bluuebunny/crossref_metadata_2025_split huggingface dataset:
Harmonic voltage measurement based on capacitive equipment dielectric equivalent model and responding current
Authors: Du Lin , Feng Hui , Li Xin , Shao Xianjun , Yang Zhi 
Published: July 2024

Abstract
With the increasing proportion of new energy and the power electronic equipment in the power grid, accurate measurement of harmonic voltage has become increasingly important for power quality monitoring. In order to solve the problem of high-precision measurement of harmonic voltage in the power grid, this manuscript proposes a high-precision harmonic voltage measurement method based on the dielectric equivalent model (DEM) of capacitive equipment and its responding current. Based on DEM, a voltage-current transfer function of the capacitive equipment is established, and harmonic voltage is reconstructed with the responding current. Considering the dielectric relaxation characteristics of capacitive equipment other than a pure capacitor model, this manuscript analyzes the fitting performance of different equivalent capacitance models and improves the traditional pure capacitance model to a more suitable DEM for harmonic voltage reconstruction. The DEM parameters of capacitive equipment are obtained through the frequency domain spectroscopy and intelligent parameter identification algorithms, which improved the measurement accuracy of harmonic voltage and reduced computational complexity. The harmonic voltage testing platform is established to test the simulated high-voltage harmonics and the harmonic voltage of the actual grid voltage. The results show that the proposed harmonic voltage measurement method can meet the high-precision reconstruction of harmonic voltage in the frequency range of 50–2500 Hz, and the system testing error with sensors is less than 2%. The testing accuracy is higher than traditional voltage transformers and testing systems based on pure capacitance models.
A novel simulation-assisted transfer method for bearing unknown fault diagnosis
Authors: Huang Fengfei , Li Xianxin , Zhang Kai , Zheng Qing , Ma Jiahao , Ding Guofu 
Published: July 2024

Abstract
Supervised data-driven bearing fault diagnosis methods rely on completed datasets of faults, which can be challenging for signals collected in real engineering. Recognizing unknown faults using a data-driven approach is particularly difficult, as purposefully modeling these faults is complex. To address this challenge, this study proposes a new simulation-assisted transfer bearing unknown fault diagnosis method for realizing unknown compound fault diagnosis of rotating machinery. Firstly, finite element method is used to obtain the compound fault data that does not exist in the historical data, and wavelet packet transform is performed on the simulated and measured signals to enhance the detailed features of the signals. Then, a deep convolutional feature fusion network based on hybrid multi-wavelet spatial attention is constructed to fuse the time-frequency information processed by different wavelet bases. Finally, by integrating the concepts of intra-class splitting and transfer learning, the model is fine-tuned using simulation data to recognize unknown compound faults of rolling bearings. The method validates the simulated signals’ feasibility and the unknown faults’ diagnostic validity under the publicly available rolling bearings dataset. Compared to the comparison methods, the method’s accuracy increased by 2.86%, 2.61%, 5.41%, 4.77%, and 7.07%, respectively.
Three-dimensional contour detection method based on fusion of machine vision and laser radar
Authors: Jun Wu , Shuo Huang , Shaobo Yuan , Long Jin , Runxia Guo , Jiusheng Chen 
Published: July 2024

Abstract
In the current methods of point cloud processing, there are still several limitations, particularly in achieving high precision and accuracy for large objects in complex environments. Existing techniques often struggle with incomplete or noisy data, leading to inaccurate contour extraction. In view of the challenges associated with the sparse and discrete nature of point clouds in complex environments, which lead to poor accuracy and stability in object contour extraction, this paper proposes a novel method for accurately extracting the contours of three-dimensional target point clouds. The method integrates high-resolution images with sparse point cloud information to address these issues. Firstly, the local characteristics of the point cloud are calculated, allowing for the selection of a contour point cloud. Next, depth information from two-dimensional images is obtained through a fuzzy mapping relationship. Finally, constraint conditions are established to derive a more accurate predicted value of the contour point cloud. Experiments demonstrate that the proposed method effectively improves the precision and accuracy of contour extraction for large objects, reducing measurement deviation by approximately 64.9% compared to using the original point cloud alone. Additionally, the method shows a more accurate completion effect on parts of the contour that are missing, underscoring its robustness and effectiveness in challenging scenarios.
Stationary prospective cardiac gated computed tomography—dynamic study in phantoms and in vivo
Authors: Billingsley Alex , Inscoe Christina , Attia Mohamed Fathy , Lu Jianping , Zhou Otto , Lee Yueh Z 
Published: July 2024

