bluuebunny/crossref_metadata_2025 huggingface dataset:
Cavitating flow morphology determination in cavitation-on-a-chip devices based on local real-time pressure measurements
Authors: Toyran Erçil , Talabazar Farzad Rokhsar , Tzanakis Iakovos , Ghorbani Morteza , Koşar Ali
Published: February 2025

This study presents a practical approach for the characterization and control of hydrodynamic cavitation (HC) behavior in microfluidic devices by utilizing real-time static pressure measurements. Two geometrically identical micro-orifice devices were specifically designed for this purpose. Pressure measurement locations were strategically positioned along the embedded microchannel in both devices. These locations were determined as a function of the hydraulic diameter of the microchannel. Pressure measurements were simultaneously made with high-speed imaging. Particular attention was directed to the prediction and monitoring of cavitation inception, cavitating flow patterns, and cavitation development. Thus, the dynamic and complex nature of hydrodynamic cavitation in microdomains could be captured by local pressure variations along the microchannel walls. According to the results, cavitation inception and subsequent formation of twin sheet cavities could be detected by changes in local pressure values. Moreover, the analysis of local pressure variations could be employed to predict the length of sheet cavities. The findings of this study offer valuable guidelines for designing microfluidic systems involving hydrodynamic cavitation. Moreover, this study proves the potential of local wall pressure measurements as a stand-alone practical approach, which will reduce reliance on high-speed visualization. It could thus enhance the affordability and accessibility of HC-on-a-chip platforms for emerging applications, including biomedical engineering, wastewater treatment, and 2D material exfoliation.
Polymer flooding characteristics in modified Hele–Shaw cells
Authors: Firoozi AtaOllah , Ahmadpour Ali , Hajmohammadi Mohammad Reza
Published: February 2025

In this study, numerical simulations are employed to investigate the displacement flow of oil by viscoelastic polymer solutions inside modified Hele–Shaw cells (HSCs). The flooding characteristics within converging and diverging geometrical configurations and various flow injection rates are explored by utilizing the White–Metzner model to capture the viscoelastic behavior of hydrolyzed polyacrylamide solutions at different concentrations. The simulations are conducted in OpenFOAM using the volume of fluid method to model the multiphase interface. Results demonstrate that higher elasticity numbers (El) and lower modified capillary numbers (Ca′) enhance the oil recovery to over 75% in terms of swept volume due to improved flow stability and reduced finger branching. Additionally, the diverging HSCs positively influence the flow patterns and facilitate an extra increase in sweeping efficiency (SE) by more than 12% via favorably alleviating the stability threshold in terms of Ca′–El relationship. In contrast, the opposite holds for the converging channel, decreasing SE by 16% and narrowing down the stability region. The findings indicate that adjusting polymer concentration and cell configuration can mitigate the adverse effects of finger instability, thereby improving the overall success of oil displacement processes. Moreover, a supervised machine learning study was carried out to predict the sweep efficiency based on the flow dimensionless numbers, where the multi-layered artificial neural network was exhibited as a high-accuracy model with an R2 value of 94.46%.
Leading-edge contamination and its effects over a controlled-diffusion compressor blade for varying levels of freestream turbulence
Authors: Katiyar S. , Sarkar S.
Published: February 2025

A tiny separation bubble appears at the leading-edge of a controlled-diffusion compressor stator blade at an off-designed inflow angle of 38.3°, when a wall-resolved large-eddy simulation (LES) is employed to assess the flow field at a Reynolds number (Re) of 2.1×105. The objective of the study is to examine how this leading-edge bubble influences the transition and spatial evolution of the boundary layer on the suction surface before the mid-chord for varying levels of inlet freestream turbulence (FST). When compared with the experiment, LES resolves the flow field with an appreciable accuracy, although some discrepancies exist in the surface pressure distribution. The boundary layer is pre-transitional at the leading-edge followed by a decay in fluctuations up to 40% of the chord (C), attributing to the local flow acceleration at the FST level of 1.5%. Additionally, the boundary layer appears laminar after recovering from the leading-edge contaminations near the mid-chord but separates again because of the adverse pressure gradient with augmentation of turbulence leading to breakdown around 0.70 C. When the FST level is increased to 7.6%, an earlier reattachment occurs, shortening the leading-edge bubble length. In this case, the longitudinal streaks continuously amplify with significant three-dimensional motions near the mid-chord, and the bubble eventually disappears in the second half of the blade. In brief, the LES effectively resolves the contaminations of the boundary layer due to the appearance of the leading-edge separation with increasing levels of background disturbances.
The condensation process of supercritical water gasification products in a bicubic supersonic nozzle
Authors: Wu Hongtu , Wang Weizuo , Jin Hui
Published: February 2025

