bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical and simulation analysis of the measurement of polarized fluid flow in a circular pipe with electric field excitation
Authors: Vadde Anusha , Kadambi Govind R , C Siddabasappa 
Published: April 2023

Abstract
Measurement of conductive fluid flow velocity is essential in applications such as measuring the velocity of water flow in the agriculture sector, sewage water treatment plants, and metal refining industries. This paper proposes a contactless flow measurement device for computing the flow velocity of conductive fluids based on movement of polarized fluid flow. The proposed simulation model of the flow meter can also determine the conductivity of the fluid for varying flow velocity. The obtained simulated results concur with the earlier theoretical studies. Based on the interpretations in the underlying assumptions and physics of a fluid flow under a source of an electric field, it reveals that it is possible to measure a flow velocity of 0.01–10 m s−1 for conductive fluids of 0.1–10 S m−1.
A computational building block approach towards multiscale architected materials analysis and design with application to hierarchical metal metamaterials
Authors: Buehler Markus J 
Published: April 2023

Abstract
In this study we report a computational approach towards multiscale architected materials analysis and design. A particular challenge in modeling and simulation of materials, and especially the development of hierarchical design approaches, has been to identify ways by which complex multi-level material structures can be effectively modeled. One way to achieve this is to use coarse-graining approaches, where physical relationships can be effectively described with reduced dimensionality. In this paper we report an integrated deep neural network architecture that first learns coarse-grained representations of complex hierarchical microstructure data via a discrete variational autoencoder and then utilizes an attention-based diffusion model solve both forward and inverse problems, including a capacity to solve degenerate design problems. As an application, we demonstrate the method in the analysis and design of hierarchical highly porous metamaterials within the context of nonlinear stress–strain responses to compressive deformation. We validate the mechanical behavior and mechanisms of deformation using embedded-atom molecular dynamics simulations carried out for copper and nickel, showing good agreement with the design objectives.
Quantum multicritical behavior for coupled optical cavities with driven laser fields
Authors: Hu Yutao , Zhou Yu , Luo Wenchen , Trombettoni Andrea , Huang Guoxiang 
Published: April 2023

AbstractQuantum phase transitions with multicritical points are fascinating phenomena occurring in interacting quantum many-body systems. However, multicritical points predicted by theory have been rarely verified experimentally; finding multicritical points with specific behaviors and realizing their control remains a challenging topic. Here, we propose a system that a quantized light field interacts with a two-level atomic ensemble coupled by microwave fields in optical cavities, which is described by a generalized Dicke model. Multicritical points for the superradiant quantum phase transition are shown to occur. We determine the number and position of these critical points and demonstrate that they can be effectively manipulated through the tuning of system parameters. Particularly, we find that the quantum critical points can evolve into a Lifshitz point (LP) if the Rabi frequency of the light field is modulated periodically in time. Remarkably, the texture of atomic pseudo-spins can be used to characterize the quantum critical behaviors of the system. The magnetic orders of the three phases around the LP, represented by the atomic pseudo-spins, are similar to those of an axial next-nearest-neighboring Ising model. The results reported here are beneficial for unveiling intriguing physics of quantum phase transitions and pave the way towards to find novel quantum multicritical phenomena based on the generalized Dicke model.
Improvement in structural, thermal, charge transport and mechanical properties of poly (methyl methacrylate)/polyindole composites for optoelectronic devices
Authors: Sebastian Annumaria , Gopika R , Anju R , Verma Meenakshi , Ramesan M T 
Published: April 2023

