bluuebunny/crossref_metadata_2025 huggingface dataset:
Relations between Reynolds stresses and their dissipation rates during premixed flame–wall interaction within turbulent boundary layers
Authors: Ahmed Umair , Ghai Sanjeev Kumar , Chakraborty Nilanjan
Published: April 2024

A direct numerical simulation (DNS) database for head-on quenching of premixed flames propagating across turbulent boundary layers representative of friction Reynolds numbers, Reτ, of 110 and 180 has been utilized to analyze the interrelation between Reynolds stresses and their dissipation rates during flame–wall interaction. The Reynolds stresses and their dissipation rates exhibit significant deviations from the corresponding non-reacting flow profiles within the flame brush and in the burned gas region. This behavior is prominent for the components in the wall-normal direction because the mean direction of flame normal acceleration due to thermal expansion aligns with the wall-normal direction in this configuration. The anisotropy of Reynolds stresses and their dissipation rate tensors have been found to be qualitatively similar, but the anisotropic behavior weakens with increasing Reτ. However, the components of the anisotropy tensors of Reynolds stresses and viscous dissipation rate are not related according to a linear scaling, and thus, the models based on this assumption do not successfully capture the viscous dissipation rate components obtained from the DNS data. By contrast, a model, which includes the invariants of the anisotropy tensor of Reynolds stresses and satisfies the limiting conditions, has been found to capture especially the diagonal components of the viscous dissipation rate tensor more successfully for both non-reacting and reacting cases considered in this work. However, the quantitative prediction of this model suffers for the components in the wall-normal direction for lower values of Reτ, but the performance of this model improves with an increase in Reτ.
A national accounting framework for fire and carbon dynamics in Australian savannas
Authors: Paul Keryn I. , Roxburgh Stephen H.
Published: April 2024

Background Tropical savannas represent a large proportion of the area burnt each year globally, with growing evidence that management to curtail fire frequency and intensity in some of these regions can contribute to mitigation of climate change. Approximately 25% of Australia’s fire-prone tropical savanna region is currently managed for carbon projects, contributing significantly to Australia’s National Greenhouse Gas Inventory. Aims To improve the accuracy of Australia’s national carbon accounting model (FullCAM) for reporting of fire emissions and sequestration of carbon in savanna ecosystems. Methods Field data from Australian savannas were collated and used to calibrate FullCAM parameters for the prediction of living biomass, standing dead biomass and debris within seven broad vegetation types. Key results Revised parameter sets and improved predictions of carbon stocks and fluxes across Australia’s savanna ecosystems in response to wildfire and planned fire were obtained. Conclusions The FullCAM model was successfully calibrated to include fire impacts and post-fire recovery in savanna ecosystems. Implications This study has expanded the capability of FullCAM to simulate both reduced emissions and increased sequestration of carbon in response to management of fire in tropical savanna regions of Australia, with implications for carbon accounting at national and project scales.
Linkage among the neutron-skin thickness of 208Pb and nuclear symmetry energy using heavy particle radioactivity
Authors: Kaur Manpreet , Patra S K , Raina P K
Published: April 2024

The nuclear symmetry energy (NSE) is a linchpin in deciphering the behavior of matter in a wider domain extending from the characteristics of exotic nuclei to those of neutron stars in the cosmos. Therefore, it is crucial to utilize potential probes to constrain the NSE and its slope parameter L(ρ
0). In this work, we put forth the heavy particle radioactivity (HPR) as a probable bridge among the slope of NSE (L(ρ
0)) and neutron-skin thickness of 208Pb (R
skin
208), which serves to put constrain on the L(ρ
0) value. The NSE and its slope parameter are determined from the single nucleon potential of asymmetric nuclear matter exploiting the analytical relationship between these quantities. The isovector/symmetry potential component of the single nucleon potential is derived through HPR for varying R
skin
208 by employing the heavy particle/cluster densities and core densities from the relativistic mean field model in conjunction with M3Y nucleon–nucleon interaction. It facilitates in constraining the L(ρ
0) value and neutron skin of finite nuclei using HPR as a linkage, where heavy cluster and core densities of standard Fermi form are considered. The constrained value of L(ρ

o
) is 45 ± 8 MeV, which aligns with other estimations derived from nuclear mass measurements, dipole polarizability measurements, and astrophysical data.
A non-invasive approach to skin cancer diagnosis via graphene electrical tattoos and electrical impedance tomography
Authors: Lee Hannah , Johnson Zane , Denton Spencer , Liu Ning , Akinwande Deji , Porter Emily , Kireev Dmitry
Published: April 2024