The development of energy-efficient and clean supercritical water gasification product (SCWGP) separation technology has become one of the bottlenecks in advancing supercritical water gasification technology. This study suggests utilizing a supersonic nozzle to condense and separate H2 and CO2 from SCWGP. The flow and condensation model are established for a bicubic parametric supersonic nozzle, and the effects of various operating conditions on the condensation separation of SCWGP are analyzed. The liquid phase mass fraction at the nozzle outlet is significantly influenced by the inlet pressure and temperature. The approximate relationship between inlet pressure variations and liquid phase mass fraction is 0.065 per MPa, while the relationship between inlet temperature variations and liquid phase mass fraction is approximately –0.013 per K. The latent heat released during the condensation process has a significant impact on the temperature distribution within the nozzle. Inlet parameters have a notable effect on the peak values and positions of nucleation and droplet growth rates. The condensed liquid CO2 is primarily concentrated near the center of the nozzle outlet. The efficiency of the condensation separation is strongly influenced by the molar fraction of CO2 in the gas mixture, while the small amount of N2 mixed in has little effect on the condensation separation performance.
Hemodynamic analysis on the umbilical cord with different coiling and nuchal cord conditions: A computational model-based study
Authors: Wang Tianqi , Tao Keming , Wang Weiping , Ge Xinyang , Pei Qiuyan
Published: February 2025

The umbilical cord is a vital pathway for the fetus, which can bring oxygen/nutrition and take away waste products to maintain normal growth. Clinical studies found that abnormal coiling and nuchal cord conditions of the umbilical cord may be associated with fetal growth restriction. Although the hemodynamic environment due to the abnormal morphology is suspected to account for the abnormal growth, the specific influence of the abnormal coiling and nuchal cord conditions on the hemodynamics remains not fully understood. In this context, this study aims to investigate the hemodynamic effects of the variation of umbilical coiling index (UCI) and nuchal cord conditions in order to better address the issue. For this purpose, the computational model of a normal umbilical cord was constructed based on the ultrasound-measured geometrical parameters and blood flow velocity. On this basis, a series of computational models with lower/higher UCI and with/without nuchal cord were then constructed, which were used in the hemodynamic analysis and comparison. Results showed that (1) both abnormal UCI (lower and higher) and nuchal cord conditions significantly altered the hemodynamic environment; (2) the variations of UCI resulted in inverse tendencies between oscillatory shear index (OSI) and relative residence time (RRT); and (3) nuchal cord had minor impact on most hemodynamic variables, such as wall shear stress and RRT, but increased the area of higher OSI. These findings clarified the influence of different coiling and nuchal cord conditions on the hemodynamic environment of the umbilical cord, which would provide more insights into fetal growth restriction.
Forced motion modes of a patch of flexible rods in open channel flows
Authors: Jin Caiping , Zhang Jingxin
Published: February 2025

Flexible vegetation is common in riverine and coastal ecosystems. The patch of flexible vegetation is influenced by various factors, resulting in a series of characteristic modes of motion. This study aims to investigate the influence of the Cauchy number (Ca, the ratio of the hydrodynamic drag force to the bending rigidity, i.e., the inverse of the dimensionless bending rigidity) and the solid volume fraction (which reflects the distribution density of a patch of flexible rods) on the motion modes. Additionally, the induction mechanism of fluid and flexible vegetation interaction on motion modes is investigated. A semi-resolved coupling numerical model was employed to simulate the fluid and structure interaction. The results show that the Cauchy number and solid volume fraction influence the motion modes to different extents. Notably, the effect of Ca was significant within the designed range of the two parameters. The wavelength of the monami mode generally shows little variation compared to that observed in the Kelvin–Helmholtz (K-H) vortex, which results from the mixing layer flow instability. The physical mechanism that the motion mode of a patch of flexible rods is induced by the interaction between water flow and flexible rods is further validated and cognized. When the K-H vortex frequency, the natural frequency of the patch in water, and the motion frequency of the patch are close, the patch exhibits motion in the monami mode. Otherwise, the patch will exhibit motion in erect, swaying, and prone mode.
Shift of nanodroplet and nanocluster size distributions induced by dopant pick-up statistics
Authors: Riddle Marie , Pena Dominguez Angel I. , Kamerin Benjamin S. , Kresin Vitaly V.
Published: February 2025

In pick-up experiments using nanodroplet and nanocluster beams, the size distribution of hosts carrying a specified number of dopants changes when the vapor density in the pick-up region is altered. This change, analyzed here, has quantitative consequences for the interpretation of data that are sensitive to host size, such as mass spectrometric, spectroscopic, and deflection measurements.
AuNPs synthesised in situ from self-assembled peptide hydrogels modulating peptide secondary structure
Authors: Huang Bin , Li Lingyi , Yan Fuzhen , Liu Fangjie , Zhang Jin , Zhong Linlin , Xu Wenlong
Published: February 2025

