bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transformer fault diagnosis method based on SMOTE and NGO-GBDT
Authors: Wang Li-zhong , Chi Jian-fei , Ding Ye-qiang , Yao Hai-yan , Guo Qiang , Yang Hai-qi 
Published: March 2024

AbstractIn order to improve the accuracy of transformer fault diagnosis and improve the influence of unbalanced samples on the low accuracy of model identification caused by insufficient model training, this paper proposes a transformer fault diagnosis method based on SMOTE and NGO-GBDT. Firstly, the Synthetic Minority Over-sampling Technique (SMOTE) was used to expand the minority samples. Secondly, the non-coding ratio method was used to construct multi-dimensional feature parameters, and the Light Gradient Boosting Machine (LightGBM) feature optimization strategy was introduced to screen the optimal feature subset. Finally, Northern Goshawk Optimization (NGO) algorithm was used to optimize the parameters of Gradient Boosting Decision Tree (GBDT), and then the transformer fault diagnosis was realized. The results show that the proposed method can reduce the misjudgment of minority samples. Compared with other integrated models, the proposed method has high fault identification accuracy, low misjudgment rate and stable performance.
Impact toughness and dynamic constitutive model of geopolymer concrete after water saturation
Authors: Yan Tiecheng , Yin Xiangxiang , Zhang Xingyuan 
Published: March 2024

AbstractThe dynamic compression test of geopolymer concrete (GC) before and after water saturation was carried out by the split Hopkinson pressure bar (SHPB). And the effects of water saturation and strain rate on impact toughness of GC were studied. Based on Weibull statistical damage distribution theory, the dynamic constitutive model of GC after water saturation was constructed. The results show that the dynamic peak strain and specific energy absorption of GC have strain rate strengthening effect before or after water saturation. The impact toughness of GC decreases after water saturation. The size distribution of GC fragments has fractal characteristics, and the fractal dimension of GC fragments after water saturation is smaller than that before water saturation. The dynamic constitutive model based on Weibull statistical damage distribution theory can accurately describe the impact mechanical behavior of GC after water saturation, and the model fitting curves are in good agreement with the experimental stress–strain curves.
New evidence on the real role of digital economy in influencing public health efficiency
Authors: Zhao Xiongfei , Wu Shansong , Yan Bin , Liu Baoliu 
Published: March 2024

AbstractIn recent years, the rapid advancement of digital technology has supported the growth of the digital economy. The transformation towards digitization in the public health sector serves as a key indicator of this economic shift. Understanding how the digital economy continuously improves the efficiency of public health services and its various pathways of influence has become increasingly important. It is essential to clarify the impact mechanism of the digital economy on public health services to optimize health expenditures and advance digital economic construction. This study investigates the impact of digital economic development on the efficiency of public health services from a novel perspective, considering social media usage and urban–rural healthcare disparities while constructing a comprehensive index of digital economic development. The findings indicate that the digital economy reduces the efficiency of public health services primarily through two transmission mechanisms: the promotion of social media usage and the widening urban–rural healthcare gap. Moreover, these impacts and transmission pathways exhibit spatial heterogeneity. This study unveils the intrinsic connection and mechanisms of interaction between digital economic development and the efficiency of public health services, providing a theoretical basis and reference for government policy formulation. However, it also prompts further considerations on achieving synergy and interaction between the digital economy and public health services.
Microcirculation-driven mitochondrion dysfunction during the progression of experimental sepsis
Authors: Fejes Roland , Rutai Attila , Juhász László , Poles Marietta Zita , Szabó Andrea , Kaszaki József , Boros Mihály , Tallósy Szabolcs Péter 
Published: March 2024

