bluuebunny/crossref_metadata_2025_split huggingface dataset:
Viscous damping of tremor using a wearable robot with an optimized mechanical metamaterial
Authors: Raghavendra Kulkarni Suhas , Accoto Dino , Campolo Domenico 
Published: December 2024

Abstract
Pathological tremors can often be debilitating to activities of daily living and significantly affect the quality of life. Such tremulous movements are commonly observed in wrist flexion-extension (FE). To suppress this tremor we present a wearable robot (WR) with a customized mechanical metamaterial (MM) as the physical human-robot interface (pHRI). The MM is optimized to conform to the user’s wrist posture and follow the hand’s Cartesian trajectory. This is done to minimize the shear between the pHRI and the user’s skin and consequently improve wearability. This WR is then used to effect a viscous tremor suppression using the velocity of the user’s wrist FE. We present a model for the interaction between the WR and the user with which we develop the viscous damping approach for tremor. This is then evaluated in simulation and using a dedicated test bed. This tremor suppression approach demonstrates an attenuation of 20–30 dB at various tremulous frequencies resulting in significantly lower tremor amplitudes due to the viscous damping.
Intermediate Fluence Downward Terrestrial Gamma Ray Flashes as Observed by the Telescope Array Surface Detector
Authors: Abbasi R. U. , Kieu N. , Krehbiel P. R. , Belz J.W. , Saba M. M. F. , Rison W. , Stanley M. A. , Rodeheffer D. , Mazzucco D. , Knight T. , da Silva D. R. , Cruz I. T. , Remington J. , Mazich J. , LeVon R. , Smout K. , Petrizze A. , Mattos E. , Abu‐Zayyad T. , Allen M. , Arimura R. , Barcikowski E. , Bergman D. R. , Blake S. A. , Buckland I. , Cheon B. G. , Chikawa M. , Fujii T. , Fujisue K. , Fujita K. , Fujiwara R. , Fukushima M. , Furlich G. , Globus N. , Gonzalez R. , Hanlon W. , Hayashida N. , He H. , Hibino K. , Higuchi R. , Honda K. , Ikeda D. , Inoue N. , Ishii T. , Ito H. , Ivanov D. , Iwakura H. , Iwasaki A. , Jeong H. M. , Jeong S. , Jui C. C. H. , Kadota K. , Kakimoto F. , Kalashev O. , Kasahara K. , Kasami S. , Kawakami S. , Kawata K. , Kharuk I. , Kido E. , Kim H. B. , Kim J. H. , Kim J. H. , Kim S. W. , Kimura Y. , Komae I. , Kubota Y. , Kuznetsov M. , Kwon Y. J. , Lee K. H. , Lubsandorzhiev B. , Lundquist J. P. , Matsuyama T. , Matthews J. N. , Mayta R. , Myers I. , Nagataki S. , Nakai K. , Nakamura R. , Nakamura T. , Nakazawa A. , Nishio E. , Nonaka T. , Ogio S. , Ohnishi M. , Ohoka H. , Oku Y. , Okuda T. , Omura Y. , Ono M. , Oshima A. , Ozawa S. , Park I. H. , Potts M. , Pshirkov M. S. , Rodriguez D. C. , Rott C. , Rubtsov G. I. , Ryu D. , Sagawa H. , Sakaki N. , Sako T. , Sakurai N. , Seki T. , Sekino K. , Shah P. D. , Shibasaki Y. , Shibata N. , Shibata T. , Shikita J. , Shimodaira H. , Shin B. K. , Shin H. S. , Shinto D. , Smith J. D. , Sokolsky P. , Stokes B. T. , Stroman T. A. , Takahashi K. , Takamura M. , Takeda M. , Takeishi R. , Taketa A. , Takita M. , Tameda Y. , Tanaka K. , Tanaka M. , Thomas S. B. , Thomson G. B. , Tinyakov P. , Tkachev I. , Tomida T. , Troitsky S. , Tsunesada Y. , Udo S. , Uehama T. , Urban F. , Warren D. , Wong T. , Yamamoto M. , Yamazaki K. , Yashiro K. , Yoshida F. , Zhezher Y. , Zundel Z. 
Published: December 2024