The disease caused by amyloidosis is thought to be due to the toxicity of the hydrophobic groups exposed by the β-sheet structure among amyloid oligomers. The non-specific binding of nanomaterials to proteins and peptides may be able to modulate the β-sheet structure. In this work, we designed an amphipathic peptide Fmoc-FFCKK-OH based on the amyloid peptide FF sequence in order to evaluate nanomaterials as amyloid aggregation regulators. Au3+ was used to modulate peptide self-assembly to form hydrogels and to form gold nanoparticles (AuNPs) in situ under the reduction of –SH. We simplified the complex process of structural transformation of proteins and peptides by constructing a hydrogel model. The transformation and aggregation behaviour of the secondary structure of peptides on the surface of AuNPs over time was investigated. Circular dichroism (CD) and surface-enhanced Raman scattering (SERS) were used to observe the transition from random coil to β-sheet with some α-helix within Fmoc-FFCKK-OH. This work not only simplifies the complexity of the study but also contributes to the understanding of the role of AuNPs in the regulation of amyloid formation and provides a research basis for AuNPs as amyloid regulators.
Trends in eastern blue groper (Achoerodus viridis) abundance along south-eastern Australia (New South Wales): the influence of latitude, climate change and potential depth refuges
Authors: Knott Nathan A. , Rees Matthew J. , Davis Tom R. , Harasti David , Malcolm Hamish A. , Taylor Matthew D. , Curley Belinda G. , Morris Stephen , Barrett Neville S. , Stuart-Smith Rick D. , Edgar Graham J. , Przeslawski Rachel
Published: February 2025

Context Eastern blue groper (Achoerodus viridis) is an iconic Australian fish and a trial prohibition of fishing for it has been implemented in New South Wales (NSW). A review of available data on this species is needed to inform future management. Aims To assess the temporal and spatial patterns in the abundance of A. viridis. Methods Data collected across four NSW bioregions from two systematic sampling programs, namely, baited remote underwater video (2010–23) and underwater visual census (2008–23), were analysed with the inclusion of two other common wrasse species as references. Key results Achoerodus viridis showed strong latitudinal variation: being least abundant in the warmer northern bioregion and peaking in abundance in the central Manning and southern Batemans Bioregions. Temporal trajectories for A. viridis were mixed with significant declines on shallow reefs in the Manning and Hawkesbury Bioregions, whereas abundances on deeper reefs were stable. Similar patterns of decline were observed for the two reference species, although both species were far more abundant than was A. viridis. Conclusions Achoerodus viridis, like other temperate wrasse, appears to be declining because of warming oceans, although depth may provide a thermal refuge Implications These analyses should assist decision-making for future management regulations for A. viridis.
Short-term impacts of operational fuel treatments on modelled fire behaviour and effects in seasonally dry forests of British Columbia, Canada
Authors: Rutherford Kea H. , Eskelson Bianca N. I. , Daniels Lori D. , LeMay Valerie , Greene Gregory A. , Gray Robert W.
Published: February 2025

Background In response to increasing risk of extreme wildfire across western North America, forest managers are proactively implementing fuel treatments. Aims We assessed the efficacy of alternative combinations of thinning, pruning and residue fuel management to mitigate potential fire behaviour and effects in seasonally dry forests of interior British Columbia, Canada. Methods Across five community forests, we measured stand attributes before and after fuel treatments in 2021 and 2022, then modelled fire behaviour and effects using the Fire and Fuels Extension to the Forest Vegetation Simulator. Key results For our study area, field measurements combined with fire behaviour modelling indicated: (1) low-intensity thinning from below reduced potential of passive crown fire, whereas high-intensity thinning reduced potential of passive and active crown fire; (2) pruning after thinning from below did not further reduce potential of passive crown fire; and (3) chipping or pile burning of residue fuel mitigated potential of passive crown fire, but fire effects associated with chipping remain a concern. Conclusions and implications There is limited prior research on the impacts of fuel treatments in western Canada. This research contributes to better understanding the potential impacts of fuel treatments in the fire-prone forests of interior British Columbia.
Intracranial substrates of meditation-induced neuromodulation in the amygdala and hippocampus
Authors: Maher Christina , Tortolero Lea , Jun Soyeon , Cummins Daniel D. , Saad Adam , Young James , Nunez Martinez Lizbeth , Schulman Zachary , Marcuse Lara , Waters Allison , Mayberg Helen S. , Davidson Richard J. , Panov Fedor , Saez Ignacio
Published: February 2025

Meditation is an accessible mental practice associated with emotional regulation and well-being. Loving-kindness meditation (LKM), a specific subtype of meditative practice, involves focusing one’s attention on thoughts of well-being for oneself and others. Meditation has been proven to be beneficial in a variety of settings, including therapeutic applications, but the neural activity underlying meditative practices and their positive effects are not well understood. It has been difficult to understand the contribution of deep limbic structures given the difficulty of studying neural activity directly in the human brain. Here, we leverage a unique patient population, epilepsy patients chronically implanted with responsive neurostimulation devices that allow chronic, invasive electrophysiology recording to investigate the physiological correlates of LKM in the amygdala and hippocampus of novice meditators. We find that LKM-associated changes in physiological activity were specific to periodic, but not aperiodic, features of neural activity. LKM was associated with an increase in γ (30 to 55 Hz) power and an alternation in the duration of β (13 to 30 Hz) and γ oscillatory bursts in both the amygdala and hippocampus, two regions associated with mood disorders. These findings reveal the nature of LKM-induced modulation of limbic activity in first-time meditators.
Black and Latinx workers reap lower rewards than White workers from years spent working in big cities
Authors: Buchholz Maximilian , Storper Michael
Published: February 2025

