bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative study of shaking based on non-destructive testing of steel wire ropes
Authors: Guo Zichang , Luo Han , Zhuo Jianguo , Zhang Chengzhuo , Li Xinyue 
Published: May 2022

AbstractDue to the superiority of wire rope in strength, cost, ductility and other characteristics, wire rope has become an irreplaceable material in metallurgy, mining, oil and gas drilling, machinery, chemical industry, aerospace and other fields. Therefore, the wire rope flaw detection is very important work, and in the wire rope detection, jitter is very serious interference. In this article, we firstly discuss the quantitative relationship between displacement and direction of shaking and leakage magnetic field, and this study can also be used as a essential basis for subsequent quantitative studies of local flaws to remove the effect of shaking on leakage magnetic signal.
A temperature field reconstruction method for debonding defect identification in laminated structures
Authors: Wu T.T. , Zhang C. , Ji H.L. , Tao C.C. , Qiu J.H. 
Published: May 2022

Abstract
The surface temperature is an important parameter capable of detecting and quantifying defects in laminated structures if subjected to a thermal load. In this paper, a temperature field reconstruction method is developed to detect the size of debonding defect in laminated structures. A Tikhonov regularization based conjugate gradient method (CGM) is applied to reconstruct the temperature field of a laminated structure for determination of the size of a debonding defect. Tikhonov regularization deals with the severe ill-posedness and the CGM is used for solving the minimization problem. Some simulation examples are carried out to validate the effectiveness and stability of the inverse analysis. Results show that for small defects, the defect detection results based on temperature field reconstruction have higher accuracy than that detected directly by available surface temperature measurement.
Instantaneous lift-off distance estimation in magnetic flux leakage testing of steel wire ropes
Authors: Zhou Jianguo , Ren Liyuan , Liu Zhiliang 
Published: May 2022

Abstract
Steel wire rope (SWR) defects plagued its application in many important fields, such as cranes, ports, etc. However, the accuracy of SWRs’ local flaws detection based on magnetic flux leakage (MFL) method is susceptible to the lift-off distance. This paper proposes an instantaneous lift-off distance estimation method to study the effect of lift-off distance on MFL detection for SWR. We firstly derive the relation between the lift-off distance and the MFL field strength based on the magnetic dipole model. After obtaining the time-frequency representation of the MFL signal by using multi-synchrosqueezing transform, we extract the instantaneous amplitude (IA) of the strand signal without other noise interference. Finally, the nonlinear least-squares method is used to fit the relation between the IAs of the strand signals and the lift-off distances to achieve the estimation of the instantaneous lift-off distance. A SWR with three local flaws is tested to validate the proposed method. This work provides instantaneous monitoring of lift-off distances, and it can be used in future noise suppressing methods development or quantitative analysis of local flaws.
Modal analysis of full-scale wind turbine blade structural fatigue tests based on particle swarm optimization
Authors: Han M Q , Ma Q , Zhang Y , An Z W 
Published: May 2022

Abstract
Modal analysis is the vital prerequisite of the full-scale fatigue test of the wind turbine blade. In order to resolve the difficulty in solving the characteristic equation of the transfer matrix method in modal analysis, a method of solving the characteristic equation based on particle swarm optimization is proposed. Firstly, the beam model is used to simplify and discrete the blade along the spanwise of the blade. A concept of average bending stiffness is used for the elasticity assignment with beam segment, and the blade kinematics model is established. Subsequently, a designed particle swarm optimization is used to solve the characteristic equation. Finally, the proposed method is verified by modal analysis of an MW-scale blade. On this basis, the effect of the mass and position of the counterweight on the mode shape is investigated. The results indicate that the proposed method can provide a theoretical reference for the fatigue test technology of wind turbine blades.
Validation of Fatigue Model of a Hydraulic Shock Absorber Equipped with Shim Stack Valves
Authors: Czop Piotr , Slawik Damian 
Published: May 2022

