bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-technique based coarse to fine form registration for ultra-precision diamond milling of freeform optics
Authors: Wu Panyue , Guo Pan , Xiong Zhiwen , Dong Zengwen , Zhang Shaojian 
Published: October 2024

Abstract
Due to its excellent optical performance, freeform optics has found extensive applications into sophisticated optical systems. Ultra-precision diamond milling (UPDM) offers an advanced solution for manufacturing high-quality freeform optics with sub-micrometric form error. However, its varying curvature characteristics would lead to uneven residual and inconsistent surface quality. Therefore, to improve the registration process accuracy, this study proposes a multi-technique based coarse to fine form registration for UPDM of freeform optics and it provides a benchmark for evaluating the form error of machined surfaces. Firstly, two-dimensional Fourier transform and Pearson correlation coefficient were used for area coarse registration. Next, singular value decomposition was utilized to transform the coordinate systems for fine registration. Then, simulations were performed to construct two representative freeform optics-light emitting diode lens and virtual reality lens-and their forms were registered. Finally, the form error between the designed and measured surfaces was discussed in UPDM experiments. The results revealed that the proposed form registration method demonstrated strong robustness and accuracy under various errors. After registering simulation, the peak to valley and root mean square deviations between the designed surface and the measured surface of the two types of freeform optics were both less than 10−7 μm. Significantly, this study applies advanced mathematical tools in the form registration and thus improves the precision and efficiency of form registration in freeform optics.
Research on noise reduction method of centrifugal pump coupling fault signal based on LMD-FE-IWT
Authors: Houlin Liu , Xiao Li , Wen Xu , Haochen Ma , Liang Dong 
Published: October 2024

Abstract
Aiming at the problem that the coupling fault signal of centrifugal pump presents the complexity of mutual coupling due to the mutual influence of various fault components, and it is easy to be affected by the surrounding environmental noise, which leads to the difficulty of noise reduction, the LMD-FE-IWT noise reduction method is proposed. This method first utilizes local mean decomposition (LMD) to adaptively decompose the vibration signal, and calculates the fuzzy entropy of each component. According to fuzzy entropy, the components are divided into two categories: disordered and ordered. After the improved wavelet threshold denoising of the disordered component, it is reconstructed with the ordered component to achieve the denoising effect. By analying the simulation signal and experimental data, the results show that, the proposed method outperforms other methods, with improvements in signal-to-noise ratio by 55.95%, 48.86%, and 31.71% for the simulation signal noise reduction. The effect is significant, enabling the effective extraction of characteristic frequencies associated with different faults for the experimental signal noise reduction.
Room-temperature infrared photoluminescence and broadband photodetection characteristics of Ge/GeSi islands on silicon-on-insulator
Authors: Singh Sudarshan , John John Wellington , Sarkar Arijit , Dhyani Veerendra , Das Samaresh , Ray Samit K 
Published: October 2024

Abstract
In this study, molecular beam epitaxial growth of strain-driven three-dimensional self-assembled Ge/GeSi islands on silicon-on-insulator (SOI) substrates, along with their optical and photodetection characteristics, have been demonstrated. The as-grown islands exhibit a bimodal size distribution, consisting of both Ge and GeSi alloy islands, and show significant photoluminescence (PL) emission at room temperature, specifically near optical communication wavelengths. Additionally, these samples were used to fabricate a Ge/GeSi islands/Si nanowire based phototransistor using a typical e-beam lithography process. The fabricated device exhibited broadband photoresponse characteristics, spanning a wide wavelength range (300–1600 nm) coupled with superior photodetection characteristics and relatively low dark current (∼ tens of pA). The remarkable photoresponsivity of the fabricated device, with a peak value of ∼11.4 A W−1 (λ ∼ 900 nm) in the near-infrared region and ∼1.36 A W−1 (λ ∼ 1500 nm) in the short-wave infrared (SWIR) region, is a direct result of the photoconductive gain exceeding unity. The room-temperature optical emission and outstanding photodetection performance, covering a wide spectral range from the visible to the SWIR region, showcased by the single layer of Ge/GeSi islands on SOI substrate, highlight their potential towards advanced applications in broadband infrared Si-photonics and imaging. These capabilities make them highly promising for cutting-edge applications compatible with complementary metal-oxide-semiconductor technology.
Using Arduino to study two-degree-of-freedom mass-spring system
Authors: Escudero Raquel , Barrere Nicasio , Rodríguez Chialanza Mauricio 
Published: October 2024