Objective. Making up one of the largest shares of diagnosed cancers worldwide, skin cancer is also one of the most treatable. However, this is contingent upon early diagnosis and correct skin cancer-type differentiation. Currently, methods for early detection that are accurate, rapid, and non-invasive are limited. However, literature demonstrating the impedance differences between benign and malignant skin cancers, as well as between different types of skin cancer, show that methods based on impedance differentiation may be promising. Approach. In this work, we propose a novel approach to rapid and non-invasive skin cancer diagnosis that leverages the technologies of difference-based electrical impedance tomography (EIT) and graphene electronic tattoos (GETs). Main results. We demonstrate the feasibility of this first-of-its-kind system using both computational numerical and experimental skin phantom models. We considered variations in skin cancer lesion impedance, size, shape, and position relative to the electrodes and evaluated the impact of using individual and multi-electrode GET (mGET) arrays. The results demonstrate that this approach has the potential to differentiate based on lesion impedance, size, and position, but additional techniques are needed to determine shape. Significance. In this way, the system proposed in this work, which combines both EIT and GET technology, exhibits potential as an entirely non-invasive and rapid approach to skin cancer diagnosis.
Patient-independent, MHD-robust R-peak detection for retrospective gating in cardiac MRI imaging
Authors: Ganassin Sara , Galli Alessandra , Ouzounov Sotir , Narduzzi Claudio
Published: April 2024

Objective. In cardiovascular magnetic resonance imaging, synchronization of image acquisition with heart motion (called gating) is performed by detecting R-peaks in electrocardiogram (ECG) signals. Effective gating is challenging with 3T and 7T scanners, due to severe distortion of ECG signals caused by magnetohydrodynamic effects associated with intense magnetic fields. This work proposes an efficient retrospective gating strategy that requires no prior training outside the scanner and investigates the optimal number of leads in the ECG acquisition set. Approach. The proposed method was developed on a data set of 12-lead ECG signals acquired within 3T and 7T scanners. Independent component analysis is employed to effectively separate components related with cardiac activity from those associated to noise. Subsequently, an automatic selection process identifies the components best suited for accurate R-peak detection, based on heart rate estimation metrics and frequency content quality indexes. Main results. The proposed method is robust to different B0 field strengths, as evidenced by R-peak detection errors of 2.4 ± 3.1 ms and 10.6 ± 15.4 ms for data acquired with 3T and 7T scanners, respectively. Its effectiveness was verified with various subject orientations, showcasing applicability in diverse clinical scenarios. The work reveals that ECG leads can be limited in number to three, or at most five for 7T field strengths, without significant degradation in R-peak detection accuracy. Significance. The approach requires no preliminary ECG acquisition for R-peak detector training, reducing overall examination time. The gating process is designed to be adaptable, completely blind and independent of patient characteristics, allowing wide and rapid deployment in clinical practice. The potential to employ a significantly limited set of leads enhances patient comfort.
LUNet: deep learning for the segmentation of arterioles and venules in high resolution fundus images
Authors: Fhima Jonathan , Van Eijgen Jan , Billen Moulin-Romsée Marie-Isaline , Brackenier Heloïse , Kulenovic Hana , Debeuf Valérie , Vangilbergen Marie , Freiman Moti , Stalmans Ingeborg , Behar Joachim A
Published: April 2024

Objective. This study aims to automate the segmentation of retinal arterioles and venules (A/V) from digital fundus images (DFI), as changes in the spatial distribution of retinal microvasculature are indicative of cardiovascular diseases, positioning the eyes as windows to cardiovascular health. Approach. We utilized active learning to create a new DFI dataset with 240 crowd-sourced manual A/V segmentations performed by 15 medical students and reviewed by an ophthalmologist. We then developed LUNet, a novel deep learning architecture optimized for high-resolution A/V segmentation. The LUNet model features a double dilated convolutional block to widen the receptive field and reduce parameter count, alongside a high-resolution tail to refine segmentation details. A custom loss function was designed to prioritize the continuity of blood vessel segmentation. Main Results. LUNet significantly outperformed three benchmark A/V segmentation algorithms both on a local test set and on four external test sets that simulated variations in ethnicity, comorbidities and annotators. Significance. The release of the new datasets and the LUNet model (www.aimlab-technion.com/lirot-ai) provides a valuable resource for the advancement of retinal microvasculature analysis. The improvements in A/V segmentation accuracy highlight LUNet's potential as a robust tool for diagnosing and understanding cardiovascular diseases through retinal imaging.
Real-time regurgitation estimation in percutaneous left ventricular assist device fully supported condition using an unscented Kalman filter
Authors: Yin Anyun , Wen Biyang , Xie Qilian , Dai Ming
Published: April 2024

Objective. Significant aortic regurgitation is a common complication following left ventricular assist device (LVAD) intervention, and existing studies have not attempted to monitor regurgitation signals and undertake preventive measures during full support. Regurgitation is an adverse event that can lead to inadequate left ventricular unloading, insufficient peripheral perfusion, and repeated episodes of heart failure. Moreover, regurgitation occurring during full support due to pump position offset cannot be directly controlled through control algorithms. Therefore, accurate estimation of regurgitation during percutaneous left ventricular assist device (PLVAD) full support is critical for clinical management and patient safety. Approach. An estimation system based on the regurgitation model is built in this paper, and the unscented Kalman filter estimator (UKF) is introduced as an estimation approach. Three offset degrees and three heart failure states are considered in the investigation. Using the mock circulatory loop experimental platform, compare the regurgitation estimated by the UKF algorithm with the actual measured regurgitation; the errors are analyzed using standard confidence intervals of ±2 SDs, and the effectiveness of the mentioned algorithms is thus assessed. The generalization ability of the proposed algorithm is verified by setting different heart failure conditions and different rotational speeds. The root mean square error and correlation coefficient between the estimated and actual values are quantified and the statistical significance of accuracy differences in estimation is illustrated using one-way analysis of variance (One-Way ANOVA), which in turn assessed the accuracy and stability of the UKF algorithm. Main results. The research findings demonstrate that the regurgitation estimation system based on the regurgitation model and UKF can relatively accurately estimate the regurgitation status of patients during PLVAD full support, but the effect of myocardial contractility on the estimation accuracy still needs to be taken into account. Significance. The proposed estimation method in this study provides essential reference information for clinical practitioners, enabling them to promptly manage potential complications arising from regurgitation. By sensitively detecting LVAD adverse events, valuable insights into the performance and reliability of the LVAD device can be obtained, offering crucial feedback and data support for device improvement and optimization.
Design, analysis, and testing of a variable-stiffness soft grabbing robot coupling particle jamming and layer jamming
Authors: Xu Fengyu , Ma Kaiwei , He Xiangming , Wei Miaohang , Hu Chaobin
Published: April 2024