Abstract
This study encompasses the synthesis, characterization, optical properties, thermal, mechanical, and electrical characteristics of a series of in situ polymerized poly (methyl methacrylate) (PMMA) with different contents of polyindole (PIN) composites. The formation of composites was characterized by FTIR, UV-visible, XRD, FE-SEM, AFM, DSC and TGA. Tensile testing techniques was used to determine mechanical properties such as tensile strength, modulus, hardness and impact strength of PMMA/PIN. Impedance spectroscopy was used to study the electrical properties of the prepared composites. The interaction between the NH moiety of indole and ester groups of PMMA was established through FTIR. The optical bandgap energy determined from UV spectroscopy shows a declining trend, whereas the refractive index grows significantly with the loading of indole up to 5 wt%. The decrease in broadness and intensity of the XRD peak confirmed the presence of an indole component in the PMMA matrix. The holes in the surface morphology of PMMA was changed into uniformly dispersed particles, confirming the dispersion of PIN in the PMMA matrix. The surface roughness obtained from AFM increases with the addition of PIN to PMMA. DSC measurements show that the glass transition temperature of the polymer increases with the inclusion of the indole moiety. TGA indicates that the addition of PIN has a positive effect on the thermal stability of PMMA/PIN composites. The results of mechanical testing showed an increase in Youngs modulus, tensile strength, and impact strength with the addition of PIN. The AC impedance results show an increase in the dielectric constant and conductivity of PMMA with the PIN addition. PMMA/PIN composites with high tensile strength, conductivity and dielectric constant can be used in the fabrication of optoelectronic devices and EMI shielding.
Iridium and gold alloy beta gallium oxide expected to achieve p-type conductivity
Authors: Wei Dong , Ma Yaqiang , Guo Gaofu , Li Yi , Yu Heng , Tang Yanan , Dai Xianqi 
Published: April 2023

Abstract
The beta monoclinic gallium oxide (β-Ga2O3) is a wide-bandgap material with promising applications in high-power electronics, but bottleneck problem of p-type conductivity has become the biggest obstacle to device performance improvement. The effective p-type doping can be achieved in β-(Ir
x
Au
y
Ga1-x-y
)2O3 alloys, promising to be synthesised in the laboratory, from an energy perspective. The β-(Ir
x
Ga1-x
)2O3 exhibits an extended valence band with a maximum of 1.94 eV at the edge of the valence band. The location and bandwidth of the extended valence band can be changed with the Ir concentration. The Au substitution at the Ga(2) site actually creates a relatively shallow level, contrary to the expected deep acceptors. The 2p orbital of the O atom easily coupling with the doped atomic orbital to appear as a hole-polaronic state, while the higher energy of the Au-doped hole state avoids coupling with the valence band maximum of the host material. Theoretical feasibility of p-type doping of β-(Ir
x
Au
y
Ga1-x-y
)2O3 is achieved.
Analysis of a gas sensor based on one-dimensional photonic crystal structure with a designed defect cavity
Authors: Kumar Narendra , Suthar Bhuvneshwer , Nayak Chittranjan , Bhargava Anami 
Published: April 2023

Abstract
A symmetric one-dimensional photonic crystal configuration with defect layer is proposed for an optical gas sensor based device application. Here, Silicon and Si3N4 are considered as materials of dielectric layers with zero value of extinction coefficient in the wavelength range of concern. The transmission of PC configuration is estimated using the transfer matrix approach in case of configuration with and without defect, and the infiltrated gas is treated as defect layer. On the basis of the defect mode’s wavelength, gas can be determined. In addition, quality factor and sensitivity of the device are improved due to the variation of refractive index of layer B, thickness of defect, angle of incidence and the number of unit cells on either side of defect layer. By making analysis of the effect of these parameters on the sensitivity and quality factor, interesting results have been obtained and conclusions drawn. We have also proposed and investigated a symmetric structure with defect made with a single material to improve optical sensing parameters. Further for the sake of comparison, the various gases are used to show improved sensing characteristics for respective gases, which can be used to determine gas. It is inferred that such refractive index optical sensor based on defect mode position is highly sensitive and offers precise optical sensing characteristics and possibly find applications in gas detection.
Reflection characteristics of water treeing insulation in medium voltage cables
Authors: Ye Yuan , Hu Xiao 
Published: April 2023