Abstract
The study of oscillations is one of the topics included in undergraduate-level physics courses. This work demonstrates the use of ultrasound sensors and Arduino boards to study coupled oscillations. According to the configuration presented, it is possible to study the motion depending on the system’s initial conditions. This system allows students to expand the possibility of experiments.
MFCA-MICNN: a convolutional neural network with multiscale fast channel attention and multibranch irregular convolution for noise removal in dMRI
Authors: Ai Lingmei , Shi Yunfan , Yao Ruoxia , Li Liangfu 
Published: October 2024

Abstract
Diffusion magnetic resonance imaging (dMRI) currently stands as the foremost noninvasive method for quantifying brain tissue microstructure and reconstructing white matter fiber pathways. However, the inherent free diffusion motion of water molecules in dMRI results in signal decay, diminishing the signal-to-noise ratio (SNR) and adversely affecting the accuracy and precision of microstructural data. In response to this challenge, we propose a novel method known as the Multiscale Fast Attention-Multibranch Irregular Convolutional Neural Network for dMRI image denoising. In this work, we introduce Multiscale Fast Channel Attention, a novel approach for efficient multiscale feature extraction with attention weight computation across feature channels. This enhances the model’s capability to capture complex features and improves overall performance. Furthermore, we propose a multi-branch irregular convolutional architecture that effectively disrupts spatial noise correlation and captures noise features, thereby further enhancing the denoising performance of the model. Lastly, we design a novel loss function, which ensures excellent performance in both edge and flat regions. Experimental results demonstrate that the proposed method outperforms other state-of-the-art deep learning denoising methods in both quantitative and qualitative aspects for dMRI image denoising with fewer parameters and faster operational speed.
Imaging error reduction in radial cine-MRI with deep learning-based intra-frame motion compensation
Authors: Sui Zhuojie , Palaniappan Prasannakumar , Paganelli Chiara , Kurz Christopher , Landry Guillaume , Riboldi Marco 
Published: October 2024

Abstract

Objective. Radial cine-MRI allows for sliding window reconstruction at nearly arbitrary frame rate, promising high-speed imaging for intra-fractional motion monitoring in magnetic resonance guided radiotherapy. However, motion within the reconstruction window may determine the location of the reconstructed target to deviate from the true real-time position (target positioning errors), particularly in cases of fast breathing or for anatomical structures affected by the heartbeat. In this work, we present a proof-of-concept study aiming to enhance radial cine-MR imaging by implementing deep-learning-based intra-frame motion compensation techniques. Approach. A novel network (TransSin-UNet) was proposed to continuously estimate the final-position image of the target, corresponding to end of the frame acquisition. Within the radial k-space reconstruction window, the spatial–temporal dependencies among the sinogram representation of the spokes were modeled by a transformer encoder subnetwork, followed by a UNet subnetwork operating in the spatial domain for pixel-level fine-tuning. By simulating motion-dependent radial sampling with (tiny) golden angles, we generated datasets from 25 4D digital anthropomorphic lung cancer phantoms. The network was then trained and extensively evaluated across datasets characterized by varying azimuthal radial profile increments. Main Results. The method required additional 4.8 ms per frame over the conventional approach involving direct image reconstruction with motion-corrupted spokes. TransSin-UNet outperformed architectures relying solely on transformer encoders or UNets across all the comparative evaluations, leading to a noticeable enhancement in image quality and target positioning accuracy. The normalized root mean-squared error decreased by 50% from the initial value of 0.188 on average, whereas the mean Dice similarity coefficient of the gross tumor volume increased from 85.1% to 96.2% in the investigated cases. Furthermore, the final-positions of anatomical structures undergoing substantial intra-frame deformations were precisely derived. Significance. The proposed approach enables an effective intra-frame motion compensation, offering an opportunity to reduce errors in radial cine-MR imaging for real-time motion management.
Study of modulation in complex refractive indices induced by ultrafast relativistic electrons using infrared and THz probe pulses
Authors: Jeong Diana , Bark Hyeon Sang , Kim Yushin , Shin Junho , Kim Hyun Woo , Oang Key Young , Jang Kyu-Ha , Lee Kitae , Jeong Young Uk , Baek In Hyung , Levin Craig S 
Published: October 2024

