bluuebunny/crossref_metadata_2025 huggingface dataset:
Association of Cardiovascular Health with the Incidence of Venous Thromboembolism: A Prospective Study of 275,149 Participants from the UK Biobank
Authors: Liang Benhui , Zha Lihuang , Peng Baohua , Chen Qin , Juaiti Mukamengjiang , Zeng Xiaofang , Feng Yilu , Yu Zaixin , Tang Yiyang
Published: April 2024

Background The Life's Essential 8 (LE8) score, recently proposed by the American Heart Association, represents a new paradigm for evaluating cardiovascular health (CVH). We aimed to explore the association between CVH, estimated using LE8, and venous thromboembolism (VTE) incidence.

Methods A total of 275,149 participants were recruited from the UK Biobank and divided into high (LE8 score ≥ 80), moderate (LE8 score < 80 but ≥ 50), and low (LE8 score < 50) CVH groups. Restricted cubic spline analysis, the Kaplan–Meier method, and the Cox proportional hazards model were used to explore the association between CVH and VTE. The genetic predisposition to VTE was assessed with a polygenic risk score. Sensitivity analyses were performed to validate the results.

Results During a median follow-up of 12.56 years, VTE developed in 506 (4.09%), 6,069 (2.78%), and 720 (1.66%) participants with low, moderate, and high CVH levels, respectively. Compared with the low CVH group, participants in the moderate and high CVH groups had a 23% (hazard ratio [HR]: 0.77; 95% confidence interval [CI]: 0.71–0.85) and 41% (HR: 0.59; 95% CI: 0.52–0.66) lower risk of VTE, respectively, after adjusting for demographic characteristics, medical history, socioeconomic status, and genetic predisposition. This association remained robust in multiple sensitivity analyses. Higher CVH levels led to a more pronounced reduction in the risk of VTE in females and could appreciably offset the genetic risk of VTE.

Conclusion Higher CVH levels were significantly associated with a lower incidence of VTE, encouraging efforts to increase LE8 scores in individuals.
Topological insulators and K-theory
Authors: Kaufmann Ralph M. , Li Dan , Wehefritz–Kaufmann Birgit
Published: April 2024

We analyze topological invariants, in particular Z2 invariants, which characterize time reversal invariant topological insulators, in the framework of index theory and K-theory. After giving a careful study of the underlying geometry and K-theory, we formalize topological invariants as elements of KR theory. To be precise, the strong topological invariants lie in the higher KR groups of spheres; KR̃−j−1(SD+1,d). Here j is a KR-cycle index, as well as an index counting off the Altland-Zirnbauer classification of Time Reversal Symmetry (TRS) and Particle Hole Symmetry (PHS)—as we show. In this setting, the computation of the invariants can be seen as the evaluation of the natural pairing between KR-cycles and KR-classes. This fits with topological and analytical index computations as well as with Poincaré Duality and the Baum–Connes isomorphism for free Abelian groups. We provide an introduction starting from the basic objects of real, complex and quaternionic structures which are the mathematical objects corresponding to TRS and PHS. We furthermore detail the relevant bundles and K-theories (Real and Quaternionic) that lead to the classification as well as the topological setting for the base spaces.
Recent developments in wearable piezoelectric energy harvesters
Authors: Sun Lei , He Lipeng , Yu Gang , Zheng Xiaotian , Wang Hongxin , Yu Dahai , Lin Jieqiong
Published: April 2024

Wearable piezoelectric energy harvesters (WPEHs) have gained popularity and made significant development in recent decades. The harvester is logically built by the movement patterns of various portions of the human body to harvest the movement energy and immediately convert it into usable electrical energy. To directly power different microelectronic devices on the human body, a self-powered device that does not require an additional power supply is being created. This Review provides an in-depth review of WPEHs, explaining the fundamental concepts of piezoelectric technology and the materials employed in numerous widely used piezoelectric components. The harvesters are classed according to the movement characteristics of several portions of a person's body, such as pulses, joints, skin, and shoes (feet). Each technique is introduced, followed by extensive analysis. Some harvesters are compared, and the benefits and drawbacks of each technique are discussed. Finally, this Review presents future goals and objectives for WPEH improvement, and it will aid researchers in understanding WPEH to the point of more efficient wireless energy delivery to wearable electronic components.
Dynamic of binary molecular systems—Advantages and limitations of NMR relaxometry
Authors: Leal Auccaise Adriane Consuelo , Masiewicz Elzbieta , Kolodziejski Karol , Kruk Danuta
Published: April 2024

1H spin-lattice relaxation studies have been performed for binary systems, including glycerol as the first component and alanine, glycine, and aspartic acid (with different levels of deuteration) as the second one. The relaxation studies have been performed in the frequency range from 10 kHz to 10 MHz vs temperature. A theoretical framework, including all relevant 1H–1H and 1H–2H relaxation pathways, has been formulated. The theory has been exploited for a thorough interpretation of a large set of the experimental data. The importance of the 1H–2H relaxation contributions has been discussed, and the possibility of revealing dynamical properties of individual liquid components in binary liquids has been carefully investigated. As far as the dynamical properties of the specific binary liquids, chosen as an example, are considered, it has been shown that in the presence of the second component (alanine, glycine, and aspartic acid), both molecular fractions undergo dynamics similar to that of glycerol in bulk.
The role of epoxidation process on improving the oxidative, thermal stability, and tribological performance of mustard oil nano lubricants
Authors: Sikdar Soumya , Menezes Pradeep L.
Published: April 2024