Variable-stiffness soft robots feature high flexibility in motion and high stiffness in task execution, so they are in wide demand. A coupled variable stiffening method and actuator structures based on layer jamming and particle jamming were developed. The influences of different coupled modes of particles and layers on variable stiffening were evaluated, and coupled variable-stiffness soft actuators were designed. Then, the finite element method was used to simulate the multi-airbag driving structure and variable-stiffness mechanical models were established for three coupled structures to optimize parameters influencing the stiffness. Furthermore, the prototypes of the coupled variable-stiffness soft actuators were prepared, and the test platform was built to estimate the bending performance and variable stiffening capacity. Finally, a soft grabbing robot was prepared using the coupled variable-stiffness soft actuator and application tests were performed. The theoretical analysis and test results show that the soft grabbing robot can grab objects in diverse shapes and the maximum mass of objects that can be grasped is 1.25 kg, which verifies the variable stiffening capacity of the coupled soft actuator. The research provides new theoretical and technological support for the design and application of variable-stiffness soft robots.
A wind-driven rotating micro-hybrid nanogenerator for powering environmental monitoring devices based on a brush-type triboelectric unit
Authors: Zhu Yongqiang , Zhang Long , Zhang Yuhan , Zhao Yu , Zhou Guangyao , Yu Shiyuan , Duan Shuai , Zhang Pingxia
Published: April 2024

The rapid rise of the IoT (Internet of Things) technology and microelectronics technology has promoted the development of sensors to ultra-low power consumption. However, for conventional wired power supply and chemical battery power supply, there are difficulties in wiring, inconvenient battery replacement and environmental pollution problems, so there is an urgent need for a green power supply. The low cost and simple structure of TENG (Triboelectric nanogenerator) have attracted much attention from researchers. However, for most of the existing TENG, there are some problems such as narrow operating frequency range, short life of TENG, insufficient traditional flexible friction contact, and serious wear of rigid friction contact. Herein, we propose a rotary brush-type triboelectric-electromagnetic hybrid nanogenerator. Through the experimental tests, the TENG part can output the maximum power of 0.88 mW under the external load of 8 MΩ at 400 rpm (wind speed of about 8.3 m/s). The EMG (Electromagnetic Generator) part can output the maximum power of 15.5 mW under external load of 360 Ω. The LED lighting test proves that the generator broadens the frequency of energy harvesting. In the capacitor charging test, the high voltage characteristics of tribological power generation play the advantages of continuous voltage boost, and the high current characteristics of electromagnetic power generation play the advantages of high power. The hybrid nanogenerator can realize the wind energy harvesting under the broadband wind speed of 3 m/s~14 m/s. At a wind speed of 5.6 m/s, the hybrid nanogenerator ran at about 225 rpm and successfully powered the anemometer after 21 s. After 80,000 cycles, the maximum open circuit voltage only drops by 5.6%, which proves that the rotary TENG unit has a long generation life, and can realize the harvesting of wind energy and the power supply of wind speed sensor.
Superconducting in-memory computing architecture coupling with memristor synapses for binarized neural networks
Authors: Xu Zuyu , Liu Yu , Wu Zuheng , Zhu Yunlai , Wang Jun , Yang Fei , Dai Yuehua
Published: April 2024

In-memory computing electronic components offer a promising non-von Neumann strategy to develop energy-efficient and high-speed hardware systems for artificial intelligence (AI). However, the implementation of conventional electronic hardware demands a huge computational and power budget, thereby limiting their wider application. In this work, we propose a novel superconducting in-memory computing architecture by coupling the memristor device. Leveraging the phase transition of the superconductor induced by external applied Joule power, we can modulate the state of the bottom superconductor based on memristor resistive states and applied voltages, enabling the execution of in-memory computing operations. We then successfully implement vector-matrix multiplication of input and output signals within the designed array, facilitating its integration into AI systems. Constructing a binarized neural network with superconductor-memristor arrays achieves a high level of accuracy, approximately 97%, in handwritten number classification. Through an evaluation of power consumption in our proposed architecture, we find a remarkable ∼48 400× advantage in power efficiency compared to typical memristor systems. This marks the inaugural demonstration of a superconducting in-memory computing architecture through memristor coupling, offering a promising hardware platform for various AI systems with superior energy efficiency and computing capacity.
Parameter space of leptogenesis in polynomial inflation
Authors: Drees Manuel , Xu Yong
Published: April 2024