AbstractSepsis is accompanied by a less-known mismatch between hemodynamics and mitochondrial respiration. We aimed to characterize the relationship and time dependency of microcirculatory and mitochondrial functions in a rodent model of intraabdominal sepsis. Fecal peritonitis was induced in rats, and multi-organ failure (MOF) was evaluated 12, 16, 20, 24 or 28 h later (n = 8/group, each) using rat-specific organ failure assessment (ROFA) scores. Ileal microcirculation (proportion of perfused microvessels (PPV), microvascular flow index (MFI) and heterogeneity index (HI)) was monitored by intravital video microscopy, and mitochondrial respiration (OxPhos) and outer membrane (mtOM) damage were measured with high-resolution respirometry. MOF progression was evidenced by increased ROFA scores; microcirculatory parameters followed a parallel time course from the 16th to 28th h. Mitochondrial dysfunction commenced with a 4-h time lag with signs of mtOM damage, which correlated significantly with PPV, while no correlation was found between HI and OxPhos. High diagnostic value was demonstrated for PPV, mtOM damage and lactate levels for predicting MOF. Our findings indicate insufficient splanchnic microcirculation to be a possible predictor for MOF that develops before the start of mitochondrial dysfunction. The adequate subcellular compensatory capacity suggests the presence of mitochondrial subpopulations with differing sensitivity to septic insults.
A redescending M-estimator approach for outlier-resilient modeling
Authors: Raza Aamir , Noor-ul-Amin Muhammad , Ayari-Akkari Amel , Nabi Muhammad , Usman Aslam Muhammad 
Published: March 2024

AbstractThe OLS model is built on the assumption of normality in the distribution of error terms. However, this assumption can be easily violated, especially when there are outliers in the data. A single outlier can disrupt the normality assumption of error terms, making the OLS model less effective. In such situations, M-estimators (MEs) come into play to obtain reliable estimates. We introduce a redescending M-estimators (RME) for robust regression to handle datasets with outliers. The proposed RME produces more robust estimates by effectively managing the influence of outliers, even at lower values of the tuning constant. We compared the performance of this estimator with existing RMEs using real-life data examples and an extensive simulation study. The results show that our suggested RME is more efficient than the compared ME in various situations.
Compaction and compressibility characteristics of snail shell ash and granulated blast furnace slag stabilized local bentonite for baseliner of landfill
Authors: Fadugba Olaolu George , Adeniran Julius Kayode , Alaneme George Uwadiegwu , Oluyemi-Ayibiowu Bamitale Dorcas , Omomomi Oladapo Jayejeje , Adetukasi Adesola Olayinka 
Published: March 2024

AbstractThis study comprehensively explores the compaction and compressibility characteristics of snail shell ash (SSA) and ground-granulated blast-furnace slag (GBFS) in stabilizing local bentonite for landfill baseliner applications. The untreated soil, with a liquid limit of 65%, plastic limit of 35%, and plasticity index of 30%, exhibited optimal compaction at a moisture content of 32% and a maximum dry density of 1423 kg/m3. SSA revealed a dominant presence of 91.551 wt% CaO, while GBFS contained substantial 53.023 wt% SiO2. Treated samples with 20% GBFS and 5% SSA exhibited the highest maximum dry density (1561 kg/m3) and optimal moisture content (13%), surpassing other mixtures. The 15% SSA-treated sample demonstrated superior strength enhancement, reaching an unconfined compressive strength of 272.61 kPa over 28 days, while the 10% GBFS-treated sample achieved 229.95 kPa. The combination of 15% SSA exhibited the highest shear strength (49 kPa) and elastic modulus (142 MPa), showcasing robust mechanical properties. Additionally, the 15% SSA sample displayed favourable hydraulic conductivity (5.57 × 10–8 cm/s), outperforming other mixtures. Notably, the permeability test, a critical aspect of the study, was meticulously conducted in triplicate, ensuring the reliability and reproducibility of the reported hydraulic conductivity values. Treated samples with SSA and GBFS showed reduced compressibility compared to the control soil, with the 15% SSA-treated sample exhibiting a more consistent response to applied pressures. Scanning Electron Microscopy analysis revealed substantial composition changes in the 15% SSA mixture, suggesting its potential as an effective base liner in landfill systems. In conclusion, the 15% SSA sample demonstrated superior mechanical properties and hydraulic conductivity, presenting a promising choice for landfill liner applications.
Upper holocene tephro-chronostratigraphy of Irazú Volcano, Costa Rica
Authors: Campos-Durán Daniela , Alvarado Guillermo E. , Martí Joan 
Published: March 2024

