bluuebunny/crossref_metadata_2025_split huggingface dataset:
Periodic error detection and separation of magnetic levitation gyroscope signals based on continuous wavelet transform and singular spectrum analysis
Authors: Wang Yiwen , Yang Zhiqiang , Shi Zhen , Ma Ji , Liu Di , Shi Ling 
Published: March 2022

Abstract
The accuracy of the north azimuth measured using the magnetic levitation gyroscope (GAT) declines owing to the influence of the periodic errors of GAT signals induced by the systematic error of the gyro rotor system and the influence of external environment. To address this issue, this paper proposes a novel methodological strategy based on continuous wavelet transform (CWT) and singular spectrum analysis (SSA) to process GAT periodic errors and improve the accuracy of north-seeking. Firstly, CWT is used to process a large number of GAT signals to obtain the statistical characteristics of the periodic errors. Subsequently, the reconstructed components (RCs) of the GAT signals are obtained using SSA. After detecting and grouping the periodic terms contained in each RC using CWT, the periodic errors in the GAT signals are clearly separated. Finally, the effectiveness of this method was verified by comparing our north azimuths with those measured using the high-precision global navigation satellite system (GNSS) baseline. Our results indicated that the periodic errors in GAT signals can be accurately divided into the high frequency periodic error and the low frequency periodic error, and both periodic errors can be clearly detected and separated. After processing, the root mean square error of the GAT rotor currents and the absolute difference between the gyro and high-precision GNSS north azimuths were enhanced by 22.6% and 43.2%, respectively. The method presented in this paper to process periodic errors is suitable for use in the preprocessing of GAT signals.
A novel dynamic method for the storage of calibration gas mixtures based on thermal mass flow controllers
Authors: Loianno Valerio , Mensitieri Giuseppe 
Published: March 2022

Abstract
A dynamic method for the storage of calibration gas mixtures is presented using thermal mass flow controllers (MFCs) connected to a dead end volume. The approach relies on barometry to calibrate the unknown constant volume and two MFCs which regulate the flow rate of carbon dioxide and methane respectively. Binary gas mixtures of these components are prepared and stored within the calibrated volume tank up to 9 bar at ambient temperature. Thermodynamic data of pressure, temperature and density of the gas mixtures are retrieved. The expanded uncertainties at 95% confidence level of the molar fraction and the density of the mixture are evaluated. FTIR Spectroscopy is used in situ to analyse the gas mixtures.
The microwave properties of tin sulfide thin films prepared by RF magnetron sputtering techniques
Authors: Dragoman Mircea , Aldrigo Martino , Dinescu Adrian , Iordanescu Sergiu , Romanitan Cosmin , Vulpe Silviu , Dragoman Daniela , Braniste Tudor , Suman Victor , Rusu Emil , Tiginyanu Ion 
Published: March 2022

Abstract
In this paper we present the microwave properties of tin sulfide (SnS) thin films with the thickness of just 10 nm, grown by RF magnetron sputtering techniques on a 4 inch silicon dioxide/high-resistivity silicon wafer. In this respect, interdigitated capacitors in coplanar waveguide technology were fabricated directly on the SnS film to be used as both phase shifters and detectors, depending on the ferroelectric or semiconductor behaviour of the SnS material. The ferroelectricity of the semiconducting thin layer manifests itself in a strong dependence of the electrical permittivity on the applied DC bias voltage, which induces a phase shift of 30 degrees mm−1 at 1 GHz and of 8 degrees mm−1 at 10 GHz, whereas the transmission losses are less than 2 dB in the frequency range 2–20 GHz. We have also investigated the microwave detection properties of SnS, obtaining at 1 GHz a voltage responsivity of about 30 mV mW−1 in the unbiased case and with an input power level of only 16 μW.
Temperature-dependent resistance of carbon nanotube fibers
Authors: Song Yanhui , Di Jiangtao , Jia Yinlei , Yong Zhengzhong , Xu Jifeng 
Published: March 2022

