be different because of impact of chassis stiffness and damping properties. Suggested scaling theory is being studied in FSUE “NAMI” and is on the validation and verification stage. First completed experiments showed that a multiaxial test rig could perform the vehicle suspension loading cycle, obtained with the theory, with a satisfactory accuracy. This makes utilization of the theory limited to early stages of vehicle development.
Method of formation of loading cycles for performing forced bench tests of suspension elements at the stage of technical design
Authors: Nazarkov I , Bokarev A , Plotnikov A , Bakhmutov S V 
Published: November 2021

AbstractEnsuring the required vehicle service life is one of the most important and topical global engineering challenges. Automobile manufacturers and research engineers around the world are actively working to improve safety and durability testing methods of vehicles, their components and systems. This article touches upon the main issues of comparing the modes of vehicle road operation and the method of forming an adequate program for extreme testing of suspension elements. The developed method has been actively applied in FSUE “NAMI” in the field of research on durability of vehicle components and systems, in particular, of hub units, with the use of mathematical modeling tools and the test base capacities and capabilities.
Optimization of mechatronic drives motion laws for automated equipment
Authors: Matsko O N 
Published: November 2021

Abstract
At present, when designing mechatronic cyclic drives the developer as a rule chooses the law of motion, specifying as input data, the cycle time and the amount of movement and often introducing restrictions, for example, on maximum acceleration in case of developing high-speed drives. However, this approach leads to an overestimation of the maximum drive power and, as a result, a significant increase in energy consumption. In this paper it is shown that by choosing a rational law of motion of the drive at the stage of equipment design, it is possible to achieve a sufficiently effective optimization according to various criteria. The efficiency of optimization of different motion laws of cycle drives according to various criteria is analyzed. The dependences between the maximum instantaneous power, the amount of movement, the speed and energy consumption are established and graphically presented confirming the effectiveness of the rational choice of the law of motion parameters under an inertial load. At the same time, it is shown that when synthesizing the law of motion, it is necessary to take into account the maximum possible number of parameters so that the improvement of some parameters does not lead to a decrease in other parameters.
Control of a reversible electric machine included in the vehicle suspension
Authors: Zamyslov V 
Published: November 2021

Abstract
The relevance of the work is due to the constantly growing requirements for the ride comfort of automobiles. The purpose of the study is a rational choice and combination of principles for constructing an algorithm for controlling an electric machine, replacing a hydraulic damper in the design of a vehicle’s suspension system. The study of the behavior of suspension, depending on the applied control algorithms, was carried out by the method of mathematical modeling. In this work, the control of the suspension of one wheel was considered. The angular and longitudinal oscillations of the body were not the subject of this study. In this regard, the applied design scheme is two-mass. The positive and negative aspects of various principles for calculating the target force generated by an electric machine are considered, and an algorithm for calculating the magnetic flux and armature current of an electric machine necessary for the implementation of the target force under various conditions is developed. It is shown that the calculation of the target force should be based on a combination of several principles, since this allows significant expanding of the suspension operating conditions range.