Abstract
The aim of the paper is to formulate and validate the fatigue model of a shock absorber equipped with shim-based clamped valves. The fatigue model has application potential in a virtual valve system pre-selection process during the shock absorber design and configuration stage. It allows the required testing capacity at shock absorber manufacturers to be significantly reduced, i.e. the number of long-term and expensive fatigue tests performed on servo-hydraulic load frame testers. The shock absorber fatigue model is a combination of the previously developed finite element model [1] and analytical routines using the experimentally derived Wöhler characteristics of shim materials [2]. The fatigue model validation process was conducted with a high-performance servo-hydraulic load frame tester. Six shock absorbers were subjected to the same long-cycle kinematic sine-load and tested until initial valve damage symptoms appeared. The paper reports the fatigue calculation process and validation results. The obtained model accuracy in the range of ±30% error of shock absorber life-time prediction. This result is accurate enough for the model to be recommended as a quick-and-dirty engineering tool saving shock absorber development costs.
Dynamic evaluation of a shock absorberwith the use of additional noncontact in-fluid laser measurementsof the intake base valve
Authors: Czop Piotr 
Published: May 2022

Abstract
The aim of this paper is to evaluate vibrations of a semi-active shock absorber take-apart unit assembled with a base valves replaced during conducted evaluation test with the same valve component. Intake valves significantly contribute to the overall vibration level of the shock absorber. The valves are further recalled in the paper as "OK" and "NOK" corresponding to audible noise perception criteria. These criteria are frequently subjective and difficult to be expressed by a technical specification. The take-a-part unit was evaluated by means of piston- rod acceleration in the time-frequency domain. The analysis was completed by other measurements (i.e. load, compression and rebound pressures, and intake valve opening displacement) in order to correlate their waveforms with spectrogram maps. The intake valve opening value (i.e. displacement of the shim supported by the coil spring) was measured using three laser sensors which were capable to conduct measurements directly in fluid. The wavelet time-frequency analysis based on the synchrosqueezing transform (SST) was applied in order to identify the fingerprint OK and NOK valve. A servo-hydraulic tester was used in order to apply a sine-wave excitation to the shock absorber. The experiments involved the soft and hard settings of the semi-active shock absorber corresponding to low (I=0.29 A) and high (I=1.6A) value of the current applied to the internal servo-valve.
Design theory and method of damping rings attached to aviation gears with high speed
Authors: Xu Ziyang , Wei Jing , Wei Haibo , Liu Zhirou , Chen Xiangqian 
Published: May 2022

Abstract
Gears, having thin rim and disk, are widely used in aviation transmission systems, while the traveling wave resonance is easily induced due to the high speed and wide working range. Although attaching damping rings to these gears is an effective solution, the current research lacks the in-depth comparison and specific design methods of various damping rings. Thus, this paper systematically analyses the design theory and method of attaching damping rings to the aviation gear. A system is established to determine the design operating points of the additional damping ring. Various damping ring design schemes are compared from multiple aspects and the friction energy dissipation mechanism is analysed. The design method for the damping ring structure parameters is put forward.
Digitalization Workflow for Automated Structuring and Standardization of Maintenance Information of Wind Turbines into Domain Standard as a Basis for Reliability KPI Calculation
Authors: Lutz Marc-Alexander , Walgern Julia , Beckh Katharina , Schneider Juliane , Faulstich Stefan , Pfaffel Sebastian 
Published: May 2022

Abstract
Maintenance data of wind turbines is an important information source for calculating key performance indicators. Also, it can be used for developing models for early fault detection. Both activities aim for supporting informed decisions in operation and maintenance. However, such data is rarely available in a structured and standardized format which hinders the interoperability of different enterprises. Consequently, maintenance information is often unused or only usable with considerable personnel effort. To digitalize wind farm maintenance, a digitalization workflow is developed and presented in this paper. The workflow consists of the steps optical character recognition, information extraction and text classification. The workflow is applied on real-world wind turbine service reports and invoices. First results for each step show good performance metrics and potential for further real-world application of the proposed method.
Investigation and standardisation of electrolysers for green hydrogen production using the test infrastructure in Bremerhaven, Germany
Authors: Beck Lorenz , Barthel Jannik , Quistorf Gesa , Schalk Kevin , Denecke Nora 
Published: May 2022