Abstract
Carbon nanotube fibers are highly recommended in the field of temperature sensor application owing to their excellent electrical conductivity and thermal conductivity. Here, this work demonstrated the rapid thermal response behaviour of CNT fibers fabricated by floating catalyst CVD method, which was measured by an in situ technique based on the CNT film electric heater with excellent electrothermal response properties. The temperature dependences of resistance and structure were both explored. Experimental investigation indicates that the reduction in the inter-CNT interspace in the fibers caused by thermally driven actuation was dominantly responsible for the decrease of the fibers resistance during the heating process. Especially, the heated fibers showed 7.2% decrease in electrical resistance at the applied square-wave voltage of 8 V, and good temperature sensitivity (−0.15% °C−1). The as-prepared CNT fibers also featured a rapid and reversible electrical resistance response behaviour when exposed to external heating stimulation. Additionally, with the increment of temperature and twist-degree, the generated contraction actuation increased, which endowed the CNT fibers with more decrease in electrical resistance. These observations further suggested that the temperature-dependent conduction behavior of the CNT fibers with a high reversibility and repeatability was strongly correlated with their structure response to heat stimulation. As a consequence, the temperature-conduction behavior described here may be applied in other CNT-structured fibers and facilitated the improvement in their temperature-sensing applications.
MAPbBr3 nanocrystals from aqueous solution for poly(methyl methacrylate)-MAPbBr3 nanocrystal films with compression-resistant photoluminescence
Authors: Tang Xiaobing , Zhang Yulin , Kothalawala Nadeesha Lakmali , Wen Xiyu , Kim Doo Young , Yang Fuqian 
Published: March 2022

Abstract
In this work, we develop an environmental-friendly approach to produce organic-inorganic hybrid MAPbBr3 (MA = CH3NH3) perovskite nanocrystals (PeNCs) and PMMA-MAPbBr3 NC films with excellent compression-resistant PL characteristics. Deionized water is used as the solvent to synthesize MAPbBr3 powder instead of conventionally-used hazardous organic solvents. The MAPbBr3 PeNCs derived from the MAPbBr3 powder exhibit a high photoluminescence quantum yield (PLQY) of 93.86%. Poly(methyl methacrylate) (PMMA)-MAPbBr3 NC films made from the MAPbBr3 PeNCs retain ∼97% and ∼91% of initial PL intensity after 720 h aging in ambient environment at 50 °C and 70 °C, respectively. The PMMA-MAPbBr3 NC films also exhibit compression-resistant photoluminescent characteristics in contrast to the PMMA-CsPbBr3 NC films under a compressive stress of 1.6 MPa. The PMMA-MAPbBr3 NC film integrated with a red emissive film and a blue light emitting source achieves an LCD backlight of ∼114% color gamut of National Television System Committee (NTSC) 1953 standard.
Impact and workload are dominating on-field data monitoring techniques to track health and well-being of team-sports athletes
Authors: Cheng Runbei , H M Bergmann Jeroen 
Published: March 2022

Abstract

Objective. Participation in sports has become an essential part of healthy living in today’s world. However, injuries can often occur during sports participation. With advancements in sensor technology and data analytics, many sports have turned to technology-aided, data-driven, on-field monitoring techniques to help prevent injuries and plan better player management. Approach. This review searched three databases, Web of Science, IEEE, and PubMed, for peer-reviewed articles on on-field data monitoring techniques that are aimed at improving the health and well-being of team-sports athletes. Main results. It was found that most on-field data monitoring methods can be categorized as either player workload tracking or physical impact monitoring. Many studies covered during this review attempted to establish correlations between captured physical and physiological data, as well as injury risk. In these studies, workloads are frequently tracked to optimize training and prevent overtraining in addition to overuse injuries, while impacts are most often tracked to detect and investigate traumatic injuries. Significance. This review found that current sports monitoring practices often suffer from a lack of standard metrics and definitions. Furthermore, existing data-analysis models are created on data that are limited in both size and diversity. These issues need to be addressed to create ecologically valid approaches in the future.
A variable reluctance based rotational electromagnetic harvester for the high-speed smart bearing
Authors: Gong Yun , Wang Sijia , Xie Zhengqiu , Zhang Tao , Chen Zhiwen , Lin Wanrong , Huang Wenbin 
Published: March 2022