Polynomial inflation is a very simple and well motivated
scenario. A potential with a concave “almost” saddle point at
field value ϕ = ϕ
0 fits well the cosmic microwave
background (CMB) data and makes testable predictions for the running
of the spectral index and the tensor to scalar ratio. In this work we analyze leptogenesis in the polynomial inflation framework. We delineate the allowed parameter space giving rise to the correct baryon asymmetry as well
as being consistent with data on neutrino oscillations. To that end
we consider two different reheating scenarios. (i) If the inflaton
decays into two bosons, the reheating temperature can be as high as
 T
rh ∼ 1014 GeV without spoiling the flatness of the
potential, allowing vanilla N
1 thermal leptogenesis to work if
 T
rh > M
1 where N
1 is the lightest right-handed neutrino and
 M
1 its mass. Moreover, if the dominant decay of the inflaton is
into Higgs bosons of the Standard Model, we find that rare
three-body inflaton decays into a Higgs boson plus one light and
one heavy neutrino allow leptogenesis even for T
rh < M
1 if the
inflaton mass is of order 1012 GeV or higher; in the polynomial
inflation scenario this requires ϕ
0 ≳ 2.5 MP
. This
novel mechanism of non-thermal leptogenesis is quite generic, since
the coupling leading to the three-body final state is required in
the type I see-saw mechanism. (ii) If the inflaton decays into
two fermions, the flatness of the potential implies a lower
reheating temperature. In this case inflaton decay to two N
1 
still allows successful non-thermal leptogenesis if
 ϕ
0 ≳ 0.1 MP
and T
rh ≳ 106 GeV.
Evaporation barrier for dark matter in celestial bodies
Authors: Acevedo Javier F. , Leane Rebecca K. , Smirnov Juri
Published: April 2024

The minimum testable dark matter (DM) mass for almost all DM signatures in celestial bodies is determined by the rate at which DM evaporates. DM evaporation has previously been calculated assuming a competition between the gravitational potential of the object, and thermal kicks from the celestial-body matter. We point out a new effect, where mediators with a range larger than the interparticle spacing induce a force proportional to the density gradient of celestial objects, forming an evaporation barrier for the DM. This effect can be so significant that evaporation does not occur even for sub-MeV DM, in stark contrast to previous calculations. This opens up a wide range of new light DM searches, many orders of magnitude in DM mass below the sensitivity of direct detection.
Control of quantum paths in harmonic generation through orthogonal fields specific frequency ratios
Authors: Wang Junjie , Xu Hongye , Ge Xinlei
Published: April 2024

By solving a two-dimensional, time-dependent Schrödinger equation, we investigate high-order harmonic generation for the

H
2
+

molecular ion in orthogonally polarized two-color laser pulses. We find that harmonic generation depends on the frequency ratio

n
=

ω
y

ω
x

. When the wavelength is 800 nm and n = 1.2, the harmonic plateau becomes smoother, and the quantum orbital interference decreases. We change the fundamental wavelength and find that the harmonic spectrum exhibits a supercontinuum structure, and the quantum orbital is controllable. When the wavelength is 1600 nm and 2000 nm, and n = 1.2, we gain a deeper understanding of the physical process of harmonics. We have provided the time-frequency distribution and the probability density of an electron wave packet picture. Next, we analyzed the impact of the carrier-envelope phase on harmonics, and we combined Lissajous figures to continue our analysis. The research results find that when the carrier-envelope phase is 0, 0.5π, π, and 1.5π, the harmonic intensity becomes higher, and all exhibit a supercontinuum structure. We chose certain orders of harmonics, and isolated attosecond pulses can be synthesized.
Noise-like pulse generation by amplified well-defined pulse in an optical fiber with negative group velocity dispersion
Authors: Chang Kuan-Yuan , Liu Jia-Ming
Published: April 2024

We experimentally and numerically demonstrate that noise-like pulses (NLPs) can be generated by pumping well-defined pulses (WDPs) into an optical fiber amplifier at a wavelength in the region of negative group velocity dispersion. Through investigating the evolution of the optical pulses, it is realized that the output pulses consist of NLPs at the pump wavelength and split solitons at Stokes wavelengths, due to intrapulse Raman scattering followed by the process of soliton fission. Such process of pulse breakup results in the generation of sub-pulses that have peak powers much higher than the unbroken WDPs have, enabling WDPs to strongly induce nonlinear effects. This finding resolves the discrepancy between the experiment and simulation results of supercontinuum generation by using picosecond WDPs in previous research.
Astronomical Knowledge Entity Extraction in Astrophysics Journal Articles via Large Language Models
Authors: Shao Wujun , Zhang Rui , Ji Pengli , Fan Dongwei , Hu Yaohua , Yan Xiaoran , Cui Chenzhou , Tao Yihan , Mi Linying , Chen Lang
Published: April 2024

