bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting the factors influencing construction enterprises’ adoption of green development behaviors using artificial neural network
Authors: Li Xingwei , He Jinrong , Huang Yicheng , Li Jingru , Liu Xiang , Dai Jiachi
Published: July 2022

The construction industry occupies a high proportion of the global economy. However, with the energy consumption of construction enterprises, it still brings a series of serious environmental problems. Construction enterprises should take active green development behavior to respond. Based on enterprises’ green development behavior, this paper explores the influencing factors of green development behavior adopted by construction enterprises in China. Through literature analysis, this paper identifies that construction enterprises’ adoption of green development behaviors is influenced by technological, organizational and environmental factors. Then this paper constructs an index system of the influencing factors of green development behaviors adopted by enterprises. According to the data of construction enterprises from 2000 to 2020 of National Bureau of Statistics, an artificial neural network is used to construct the prediction model of influencing factors of green development behavior adopted by construction enterprises. The conclusions are as follows. (1) Construction enterprises’ adoption of green development behavior shows an upward trend over time. (2) Market share of construction enterprises is the most important factor to promote construction enterprises’ adoption of green development behavior. (3) The prediction model of influencing factors constructed in this paper is verified to be effective by the technology-organization-environment framework. This paper provides a reference for construction enterprises and the government to promote enterprises to adopt green development behavior, which is beneficial for construction enterprises to achieve green development faster.
Quasitriangular Hopf group-quasialgebras and generalized quantum Yang–Baxter equations
Authors: Zhang Senlin , Wang Shuanhong
Published: July 2022

We introduce and study a large class of algebras (possibly nonassociative) with group-coalgebraic structures, Hopf nonassociative group-coalgebras, which provide a unifying framework for classical Hopf algebras, Turaev’s Hopf group-coalgebras, and Hopf quasigroups. Then, we introduce and discuss the notion of a quasitriangular Hopf π-quasialgebra and show that the category Qrep(H)R of quasirepresentations over any quasitriangular Hopf π-quasialgebra (H, R) is a braided π-category. As an application of our theory, we give a new solution to the generalized quantum Yang–Baxter equation.
Broadband (kHz–GHz) characterization of instabilities in Hall thruster inside a metallic vacuum chamber
Authors: Mazières V. , Gaboriau F. , Guglielmi A. , Laquerbe V. , Pascaud R. , Pascal O.
Published: July 2022

Hall thrusters are known to exhibit a large variety of instabilities. Their physical mechanisms have been identified at low (kHz) and intermediate (MHz) frequencies, even though they are still not fully understood. Furthermore, electromagnetic radiations generated by Hall thrusters, named “self-emission” of the thruster, have been measured from kHz to MHz as expected from the identified instabilities, but also at higher frequencies. The origin of the high frequency (GHz) self-emission remains for now unknown. Assessing this self-emission, that is important for understanding the physics of Hall thrusters as well as for electromagnetic compatibility issues with the spacecraft, is challenging. Another aspect that makes the understanding of the physics of Hall thrusters complex comes from the eventual coupling between instabilities, which has been recently suggested and observed. The aim of this paper is to explore the possibility of characterizing simultaneously instabilities in Hall thrusters on a broadband frequency range (from kHz to GHz) in situ, meaning in a conventionally used vacuum chamber where Hall thrusters are usually operated. We show in this paper that, despite the reverberant nature of the vacuum metallic chamber, useful information is extracted at low and intermediate frequencies and even at high frequency from the measurements done with an antenna in this environment.
Microfluidic techniques for isolation, formation, and characterization of circulating tumor cells and clusters
Authors: Macaraniag Celine , Luan Qiyue , Zhou Jian , Papautsky Ian
Published: July 2022