AbstractOn 11 September 2021, two small thunderstorms developed over the Telescope Array Surface Detector (TASD) that produced an unprecedented number of six downward terrestrial gamma ray flashes (TGFs) within one‐hour timeframe. The TGFs occurred during the initial stage of negative cloud‐to‐ground flashes whose return strokes had increasingly large peak currents up to 223 kA, 147 GeV energy deposit in up to 25 1.2 km‐spaced surface detectors, and intermittent bursts of gamma‐rays with total durations up to 717 s. The analyses are based on observations recorded by the TASD network, complemented by data from a 3D lightning mapping array, broadband VHF interferometer, fast electric field change sensor, high‐speed video camera, and the National Lightning Detection Network. The TGFs of the final two flashes had gamma fluences of and 8, logarithmically bridging the gap between previous TASD and satellite‐based detections. The observations further emphasize the similarity between upward and downward TGF varieties, suggesting a common mechanism for their production.
Péclet‐Number‐Dependent Longitudinal Dispersion in Discrete Fracture Networks
Authors: Yin Tingchang , Man Teng , Zhang Pei , Galindo‐Torres Sergio Andres 
Published: December 2024

AbstractDispersion in fractured media impacts many environmental and geomechanical practices. It is mainly controlled by the structure of fracture networks and the Péclet number , but predicting it remains challenging. In this study, numerous three‐dimensional stochastic discrete fracture networks (DFNs) were generated, where the density, size, and orientation vary significantly. The aperture and conductivity are proportional to the size, following power‐laws. Through flow and transport simulation, we evaluated the longitudinal dispersion coefficients . We found that, as density increases, the tortuosity decreases and the first passage time distributions approximate bell‐shaped curves more closely, which suggests, but does not fully guarantee, that an asymptotic dispersion regime may emerge for denser DFNs, as solute particles traverse more fractures and the macroscopic inter‐fracture mixing is more homogeneous. We then determined the values for DFNs in which the time evolution of the variance of particle displacements becomes linear and hence asymptotic. The results show that both and fracture density affect , but the former has a much stronger influence than the latter. A new Péclet number was recalculated for all DFNs, where the characteristic length scale accounts for the influence of large fractures. Dimensionless values show a unique power‐law relationship with high values. Furthermore, when advection dominates, the dimensionless can be described by a universal finite‐size scaling function depending on fracture density and domain sizes. The findings of this study enhance the understanding of transport in fracture networks and imply the potential for predicting in a broad range of scenarios using statistics on fracture parameters obtainable at the field scale.
Chemical Evolution of R-process Elements in Stars (CERES)
Authors: Lombardo L. , Hansen C. J. , Rizzuti F. , Cescutti G. , Mashonkina L. I. , François P. , Bonifacio P. , Caffau E. , Alencastro Puls A. , Fernandes de Melo R. , Gallagher A. J. , Skúladóttir Á. , Koch-Hansen A. J. , Sbordone L. 
Published: December 2024

Context. The chemical abundances of elements such as barium and the lanthanides are essential to understand the nucleosynthesis of heavy elements in the early Universe as well as the contribution of different neutron capture processes (for example slow versus rapid) at different epochs.
Aims. The Chemical Evolution of R-process Elements in Stars (CERES) project aims to provide a homogeneous analysis of a sample of metal-poor stars ([Fe/H]<−1.5) to improve our understanding of the nucleosynthesis of neutron capture elements, in particular the r-process elements, in the early Galaxy.
Methods. Our data consist of a sample of high resolution and high signal-to-noise ratio UVES spectra. The chemical abundances were derived through spectrum synthesis, using the same model atmospheres and stellar parameters as derived in the first paper of the CERES series.
Results. We measured chemical abundances or upper limits of seven heavy neutron capture elements (Ba, La, Ce, Pr, Nd, Sm, and Eu) for a sample of 52 metal-poor giant stars. We estimated through the mean shift clustering algorithm that at [Ba/H]=−2.4 and [Fe/H]=−2.4 a variation in the trend of [X/Ba], with X=La,Nd,Sm,Eu, versus [Ba/H] occurs. This result suggests that, for [Ba/H]<−2.4, Ba nucleosynthesis in the Milky Way halo is primarily due to the r-process, while for [Ba/H]>−2.4 the effect of the s-process contribution begins to be visible. In our sample, stars with [Ba/Eu] compatible with a Solar System pure r-process value (hereafter, r-pure) do not show any particular trend compared to other stars, suggesting r-pure stars may form in similar environments to stars with less pure r-process enrichments.
Conclusions. Homogeneous investigations of high resolution and signal-to-noise ratio spectra are crucial for studying the heavy elements formation, as they provide abundances that can be used to test nucleosynthesis models as well as Galactic chemical evolution models.
Dissecting the disk and the jet of a massive (proto)star
Authors: Cesaroni R. , Galli D. , Padovani M. , Rivilla V. M. , Sánchez-Monge Á. 
Published: December 2024