Astronomical knowledge entities, such as celestial object identifiers, are crucial for literature retrieval and knowledge graph construction, and other research and applications in the field of astronomy. Traditional methods of extracting knowledge entities from texts face numerous challenging obstacles that are difficult to overcome. Consequently, there is a pressing need for improved methods to efficiently extract them. This study explores the potential of pre-trained Large Language Models (LLMs) to perform astronomical knowledge entity extraction (KEE) task from astrophysical journal articles using prompts. We propose a prompting strategy called Prompt-KEE, which includes five prompt elements, and design eight combination prompts based on them. We select four representative LLMs (Llama-2-70B, GPT-3.5, GPT-4, and Claude 2) and attempt to extract the most typical astronomical knowledge entities, celestial object identifiers and telescope names, from astronomical journal articles using these eight combination prompts. To accommodate their token limitations, we construct two data sets: the full texts and paragraph collections of 30 articles. Leveraging the eight prompts, we test on full texts with GPT-4 and Claude 2, on paragraph collections with all LLMs. The experimental results demonstrate that pre-trained LLMs show significant potential in performing KEE tasks, but their performance varies on the two data sets. Furthermore, we analyze some important factors that influence the performance of LLMs in entity extraction and provide insights for future KEE tasks in astrophysical articles using LLMs. Finally, compared to other methods of KEE, LLMs exhibit strong competitiveness in multiple aspects.
Research on spatiotemporal patterns of ground deformation caused by shallow buried tunnel construction in urban areas based on three-dimensional numerical simulation
Authors: Wang Jiande , Liang Zhu , Lin Lujie , Wu Zihao
Published: April 2024

According to incomplete statistics, since 2018, there have been as many as 15 geological safety accidents caused by urban subway construction in Guangzhou, resulting in significant loss of people’s lives and property and social impact. The main reason for this is insufficient research on the spatiotemporal patterns of ground deformation caused by shallow buried and underground excavation tunnel construction in complex disaster-prone environments and a lack of targeted geological risk prevention measures. This study combines various methods such as statistical analysis, on-site investigation and monitoring, and numerical simulation to reveal the spatiotemporal deformation laws of the ground caused by the construction of shallow buried and underground tunnels in cities. The results obtained can provide a reference for reducing or preventing ground accidents caused by urban subway construction, thereby better ensuring the safety of people’s lives and property.
Numerical Simulation of Deterioration Process in Reinforced Concrete Based on COMSOL Multiphysics
Authors: Li Gen , Wang Chenggong , Jiang Minghui , Li Lin , Wang Ruiqi
Published: April 2024

Reinforced concrete is deteriorated by chloride attack and dry-wet cycles to suffer serious durability problems. Reinforced concrete degradation typically occurs in two distinct stages: initially through chloride erosion, followed by the electrochemical corrosion of rebars. In this research, COMSOL Multiphysics was employed to model how various crack widths impact the degradation of reinforced concrete. Findings indicated that the deterioration process of reinforced concrete could be better simulated by COMSOL Multiphysics, and the degradation of reinforced concrete was significantly influenced by crack widths. As crack widths widen, chloride diffusion accelerated, leading to a rise in the corrosion current density of rebars. Notably, a crack width increased from 0.1 mm to 0.4 mm resulted in a 227.53% higher corrosion current density in rebars after 150 days of exposure. This study provides a theoretical basis for predicting reinforced concrete deterioration in the future.
Lateral strength evaluation of innovative and traditional composite shear wall systems
Authors: Li Yikang , Chen Zhihua , Zhou Junlong , Liu Xiaomin , Zhang Qian , Zhao Yun , Zhang Yang , Tian Buyuan , Gao Ruiqi
Published: April 2024

This paper proposes formulations for predicting lateral load-bearing capacity of two types of composite shear wall (CSW) systems, which consist of a steel frame and a reinforced concrete (RC) plate attached to one side using bolts. Due to the high out-of-plane stiffness of the RC plate, it can effectively provide out-of-plane constraint to prevent out-of-plane deformation of the steel plate in CSW systems. However, in traditional CSW systems, direct contact between the RC plate and the frame often results in crushing at the former under seismic loading, thereby providing insufficient restraint against out-of-plane deformation of the steel plate. In contrast, the innovative CSW system with a gap maintained at the steel frame and RC plate exhibited superior seismic behavior than its traditional counterpart. While previous studies have investigated cyclic behavior and parameter effects of CSW systems, there remains a gap in evaluating their lateral strength. The proposed formulations show a mean distinction among theoretically determined and actual lateral load-bearing capacity less than three percent.
Study on Mechanical Properties of QH-E Lunar Soil Simulant under Conventional Triaxial and Cyclic Triaxial Tests
Authors: Li Yunli , Li Jiawei , Yang Zhenrui , Wu Wenping
Published: April 2024

Study of the mechanical properties of lunar soil simulant is the key to conducting lunar soil sampling and lunar base construction. In this paper, conventional and cyclic triaxial tests are performed by using discrete element method (DEM) to study the mechanical properties of QH-E lunar soil simulant. The results indicate that the confining pressure has an important impact on the shear strength and dynamic modulus of QH-E lunar soil simulant. In the conventional triaxial test, with the increasing of the confining pressure, both the peak deviatoric stress and residual stress increase, and the relevant results have been supported by experiments. In cyclic triaxial test, the area of cyclic hysteresis loop decreases with the increasing of the number of cycles, the axial strain and dynamic modulus first increase and then tend to be stable with the increasing of the number of cycles. Moreover, the axial strain increases with increasing confining pressure, while dynamic modulus decreases at a specific cyclic stress ratio (CSR) condition.
Research On Soil Displacement Prediction Method Caused By High-pressure Jet Grouting Pile Group Construction Under Adjacent Pile Response
Authors: Hu Junjie , Zhao Wenhui , Wang Baocheng , Zhang Ke
Published: April 2024

