bluuebunny/crossref_metadata_2025 huggingface dataset:
Invariant polarization switching kinetics in an (Al0.8Sc0.2)N film with frequency and temperature
Authors: Yasuoka Shinnosuke , Mizutani Ryoichi , Ota Reika , Shiraishi Takahisa , Shimizu Takao , Okamoto Kazuki , Uehara Masato , Yamada Hiroshi , Akiyama Morito , Funakubo Hiroshi
Published: November 2023

In this study, the switching kinetics in a (001)-out-of-plane-oriented (Al0.8Sc0.2)N thin film were systematically investigated as a function of temperature and frequency. The switching behavior followed the Kolmogorov–Avrami–Ishibashi model within the temperature and write-pulse width ranges of 300–473 K and 10 Hz–600 kHz, respectively. The switching speed increased linearly with the electric field, even at high electric fields. The frequency dependence of the coercive field (Ec) evaluated at room temperature revealed that the scaling regime of the domain-wall propagation did not transition to the flow regime, and the switching velocity of the domain increased linearly with the electric field even at high frequencies up to 600 kHz. The invariant domain-wall motion regime implies the potential of using (Al,Sc)N films for high-frequency applications. In addition, a formula for estimating the coercive field of an (Al,Sc)N film was derived by fitting the parameters obtained from the study of switching behavior. The formula indicated that the switching electric field tends to become insensitive to frequency as temperature increases. Moreover, the frequency dependency of the field was minimal even at room temperature. This is a useful index for estimating the drive voltage at the operating frequency and temperature.
SH-BAW devices with abnormal mass-loading effect for chemical sensing
Authors: Shen Junjie , Chen Haibo , Shi Zimeng , Kong Linghui , Zhang Yunjing , Li Lingfeng , Li Peng , He Xingli
Published: November 2023

Surface acoustic wave (SAW) devices are promising for chemical and biological sensing applications. This work studies the basic operating principles and the physical behaviors of the “Rayleigh”-SAW and the “Shear Horizontal (SH-)” bulk acoustic wave (BAW), particularly in relation to the chemisorption process. A complete 3D delay line SAW model is developed and performed by the finite element analysis, and a methodology was introduced for characterizing the transmission characteristics (S21) of these devices. Notably, our investigation unveils an intriguing phenomenon in the behavior of SH-BAW in response to loading mass. We observed an anomalous shift in the central frequency, which increases as the chemical adsorbate concentration rises. Leveraging these insights, we designed and constructed a SAW-based gas sensor, and the vinyl-terminated polydimethylsiloxane was synthesized for the detection of chloroform, a challenging pollutant to identify. Through a comparative study, we illustrate distinct responses of Rayleigh-SAW and SH-BAW devices to accumulated loading mass and gaseous contaminants. These experimental results validate and corroborate our simulations. This work demonstrates a unique mass-loading effect exhibited by SH-BAW devices, which differs from the existing theories. These findings offer the opportunity to refine and enhance models for accurately describing the functionality of delay line SAW sensors, thereby contributing to improved sensor reliability.
Addressing three-body fragmentation of methane dication using “native frames”: Evidence of internal excitation in fragments
Authors: Rajput Jyoti , Garg Diksha , Cassimi A. , Fléchard X. , Rangama J. , Safvan C. P.
Published: November 2023

The three body fragmentation of methane dication has been studied using the technique of cold target recoil ion momentum spectroscopy. The process is initiated by impact of energetic Ar9+ ions on neutral methane and the data is subsequently collected in coincidence with Ar8+ projectile. By analysing the dissociation channels leading to (H + H+ + CH2+) and (H + H2+ + CH+) fragments, it is concluded that these fragments are formed in a sequential manner via formation of molecular intermediates CH3+ and CH2+ respectively. It is shown that these molecular intermediates carry a few eVs as their internal energies, part of which is released when they emit an H-atom with the open possibility that the final detected fragments may still be internally excited. This was accomplished by analysing the two-steps of the sequential process in their own native frames. For a molecular system having three-dimensional structure, our results prove to be an ideal example to highlight the importance of using native frames for correct interpretation of the obtained results. Our results indicate that the dissociation of methane dication can be a major source of production of H-atoms in addition to H+ fragments with the probability of the two being of similar order.
Hydrophobicity of molecular-scale textured surfaces: The case of zeolitic imidazolate frameworks, an atomistic perspective
Authors: Le Donne Andrea , Littlefair Josh D. , Tortora Marco , Merchiori Sebastiano , Bartolomé Luis , Grosu Yaroslav , Meloni Simone
Published: November 2023