Abstract
This paper presents an analytical model based on wave reflection of dual interfaces for studying the reflection due to water treeing in the cross-linked polyethylene (XLPE) insulation of medium voltage cables. The model is expected to predict the reflection characteristics more accurately than that only considering reflection of a single interface. Experiments on a cable sample with mimic water trees are conducted to confirm the effectiveness of the presented model. The model can potentially be used to relate time-domain reflectometry (TDR) measurement results with characteristics of water treeing insulation in the cables.
Influence of the quantum well dielectric permittivity on the two-dimensional plasmon-phonon
Authors: Aleshkin V Ya , Dubinov A A , Rudakov A O 
Published: April 2023

Abstract
The work is devoted to a theoretical study of the effect of polarizability associated with quantum well lattice vibrations and filled electron bands on the properties of two-dimensional plasmon-phonons in InAs/AlSb and CdHgTe/CdTe single quantum well (QW) heterostructures. The spectra for the considered excitations are obtained without taking into account the spatial dispersion and with it taken into account in the framework of random phase approximation (RPA). The frequency dependence of the plasmon-phonon absorption coefficient is calculated. It is shown that taking into account the contribution of QW phonons and electrons of filled bands to the polarizability leads to the conclusion that there is a maximum frequency of plasmon-phonons and to the conclusion that the existence of plasmon-phonon modes requires that the electron mobility exceed a certain minimum value.
Ambient relative humidity effects on mechanical properties of FDM 3D printed PLA components
Authors: Demirtaş Mehmet Selim , Avcıoğlu Emir 
Published: April 2023

AbstractIn this study, poly(lactic acid) samples were printed by using the fused deposition method whereas ambient relative humidity conditions and filling percentages varied. The effects of the relative humidity on the mechanical and thermal properties of the samples were investigated. It was observed that the mechanical properties of the samples decreased as the relative humidity increased and that specimens with low filling percentages were affected more by relative humidity. Differential scanning calorimetry results showed that the glass transition temperature, melting point, and crystallization temperature were inversely correlated with relative humidity. The surface structure was also negatively affected by the relative humidity, and the intensity and size of the voids increased as the relative humidity increased. In addition, this study recommends that the manufacture of materials with a 3D printer be conducted at low humidity to achieve high flexural strength and modulus.
Wavelength-tunable mode-locked laser using zinc phosphate as a saturable absorber at 1.9 μm
Authors: Ahmad H , Nizamani B , Samion M Z , Azam A D , Yusoff N 
Published: April 2023

Abstract
Metal phosphates have emerged as low-cost inorganic materials suitable for high-performance energy storage and conversion devices. The photoluminescence properties of metal phosphates are now being explored for their optoelectronic applications. Among them, zinc phosphate is the composition of metal zinc and phosphoric acid. In this work, we have demonstrated the synthesis of zinc phosphate by the solvothermal method and its potential as a saturable absorber (SA) to generate a tunable mode-locked laser at 1.9 μm. Zinc phosphate was coated over arc-shaped fiber and incorporated in a thulium-holmium doped fiber laser (THDFL) to achieve the mode-locking. Soliton mode-locked pulses were achieved at a center wavelength of 1893 nm with the pulse duration, repetition rate, and signal-to-noise ratio (SNR) of 1.12 ps, 12 MHz, and 68 dB, respectively. The center wavelength of the mode-locked laser was tunable from 1893 to 1898.4 nm, and the pulse duration ranged between 1.12 to 1.4 ps. To the authors’ knowledge, this is the first demonstration of a wavelength-tunable mode-locked laser using zinc phosphate as a SA at 1.9 μm.
Some disquisitions on cosmological 2-form dualities
Authors: Aoki Katsuki , Beltrán Jiménez Jose , Figueruelo David 
Published: April 2023