The large labor markets of big cities offer greater possibilities for workers to gain skills and experience through successively better employment opportunities. This “experience effect” contributes to the higher average wages that are found in big cities compared to the economy as a whole. Racial wage inequality is also higher in bigger cities than in the economy on average. We offer an explanation for this pattern, demonstrating that there is substantial racial inequality in the economic returns to work experience acquired in big cities. Using data from the National Longitudinal Survey of Youth, 1979 we find that each year of work experience in a big city increases Black and Latinx workers’ wages by about one quarter to half as much as White workers’ wages. A substantial amount of this inequality can be explained by further racial disparities in the benefits of high-skill work experience. This research identifies a heretofore unknown source of inequality that is distinctly urban in nature, and expands our knowledge of the challenges to reaching interracial wage equality.
ARHGEF17/TEM4 regulates the cell cycle through control of G1 progression
Authors: Prifti Diogjena Katerina , Lauzier Annie , Garand Chantal , Calvo Eva , Devillers Romain , Roy Suparba , Dos Santos Alexsandro , Descombes Laurence , Trudel Benjamin , Laplante Mathieu , Bordeleau François , Elowe Sabine
Published: February 2025

The Ras homolog (Rho) small GTPases coordinate diverse cellular functions including cell morphology, adhesion and motility, cell cycle progression, survival, and apoptosis via their role in regulating the actin cytoskeleton. The upstream regulators for many of these functions are unknown. ARHGEF17 (also known as TEM4) is a Rho family guanine nucleotide exchange factor (GEF) implicated in cell migration, cell–cell junction formation, and the mitotic checkpoint. In this study, we characterize the regulation of the cell cycle by TEM4. We demonstrate that TEM4-depleted cells exhibit multiple defects in mitotic entry and duration, spindle morphology, and spindle orientation. In addition, TEM4 insufficiency leads to excessive cortical actin polymerization and cell rounding defects. Mechanistically, we demonstrate that TEM4-depleted cells delay in G1 as a consequence of decreased expression of the proproliferative transcriptional co-activator YAP. TEM4-depleted cells that progress through to mitosis do so with decreased levels of cyclin B as a result of attenuated expression of CCNB1. Importantly, cyclin B overexpression in TEM4-depleted cells largely rescues mitotic progression and chromosome segregation defects in anaphase. Our study thus illustrates the consequences of Rho signaling imbalance on cell cycle progression and identifies TEM4 as the first GEF governing Rho GTPase-mediated regulation of G1/S.
ERG responses to high-frequency flickers require FAT3 signaling in mouse retinal bipolar cells
Authors: Avilés Evelyn C. , Wang Sean K. , Patel Sarina , Cordero Sebastian , Shi Shuxiang , Lin Lucas , Kefalov Vladimir J. , Goodrich Lisa V. , Cepko Constance L. , Xue Yunlu
Published: February 2025

Vision is initiated by the reception of light by photoreceptors and subsequent processing via downstream retinal neurons. Proper circuit organization depends on the multifunctional tissue polarity protein FAT3, which is required for amacrine cell connectivity and retinal lamination. Here, we investigated the retinal function of Fat3 mutant mice and found decreases in both electroretinography and perceptual responses to high-frequency flashes. These defects did not correlate with abnormal amacrine cell wiring, pointing instead to a role in bipolar cell subtypes that also express FAT3. The role of FAT3 in the response to high temporal frequency flashes depends upon its ability to transduce an intracellular signal. Mechanistically, FAT3 binds to the synaptic protein PTPσ intracellularly and is required to localize GRIK1 to OFF-cone bipolar cell synapses with cone photoreceptors. These findings expand the repertoire of FAT3’s functions and reveal its importance in bipolar cells for high-frequency light response.
Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with KRISS, September 2024
Authors: Viallon Joële , Idrees Faraz , Moussay Philippe , Wielgosz Robert , Lee Sangil , Lee Hwan
Published: February 2025

Main text

As part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Korea maintained by the Korea Research Institute of Standards and Science (KRISS) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol mol-1 to 500 nmol mol-1.