This study investigated the potential of inedible mustard oil (MO) (Brassica juncea) as a suitable bio-lubricant for enhanced thermal, oxidative stability, and tribological performance. To improve the MO's oxidative stability, it was subjected to a chemical epoxidation reaction, forming epoxidized mustard oil (EMO). The MO and EMO were evaluated for viscosity, functional groups, wettability, oxidative stability, thermal stability, friction, and wear performance. The epoxidation process resulted in nearly doubling the oxidative stability, as well as improving the thermal stability of the MO. Results showed that the EMO exhibited better lubricating properties than the MO, including lower friction and wear. To further improve the lubrication performance of the EMO, solid lubricant additives (SLAs) were incorporated in various concentrations. These SLAs were graphene nanoplatelets (GNP) and hexagonal boron nitride (hBN). The GNP and hBN nano lubricants reduced friction by 31% and 13% compared to the EMO. The same nano lubricants also lowered wear by 73% and 51% relative to the EMO. The underlying mechanisms behind the improvement in the friction and wear performance were discussed. The EMO can be considered as a suitable base stock for renewable and sustainable energy applications.
Measurement of coating–substrate interface stiffness using a constructed ultrasonic echo phase derivative spectrum
Authors: Qi Tianzhi , Lin Li , Ma Zhiyuan , Yang Jiwei , Zhao Yang
Published: April 2024

Measurement of coating–substrate interface stiffness can indirectly characterize interface bonding quality. This paper proposes a noval quantitative inversion coating–substrate interface stiffness method based on the multi-resonance frequencies of a constructed ultrasonic echo phase derivative spectrum (UEPDS). The theoretical relationship between UEPDS resonance frequencies and interface stiffness is derived. The detection frequency and high-sensitivity interface stiffness range are optimized based on the sensitivity analyzed. Numerical simulation and experiment are implemented on a 0.48 mm aluminum layer/carbon steel substrate specimen to prove the validity of the proposed ultrasonic method. The simulation results show that the maximal relative error between the inversion and the preset interface stiffnesses is reduced from 23% to 8% compared with the traditional ultrasonic reflection coefficient amplitude spectrum-based (URCAS-based) method. The experiment results indicate that the UEPDS-based inversion interface stiffnesses have the same trend as the nominal contact pressures between the coating–substrate interface.
Time difference detection based on sliding window all-phase FFT and Kalman filtering for precise flow measurement
Authors: Jing Jiaqi , Zheng Dezhi , Fan Shangchun
Published: April 2024

Coriolis mass flowmeter (CMF) measures the mass flow rate by detecting the time difference, typically using frequency domain methods. However, the spectrum leakage is the primary challenge. To address this issue, a new time difference detection method is proposed utilizing sliding window and all-phase fast Fourier transform. The computational complexity is reduced considering the changes in signal frequency. To further improve the stability and response speed of the measured value, a Kalman filtering algorithm based on variance detection is also proposed for post-processing. A transmitter system is developed to validate the proposed methods. The results demonstrate that, for single phase fluids, the accuracy is better than 0.5‰ and the repeatability is better than 0.2‰, thereby offering an improvement in the accuracy of CMF and supporting for industrial applications.
Agrivoltaic system success: A review of parameters that matter
Authors: Ali Naseem
Published: April 2024

Solar energy is a rapidly growing sector, and agrivoltaic farms are playing an increasingly important role in meeting the world's energy needs. However, as the size and complexity of these farms increase, so do the challenges associated with managing them efficiently. This article presents a comprehensive review of the fundamental parameters that underpin agrivoltaic systems. Focusing on the latest research, this review examines the challenges and opportunities intrinsic to the implementation of agrivoltaic energy systems, paying particular attention to the various parameters that contribute to their performance. These parameters encompass a range of factors such as heat islands, shading factors, and surface energy budget. The review underscores the importance of considering a diverse array of parameters when developing agrivoltaic energy systems to optimize their efficiency and effectiveness.
Dynamic response characteristics of water–gas–coal in freezing process of gas-bearing coal under water infiltration condition
Authors: Yue Jiwei , Xu Jinlin , Sun Yongxin , Shi Biming , Wang Qiao , Wang Long , Wang Chen
Published: April 2024