This paper analyzes the soil displacement effect during high-pressure jet grouting pile construction by simplifying the construction process as a series of pressure-controlled spherical cavity expansions in a semi-infinite soil medium. Based on the elastic-plastic solution of pressure-controlled spherical cavity expansion theory, a calculation method is proposed to estimate the soil displacement caused by high-pressure jet grouting pile construction. Non-linear contact theory between the pile and soil is introduced, and the finite difference method is employed to determine the internal forces and deformations of the pile. The proposed method is applied to field construction cases, and its validity is verified by comparing the results with on-site monitoring data. The research findings reveal that the soil displacement effect decreases with depth and primarily occurs in shallow soil layers during the construction of individual high-pressure jet grouting piles. The lateral displacement at the ground surface increases first and then decreases with the increase in horizontal distance, while the ground uplift exhibits an exponential decay trend.
Simulation Study of Electromagnetic Standing Wave Method for Pre-stress Detection of Steel Strands
Authors: Zheng Boren , Mu Zhixing
Published: April 2024

With the widespread application of pre-stressed technology, effective pre-stress monitoring has become a key research area in the field of health monitoring, such as bridges. This paper conducts a simulation-based validation study based on the electromagnetic standing wave pre-stress measurement method. Through the analysis of the implementation process and principles of the electromagnetic standing wave measurement method, frequency domain simulations are performed in HFSS software, and then the frequency domain results are imported into ADS for time domain simulations, ultimately verifying the feasibility of the electromagnetic standing wave pre-stress measurement method. Experimental results indicate that the electromagnetic standing wave method can achieve non-destructive and effective monitoring of in-service pre-stressed steel strands.
Research on Strain of Unequal Wall Thickness Pipeline of the X80 Pipeline under Lateral Load
Authors: Wen Qing , Zhang Wenjuan , Qiu Yanhua
Published: April 2024

X80 steel is a material with high strength and good toughness, which is widely used in long-distance natural gas pipelines. Pipelines will have different wall thicknesses, depending on the safety level requirements of different regions. Two sections of pipes with different wall thickness form unequal wall thickness of pipeline (UWTP) that is joined together by welding. UWTP pass through some geohazard areas, such as landslides. The frequency of landslides is extremely high in mountainous areas, which can seriously affect the safe operation of UWTP. In this paper, a model of a 12.8 mm wall pipe section and a 15.6 mm wall pipe section are linked by girth welds. The strain between the pipe section and the weld was quantitatively analyzed. The results show that the strain at the girth weld in the 3 o’clock direction of the pipe increases sharply. The strain in the 9 o’clock direction of the pipe is generally lower than the strain in the 3 o’clock direction. The strain value of the 12.8mm wall thickness pipe section is generally greater than the strain value of the 15.6mm wall thickness pipe section.
Application and Research of Distributed Acoustic Sensing in Vibration Monitoring of Subway Tunnels
Authors: Gao Jian , Wang Min , Yang Fan , Wan Lijun , Zhang Kaikun , Sang Weibing , Duan Wei , Li Dongming
Published: April 2024

With the booming development of the rail transit industry and the increase in the construction and operation of mileage, the health status of infrastructure such as vehicles, tracks, and trains, as well as operational safety, have received widespread attention. Distributed optical fiber sensing technology has the characteristics of long monitoring distance, strong real-time performance, and highly economical, and has broad prospects in rail transit applications. This paper adopts Distributed Acoustic Sensing technology to obtain vibration information along the subway tunnel, analyzes the time-domain signal and frequency-domain energy characteristics of train vibration, as well as the passing time, direction, and location of the train, providing technical support for the safe operation of the subway.
Nanopore arrays with TMOKE-enhanced high performance sensing
Authors: Lei Fugui , Li Lixia , Li Penglei , Liu Yufang
Published: April 2024

Magneto-plasmon sensing structure based on surface plasmon resonance (SPR) and magneto-optical (MO) effect has become a hot research topic in recent years. In this work, we propose a magneto-plasmon crystal consisting of an Au/Co double-layer nanoporous structure with optically thick Au film as a substrate. Due to the excitation of high-quality SPR, a Fano-like transverse magneto-optical Kerr (TMOKE) spectrum with subnanometer bandwidth is realized. A sensitivity of up to 677 nm RIU−1 is detected under subtle refractive index changes in air, and all the calculated figure of merits (FOM) are higher than 104 RIU−1. In addition, in order to highlight the superiority of the sensing performance of the MO plasmon (MOSPR) sensor, we compare the MOSPR sensor with the SPR sensor and calculate their FOM in different refractive index environments. The results show that the FOM of the MOSPR sensor is two orders of magnitude higher than that of the SPR sensor, which proves that the performance of the MOSPR sensor is significantly better than that of the SPR sensor and provides a theoretical basis for biosensing and gas detection based on magneto plasmon.
Large-aperture imaging system based on 100 mm all-Si metalens in long-wave infrared
Authors: Li Aoling , Duan Huigao , Jia Honghui , Long Lichao , Li Jianhua , Hu Yueqiang
Published: April 2024