Abstract

Objective. Achieving ultra-precise temporal resolution in ionizing radiation detection is essential, particularly in positron emission tomography, where precise timing enhances signal-to-noise ratios and may enable reconstruction-less imaging. A promising approach involves utilizing ultrafast modulation of the complex refractive index, where sending probe pulses to the detection crystals will result in changes in picoseconds (ps), and thus a sub—10 ps coincidence time resolution can be realized. Towards this goal, here, we aim to first measure the ps changes in probe pulses using an ionizing radiation source with high time resolution. Approach. We used relativistic, ultrafast electrons to induce complex refractive index and use probe pulses in the near-infrared (800 nm) and terahertz (THz, 300 µm) regimes to test the hypothesized wavelength-squared increase in absorption coefficient in the Drude free-carrier absorption model. We measured BGO, ZnSe, BaF2, ZnS, PBG, and PWO with 1 mm thickness to control the deposited energy of the 3 MeV electrons, simulating ionization energy of the 511 keV photons. Main results. Both with the 800 nm and THz probe pulses, transmission decreased across most samples, indicating the free carrier absorption, with an induced signal change of 11% in BaF2, but without the predicted Drude modulation increase. To understand this discrepancy, we simulated ionization tracks and examined the geometry of the free carrier distribution, attributing the mismatch in THz modulations to the sub-wavelength diameter of trajectories, despite the lengths reaching 500 µm to 1 mm. Additionally, thin samples truncated the final segments of the ionization tracks, and the measured initial segments have larger inter-inelastic collision distances due to lower stopping power (dE/dx) for high-energy electrons, exacerbating diffraction-limited resolution. Significance. Our work offers insights into ultrafast radiation detection using complex refractive index modulation and highlights critical considerations in sample preparation, probe wavelength, and probe-charge carrier coupling scenarios.
The effect of selenium ion concentration on zinc selenide thin films prepared by a photo-assisted chemical bath deposition method
Authors: Hile D D , Koao L F , Swart H C , Motloung S V , Ahemen I , Ndlangamandla C L 
Published: October 2024

Abstract
Zinc selenide (ZnSe) thin films were deposited on non-conducting glass substrates at different selenium concentrations using a photo-assisted chemical bath deposition method. The films were deposited for 2.0 h at 80 °C and annealed for 2.0 h at 250 °C. X-ray diffraction (XRD) revealed a hexagonal structure with preferential orientation along the (002) plane, and the crystallite sizes were about 9–11 nm. Raman scattering showed longitudinal optical phonon modes due to the ZnSe, and the effect of the selenium concentration was noticed on the peak intensities of the XRD and Raman scattering studies. Optical analysis showed higher absorbance in the visible region than near the infrared spectrum, making the thin films good materials for selective absorber surfaces. The estimated bandgap ranged between 2.37 and 2.70 eV. X-ray spectroscopy confirmed the presence of the desired elements and revealed that the ratio of selenium to zinc declined after the sample was prepared with 0.6 M selenium ions. Photoluminescence studies revealed three emission peaks, which were due to defect state levels in the ZnSe. By varying the selenium concentration, the ZnSe was tuned to a reddish color emission, as confirmed by Commission Internationale de L’Eclairage (CIE) color chromaticity analysis. The selective absorption, wide bandgap, and emission properties suggest that the material is promising for light-emitting device applications.
Design and experiment of magnetostrictive-electromagnetic hybrid floor vibration energy harvester
Authors: Liu Huifang , Wang Chao , Zhao Luyao , Chang Yunlong , Gao Yifei , Ren Teng 
Published: October 2024