Rock cross-cut coal uncovering (RCCU) is susceptible to coal and gas outburst incidents, greatly impeding the safe extraction and miner safety. Freezing coal at low temperatures can enhance its mechanical properties and encourage gas adsorption. For the practical application of this method to prevent coal and gas outburst, water needs to be injected into the coal seam. However, the mutual dynamic response of the water–gas–coal combination during low-temperature freezing has not been sufficiently investigated, seriously restricting its application in disaster prevention. Therefore, this study investigates these characteristics using a low-temperature freezing experimental setup that was built for gas-bearing coal under conditions of water infiltration. The findings indicated that under low-gas-pressure conditions, the coal samples exhibited a larger degree of pore wettability. The improved Aronofsky index model was used to explain the relationship between the gas replacement quantity and time. Time required for the coal temperature to reach equilibrium showed a positive correlation with freezing temperature and gas pressure, respectively. As freezing temperature and gas pressure rise, respectively, freezing coal's thermal conductivity falls. The longitudinal strain of freezing coal rises with the drop in gas pressure and freezing temperature, respectively. Low-temperature freezing was conducive to the transformation of micropores and small pores into mesopores, macropores, and fractures. Based on these results, a collaborative measure of borehole methane drainage, coal seam water injection, and low freezing coal to prevent coal and gas outburst was proposed. The study lays a theoretical foundation for preventing coal and gas outbursts during RCCU.
Swift heavy ion irradiation-driven energy band engineering and its profound influence on the photoresponse of β-Ga2O3 ultraviolet photodetectors
Authors: Zhu Huiping , Tang Yuanjun , Zhong Aoxue , Wang Lei , Liu Fanyu , Zhao Peixiong , Liu Jie , Shu Lei , Wu Zhenping , Li Bo
Published: April 2024

Swift heavy Ta ions with an ultra-high energy of 2896 MeV are utilized for irradiation of β-Ga2O3 photodetectors. Noteworthy variations in device performance under different wavelengths are observed. Under 254 nm light illumination, the photocurrent of the devices exhibit degradation at low ion fluences but gradually recover and even surpass the performance of non-irradiated devices at the irradiation fluence of 1 × 1010 cm−2. Conversely, under 365 nm light illumination, photocurrent increases at low fluence but slightly decreases at the same high fluence of 1 × 1010 cm−2. Cathodoluminescence spectra and first-principles calculations elucidate the mechanism underlying the evolution of device performance with irradiation fluence. At low irradiation fluence, the introduction of point defects such as oxygen vacancies and gallium vacancies leads to an expansion of the bandgap, resulting in a decline in photocurrent under 254 nm light illumination. Additionally, deep defect levels are generated by these point defects, promoting an enhancement of photocurrent under 365 nm light illumination. Higher fluences transform these point defects into complex defects such as Ga–O pair vacancies, resulting in a reduction in the bandgap. Consequently, an increase in photocurrent is observed for devices illuminated with 254 nm light. However, at high irradiation fluences, charge recombination induced by the presence of deep defect levels becomes more significant, leading to a decrease in photocurrent when exposed to 365 nm light. No matter what, at 1 × 1010 cm−2 fluence, β-Ga2O3 photodetectors still maintain excellent performance, implying their strong radiation resistance and immense potential for application in space environments.
Cosmic tau neutrinos uncovered
Authors: Grant Andrew
Published: April 2024

An image-scouring AI model assists researchers in finding signatures of the most elusive variety of neutrino.
Posttranscriptional regulation of
FAN1
by miR-124-3p at rs3512 underlies onset-delaying genetic modification in Huntington’s disease
Authors: Kim Kyung-Hee , Hong Eun Pyo , Lee Yukyeong , McLean Zachariah L. , Elezi Emanuela , Lee Ramee , Kwak Seung , McAllister Branduff , Massey Thomas H. , Lobanov Sergey , Holmans Peter , Orth Michael , Ciosi Marc , Monckton Darren G. , Long Jeffrey D. , Lucente Diane , Wheeler Vanessa C. , MacDonald Marcy E. , Gusella James F. , Lee Jong-Min
Published: April 2024

Many Mendelian disorders, such as Huntington’s disease (HD) and spinocerebellar ataxias, arise from expansions of CAG trinucleotide repeats. Despite the clear genetic causes, additional genetic factors may influence the rate of those monogenic disorders. Notably, genome-wide association studies discovered somewhat expected modifiers, particularly mismatch repair genes involved in the CAG repeat instability, impacting age at onset of HD. Strikingly,
FAN1
, previously unrelated to repeat instability, produced the strongest HD modification signals. Diverse
FAN1
haplotypes independently modify HD, with rare genetic variants diminishing DNA binding or nuclease activity of the FAN1 protein, hastening HD onset. However, the mechanism behind the frequent and the most significant onset-delaying
FAN1
haplotype lacking missense variations has remained elusive. Here, we illustrated that a microRNA acting on 3′-UTR (untranslated region) SNP rs3512, rather than transcriptional regulation, is responsible for the significant
FAN1
expression quantitative trait loci signal and allelic imbalance in
FAN1
messenger ribonucleic acid (mRNA), accounting for the most significant and frequent onset-delaying modifier haplotype in HD. Specifically, miR-124-3p selectively targets the reference allele at rs3512, diminishing the stability of
FAN1
mRNA harboring that allele and consequently reducing its levels. Subsequent validation analyses, including the use of antagomir and 3′-UTR reporter vectors with swapped alleles, confirmed the specificity of miR-124-3p at rs3512. Together, these findings indicate that the alternative allele at rs3512 renders the
FAN1
mRNA less susceptible to miR-124-3p-mediated posttranscriptional regulation, resulting in increased FAN1 levels and a subsequent delay in HD onset by mitigating CAG repeat instability.
The bee and the flower
Authors: Chatterjee Ariktam
Published: April 2024