Context. The study of disks around early-type (proto)stars has recently been boosted by a new generation of instruments, and additional evidence has been found of disk+jet systems around stars of up to ~20 M⊙. These results appear to confirm theoretical predictions that even the most massive stars may form though disk-mediated accretion.
Aims. We want to investigate one of the best examples of disk+jet systems around an early B-type (proto)star, IRAS 20126+4104. The relatively simple structure of this object and its relative proximity to Earth (1.64 kpc) make it an ideal target for resolution of its disk and the determination of its physical and kinematical structure.
Methods. Despite the high declination of IRAS 20126+4104, it has been possible to perform successful observations with the Atacama Large Millimeter and submillimeter Array at 1.4 mm in the continuum emission and a number of molecular tracers of high-density gas (for the disk) and shocked gas (for the jet).
Results. The new data allow us to improve on previous similar observations of IRAS 20126+4104 and confirm the existence of a Keplerian accretion disk around a ~12 M⊙ (proto)star. From methyl cyanide, we derived the rotation temperature and column density as a function of disk radius. We also obtained a map of the same quantities for the jet using the ratio between two lines of formaldehyde. We also use two simple models of the jet and the disk to estimate the basic geometrical and kinematical parameters of the two. From the temperature and column density profiles, we conclude that the disk is stable at all radii. We also estimate an accretion rate of ~10−3 M⊙ yr−1.
Conclusions. Our analysis confirms that the jet from IRAS 20126+4104 is highly collimated, lies close to the plane of the sky, and expands with velocity increasing with distance. As expected, the gas temperature and column density peak in the bow shock. The disk is undergoing Keplerian rotation but a non-negligible radial velocity component is also present that is equal to ~40% of the rotational component. The disk is slightly inclined with respect to the line of sight and has a dusty envelope that absorbs the emission from the disk surface. This causes a slight distortion of the disk structure observed in high-density tracers such as methyl cyanide. We also reveal a significant deviation from axial symmetry in the SW part of the disk, which might be caused by either tidal interaction with a nearby, lower-mass companion or interaction with the outflowing gas of the jet.
Die Effekte von „Medical Flossing“ auf das statische und dynamische
Gleichgewicht bei Athlet*innen
Authors: Limpach Sam 
Published: December 2024

ZusammenfassungDie sportliche Leistung zu verbessern und die Häufigkeit an Verletzungen der
unteren Extremitäten zu verringern, ist für Sportler*innen und ihr
Betreuungspersonal von großer Bedeutung. Daher spielt die
Gleichgewichtskontrolle, insbesondere die Sprunggelenk-Propriozeption, eine
unbestreitbare Rolle.Medical Flossing könnte aufgrund ihrer theoretischen biomechanischen Mechanismen
eine zeitweilige Verbesserung der Gleichgewichtskontrolle bewirken. Die
Forschung zu möglichen Einflüssen von Flossing auf die Gleichgewichtskontrolle
ist jedoch spärlich.In der vorliegenden Studie wurden die unmittelbaren Effekte von Flossing am
Sprunggelenk in Kombination mit einer gewichtsbelastenden Bewegungsübung auf das
statische und dynamische einbeinige Gleichgewicht untersucht. Vierzig gesunde
Sportstudent*innen (Alter 22,12±3,04) wurden nach dem Zufallsprinzip einer
Interventions- oder Kontrollgruppe zugeteilt. Beide Gruppen führten 3 Sätze von
10 erhöhten einbeinigen Wadenhebern durch. In der Interventionsgruppe wurde das
Sprunggelenk während der Übung mit Flossing-Band umwickelt. Der Vor- und
Nachtest bestand aus 4 Gleichgewichtsaufgaben mit unterschiedlichen Untergründen
(stabil, instabil) und Bewegungen (statisch, dynamisch). Die wichtigste
abhängige Variable war die Standardabweichung des „Center of Pressure“ in
anterior-posteriorer und medio-lateraler Richtung, gemessen mit einer
Kraftmessplatte.Die Ergebnisse zeigten keinen signifikanten Unterschied der
Gleichgewichtskontrolle der beiden Gruppen bei den statischen
Gleichgewichtsaufgaben. Allerdings führten beide Gruppen die dynamischen
Aufgaben in der anterior-posterioren Richtung während des Post-Tests besser aus.
Die medio-laterale Richtung der dynamischen Aufgaben führte zu einer
signifikanten Abnahme (p=0,044) der Gleichgewichtskontrolle in der
Interventionsgruppe in Bezug auf die Interaktion Untergrund*Gruppe.Die Ergebnisse dieser Studie deuten darauf hin, dass eine einmalige
Flossing-Anwendung das einbeinige Gleichgewicht bei gesunden Sportstudent*innen
nicht verbessert. Außerdem wurde eine Abnahme der Gleichgewichtskontrolle in
medio-lateraler Richtung festgestellt.
Nonvascular Renal Interventions: A Review and Procedural Considerations for the Interventional Radiologist
Authors: Kumari Divya 
Published: December 2024