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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Urban power line extraction from mobile LiDAR point clouds based on local line-plane seperation model and global refinement
Authors: Li Jie , Chen Jiwen , Huang Min , Li Li , Tu Jingmin , Li Ji , Hu Tu
Published: February 2025

Power line extraction from three-dimensional (3D) point clouds is a key step for power inspection. However, the power line is intertwined and covered with trees and other objects in the urban area, which brings a tremendous challenge to its extraction. This article proposed a local-to-global method to extract power lines from mobile Light Detection and Ranging point clouds based on multiple characteristics. Firstly, initial point clouds clusters are selected through data preprocessing. Secondly, given the linearity and independence of the power line, we innovatively design a local line-plane separation modeling to divide the point clouds into high-confidence power line points, non-power line points, and unconfirmed points. Then, a novel global energy function is designed for the graph cut model according to the long linear and short radius characteristics of the power line. The proposed method has been tested on Toronto 3D and WuHan Avenue datasets. The average Precision, Recall, and F1score can reach up to 0.92, 0.73, and 0.79 respectively, which is superior to state-of-the-art approaches. The result demonstrates the efficacy and robustness of our proposed approach in extracting power lines within urban environments using a mobile laser scanning system.
Fixed-focus laser triangulation simultaneously measures the morphology and color of object
Authors: Zheng Yinan , Liu Huazhen , Ding Chunxu , Qu Yuan , Yang Jiamiao , Shao Rongjun
Published: February 2025

Simultaneously measuring the surface morphology and color of a sample is crucial for full-color 3D printing and digitization of cultural artifacts. However, traditional methods are susceptible to the variations in the measurement angle and illumination condition, making it difficult to balance the color fidelity and spatial accuracy. Here, we propose a laser triangulation method that is implemented with a fixed focus, dark-field illumination, and data-driven spectral classification. With a fixed focus, this method measures the height of surface by analyzing the shape of reflected light spot. The dark-field illumination diminishes the background contributed by the specular reflection of white light, enabling an accurate spectral measurement. The data-driven spectral classification algorithm establishes color dataset for each sample, and ensures a precise color recognition through principal component analysis dimensionality reduction and K-nearest neighbor classification. In our experiment, this method achieved an axial resolution of 5.1 μm. The color classification accuracy was as high as 99.79% on ColorChecker cards and 96.03% on Pantone color match cards. Three samples were reconstructed and evaluated to validate this method, the mean absolute error of the morphology measurements did not exceed 25 μm, and the color difference (CIE2000) does not exceed 1.0, confirming its ability to accurately measure the surface morphology and color simultaneously.
DarkMatcher: an efficient self-supervised network for image matching in extremely dark environments
Authors: Zhang Jiawei , Wang Peng , Li Yue , Li Lin , Song Qingrui , He Rongfang , Fu Luhua
Published: February 2025

Low-light visual perception problems, such as night simultaneous localization and mapping or structure-from-motion have attracted increasing attention, and the performance of keypoint detection and local feature description play a crucial role. Many traditional algorithms and machine learning methods have been widely used to detect and describe local features. However, the performance of the existing techniques in the face of highly low-light scenes will be drastically degraded, resulting in subsequent practical application needs that cannot be met. Therefore, an efficient self-supervised deep learning model DarkMatcher is proposed, which can directly detect and describe features from images in extremely dark environments in an end-to-end way. This model consists of a backbone based on new dynamic deformable convolutional blocks and a novel DarkMatcher module that combines multiple attention mechanisms to realize cross-scale feature information interaction. The former enhances the feature extraction capability of the model for low-light environment images. The latter effectively strengthens the matching ability of extremely dark environments and weak texture areas, and further improves the feature matching accuracy in low-light scenes. In addition, transfer learning and real-time training strategies are used to enhance the generalization and feature representation capabilities of the model. Many experimental results indicate that DarkMatcher possesses the best matching performance and robustness for feature points in extremely dark environment, with an average matching accuracy of 71.24% and an average execution time of 51 ms for each pair of images. Besides, the visual pose estimation experiment has also obtained good results as validation.
Extensive adjustment of magnetic field on plasma density and ion incidence angle in radio frequency discharge
Authors: Ma Fang-Fang , Zhang Quan-Zhi , Schulze Julian , Cui Yu-Meng , Wang You-Nian
Published: February 2025

The impact of an inhomogeneous magnetic field generated by supplementary direct current (DC) coils on the uniformity of capacitively coupled discharges is examined utilizing a two-dimensional implicit particle-in-cell/Monte Carlo model. Typically, at low pressure, the radial density distribution of plasma is characterized by a high density at the center of the chamber and a lower density near the periphery. This results in non-uniform radial plasma density profiles and large ion impact angles at the electrode. We find that placing a DC coil above the chamber produces a non-uniform static magnetic field, which facilitates the transport of plasma species toward the electrode periphery, resulting in a more uniform plasma density distribution. Nonetheless, this approach leads to a decrease in central density and adversely affects the ion incident angles near the chamber’s center. Consequently, this compromise undermines both the efficiency and uniformity of processes occurring in the central region of the chamber. To overcome these limitations, we propose innovative coil configurations, specifically dual direct current (DC) coils comprising an inner and an outer coil. The outer coil, situated above the chamber, has a larger radius, while the inner coil, positioned either above or below the chamber, has a smaller radius. Additionally, the currents in the inner and outer coils flow in opposite directions. Our findings indicate that the outer coil predominantly governs the density distribution across the entire electrode surface, while the inner coil allows for precise adjustment of the plasma density near the discharge center. Therefore, by adjusting the currents of the outer and inner coils, significant improvements can be achieved in both the uniformity of plasma density and the vertical alignment of the ion angles above the electrode. These factors are critical for the fabrication of high aspect ratio microelectronic structures.
Integrated Electrically Small Monopole and Slotted Array Antenna Design for Next-Generation Microwave and mm-wave Wireless Systems
Authors: Kamruzzaman M.M , Annadurai C , Nelson I , Nirmala Devi K , Ramkumar Raja Manoharan
Published: February 2025