Abstract
This paper proposes using a magnetostrictive-electromagnetic hybrid floor vibration energy harvester (MEHH), which employs the Villari effect and Faraday’s Law of Electromagnetic Induction. This harvester can generate three output voltages simultaneously when subjected to the same vibration source, and it can supply power to multiple microelectronic devices simultaneously, thereby enhancing the efficiency of vibrational energy harvesting. The magnetostrictive component (MH) utilizes a rod-shaped Terfenol-D as the core element. A two-stage force amplification mechanism has been incorporated to amplify and process the input force generated by the vibration source and apply it to both ends of the Terfenol-D rod to enhance energy conversion efficiency. An optimization analysis of the primary mechanism’s dimensions was conducted to determine the final optimized dimensions and obtain a force magnification of 24.01. The electromagnetic section (EH) has a permanent magnet as the core element, and the central mover, which consists of the permanent magnet, floats up and down in the axial direction inside the hollow tube. The flux density generated by different forms of central movers is simulated and studied to determine the optimal arrangement of the central movers. During the experiment, the MEHH was excited by 240 N, the peak voltage of MH output reached 2.66 V, and the maximum power generated by the matched load resistor reached 334 mW. The peak voltage of EH output reached 1.59 V, and the maximum power generated by the matched load resistor reached 45.1 mW.
Simulation and theory for wiring compaction of robot skin tactile sensor by frequency-selective triboelectric-piezoelectric filters
Authors: Ramezani Amir Hossein , Mirdamadi Hamid Reza , Salmani-Tehrani Mahdi 
Published: October 2024

Abstract
Robots are increasingly equipped with different sensors to better identify things and interact with their environment. One such sensor is the ability to sense and receive information through touch. A significant challenge in designing tactile sensors is to create a larger and more complex network of electrical connections to cover larger partitioned surface areas, necessitating a more compaction for electrical connections. In this study, we try to reduce the number of these array connections by designing a novel triboelectric-piezoelectric pressure sensors that will function as electromechanical frequency-selective filters. The sensor cell units are created in the form of various disk-shape layers with a basic double-lamina layers, a triboelectric lamina placed over a piezoelectric lamina. The triboelectric layer, being soft, is used for static pressure measurement and more sensitivity enhancement. In addition, an electromechanical frequency-selective filter is generated by altering geometric dimensions of that lamina, such as the radius and/or thickness. An applied pressure is calculated by measuring the electric current and the cell unit admittance. The advantage of using piezo-layer geometric manipulation for generating different operating resonant frequencies is that it is a simpler design task as compared to alter the cell electrical properties, which is the focus of previous research. In this work, a theoretical model and numerical simulations are employed to obtain the electromechanical admittance of a set of three unit cell tactile sensors.
Review of Yu–Shiba–Rusinov bound state in quantum impurity structures: basic principle and current progress
Authors: Wang Jia-Ning , Peng Tan , Chen Xiao-Dan , Hou Yong-Dan , Yang Jun-Tao , Shang Hao , Nan Nan , Xiong Yong-Chen , Liu Wu-Ming 
Published: October 2024

Abstract
Magnetic impurities connected to superconductors reservoir result in bound states within the superconducting gap, so called Yu–Shiba–Rusinov (YSR) state. In the past few years, this field has gained much attention since it is crucial for engineering novel superconducting many-body states, with the perspective of manufacturing Majorana Fermions. The underlying physical picture of YSR state depends closely on the form of the impurities connected to the leads, the manner in which the impurities are organized, and also the diverse local interactions, which is always disclosed with the aid of quantum impurity models. This article provides a comprehensive overview of the progress achieved by previous studies, focusing on the issues demonstrated by quantum impurity structures. The physical mechanisms and the related phenomena assisted by different interactions are discussed in detail. Furthermore, a comprehensive overview of recent experimental achievements is presented, using various metal phthalocyanine molecules as illustrative examples, thereby establishing a robust foundation for future inquiries in this domain.
Angle-resolved photoemission spectroscopy study on kagome superconductor AV3Sb5 (A = K, Rb, Cs)
Authors: Cai Yongqing , Hao Zhanyang , Wang Le , Wang Yuan , Liu Yixuan , Mei Jia-Wei , Wang Jianfeng , Chen Chaoyu 
Published: October 2024