AbstractIrazú is one of the largest and most active volcanoes in Costa Rica. We present the tephro-chronostratigraphy of the last 2.6 ka of the Irazú volcano based on detailed field work and C14 radiometric dating, as well as a revision of the geological and historical records. In the stratigraphic record we identified at least 30 tephra units. Eight of them corresponding to the historical period (i.e., after 1700 A.D.), separated by repose periods of different durations. The distribution of the deposits, the volcanic morphologies (craters and pyroclastic cones) and the radiometric ages indicate that most of this recent eruptive activity has occurred from the summit of Irazú along an E–W fissure (~ 4 km long). Toward the west of the summit, near the Sapper hill may be the source of the oldest eruptions at 200 A.D., while the La Laguna cone, located to the east of the summit, could have formed around 1540 A.D., and Main Crater to the west could have formed around sixteenth–seventeenth century. Since then, the historical eruptions (i.e., 1723–1724, 1917–1921, 1924, 1928, 1930, 1933, 1939–1940 and 1963–1965) have been sourced from this crater, but not all of them are registered in the stratigraphy. The eruption frequency of Irazú during this period ranges from 23 to 100 years, with a major event about every 80 years. Irazu’s eruptions have been mainly phreatomagmatic and Strombolian, including some phreatic explosions. We present a detailed tephro-chronostratigraphy that will help to building temporal analysis for hazard assessment and risk management plans to face future eruptions at Irazú.
A mud budget of the Wadden Sea and its implications for sediment management
Authors: Colina Alonso Ana , van Maren Dirk Sebastiaan , Oost Albert Peter , Esselink Peter , Lepper Robert , Kösters Frank , Bartholdy Jesper , Bijleveld Allert Imre , Wang Zheng Bing 
Published: March 2024

AbstractThe world’s coasts and deltas are progressively threatened by climate change and human activities. The degree at which coastlines can adapt to these changes strongly depends on the sediment availability. The availability of muddy sediments is however poorly known. This study aims at developing a mud budget for the world’s largest system of uninterrupted tidal flats: the Wadden Sea. The resulting mud budget is nearly closed: ~ 12 million ton/year enters the system on its western end, ~ 1.5 million ton/year is added by local rivers, while ~ 12 million ton annually deposits or is extracted by anthropogenic activities. A mud deficit already exists in the downdrift areas, which will only become more pronounced with increased sea level rise rates. Mud is thus a finite resource similar to sand, and should be treated as such in sediment management strategies. Resolving future challenges will therefore require a cross-border perspective on sediment management.
Reducing uncertainties in greenhouse gas emissions from chemical production
Authors: Cullen Luke , Meng Fanran , Lupton Rick , Cullen Jonathan M. 
Published: March 2024

AbstractUncertainties in greenhouse gas emissions estimates for petrochemical production have lacked quantification globally, impacting emissions reporting and decarbonization policymaking. Here we analyze cradle-to-gate emissions of 81 chemicals at 37,000 facilities worldwide, assessing 6 uncertainty sources. The results estimate a 34% uncertainty in total global emissions of 1.9 ± 0.6 Gt of CO2-equivalent emissions for 2020, and 15–40% uncertainties across most petrochemicals analyzed. The largest uncertainties stem from the inability to assign specific production processes to facilities owing to data limitations. Uncertain data on feedstock production and off-site energy generation contribute substantially, while on-site fuel combustion and chemical reactions have smaller roles. Allocation method choices for co-products are generally insignificant. Prioritizing facility-level process specification in data collection for just 20% of facilities could reduce global uncertainty by 80%. This underscores the necessity of quantifying uncertainty in petrochemical greenhouse gas emissions globally and outlines priorities for improved reporting. The dataset generated offers independent emissions factor estimates based on facility-specific information for 81 chemicals, supporting future analyses.
A high‐power electromagnetic source for disabling improvised explosive devices
Authors: Ariztia Laurent , Ibrahimi Njomza , Zhabin Alexey , de Ferron Antoine Silvestre , Rivaletto Marc , Martinod Edson , Bertrand Valérie , Novac Bucur , Pécastaing Laurent 
Published: March 2024