This paper presents a novel co-design approach for wireless applications, integrating mm-wave and microwave technologies. The design features two antennas where a slotted waveguide array is fabricated using 3D-printing technology with an AlMg10Si alloy resonating at mm-wave frequency band, while a printed monopole antenna resonating at microwave frequency band shares a common ground plane with the slotted waveguide array. The electrically small printed monopole is realized on an FR4 substrate, is suitable for WLAN bands, and achieves ease of integration with the antenna at the Ka-band owing to the low profile. The co-design approach is particularly advantageous for wireless applications as it enables the seamless integration of different frequency bands, enhancing system versatility and performance. The antenna achieves dual frequency band operation covering the Impedance bandwidth of 15.27% (5.08-5.92) and 14.56% (26.48-30.64) at microwave and Ka-band frequencies, respectively. The innovative use of materials and advanced fabrication techniques also underscores the design's potential for diverse high-performance wireless applications.
Impact of bivariate gaussian potentials on quantum walks for spatial search
Authors: de L Marquezino Franklin , Santos Raqueline A M
Published: February 2025

Quantum search algorithms are crucial for exploring large solution spaces, but their robustness to environmental perturbations, such as noise or disorder, remains a critical challenge. We examine the impact of biased disorder potentials modeled by a bivariate Gaussian distribution function on the dynamics of quantum walks in spatial search problems. Building on the Ambainis-Kempe-Rivosh (AKR) model for searching on a two-dimensional grid, we incorporate potential fields to investigate how changes in standard deviation and normalization of the bivariate Gaussian function impact the performance of the search algorithm. Our results show that the quantum walk closely mirrors the AKR algorithm when the standard deviation is small but exhibits a rapid decay in success probability as the standard deviation increases. This behavior demonstrates how the bivariate Gaussian can effectively model a noisy oracle within the AKR algorithm. Additionally, we compare the AKR-based model with an alternative quantum walk model using a Hadamard coin and standard shift. These findings contribute to understanding the robustness of quantum walk search algorithms, and provide insights into how quantum walks can be applied to optimization algorithms.
Confronting new NICER mass-radius measurements with phase transition in dense matter and twin compact stars
Authors: Li Jia Jie , Sedrakian Armen , Alford Mark
Published: February 2025

The (re)analysis of data on the X-ray emitting pulsars PSR J0030+0451
and J0740+6620, as well as new results on PSR J0437-4715 and J1231-1411,
are confronted with the predictions of the equation of state (EoS)
models allowing for strong first-order phase transition for the mass-radius
(M-R) diagram. We use models that are based on a covariant density
functional (CDF) EoS for nucleonic matter at low densities and a quark
matter EoS, parameterized by the speed of sound, at higher densities.
To account for the variations in the ellipses for PSR J0030+0451 obtained
from different analyses, we examined three scenarios to assess their
consistency with our models, focusing particularly on the potential
formation of twin stars. We found that in two scenarios, where the
ellipses for PSR J0030+0451 and J0437-4715 with masses close to
the canonical mass ∼ 1.4 M
⊙ are significantly separated,
our models allow for the presence of twin stars as a natural explanation
for potential differences in the radii of these stars.
A global fit of non-relativistic effective dark matter operators including solar neutrinos
Authors: Avis Kozar N.P. , Scott Pat , Vincent A.C.
Published: February 2025

We perform a global fit of dark matter interactions with nucleons
using a non-relativistic effective operator description, considering both direct detection and
neutrino data. We examine the impact of combining the direct detection experiments CDMSlite,
CRESST-II, CRESST-III, DarkSide-50, DarkSide-50-S2-Only, LUX, LZ, PandaX-II, PandaX-4T, PICO-2L,
PICO-60, SIMPLE, XENON100, and XENON1T along with neutrino data from IceCube, ANTARES, DeepCore,
and Super-Kamiokande. While current neutrino telescope data lead to increased sensitivity
compared to underground nuclear scattering experiments for dark matter masses above 100 GeV, our
future projections show that the next generation of underground experiments will significantly
outpace solar searches for most dark matter-nucleon elastic scattering interactions.
Evolving disorder and chaos enhances the wave speed of elastic waves
Authors: Ahumada M , Trujillo L , Marín J F
Published: February 2025