Abstract
The recently discovered kagome superconductors AV3Sb5 (A= K, Rb, Cs) provide a new platform to explore intertwined symmetry-breaking orders. However, great controversies exist to date, including the origin of charge density wave (CDW), the unconventional or conventional nature of superconductivity, and the presence or absence of time-reversal symmetry breaking. A thorough understanding of the fundamental electronic structure is crucial for addressing these disputes. In this review, we provide an extensive summary of the key structural and electronic properties of AV3Sb5 compounds and evaluate the current research on their unconventional electronic order, especially the superconductivity and CDW, with a particular focus on insights from angle-resolved photoemission spectroscopy studies. We expect this review to be timely due to the convergence of various experimentally observed phenomena related to the CDW and superconducting order parameters in AV3Sb5 compounds. Our goal is to guide future investigations aimed at uncovering the microscopic origins of these unconventional electronic properties in kagome superconductors.
Eurasian lynx optimizer: a novel metaheuristic optimization algorithm for global optimization and engineering applications
Authors: Wang Xiaowei 
Published: October 2024

Abstract
Meta-heuristic algorithms, despite advancements, still face challenges in universally optimizing solutions across various problem domains. There is a persistent need for algorithms that can demonstrate superior performance in both theoretical benchmarks and real-world applications. This research aims to introduce a novel optimization algorithm, the Eurasian Lynx Optimizer (ELO), inspired by the adaptive hunting and survival strategies of the Eurasian lynx, targeting enhanced convergence accuracy and robustness. The ELO algorithm integrates a suite of innovative strategies mirroring the lynx's behavior, including prey pursuit, predator evasion, and adaptive movement patterns. It operates through a three-phase iterative process: exploration, exploration & exploitation, and exploitation, each utilizing distinct search mechanisms. These stages incorporate strategies like direct prey attack, enemy evasion, differential mutation, Lévy Flight, Gaussian mutation, and population consolidation. Comprehensive evaluations against ten state-of-the-art algorithms on 63 benchmark functions across CEC2014, CEC2017, and CEC2019 sets revealed that ELO achieved the best solution in 81% of cases. It consistently ranked first with averages of 1.6, 1.0, and 1.4 across respective benchmark sets, showcasing superior performance. Furthermore, ELO successfully tackled four constrained engineering design optimization problems, validating its practical utility.
Theoretical improvement of the energy conversion efficiency of an AZO/CdTe heterojunction solar cell to over 27% by incorporating FeSi2 as a second absorber layer
Authors: Medina José Carlos Zepeda , Andrés Enrique Rosendo , Espinosa Eduardo Camacho , Ruíz Crisóforo Morales , Yarce Leticia Treviño , Isasmendi Reina Galeazzi , Trujillo Román Romano , Salgado Godofredo García , Solis Antonio Coyopol 
Published: October 2024

Abstract
This paper presents the numerical analysis of cadmium telluride (CdTe) based solar cells using iron di silicide (FeSi2) as the second absorber layer and aluminum-doped zinc oxide (AZO) as the window layer. The photovoltaic performance of solar cells with Al/AZO/CdTe/FeSi2/Ni structure was analyzed and improved by SCAPS-1D software. When analyzing the influence of thickness and carrier concentration on the photovoltaic performance, it was found that the optimum values for the CdTe layer were 300 nm and 1015 cm−3, for the AZO layer they were 10 nm and 1018 cm−3, while for the FeSi2 layer they were 1 μm and 1018 cm−3. The defect density (Nt) at the AZO/CdTe and CdTe/FeSi2 interfaces was also analyzed, obtaining that the optimum value of Nt is 1010 cm−2 at both interfaces. Device optimization is achieved by obtaining a maximum Power Conversion Efficiency (PCE) of 27.22% with an open circuit voltage (Voc) of 0.63 V, a short circuit current density (Jsc) of 51.43 mA cm−2 and a fill factor (FF) of 83.06%, which makes FeSi2 a potential alternative for the development of CdTe-based solar cells due to its absorption of photons with lower energy wavelengths.