Circulating tumor cell (CTC) clusters that are shed from the primary tumor into the bloodstream are associated with a poor prognosis, elevated metastatic potential, higher proliferation rate, and distinct molecular features compared to single CTCs. Studying CTC clusters may give us information on the differences in the genetic profiles, somatic mutations, and epigenetic changes in circulating cells compared to the primary tumor and metastatic sites. Microfluidic systems offer the means of studying CTC clusters through the ability to efficiently isolate these rare cells from the whole blood of patients in a liquid biopsy. Microfluidics can also be used to develop in vitro models of CTC clusters and make possible their characterization and analysis. Ultimately, microfluidic systems can offer the means to gather insight on the complexities of the metastatic process, the biology of cancer, and the potential for developing novel or personalized therapies. In this review, we aim to discuss the advantages and challenges of the existing microfluidic systems for working with CTC clusters. We hope that an improved understanding of the role microfluidics can play in isolation, formation, and characterization of CTC clusters, which can lead to increased sophistication of microfluidic platforms in cancer research.
Surface segregation and relaxation in free-standing Ni1–x
Cux alloy nanofilms
Authors: Ji Xiang , Sun Sheng , Zhang Tong-Yi
Published: July 2022

The interaction between mechanics and chemistry plays an essential and critical role in the surface segregation and relaxation in nanoscale alloys. Following the thermodynamics analysis based on surface eigenstress, the present study takes the free-standing nanometer thick films of Ni1–xCux solid solutions with face-centered cubic (fcc) crystalline structures as an example to investigate surface segregation of Cu and relaxation of the films. Hybrid Monte Carlo and Molecular Dynamics (MCMD) simulations are conducted on free-standing Ni1–xCux alloys of (100) and (111) nanofilms. The MCMD simulations verify the theoretical analytic results and determine the values of parameters involved in the theoretical analysis. Especially, the parameter of the differentiation in reference chemical potential behaves like the molar free energy of segregation in the McLean adsorption isotherm, and the differentiation in chemical composition induced eigenstrain plays also an important role in surface segregation and relaxation. The integrated theoretical and numerical study exhibits that both surface excess Cu concentration and apparent biaxial Young's modulus of Ni1–xCux nanofilms depend on the nominal Cu concentration and the film thickness.
Deviatoric stress driven transient melting below the glass transition temperature in shocked polymers
Authors: Macatangay Jalen , Hamilton Brenden W. , Strachan Alejandro
Published: July 2022

The relaxation of polymers around and below their glass transition temperature is governed by a range of correlated unit processes with a wide range of timescales. The fast deformation rates of shock loading can suppress a significant fraction of these processes resulting in dynamical glass transition in rubbers. In this article, we report the inverse, a transient melting of a glassy polymer under shock loading. The large deviatoric stresses near the shock front induce fast transitions in backbone dihedral angles and a stress relaxation characteristic of polymer melts. This is followed by slower relaxation expected for glasses.
On the nature of the chemical bond in valence bond theory
Authors: Shaik Sason , Danovich David , Hiberty Philippe C.
Published: July 2022

This Perspective outlines a panoramic description of the nature of the chemical bond according to valence bond theory. It describes single bonds and demonstrates the existence of a “forgotten family” of charge-shift bonds (CSBs) in which the entire/most of the bond energy arises from the resonance between the covalent and ionic structures of the bond. Many of the CSBs are homonuclear bonds. Hypervalent molecules (e.g., XeF2) are CSBs. This Perspective proceeds to describe multiple bonded molecules with an emphasis on C2 and 3O2. C2 has four electron pairs in its valence shell and, hence, 14 covalent structures and 1750 ionic structures. This Perspective outlines an effective methodology of peeling the electronic structure to the minimal and important number of structures: a dominant structure that displays a quadruple bond and two minor structures with π + σ bonds, which stabilize the quadruple bond by resonance. 3O2 is chosen because it is a diradical, which is persistent and life-sustaining. It is shown that the persistence of this diradical is due to the charge-shift bonding of the π-3-electron bonds. This section ends with a discussion of the roles of π vs σ in the geometric preferences of benzene, acetylene, ethene, and their Si-based analogs. Subsequently, this Perspective discusses bonding in clusters of univalent metal atoms, which possess only parallel spins (n+1Mn), and are nevertheless bonded due to the resonance interactions that stabilize the repulsive elementary structure (all spins are up). The bond energy reaches ∼40 kcal/mol for a pair of atoms (in n+1Cun; n ∼ 10–12). The final subsection discusses singlet excited states in ethene, ozone, and SO2. It demonstrates the capability of the breathing-orbital VB method to yield an accurate description of a variety of excited states using merely 10 or few VB structures. Furthermore, the method underscores covalent structures that play a key role in the correct description and bonding of these excited states.
Design and evaluation of a dual-beam read/write configuration for optical storage
Authors: Liu Mingyuan , Ma Jianshe , Su Ping , Yang Xianwen , Hou Bowen
Published: July 2022