Abstract
In recent years, smart bearing technology is being developed for the purpose of prolonging the reliability and the service time of bearing by detecting the early faults and regulating the working condition. However, powering wireless monitoring devices integrated within the smart bearing is still an uphill task due to the limited power capacity and lifetime of traditional power cells. In this paper, a variable reluctance energy harvester (VREH) is proposed to scavenge the rotating energy from the bearing, which includes a toothed spacer and an m-shape electric steel with a coil and a permanent magnet on each leg. The key parameters of the proposed harvester are analyzed and discussed via the theoretical study and the finite element analysis. In comparison with the VREH without the middle magnet, the proposed harvester greatly improves the energy harvesting performance and reduces the magnetic flux leakage to the ferromagnetic environment. Simulation results show that for the air and ferromagnetic environments, the average output power improvement of the VREH with the middle magnet reaches 33.89% and 61.6%, respectively. A fabricated prototype is tested using the high-speed railway bearing testing machine. The influence of the impedance matching circuit and the coil connection on the VREH is investigated with the rotating speed varying from 600 r min−1 to 1800 r min−1. An energy management and storage circuit is designed and fabricated to test the energy conversion performance of the proposed harvester. Under the impedance matched condition, the optimal root mean square (RMS) output power is of 72.13–414.86 mW. It is shown that the proposed electromagnetic harvester is capable of collecting the rotational energy in the ferromagnetic environment and can be used for the high-speed smart bearing applications.
Josephson junctions with chiral p-wave ferromagnetic superconductor reservoirs in presence of spin-orbit coupling interaction
Authors: Shomali Zahra 
Published: March 2022

Abstract
The spin transfer torque (STT), is studied in new cases of Josephson junctions containing triplet p-wave chiral ferromagnetic superconductor (FS) reservoirs. To be more precise, FS1|spin orbit coupling layer (SOC1)|Normal metal (N)|SOC2|FS2 materials have been investigated. Specifically, FS1|N|FS2 structure with one layer of SOC at FS1|N interface and also two layers of SOC at both FS1|N and N|FS2 interfaces are investigated. For the structures including two SOC layers, both symmetric and asymmetric cases with respectively equal and different potential strengths are studied. The ballistic Josephson junctions are studied solving the Bogoliubov–de-Gennes equation. In particular, the cases with short normal metal contacts with thickness much smaller than the superconducting coherence length, ψ, are studied. It is obtained for the case with only one SOC layer, while the absolute value of the out-of-plane STT remains almost unchanged, its direction reverses for lower values of α, the angle between exchange fields of the two FSs. Also, the nanosystem in presence of two similar SOCs, exhibits lower out-of-plane STT. This is justified as the unit vector along the interface normal for the SOC1 is in the opposite direction of the second SOC2 layer. Hence, one can expect that these potentials fade the effect of each other. When the SOCs are not the same and have different values of potential strength, the out-of-plane STT reduces less which is attributed to slighter cancellation due to unequal potential strength. Moreover, the barrier strength is varied. It has been shown that the barrier strength increment changes the behavior of the STT. Particularly, it is found that it results in sign and value change of the STT. Further, the emergence of in-plane STTs in presence of SOC are confirmed and investigated for various systems.
Predicting speech intelligibility from a selective attention decoding paradigm in cochlear implant users
Authors: Nogueira Waldo , Dolhopiatenko Hanna 
Published: March 2022

Abstract

Objectives. Electroencephalography (EEG) can be used to decode selective attention in cochlear implant (CI) users. This work investigates if selective attention to an attended speech source in the presence of a concurrent speech source can predict speech understanding in CI users. Approach. CI users were instructed to attend to one out of two speech streams while EEG was recorded. Both speech streams were presented to the same ear and at different signal to interference ratios (SIRs). Speech envelope reconstruction of the to-be-attended speech from EEG was obtained by training decoders using regularized least squares. The correlation coefficient between the reconstructed and the attended (

ρ

A

SIR

)

or the unattended

ρ

U

SIR

speech stream at each SIR was computed. Additionally, we computed the difference correlation coefficient at the same

(

ρ

Diff

=

ρ

A

SIR

−

ρ

U

SIR

)

and opposite SIR (

ρ

DiffOpp

=

ρ

A

SIR

−

ρ

U

−

SIR

)

.