This chapter is an attempt to understand human translation of cultural texts generated through human agency as a
structural continuation of biotranslation prevalent in the natural world. It begins by analysing bee communication and orchid
mimicry as examples of biotranslation located within the tripartite biosemiotic model of Carlo Brentari, following Jakob von
Uexküll, and finally arrives at a method in translation studies that prioritises cooperative engagements through an inclusive
theory of semiotic hospitality. For this, the model of the Samavasarana from Jain philosophy is applied, both because of its
ecological expanse, and its structural affinity to Brentari’s biosemiotic model. Concluding Kierkegaard’s temporal realm of
human concerns to be the reason for functional cleavage between the semiosphere from the biosphere, resetting that connection
is the purpose of this article.
Translation and biosemiotics
Authors: Baer Brian James
Published: April 2024

The emergence of biosemiotics in Soviet translatology and related fields has a unique history, which is related to
the adoption and adaptation of Saussurean linguistics to various fields, beginning with literature. This chapter traces this
trajectory in two distinct periods. The first period covers the initial adoption of formalist concepts by translation
scholars, such as Dmitrii Usov and Andrei Fodorov, in the late 1920s and early 1930s. The second period relates to the
rediscovery of Russian formalism in the post-World War II period, and its role in the evolution of the concept of translation
among the scholars of the Moscow-Tartu Semiotic School, focusing on the writings of Juri Lotman.
The complex time of signs
Authors: Atã Pedro
Published: April 2024

Semiosis develops under the conditions of semiotic complexity. Translation directly addresses such conditions, like
non-linearity, perspective pluralism, emergence, material diversity. In this work, I suggest that the complexity of sign
processes is related to their time. I make use of C. S. Peirce’s theory of categories and process philosophy, to suggest that
the complex nature of sign action is related to the way the time of signs is multilayered. In this framework, translation can
be conceptualised as a temporal operation that redistributes the time of signs so that source signs habitually recur in target
signs. This approach suggests a focus on the irreducible gaps in the time of signs, such as in situations of surprise, or
break of habit.
Assessing the impact of climate action mitigation strategies from livestock production: A review – Solution for greenhouse gases mitigation
Authors: Terefe Geberemariyam , Walelegne Mulugeta
Published: April 2024

The main sources of greenhouse gas (GHG) emissions are enteric fermentation from ruminants and manure management. An integrated strategy-combination approach incorporating nutrition and manure management is necessary to dramatically reduce GHGs and the carbon footprint of milk production. The aim of this review was to assess the effect of climate action mitigation strategies on the GHG production of ruminant animals. This review was based on the different references, which are textbooks, journals, proceedings, conferences, and abstracts accessed through Agricola, Agris, CAB Abstracts, Embase, MEDLINE, and the Web of Science. The research findings were done by using dairy cattle, sheep, and goat; the numbers of animals used in each experiment were given the majority of attention, and decisions were also made based on the method used to quantify methane (CH
4
) and nitrous oxide. Enteric CH
4
per unit of milk was reduced by 6–8% when higher-starch corn silage was used in place of barley or alfalfa silage. Cows fed seaweed (1.77–2%, on dry matter [DM] basis) experienced a linear drop in enteric CH
4
emission from 383 to 400 g/d. Supplementation of vegetable fats (6%) and coconut oil (12 g/day) to ruminant diets can decrease CH
4
emissions by 21–40% and 50–61.2%, respectively. Similarly, the addition of 21.5 g nitrate/kg DM reduces CH
4
yield (17%) in sheep. Bovaer can reduce methane emissions (30%) for dairy cows. Feed processing and additives are alternative strategies to minimize GHG production in ruminants, but further studies on additives and their residual effect on livestock output is needed.
When Dogs Talk: Technologically Mediated Human-Dog Interactions as Semiotic Assemblages
Authors: Lind Miriam
Published: April 2024

Pets using “talking buttons” to ostensibly tell their owner about their thoughts and needs have become a huge success on social media. With buttons that upon activation play a prerecorded message, these devices are marketed as tools in teaching human language to animals in order to allow them to “speak their minds.” This article investigates these practices of technologically mediated human-dog interactions through the analysis of social media videos and examines the claim that these button-based interactions are illustrative of animals’ language acquisition. This article concludes that “talking buttons” in human-dog communication should rather be understood as semiotic assemblages in which meaning is collaboratively constructed through the dynamic, situated interaction of bodies, linguistic resources, objects, and touch.
Voices, Bodies, and the Cultural Organization of Meaning
Authors: Levon Erez , Holmes-Elliott Sophie
Published: April 2024