AbstractInterventional radiology plays a vital role in performing noninvasive, nonvascular genitourinary interventions. This article discusses practical aspects of the biopsy technique using the cortical tangential approach for native and transplant kidneys. Additionally, the indications, contraindications, and procedure details of the nephrostomy tube and nephroureteral placement will be reviewed.
A near spurious-free 6 GHz laterally-excited bulk acoustic resonator with single-sided wavy electrodes
Authors: Yang Sijie , Liu Wenjuan , Wen Zhiwei , Xie Ying , Tong Xin , Liu Yan , Cai Yao , Guo Shishang , Sun Chengliang 
Published: December 2024

Abstract
Laterally excited bulk wave resonators demonstrate outstanding electromechanical coupling coefficient (K
eff
2) suitable for the design of wideband filters. However, it has not been commercialized due to the spurious modes and low temperature coefficient of frequency (TCF). In this paper, a near spurious-free 6 GHz resonator (SW-BAR) is proposed with single-sided wavy edges in the aperture direction. The SW-BAR suppress high-order harmonics in the area of the electrodes by confining the formation of standing waves. The design is fabricated using a 316 nm Z-cut lithium niobate thin film with an 18 μm pitch (P). Measurements of the fabricated devices feature the spurious-free A1 mode with a high resonance frequency (f
s) of 5.932 GHz, K
eff
2 of 22.19%, and Bode_Q
max of 283. In addition, the TCF of the proposed structure has improved from −73.58 to −57.36 ppm °C−1 since the suppression of high-order harmonics at f
s. The near spurious-free SW-BAR shows fascinating prospects for high-performance RF filters in 5G/6G communication.
Three-color high-sensitivity thermometry using infrared laser absorption spectroscopy of NO
Authors: Zhang Lin , Jia Wanting , Sun Jiachen , Shao Jiankun 
Published: December 2024

Abstract
A novel three-color high-sensitivity thermometry method is proposed, providing more accurate temperature measurements for nitrogen-containing fuel reactive flows. This method determines temperature by simultaneously sweeping three absorption peaks of NO. A relationship between absorbance and temperature was established with parameters determined from shock tube experiments from 1100 to 2200 K. To evaluate its performance, six sets of NO absorption spectra data at various temperatures were collected. The results demonstrate that the three-color thermometry achieves an average absolute error of 7 K, significantly lower than the two-color thermometry’s average absolute errors of 16 and 20 K. This three-color thermometry methods offers higher sensitivity and accuracy, making it a practical solution for measuring temperatures during the combustion of nitrogen-containing fuels.
Cross-domain fault diagnosis using convolutional attention network with an improved dung beetle optimization algorithm
Authors: Li Zihang , Luo Xiong , Peng Qiaojuan , Yang Yuandong 
Published: December 2024

Abstract
Rotating machinery plays a critical role in large-scale equipment, and its operational condition significantly influences the stability and safety of the equipment. Therefore, it is imperative to improve the accuracy of fault diagnosis. While deep learning has been widely utilized for fault diagnosis, the effectiveness of the model heavily relies on hyperparameter configuration. Current deep learning methods often necessitate human intervention to fine-tune these hyperparameters, leading to a time-consuming and potentially subjective process. Furthermore, although various meta-heuristic algorithms have been employed for optimizing hyperparameters, these methods are computationally intensive and susceptible to converging on local optimal solutions when dealing with high-dimensional non-convex hyperparameter spaces. To tackle this issue, this paper proposes a cross-domain fault diagnosis using convolutional attention network (CAN) with an improved dung beetle optimization (IDBO) algorithm, called IDBO-CAN algorithm. Firstly, an IDBO algorithm is designed, which mainly uses chaotic local search, levy flight strategy and adaptive lognormal distribution variation to enhance the global optimization capability of the dung beetle optimization algorithm. Secondly, the setting of hyperparameters significantly affects the performance of the CAN using a one-dimensional convolutional neural network. The IDBO algorithm is employed to automatically determine better hyperparameters for CAN. Finally, the performance of IDBO and IDBO-CAN algorithms are evaluated by 13 benchmark functions and multi-source datasets. The experimental results show that IDBO and IDBO-CAN algorithms have excellent performance on many benchmark functions and datasets.
Research on fault component extraction and fault type identification of rotating machinery based on MDSM and a novel convolutional neural network
Authors: Liu Zhilei , Ning Dayong , Zhou Cheng , Geng Jianhua , Liang Gangda , Zhang Fengrui , Hou Jiaoyi 
Published: December 2024