ρ

Diff

compares the attended and unattended correlation coefficient to speech sources presented at different presentation levels depending on SIR. In contrast,

ρ

DiffOpp

compares the attended and unattended correlation coefficients to speech sources presented at the same presentation level irrespective of SIR. Main results. Selective attention decoding in CI users is possible even if both speech streams are presented monaurally. A significant effect of SIR on

ρ

A

SIR

,

ρ

Diff

and ρ
DiffOpp, but not on

ρ

U

SIR

, was observed. Finally, the results show a significant correlation between speech understanding performance and

ρ

A

SIR

as well as with

ρ

U

SIR

across subjects. Moreover, ρ
DiffOpp which is less affected by the CI artifact, also demonstrated a significant correlation with speech understanding. Significance. Selective attention decoding in CI users is possible, however care needs to be taken with the CI artifact and the speech material used to train the decoders. These results are important for future development of objective speech understanding measures for CI users.
An adaptive closed-loop ECoG decoder for long-term and stable bimanual control of an exoskeleton by a tetraplegic
Authors: Moly Alexandre , Costecalde Thomas , Martel Félix , Martin Matthieu , Larzabal Christelle , Karakas Serpil , Verney Alexandre , Charvet Guillaume , Chabardes Stephan , Benabid Alim Louis , Aksenova Tetiana 
Published: March 2022

Abstract

Objective. The article aims at addressing 2 challenges to step motor brain-computer interface (BCI) out of laboratories: asynchronous control of complex bimanual effectors with large numbers of degrees of freedom, using chronic and safe recorders, and the decoding performance stability over time without frequent decoder recalibration. Approach. Closed-loop adaptive/incremental decoder training is one strategy to create a model stable over time. Adaptive decoders update their parameters with new incoming data, optimizing the model parameters in real time. It allows cross-session training with multiple recording conditions during closed loop BCI experiments. In the article, an adaptive tensor-based recursive exponentially weighted Markov-switching multi-linear model (REW-MSLM) decoder is proposed. REW-MSLM uses a mixture of expert (ME) architecture, mixing or switching independent decoders (experts) according to the probability estimated by a ‘gating’ model. A Hidden Markov model approach is employed as gating model to improve the decoding robustness and to provide strong idle state support. The ME architecture fits the multi-limb paradigm associating an expert to a particular limb or action. Main results. Asynchronous control of an exoskeleton by a tetraplegic patient using a chronically implanted epidural electrocorticography (EpiCoG) recorder is reported. The stable over a period of six months (without decoder recalibration) eight-dimensional alternative bimanual control of the exoskeleton and its virtual avatar is demonstrated. Significance. Based on the long-term (>36 months) chronic bilateral EpiCoG recordings in a tetraplegic (ClinicalTrials.gov, NCT02550522), we addressed the poorly explored field of asynchronous bimanual BCI. The new decoder was designed to meet to several challenges: the high-dimensional control of a complex effector in experiments closer to real-world behavior (point-to-point pursuit versus conventional center-out tasks), with the ability of the BCI system to act as a stand-alone device switching between idle and control states, and a stable performance over a long period of time without decoder recalibration.
An automated method for precise axon reconstruction from recordings of high-density micro-electrode arrays
Authors: Buccino Alessio Paolo , Yuan Xinyue , Emmenegger Vishalini , Xue Xiaohan , Gänswein Tobias , Hierlemann Andreas 
Published: March 2022