This article examines how the “arbitrary content of culture” (Bourdieu 1977) comes to be inscribed onto patterns of sociolinguistic variation. Specifically, we consider the role of iconicity in this process. Studies of iconicity and variation to date have tended to focus on the iconic properties of the speech signal itself (e.g., an association between higher-frequency sounds and smallness). We bring these ideas about sound symbolism into dialogue with research on embodied behavioral codes, which link particular forms of bodily comportment and their associated qualia with specific social categories and positions. We suggest that certain claims about sound symbolic meanings may be better interpreted as derived effects of socially meaningful bodily hexis. Our arguments are illustrated through a consideration of two variables, both of which have received widespread attention in the literature on variation in English: the backing and lowering of the short front vowels and the fronting/backing of /s/. We discuss how treating these variables from the perspective of socially inculcated bodies can provide a unified account of their observed sociolinguistic patterning and help to shed light on how variables accrue social meaning more generally.
More Than Signs: International Sign as Distributed Practice
Authors: Kusters Annelies
Published: April 2024

This article makes a case for understanding International Sign (IS) as a distributed practice. IS, a translingual practice, arose from interactions among individuals from diverse linguistic backgrounds, integrating signs from multiple national sign languages and leveraging iconic and transparent features of sign language lexicons and grammars. At the heart of IS is the principle of calibration, an adaptive process aimed at aligning signs to foster mutual understanding. This study delves into the use of IS in an adult education classroom in Denmark, where IS includes not only the use of signs but also their interplay with technology and writing. The discussed examples suggest that IS is a fluid process in which people shift between conventional and adaptive signing. Furthermore, the examples showcase an intricate relationship between signing and forms of writing, suggesting that the latter should not be seen as separate from IS.
Inverse design of two-function transmission-type reconfigurable polarization control metasurfaces based on deep learning
Authors: Hu Yanwen , Ma Yaodong , Zhou Wenying , Zhang Tingrong , Chen Qingyang
Published: April 2024

Compared with single-function metasurfaces, the design difficulty of multi-function metasurfaces increases significantly. This paper introduces an inverse design method based on deep learning to address this challenge. By this method, a transmission-type reconfigurable polarization control metasurface (TRPCM) with two functions is rapidly designed. The network model used in the method consists of an electromagnetic parameter reconstruction network model and an inverse prediction network model. The combination of the two models can solve the problem of difficulty in defining high-dimensional inputs in traditional inverse design, and achieve accurate prediction of metasurface structure parameters under given design targets. To optimize the hyperparameters of the neural network model, a genetic algorithm was introduced. To solve the non-uniqueness problem of inverse design, a method for eliminating similar data by calculating Euclidean Distance was introduced. Both schemes further improve the predictive performance of the proposed network model. Finally, six design targets were set based on the TRPCM. The structural parameters of the metasurface were successfully predicted using two neural network models and achieved the required performance. On this basis, a set of parameters was selected for experimental validation. By controlling the ON or OFF of the PIN diodes, the fabricated metasurface achieves two functions: linear-to-circular polarization conversion and linear polarization maintenance in the range of 2–3.6 GHz. Study results show that the inverse design scheme proposed in the paper is feasible and practical for solving the rapid optimization design of complex multi-function metasurfaces.
High figure-of-merit A1-mode lamb wave resonators operating around 6 GHz based on the LiNbO3 thin film
Authors: Tong Xin , Liu Wenjuan , Wen Zhiwei , Liu Zesheng , Xu Qinwen , Zou Yang , Gao Chao , Zhou Jie , Liu Yan , Cai Yao , Sun Chengliang
Published: April 2024

The first asymmetric mode (A1 mode) lamb wave resonator (LWR) with a resonant frequency of 6 GHz based on Z-cut lithium niobate (LN) films is presented. An asymmetric electrode structure with different-sized electrode pads in the center and edged regions has been proposed, which can be used to optimize the distribution of the electric field and decrease acoustic impedance mismatch to improve the target mode. Experiment results reveal that LWRs with an asymmetric electrode structure can successfully enhance the A1 mode, achieving a high effective electromechanical coefficient (

k

eff

2

) of 26%, a quality factor (Q) of 1123, and an excellent figure-of-merit (FOM =

k

eff

2

∙Q) of 262. It demonstrates that asymmetric electrode structure provides a new way to suppress the spurious modes for LWRs and shows a great application prospect in wide-bandwidth and low-loss filters used in the sub-6 G frequency range.
Measurement of aero-engine feature-hierarchy fusion degradation trend based on parameter-adaptive VMD method and improved transformer model
Authors: Lu Junze , Jiang Wei , Xu Yanhe , Chen Zhong , Ni Kaijie
Published: April 2024

The accumulation of operational time in aero-engines leads to irreversible mechanical wear and tear, necessitating accurate measurement of the health evolution trend for effective predictive maintenance, thus reducing the risk of accidents and ensuring personnel safety. In this paper, a parameter-adaptive variational mode decomposition (VMD) method and improved transformer model are proposed to forecast the degradation trend of aero-engine feature hierarchy fusion. Firstly, in order to quantitatively evaluate the engine health evolution process, the health state aggregate indicator (HSAI) is innovatively constructed by employing the deep blend auto-encoder and self-organizing map network, which facilitate the feature-hierarchy fusion of multi-source sensory data. Secondly, for the significant characteristics with nonlinearity and stochastic fluctuation of the HSAI sequence, the multiscale frequency features are extracted by the parameter-adaptive VMD method with the improved gray wolf optimizer, which analyzes the inherent degradation law. Finally, considering the problem of parameter sharing in the transformer model, a simplified mixture of experts routing algorithm is introduced to implement the switch transformer model to further measure the future aero-engine health trends. Extensive experiments on the multi-source dataset of aero-engine confirm that the proposed method accomplishes the more superior performance for health evolution measurement compared with other available methods.
Research on the calculation and evaluation method of transmission efficiency of noncircular planetary gear
Authors: Li Longkun , Dong Changbin , Zhao Gang , Wan Anran , Liu Yongping
Published: April 2024