Abstract
To realise the installation targets of 10 GW electrolysis capacity in Germany and 40 GW in the EU until 2030, extensive standardisation and testing is required. The electrical characteristics of electrolysers need to be fully understood and mastered for a reliable operation within distribution grids and decoupled grids of systems to produce green hydrogen, e.g. off-shore. Using a modular test infrastructure and multi-functional test pads, electrolysers, but also fuel cells and CHP units, can be tested in emulated grid conditions. To emphasize the range of feasibility regarding testing, three different scenarios were developed, covering the challenges between single unit grid connection and offshore hydrogen production. The test results serve as input for standardisation committees to expand existing and develop new guidelines.
FLOTANT concept: floater design, integrated modelling & global performance
Authors: Serret Jordi , Kahn Bernardo , Cavanagh Bruce , Lorente Patricia , Pascal Remy , Girandier Clementine , McEvoy Paul , Cortés Carlos , Duran Rubén , Romero Alejandro 
Published: May 2022

Abstract
This paper presents the final design of the FLOTANT concept developed within the framework of a Cooperation Research Project funded by the European Union’s Horizon 2020 research and innovation programme. The FLOTANT concept is a hybrid concrete-plastic barge-type floating offshore substructure holding a 12MW wind turbine; buoyancy is achieved using plastic material (foam) fitted within the floater substructure. The paper describes the FLOTANT project innovations and presents the principal dimensions of the floating wind turbine system. The floating system has been developed to fulfil strict requirements at two different locations: Gran Canarias (GC) and West of Barra (WoB) sites. Therefore, two different mooring solutions including innovative elastomers to reduce peak loads are presented. The floating system’s intact and damaged static stability is checked along with the hydrostatic and hydrodynamic properties, showing the low-cost barge-type system’s feasibility.
To ensure the desired behaviour of the floating system, a relevant subset of design load cases (DLCs) based on international standard requirements have been simulated checking the global performance of floater and moorings. Fully coupled hydro-servo-aero-elastic simulations have been performed to consider the wind and wave loading, the aerodynamic response of the rotor, the hydrodynamic response and structural dynamics of the turbine-floater-mooring assembly, and the control system actions. A summary of the results of the last design loop within the FLOTANT project is presented.
Predictive Maintenance of Floating Offshore Wind Turbine Mooring Lines using Deep Neural Networks
Authors: Gorostidi N , Nava V , Aristondo A , Pardo D 
Published: May 2022

Abstract
The recent massive deployment of onshore wind farms has caused controversy to arise mainly around the issues of land occupation, noise and visual pollution and impact on wildlife. Fixed offshore turbines, albeit beneficial in those aspects, become economically unfeasible when installed far away from coastlines. The possibility of installing floating offshore wind turbines is currently hindered by their excessive operation and maintenance costs. We have developed a comprehensive model to help companies plan their operations in advance by detecting failure in mooring lines in almost real time using supervised deep learning techniques. Given the lack of real data, we have coupled numerical methods and OpenFAST simulations to build a dataset containing the displacements and rotations of a turbine’s floating platform across all directions. These time series and their corresponding frequency spectra are used to obtain a set of key statistical parameters, including means and standard deviations, peak frequencies, and several relevant momenta. We have designed and trained a Deep Neural Network to understand and distinguish amongst a series of common failure modes for mooring lines considering a range of metocean and structural conditions. We have obtained promising results when monitoring severe changes in the line’s mass and damping using short time spans, achieving a 95.7% validation accuracy when detecting severe biofouling failure.
Time domain hydrodynamics at panel level: an application to the structural analysis of Telwind
Authors: Rodriguez-Lôpez E , Moreno-Narrillos C , Rueda-Guglieri F , Yáñez-González Á 
Published: May 2022

