bluuebunny/crossref_metadata_2025_split huggingface dataset:
A 6 month-long real-time time scale steered to NIM-Sr1 optical lattice clock
Authors: Zhu Lin , Wang Qiang , Wang Yuzhuo , Lin Yige , Yang Dongfang , Li Ye , Yang Tao , Meng Fei , Lin Baike , Tian Haochen , Lu Bingkun , Fang Zhanjun 
Published: September 2024

Abstract
NIM-Sr1 optical lattice clock has been operated intermittently for seven consecutive months with an operation uptime around 13.8%, which serves as the reference to steer a hydrogen maser for generating a real-time time scale TS(Sr1). The peak-to-peak time difference of TS(Sr1) compared to UTC is 1.8 ns within 180 d and is less than 0.5 ns within the last month, after correcting the time error induced by a time transfer link abnormality. A dedicated automation system with hardware and software is developed to monitor the operation status of NIM-Sr1, process the measurement data, and periodically predict the hydrogen maser frequency. According to the simulation results, a composite algorithm based on both Kalman filtering (KF) and weighted least squares fitting (WLSF) is utilized for generating TS(Sr1). The KF is utilized when the unavailability of NIM-Sr1 is shorter than 1 d, and the WLSF with fitting interval

T

fit

=
30

d

is utilized in other conditions leveraging the long-term predictability of the hydrogen maser. In addition, it is demonstrated by simulation and the post-processing of earlier experimental data that, a time scale with smaller time error can be achieved by shortening the WLSF interval from 30 d to about 5 d under the condition of sufficient measurement data points for reducing the statistical error.
Metal-semiconductor-metal UVA photodetector based on TiO2 thin films synthesized via liquid phase deposition method
Authors: Baqandwan Hanadi , Rajamanickam Suvindraj , Samsuri Siti Azrah Mohamad , Halim Mohd Mahadi , Pakhuruddin Mohd Zamir 
Published: September 2024

Abstract
In this work, titanium dioxide (TiO2) thin film-based metal-semiconductor–metal (MSM) ultraviolet (UV) photodetectors (PDs) were fabricated on glass substrates via liquid phase deposition (LPD) technique at various deposition time in the range of 3–6 h. Varying deposition time significantly impacted the physical properties of the films. Increasing the deposition time revealed a mixture of clusters and hexagonal-like structures in film’s morphology. The energy band gap of the TiO2 films decreased from 3.30 to 3.09 eV upon increasing the deposition time. Photodetection characteristics were examined by exposing the MSM UV PD to 390 nm UV light with an intensity of 1.6 mW cm−2 and a bias voltage of 5 V. The fabricated PDs implied characteristics of I-V ohmic contact. The optimum photodetection characteristics were achieved for TiO2 film deposited at 6 h which exhibited 36.9 μA maximum photocurrent, 20080.3% sensitivity, 201.80 gain, 225 mA W−1 responsivity, 81.07% external quantum efficiency, 0.276 s response time, and 0.274 s recovery time. The photoelectric properties of the films were strongly affected by the increased grain size and improved crystallinity of the films due to the prolonged deposition time. The optimum film demonstrated its potential to be a promising candidate for UV PD applications.
Relationship between self-propelled velocity and Brownian motion for spherical and ellipsoid particles
Authors: Wang 汪 Jingwen 静文 , Xu 徐 Ming 明 , Nie 聂 Deming 德明 
Published: September 2024

Abstract
The Brownian motion of spherical and ellipsoidal self-propelled particles was simulated without considering the effect of inertia and using the Langevin equation and the diffusion coefficient of ellipsoidal particles derived by Perrin. The Péclet number (Pe) was introduced to measure the relative strengths of self-propelled and Brownian motions. We found that the motion state of spherical and ellipsoid self-propelled particles changed significantly under the influence of Brownian motion. For spherical particles, there were three primary states of motion: 1) when Pe < 30, the particles were still significantly affected by Brownian motion; 2) when Pe > 30, the self-propelled velocities of the particles were increasing; and 3) when Pe > 100, the particles were completely controlled by the self-propelled velocities and the Brownian motion was suppressed. In the simulation of the ellipsoidal self-propelled particles, we found that the larger the aspect ratio of the particles, the more susceptible they were to the influence of Brownian motion. In addition, the value interval of Pe depended on the aspect ratio. Finally, we found that the directional motion ability of the ellipsoidal self-propelled particles was much weaker than that of the spherical self-propelled particles.
Multiframe-integrated, in-sensor computing using persistent photoconductivity
Authors: Jiang Xiaoyong , Ye Minrui , Li Yunhai , Fu Xiao , Li Tangxin , Zhao Qixiao , Wang Jinjin , Zhang Tao , Miao Jinshui , Cheng Zengguang 
Published: September 2024