The torque fluctuation characteristics of noncircular planetary gear (NPG) systems are difficult to obtain, and there is no clear analysis method and evaluation method for transmission efficiency, which seriously affects their service performance. Given that, this article establishes a torque fluctuation model for NPG systems based on the principle of gear meshing and differential geometry theory and methods, taking into account factors such as actual working conditions and speed loads. And proposed, the comprehensive transmission rate, a new method for evaluating the efficiency of NPG systems. By analyzing the actual working conditions of NPG systems, the influence mechanism of alternating load and speed on torque fluctuation and transmission efficiency was explored. The research results indicate that the alternating load can cause an increase in system impact and vibration. The comprehensive transmission rate of NPG systems decreases with increasing rotational speed and increases with increasing load, and is more sensitive to changes in rotational speed. The trend of comprehensive transmission rate and transmission efficiency of NPG systems is basically consistent, indicating that the proposed method of using comprehensive transmission rate to evaluate transmission efficiency is a practical and feasible analysis method. The research results can provide a new method for dynamic measurement and evaluation of torque and transmission efficiency of non-circular gear transmission systems.
An improved envelope spectrum via Hoyer index-gram for bearing fault extraction
Authors: Tian Tian , Tang Guiji , Wang Xiaolong , Sun Jingjing
Published: April 2024

Resonance demodulation is one of the most commonly used methods in rolling bearing fault diagnosis, yet determining the optimal demodulation band has been a significant challenge. The vibration signal from a faulty bearing may include not only periodic fault impulses but also discrete harmonic interferences, random impulses, Gaussian white noise, among others. To enhance fault information and attenuate the impact of interference signals, this paper proposes an improved envelope spectrum via Hoyer index-gram (IESHoyergram). By utilizing the Hoyer index of the spectrum-related enhanced envelope spectrum as the frequency band filtering criterion, the proposed method extracts periodic impulses while suppressing interference from random impulses and other sources. Moreover, owing to the multilevel segmentation based on the different trend components in the spectral correlation spectrogram, IESHoyergram avoids the shortcomings of traditional segmentation methods. The proposed method is validated through both simulated and experimentally acquired data, demonstrating its capability not only to enhance the characteristics of a single fault but also to separate multiple component faults.
An improvement method for pancreas CT segmentation using superpixel-based active contour
Authors: Gao Huayu , Li Jing , Shen Nanyan , Liu Liang , Yang Ying , Hu Peng , Lu Wei
Published: April 2024

Objective. Pancreas is one of the most challenging organs for Computed Tomograph (CT) image automatic segmentation due to its complex shapes and fuzzy edges. It is simple and universal to use the traditional segmentation method as a post-processor of deep learning method for segmentation accuracy improvement. As the most suitable traditional segmentation method for pancreatic segmentation, the active contour model (ACM), still suffers from the problems of weak boundary leakage and slow contour evolution speed. Therefore, a convenient post-processor for any deep learning methods using superpixel-based active contour model (SbACM) is proposed to improve the segmentation accuracy. Approach. Firstly, the superpixels with strong adhesion to edges are used to guide the design of narrowband and energy function. A multi-scale evolution strategy is also proposed to reduce the weak boundary leakage and comprehensively improve the evolution speed. Secondly, using the original image and the coarse segmentation results obtained from deep learning methods as inputs, the proposed SbACM method is used as a post-processor for fine segmentation. Finally, the pancreatic segmentation public dataset TCIA from the National Institutes of Health(NIH, USA) is used for evaluation, and the Wilcoxon Test confirmed that the improvement of proposed method is statistically significant. Main results. (1) the superpixel-based narrowband shape and dynamic edge energy of the proposed SbACM work for boundary leakage reduction, as well as the multi-scale evolution strategy and dynamic narrowband width for the evolution speed improvement; (2) as a post-processor, SbACM can increase the Dice similarity coefficients (DSC) of five typical UNet-based models, including UNet, SS-UNet, PBR UNet, ResDSN, and nnUNet, 2.35% in average and 9.04% in maximum. (3) Based on the best backbone nnUNet, the proposed post-processor performs better than either adding edge awareness or adding edge loss in segmentation enhancement without increasing the complexity and training time of deep learning models. Significance. The proposed SbACM can improve segmentation accuracy with the lowest cost, especially in cases of squeezed fuzzy edges with similar neighborhood , and complex edges.
DPP: deep phase prior for parallel imaging with wave encoding
Authors: Liu Congcong , Cui Zhuo-Xu , Jia Sen , Cheng Jing , Liu Yuanyuan , Lin Ling , Hu Zhanqi , Xie Taofeng , Zhou Yihang , Zhu Yanjie , Liang Dong , Zeng Hongwu , Wang Haifeng
Published: April 2024