Metalens, which composed of micro-nano structures at sub-wavelength scale, possessing the ability to achieve the functions of traditional lens elements, paving the way for the development of lightweight and integrated imaging systems. Nowadays, the majority of research efforts in the field of metalens have been concentrated on the exploitation of short optical wavelength band with tiny apertures. Here, we have directed our focus towards the long-wave infrared (LWIR) band, which holds significant importance for crucial applications like infrared imaging and detection. We have prepared a metalens with a remarkable aperture of 100 mm and a high numerical aperture of 0.89 at an operating wavelength of 9.35 μm, which is currently the largest reported aperture in LWIR with high light harvesting capability. And the imaging performance was verified by demonstrating the imaging results of the metalens on targets with different temperatures through thermal imaging tests.
Comparison of weighting algorithms to mitigate respiratory motion in free-breathing neonatal pulmonary radial UTE-MRI
Authors: Gandhi Deep B , Higano Nara S , Hahn Andrew D , Gunatilaka Chamindu C , Torres Luis A , Fain Sean B , Woods Jason C , Bates Alister J
Published: April 2024

Background. Thoracoabdominal MRI is limited by respiratory motion, especially in populations who cannot perform breath-holds. One approach for reducing motion blurring in radially-acquired MRI is respiratory gating. Straightforward ‘hard-gating’ uses only data from a specified respiratory window and suffers from reduced SNR. Proposed ‘soft-gating’ reconstructions may improve scan efficiency but reduce motion correction by incorporating data with nonzero weight acquired outside the specified window. However, previous studies report conflicting benefits, and importantly the choice of soft-gated weighting algorithm and effect on image quality has not previously been explored. The purpose of this study is to map how variable soft-gated weighting functions and parameters affect signal and motion blurring in respiratory-gated reconstructions of radial lung MRI, using neonates as a model population. Methods. Ten neonatal inpatients with respiratory abnormalities were imaged using a 1.5 T neonatal-sized scanner and 3D radial ultrashort echo-time (UTE) sequence. Images were reconstructed using ungated, hard-gated, and several soft-gating weighting algorithms (exponential, sigmoid, inverse, and linear weighting decay outside the period of interest), with %Nproj representing the relative amount of data included. The apparent SNR (aSNR) and motion blurring (measured by the maximum derivative of image intensity at the diaphragm, MDD) were compared between reconstructions. Results. Soft-gating functions produced higher aSNR and lower MDD than hard-gated images using equivalent %Nproj, as expected. aSNR was not identical between different gating schemes for given %Nproj. While aSNR was approximately linear with %Nproj for each algorithm, MDD performance diverged between functions as %Nproj decreased. Algorithm performance was relatively consistent between subjects, except in images with high noise. Conclusion. The algorithm selection for soft-gating has a notable effect on image quality of respiratory-gated MRI; the timing of included data across the respiratory phase, and not simply the amount of data, plays an important role in aSNR. The specific soft-gating function and parameters should be considered for a given imaging application’s requirements of signal and sharpness.
A novel SPM error measurement method based on peak detection of nodes centers in a 2D orthogonal lattice as standard
Authors: Chen Xiaomei , Wan Yu
Published: April 2024

This paper presented a novel scanning probe microscope (SPM) error measurement method by using a 2D micro-scale orthogonal lattice standard and peak detection (PD) method of the pitch center coordinates based on cross-correlation/convolution (CC) filtering of images raster-scanned by SPMs. The geometric errors of motion and drifting rate in x-y plane are measured. Geometric errors include positional deviations

E
x
x

and

E
y
y
,

straightness deviations

E
x
y

and

E
y
x

along x- and y-axis respectively, and the orthogonality deviation

E
o
x
y

between the two axes. The calibration factors

C
x

and

C
y

were calculated based on the number of pixels scanned on the x-axis and y-axis, scanning range, average pitch of standard lattice from metrological verification certification, and average lattice pitch calculated by using PD method. Through case study, the errors of an AFM was measured using an orthogonal lattice standard with a nominal pitch of 10 μm, resulting in

C
x

and

C
y

values of 0.925 and 1.050, respectively, an orthogonal deviation

E
o
x
y

of 0.015°, and the maximum drift rate of the x-axis and y-axis is −366.21 nm min−1 and −317.38 nm min−1, respectively. The new error measurement method of SPMs provides technical reference for the development and performance improvement of SPM instruments.
A novel heap-based optimizer for allocation of shunt capacitors in radial distribution network
Authors: Adebayo Isaiah , Salimon Sunday , Adejumo Joshua , Yussuf Adedayo , Aborisade David
Published: April 2024