Static or frozen disorder, characterised by spatial heterogeneities, influences diverse complex systems, encompassing many-body systems, equilibrium and nonequilibrium states of matter, intricate network topologies, biological systems, and wave-matter interactions. While static disorder has been thoroughly examined, delving into evolving disorder brings increased intricacy to the issue. An example of this complexity is the observation of stochastic acceleration of electromagnetic waves in evolving media, where noisy fluctuations in the propagation medium transfer effective momentum to the wave. Here, we investigate elastic wave propagation in a one-dimensional heterogeneous medium with diagonal disorder. We examine two types of complex elastic materials: one with static disorder, where mass density randomly varies in space, and the other with evolving disorder, featuring random variations in both space and time. Our results indicate that evolving disorder enhances the propagation speed of Gaussian pulses compared to static disorder. Additionally, we demonstrate that the enhanced speed effect also occurs when the medium evolves chaotically rather than randomly over time. The latter establishes that evolving randomness is not a unique prerequisite for observing the enhanced transport of wavefronts, introducing the concept of chaotic speed enhancement of waves in complex media.
Corrigendum: Observation and modelling of asymmetric loading on large offshore wind turbines in wake conditions (J. Phys.: Conf. Ser. 2767 092092)
Authors: Bernard V , Andersen S J , Murcia Leon J P , Beaudet L , Verelst D , Iliopoulos A
Published: February 2025

Please see Article PDF for corrigendum text.
Optimizing gamma radiation shielding in Pr3+ doped boro-tellurite glasses: a study of attenuation properties and performance
Authors: Sharma Surbhi , Verma Neetu
Published: February 2025

A series of Pr3+ doped boro tellurite glass samples are synthesized using melt quenching technique and investigated for their potential in gamma ray shielding applications. The amorphous nature of prepared samples is confirmed through X-Ray diffraction technique. The shielding characteristics of prepared glass samples were assessed by determining various parameters, including the linear attenuation coefficient (LAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and mass attenuation coefficient (MAC) across the energy range of 15 keV to 15 MeV. The significant decrease in the linear attenuation coefficient (LAC) for all the prepared samples indicates their enhanced radiation attenuation capabilities. Furthermore, it was observed that LAC values are nearly consistent in the energy range from 1.5 MeV<E<15 MeV, for all the prepared samples, demonstrating its independence from the atomic number of the sample. Additionally, HVL values decreases in the energy range from 8 MeV -15 MeV for all the prepared samples which underscores its exceptional efficacy in radiation shielding. This significant reduction in HVL indicates that the Pr3+- doped glass provides superior attenuation of gamma radiation, making it an excellent choice for applications where effective radiation protection is critical. A sharp peak at 40KeV is observed in Zeff graph showing the dominance of Te absorption edge. The higher values of Zeff at 0.6 MeV for all the prepared samples in this study are evident compared to those reported for lead borate, lead silicate, and lead phosphate in the literature. The current study highlights the effectiveness of the prepared samples as gamma radiation shielding materials.
Tribological behavior investigation of enset/sisal hybrid reinforced composites
Authors: Bekele A E , Lemu H G
Published: February 2025

Easy availability, biodegradability and exceptional performance of natural fibers are among the attractive factors for their wide utilization. However, several factors such as fiber type, shape and size of fibers, fiber-matrix ratios, reinforcement orientation with respect to the loading direction, preparation method and type of treatment used highly influence their performance. The present study investigates the tribological behavior of polyester composites developed by hybridizing two locally available inexpensive plant fibers: enset and sisal. Both woven and unidirectional 5 wt% alkali treated hybrid fibers with 1:1 ratio was used to develop the hybrid composite using hand lay-up and compression molding. The tribological property was tested using pin-on-disc tribo-testing machine. The wear condition was studied in dry condition by varying the applied load (10, 20 and 30 N) and sliding speed (0.5, 1 and 1.5 m/s). Analysis of the morphology of the worn surface was conducted using 3D microscopy scanning electron microscopy images. The coefficient of friction and the wear rate results indicate the suitability of the selected hybrid composite for use as frictional material such as brake applications.
Finite element modeling and analysis of lightning protection poles using electrically conductive concrete
Authors: Yu X M , Cai W X , Wang P F
Published: February 2025

In order to study the load-bearing performance of electrically conductive concrete lightning protection poles, a finite element model of electrically conductive concrete lightning protection poles was established and the deformation capacity and load-bearing performance of the poles were analyzed using ABAQUS software. The results show that the use of prestressed reinforcement can significantly improve the bending capacity and ultimate deformation of the pole. Increasing the reinforcement ratio and outer diameter of lightning protection poles can improve the bending load capacity, but increasing the wall thickness has limited effect on enhancing the bending load capacity of lightning protection poles. This study can provide a theoretical basis for the technical application of electrically conductive concrete lightning protection poles.
Investigating the corrosion rate and hardness of mild steel jointed by arc and CO2 welding processes
Authors: Mugwagwa L. , Pita M. , Lebea L.
Published: February 2025