Increasing the number of read/write layers and ensuring the quality of read/write signals are the key factors to enhance the optical storage capacity. However, limited by the single optical path, the structure, and the material of the disk, the existing system reads and writes up to 16 layers. In the existing optical storage system design, the optical path design and the signal model are independent of each other, so the signal quality based on the signal model can only be evaluated after the implementation of the optical path. We propose a dual-beam read/write optical path for the optical storage system, which breaks through the limitation of the single optical path and can read/write multilayers. The servo detection signals and servo margins show that the dual-beam read/write system has good error detection capability and strong robustness. The servo error signal is calculated according to the relationship between the wavefront aberration, relative coordinate system displacement difference, and servo error of the optical system, thus deriving a quantifiable signal evaluation model. The effectiveness of the model is verified by experiments. The signal evaluation model breaks through the limitations of the traditional optical design method for the optical storage system and can guide the optical design from the signal perspective. The dual-beam optical path for multilayer optical storage systems provides a broader range of ideas for enhancing optical storage capacity.
Numerical analysis of two spheres falling side by side
Authors: Chiu Chia-Lin , Fan Chia-Ming , Chu Chia-Ren
Published: July 2022

This study numerically investigates the interaction between two side-by-side free-falling spheres in water. The predicted S-curve falling trajectories of the spheres were verified by laboratory experiments, and the attraction–repulsion of lateral force on the vertically falling spheres is investigated to give a better understanding of the evolution of the lateral force by excluding the effect of the transverse motion. The flow pattern around the spheres reveals that the wake flows play an essential role in the fluid–sphere interaction. Then, the two free-falling spheres with transverse motion are considered to examine the interacting force and the crosswise strength of wake flows. This study attempts to explore the wake flow as the possible mechanism for the S-curve falling trajectories of two spheres. Finally, the falling processes of the two spheres are simulated in a deeper tank to inspect the falling trajectories and the reappearing flow characteristics.
Research on coupled cavity mechanical tuning extended interaction oscillator with broad tuning range
Authors: Qing Jie , Niu Xinjian , Liu Yinghui , Guo Guo , Li Hongfu
Published: July 2022

This paper proposes a new way to improve the tuning range of the extended interaction oscillator (EIO). Compared with the conventional EIO structure, the fundamental wave changes from the forward wave to the backward wave when the circuit structure changes from the strong-coupling characteristic of the grating to the weak-coupling characteristic. Simultaneously, the tuning range of the EIO can be greatly enhanced by mechanically tuning the coupling cavity. The results show that, compared with the strong-coupling structure of the grating, the extended interaction oscillation circuit has stronger dispersion sensitivity and greater frequency tuning characteristics under the weak-coupling characteristics of the grating. By mechanically tuning the width of the coupling cavity by 0.8 mm, its center frequency can be varied by 9.5 GHz. This paper also studies and compares the electronic displacement jump phenomenon that occurs in the mechanical tuning process. Similar to the electronic voltage tuning, the output dips suddenly at the operating point of the coupling mismatch. The effective output can be obtained by changing the operating mode in conjunction with electronic tuning. This article provides a new reference method for expanding the tuning range of the extended interaction oscillator.
Point defect creation by proton and carbon irradiation of α-Ga2O3
Authors: Polyakov Alexander Y. , Nikolaev Vladimir I. , Meshkov Igor N. , Siemek Krzysztof , Lagov Petr B. , Yakimov Eugene B. , Pechnikov Alexei I. , Orlov Oleg S. , Sidorin Alexey A. , Stepanov Sergey I. , Shchemerov Ivan V. , Vasilev Anton A. , Chernykh Alexey V. , Losev Anton A. , Miliachenko Alexandr D. , Khrisanov Igor A. , Pavlov Yu.S. , Kobets U. A. , Pearton Stephen J.
Published: July 2022