Abstract

Objective. This study explores the feasibility of a stationary gantry cardiac gated computed tomography (CT) with carbon nanotube (CNT) linear x-ray source arrays. Approach. We developed a stationary gantry CT system utilizing multipixel CNT x-ray sources. Given the advantages of straightforward x-ray pulse control with these sources, we investigated the potential for gated prospective imaging. We implemented prospective respiratory and cardiac gating control and evaluated the system through dynamic phantom imaging studies followed by imaging of a porcine model. Main Results. The findings revealed minimal anatomical motion artifacts in the heart and lungs, confirming successful physiologic gated acquisition in stationary gantry cardiac CT. This indicates the potential of this imaging approach for reducing artifacts and improving image quality. Significance. This study demonstrates the feasibility of prospective physiological gating with CNT x-ray sources in a stationary gantry setup for cardiac imaging. This approach could potentially alleviate the need for beta blocker administration during cardiac CT scans, thereby increasing the flexibility of the imaging system and enabling the imaging of a wider variety of patient cardiac conditions.
The advent of quantum computer music: mapping the field
Authors: Miranda Eduardo Reck 
Published: July 2024

Abstract
Quantum computing technology is developing at a fast pace. The impact of quantum computing on the music industry is inevitable. This paper maps the emerging field of quantum computer music. Quantum computer music investigates, and develops applications and methods to process music using quantum computing technology. The paper begins by contextualising the field. Then, it discusses significant examples of various approaches developed to date to leverage quantum computing to learn, process and generate music. The methods discussed range from rendering music using data from physical quantum mechanical systems and quantum mechanical simulations to computational quantum algorithms to generate music, including quantum AI. The ambition to develop techniques to encode audio quantumly for making sound synthesisers and audio signal processing systems is also discussed.
Liquid crystals from curved colloidal rods: waves, twists and more
Authors: Fernández-Rico Carla , Dullens Roel P A 
Published: July 2024

Abstract
The curvature of elongated microscopic building blocks plays a crucial role on their self-assembly into orientationally ordered phases. While rod-like molecules form a handful of liquid crystal (LC) phases, curved or banana-shaped molecules show more than fifty phases, with fascinating physical properties, such as chirality or polarity. Despite the fundamental and technological importance of these so-called ‘banana-shaped liquid crystals’, little is known about their microscopic details at the single-molecule level. Curved colloidal liquid crystals—liquid crystals formed by curved colloidal rods—are excellent model systems to optically resolve the structure and dynamics of curved building blocks within these condensed phases. Recent advances in the synthesis of curved rod-like particles have unlocked the potential for studying—at the single-particle level—the intimate relationship between shape and phase symmetry, and even confirmed the stability of elusive LC phases. Further developments in this nascent field promise exciting findings, such as the first observation of the colloidal twist-bend nematic phase or the fabrication of functional materials with curvature-dependent properties. In this Report on Progress, we will highlight recent advances in the synthesis and assembly of curved colloidal liquid crystals and discuss the upcoming challenges and opportunities of this field.
A new hybrid auxetic structure capable of uniform deformation exhibits excellent energy absorption
Authors: Deng Yunfei , Jin Yaoxiang , Li Hailin , Wang Xuan 
Published: July 2024