Hydrophobicity has proven fundamental in an inexhaustible amount of everyday applications. Material hydrophobicity is determined by chemical composition and geometrical characteristics of its macroscopic surface. Surface roughness or texturing enhances intrinsic hydrophilic or hydrophobic characteristics of a material. Here we consider crystalline surfaces presenting molecular-scale texturing typical of crystalline porous materials, e.g., metal-organic frameworks. In particular, we investigate one such material with remarkable hydrophobic qualities, ZIF-8. We show that ZIF-8 hydrophobicity is driven not only by its chemical composition but also its sub-nanoscale surface corrugations, a physical enhancement rare amongst hydrophobes. Studying ZIF-8’s hydrophobic properties is challenging as experimentally it is difficult to distinguish between the materials’ and the macroscopic corrugations’ contributions to the hydrophobicity. The computational contact angle determination is also difficult as the standard “geometric” technique of liquid nanodroplet deposition is prone to many artifacts. Here, we characterise ZIF-8 hydrophobicity via: (i) the “geometric” approach and (ii) the “energetic” method, utilising the Young–Dupré formula and computationally determining the liquid–solid adhesion energy. Both approaches reveal nanoscale Wenzel-like bathing of the corrugated surface. Moreover, we illustrate the importance of surface linker termination in ZIF-8 hydrophobicity, which reduces when varied from sp3 N to sp2 N termination. We also consider halogenated analogues of the methyl-imidazole linker, which promote the transition from nanoWenzel-like to nanoCassie–Baxter-like states, further enhancing surface hydrophobicity. Present results reveal the complex interface physics and chemistry between water and complex porous, molecular crystalline surfaces, providing a hint to tune their hydrophobicity.
Transferability of interatomic potentials for germanene (2D germanium)
Authors: Maździarz Marcin
Published: November 2023

The capacities of various interatomic potentials available for elemental germanium, with the scope to choose the potential suitable for the modeling of germanene (2D germanium) allotropes,f were investigated. Structural and mechanical properties of the flat, low-buckled, trigonal dumbbell, and large honeycomb dumbbell single-layer germanium (germanene) phases, were obtained using the density functional theory and molecular statics computations with Tersoff, modified embedded atom method, Stillinger–Weber, environment-dependent interatomic potential, ReaxFF, and machine-learning-based interatomic potentials. A systematic quantitative comparative study and discussion of the findings are given.
Observation of dislocation-controlled domain nucleation and domain-wall pinning in single-crystal BaTiO3
Authors: Jiang Tianshu , Ni Fan , Recalde-Benitez Oscar , Breckner Patrick , Molina-Luna Leopoldo , Zhuo Fangping , Rödel Jürgen
Published: November 2023

Electro-mechanical interactions between topological defects and domain walls play a key role in the macroscopic response of bulk and thin-film ferroelectrics. The applications of ferroelectrics are derived from their inherent ability to nucleate new domains and to move the domain walls that separate adjacent domains. Here, we report dislocation-mediated domain nucleation in single-crystal BaTiO3, achieved by dislocations generated via high-temperature uniaxial compression on a notched sample. We also present a direct observation of domain-wall pinning of 90° ferroelastic domain walls by dislocations using in situ transmission electron microscopy. Dense and well-aligned “forest” dislocations, featuring {100}⟨100⟩ slip systems oriented in the out-of-plane [001] direction, exclusively nucleate in-plane domain variants. We reveal that the 90° domain walls are strongly pinned by imprinted dislocations due to the presence of their associated stress fields. Our findings may advance our understanding of the control of defects in ferroelectrics and propose a strategy applicable to both emerging nanoelectronic and bulk applications.
β-FeSi2: A high refractive index candidate material for infrared bandpass filters
Authors: Zhang Xuanwei , Namura Kyoko , Suzuki Motofumi
Published: November 2023

Bandpass filters (BPFs) are optical filters with significantly high transmittance in a specific wavelength range and low transmittance on both sides. Infrared BPFs can reduce system losses and overheating caused by other light wavelengths owing to their ability to selectively transmit infrared light of the desired wavelength. This article discusses the potential of using a high refractive index material, β-FeSi2, in BPFs. To the best of our knowledge, no studies have applied β-FeSi2 to infrared BPFs. Simulation results showed that its high refractive index allows the excellent performance of the BPF to be achieved using a multilayer thin film structure with only three layers. Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy results showed that the β-FeSi2 thin film exhibited the lowest absorptance of approximately 0 when the correct stoichiometry (Fe:Si = 1:2) was achieved through co-sputtering. Based on these findings, a β-FeSi2/SiO2/β-FeSi2 multilayer thin film was designed to fabricate the BPF. The fabricated BPF exhibited a narrow peak and achieved a peak transmittance exceeding 80%. This suggested that β-FeSi2 is a promising material for fabricating infrared BPFs. Utilizing these filters is expected to yield significant efficiency improvements and reduce losses across various applications, including thermophotovoltaics and infrared heaters.
Research on the element structure and surface current distribution of metasurface based on characteristic mode analysis
Authors: Ni Chun , Xie Xin , Zhang Liang
Published: November 2023

Scientific research has shown that the geometric structure of the metasurface has a significant impact on its ability to control the propagation of electromagnetic waves. The control of surface current can be achieved by designing the shape of the metasurface unit cell. In this paper, the traditional metasurface is studied using characteristic mode analysis, and a modified metasurface is proposed, which consists of 4 × 4 hexagonal rings with an asymmetric concave interior. The modified metasurface controls the distribution of surface current by increasing the path of surface current, thus lowering the frequency of modal significance. In addition, due to the special asymmetric concave interior, the frequency difference of different modal currents increases, leading to the expansion of the operating bandwidth of modal currents. A metasurface antenna is fabricated and measured for proof of concept. With a size of 0.69λL × 0.69λL × 0.06λL (λL is the wavelength in free space at the lowest operating frequency), the designed antenna achieves a −10 dB impedance band of 40%, 3 dB axial ratio band of 19.4%, and boresight gain of 8 dBi.
Numerical study of solution structure and nonlinear behavior of Dean flow with vortex structure in a bending square duct
Authors: Hussen Selim , Islam Md. Rashedul , Mondal Rabindra Nath
Published: November 2023