Abstract
In this work we study different aspect of self-interacting 2-form fields with special emphasis in their cosmological applications. We provide the explicit construction of how massless 2-forms are compatible with the cosmological principle without resorting to the dual scalar field formulation. In terms of the 2-form, the residual Euclidean group is non-trivially realised by means of a combination of external spatial translations and internal gauge transformations. After presenting the general discussion of the dualities in cosmological scenarios, we analyse particular examples for some singular models and discuss in some detail the dual descriptions of the DBI, the cuscuton and the ghost condensate as well as the role of the duality in the effective field theories of cosmological perturbations. We then proceed to analysing scenarios with several self-interacting massless 2-forms and we show that they naturally provide the dual description of a solid. We then show how the perfect fluid and superfluids can be obtained by taking the appropriate limits in the dual formulations. We finally consider the case of massive 2-forms and their duals and briefly discuss their potential signatures in gravitational waves astronomy.
How Dark the Sky: The JWST Backgrounds
Authors: Rigby Jane R. , Lightsey Paul A. , García Marín Macarena , Bowers Charles W. , Smith Erin C. , Glasse Alistair , McElwain Michael W. , Rieke George H. , Chary Ranga-Ram , Liu Xiang (Cate) , Clampin Mark , Kimble Randy A. , Kinzel Wayne , Laidler Vicki , Mehalick Kimberly I. , Noriega-Crespo Alberto , Shivaei Irene , Skelton Dennis , Stark Christopher , Temim Tea , Wei Zongying , Willott Chris J. 
Published: April 2023

Abstract
We describe the sources of stray light and thermal background that affect JWST observations, report actual backgrounds as measured from commissioning and early-science observations, compare these background levels to prelaunch predictions, estimate the impact of the backgrounds on science performance, and explore how the backgrounds probe the achieved configuration of the deployed observatory. We find that for almost all applications, the observatory is limited by the irreducible astrophysical backgrounds, rather than scattered stray light and thermal self-emission, for all wavelengths λ < 12.5 μm, thus meeting the level 1 requirement. This result was not assured given the open architecture and thermal challenges of JWST, and it is the result of meticulous attention to stray light and thermal issues in the design, construction, integration, and test phases. From background considerations alone, JWST will require less integration time in the near-infrared compared to a system that just met the stray-light requirements; as such, JWST will be even more powerful than expected for deep imaging at 1–5 μm. In the mid-infrared, the measured thermal backgrounds closely match prelaunch predictions. The background near 10 μm is slightly higher than predicted before launch, but the impact on observations is mitigated by the excellent throughput of MIRI, such that instrument sensitivity will be as good as expected prelaunch. These measured background levels are fully compatible with JWST’s science goals and the Cycle 1 science program currently underway.
Applied Machine-Learning Models to Identify Spectral Sub-Types of M Dwarfs from Photometric Surveys
Authors: Sithajan Sirinrat , Meethong Sukanya 
Published: April 2023

Abstract
M dwarfs are the most abundant stars in the Solar Neighborhood and they are prime targets for searching for rocky planets in habitable zones. Consequently, a detailed characterization of these stars is in demand. The spectral sub-type is one of the parameters that is used for the characterization and it is traditionally derived from the observed spectra. However, obtaining the spectra of M dwarfs is expensive in terms of observation time and resources due to their intrinsic faintness. We study the performance of four machine-learning (ML) models—K-Nearest Neighbor (KNN), Random Forest (RF), Probabilistic Random Forest (PRF), and Multilayer Perceptron (MLP)—in identifying the spectral sub-types of M dwarfs at a grand scale by deploying broadband photometry in the optical and near-infrared. We trained the ML models by using the spectroscopically identified M dwarfs from the Sloan Digital Sky Survey (SDSS) Data Release (DR) 7, together with their photometric colors that were derived from the SDSS, Two-Micron All-Sky Survey, and Wide-field Infrared Survey Explorer. We found that the RF, PRF, and MLP give a comparable prediction accuracy, 74%, while the KNN provides slightly lower accuracy, 71%. We also found that these models can predict the spectral sub-type of M dwarfs with ∼99% accuracy within ±1 sub-type. The five most useful features for the prediction are r − z, r − i, r − J, r − H , and g − z, and hence lacking data in all SDSS bands substantially reduces the prediction accuracy. However, we can achieve an accuracy of over 70% when the r and i magnitudes are available. Since the stars in this study are nearby (d ≲ 1300 pc for 95% of the stars), the dust extinction can reduce the prediction accuracy by only 3%. Finally, we used our optimized RF models to predict the spectral sub-types of M dwarfs from the Catalog of Cool Dwarf Targets for the Transiting Exoplanet Survey Satellite, and we provide the optimized RF models for public use.
Thermalization with a multibath: an investigation in simple models
Authors: Battista Carollo Giovanni , Corberi Federico , Gonnella Giuseppe 
Published: April 2023

