bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distributed state estimation of interconnected power systems with time‐varying disturbances and random communication link failures
Authors: Wang Wenle , Liu Xinrui , Wu Zequn , Li Yushuai , Guo Zhiwei , Sun Qiuye 
Published: December 2024

AbstractState estimation of multi‐area interconnected power systems is crucial for reflecting system operations and guiding actuator responses. However, sensor faults, communication link failures, and external random disturbances can inevitably lead to power system failures. Therefore, designing a highly effective state estimation method capable of timely and accurate detection of sensor faults in the power grid to mitigate losses is of significant practical importance. This paper addresses the fault estimation problem in multi‐area power systems with parameter uncertainties and proposes a fault‐tolerant state estimator that accounts for communication link failures between network layers in each area. These communication link failures are modelled as Bernoulli‐distributed variables. State estimation is achieved using information from adjacent power system areas. Sufficient conditions for the error system's performance are provided using Lyapunov stability theory and linear matrix inequality methods. Finally, simulations on a three‐area interconnected power system validate the proposed method's effectiveness in mitigating the effects of communication link failures and random disturbances. The method accurately and rapidly estimates sensor faults and the system state, ensuring stable operation and enhancing grid reliability.
Transfer morphological features for segmentation with few labels on fluorescent mitochondria images
Authors: Zhang Tianyi , Fan Junchao , Bi Xiuli , Li Weisheng , Xiao Bin , Huang Xiaoshuai 
Published: December 2024

AbstractAutomated segmentation of mitochondria is crucial for statistical analysis in biological research. Existing segmentation techniques often face challenges with fluorescence images. Handcrafted methods have poor segmentation results while deep learning‐based methods lack the labeled mitochondrial data. However, although the number of labeled mitochondrial images is limited, the unlabeled fluorescent data is easy to obtain. The authors aim to leverage a large amount of unlabeled data to learn mitochondrial morphological features. The approach begins with self‐supervised learning from a vast set of unlabeled images through masked image modeling. This technique involves presenting images with randomly masked patches, prompting the model to predict the content of these masked areas. By doing so, the model learns the distinctive features of mitochondria. In the subsequent phase, the trained encoder is transferred to the segmentation task, replacing the original reconstruction decoder with the Segformer segmentation decoder. The model is then fine‐tuned using a small labeled dataset. By reconstructing mitochondria in the masked regions, the model learns features more effectively on unlabeled samples, and improves segmentation performance even with limited labeled data. Empirical results validate the effectiveness of the approach, showing an 11.8% improvement in Intersection over Union metrics compared to existing fluorescence mitochondrial segmentation techniques.
An adaptive lucky imaging method for turbulence‐degraded image restoration
Authors: Lv Pin , Shi Tiezhu , Den Dongping , Wang Mengdi , Liu Qian , Wu Guofeng 
Published: December 2024

AbstractWhen capturing distant targets, the video sequence images are affected by atmospheric turbulence, resulting in distortion and blur. In order to restore the degraded images due to atmospheric turbulence in video sequences, this article combines lucky imaging with generative adversarial networks for the first time. The idea of lucky imaging is employed to eliminate geometric distortions, followed by the use of generative adversarial networks to address the blur issue. Additionally, an adaptive restoration method targeting turbulence intensity is proposed to improve the computational efficiency of the proposed approach. Experimental results demonstrate that the combined restoration method of lucky imaging and generative adversarial networks outperforms classical lucky imaging. Specifically, compared to classical lucky imaging, the Brenner gradient function, Laplacian gradient function, Spatial Median Difference (SMD), Entropy, Energy gradient function, PIQE, and Brisque indicators improve by 7.7%, 13.1%, 3.6%, 4.1%, 2.1%, 26.6% and 21.54% (all evaluation indicators in the above improvement rates have undergone logarithmic transformation), respectively. Meanwhile, the proposed adaptive restoration method can improve efficiency by 28%, with greater efficiency gains observed with larger datasets.
A dual‐input dual‐output high step‐up DC‐DC converter with high efficiency
Authors: Karimi Kamran , Maalandish Mohammad , Azmoon‐Asmarood Saeed , Hosseini Seyed Hossein 
Published: December 2024