Objective. In Magnetic Resonance (MR) parallel imaging with virtual channel-expanded Wave encoding, limitations are imposed on the ability to comprehensively and accurately characterize the background phase. These limitations are primarily attributed to the calibration process relying solely on center low-frequency Auto-Calibration Signals (ACS) data for calibration. Approach. To tackle the challenge of accurately estimating the background phase in wave encoding, a novel deep neural network model guided by deep phase priors is proposed with integrated virtual conjugate coil (VCC) extension. Concretely, within the proposed framework, the background phase is implicitly characterized by employing a carefully designed decoder convolutional neural network, leveraging the inherent characteristics of phase smoothness and compact support in the transformed domain. Furthermore, the proposed model with wave encoding benefits from additional priors, which incorporate transmission sparsity of the latent image and coil sensitivity smoothness. Main results. Ablation experiments were conducted to ascertain the proposed method’s capability to implicitly represent CSM and the background phase. Subsequently, the superiority of the proposed method is demonstrated through confidence comparisons with competing methods, employing 4-fold and 5-fold acceleration experiments. In achieving 4-fold and 5-fold acceleration, the optimal quantitative metrics (PSNR/SSIM/NMSE) are 44.1359 dB/0.9863/0.0008 (4-fold) and 41.2074/0.9846/0.0017 (5-fold), respectively. Furthermore, the generalizability of the proposed method is further validated by conducting acceleration experiments with T1, T2, T2*, and various undersampling patterns. In addition, the DPP delivered much better performance than the conventional methods by exploring accelerated phase-sensitive SWI imaging. In SWI accelerated imaging, it also surpasses the optimal competing method in terms of (PSNR/SSIM/NMSE) with 0.096%/0.009%/0.0017%. Significance. The proposed method enables precise characterization of the background phase in the integrated VCC and wave encoding framework, supported via theoretical analysis and empirical findings. Our code is available at: https://github.com/sober235/DPP.
An optimization method for ITER radial x-ray camera line-of-sight design basing on Bayesian uncertainty analysis
Authors: Xu Sen , Wang Tianbo , Tieulent Raphael , Colette Damien , Mazon Didier , Verdoolaege Geert , Li Jiquan
Published: April 2024

This paper presents a novel uncertainty optimization algorithm for the design of line-of-sight (LOS) systems used in tomographic inversion. By extending Gaussian process tomography from discrete pixel space to continuous function space through Bayesian inference, we introduce an uncertainty function and analyze its typical distributions. We develop an algorithm to minimize the uncertainty, which is then applied to optimize the LOS configuration of the internal camera in the ITER project. Uncertainty analysis and phantom testing are conducted to validate the effectiveness of the proposed algorithm. The results demonstrate improved accuracy and stability in tomographic reconstructions. This study contributes to the advancement of LOS design for tomographic inversion, offering a practical solution for optimizing diagnostic systems in complex experimental settings.
Comprehensive study on catalytic potential of Ti3C2Tx based catalyzer for Dye sensitized solar cells application
Authors: Arka Girija Nandan , Prasad Shashi Bhushan , Singh Subhash
Published: April 2024

Recently Dye-sensitized solar cells (DSSC) have gained significant research limelight for having exceptional photovoltaic potential. However, DSSC became an underdog solar cell due to the use of an expensive transparent conductive layer (FTO/ITO) along with the use of rare earth element Pt to concoct counter electrode (CE). Thus, an attempt has been made to concoct a Ti3C2-TX MXene-based CE to replace both the transparent conductive layer and CE. Herein, relatively larger with less defective Ti3C2 flakes were produced by the minimally intensive layer delamination method, and physical architecture was investigated by X-ray diffraction (XRD) mapping, Field-emission scanning electron microscope (FE-SEM) and Dynamic light scattering (DLS), respectively. MXene flakes were drop cast on a glass substrate by dispersing it in ethanol, isopropyl alcohol, and deionized water, respectively, and found the least sheet resistance, 14.824 Ω/sq by 4-point probe test, owing to superior adsorption force with the glass substrate. Ethanol solvent facilitates optimum interlamellar spacing to promote fast diffusion and transportation. Further, the study was expanded by introducing it to numerous sintering temperatures to find the best result. The result revealed exceptional sheet resistance of 0.08 Ω/sq for the 120℃ sintered sample, which was encouraged by removing water intercalant and occupying H+. Further, the potential of MXene-based counter electrode’s catalytic activity has been studied through electrochemical impedance spectroscopy, Tafel polarization, and Cyclic voltammogram under iodide and triiodide-based electrolytes. The electrochemical study revealed 120℃ sintered sample superior to 140℃ sintered but comparable to Pt CE. 120℃ sintered Ti3C2-based CE performed exceptional 6.27% power conversion efficiency. Thus, this novel study communicates that Ti3C2-TX is a potential replacement for transparent conductive oxide layer and Pt, frequently used in Dye-sensitized solar cell applications.
Investigation of Ohmic contact to plasma-etched n-Al0.5Ga0.5N by surface treatment
Authors: Zhou Shenhui , Ding Yu , Zhuang Zhe , Sang Yimeng , Chen Kai , Xu Feifan , Yu Junchi , Tao Tao , Zhi Ting , Lu Hai , Zhang Rong , Liu Bin
Published: April 2024