Abstract
Given the complexity and difficulty in extracting and recognizing multi-axis mechanical fault components, a method for fault extraction and identification based on the multi-Axis displacement superposition method (MDSM) and a novel convolutional neural network (NCNN) is proposed. In the proposed MDSM method, first, correlation analysis is used to determine the operational status of the mechanical system and to identify the location of faults in the multi-axis rotating mechanical system. Secondly, a simplified initial point selection process is introduced to segment the collected fault component. Subsequently, a signal superposition method with position offset correction is employed to perform position correction and superposition operations on the segmented signals, enhancing the accuracy of the fault signal. Finally, the front end of the superimposed signals is extracted as the fault component, completing the separation and extraction of the fault components. For the extracted fault signals, an NCNN is designed for fault-type identification. NCNN improves computational efficiency and effectively completes fault feature identification through a lightweight network architecture and a nonlinear learning rate scheduling strategy. The results of the experiment show that the proposed method can accurately determine the fault occurrence location, extract the fault components, and achieve high-accuracy fault type identification.
A model for Andreev reflection induced by d-wave superconductivity in graphene nanoribbons
Authors: Takagaki Y 
Published: December 2024

Abstract
An approximate method for implementing the d-wave superconductivity in the tight-binding lattice model for graphene is proposed. A real-space pair potential having the d-wave symmetry is derived by regarding the honeycomb lattice as a multi-component rectangular system consisting of four sublattices. The reliability of the method is tested for a strip of the conventional square lattice, where the approximation is found to work well for lower-lying transverse modes. Unexpectedly, the validity excels for all the modes in the limit of the infinitely large superconducting energy gap as well as for the zero gap. Remarkable dependencies of the quantized wavenumbers on the inclination of the d-wave symmetry is thereby revealed. The Andreev reflection induced by the d-wave superconductor is reproduced by the modified method for the square lattice as long as the superconducting energy gap is small. The quasiparticle propagation at finite excitation energies, however, cannot be treated reliably when the superconductivity is introduced in armchair graphene nanoribbons (NRs), i.e. a half of the NR is normal-conducting and the other half is superconducting. The restriction of the applicability for the honeycomb lattice originates primarily from the point that the hopping between the lattice sites is not fully mirror-symmetrical.
Exposing the role of silica nanoparticles and fiber stacking in mechanical, water absorption, and bio-degradation behaviors of banana-papaya hybrid composites
Authors: Kedarnath M P , Ramasamy N , Anand M Dev , Raj J Bensam 
Published: December 2024

Abstract
Natural fiber composites are becoming more valuable in industries due to their eco-friendliness, high strength-to-weight ratio, and cost-effectiveness. This study aimed to develop and evaluate hybrid composites made from banana and papaya fibers, enhanced with silica nanoparticles, bonded with epoxy resin, to assess the effects of fiber layering sequence and silica content on their mechanical, water absorption, and biodegradation properties. Tri-layer composites with configurations such as BPB (Banana-Papaya-Banana) and PBP (Papaya-Banana-Papaya) were fabricated using the hand layup technique. Mechanical testing revealed that PBP composites exhibited superior tensile strength, which further improved when reinforced with silica nanoparticles (SiO2) in various concentrations. The PBP composite with 2 wt% SiO2 displayed optimal performance, showing tensile strength (83 MPa), flexural strength (104 MPa), impact strength (8.4 kJ m−2), and hardness (86 Shore-D) due to effective silica dispersion, enhancing load transfer and interfacial bonding. Thermal stability was also improved by the silica, making this composite suitable for high-temperature applications. Additionally, PBP/3 wt% SiO2 exhibited low water absorption (8% at 15 days) and minimal mass loss (14% at 60 days), highlighting its resistance to environmental degradation, which is essential for humid or marine environments. The PBP/2 wt% SiO2 composite is recommended for use in industries like automotive, manufacturing, and structural engineering, where its high mechanical properties, durability, and eco-friendliness make it a promising alternative to synthetic composites, thus supporting sustainable practices.