AbstractHere, a new ultra step‐up DC‐DC converter with a high voltage conversion ratio is proposed. The proposed topology is a dual input dual output structure with different output voltages, which makes it suitable for use in hybrid energy systems as well as supplying the traction motor in electric vehicles. The proposed converter can provide high voltage gain with a low duty cycle compared to other multi‐port converters. The lack of a transformer and coupled inductor not only makes the final volume of the suggested converter and manufacturing costs lower, but it also does not have the problems caused by the leakage inductance of the transformer. In addition, the average voltage stress on power semiconductors of the suggested topology is low. The proposed converter follows a simple switching pattern where all power switches are switched simultaneously with a gate pulse. Operation principles, voltage and current stress passing through the semiconductor elements, RMS current values of elements, and design considerations of the proposed converter are discussed in detail. Finally, experimental results of a 250 W laboratory prototype with 96.1% efficiency are used to validate the theoretical analysis.
Non-local thermodynamic equilibrium (NLTE) abundances of europium (Eu) for a sample of metal-poor stars in the galactic halo and metal-poor disk with 1D and 〈3D〉 models
Authors: Guo Yanjun , Storm Nicholas , Bergemann Maria , Lian Jianhui , Alexeeva Sofya , Li Yangyang , Ezzeddine Rana , Jeffrey Gerber , Chen XueFei 
Published: December 2024

Context. As a key to chemical evolutionary studies, the distribution of elements in galactic provides a wealth of information to understand the individual star formation histories of galaxies. The r-process is a complex nucleosynthesis process, and the origin of r-process elements is heavily debated. Europium (Eu) is viewed as an almost pure r-process element. Accurate measurements of europium abundances in cool stars are essential for an enhanced understanding of the r-process mechanisms.
Aims. We measure the abundance of Eu in solar spectra and a sample of metal-poor stars in the Galactic halo and metal-poor disk, with the metallicities ranging from −2.4 to −0.5 dex, using non-local thermodynamic equilibrium (NLTE) line formation. We compare these measurements with Galactic Chemical Evolution (GCE) models to explore the impact of the NLTE corrections on the contribution of r-process site in Galactic chemical evolution.
Methods. In this work, we used NLTE line formation, as well as one-dimensional (1D) hydrostatic and spatial averages of three-dimensional hydrodynamical (<3D>) model atmospheres to measure the abundance of Eu based on both the Eu II 4129 Å and Eu II 6645 Å lines for solar spectra and metal-poor stars.
Results. We find that for Eu II 4129 Å line the NLTE modeling leads to higher (0.04 dex) solar Eu abundance in 1D and higher (0.07 dex) in <3D> NLTE while NLTE modeling leads to higher (0.01 dex) solar Eu abundance in 1D and lower (0.03 dex) in <3D> NLTE for Eu II 6645 Å line. Although the NLTE corrections for the Eu II λ 4129 Å and Eu II λ 6645 Å lines are opposite, the discrepancy between the abundances derived from these individual lines reduces after applying NLTE corrections, highlighting the critical role of NLTE abundance determinations. By comparing these measurements with Galactic chemical evolution (GCE) models, we find that the amount of NLTE correction does not require significant change of the parameters for Eu production in GCE models.
Trajectories of hospital service use in the last 12 months of life by people with chronic kidney disease: a retrospective cohort study
Authors: Okuba Tolesa , Sa Zhisheng , Badgery-Parker Tim , Long Janet C. , Braithwaite Jeffrey , Makris Angela , Hutton Annie , Levesque Jean-Frederic , Watson Diane E. , Westbrook Johanna I. , Mitchell Rebecca 
Published: December 2024