We investigated the optimization effects of KOH solution treatment and SiN
x
sacrificial layer treatment on the contact characteristics of V/Al/Ni/Au on plasma-etched n-AlGaN. The results showed that the contacts on n-Al0.5Ga0.5N with both surface treatments are truly Ohmic in nature, while the contacts on untreated plasma-etched samples are still rectifying. Surface atomic concentration analysis revealed that both surface treatment methods effectively reduced the nitrogen vacancies on n-AlGaN induced by plasma etching, which mostly act as acceptor-like states, leading to severe compensation and hindering of the formation of Ohmic contact. Moreover, the operating voltage was reduced by 0.9 V at 20 mA for 285 nm ultraviolet light-emitting diodes, demonstrating that the surface treatment could work well for plasma-etched n-AlGaN Ohmic contacts.
Scalable electromagnetic energy harvester for wind turbine rotor blade applications
Authors: Schlögl Matthias , Schneider Michael , Schmid Ulrich
Published: April 2024

One of the biggest challenges in structural health monitoring for rotor blades in wind turbines is to provide enough energy to power wireless sensor nodes. Batteries are not an adequate solution due to their limited lifetime and conventional cabling fails due to the rotation of the rotor blade. Therefore, we present an electromagnetic energy harvester that is specifically designed to be operated inside rotor blades and can generate a sufficient amount of energy. It uses the changing gravitational force vector to move a permanent magnet in a tube and converts this mechanical into electrical energy by coils arranged around the tube. Finite element methods simulations were performed to estimate the generated energy and an extensive parameter sweep of several key design parameters provided guidance for an optimized performance of a prototype. This device was characterized in the lab followed by a field test in a wind turbine where it was operated for several days and provided a continuous and rectified power of 6 mW, enough to power conventional wireless accelerometers, typically used within a predictive maintenance concept for the vibrational monitoring of rotor blades.
An electromechanically driven dielectric elastomer based tunable reflector
Authors: Kashyap Kartik , Agrawal Yamnesh , Kumar Ajay , Joglekar M M
Published: April 2024

Deformable optics offer numerous advantages over conventional optical assemblies, including compactness, cost-effectiveness, efficiency, and flexibility. This study focuses on a reflector based on dielectric elastomer actuators (DEAs) with an internal fluid (air) coupling. DEAs are a class of electroactive materials adept at accommodating substantial actuation strains and rapid responses. Fluid distributed between the active and passive parts remains entirely enclosed by the device and transmits actuation pneumatically. Dynamic maneuvers conducted through a series of controlled electrical signals demonstrate proper control over optical characteristics. However, DEs exhibit inherent flaws in dynamic actuation, referred to as instabilities, which are mitigated by applying an initial pre-stretch. The study identifies optimal parameters that confer stability to the reflector: minimum to no creep, zero residual vibrations, and low viscous losses. An analytical framework is developed to assess device performance, focusing on the spherical curvature assumption that closely resembles the behavior of tunable spherical reflectors. Additionally, an optical bench setup is employed to demonstrate the relationship between focal length and applied pressure. Notably, this paper underscores the potential of a DE-based variable focal length reflector to function effectively within a dynamic environment.
Estimation of local arterial stiffness using non-invasive flow measurements: a study on a stenosed carotid artery
Authors: Haq Shamsul , Gul Raheem , Siddiqui Nasir
Published: April 2024

Arterial stiffness is a well-established independent prognostic bio-marker in the human cardiovascular system (CVS). Despite its value as a predictive bio-marker, the inclusion of vascular stiffness into standard clinical procedures or guidelines is limited. This has come about as a result of the abundance of tools created to estimate and evaluate local arterial stiffness in people. This study employs a non-invasive technique to measure local arterial stiffness in the human carotid arteries using proximal flow measurements. Within this work, a viscoelastic lumped-parameter (0D) model of the carotid arteries is developed in complement with the non-invasive flow measurements obtained from the Doppler ultrasound. Further, concepts of sensitivity analysis and parameter estimation are applied to estimate arterial stiffness using the flow measurement taken at the common carotid artery (CCA). After the successful estimation of arterial stiffness in CCA, results show good agreement between model simulations and actual measurement.
Nonlinearity effects on thermal transport properties of a mass-spring chain
Authors: Akbari Chaleshtori Taghi , Rabani Hassan , Mardaani Mohammad
Published: April 2024

Using Green’s function technique, we present a self-consistent formalism to study the phonon transport properties of an extended nonlinear mass-spring chain. We calculate the phonon transmission coefficient, thermal conductivity, and specific heat for some chains with different configurations of masses feeling the nonlinearity potential. The numerical results show that in a critical value of the nonlinearity coefficient, a sharp decrease in thermal conductivity will be observed. The same scenario happens in a critical temperature proportional to the inverse of the nonlinearity coefficient for the specific heat. Indeed, thermal conductor-insulator transition can occur in the system depending on the strength and distribution of nonlinearity. The model can aid our understanding of the effect of lattice nonlinearity on the thermal properties of one-dimensional materials to design the thermal switches.