Abstract
The utilization of processing capabilities within the detector holds significant promise in addressing energy consumption and latency challenges. Especially in the context of dynamic motion recognition tasks, where substantial data transfers are necessitated by the generation of extensive information and the need for frame-by-frame analysis. Herein, we present a novel approach for dynamic motion recognition, leveraging a spatial-temporal in-sensor computing system rooted in multiframe integration by employing photodetector. Our approach introduced a retinomorphic MoS2 photodetector device for motion detection and analysis. The device enables the generation of informative final states, nonlinearly embedding both past and present frames. Subsequent multiply-accumulate (MAC) calculations are efficiently performed as the classifier. When evaluating our devices for target detection and direction classification, we achieved an impressive recognition accuracy of 93.5%. By eliminating the need for frame-by-frame analysis, our system not only achieves high precision but also facilitates energy-efficient in-sensor computing.
The effects of neuron morphology and spatial distribution on the selectivity of dorsal root ganglion stimulation
Authors: Farooqui Juhi , Nanivadekar Ameya C , Capogrosso Marco , Lempka Scott F , Fisher Lee E 
Published: September 2024

Abstract

Objective. For prosthesis users, sensory feedback that appears to come from the missing limb can improve function, confidence, and phantom limb pain. Numerous pre-clinical studies have considered stimulation via penetrating microelectrodes at the dorsal root ganglion (DRG) as a potential approach for somatosensory neuroprostheses. However, to develop clinically translatable neuroprosthetic devices, a less invasive approach, such as stimulation via epineural macroelectrodes, would be preferable. This work explores the feasibility of using such electrodes to deliver focal sensory feedback by examining the mechanisms of selective activation in response to stimulation via epineural electrodes compared with penetrating electrodes. Approach. We developed computational models of the DRG, representing the biophysical properties of the DRG and surrounding tissue to evaluate neural responses to stimulation via penetrating microelectrodes and epineural macroelectrodes. To assess the role of properties such as neuron morphology and spatial arrangement we designed three models, including one that contained only axons (axon only), one with pseudounipolar neurons arranged randomly (random), and one with pseudounipolar neurons placed according to a realistic spatial distribution (realistic). Main results. Our models demonstrate that activation in response to stimulation via epineural electrodes in a realistic model is commonly initiated in the axon initial segment adjacent to the cell body, whereas penetrating electrodes commonly elicit responses in t-junctions and axons. Moreover, we see a wider dynamic range for epineural electrodes compared with penetrating electrodes. This difference appears to be driven by the spatial organization and neuron morphology of the realistic DRG. Significance. We demonstrate that the anatomical features of the DRG make it a potentially effective target for epineural stimulation to deliver focal sensations from the limbs. Specifically, we show that epineural stimulation at the DRG can be highly selective thanks to the neuroanatomical arrangement of the DRG, making this a promising approach for future neuroprosthetic development.
Roles of ECH system in DTT plasma operations
Authors: Granucci G. , Auriemma F. , Aucone L. , Baiocchi B. , Bonanomi N. , Braghin F. , Bruschi A. , Busi D. , Casiraghi I. , di Grazia L.E. , Fanale F. , Figini L. , Garavaglia S. , Mantica P. , Mattei M. , Moro A. , Nowak S. , Platania P. , Ricci D. , Rispoli N. , Romano A. , Rubino G. , Schmuck S. , Simonetto A. 
Published: September 2024