Fluid flow and heat transfer in bending channels are topics of much research interest because of increasing demand in various fields, particularly in the medical and industrial arenas. This paper presents a numerical study of fluid flow and heat transfer in a bending channel with a square cross section. Numerical calculations using spectral methods were performed for a curvature of 0.001 and a Dean number (Dn) in the range of 0<Dn≤5000. A temperature difference was maintained between the horizontal walls for a Grashof number of Gr = 1000, with the bottom wall heated and the outer and inner walls thermally insulated. Applying Newton–Raphson iteration and path continuation, two branching structures of steady solutions with two to eight vortices were obtained. The first branch comprises multi-vortex up to eight and it occurs at Dn≥3500 while the second branch comprises to multi-vortex up to a maximum of four. The first branch forms symmetric solution while the second branch for its complexity forms asymmetric solutions. For unsteady solutions, time-evolution calculations were performed to investigate the nonlinear behavior, and it was found that with increasing Dn, the unsteady flow experienced various flow instabilities. The time evolution was plotted in phase space to clarify the unsteady flow characteristics. Distinctive contours of the secondary flow patterns, streamwise velocity distributions, and isotherms were also obtained, and the unsteady flow was found to comprise two to six vortices. Finally, convective heat transfer was explored by obtaining temperature contours, and the secondary flow was found to magnify the convective heat transfer significantly. Because of the increase of several secondary vortices in the chaotic solutions, heat transfer occurred markedly in the flow.
Advancing thermoelectric materials discovery through semi-supervised learning and high-throughput calculations
Authors: Jia Xue , Yao Honghao , Yang Zhijie , Shi Jianyang , Yu Jinxin , Shi Rongpei , Zhang Haijun , Cao Feng , Lin Xi , Mao Jun , Wang Cuiping , Zhang Qian , Liu Xingjun
Published: November 2023

The data-driven machine learning technique is widely used to assist in accelerating the design of thermoelectric materials. In this study, we proposed a positive and unlabeled learning (PU learning) method, a semi-supervised learning, to train a classifier to distinguish the positive samples from the unlabeled samples, in which the positive class was labeled by matching the formulas in our dataset with the published article titles. The probabilities that the unlabeled materials belong to the positive class were predicted by PU learning, and 40 candidate thermoelectric materials were determined. The transport properties were calculated by high-throughput first-principles calculations, among which 8 p-type and 12 n-type materials have the maximum theoretical zT values greater than 1. Specifically, a series of AX2 binary compounds, (Cd/Zn)(GaTe2)2 ternary compounds, and Cs(Dy/Ho/Tb)2Ag3Te5 quaternary compounds deserve further investigations in the future.
Capacitive sensing for measuring the conduction zone of low density pentaerythritol tetranitrate (PETN)
Authors: Edgeley James , Braithwaite Chris , Lee Elizabeth , Drake Rod
Published: November 2023

We present a novel diagnostic system, based on the principle of capacitive sensing, capable of detecting the conduction zone of detonating explosives. The method relies on measuring the change in the capacitive coupling between a printed circuit and its surroundings, induced by an increase in local conductivity. A high frequency wave generator provides the driving signal, which is modified by the change in coupling. This method boasts greater sensitivity than existing conductivity-based techniques, with comparable spatial and temporal resolution. The subject material was pentaerythritol tetranitrate (PETN) powder, pressed into low density (50%–85% theoretical maximum density) cylindrical columns. Previous attempts to measure the reaction zone of low density PETN have faced difficulties because of its short length and low conductivity compared to other explosives. The PETN was initiated using a laser flyer detonator in order to reach detonation promptly and with a minimum of electrical noise. Application of the capacitive sensor diagnostic and subsequent analysis yielded a density dependent steady-state reaction zone length of between 45 and 78 μm.
Experimental evidence of hole injection through V-defects in long wavelength GaN-based LEDs
Authors: Marcinkevičius Saulius , Ewing Jacob , Yapparov Rinat , Wu Feng , Nakamura Shuji , Speck James S.
Published: November 2023

Hole injection through V-defect sidewalls into all quantum wells (QWs) of long wavelength GaN light emitting diodes had previously been proposed as means to increase efficiency of these devices. In this work, we directly tested the viability of this injection mechanism by electroluminescence and time-resolved photoluminescence measurements on a device in which QW furthest away from the p-side of the structure was deeper, thus serving as an optical detector for presence of injected electron–hole pairs. Emission from the detector well confirmed that, indeed, the holes were injected into this QW, which could only take place through the 101¯1 V-defect sidewalls. Unlike direct interwell transport by thermionic emission, this transport mechanism allows populating all QWs of a multiple QW structure despite the high potential barriers in the long wavelength InGaN/GaN QWs.
Nanomechanical vibrational response from electrical mixing measurements
Authors: Samanta C. , Czaplewski D. A. , Bonis S. L. De , Møller C. B. , Tormo-Queralt R. , Miller C. S. , Jin Y. , Pistolesi F. , Bachtold A.
Published: November 2023

Driven nanomechanical resonators based on low-dimensional materials are routinely and efficiently detected with electrical mixing measurements. However, the measured signal is a non-trivial combination of the mechanical eigenmode displacement and an electrical contribution, which makes the extraction of the driven mechanical response challenging. Here, we report a simple yet reliable method to extract solely the driven mechanical vibrations by eliminating the contribution of pure electrical origin. This enables us to measure the spectral mechanical response as well as the driven quadratures of motion. This method is crucial for nanomechanical vibrations in the nonlinear regime, since the shape of the mechanical response depends on the physics at work. We further show how to calibrate the measured signal into units of displacement. Our method marks a key step forward in the study of nanoelectromechanical resonators based on low-dimensional materials in the nonlinear regime.
Developing the agroecological niche in Nicaragua: The roles of knowledge flows and intermediaries
Authors: Schiller Katharina J. F. , Klerkx Laurens , Salazar Centeno Dennis José , Poortvliet P. Marijn
Published: November 2023

Supporting transitions to sustainable, resilient agri-food systems is important to ensure stable food supply in the face of growing climate extremes. Agroecology, or diversified farming systems based on ecological principles, can contribute to such systems. Based on a qualitative case study of Nicaragua, a forerunner in agroecology, this paper unpacks an ongoing transition to agroecology, focusing on how the transition has been shaped by knowledge flows and intermediary actors. Using a niche development framework based on knowledge processes, we analyze the growth of the agroecological niche in Nicaragua over three phases of niche development. The findings show how knowledge processes’ emphases have shifted over time, as have functions enacted by intermediaries. Dedicated, diversified intermediaries have been key in creating momentum for agroecology, as have individual actors moving between niche and regime. Agency in niche development has come from both niche and regime actors. Finally, we find that Nicaragua’s transition to agroecology has been ambiguous: While the niche has succeeded in changing the mainstream selection environment to its favor in some arenas, transition dynamics lag in others. Drawing lessons from this ambiguity, we suggest entry points for broader systems change, such as market stimulation, value chain development, phase-out policies, and supportive policy in related arenas. We also point out possible actions for niche actors such as integration of financial and commercial actors into niches and creation of dedicated market-focused intermediaries. Our results provide evidence of an ongoing transition and action points for supporting niche development in (sustainable agri-food) transitions around the globe.
The historical dismantling of tramways as a case of destabilisation and phase-out of established system
Authors: Turnheim Bruno
Published: November 2023

Addressing sustainability challenges requires fundamental transformations in electricity, heat, mobility, and agri-food systems. To do so, research and policy efforts tend to emphasise the importance of fostering new, more sustainable systems through innovation. Instead, this paper focuses explicitly on the “flipside” of innovation: The fate of established systems faced with their potential destabilisation and decline. It is argued that any transition in consumption-production systems involves a combination of innovation (something new emerges) and destabilisation (something old is being challenged). To examine the role of destabilisation, decline, and phase-out for policy and practice efforts, this paper advances conceptual and empirical contributions. Conceptually, it elaborates a framework based on three interacting destabilisation mechanisms: The build-up of pressures, strategic responses by central system actors, and changing commitments to reproductive activities. Empirically, it draws on the historic dismantling of electric tramways in France. The decline of the tramway in France followed a gradual erosion pattern resulting from the long-term degradation of technical, political, and economic conditions, which was accelerated by a relatively rapid phase-out programme. A discussion section offers insights on the temporality of destabilisation, the context of phase-out decisions, and the interaction of destabilisation and innovation processes.
The big business of sustainable food production and consumption: Exploring the transition to alternative proteins
Authors: Mylan Josephine , Andrews John , Maye Damian
Published: November 2023

A widespread sense of the unsustainability of the food system has taken hold in recent years, leading to calls for fundamental change. The role of animal agriculture is central to many of these debates, leading to interest in the possibility of a “protein transition,” whereby the production and consumption of animal-derived foods is replaced with plant-based substitutes or “alternative proteins.” Despite the potential sustainability implications of this transition, the developmental trajectories and transformative potential of the associated technologies remain underexplored. This article sheds light on these dynamics by addressing two questions: 1) how have alternative protein innovations developed over the past three decades, and 2) what explains their more recent acceleration? To answer these questions, the article makes an empirical analysis of four alternative protein innovations, and the partial destabilization of the animal agriculture system between 1990 and 2021, guided by the multi-level perspective. The analysis highlights an intensification in corporate engagement with alternative protein development and diffusion. This intensification is judged to be consistent with the beginnings of a wider corporate reorientation, occurring alongside a rise in pressures on the animal agriculture system, notably an increasing scientific consensus and societal awareness of the links between climate change and meat-intensive diets. The paper demonstrates how differences in technological maturity across the niche innovations have resulted in potentially transformative pressures, which are consistent with an emerging sustainability transition, manifesting differently in terms of the extent of diffusion of the alternative protein niches.
A B cell–driven EAE mouse model reveals the impact of B cell–derived cytokines on CNS autoimmunity
Authors: Thomann Anna S. , McQuade Courtney A. , Pinjušić Katarina , Kolz Anna , Schmitz Rosa , Kitamura Daisuke , Wekerle Hartmut , Peters Anneli
Published: November 2023

In multiple sclerosis (MS), pathogenic T cell responses are known to be important drivers of autoimmune inflammation. However, increasing evidence suggests an additional role for B cells, which may contribute to pathogenesis via antigen presentation and production of proinflammatory cytokines. However, these B cell effector functions are not featured well in classical experimental autoimmune encephalomyelitis (EAE) mouse models. Here, we compared properties of myelin oligodendrocyte glycoprotein (MOG)-specific and polyclonal B cells and developed an adjuvant-free cotransfer EAE mouse model, where highly activated, MOG-specific induced germinal center B cells provide the critical stimulus for disease development. We could show that high levels of MOG-specific immunoglobulin G (IgGs) are not required for EAE development, suggesting that antigen presentation and activation of cognate T cells by B cells may be important for pathogenesis. As our model allows for B cell manipulation prior to transfer, we found that overexpression of the proinflammatory cytokine interleukin (IL)-6 by MOG-specific B cells leads to an accelerated EAE onset accompanied by activation/expansion of the myeloid compartment rather than a changed T cell response. Accordingly, knocking out IL-6 or tumor necrosis factor α in MOG-specific B cells via CRISPR-Cas9 did not affect activation of pathogenic T cells. In summary, we generated a tool to dissect pathogenic B cell effector function in EAE development, which should improve our understanding of pathogenic processes in MS.
Generically partisan: Polarization in political communication
Authors: Novoa Gustavo , Echelbarger Margaret , Gelman Andrew , Gelman Susan A.
Published: November 2023

American political parties continue to grow more polarized, but the extent of ideological polarization among the public is much less than the extent of perceived polarization (what the ideological gap is believed to be). Perceived polarization is concerning because of its link to interparty hostility, but it remains unclear what drives this phenomenon. We propose that a tendency for individuals to form broad generalizations about groups on the basis of inconsistent evidence may be partly responsible. We study this tendency by measuring the interpretation, endorsement, and recall of category-referring statements, also known as generics (e.g., “Democrats favor affirmative action”). In study 1 (n= 417), perceived polarization was substantially greater than actual polarization. Further, participants endorsed generics as long as they were true more often of the target party (e.g., Democrats favor affirmative action) than of the opposing party (e.g., Republicans favor affirmative action), even when they believed such statements to be true for well below 50% of the relevant party. Study 2 (n= 928) found that upon receiving information from political elites, people tended to recall these statements as generic, regardless of whether the original statement was generic or not. Study 3 (n= 422) found that generic statements regarding new political information led to polarized judgments and did so more than nongeneric statements. Altogether, the data indicate a tendency toward holding mental representations of political claims that exaggerate party differences. These findings suggest that the use of generic language, common in everyday speech, enables inferential errors that exacerbate perceived polarization.
Kinesin-1 patterns Par-1 and Rho signaling at the cortex of syncytial embryos of Drosophila
Authors: Li Long , Zhang Na , Beati Seyed Amir Hamze , De las heras chanes Jose , di Pietro Florencia , Bellaiche Yohanns , Müller Hans-Arno J. , Großhans Jörg
Published: November 2023

The cell cortex of syncytial Drosophila embryos is patterned into cap and intercap regions by centrosomes, specific sets of proteins that are restricted to their respective regions by unknown mechanisms. Here, we found that Kinesin-1 is required for the restriction of plus- and minus-ends of centrosomal and non-centrosomal microtubules to the cap region, marked by EB1 and Patronin/Shot, respectively. Kinesin-1 also directly or indirectly restricts proteins and Rho signaling to the intercap, including the RhoGEF Pebble, Dia, Myosin II, Capping protein-α, and the polarity protein Par-1. Furthermore, we found that Par-1 is required for cap restriction of Patronin/Shot, and vice versa Patronin, for Par-1 enrichment at the intercap. In summary, our data support a model that Kinesin-1 would mediate the restriction of centrosomal and non-centrosomal microtubules to a region close to the centrosomes and exclude Rho signaling and Par-1. In addition, mutual antagonistic interactions would refine and maintain the boundary between cap and intercap and thus generate a distinct cortical pattern.
Application of Swin-Unet for pointer detection and automatic calculation of readings in pointer-type meters
Authors: Zhang Wenbo , Ji Dongsheng , Yang Wen , Zhao Qianchuan , Yang Lina , Zhuoma Caidan
Published: November 2023

Pointer-type meters are widely used in military, industrial, and aerospace applications. In this paper, we propose a method to automatically calculate the readings of pointer-type meters that exhibits strong robustness to various situations, such as complex backgrounds, tilted meters, blurred images, and meter images with uneven illumination. First, the mask maps of scale and pointers are obtained using the Swin-Unet semantic segmentation network. For the mask map of scale, the Swin Transformer image classification network is used to identify the values of the scale and the coordinates of the centroids of the scale, and for the mask map of the pointer, the least skeleton circle method is proposed to fit the linear equation of the pointer. Second, the influence of the pointer and several adjacent scale on the meter reading is considered, and the weighted angle method (WAM) is proposed to calculate the meter reading. In order to verify the robustness of the algorithm in this paper, the pointer detection method is compared with the traditional pointer detection method, and it is found that the pointer detection method in this paper works better, and the pointer detection algorithm in this paper is applied to different semantic segmentation results, and it is verified that the pointer detection algorithm in this paper can be well adapted to different semantic segmentation results. This paper also compares the proposed algorithm with the existing meter reading calculation methods. The experiments show that using WAM on uncorrected meter images reduces the error by 30% compared with the traditional angle method, and using WAM on corrected meter images reduces the error by about 50%, which finally verifies the effectiveness of the algorithm in this paper.
Research on a system for the diagnosis and localization of conveyor belt deviations in belt conveyors
Authors: Wu Lei , Li Junxia , Zhang Hongyu , Zhang Wei , Huang Shuai
Published: November 2023

To address the shortcomings of existing conveyor belt deviation detection methods, such as the small detection range and slow detection speed, a method that utilizes machine vision technology to detect belt deviations in belt conveyors is proposed. A track-type inspection robot was used to collect real-time running images of a conveyor belt; Wiener filtering was carried out, grayscale processing was used, Canny edge detection, Hough transform and least squares fitting operations were used to extract the straight lines of the edges of the conveyor belt, and the offset from the straight lines of the conveyor belt under normal running conditions was calculated. To address the cumulative error problem caused by the long time and long distance in the process of locating the wheel odometer, a joint localization technology that used radio frequency identification (RFID) and a wheel odometer was proposed, and the error correction was carried out for a rotary encoder by using the RFID technology. The experimental results demonstrate that the detection method achieved a detection accuracy of over 92.1% with a detection speed of up to 31 FPS. This method enables the fast and precise identification of conveyor belt deviations, and it satisfies the requirements for real-time detection for belt conveyors. The location accuracy of the localization system that combined RFID and a wheel odometer was able to reach the centimeter level, and the system could accurately locate the positions of belt deviations. This is of vital significance for ensuring safety and efficiency in production by enterprises.
An image fusion-based method for recovering the 3D shape of roll surface defects
Authors: Xu Ji , Xu Feng , Lou Chenxukun , Zhang Liping , Guo Hun , Zuo Dunwen
Published: November 2023

Most of the existing studies on roll surface defects focus on qualitative detection and lack quantitative analysis, while the commonly used methods for detecting the three-dimensional shape of small objects such as defects are the stylus method, laser scanning method, and structured light scanning method, but these methods are difficult to accurately measure the complex defect variations on the roll surface. In this paper, we propose a method for recovering the 3D shape of roll surface defects based on image fusion. The traditional 3D reconstruction problem is transformed into a 2D image fusion problem using a focusing method. The non-subsampled shear wave transform is used as the base algorithm for image fusion, combined with an enhanced fusion strategy called modified multi-state pulse-coupled neural network to obtain a fully focused image. The method achieves 3D shape recovery of defects by modeling the relationship between the defect depth, the fully focused image, and the original image. To evaluate the performance of the method, experiments were carried out using data involving craters and scratches on the roll surface. This method significantly improves the quality of defect detection images, with a 98% better gradient and a 28% increase in overall image quality. Additionally, it keeps 3D reconstruction errors under 4%, ensuring high accuracy and noise resistance.
Electromagnetic force behavior of superconducting bulks passing electromagnetic turnout
Authors: Peng Can , Wang Xuanbo , Zhou Xucheng , Lei Wuyang , Liu Xiaoning , Gerasimenko Anastasiia A , Deng Zigang
Published: November 2023

High temperature superconducting (HTS) Maglev is a promising technology owing to its excellent electromagnetic properties of non-control stability and frictionless. As a critical component of HTS Maglev, the turnout poses challenges due to the use of the permanent magnet guideways (PMGs) that are difficult to switch mechanically. With simple structure and rapid responsiveness, electromagnetic turnout has become an interesting research field of HTS Maglev. The electromagnetic turnout is designed to control the electromagnetic force of the HTS bulks by adjusting the magnetic field using an electromagnetic-permanent magnetic structure. However, the magnetic field generated by the combination of the electromagnet and the PMs inevitably differs from the magnetic field above the PMGs, affecting the electromagnetic force behavior of the HTS bulks. To guarantee optimal performance of the electromagnetic turnout, the variation process of the magnetic field peak above the turnout is analyzed. Furthermore, a three-dimensional superconducting model based on the
H
-formulation and motion equation is built to obtain the electromagnetic force of the HTS bulks passing the turnout. It’s concluded that higher cooling heights in the preparation and higher working heights in the turnout area are recommended to reduce the magnetic resistance and avoid the destabilizing effect. In addition, the smaller bulks experience greater resistance, and the longer bulks are prone to nodding, while the wider bulks are prone to shaking above the turnout. Properly matching HTS bulks with operating conditions improves electromagnetic force behavior and benefits HTS Maglev turnout passability.
Coherent manipulation of nuclear spins in the strong driving regime
Authors: Yudilevich Dan , Salhov Alon , Schaefer Ido , Herb Konstantin , Retzker Alex , Finkler Amit
Published: November 2023

Spin-based quantum information processing makes extensive use of spin-state manipulation. This ranges from dynamical decoupling of nuclear spins in quantum sensing experiments to applying logical gates on qubits in a quantum processor. Fast manipulation of spin states is highly desirable for accelerating experiments, enhancing sensitivity, and applying elaborate pulse sequences. Strong driving using intense radio-frequency (RF) fields can, therefore, facilitate fast manipulation and enable broadband excitation of spin species. In this work, we present an antenna for strong driving in quantum sensing experiments and theoretically address challenges of the strong driving regime. First, we designed and implemented a micron-scale planar spiral RF antenna capable of delivering intense fields to a sample. The planar antenna is tailored for quantum sensing experiments using the diamond’s nitrogen-vacancy (NV) center and should be applicable to other solid-state defects. The antenna has a broad bandwidth of 22 MHz, is compatible with scanning probes, and is suitable for cryogenic and ultrahigh vacuum conditions. We measure the magnetic field induced by the antenna and estimate a field-to-current ratio of

113
±
16

 G/A, representing a six-fold increase in efficiency compared to the state-of-the-art, crucial for cryogenic experiments. We demonstrate the antenna by driving Rabi oscillations in 1H spins of an organic sample on the diamond surface and measure 1H Rabi frequencies of over 500 kHz, i.e.

π

-pulses shorter than 1 

μ

s

—an order of magnitude faster than previously reported in NV-based nuclear magnetic resonance (NMR). Finally, we discuss the implications of driving spins with a field tilted from the transverse plane in a regime where the driving amplitude is comparable to the spin-state splitting, such that the rotating wave approximation does not describe the dynamics well. We present a simple recipe to optimize pulse fidelity in this regime based on a phase and offset-shifted sine drive, which may be optimized in situ without numerical optimization procedures or precise modeling of the experiment. We consider this approach in a range of driving amplitudes and show that it is particularly efficient in the case of a tilted driving field. The results presented here constitute a foundation for implementing fast nuclear spin control in various systems.
Study on the acoustic performance of bending metasurface with ultra-thin broadband quasi-perfect sound absorption
Authors: Cheng Baozhu , Zeng QiuYu , Liu Yang , Weng Jiansong , Li Bin , Hou Hong
Published: November 2023

In order to achieve low-frequency broadband noise control under subwavelength thickness, this paper established a theoretical model for calculating the sound absorption coefficient of curled acoustic metasurface (CAM) composed of embedded hole, equal width curled channel, and gradient width curled channel, which is based on the thermal viscosity equivalent model and impedance equivalent model. Considering the over resistance effect caused by multi-unit composite structure, a multi-parameter control strategy was used to design bending acoustic metasurface (BAM) units for perfect sound absorption at four discrete frequencies of 546 Hz, 563 Hz, 585 Hz, and 601 Hz, which is based on the complex frequency plane method. and the thicknesses of these unites are only

λ
/

52

(1.2 cm). The broadband and efficient sound absorption effect of the four parallel composite BAM units was theoretically studied. The simulation and experiment verified that the composite BAM not only achieved perfect sound absorption at 573 Hz with a subwavelength thickness of 12 mm, but also had an efficient sound absorption(α > 0.8) frequency band of 512Hz-621Hz, with a bandwidth up to 109 Hz. The research in this paper provides a certain theoretical basis for the design of low-frequency broadband compact acoustic structures, and has certain reference value for low-frequency broadband noise control.
General relativity in a nutshell I
Authors: Pinochet Jorge
Published: November 2023

Einstein’s general relativity is the best available theory of gravity. In recent years, spectacular proofs of Einstein’s theory have been conducted, which have aroused interest that goes far beyond the narrow circle of specialists. The aim of this work is to offer an elementary introduction to general relativity. In this first part, we introduce the geometric concepts that constitute the basis of Einstein’s theory. In the second part we will use these concepts to explore the curved spacetime geometry of general relativity.
Model-independent reconstruction of the interacting dark energy kernel: Binned and Gaussian process
Authors: Escamilla Luis A. , Akarsu Özgür , Di Valentino Eleonora , Vazquez J. Alberto
Published: November 2023

The cosmological dark sector remains an enigma, offering numerous possibilities for exploration.
One particularly intriguing option is the (non-minimal) interaction scenario between dark matter and dark energy. In this paper, to investigate this scenario, we have implemented Binned and Gaussian model-independent
reconstructions for the interaction kernel alongside the equation of state; while using data from BAOs,
Pantheon+ and Cosmic Chronometers.
In addition to the reconstruction process, we conducted a model selection to analyze how our
methodology performed against the standard ΛCDM model. The results revealed a slight indication, of at least 1σ confidence level, for some oscillatory dynamics in the interaction kernel and, as a by-product, also in the DE and DM. A consequence of this outcome is the possibility of a sign change in the direction of the energy transfer between DE and DM and a possible transition from a negative DE energy density in early-times to a positive one at late-times.

While our reconstructions provided a better fit to the data compared to the standard model, the Bayesian
Evidence showed an intrinsic penalization due to the extra degrees of freedom.
Nevertheless these reconstructions could be used as a basis for other physical models with lower
complexity but similar behavior.
Chaos in a tunneling universe
Authors: Bojowald Martin , Gluckman Ari
Published: November 2023

A recent quasiclassical description of a tunneling universe model is
shown to exhibit chaotic dynamics by an analysis of fractal dimensions in the
plane of initial values. This result relies on non-adiabatic features of the
quantum dynamics, captured by new quasiclassical methods. Chaotic dynamics in
the early universe, described by such models, implies that a larger set of
initial values of an expanding branch can be probed.
Effect of electron–electron interaction on polarization process of exciton and biexciton in conjugated polymer
Authors: Li 李 Xiao-Xue 晓雪 , Peng 彭 Hua 华 , Wang 王 Dong 栋 , Hou 侯 Dong 栋
Published: November 2023

By using one-dimensional tight-binding model modified to include electron–electric field interaction and electron–electron interaction, we theoretically explore the polarization process of exciton and biexciton in cis-polyacetylene. The dynamical simulation is performed by adopting the non-adiabatic evolution approach. The results show that under the effect of moderate electric field, when the strength of electron–electron interaction is weak, the singlet exciton is stable but its polarization presents obvious oscillation. With the enhancement of interaction, it is dissociated into polaron pairs, the spin-flip of which can be observed through modulating the interaction strength. For the triplet exciton, the strong electron–electron interaction restrains its normal polarization, but it is still stable. In the case of biexciton, the strong electron–electron interaction not only dissociate it, but also flip its charge distribution. The yield of the possible states formed after the dissociation of exciton and biexciton is also calculated.
Evolution of N = 20, 28, 50 shell closures in the 20 ≤ Z ≤ 30 region in deformed relativistic Hartree-Bogoliubov theory in continuum*
Authors: Zheng 郑 Ru-You 茹尤 , Sun 孙 Xiang-Xiang 向向 , Shen 申 Guo-fang 国防 , Geng 耿 Li-Sheng 立升
Published: November 2023

Magicity, or shell closure, plays an important role in our understanding of complex nuclear phenomena. In this work, we employ one of the state-of-the-art density functional theories, the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) with the density functional PC-PK1, to investigate the evolution of the

shell closures in the

region. We show how these three conventional shell closures evolve from the proton drip line to the neutron drip line by studying the charge radii, two-neutron separation energies, two-neutron gaps, quadrupole deformations, and single-particle levels. In particular, we find that in the

region, the

shell closure disappears or becomes quenched, mainly due to the deformation effects. Similarly, both experimental data and theoretical predictions indicate that the

shell closure disappears in the Mn isotopic chain, mainly due to the deformation effects. The DRHBc theory predicts the existence of the

shell closure in the Ca, Sc, and Ti isotopic chains, but the existing data for the Ti isotopes suggest the contrary, and therefore further research is needed.
Overview of tritium retention in divertor tiles and dust particles from the JET tokamak with the ITER-like wall
Authors: Torikai Y. , Kikuchi G. , Owada A. , Masuzaki S. , Otsuka T. , Ashikawa N. , Yajima M. , Tokitani M. , Oya Y. , Lee S.E. , Hatano Y. , Asakura N. , Hayashi T. , Oyaidzu M. , Likonen J. , Widdowson A. , Rubel M. ,   JET Contributors
Published: November 2023

Divertor tiles after Joint European Torus-ITER like wall (JET-ILW) campaigns and dust collected after JET-C and JET-ILW operation were examined by a set of complementary techniques (full combustion and radiography) to determine the total, specific and areal tritium activities, poloidal tritium distribution in the divertor and the presence of that isotope in individual dust particles. In the divertor tiles, the majority of tritium is detected in the surface region and, the areal activities in the ILW divertor are in the 0.5–12 kBq cm−2 range. The activity in the ILW dust is associated mainly with the presence of carbon particles being a legacy from the JET-C operation. The total tritium activities show significant differences between the JET operation with ILW and the earlier phase with the carbon wall (JET-C) indicating that tritium retention has been significantly decreased in the operation with ILW.
Characterization of a 220Rn source for low-energy electronic recoil calibration of the XENONnT detector
Authors: Jörg Florian , Li Shengchao , Schreiner Jochen , Simgen Hardy , Lang Rafael F.
Published: November 2023

Low-background liquid xenon detectors are utilized in the
investigation of rare events, including dark matter and neutrinoless
double beta decay. For their calibration, gaseous 220Rn can be
used. After being introduced into the xenon, its progeny isotope
212Pb induces homogeneously distributed, low-energy
(<30 keV) electronic recoil interactions. We report on the
characterization of such a source for use in the XENONnT
experiment. It consists of four commercially available 228Th
sources with an activity of 55 kBq. These sources provide a high
220Rn emanation rate of about 8 kBq. We find no indication for
the release of the long-lived 228Th above 1.7 mBq. Though an
unexpected 222Rn emanation rate of about 3.6 mBq is observed,
this source is still in line with the requirements for the XENONnT
experiment.