AbstractUltra‐wideband (UWB) microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter‐terrorism activity. The authors present the main findings of a research dedicated to the development of a pulsed power‐driven electromagnetic field source for disabling improvised explosive devices (IED). The pulsed power generator driving the source is a 13‐stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV, with a pulse repetition frequency (PRF) of up to 100 Hz. The generator is coupled to a bipolar pulse forming line, providing bipolar pulses with a dV/dt of around 1.6 MV/ns. This pulsed power system feeds an array composed of 16 Koshelev‐type UWB antennas through an impedance matching transformer. The resulting electromagnetic source is capable to produce pulsed electric fields (PEFs) having a figure‐of‐merit (FOM) of 1 MV. First, practical experiments were carried out to study the effects of the PEFs on targets. The targets used in the present study are M2B type flashbulbs, known to have the same susceptibility as the US army M6 detonator. Different configurations of wires (shielded, twisted, etc) with different lengths were used in connecting items inside these targets. The tests were performed by placing the flashbulbs at different distances to determine the essential parameters (i.e., amplitude, duration, and frequency range) of the PEFs required to trigger them. An overview of the experimental campaign and the main findings are also presented followed by conclusions.
Tracking the motion of a shock along a channel in the low solar corona
Authors: Rigney J. , Gallagher P. T. , Ramsay G. , Doyle J. G. , Long D. M. , Stepanyuk O. , Kozarev K. 
Published: March 2024

Context. Shock waves are excited by coronal mass ejections (CMEs) and large-scale extreme-ultraviolet (EUV) wave fronts and can result in low-frequency radio emission under certain coronal conditions.
Aims. In this work, we investigate a moving source of low-frequency radio emission as a CME and an associated EUV wave front move along a channel of a lower density, magnetic field, and Alfvén speed in the solar corona.
Methods. Observations from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, the Nançay Radio Heliograph (NRH), and the Irish Low Frequency Array (I-LOFAR) were analysed. Differential emission measure maps were generated to determine densities and Alfvén maps, and the kinematics of the EUV wave front was tracked using CorPITA. The radio sources’ positions and velocity were calculated from NRH images and I-LOFAR dynamic spectra.
Results. The EUV wave expanded radially with a uniform velocity of ∼500 km s−1. However, the radio source was observed to be deflected and appeared to move along a channel of a lower Alfvén speed, abruptly slowing from 1700 km s−1 to 250 km s−1 as it entered a quiet-Sun region. A shock wave with an apparent radial velocity of > 420 km s−1 was determined from the drift rate of the associated Type II radio burst.
Conclusions. The apparent motion of the radio source may have resulted from a wave front moving along a coronal wave guide or by different points along the wave front emitting at locations with favourable conditions for shock formation.
Turbulence and particle energization in twisted flux ropes under solar-wind conditions
Authors: Pezzi O. , Trotta D. , Benella S. , Sorriso-Valvo L. , Malara F. , Pucci F. , Meringolo C. , Matthaeus W. H. , Servidio S. 
Published: March 2024

Context.The mechanisms regulating the transport and energization of charged particles in space and astrophysical plasmas are still debated. Plasma turbulence is known to be a powerful particle accelerator. Large-scale structures, including flux ropes and plasmoids, may contribute to confining particles and lead to fast particle energization. These structures may also modify the properties of the turbulent, nonlinear transfer across scales.Aims.We aim to investigate how large-scale flux ropes are perturbed and, simultaneously, how they influence the nonlinear transfer of turbulent energy toward smaller scales. We then intend to address how these structures affect particle transport and energization.Methods.We adopted magnetohydrodynamic simulations perturbing a large-scale flux rope in solar-wind conditions and possibly triggering turbulence. Then, we employed test-particle methods to investigate particle transport and energization in the perturbed flux rope.Results.The large-scale helical flux rope inhibits the turbulent cascade toward smaller scales, especially if the amplitude of the initial perturbations is not large (∼5%). In this case, particle transport is inhibited inside the structure. Fast particle acceleration occurs in association with phases of trapped motion within the large-scale flux rope.
Magnetic helicity evolution during active region emergence and subsequent flare productivity
Authors: Sun Zheng , Li Ting , Wang Quan , Yang Shangbin , Zhang Mei , Chen Yajie 
Published: March 2024