Objective This study aimed to examine group-based trajectories of hospital service use by people with chronic kidney disease (CKD) in the last 12 months of life. Methods A retrospective cohort study was conducted using hospital admission and mortality data in New South Wales, Australia. Individuals aged ≥18 years who were hospitalised during 2014–2021 and who died during 2015–2021 were included. A group-based trajectory analysis was conducted including all-cause admissions and unplanned-only admissions. Multinomial logistic regression examined predictors of trajectory group membership. Results There were 10,653 adults who had at least one CKD hospital admission 12 months prior to death. Four group-based trajectories of hospital service use were identified for all-cause admissions (i.e. Very-Low, Low, Moderate, High) and three group-based trajectories for unplanned-only admissions (i.e. Low, Moderate, High). The study identified associations between frequent hospitalisations and key patient characteristics and health conditions. Individuals in the High hospitalisation group were more likely to have cancer (OR 4.55; 95% CI: 2.54–8.16). Additionally, the High unplanned hospitalisation group showed increased likelihoods of being adults aged 18–64 years (OR 1.94; 95% CI: 1.32–2.84) and having diagnosis of congestive heart failure (OR 1.80; 95% CI: 1.26–2.55), cancer (OR 2.25; 95% CI: 1.49–3.40), mental disorders (OR 1.88; 95% CI: 1.35–2.62) or smoking (OR 2.01; 95% CI: 1.49–2.70) compared with the Low hospitalisation group. Conclusions Group-based trajectory analysis revealed specific patterns in hospital service usage. Understanding these patterns helps in devising targeted strategies to decrease unplanned hospitalisations among these high-risk patients.
Key comparison BIPM.RI(I)-K7 of the air-kerma standards of the PTB, Germany, and the BIPM in mammography x-rays
Authors: Kessler C , Burns D , Pojtinger S 
Published: December 2024

Main text
A new key comparison has been made between the air-kerma standards of the PTB, Germany, and the BIPM in mammography x-ray beams. The results show the standards to agree at the level of the expanded uncertainty of the comparison of 7.2 parts in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database.
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Interplay of Kitaev Interaction and Off-Diagonal Exchanges: Exotic Phases and Quantum Phase Diagrams
Authors: Luo 罗 Qiang 强 , Zhao 赵 Jize 继泽 , Wang 王 Xiaoqun 孝群 
Published: December 2024

Abstract
Aligning with the ongoing search for quantum spin liquids (QSLs), identifying QSLs in Kitaev magnets has attracted significant research interest during the past decade. Nevertheless, it remains a significant challenge. One of the major difficulties is that Kitaev QSL is typically fragile to competing interactions such as off-diagonal exchanges, which are ubiquitous in real materials owing to spin-orbit coupling and crystal-field effects. This, in turn, generates many intriguing field-induced novel phases and the thermal Hall effect. In this review, we focus on the interplay between the Kitaev interaction and off-diagonal Γ and Γ′ exchange from a numerical perspective. The review discusses certain representative exotic phases such as Γ spin liquid, nematic ferromagnet, spin-flop phase, and distinct chiral spin states with spontaneous time-reversal symmetry breaking. It also presents quantum phase diagrams of anisotropic Kitaev-Γ chains that exhibit kaleidoscopy for both ordered and disordered phases.
Dynamical symmetry restoration in the Heisenberg spin chain
Authors: Rylands Colin , Vernier Eric , Calabrese Pasquale 
Published: December 2024

Abstract
The entanglement asymmetry is an observable independent tool to investigate the relaxation of quantum many-body systems through the restoration of an initially broken symmetry of the dynamics. In this paper we use this to investigate the effects of interactions on quantum relaxation in a paradigmatic integrable model. Specifically, we study the dynamical restoration of the U(1) symmetry corresponding to rotations about the z-axis in the XXZ model quenched from a tilted ferromagnetic state. We find two distinct patterns of behaviour depending upon the interaction regime of the model. In the gapless regime, at roots of unity, we find that the symmetry restoration is predominantly carried out by bound states of spinons of maximal length. The velocity of these bound states is suppressed as the anisotropy is decreased toward the isotropic point leading to slower symmetry restoration. By varying the initial tilt angle, one sees that symmetry restoration is slower for an initially smaller tilt angle, signifying the presence of the quantum Mpemba effect. In the gapped regime, however, spin transport for non maximally tilted states is dominated by smaller bound states with longer bound states becoming frozen. This leads to much longer time scales for restoration compared to the gapless regime. In addition, the quantum Mpemba effect is absent in the gapped regime.
Numerical Investigation of Heat Transfer Characteristics for Various CPU Designs
Authors: Lal Milind , Surabhi N G , Srikanth N S 
Published: December 2024