Abstract
The Divertor Tokamak Test (DTT) facility is equipped with auxiliary heating systems in order to be able to load the divertor with a power flux relevant to study the power exhaust issue in a reactor relevant range of parameter. The powerful system is the Electron Cyclotron Heating (ECH) with an installed power of 32 MW in its largest extension. Together with the bulk heating of the DTT plasma, the ECH system will cover several tasks for the plasma operation. This paper summarizes the main characteristics and design choices of the DTT ECH system and the related physics studies, based on the reference DTT plasma, to develop and control the plasma, fulfilling the functional tasks, with the support of simulation activities. Dedicated studies have been carried out to investigate the capability of EC power to assist plasma start-up, stabilize MHD activity and support current ramp up/down. In addition, it has been studied how changes of the ECH power distribution can have an impact on the plasma profiles, affecting the fueling pellet effectiveness and MHD modes.
A comparative analysis of flow characteristics inside a closed-ended micro-shock tube using both pressure-based and density-based algorithms
Authors: Srivastava Ayushman , Kundu Abhishek , Ranjan Paul Akshoy 
Published: September 2024

Abstract
This work intends to compare the pressure-based coupled algorithm and the density-based algorithm for the two-dimensional high speed gas-particle two-phase compressible flow in the closed-ends micro-shock tube. The micro-shock tube is employed in the medical sector for the drug delivery without needle. The mass along with momentum transfer equations for compressible flow, together with the computational approach, are provided. These solvers are used to perform the transient simulation. The pressure-based algorithm offers the versatility to address flow issues using either a coupled or a segregated method. Choosing the coupled technique over the non-coupled or segregated approach has some benefits. In particular, the linked scheme outperforms segregated solution techniques and provides a reliable and effective solution for steady-state flows. The den sity-based and pressure-based segregated methods using SIMPLE-type pressure-velocity coupling is replaced by this pressure-based coupled technique. Using the coupled approach becomes essential when dealing with poor mesh quality or when using high time steps in the case of transient flows. The schlieren and vorticity contours were obtained to analyze and compared for both the solvers to determine their efficacy to capture the shock waves and fluid element rotation. This is the major gap and novelty found through the literature survey for such kind of problem. The pressure histories and Mach no. were recorded for both the solvers. The result obtained through these solvers show that though the pressure-based algorithm is capable for handling high speed compressible flow problem but when it comes about the CPU time as well as the accuracy of the result, the density-based solver is more reliable for this problem.
Drag lift characteristics of a NACA 4412 airfoil with angle of attack
Authors: Ghose Prakash , Kumar Sahoo Tarak , Kumar Patel Jitendra , Kumar Nayak Swarup , Kumar Rana Basanta 
Published: September 2024

Abstract
Unsymmetrical airfoils are used to get a better lift-to-drag ratio. In this work, the overall performance of a NACA4412 unsymmetrical airfoil has been investigated through CFD simulations. The angle of attack is varied from 0° to 20° at the interval of 2°. The airflow velocity is kept constant at 30 m/s. From the investigation, it is observed that the optimum CL to CD ratio is obtained at an angle of attack of 5°. Beyond 5° AA, the CD rises rapidly. With an increase in AA, a backflow is observed near the trailing edge on the top half of the airfoil. The backflow becomes stronger with the increase in AA. The stagnation point also moves down towards the bottom surface from the tip of the airfoil with the increase in AA.
Simulation assessment of the absorber tube of a solar parabolic trough collector using two types of spiral indentations
Authors: Sarangi Asish , Sahoo Sudhansu S. , Mallik Ramesh K. 
Published: September 2024

Abstract
Effective solar energy usage and solar energy gathering have grown in prominence due to the dearth of fossil fuels in recent years. In the current research, the absorber tube of a parabolic trough solar collector having two types of indentations has been considered and numerically simulated. For these studies, a steady heat flux has been considered on the tube. Fluid flow in the tube is subjected to turbulence and for which, the k-RNG turbulence model is utilized. It is revealed that the Nusselt number for absorber tubes with trapezoidal indentations is found to be 72.11, indicating superior thermal efficiency compared to 65.59 for rectangular indentations. However, trapezoidal indentations also result in a higher friction factor leading to a pressure drop of 247.21 Pa than rectangular indentations having a pressure drop of 159.81 Pa. The selection of either rectangular or trapezoidal indentations is contingent upon the particular demands of the application, including factors such as effectiveness, cost, and operational limitations. In situations when it is crucial to minimize energy consumption for fluid flow, the use of a rectangular indentation may be more advantageous. However, if other variables like as heat transfer efficiency take precedence and the extra energy expenditure for pumping can be rationalized, then the trapezoidal indentation may be the preferable option.
Heat transfer analysis of TiO2-H2O based nanofluid flow across a porous stretching sheet with heat source/sink using Response Surface Methodology
Authors: Reshmi V P , Nagaraja K V , Shankara  
Published: September 2024