AbstractObjective:Neurons communicate with each other by sending action potentials (APs) through their axons. The velocity of axonal signal propagation describes how fast electrical APs can travel. This velocity can be affected in a human brain by several pathologies, including multiple sclerosis, traumatic brain injury and channelopathies. High-density microelectrode arrays (HD-MEAs) provide unprecedented spatio-temporal resolution to extracellularly record neural electrical activity. The high density of the recording electrodes enables to image the activity of individual neurons down to subcellular resolution, which includes the propagation of axonal signals. However, axon reconstruction, to date, mainly relies on manual approaches to select the electrodes and channels that seemingly record the signals along a specific axon, while an automated approach to track multiple axonal branches in extracellular action-potential recordings is still missing.Approach:In this article, we propose a fully automated approach to reconstruct axons from extracellular electrical-potential landscapes, so-called ‘electrical footprints’ of neurons. After an initial electrode and channel selection, the proposed method first constructs a graph based on the voltage signal amplitudes and latencies. Then, the graph is interrogated to extract possible axonal branches. Finally, the axonal branches are pruned, and axonal action-potential propagation velocities are computed.Main results:We first validate our method using simulated data from detailed reconstructions of neurons, showing that our approach is capable of accurately reconstructing axonal branches. We then apply the reconstruction algorithm to experimental recordings of HD-MEAs and show that it can be used to determine axonal morphologies and signal-propagation velocities at high throughput.Significance:We introduce a fully automated method to reconstruct axonal branches and estimate axonal action-potential propagation velocities using HD-MEA recordings. Our method yields highly reliable and reproducible velocity estimations, which constitute an important electrophysiological feature of neuronal preparations.
TEPX as a high-precision luminosity detector for CMS at the HL-LHC
Authors: Haranko M. , Auzinger G. 
Published: March 2022

Abstract
The CMS BRIL project upgrades its instrumentation for the Phase-2 detector to provide high-precision luminosity and beam-induced background measurements. A part of the CMS Inner Tracker — the Tracker Endcap Pixel Detector (TEPX) — will allocate a fraction of the read-out bandwidth for luminometry. The implications of the proposed approach are highlighted. A dedicated luminosity trigger and clock distribution system is introduced and a test implementation on a demonstrator system is described. A demonstrator of the real-time on-FPGA pixel cluster counting algorithm is also described.
Development of a Standing Equine Leg CT (slCT)
Authors: Moliner L. , Bolas N. , Pallas E. , Rodríguez-Álvarez M.J. , Benlloch J.M. 
Published: March 2022

Abstract
All horse ridden disciplines result in stresses to both bony and soft tissue structures. Many competitive horses experience extreme forces on the structures of the lower limb whilst executing transitions such as a tight turns or rapid acceleration. Lameness subsequent to distal limb injury is common to both the performance and pleasure horse, resulting in time out of ridden work at best or career ending at worst. In this context, Hallmarq Veterinary Imaging Ltd (a company dedicated to veterinary imaging) and the Institute of Instrumentation for Molecular Imaging (i3M) established a collaboration in order to develop a CT prototype device for the examination of horse limbs. The Standing Equine Leg CT (slCT) is an additional tool for equine veterinarians to fully evaluate and diagnose lameness, fracture and disease in the equine distal limb.
Snakes combine vertical and lateral bending to traverse uneven terrain
Authors: Fu Qiyuan , Astley Henry C , Li Chen 
Published: March 2022

Abstract
Terrestrial locomotion requires generating appropriate ground reaction forces which depend on substrate geometry and physical properties. The richness of positions and orientations of terrain features in the 3D world gives limbless animals like snakes that can bend their body versatility to generate forces from different contact areas for propulsion. Despite many previous studies of how snakes use lateral body bending for propulsion on relatively flat surfaces with lateral contact points, little is known about whether and how much snakes use vertical body bending in combination with lateral bending in 3D terrain. This lack had contributed to snake robots being inferior to animals in stability, efficiency, and versatility when traversing complex 3D environments. Here, to begin to elucidate this, we studied how the generalist corn snake traversed an uneven arena of blocks of random height variation five times its body height. The animal traversed the uneven terrain with perfect stability by propagating 3D bending down its body with little transverse motion (11° slip angle). Although the animal preferred moving through valleys with higher neighboring blocks, it did not prefer lateral bending. Among body-terrain contact regions that potentially provide propulsion, 52% were formed by vertical body bending and 48% by lateral bending. The combination of vertical and lateral bending may dramatically expand the sources of propulsive forces available to limbless locomotors by utilizing various asperities available in 3D terrain. Direct measurements of contact forces are necessary to further understand how snakes coordinate 3D bending along the entire body via sensory feedback to propel through 3D terrain. These studies will open a path to new propulsive mechanisms for snake robots, potentially increasing the performance and versatility in 3D terrain.