Abstract
Due to the rise in demand of computers with high computing power, there is significant advancement in electronic components inside the CPU cabinet every 6 months. The life of these electronic components is greatly affected by their working temperatures. Therefore, it is necessary to maintain the temperature of these devices within acceptable limits. Forced air cooling inside the CPU cabinet is a widely used technique for this purpose. Heat sinks are another way of increasing the heat transfer rate. The present study analyses the effect of different probable improvement cases implemented in the basic CPU cabinet. These improvement cases include changing the position and number of fans, changing the type of heat sink, and changing the inlet cross section. By making use of commercially available CFD softwares like Ansys Fluent and Icepak, the cooling effect in the CPU cabinet is analysed.
A Review on methylene blue degradation activities of various transition metal oxides nanocomposites
Authors: Seema S , Bhatt Praveen , Meenakshi  , Sharma Rajesh 
Published: December 2024

Abstract
In recent time, the major issue faced by the society is to get clean water for the drinking purpose. One of the most common chemical that renders water unsafe for drinking is industrial dyes. Out of so many dyes, Methylene Blue (MB) dye is the one that is used in textiles causing dye effluent contamination. It is non-biodegradable, poisonous and carcinogenic which is hazardous for environment and human health. Therefore, it is necessary to create an effective, environmentally acceptable method of removing MB from wastewater. Nowadays, metal oxides-based semiconductor is used as a photo catalyst for removing organic dye in wastewater. But their photocatalytic efficiency is constrained due to large forbidden gap and large recombination time of electron hole pairs. Thus, researchers continuously worked to improve the degradation efficiency using a dopant or by forming nanocomposites. Therefore, in the current review article, the synthesis method of metal oxide (MO) nanoparticles and their photocatalytic efficiency toward MB dye have been discussed.
Kaehlerian Projective Recurrent Manifolds of Umbilical Hypersurface
Authors: Sulochana  , Negi U. S. , Chauhan Preeti 
Published: December 2024

Abstract
Murgescu (1970) explored generalized weyl spaces, while Negi (2017) Investigated Kaehlerian conharmonic bi-recurrent spaces. Subsequently, Negi (2018) delved into hyper asymptotic curves on Kaehlerian hypersurfaces. In this current work, the author computes Kaehlerian projective recurrent manifolds of umbilical hypersurfaces with a comprehensive weyl conharmonic recurrent curvature tensor and the projective recurrent curvature tensor.
Convergence analysis of Periodic Functions in Hölder Class
Authors: Dumka Diksha , Sharma Kusum , Sahani S.K. , Sharma Garima 
Published: December 2024

Abstract
Abundant research have been carried out to calculate the inaccuracy between the input and output signals. Singh [2] defined the Hölder’s i.e. H
ω space and approximated the functions belonging to this space through (C, 1)(E, 1) i.e. the product of (C, 1) and (E, 1) mean. In this article, we first introduce the triple product transform i.e. (N, pn
)(C, 1)(E, 1) and establish a result on approximation of signals in H
ω space via conjugate of Fourier series.
Numerical analysis of heat and mass transport of hybrid nanofluid over a nonlinear stretchable sheet with magnetic field in presence of Soret and dufour Effect
Authors: Jat Kavita , Sharma Kalpna , Soni Pooja , Choudhary Prasun 
Published: December 2024