Abstract
Efforts are focused on optimizing thermal energy control and utilization within the system. The analysis is done on heat transmission characteristics of a TiO2.H2O nanofluid flowing over a stretching sheet with an integrated heat source/sink. Sensitivity analysis is performed using Response Surface Methodology (RSM) to understand heat transfer behaviour effectively. Governing equations are transformed into ordinary differential equations using suitable similarity variables. Mathematical formulation for steady two-dimensional flow of nanofluid in a porous medium along with a stretching sheet is established, and numerical outcomes are optimized using RSM. Influence of porous medium (A), volume fraction (Φ), and heat source/sink (Hs) on Nusselt number (Nu) and skin friction factor (Cf) is analyzed through normal, response surface, and contour plots and it is found that for increasing Hs decreases Nu for higher Φ values.
A Comparison of Classical Nucleation Theory and Thermal Phase Change Based Condensation Models
Authors: Das Sahu Kapil , Sunder Yadav Shyam , Sankar Dasgupta Mani 
Published: September 2024

Abstract
In this work, we perform numerical simulations of the condensation process of CO2 inside a converging-diverging nozzle. We use Ansys Fluent for the simulation work. The real gas properties of CO2 are generated in tabular form (including metastable states) using NIST Refprop. We compare the distribution of physical quantities during the high-speed, compressible flow of CO2 inside a nozzle under the Classical Nucleation Theory (CNT) and the Thermal Phase Change (TPC) models. The CNT model is known to be accurate but computationally expensive while the TPC model is computationally cheaper. We observe that the TPC model predicts a knee in the pressure distribution near the throat of the nozzle while CNT predicts a continuous decrease in the pressure. The two solvers predict slightly different temperature, supercooling and liquid mass fraction values in the diverging part of the nozzle. The compressible, phase change simulations under high speed conditions can be performed quickly with the TPC solver. Overall, the TPC based solver appears to be a reliable alternative to the CNT based model.
Experimental investigation on Counter Flow Double-Pass Solar Air heater with absorber attached with perforated C-shaped Fins.
Authors: Krishna Dutta Ajoy , Kanta Rabha Deva 
Published: September 2024

Abstract
A solar air heater with double-pass and counter flow featuring a perforated C-shaped finned absorber, considering mass flows of 0.041, 0.045 and 0.049 kg/s was investigated experimentally in an outdoor environment. The results of the experiments indicate that solar irradiance, ambient temperature, and the mass flow of air have a noteworthy impact on the efficiency, air temperature rise, and thermal effectiveness of the solar air heater. A noticeable trend indicates a reduction in the efficiency of the heater as the mass flow of air decreases. The mean thermal efficiencies at air mass flows of 0.041, 0.043 and 0.049 kg/s were found to be 77.46, 79.81 and 82.79%, respectively. The temperature rise per unit solar irradiance for the air mass flows of 0.041, 0.043 and 0.049 kg/s were 0.027, 0.026, and 0.025 °C/W-m2, respectively. The thermal effectiveness of the heater was 73.34 72.28 and 70.31% at 0.043, 0.045, 0.049 kg/s air mass flows, respectively. It is noteworthy that the thermal effectiveness declines as the mass flow rates of air decreases.
Quantitative and Comparative evaluation of Titanium Dioxide and Zirconium Dioxide Dental Implants under the effect of average masticatory load: A Computational Approach
Authors: Rani Panda Smita , Chandra Routra Bharat , Chakrabarty Shanta 
Published: September 2024

Abstract
This study investigates the impact of average masticatory loads on dental implants, focusing on titanium dioxide and zirconium dioxide materials due to their corrosion resistance and plaque prevention properties. Utilizing the Finite Element Method, the stresses and deflections in these implant components under an average masticatory load of 100N were evaluated. Locations experiencing the highest loads, and time-dependent stresses and deflections are quantitatively measured to analyze the effect of average masticatory load. The findings provide quantitative insights into how these materials withstand masticatory forces, offering valuable information for dental implant design and durability.
Advancements in Tool Wear Monitoring in Turning Operations: Digital Image Processing and AI Techniques
Authors: Agrawal Kushagra , Panda Amlana , Kumar Sahoo Ashok 
Published: September 2024