Due to power losses, a sizeable portion of the electrical power produced is lost, which causes voltage deviation and instability as a result of rising load demand at the radial distribution network (RDN). Shunt capacitor penetration will enhance the RDN’s efficiency by reducing power losses, improving the voltage profile and stability. For the best sizing and allocation of shunt capacitors (SCs) in RDN, a novel human-based metaheuristic heap-based optimizer (HBO) influenced by the ideas of corporate rank hierarchy (CRH) of standard organization is presented. The real power loss, voltage variation, and voltage stability index are all minimized while equality and inequality criteria are met by the HBO optimal allocation of SCs. One, two, and three numbers of SCs were investigated when installing the reactive compensating devices. Using typical IEEE 33-bus and 69-bus RDNs, covering a range of scenarios in the form of single- and multi-objective functions, the effectiveness of the HBO technique was examined. The real power loss for the conventional IEEE 33-bus and 69-bus RDN was reduced by 34.46% and 35.50%, respectively compared to their respective base cases. By contrasting the outcomes of the power loss with well-established and new optimization approaches, the efficacy and superiority of the suggested HBO were demonstrated.
Conditional proof of the ergodic conjecture for falling ball systems
Authors: Simanyi Nandor
Published: April 2024

In this paper we present a conditional proof of Wojtkowski’s ergodicity conjecture for the system of

1
D

1D

perfectly elastic balls falling down in a half line under constant gravitational acceleration, [Ergodic Theory Dynam. Systems 5 (1985), no. 1, 145–161], [Comm. Math. Phys. 105 (1986), no. 3, 391–414], [Comm. Math. Phys. 126 (1990), no. 3, 507–533], [Comm. Math. Phys. 127 (1990), no. 2, 425–432], [Fund. Math. 157 (1998), no. 2-3, 305–341]. Namely, we prove that almost every such system is (completely hyperbolic and) ergodic, by assuming the transversality between different singularities and between singularities and stable (unstable) invariant manifolds. This transversality condition will be removed in the author’s upcoming paper Simanyi, Preprint, (2023).
Fractal functions using weak contraction theory in some function spaces and generalized 𝛼-fractal functions
Authors: Verma Manuj , Priyadarshi Amit
Published: April 2024

In this paper, we demonstrate the existence of a new class of fractal functions in standard function spaces such as the Lebesgue function space and the bounded function space. We also provide the existence of the general version of the so-called ‘

α
\alpha

-fractal function’. We emphasize the fact that our construction provides some new classes of fractal functions that are not obtained by the previously known classes of

α
\alpha

-fractal functions. We also discuss the stability and the fractal dimension of the newly constructed fractal functions. Lastly, we plot approximate graphs of some newly constructed fractal functions.
Leaf topology of minimal hyperbolic foliations with non simply-connected generic leaf
Authors: Gusmão Paulo , Meniño Cotón Carlos
Published: April 2024

A noncompact (oriented) surface satisfies the condition

(
⋆
)

(\star )

if their isolated ends are accumulated by genus. We show that every surface satisfying this condition is homeomorphic to the leaf of a minimal codimension one foliation on a closed

3
3

-manifold whose generic leaf is not simply connected. Moreover, the above result is also true for any prescription of a countable family of noncompact surfaces (satisfying

(
⋆
)

(\star )

): they can coexist in the same minimal codimension one foliation as above. All the given examples are hyperbolic foliations, meaning that they admit a leafwise Riemannian metric of constant negative curvature.
Predictors of clinical outcome in myeloproliferative neoplasm, unclassifiable: A Bone Marrow Pathology Group study
Authors: Crane Genevieve M , Geyer Julia T , Thakral Beenu , Wang Sa A , Wool Geoffrey D , Li Ke David , Davis Adam R , Boiocchi Leonardo , Bosler David , Bueso-Ramos Carlos E , Arber Daniel A , George Tracy I , Bagg Adam , Hasserjian Robert P , Orazi Attilio , Hsi Eric D , Rogers Heesun J
Published: April 2024

Objectives

Myeloproliferative neoplasm, unclassifiable (MPN-U, revised to MPN, not otherwise specified in the fifth edition of the World Health Organization classification) is a heterogeneous category of primary marrow disorders with clinical, morphologic, and/or molecular features that preclude classification as a more specific MPN subtype due to stage at diagnosis, overlapping features between MPN subtypes, or the presence of coexisting disorders. Compared with other MPN subtypes, the contribution of the mutational landscape in MPN-U in conjunction with other clinical and morphologic biomarkers to prognosis has been less well investigated.

Methods

We performed a multicenter, retrospective study of MPN-U (94 cases) to better define the clinicopathologic features, genetic landscape, and clinical outcomes, including subgroups of early-stage, advanced-stage, and coexisting disorders. The Dynamic International Prognostic Scoring System (DIPSS) plus scoring system was applied to assess its relevance to MPN-U prognosis.

Results

Multivariate analysis demonstrated bone marrow blast count and DIPSS plus score as statistically significant in predicting overall survival. Univariate analysis identified additional potential poor prognostic markers, including abnormal karyotype and absence of JAK2 mutation. Secondary mutations were frequent in the subset analyzed by next-generation sequencing (26/37 cases, 70.3%) with a borderline association between high molecular risk mutations and overall survival.

Conclusions

This study, as one of the largest of MPN-U studies incorporating both clinicopathologic and molecular data, moves toward identification of biomarkers that better predict prognosis in this heterogeneous category.