Abstract
The study investigates the consequence of Soret and Dufour effects on magnetohydrodynamic hybrid nanofluid flow past a nonlinear stretchable sheet. Hybrid nanofluids, a new type of conventional fluid, are found to enhance boundary layer heat transfer compared to conventional nanofluids. Water serves as base fluid with copper and aluminium oxide nanoparticles. The analysis utilizes the Darcy-Forchheimer flow near a nonlinearly passable stretched surface, incorporating nonlinear heat radiation. Through similarity conversion and the bvp4c method, numerical solutions are obtained. Parametric studies reveal the influence of various physical parameters, with graphical representations illustrating fluid parameter variations. Numerical interpretations include coefficients of surface drag, heat flux, and mass flux. The study shows that the Dufour effect significantly benefits heat exchange in hybrid nanofluids, while the Soret number indicates alterations in solute diffusivity with temperature changes. Also, it is noted that high resistance offered by local inertia coefficient causes an increase in the skin’s friction.
On the Free Vibration of 3D-Printed Structural Elements
Authors: Virgin Lawrie 
Published: December 2024

Abstract
This paper focuses on using 3D-printing to produce relatively simple, flexible structural components such as cantilevers, rings and plane frames. The relatively high resolution of modern 3D-printers facilitates the production of small-scale but slender structures, and thus provides an opportunity to exploit geometric parameter variations to enhance a practical understanding of stiffness and vibration. This approach has proved successful in both the classroom via demonstration models, as well as in the research lab in which elementary facilities can be utilized to acquire data. An especially useful facet of this approach is the assessment and justification for modeling simplifications, e.g., estimating flexural modulus, or judging the circumstances under which the familiar sway assumption is valid in portal frames. Non-simple structural geometries, for example circular rings, can also be conveniently produced and tested for natural frequencies and vibration mode shapes. We then extend this approach to forced vibration, with examples including the vibrating reed tachometer and sympathetic resonance. The advantage of this approach obviates the need for any external sources of excitation.
Experimental analysis of the electromagnetic damper of a non-ideal system revisited
Authors: Petrocino E A , Balthazar J M , GonÇalves P J P , Silveira M , Tusset A M , Ribeiro M A 
Published: December 2024

Abstract
The use of limited power motors fixed to flexible structures is widely used in engineering and has seen a significant increase in published studies. These components form a non-ideal system, which can cause undesirable phenomena throughout its execution, such as the capture of parametric oscillation by resonance, studied by Sommerfeld, whose effect bears his name. One study, on a vibration absorber in a non-ideal system, was done in Petrocino et al., Meccanica, v. 58, n. 1, p. 287-302, 2023, on a model that represents a fixed beam and at the free end a motor with its unbalanced shaft. In this work, based on the equations that govern the movement, an analytical development was carried out, using the average method, to obtain an approximate solution and numerical simulations with the absorber on and off. The results demonstrated a reduction in parametric excitation, an effect caused by the electromagnetic absorber. Based on the parameters of this revisited work, a prototype was built to carry out experimental tests. A beam was fixed at one end and at the free end a DC motor was fixed with an unbalance on its axis, a magnet fixed at the free end immersed in the core of a coil as a damping actuator. When the motor is accelerated, it causes a parametric excitation in the beam and is captured by resonance, where the damping action is evident. The results of the tests were compared with the results of the models from the revisited work, validating the performance of the passive electromagnetic vibration absorber.
Signal analysis for drone detection and characterization using acoustic radar
Authors: Zakaria N A Z , Mohd Rozaimi F N S , Enche Ab Rahim S A , Khan Z I 
Published: December 2024

Abstract
In response to the growing use of drones, this paper focuses on developing a radar-based drone detection system, emphasizing the challenges and opportunities of the Acoustic Radar method. The research addresses the critical challenge of accurately detecting drones to protect sensitive areas and facilities. By tackling the limitations of current drone detection methods, such as optical surveillance, and addressing challenges related to limited datasets, this research innovates analysis for accurate and reliable drone detection and characterization. The methodology involves data acquisition, signal processing using MATLAB, and signal analysis. The system configuration includes wired microphones attached to a tripod and connected to a laptop for data processing and display, set up in an outdoor environment to minimize interference. Quantitative insights are derived through mean and standard deviation calculations, guided by predefined targets reflecting amplitude variations based on drone size and distance. To address the challenge of surrounding sound noise, the system implements digital filters to enhance detection accuracy. The results underscore the effectiveness of the proposed Acoustic Radar method in advancing algorithms for accurate and reliable drone detection and characterization.