Abstract
We study analytically and numerically a couple of paradigmatic spin models, each described in terms of two sets of variables attached to two different thermal baths with characteristic timescales T and τ and inverse temperatures B and β. In the limit in which one bath becomes extremely slow (

τ
→
∞

), such models amount to a paramagnet and to a one-dimensional ferromagnet in contact with a single bath. Our study is also motivated by analogies with disordered systems where widely separated timescales associated with different effective temperatures emerge. We show that these systems reach a stationary state in a finite time for any choice of B and β. We determine the non-equilibrium fluctuation-dissipation relation between the autocorrelation and the response function in such a state and, from that, we discuss if and how thermalization with the two baths occurs and the emergence of a non-trivial fluctuation-dissipation ratio.
Influence of ITO Target on Structural, Optical, and Electrical Properties of Thin Films Deposited by Magnetron Sputtering
Authors: Yang Shumin , Zhang Wei , Xie Bin , Xiong Mingyao 
Published: April 2023

Abstract
Indium tin oxide (ITO) targets possess good performances, thereby used to produce high-quality ITO films in transparent electrodes of various optoelectronic devices. The performance of the target greatly affects the performances of prepared ITO films. However, effect of the overall performance of ITO targets on ITO films performance is still not fully understood. ITO films were prepared with four targets by magnetron sputtering in the similar condition in this study. Effects of crystal structure, resistivity, and oxygen content of the targets on photoelectric performances of ITO films were all evaluated. Results showed the important effect of target properties on obtained film characteristics. ITO films prepared by low resistivity targets are more evenly distributed on the substrate surface. Meanwhile, oxygen content of obtained ITO films decreased as oxygen content of ITO targets used in sputtering process increased. This also significantly improved the photoelectric performances. ITO thin films deposited using targets with low resistivity and low oxygen content exhibited excellent photoelectric performances. In this experiment, the prepared ITO film illustrated the lowest resistivity of 1.75×10−4 Ω·cm and average transmittance of 90.5%. In sum, these findings provided a certain experimental basis for further improving the performances of ITO films.
Research on Preparation and Performance of Aerogel Rock Wool Thermal Insulation Composite Materials
Authors: Lu Guozhong , He Guangming , Ma Guoru , Li Yuyang , Li Jingyi 
Published: April 2023

Abstract
Reasearch and experimental tests had been operated on the preparation process and performance of aerogel rock wool composite thermal insulation material respectively, including the effects of solid contents, thickness and density of the board on thermal conductivity of the aerogel rock wool composite material, and the morphology and energy spectrum of the material were analyzed. The results showed that aerogel was beneficial to reduce the thermal conductivity of aerogel rock wool composite, and the thermal insulation performance of ordinary rock wool was greatly improved.
Operator-Compensation Schemes Combining with Implicit Integration Factor Method for the Nonlinear Dirac Equation
Authors: Zhang Ducui , Li Xianggui , Hua Dongying , Li Yanjing 
Published: April 2023

Abstract
A high-order accuracy numerical method for the (1+1)-dimensional nonlinear Dirac (NLD) equation is given in this work. For the spatial discretization, high-order operator-compensation technology is adopted, then semi-discrete scheme is obtained. Energy conservation and charge conservation are shown for the semi- discrete scheme. For the temporal discretization, implicit integration factor ( IIF) method is utilized to deal with the ordinary differential equations that are obtained from the semi-discrete scheme. The accuracy of the high-order numerical method is verified by numerical experiments, and the interaction dynamics of NLD solitary waves are investigated.