Abstract
As a kind of mechanical metamaterial, auxetic honeycomb with negative Poisson’s ratio has received extensive attention in recent years. In order to further improve the stable deformation and energy absorption of the auxetic structure, we combined the asymmetrical re-entrant honeycomb with the triangular honeycombs to propose a new two-dimensional (2D) auxetic structure named asymmetrical re-entrant triangular honeycomb (ART). By setting up comparative experiments, quasi-static compression tests for ART and two existing honeycomb structures (re-entrant star-shaped honeycomb and re-entrant hexagonal honeycomb) along in-plane directions were conducted. A series of ART configurations with different parameters were established, and finite element simulation was used to explore the effects of parameters on the mechanical properties of ART. The unilateral horizontal maximum strain is cited to assess the deformation stability of the structures. The experimental and simulation results show that the deformation of ART is uniform in both in-plane directions. In the compressive strain range that we studied, the specific energy absorption of ART in both directions can be up to 291% and 271% higher than that of the existing structures, respectively, providing excellent load-bearing and energy absorption. In addition, the mechanical properties of ART can be adjusted by changing the geometrical parameters to provide ideas for structural design.
Theoretical analysis and experimental research of piezoelectric-electromagnetic hybrid vibration energy harvester
Authors: Zhang Xuhui , Cheng Yujun , Yang Wenjuan , Pan Jianan , Chen Xiaoyu , Xu Hengtao , Tian Hao , Zhang Jialin 
Published: July 2024

Abstract
To address the concerns of single-mode energy harvesters’ low output power and inefficient energy utilization, this paper proposes a novel piezoelectric–electromagnetic hybrid vibration energy harvester to enhance energy harvesting performance. In order to obtain the dynamic properties and evaluate the efficiency of the proposed hybrid energy harvester, an electromechanical coupling dynamic model was established, and the corresponding voltage, current, and output power of the hybrid energy harvester were calculated. The dynamical responses of the hybrid energy harvester obtained in the numerical simulations were discussed to reveal the influence of key parameters such as the excitation amplitude, load resistance, and initial magnetic distance. Then the validation experiments were conducted to verify the numerical simulation results. The results indicated that the excitation amplitude had a significant effect on the output voltage and output power. Meanwhile, the optimum load resistance and magnetic distance could boost the power generating performance of the hybrid energy harvester. The total output power of the hybrid energy harvesters can reach to 38.2 mW, which is 164.6% and 60.5% higher than those of the corresponding piezoelectric and electromagnetic energy harvesters, respectively. The results of this paper provide a new method for enhancing the performance of vibration energy harvester by means of hybrid energy conversion mechanism from an experimental and theoretical point of view.
Engineering the active layer of lead-free perovskite (CH3NH3SnI3) solar cells using numerical simulation
Authors: Yadav Sarita , Gupta Saral K , Negi C M S 
Published: July 2024

Abstract
We conduct a thorough numerical simulation to examine the impact of the thickness, defect density, and doping density of the active layer on the photovoltaic performance of the lead-free CH3NH3SnI3 perovskite solar cell (PSC). We observe that increasing the thickness of the active layer initially from 100 nm to 400 nm improved the power conversion efficiency (PCE) from 10.4% to 11.6%. However, further increasing the thickness to 800 nm resulted in a slight decline in PCE to 11.1%. This unexpected trend can be attributed to the high carrier mobility of charges in the CH3NH3SnI3 perovskite, which enables fast extraction of charge carriers, offsetting losses due to charge recombination. Increasing active layer trap density substantially declines the PCE from 11.5% at 1014 cm−3 to 7.5% at 1018 cm−3, as a result of the noticeable drop in open-circuit voltage (VOC) and fill factor (FF) with a growing defect density due to the enhancement in trap-assisted recombination. This is backed by a striking reduction in the shunt resistance upon increasing the defect density. Raising the active layer doping firstly enhances the PCE, reaching a peak value of 12.5% at the active layer doping density of 1017 cm−3, after which the PCE decreases as the doping density continues to increase. We explain these observations by energy level diagrams deduced at various doping levels.
Microstructural and electrochemical properties of Co3O4 porous nanospheres
Authors: Afrooze Anjum , Shaik Dadamiah PMD 
Published: July 2024