Abstract
Tool wear monitoring in machining operations is vital for maintaining product quality and minimizing downtime. Traditional methods, like optical microscopy, are often time consuming and offline. However, advancements in digital image processing, particularly machine vision, have made online tool wear monitoring more feasible. This systematic literature review investigates the application of artificial intelligence (AI) techniques in tool wear monitoring over the past two decades. The review reveals a growing interest in AI-based approaches, particularly Artificial Neural Networks (ANN) and Convolutional Neural Networks (CNN), for stable turning operations and online prediction. Key trends in input selection, preprocessing techniques, and output considerations across various AI models are identified, providing valuable insights into the evolving landscape of tool wear monitoring methodologies. Looking ahead, the future of tool wear monitoring appears promising, with continued advancements in AI technologies. Challenges remain, including the variable evolution of tool degradation and underutilization of CNC data. Addressing these challenges will require interdisciplinary collaboration and innovative solutions. In conclusion, AI-driven tool wear monitoring represents a promising approach to enhance productivity and quality in the metal cutting industry.
Different trajectory patterns of ocean surface drifters modulated by near-inertial oscillations
Authors: Zheng Yuhang , Wu Wei , Wang Minyang , Zhang Yuhong , Du Yan 
Published: September 2024

Abstract
Near-inertial oscillations (NIOs) are widely observed dynamic motions in the global ocean, with a frequency related to earth’s rotation. Using a particle trajectory model, we found the combined influence of mesoscale eddies and NIOs could produce distinctive flower-like trajectories, which are a special case of near-inertial trajectories and were observed by surface drifters released within an anticyclone eddy in the South China Sea in 2021. The energy budget indicates that wind and geostrophic eddy currents are crucial in generating near-inertial energy during the flower-like trajectories. Furthermore, the particle trajectory model revealed variations in periods and widths of the near-inertial trajectory with latitudes. The width of near-inertial trajectories can exceed 8 km in the near-equatorial region and reach 3–6 km in the mid-latitude region (20°–50°). The ratios of near-inertial velocity to background velocity, defined as near-inertial trajectory shape index (NITSIs), lead to arc-shaped (0.5 < NITSI < 1.0), overlapping semi-circular (NITSI > 1.0), and near-circular trajectories (NITSI ≫ 1.0). Globally, approximately 1/3 of the drifters’ lifespan featured clear near-inertial trajectories, with a significant presence in most middle latitudes and the largest NITSI in the north Pacific westerly. These findings highlight the importance of NIOs and suggest their substantial impact on local surface matter distribution, trajectory prediction, and marine rescue operations.
Forest structure explains spatial heterogeneity of decadal carbon dynamics in a cool-temperate forest
Authors: Takagi Kentaro , Hirayama Kojiiro , Hayashi Masato , Makoto Kobayashi , Okada Keiji , Oguma Hiroyuki , Saigusa Nobuko 
Published: September 2024

Abstract
Accurate evaluation of forest biomass distribution and its long-term change over wide areas is required for effective forest carbon management and prediction of landscape-scale forest dynamics. We evaluated a landscape-scale (225 km2) decadal forest carbon budget at a 1 ha spatial resolution in a cool-temperate forest, by repeating airborne laser observations 10 years apart and partitioning net forest biomass change (FBC) into growth and mortality. Using >10 000 samples, we revealed that naturally regenerated forests have large spatial heterogeneity in net biomass change, and 3/4 of the photosynthetically acquired carbon stock moved to necromass even without anthropogenic disturbances. Actual carbon residence time as living tree biomass was estimated by dividing biomass by growth or mortality rates. The residence time was 107 and 106 years, respectively with large spatial variation among stands (48 and 42 years, respectively, as the difference between 25 and 75 percentile), although studied forest stands have small variation in the forest functional type in a landscape-scale. The best predictors of subsequent decadal biomass changes were two forest structural factors, mean canopy height and canopy height variation in addition to one environmental factor, elevation. Considering the long lifetime of trees, these structural factors may be an indicator of forest soundness rather than a cause of forest growth or mortality. However, in any cases, these structural factors can be powerful predictors of subsequent FBC.