Aims. Solar active regions (ARs), which are formed by flux emergence, serve as the primary sources of solar eruptions. However, the specific physical mechanism that governs the emergence process and its relationship with flare productivity remains to be thoroughly understood.
Methods. We examined 136 emerging ARs, focusing on the evolution of their magnetic helicity and magnetic energy during the emergence phase. Based on the relation between helicity accumulation and magnetic flux evolution, we categorized the samples and investigated their flare productivity.
Results. The emerging ARs we studied can be categorized into three types, Type-I, Type-II, and Type-III, and they account for 52.2%, 25%, and 22.8% of the total number in our sample, respectively. Type-I ARs exhibit a synchronous increase in both the magnetic flux and magnetic helicity, while the magnetic helicity in Type-II ARs displays a lag in increasing behind the magnetic flux. Type-III ARs show obvious helicity injections of opposite signs. Significantly, 90% of the flare-productive ARs (flare index ≥ 6) were identified as Type-I ARs, suggesting that this type of AR has a higher potential to become flare productive. In contrast, Type-II and Type-III ARs exhibited a low and moderate likelihood of becoming active, respectively. Our statistical analysis also revealed that Type-I ARs accumulate more magnetic helicity and energy, far beyond what is found in Type-II and Type-III ARs. Moreover, we observed that flare-productive ARs consistently accumulate a significant amount of helicity and energy during their emergence phase.
Conclusions. These findings provide valuable insight into the flux emergence phenomena, offering promising possibilities for early-stage predictions of solar eruptions.
Fusion de données géophysiques (TRE et MASW) et géotechniques (granulométrie) pour la caractérisation de digues en terre
Authors: Dezert Théo , Palma-Lopes Sérgio , Courivaud Jean-Robert , Fargier Yannick , Vergniault Christophe 
Published: March 2024

La bonne caractérisation des ensembles lithologiques des digues en terre constitue un enjeu majeur dans un contexte de prévention de rupture d’ouvrage. En effet, les conséquences d’un tel événement peuvent s’avérer potentiellement catastrophiques (pertes humaines, graves impacts environnementaux et économiques). Les méthodologies reconnues pour caractériser les digues en terre comprennent classiquement des méthodes de reconnaissance géophysiques et géotechniques de natures complémentaires. Ce travail de recherche présente une méthodologie de fusion permettant la combinaison de données issues de ces deux types de sources d’information. Ici, les données utilisées proviennent d’une campagne de reconnaissance menée sur une digue de canal EDF. Les résultats obtenus ont été préalablement publiés et présentés sous forme d’un article de revue internationale à comité de lecture. Cette campagne de terrain regroupe trois types d’informations : résistivités électriques, vitesses d’ondes de cisaillement et analyses granulométriques d’échantillons. La méthodologie de fusion introduite repose sur le cadre théorique des masses de croyance. Tout en tenant compte des spécificités de chaque méthode (répartition spatiale, imprécisions et incertitudes des données), cette approche de fusion permet de quantifier le niveau de conflit entre les sources d’information ainsi que d’associer un indice de confiance aux caractérisations proposées. Les résultats de la fusion obtenus, dans le cadre du cas d’étude présenté, mettent en évidence la capacité de cette méthodologie à discriminer les unités lithologiques (remblais fins ou grossiers avec brèches calcaires, socle marneux ou calcaire) ainsi qu’à localiser les positions d’interfaces entre unités et les niveaux de confiance associés. Ces résultats sont en cohérence avec les connaissances déjà disponibles sur le contexte géologique du site et mettent en évidence l’intérêt de combiner des informations issues de sources de nature différente afin de tirer profit de leur complémentarité. Ces travaux ont montré un potentiel prometteur pour cette méthode, tant sur une digue de canal que sur une levée. Ils seront poursuivis par une étude comparative de différentes méthodes de fusion et par la mise en application sur de nouveaux cas réels d’études.