Abstract
In this study, Co3O4 porous nanospheres were synthesized at 200 °C using a solution combustion method and subsequently annealed at 600 °C. The microstructural and electrochemical properties of these nanostructured Co3O4 samples are thoroughly investigated. X-ray diffraction (XRD) analysis of all samples revealed prominent peaks corresponding to the (220), (311), (222), (400), (422), (511), and (440) planes, which are indicative of the Co3O4 cubic structure with the space group Fd 3̄ m (227). Raman spectroscopy confirmed the presence of Co–O bonds and provided insights into the Functional groups of the samples. Scanning Electron Microscopy (SEM) was employed to examine the materials’ dimensions and surface architecture, revealing detailed features of the porous nanospheres. X-ray Photoelectron Spectroscopy (XPS) analysis verified the presence of Co2+ and Co3+ ions alongside O2− in a spinel configuration, confirming the chemical state of the constituents. Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) analyses showed characteristic of porous material. The electrochemical performance of the Co3O4 porous nanospheres was evaluated in a 1M KOH aqueous electrolyte. The as-prepared samples exhibited a maximum capacitance of 309 F g−1 at a current density of 1 A g−1, along with enhanced electrochemical stability, maintaining a significant proportion of their initial capacitance even after 2000 cycles.
Late time dynamics in SUSY saddle-dominated scrambling through higher-point OTOC
Authors: Das Rathindra Nath , Dutta Sourav , Maji Archana 
Published: July 2024

Abstract
In this article, we propose higher-point out-of-time-order correlators (OTOCs) as a tool to differentiate chaotic from saddle-dominated dynamics in late times. As a model, we study the scrambling dynamics in supersymmetric quantum mechanical systems. Using the eigenstate representation, we define the 2N-point OTOC using two formalisms, namely the ’Tensor Product formalism’ and the ’Partner Hamiltonian formalism’. We analytically find that the 2N-point OTOC for the supersymmetric 1D harmonic oscillator is in exact agreement with that of the 1D bosonic harmonic oscillator system. We show that the higher-point OTOC is a more sensitive measure of scrambling than the usual 4-point OTOC. To demonstrate this, we analyze a supersymmetric sextic 1D oscillator, for which the bosonic partner system has an unstable saddle in the phase space, while the saddle is absent in the fermionic counterpart. For such a system, we show that the saddle-dominated scrambling, higher anharmonic potential effects, and the supersymmetric OTOC exhibit similar dynamics due to supersymmetry constraints. Finally, we illustrate that the late-time dynamics of the higher-point OTOC become oscillatory after the peak for saddle-dominated scrambling and anharmonic oscillator systems. We propose the higher-point OTOC as a probe of late-time dynamics in non-chaotic systems that exhibit fast early-time scrambling.
Refractive index sensor based on an annular cavity and an equilateral triangular cavity for temperature detection
Authors: Yan Shubin , Wang Jin , Su Yiru , Liu Feng , Chang ShuWen , Cao Yuhao , Cui Yang , Liu Jilai , Zhang Yi , Ren Yifeng 
Published: July 2024

Abstract
The present study proposes a novel refractive index sensor utilizing asymmetric linear scattering frequency phenomena, which is formed by coupling a metal insulator metal (MIM) waveguide structure with an equilateral triangular ring cavity structure(ETRC). The transmission characteristics of the sensor structure were investigated using finite element method (FEM),with a focus on the effect of structure-related variables on sensing characteristics. Due to its advantages of small size, fast reaction speed, and flexibility, the designed sensor can achieve sensitivity and light efficiency values of 2880 nm RIU−1 and 50.53. In addition to this, the sensor structure can also be applied in the field of temperature detection with a sensitivity of up to 1.46 nm °C−1.
Dynamics of memristive Liu system and its DSP implementation
Authors: Tayyab Muhammad , Sun Kehui , Yao Zhao , Wang Huihai 
Published: July 2024