Abstract
The current modelling approaches for Floating Offshore Wind Turbines (FOWT) present some limitations in the representation of the fluid-solid interaction. Mainly, they do not consider full flexibility of the floating body, so internal forces on the platform cannot be resolved. ESTEYCO has developed a novel methodology to couple all the actions (hydrodynamics, structural, aerodynamics, control, etc.) that are applied over a FOWT concept. The main novelty of this approach resides in selecting Abaqus (well stablished Finite Element –FE– tool) as the central solver of the motion equations, naturally enabling inclusion of full platform flexibility (and not only rigid bodies linked by flexible members). The inclusion of the coupled hydrodynamic actions (highly dependent on platform movement) is performed through a novel tool: EST-PANEL which provides the time domain hydrodynamic pressure at panel level. This approach is thoroughly validated against other well established modelling techniques showing outstanding agreement both in platform movement and internal tension of cables. This methodology has been developed to support the design and development of ESTEYCO’s own technology: Telwind. The current approach thus provides a unique fully coupled FE tool to perform a detailed structural assessment of the floating platform even from the earliest conceptual stages of the design. In addition, the current approach can be easily extended to simulation of some loading scenarios (cable breaking, transient deployment, non-linearities) that are not easy to model with other simulation tools.
Influence of blade deflections on wind turbine noise directivity
Authors: Bresciani A P C , Boatto U , Le Bras S , Bonnet P , de Santana L D 
Published: May 2022

Abstract
This paper establishes the effect of blade deflections on wind turbine noise directivity. Fast turn-around methods are used in a framework of integrated aeroelastic and aeroacoustic simulations: the blade element momentum theory is coupled with a RANS-informed Amiet’s model for the aeroacoustic modelling of trailing- and leading-edge noise. This approach is applied to the NREL 5 MW wind turbine and the results of rigid and flexible blades are compared. The overall sound pressure level computed with flexible blades increases up to 13 dBA for listeners close to the rotor plane. This effect is attributed to the flapwise angular deflection of the wind turbine blade. Furthermore, the symmetry of the results with respect to the rotor plane is lost when the flapwise deflection is considered, indicating that the modelling of this rotation is of fundamental importance for the acoustic simulation.
Investigation of a converter fault for a DFIG wind turbine and analysis of the resulting gearbox component loads
Authors: Röder Julian , Jacobs Georg , Bosse Dennis , Herzog Fabian , Graf Lukas 
Published: May 2022

Abstract
Doubly fed induction generators are widely used in wind turbines in the field. The main advantage is the significantly lower cost of the partial scale power converter compared to the full scale power converter. Converter faults in wind turbines lead to significant generator torque excitations that lead to dynamic loads in the drivetrain. Dynamic loads and changing rotational speeds can lead to gearbox damages. The generator torque excitations have the highest influence on the high speed shaft torque due to the coupling to the generator. Gearbox damages occur mainly on the components of the high speed shaft. Thus, in this paper the influence of a converter fault in a wind turbine with doubly fed induction generator on the high speed shaft component damages is investigated. It is shown that the converter fault can induce dynamic torque excitations with a maximum increase to around 2.5 times rated torque. Due to the resulting dynamic gearbox loading the safety against scuffing in the high speed gear stage decreases by maximum 19 percent. The smearing risk in the high speed shaft bearings increases to around 2 times the value during rated power production.
Machine learning based met data anomaly labelling
Authors: Talayero Ana P. , Yürüşen Nurseda Y. , Ramos Francisco José Sánchez , Gastón Roberto Lázaro 
Published: May 2022