Corrosion is the degradation of materials, usually metals, owing to chemical reactions with the environment which results in a functional failure of components. This research paper investigates the corrosion rate and hardness of mild steel jointed by Arc and CO2 welding processes. Mild steel samples with double V-grooves were prepared prior to CO2 and arc welding processes. In this study, corrosion experiments were conducted to determine the corrosion rate of both samples, namely, weight loss and linear polarization method. Furthermore, the hardness test was conducted on welded samples according to the ASTM E384 standard. The results show that CO2 welding process produced the hardest weld of 193.3 HV, which was 26.4% harder than the arc welding process. The lowest corrosion rate was obtained for the sample welded by CO2 welding process and was reported to be 0.1817 mg/cm2.h.
Amplified summer wind stilling and land warming compound energy risks in Northern Midlatitudes
Authors: Zhang Gan
Published: February 2025

Wind energy plays a critical role in mitigating climate change and meeting growing energy demands. However, the long-term impacts of anthropogenic warming on wind resources, particularly their seasonal variations and potential compounding risks, remain understudied. Here we analyze large-ensemble climate simulations in high-emission scenarios to assess the projected changes in near-surface wind speed and their broader implications. Our analyses show robust wind changes including a decrease of wind speed (i.e. stilling) up to ∼15% during the summer months in Northern Midlatitudes. This stilling is linked to amplified warming of the midlatitude land and the overlying troposphere. Despite regional and model uncertainties, robust signals of warming-induced wind stilling will likely emerge from natural climate variations in the late 21st century under the high-emission scenarios. Importantly, the summertime wind stilling coincides with a projected surge in cooling demand, and their compounding may disrupt the energy supply-demand balance earlier. These findings highlight the importance of considering the seasonal responses of wind resources and the associated climate-energy risks in a warming climate. By integrating these insights into future energy planning decisions, we can better adapt to a changing climate and ensure a reliable and resilient energy future.
Numerical investigation of indirect parallel PVT solar systems using MATLAB/simulink
Authors: Saidi Sirine , Brahim Taoufik , Jemni Abdelmajid
Published: February 2025

In this paper, an original numerical investigation of indirect parallel photovoltaic/thermal system integration using Matlab/Simulink is carried out. The added value is to evaluate the potential use of integrated PVT (Photovoltaic-Thermal) solar systems in residential applications and the possibility of controlling and investigating their performance to optimize the results under weather conditions throughout the year. A substantial number of annual simulations have been conducted to encompass the best performance using each control, with an emphasis on two configurations of cooling approaches. Results show that an optimal mass flow rate of about 0.0125 kg/s for both collector and storage tank pumps was found. For the direct cooling method, results reveal an increase in overall system efficiency of the order of 41.4%. In addition, the paper compares the PVT system with a stand-alone PVT collector, and the results indicate that integrated PVT leads to a relative improvement in electrical and thermal efficiency of about 7.89% and 24.62%, respectively.
Forecasting the electricity usage in single-family housings of a case study via kho-kho optimization algorithm
Authors: Guo Jun , Chen Maoyuan , Li Yuyang , Feng Sibo , Fu Guangyu
Published: February 2025

Nowadays, the consumption of energy has increased on an unprecedented scale, so it is of primary importance to forecast energy use via designing energy usage simulation systems. The challenge of energy management within buildings can have implications for energy management at a broader scale (national power grid). Furthermore, the application of various algorithms may enhance the comprehension of these dynamics. In this paper, a kho-kho-based Optimization Algorithm Numerical Moment Matching (kho-kho-NMM) method is employed for predicting the electricity usage in a set of single-family dwellings using the key features. Hence, for the residences that illustrate the systematic characteristics of the database, a group of indices including their correlated weights is obtained. The DesignBuilder software is used for developing the modeling of energy. By integrating these procedures, the buildings’ energy performance is evaluated in a case study, Toronto in Iowa. This method is able to be employed for making a small set of usual dwellings in order to demonstrate the energy performance in a far larger set of residences. A significant aspect of this research is its concentrated examination of private housing databases, positing that there are fundamental differences in energy consumption behaviors between residential and commercial structures. This can lead to identifying systematic relationships and reduces the complexity of calculations by focusing on a limited set of specialized housing types for energy behavior analysis within extensive datasets. The outcomes depict that the forecasted electricity usage within a year is 10,315 kWh being in 4% of the experimental data. What is more, the mean bias error (MBE) of the forecasted electricity usage over a month is 2.2% and the Deviation Constant with residuals (the Root Mean Square Error (DC-RMSE)) is 10.6%. Overall, the research findings can result in achieving a a methodology under virtually less calculation that can result in the outcomes’ conserved efficacy whenever the computing period and cost are decreasing.
The National Security Black Box
Authors: Deeks Ashley S
Published: February 2025

Chapter 1 explains why U.S. national security operations are generally less regulated and harder to oversee than other governmental activities, which is a problem for a democratic system. Even with traditional checks imposed by Congress and the courts, much that happens inside the national security arena remains a black box to outside observers. However, there are a burgeoning set of nontraditional secrecy surrogates, including foreign allies, technology companies, and U.S. states that can help chisel away at the black box nature of U.S. national security. The chapter shows how all of these actors can help reduce the opacity of the national security black box but cannot eliminate it.