Abstract
In this paper, a novel four-dimensional memristive system is investigated to generate abundant dynamical behaviors. By combining the Liu chaotic system with an ideal memristor, an enhanced chaotic system is proposed. Dynamical analysis indicates that the new system sustains stable chaotic states and exhibits complex behaviors, with the help of the Lyapunov exponents, bifurcation diagrams, Poincaré section, parametric offset boosting, and SE complexity. The coexistence of attractors is investigated by the variation of parameters. The chaotic performance is enhanced in the proposed system, broadens the range of parameters for chaotical oscillations, and transforms periodic and quasiperiodic states into chaos. The practical applicability and feasibility of the system are validated via NIST testing and DSP implementation. The system exhibits resilient dynamical characteristics that make it highly suitable for deployment in various domains, including secure communication and signal detection.
An innovative design and metrological testing to evaluate the performance of UV phototherapy devices
Authors: Faramawy Samaa M 
Published: July 2024

Abstract
Narrowband UVB is the main type of light used to treat various dermatological conditions by administering appropriate doses. In this study, a new design was developed for an open-plan phototherapy device and assessed whether this could improve uniformity and deliver a higher dose, thus reducing treatment times. On the other hand, the uniformity and irradiation dose of a current model of (UV) phototherapy device were investigated. A simulation software was used to present the comparison of the simulated irradiation measurements and uniformity estimation for both the present device and the proposed device. In comparison to a present model of UV therapy device measurements, the results showed that the suggested (UV) phototherapy design device increased the irradiation dose value by 10%, improved the uniformity by 9.3%, and consequently reducing the exposure time by 13%. On the other hand, for both the current (UV) phototherapy equipment and the suggested design device, the irradiation loss value resulting from any UV lamp inefficiency was also calculated. The current model device’s loss value percentage was 15%, however, the loss value of the suggested design for the UV phototherapy device was between 3 and 4%. Based on the results discussed throughout the paper, the findings indicate that the suggested design is promising for UV phototherapy applications.
Magnetar-powered neutrinos and magnetic moment signatures at IceCube
Authors: Brdar Vedran , Cheng Ting , Kuan Hao-Jui , Li Ying-Ying 
Published: July 2024

Abstract
The IceCube collaboration pioneered the detection of 𝒪(PeV) neutrino events and the identification of astrophysical sources of high-energy neutrinos.
In this study, we explore scenarios in which high-energy neutrinos are produced in the vicinity of astrophysical objects with strong magnetic field, such as magnetars. While propagating through such magnetic field, neutrinos experience spin precession induced by their magnetic moments, and this impacts their helicity and flavor composition at Earth.
Considering both flavor composition of high-energy neutrinos and Glashow resonance events we find that detectable signatures may arise at neutrino telescopes, such as IceCube, for presently unconstrained neutrino magnetic moments in the range between 𝒪(10-15) μB
and 𝒪(10-12) μB
.
Casson hybrid nanofluid flow over a Riga plate for drug delivery applications with double diffusion
Authors: Alnahdi Abeer S. , Gul Taza 
Published: July 2024

Abstract
Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity. Heat exchangers, cooling systems and other thermal management systems are ideal for use with Casson fluids. Precise control of the flow and release of medication is necessary when using Casson fluids in drug delivery systems because of their unique rheological properties. Nanotechnology involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted delivery. In this study, to create a hybrid nanofluid, both single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are dispersed in a Casson fluid with Fourier’s and Fick’s laws assumptions. The Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by the carbon nanotubes. Our objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga plate. The Darcy–Forchheimer model is also used to account for the impact of the porous medium near the stretching plate. Both linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the nanofluid. In addition, the homotopy analysis method is utilized to address the model problem. The outcomes are discussed and deliberated based on drug delivery applications. These findings shed valuable light on the flow characteristics of a Casson hybrid nanofluid comprising SWCNTs and MWCNTs. It is observed that the incorporation of carbon nanotubes makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties.