bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat transfer analysis for magnetohydrodynamic peristalsis of Reiner–Philippoff fluid: Application of an artificial neural network
Authors: Iqbal J. , Abbasi F. M. , Ali I.
Published: April 2024

Present communication explores a novel application of the computational intelligence technique, namely, the Levenberg–Marquardt scheme under a Backpropagated Neural Network (LM-BNN) to solve the mathematical model for the magnetohydrodynamic peristaltic transport of Reiner–Philippoff (R–Ph) pseudoplastic fluid considering the influences of Ohmic heating, mixed convection, and viscous dissipation through a symmetric channel. The R–Ph fluid model is used in this investigation to elucidate the non-Newtonian behavior of the fluid under consideration. The Reiner–Philippoff fluid model delineates the intricate relationship between stress and deformation rate within the fluid. There are a few studies available on the peristaltic transport of the Reiner–Philippoff fluid that do not incorporate Joule heating, mixed convection, and magnetic field effects. Therefore, a novel mathematical model is developed to employ an artificial neural network technique with a different approach that has not been examined before. The governing equations of the problem are simplified using long wavelength and low Reynolds number approximations, and the resulting system is numerically solved using the BVP4c scheme in MATLAB based on the shooting algorithm. Furthermore, a dataset is constructed through the BVP4c technique for the proposed LM-BNN, considering eight scenarios of peristaltic motion of the Reiner–Philippoff fluid model by varying the Bingham number, the Brinkman number, the Grashof number, the R–Ph fluid parameter, and the Hartmann number. The numerical dataset is divided into 15% for testing, 15% for training, and 70% for validation, which are utilized in LM-BNN to analyze the numerical solutions and Levenberg–Marquardt neural networks (LM-NNs) predicted results. The consistency and effectiveness of LM-BNN are validated through regression analysis, stresses at the wall, error histogram, correlation index, heat transfer, and mean squared error based fitness curves, which vary from 10−3→10−11. Variations in several flow parameters affecting temperature and velocity profiles are explained physically through graphs. Additionally, an analysis of heat transfer and stresses at the wall, including absolute errors, is provided through tables. The outcomes reveal that the improving Grashof number and the Hartmann number tend to increase the temperature profile. Tabular results indicate that rates of heat transfer improve when assigning higher values to the Hartmann number, the Brinkman number, and the Grashof number, whereas stresses at the wall decrease for the Reiner–Philippoff fluid parameter and the Bingham number. The error analysis of numerical simulations is a valuable step in determining whether the data obtained are reliable and accurate. In terms of absolute error, the disagreement between numerical solutions and those predicted by LM-NNs is approximately 10−5→10−11. It is clear from this error analysis that LM-NNs predicted results are consistent and reliable.
Investigation of cryogenic current–voltage anomalies in SiGe HBTs: Role of base–emitter junction inhomogeneities
Authors: Naik Nachiket R. , Gabritchidze Bekari , Chen Justin H. , Cleary Kieran A. , Kooi Jacob , Minnich Austin J.
Published: April 2024

The deviations of cryogenic collector current–voltage characteristics of SiGe heterojunction bipolar transistors (HBTs) from ideal drift-diffusion theory have been a topic of investigation for many years. Recent work indicates that direct tunneling across the base contributes to the non-ideal current in highly scaled devices. However, cryogenic discrepancies have been observed even in older-generation devices for which direct tunneling is negligible, suggesting that another mechanism may also contribute. Although similar non-ideal current–voltage characteristics have been observed in Schottky junctions and were attributed to a spatially inhomogeneous junction potential, this explanation has not been considered for SiGe HBTs. Here, we experimentally investigate this hypothesis by characterizing the collector current ideality factor and built-in potential of a SiGe HBT vs temperature using a cryogenic probe station. The temperature dependence of the ideality factor and the relation between the built-in potential as measured by capacitance–voltage and current–voltage characteristics are in good qualitative agreement with the predictions of a theory of electrical transport across a spatially inhomogeneous junction. These observations suggest that inhomogeneities in the base–emitter junction potential may contribute to the cryogenic non-idealities. This work helps to identify the physical mechanisms limiting the cryogenic microwave noise performance of SiGe HBTs.
Evolution of system connectivity to support food production in the Indus Basin in Pakistan
Authors: Siddiqi Afreen , Wescoat James L. , Selin Noelle E.
Published: April 2024

Sustainability challenges related to food production arise from multiple nature-society interactions occurring over long time periods. Traditional methods of quantitative analysis do not represent long-term changes in the networks of system components, including institutions and knowledge that affect system behavior. Here, we develop an approach to study system structure and evolution by combining a qualitative framework that represents sustainability-relevant human, technological, and environmental components, and their interactions, mediated by knowledge and institutions, with network modeling that enables quantitative metrics. We use this approach to examine the water and food system in the Punjab province of the Indus River Basin in Pakistan, exploring how food production has been sustained, despite high population growth, periodic floods, and frequent political and economic disruptions. Using network models of five periods spanning 75 y (1947 to 2022), we examine how quantitative metrics of network structure relate to observed sustainability-relevant outcomes and how potential interventions in the system affect these quantitative metrics. We find that the persistent centrality of some and evolving centrality of other key nodes, coupled with the increasing number and length of pathways connecting them, are associated with sustaining food production in the system over time. Our assessment of potential interventions shows that regulating groundwater pumping and phasing out fossil fuels alters network pathways, and helps identify potential vulnerabilities for future food production.
Mortality and morbidity ramifications of proposed retractions in healthcare coverage for the United States
Authors: Pandey Abhishek , Fitzpatrick Meagan C. , Singer Burton H. , Galvani Alison P.
Published: April 2024

In the absence of universal healthcare in the United States, federal programs of Medicaid and Medicare are vital to providing healthcare coverage for low-income households and elderly individuals, respectively. However, both programs are under threat, with either enacted or proposed retractions. Specifically, raising Medicare age eligibility and the addition of work requirements for Medicaid qualification have been proposed, while termination of continuous enrollment for Medicaid was recently effectuated. Here, we assess the potential impact on mortality and morbidity resulting from these policy changes. Our findings indicate that the policy change to Medicare would lead to over 17,000 additional deaths among individuals aged 65 to 67 and those to Medicaid would lead to more than 8,000 deaths among those under the age of 65. To illustrate the implications for morbidity, we further consider a case study among those people with diabetes who would be likely to lose their health insurance under the policy changes. We project that these insurance retractions would lead to the loss of coverage for over 700,000 individuals with diabetes, including more than 200,000 who rely on insulin.
Evolutionarily conserved neural responses to affective touch in monkeys transcend consciousness and change with age
Authors: Charbonneau Joey A. , Santistevan Anthony C. , Raven Erika P. , Bennett Jeffrey L. , Russ Brian E. , Bliss-Moreau Eliza
Published: April 2024

Affective touch—a slow, gentle, and pleasant form of touch—activates a different neural network than which is activated during discriminative touch in humans. Affective touch perception is enabled by specialized low-threshold mechanoreceptors in the skin with unmyelinated fibers called C tactile (CT) afferents. These CT afferents are conserved across mammalian species, including macaque monkeys. However, it is unknown whether the neural representation of affective touch is the same across species and whether affective touch’s capacity to activate the hubs of the brain that compute socioaffective information requires conscious perception. Here, we used functional MRI to assess the preferential activation of neural hubs by slow (affective) vs. fast (discriminative) touch in anesthetized rhesus monkeys (Macaca mulatta). The insula, anterior cingulate cortex (ACC), amygdala, and secondary somatosensory cortex were all significantly more active during slow touch relative to fast touch, suggesting homologous activation of the interoceptive-allostatic network across primate species during affective touch. Further, we found that neural responses to affective vs. discriminative touch in the insula and ACC (the primary cortical hubs for interoceptive processing) changed significantly with age. Insula and ACC in younger animals differentiated between slow and fast touch, while activity was comparable between conditions for aged monkeys (equivalent to >70 y in humans). These results, together with prior studies establishing conserved peripheral nervous system mechanisms of affective touch transduction, suggest that neural responses to affective touch are evolutionarily conserved in monkeys, significantly impacted in old age, and do not necessitate conscious experience of touch.
Calcium ions promote migrasome formation via Synaptotagmin-1
Authors: Han Yiyang , Yu Li
Published: April 2024

Migrasomes, organelles crucial for cell communication, undergo distinct stages of nucleation, maturation, and expansion. The regulatory mechanisms of migrasome formation, particularly through biological cues, remain largely unexplored. This study reveals that calcium is essential for migrasome formation. Furthermore, we identify that Synaptotagmin-1 (Syt1), a well-known calcium sensor, is not only enriched in migrasomes but also indispensable for their formation. The calcium-binding ability of Syt1 is key to initiating migrasome formation. The recruitment of Syt1 to migrasome formation sites (MFS) triggers the swelling of MFS into unstable precursors, which are subsequently stabilized through the sequential recruitment of tetraspanins. Our findings reveal how calcium regulates migrasome formation and propose a sequential interaction model involving Syt1 and Tetraspanins in the formation and stabilization of migrasomes.
APMP key comparison of AC-DC current transfer standards: final report
Authors: Jing Dr T , Hagen Mr Thomas , Yang Dr Steven , Fujiki Dr Hiroyuki , Lee Dr Hyung-Kew , Jiangtao Dr Zhang , Golovins Dr Eugene , Kumtawee Mr Chalit , Ibrahim Dr Muhammad Azwan Bin , Tsai Ms Hsiu-Ju
Published: April 2024

Main text

This report summarizes the results and performances of APMP.EM-K12, APMP key comparison of AC-DC current transfer standards of 10 mA and 5 A at frequencies of 10 Hz, 55 Hz, 1 kHz, 10 kHz, 20 kHz, 50 kHz, and 100 kHz. Ten National Metrology Institutes participated in this key comparison, including NMC/A*STAR (Singapore, pilot Laboratory), NMIA (Australia), SCL (Hong Kong, China), NMIJ (Japan), KRISS (Rep of Korea), NIM (China), NMISA (South Africa), NIMT (Thailand), NMIM (Malaysia), and CMS/ITRI (Chinese Taipei). The key comparison is linked to the CCEM one, CCCEM-K12, with same measurement quantities through the performances of two laboratories, NMC and NMIA, in both key comparisons. The degrees of equivalence of individual participating laboratories with the reference values of CCEM-K12 were thus concluded in this report.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Report of subsequent key comparison CCQM - K73.2018.2 amount content of H+ in hydrochloric acid (0.1 mol/kg-1)
Authors: Máriássy Michal , Hanková Zuzana , Petrenko Anton , Melnykov Oleksandr , Melnyk Volodymyr , Lameko Oleksandr , Borges Paulo Paschoal , Sobral Sidney Pereira
Published: April 2024

Main text

The subsequent key comparison K73.2018.2 was performed to demonstrate the capability of the participating institutes to measure the amount content of H+ in hydrochloric acid as a follow-up of the previous key comparison CCQM-K73.2018. A HCl solution of a slightly different composition to that in CCQM-K73.2018 was used.

There were two institutes and SMU as the coordinating laboratory participating in this subsequent comparison. UkrCSM obtained results in good agreement with the reference value; INMETRO results exhibited a large bias due to a calculation error found only after disclosure of the results.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
How the spherical modes of gravitational waves can be detected despite only seeing one ray
Authors: Torres-Orjuela Alejandro
Published: April 2024

The spherical modes of gravitational waves (GWs) have become a major focus of recent detection campaigns due to the additional information they can provide about different properties of the source. However, GW detection is restricted to only detecting one ray and hence it is not obvious how we can extract information about angular properties. In this note, we introduce a new gauge that makes visible GW detection does not only contain information on the second time derivative but also on the angular derivatives of the GW. In particular, we show that the angular derivatives are of the same order as the time derivatives of the wave thus allowing us to constrain the spherical modes. To further illustrate the detection of the spherical modes, we discuss how the evolution of the orbit of the source and thus the phase of the wave depends on them.
A residual fully convolutional network (Res-FCN) for electromagnetic inversion of high contrast scatterers at an arbitrary frequency within a wide frequency band
Authors: Hu Hao-Jie , Li Jiawen , Xiao Li-Ye , Cheng Yu , Liu Qing Huo
Published: April 2024

Many successful machine learning methods have been developed for electromagnetic (EM) inverse scattering problems. However, so far, their inversion has been performed only at the specifically trained frequencies. To make the machine learning based inversion method more generalizable for realistic engineering applications, this work proposes a residual fully convolutional network (Res-FCN) to perform EM inversion of high contrast scatterers at an arbitrary frequency within a wide frequency band. The proposed Res-FCN combines the advantages of the Res-Net and the fully convolutional network (FCN). Res-FCN consists of an encoder and a decoder: the encoder is employed to extract high-dimensional features from the measured scattered field through the residual frameworks, while the decoder is employed to map from the high-dimensional features extracted by the encoder to the electrical parameter distribution in the inversion region by the up-sample layer and the residual frameworks. Four numerical examples verify that the proposed Res-FCN can achieve good performance in the 2D EM inversion problem for high contrast scatterers with anti-noise ability at an arbitrary frequency point within a wide frequency band.
Research on the stress magnetic coupling effect of a permalloy based on an optimized Jiles Atherton model in magnetic shielding devices
Authors: Sun Jinji , Ren Jianyi , Zhou Weiyong , Jiang Qian , Wang Pengfei , Sai Ting , Tang Jiqiang , Ye Jing
Published: April 2024

Magnetic shielding devices are extensively used in the measurement of quantum physics, the static magnetic field shielding layer made of permalloy in the magnetic shielding device will work under different stresses. Due to the magnetic properties of permalloy being sensitive to the applied stress, it is necessary to establish a magnetic property model considering stress to accurately evaluate the residual magnetic field in magnetic shielding devices under different stresses. However, the measurement and modeling of the magnetic properties of permalloy under different stresses have not been considered in relevant research. In this paper, the magnetic properties of permalloy under different tensile and compressive stresses were measured, and the optimized Jiles Atherton (JA) model of permalloy considering stress constructed. The parameters of the JA model are extracted by a genetic algorithm,-the particle swarm optimization algorithm, through measurement. Finally, the effectiveness of the model in predicting magnetic properties is validated. The JA optimization model considering stress can improve the calculation accuracy of magnetic shielding devices, which is of great significance for the design and application of magnetic shielding devices.
A dynamic phase separation model for glass transition behavior in water-triggered shape memory polymer towards programmable recovery onset
Authors: Shi Jiabin , Lu Haibao , Zheng Tengfei , Fu Yong-Qing
Published: April 2024

Water-triggered shape memory polymers (SMPs) have been extensively studied for biomedical applications due to their advantages of non-thermal actuation capability. However, few studies have been carried out to explore the working principle of shape recovery onset, which is essentially determined by the complex reactions between polymer macromolecules and water molecules. In this study, we developed a phase separation model to describe the dynamic glass transition in water-triggered SMPs. Based on the phase transition theory, dense and dilute phase separations of polymer macromolecules can be achieved when the dynamic diffusions of water molecules in the SMPs undergo dehydration and absorption processes, respectively. Then, the dynamic glass transition is resulted from the dehydration and absorption of water molecules, leading to the dense and dilute phases in the SMPs. Therefore, a free-energy equation has been developed to characterize the recovery onset, in which the mixing free energy and elastic free energy are originated from the Flory–Huggins solution theory and phase separation model, respectively. Moreover, the glass transition and its connection to shape recovery behaviors, i.e. recovery ratio, relaxation time and dynamic mechanical modulus, have also been investigated, according to the Fick’s diffusion law. Meanwhile, onset of programmable recovery has been explained by the dynamic phase separation, based on the transpiration theory and permeability model. Finally, the proposed model is verified using the experimental results reported in the literature. This study is expected to provide a fundamental approach to formulate the constitutive relationship between the dynamic phase separation and programmable recovery onset in the water-triggered SMPs.
Optimization of thermo-spin voltage in vertical nanostructures by geometrical means
Authors: Gao Fupeng , Hu Shaojie , Wang Dawei , Kimura Takashi
Published: April 2024

The thermo-spin conversion provides new concepts for further developing the green energy-harvesting technology because spin can be controlled with minimal energy in nanostructures. Through theoretical analysis of thermo-spin generation, transportation and conversion in ferromagnet/non-ferromagnet/heavy metal (FM/NM/HM) vertical structures, we found that the output transverse thermo-spin voltage is independent of the structure’s width, but varies linearly with the structure’s length. To validate our predictions, we fabricated the thermo-spin devices with a CoFeAl/Cu/Pt structure. Our results indicate that FM/NM/HM structures can be utilized to design flexible thermo-spin conversion devices.
Stacking-dependent interlayer magnetic interactions in CrSe2
Authors: Yang Xinlong , Xie Xiaoyang , Yang Wenqi , Wang Xiaohui , Li Menglei , Zheng Fawei
Published: April 2024

Recently, CrSe2, a new ferromagnetic van der Waals two-dimensional material, was discovered to be highly stable under ambient conditions, making it an attractive candidate for fundamental research and potential device applications. Here, we study the interlayer interactions of bilayer CrSe2 using first-principles calculations. We demonstrate that the interlayer interaction depends on the stacking structure. The AA and AB stackings exhibit antiferromagnetic (AFM) interlayer interactions, while the AC stacking exhibits ferromagnetic (FM) interlayer interaction. Furthermore, the interlayer interaction can be further tuned by tensile strain and charge doping. Specifically, under large tensile strain, most stacking structures exhibit FM interlayer interactions. Conversely, under heavy electron doping, all stacking structures exhibit AFM interlayer interactions. These findings are useful for designing spintronic devices based on CrSe2.
Ultra-broadband absorbance of nanometer-thin pyrolyzed-carbon film on silicon nitride membrane
Authors: Jorudas Justinas , Rehman Hamza , Cojocari Maria , Pashnev Daniil , Urbanowicz Andrzej , Kašalynas Irmantas , Bertoni Benedetta , Vicarelli Leonardo , Pitanti Alessandro , Malykhin Sergei , Svirko Yuri , Kuzhir Polina , Fedorov Georgy
Published: April 2024

Fifty percents absorption by thin film, with thickness is much smaller than the skin depth and optical thickness much smaller than the wavelength, is a well-known concept of classical electrodynamics. This is a valuable feature that has been numerously widely explored for metal films, while chemically inert nanomembranes are a real fabrication challenge. Here we report the 20 nm thin pyrolyzed carbon film (PyC) placed on 300 nm thick silicon nitride (Si3N4) membrane demonstrating an efficient broadband absorption in the terahertz and near infrared ranges. While the bare Si3N4 membrane is completely transparent in the THz range, the 20 nm thick PyC layer increases the absorption of the PyC coated Si3N4 membrane to 40%. The reflection and transmission spectra in the near infrared region reveal that the PyC film absorption persists to a level of at least 10% of the incident power. Such a broadband absorption of the PyC film opens new pathways toward broadband bolometric radiation detectors.
Silver nanowires/waterborne polyurethane composite film based piezoresistive pressure sensor for ultrasensitive human motion monitoring
Authors: Zhang Chengshe , Zhou Yimin , Ye Cui
Published: April 2024

Flexible piezoresistive pressure sensors are gaining significant attention, particularly in the realm of flexible wearable electronic skin. Here, a flexible piezoresistive pressure sensor was developed with a broad sensing range and high sensitivity. We achieved this by curing polydimethylsiloxane (PDMS) on sandpaper, creating a PDMS film as the template with a micro-protrusion structure. The core sensing layer was formed using a composite of silver nanowires (AgNWs) and waterborne polyurethane (WPU) with a similar micro-protrusion structure. The sensor stands out with its exceptional sensitivity, showing a value of 1.04 × 106 kPa−1 with a wide linear range from 0 to 27 kPa. It also boasts a swift response and recovery time of 160 ms, coupled with a low detection threshold of 17 Pa. Even after undergoing more than 1000 cycles, the sensor continues to deliver stable performance. The flexible piezoresistive pressure sensor based on AgNWs/WPU composite film (AWCF) can detect small pressure changes such as pulse, swallowing, etc, which indicates that the sensor has great application potential in monitoring human movement and flexible wearable electronic skin.
A note on cascade flux laws for the stochastically-driven nonlinear Schrödinger equation
Authors: Bedrossian Jacob
Published: April 2024

In this note we point out some simple sufficient (plausible) conditions for ‘turbulence’ cascades in suitable limits of damped, stochastically-driven nonlinear Schrödinger equation in a d-dimensional periodic box. Simple characterizations of dissipation anomalies for the wave action and kinetic energy in rough analogy with those that arise for fully developed turbulence in the 2D Navier–Stokes equations are given and sufficient conditions are given which differentiate between a ‘weak’ turbulence regime and a ‘strong’ turbulence regime. The proofs are relatively straightforward once the statements are identified, but we hope that it might be useful for thinking about mathematically precise formulations of the statistically-stationary wave turbulence problem.
TIST-Net: style transfer in dynamic contrast enhanced MRI using spatial and temporal information
Authors: Tattersall Adam G , Goatman Keith A , Kershaw Lucy E , Semple Scott I K , Dahdouh Sonia
Published: April 2024

Objective. Training deep learning models for image registration or segmentation of dynamic contrast enhanced (DCE) MRI data is challenging. This is mainly due to the wide variations in contrast enhancement within and between patients. To train a model effectively, a large dataset is needed, but acquiring it is expensive and time consuming. Instead, style transfer can be used to generate new images from existing images. In this study, our objective is to develop a style transfer method that incorporates spatio-temporal information to either add or remove contrast enhancement from an existing image. Approach. We propose a temporal image-to-image style transfer network (TIST-Net), consisting of an auto-encoder combined with convolutional long short-term memory networks. This enables disentanglement of the content and style latent spaces of the time series data, using spatio-temporal information to learn and predict key structures. To generate new images, we use deformable and adaptive convolutions which allow fine grained control over the combination of the content and style latent spaces. We evaluate our method, using popular metrics and a previously proposed contrast weighted structural similarity index measure. We also perform a clinical evaluation, where experts are asked to rank images generated by multiple methods. Main Results. Our model achieves state-of-the-art performance on three datasets (kidney, prostate and uterus) achieving an SSIM of 0.91 ± 0.03, 0.73 ± 0.04, 0.88 ± 0.04 respectively when performing style transfer between a non-enhanced image and a contrast-enhanced image. Similarly, SSIM results for style transfer from a contrast-enhanced image to a non-enhanced image were 0.89 ± 0.03, 0.82 ± 0.03, 0.87 ± 0.03. In the clinical evaluation, our method was ranked consistently higher than other approaches. Significance. TIST-Net can be used to generate new DCE-MRI data from existing images. In future, this may improve models for tasks such as image registration or segmentation by allowing small training datasets to be expanded.
Carrier mobility dependence of indium antimonide-bismide on carrier concentration, temperature, and bismuth composition grown on semi-insulating gallium arsenide substrate
Authors: Loke Wan Khai , Tan Kian Hua , Wicaksono Satrio , Yoon Soon Fatt
Published: April 2024

We explore the impact of carrier concentration, temperature, and bismuth (Bi) composition on the carrier mobility of indium antimonide-bismide (InSb1−x
Bi
x
) material. Utilizing the molecular beam epitaxy method, we achieved high Bi composition uniformity. This method also enables the InSb1−x
Bi
x
to be grown on semi-insulating GaAs substrate, effectively preventing parallel electrical conduction during Hall effect measurement. Our findings reveal that InSb1−x
Bi
x
doped with silicon (Si) and tellurium (Te) consistently exhibit n-type conductivity. In contrast, InSb1−x
Bi
x
doped with beryllium (Be) exhibit a transition from n to p type conductivity, subjected to the Be doping level and the measurement temperature. Based on these observations, we proposed an empirical model describing the dependence of InSb1−x
Bi
x
electron mobility on carrier concentration, temperature, and Bi composition, specifically for Si and Te-doped InSb1−x
Bi
x
samples. These insights gained from this study hold potential application in photodetector device simulations.
Fabrication of plasmonic junction diodes based on Ag@ZnO core-shell nanostructures
Authors: Erdogan Erman , Canpolat Nurtac , Aydogan Sakir , Yilmaz Mehmet
Published: April 2024

In this study, Ag nanoparticles and Ag@ZnO core–shell nanostructures were prepared using the wet chemical method and these nanostructures were used for Ag@ZnO/p-Si diode fabrication. Structural, morphological, and optical characterization techniques were applied for Ag@ZnO core–shell NPs prepared by using different molarity of precursor ZnCl2 (10 mM, 20 mM, 30 mM) and showed that the effect of increasing precursor amount on these physical properties of nanoparticles is important. For Ag@ZnO, transmission electron microscopy shows an average diameter of Ag nanoparticles was 51.32 nm and Ag@ZnO core–shell nanostructures were found to be between 31 and 92 nm. The UV-visible absorbance also shows significant plasmonic resonance for NPs, with a slight red shift increasing precursor molarity. The peaks are found to be from 412 nm to 432 nm. This redshift in surface plasmon absorption of Ag@ZnO core–shell structures are consistent with XPS survey. The current–voltage (I-V) characteristic curves of heterojunction diodes were taken in the dark and at room temperature, and it was observed that they showed a rectifying feature. Ideality factor and barrier height values have been found between 2.14 and 3.87, and 0.56 and 0.78, respectively. The results revealed that Ag@ZnO was successfully synthesized and can be used in rectification applications.
On the renormalisation group, protein folding, and naturalness
Authors: Patrascu Andrei T
Published: April 2024

I am showing how the ideas behind the renormalisation group can be generalised in order to produce the desired reduction in the degrees of freedom, other that the ones considered up to now. Instead of looking only at the renormalisation group flow, inspiration from optimisation tools for regulators of truncated theories is used to show that there exists another mathematical structure, in the morphisms between various renormalisation groups, characterised by their operations, encoded by means of various regularisation functions. This expands the idea of renormalisation group to a renormalisation category. A group structure exists at the level of those morphisms, leading to new information emerging in the flowing process. Impact on problems like the naturalness and protein folding is being presented briefly.
Transmission in graphene through a double laser barrier
Authors: El Aitouni Rachid , Mekkaoui Miloud , Jellal Ahmed
Published: April 2024

We study the tunneling behavior of Dirac fermions in graphene subjected to a double barrier potential profile created by spatially overlapping laser fields. By modulating the graphene sheet with an oscillating structure formed from two laser barriers, we aim to understand how the transmission of Dirac fermions is influenced by such a light-induced electric potential landscape. Using the Floquet method, we determine the eigenspinors of the five regions defined by the barriers applied to the graphene sheet. Applying the continuity of the eigenspinors at barrier edges and using the transfer matrix method, we establish the transmission coefficients. These allow us to show that oscillating laser fields generate multiple transmission modes, including zero-photon transmission aligned with the central band ε and photon-assisted transmission at sidebands ε + l
ϖ, with l = 0, ± 1, ⋯ and frequency ϖ. For numerical purposes, our attention is specifically directed towards transmissions related to zero-photon processes (l = 0), along with processes involving photon emission (l = 1) and absorption (l = − 1). We find that transmission occurs only when the incident energy is above the threshold energy ε > k

y
+ 2ϖ, with transverse wave vector k

y
. We find that the variation in distance d

1

separating two barriers of widths
d
2 − d
1 suppresses one transmission mode. Additionally, we show that an increase in laser intensity modifies transmission sharpness and amplitude.
Integrated study of the structural and magnetic characteristics of Nd(Mn, Cr)0.5O3: exploring perovskite material
Authors: Altowairqi Yasir , Shariq Mohammad , Alasmari Aeshah , Alshehri Khairiah , Alayyafi AbdulAziz A , Alzahrani Ali , Akermi Mehdi , Ali Syed Kashif , Khan Mohd Shakir , Abdul Azeez Noorjahan
Published: April 2024

In this work, a perovskite material, Nd(Mn,Cr)0.5O3, is synthesized by a sol–gel chemical route method, and the structural and magnetic properties of the prepared samples were studied for a range of annealing temperatures. The variation of structural parameters against annealing temperatures is analyzed via Rietveld refinement, and it exhibits orthorhombic cubic geometry with non-monotonically increasing lattice parameters. lattice strain is due to canting in the Cr3+ and Mn3+ ions and the presence of strain is also confirmed by the shifting of XRD peaks towards a higher 2θ angle. The obtained Goldschmidt tolerance factor is 0.87, which confirms the stability of the perovskite structure. The magnetic properties of the prepared samples show the ferromagnetic transition temperature ranging from 86.5 K to 82.2 K due to super-exchange interaction between Cr3+ and Mn3+ ions via oxygen ions. The stability in crystal structure, lower value of strain, and ferromagnetic nature at low temperature for the samples annealed up to1000 °C may make this material applicable for magnetic data storage.
BD-YOLO: detection algorithm for high-resolution remote sensing images
Authors: Lou Haitong , Liu Xingchen , Bi Lingyun , Liu Haiying , Guo Junmei
Published: April 2024

This paper focuses on detecting extremely small targets in aerial images. Compared to common datasets, the average size of targets in remote sensing images is only 12.8 pixels, significantly smaller than those in common datasets. Therefore, directly applying existing detectors to aerial images is ineffective. To address this issue and ensure real-time performance, This paper propose BD-YOLO, which incorporates five key innovations. A dual Backbone route was proposed to maintain data integrity and achieve high-resolution aerial remote sensing detection. Additionally, a new feature fusion method was developed to comprehensively merge shallow and deep information. To supplement small-sized target information, a new network structure was proposed. The detector strategy used by BD-YOLO considers the detection accuracy of objects with different sizes. Furthermore, a lightweight method was adopted to ensure real-time performance of the algorithm. BD-YOLO outperformed YOLOv8s on the AI-TOD dataset, achieving a higher mAP by 2.4%. Similarly, on the Visdrone dataset, BD-YOLO achieved a 2.5% higher mAP compared to YOLOv8s. Additionally, on the Tinyperson dataset, BD-YOLO achieved a 0.6% higher mAP than YOLOv8s. Notably, BD-YOLO maintains real-time performance while ensuring accurate object detection.
Exploring the Mn doped BaTe alloy for spintronics and energy harvesting applications
Authors: Saleem Sanam , Yaseen Muhammad , Aldaghfag Shatha A , Dahshan A , Kazim Muhammad Zafarullah , Nasarullah
Published: April 2024

In the present study, the ferromagnetic semiconductor behavior of Mn doped BaTe is reported along with their physical properties. The calculations are done by full potential linearized augmented plane wave (FP-LAPW) approach within spin-polarized density functional theory (SP-DFT). Formation energies were computed to satisfy the stability of reported alloys. The spin-polarization is included in the calculations to study the electronic (band structure (BS), density of states (DOS)) and magnetic characteristics. Ba1−xMnxTe elucidates the magnetic semiconductor nature with direct band gap (Eg) in both spin channels while indirect Eg (1.66 eV) is observed for pure BaTe compound. Stable ferromagnetic (FM) states are vindicated owing to the p-d hybridization which are contributors in inducing magnetic moments (μ
B) at interstitial and non-magnetic sites. The optical parameters (reflectivity, absorption coefficient, refraction, optical conductivity and dielectric function) were computed within an energy range of 0–10 eV. Thermoelectric (TE) features are also figured using Boltaz-Trap code in terms of thermal and electrical conductivity, figure of merit, Seebeck coefficient and power factor. The analysis of optical parameters suggests that the considered alloys is active within visible to UV-range, having potential applications in optoelectronic, photovoltaic and thermoelectric applications.
Exploring Intertwined quantum and cryogenic behaviour in ultra-scaled 10 nm MOSFET: a NEGF quantum ballistic simulation
Authors: Anam Aadil , Amin S Intekhab , Prasad Dinesh
Published: April 2024

Silicon-based spin qubits have emerged as promising candidates for scalable quantum information processing. This study first time investigates the behaviour of ultra-scaled 10 nm gate length and 3 nm channel thickness nanoscale double gate metal-oxide semiconductor field-effect transistors (MOSFETs) over a broad temperature range, from deep cryogenic (4 K) to room temperature (300 K). Employing the Non-Equilibrium Green’s Function (NEGF) method, the research explores the intertwined quantum and cryogenic behaviours of the various quantum phenomena, including eigen energies, eigen-functions, electron concentration, current characteristics, and more. This comprehensive analysis sheds light on the intricate interplay of quantum effects in nanoscale transistors under deep cryogenic conditions, offering valuable insights into the development of cryo-CMOS circuits for quantum computing.
Erratum: Improved treatment of dark Matter capture in neutron stars III: nucleon and exotic targets
Authors: Anzuini Filippo , Bell Nicole F. , Busoni Giorgio , Motta Theo F. , Robles Sandra , Thomas Anthony W. , Virgato Michael
Published: April 2024

In this erratum we revise the results presented in our published paper, which made use of
an incorrect expression for the nucleon matrix elements. Using the correct expression, the
significance of our results are increased by up to an order of magnitude. Specifically, we find
that nucleon structure and strong interactions suppress the rate at which dark matter is captured
by up to four orders of magnitude for heavy neutron stars. The cross sections for which the
capture rate saturates the geometric limit are increased accordingly. Our qualitative conclusions
are unchanged.
An encrypted hiding scheme for 3D objects based on CGH and Henon mapping
Authors: Ji Xiangxiang , Xi Sixing , Yu Nana , Liu Songxiao , Yuan Hao , Wang Xiaolei , Lang Liying
Published: April 2024

A method is proposed to enhance the security of three-dimensional (3D) objects through computer-generated hologram (CGH) encryption and hiding. The process begins by encoding the 3D object using an iterative angular-spectrum layer-oriented method to create an optimized phase-only CGH. Next, the encrypted image is produced by modulating the phase-only CGH with a chaotic random phase mask (CRPM) generated through Henon mapping. Subsequently, a combination of discrete wavelet transform (DWT) and singular value decomposition (SVD) is utilized to embed the encrypted data into a visually secure image, ensuring the encryption and concealment of 3D objects. During decryption, the accurate decryption procedure and keys must be applied to achieve the final reconstruction. The utilization of CGH in conjunction with CRPM effectively enhances the security of 3D objects, while the integration of DWT and SVD ensures the visual security properties of the encrypted data, providing a dual layer of protection for 3D objects. Experimental simulation results demonstrate that this approach achieves high-security encryption and concealment of 3D objects, ensuring high-quality decryption of 3D objects during the reconstruction process.
171st-order harmonic soliton erbium-doped fiber laser based on 2H-MoTe2 saturable absorber
Authors: Liu Hai-Yan , Zhang Ze-Xin , Xv Lu-Feng , Tian Jin-Rong , Song Yan-Rong
Published: April 2024

We have demonstrated a high order harmonic mode-locked erbium-doped fiber laser by utilizing 2H-MoTe2 film as a saturable absorber (SA). The SA is synthesized by depositing 2H-MoTe2 film on a D-shaped fiber. The nonlinear optical properties of the 2H-MoTe2 SA are characterized, showing a modulation depth of 14.7% and a saturation intensity of 3 GW cm−2. Through optimizing the pump power and intra-cavity polarization state, a 171st-order harmonic soliton at 0.9 GHz repetition frequency with a pulse width of 1.06 ps was obtained. The fundamentally mode-locked pulse train had a pulse width of 1.03 ps and a repetition rate of 5.33 MHz. To the best of our knowledge, the 171st-order harmonic soliton is the highest operating repetition frequency that has ever been demonstrated in a 2H-MoTe2 SA mode locked fiber laser. The results indicate the potential of 2H-MoTe2 SA at high repetition rates regimes, which could benefit for future possible application.
Study of Secondary Cosmic Rays and Astronomical X-Ray Sources using Small Stratospheric Balloons
Authors: Sikdar Rupnath , Chakrabarti Sandip K. , Bhowmick Debashis
Published: April 2024

The X-ray sources of the universe are extraterrestrial in nature which emit X-ray photons. The closest strong X-ray source is the Sun, which is followed by various compact sources such as neutron stars, black holes, the Crab pulsar, etc. In this paper, we analyze the data received from several low-cost lightweight meteorological balloon-borne missions launched by the Indian Centre for Space Physics. Our main interest is to study the variation of the vertical intensity of secondary cosmic rays, the detection of strong X-ray sources, and their spectra in the energy band of ∼10–80 keV during the complete flights. Due to the lack of an onboard pointing system, low exposure time, achieving a maximum altitude of only ∼42 km, and freely rotating the payload about its axis, we modeled the background radiation flux for the X-ray detector using physical assumptions. We also present the source detection method, observation of the pulsation of the Crab (∼33 Hz), and spectra of some sources such as the quiet Sun and the Crab pulsar.
Verification of drone formation relative positioning technology based on Beidou
Authors: Wan Xiang , Liu Tongqi , Wu Jiajia , Zhao Jian , Gong Yanyi , Miao Wei , Mao Liulei
Published: April 2024

High precision drone formation flight requires real-time knowledge of the three-dimensional position and velocity information of the carrier. The Beidou navigation system, due to its all-weather and high-precision characteristics, can provide good relative position results for drones. However, when drones move at high speeds and in complex environments, The Beidou navigation receiver may experience various errors, leading to poor positioning results or even inability to locate. This paper provides targeted technical design for the reliability of Beidou relative positioning in complex environments during drone flight, monitors navigation data in real time to improve the fixed reliability of overall ambiguity, and uses BeiDou signal simulator to simulate and generate observation data for analysis and processing. The test results show that this method improves the continuity and reliability of the fixed ambiguity of Beidou, and can meet the requirements of real-time formation flight of drone.
Multi-view Subspace Clustering Based on Weighted Tensor Schatten-P Norm
Authors: Zheng Shuxin , Zhang Yunjie , Peng Cuicui
Published: April 2024

In the era of advancing technology and continuous societal evolution, an abundance of voluminous data from various domains has become prevalent in the public domain. Managing this wealth of data necessitates a series of preprocessing procedures, encompassing tasks such as data storage, computation, and analysis, with the aim of unveiling intrinsic features and patterns contained within. Among these procedures, clustering stands out as a crucial step, with the primary goal of unveiling the hidden structures within the data and organizing data samples into meaningful clusters based on specific criteria. Early clustering efforts were based on a singleview. Real world data, however, often contains interrelated information, leading to the emergence of multi-view clustering. Multiview subspace clustering (T-SVD) has been widely used in recent years. However, the equal treatment of each singular value in this approach lacks relevance when the data is noisy or contaminated. In order to improve the robustness and clustering performance, this paper presents a T-SVD weighted tensor norm. In order to improve the robustness, a Schatten-P norm was proposed. This paper explores multi-view subspace clustering is based on the Schatten-P norm weighted tensor. Experiments are carried out on 6 benchmark data sets, and the results are compared with 4 existing ones. Experiments show that the proposed approach is better than the most advanced multi-view subspace clustering methods.
Drillability classification and identification for rock mass based on machine learning
Authors: Wu Yumeng , Wang Shaofeng
Published: April 2024

In order to better apply the drilling method to underground mines, rock drillability classification and identification in situ by drilling process monitoring technology is a convenient and effective method to achieve the rock mass drillability. In this study, a database was established based on 188 groups of drilling parameters, drillability parameters and rock mechanics parameters. By analyzing the correlation between mechanical parameters and drillability parameters, rock drillability was classified using the TOPSIS-RMR method. Then, drilling force (F), torque (T), rotation speed (N), rate of penetration (V), specific energy (SE) and drillability index (Id) were used as machine learning input variables to predict drillability grades. Finally, the machine learning classification models include SVM, ELM, BPNN, RBF, RF and LSTM are compared to select the optimal model. The efforts and results can be used to evaluate the rock mass drillability and provide support for the design optimization of drilling and blasting method. It can effectively protect the safety and improve efficiency of underground mining.
Study on bioleaching behavior of sphalerite from lead concentrate in agitator tank
Authors: Xue Liu , Jianzhi Sun , Shuang Liu , He Shang , Wencheng Gao , Xinlong Yang , Jiankang Wen , Bowei Chen
Published: April 2024

Sphalerite which is highly continuous with galena cannot be effectively separated by flotation, the extraction of zinc from sphalerite in bioleaching process has become an alternative method. By testing the initial iron concentration, pulp density, grinding fineness and other parameters as well as monitoring pH, potential and dissolved oxygen, the zinc content of the lead concentrate decreased from 8.41% to less than 1% after bioleaching in 8L agitator tank. The initial concentration of ferric is the most significant factor affecting the zinc extraction efficiency of sphalerite, and when the concentration of ferric ions reaches 9g/L, acceptable leaching yield can be achieved.