Abstract
Data preprocessing is the initial and utmost critical phase of wind resource assessment and wind power curve performance analysis. Without ensuring high quality and site representative data availability, an evaluation for the wind resource potential of a wind farm site means investment decision making involving a great deal of uncertainty. The current practice in the field is to use fix rules and via data scanning by manual labouring of data field experts. Although rule-based (if-else, interval-based) prefiltering applications can be found in some commercial software, and these rules are also limited for addressing the needed preprocessing requirements fully. Therefore, this process is time consuming and causes inefficient resource allocation considering the manual scanning process performed by data scientists & experts. In this study, reviewed data by experts are used as data with correct labels, and then efficient classifiers are generated by applying machine learning algorithms to unfiltered and filtered data. It is reported that tree-based classifiers are performing better.
Identification of electromagnetic and hadronic EASs using neural network for TAIGA scintillation detector array
Authors: Astapov I. , Bezyazeekov P. , Blank M. , Bonvech E. , Borodin A. , Brueckner M. , Budnev N. , Bulan A. , Chernov D. , Chiavassa A. , Dyachok A. , Gafarov A. , Garmash A. , Grebenyuk V. , Gress E. , Gress O. , Gress T. , Grinyuk A. , Grishin O. , Horns D. , Igoshin A. , Ilyushin M. , Ivanova A.D. , Ivanova A.L. , Kalmykov N. , Kindin V. , Kiryuhin S. , Kokoulin R. , Kompaniets K. , Korosteleva E. , Kozhin V. , Kravchenko E. , Kryukov A. , Kuotb A. , Kuzmichev L. , Lagutin A. , Lavrova M. , Lemeshev Y. , Lubsandorzhiev B. , Lubsandorzhiev N. , Lukanov A. , Lukyantsev D. , Malakhov S. , Mirgazov R. , Mirzoyan R. , Monkhoev R. , Osipova E. , Pakhorukov A. , Pan A. , Pankov L. , Panov L. , Petrukhin A. , Poddubnyi I. , Podgrudkov D. , Poleschuk V. , Ponomareva V. , Popesku M. , Popova E. , Porelli A. , Postnikov E. , Prosin V. , Ptuskin V. , Pushnin A. , Raikin R. , Rubtsov G. , Ryabov E. , Sagan Y. , Samoliga V. , Satyshev I. , Silaev A. , Silaev(junior) A. , Sidorenkov A. , Sinegovsky S. , Skurikhin A. , Sokolov A. , Sulakov V. , Sveshnikova L. , Tabolenko V. , Tanaev A. , Tarashchansky B. , Ternovoy M. , Tkachev L. , Tluczykont M. , Togoo R. , Ushakov N. , Vaidyanathan A. , Volchugov P. , Volkov N. , Vorobyov V. , Voronin D. , Wischnewski R. , Zagorodnikov A. , Zhaglova A. , Zhurov D. , Yashin I. 
Published: May 2022

Abstract
The TAIGA experiment in Tunka valley is expanding the present scintillation detector array with new TAIGA-Muon detector stations. A simulation model was developed for optimization of the layout of the new stations and study of the identification performance of the array. The extensive air showers (EASs) were simulated with the CORSIKA simulation tool, and the detector response was simulated with the GEANT4 package. EASs induced by gamma quanta or protons in the energy range from 1 PeV to 10 PeV and the zenith angle range from 0° to 45°, are used for these studies. For the identification of high energy extensive air showers, a method based on a neural network was suggested. With this method, the proton identification efficiency is more than 90%, while the gamma identification efficiency not less than 50%.
A bio-inspired polarization navigation sensor based on artificial compound eyes
Authors: Liu Jianying , Zhang Ran , Li Yahong , Guan Chuanlong , Liu Rui , Fu Jiaxin , Chu Jinkui 
Published: May 2022

Abstract
Insect compound eyes are optical systems with small volume and a compact structure. The ommatidia in the dorsal rim area of some insects have polarized vision, which can perceive the polarization pattern of the sky and provide them with navigation information. In this paper, inspired by the polarization-sensitive compound eyes of insects, a bio-inspired polarization navigation sensor based on artificial compound eyes is designed. The sensor consists of an artificial compound eye, an integrated polarization detector and an integrated circuit. The optical path of the sensor uses the lens defocus method, which can ensure that the sensor obtains redundant polarization information. The integrated polarization detector is used to obtain the polarization information of the incident light, and the integrated circuit is responsible for the calculation. To extract effective information from images, we propose a multi-threshold segmentation method to filter and classify effective pixels. We use the least squares method to fit the inherent error of the sensor and then compensate it. The indoor calibration accuracy of the sensor is ±0.3°, and the outdoor calibration accuracy is ±0.5°. The sensor can provide accurate direction information for general smart mobile devices. The size of the sensor is 4 × 4 × 2 cm, and the weight is only 15 g. The key components of the sensor can be mass-produced, and it is a miniaturized and low-cost polarization navigation sensor.