Films of α-Ga2O3 grown by Halide Vapor Phase Epitaxy (HVPE) were irradiated with protons at energies of 330, 400, and 460 keV with fluences 6 × 1015 cm−2 and with 7 MeV C4+ ions with a fluence of 1.3 × 1013 cm−2 and characterized by a suite of measurements, including Photoinduced Transient Current Spectroscopy (PICTS), Thermally Stimulated Current (TSC), Microcathodoluminescence (MCL), Capacitance–frequency (C–f), photocapacitance and Admittance Spectroscopy (AS), as well as by Positron Annihilation Spectroscopy (PAS). Proton irradiation creates a conducting layer near the peak of the ion distribution and vacancy defects distribution and introduces deep traps at Ec-0.25, 0.8, and 1.4 eV associated with Ga interstitials, gallium–oxygen divacancies VGa–VO, and oxygen vacancies VO. Similar defects were observed in C implanted samples. The PAS results can also be interpreted by assuming that the observed changes are due to the introduction of VGa and VGa–VO.
The dynamics of an externally driven nanoscale beam that is under high tension and immersed in a viscous fluid
Authors: Barbish J. , Ti C. , Ekinci K. L. , Paul M. R.
Published: July 2022

We explore the dynamics of a nanoscale doubly clamped beam that is under high tension, immersed in a viscous fluid, and driven externally by a spatially varying drive force. We develop a theoretical description that is valid for all possible values of tension, includes the motion of the higher modes of the beam, and accounts for a harmonic force that is applied over a limited spatial region of the beam near its ends. We compare our theoretical predictions with experimental measurements for a nanoscale beam that is driven electrothermally and immersed in air and water. The theoretical predictions show good agreement with experiments, and the validity of a simplified string approximation is demonstrated.
Semi-experimental equilibrium (r
eSE) and theoretical structures of hydrazoic acid (HN3)
Authors: Owen Andrew N. , Sahoo Nitai P. , Esselman Brian J. , Stanton John F. , Woods R. Claude , McMahon Robert J.
Published: July 2022

Hydrazoic acid (HN3) is used as a case study for investigating the accuracy and precision by which a molecular structure—specifically, a semi-experimental equilibrium structure (reSE)—may be determined using current state-of-the-art methodology. The influence of the theoretical corrections for effects of vibration–rotation coupling and electron-mass distribution that are employed in the analysis is explored in detail. The small size of HN3 allowed us to deploy considerable computational resources to probe the basis-set dependence of these corrections using a series of coupled-cluster single, double, perturbative triple [CCSD(T)] calculations with cc-pCVXZ (X = D, T, Q, 5) basis sets. We extrapolated the resulting corrections to the complete basis set (CBS) limit to obtain CCSD(T)/CBS corrections, which were used in a subsequent reSE structure determination. The reSE parameters obtained using the CCSD(T)/cc-pCV5Z corrections are nearly identical to those obtained using the CCSD(T)/CBS corrections, with uncertainties in the bond distances and angles of less than 0.0006 Å and 0.08°, respectively. The previously obtained reSE structure using CCSD(T)/ANO2 agrees with that using CCSD(T)/cc-pCV5Z to within 0.000 08 Å and 0.016° for bond distances and angles, respectively, and with only 25% larger uncertainties, validating the idea that reSE structure determinations can be carried out with significantly smaller basis sets than those needed for similarly accurate, strictly ab initio determinations. Although the purely computational re structural parameters [CCSD(T)/cc-pCV6Z] fall outside of the statistical uncertainties (2σ) of the corresponding reSE structural parameters, the discrepancy is rectified by applying corrections to address the theoretical limitations of the CCSD(T)/cc-pCV6Z geometry with respect to basis set, electron correlation, relativity, and the Born–Oppenheimer approximation, thereby supporting the contention that the semi-experimental approach is both an accurate and vastly more efficient method for structure determinations than is brute-force computation.
Evaluation of Aboriginal and Torres Strait Islander smoking cessation interventions with pregnant women in Australia: utilising a culturally appropriate tool
Authors: Tane Moana , Stevenson Leah C. , Cameron Liz , Gould Gillian S.
Published: July 2022

The purpose of this article was to review and evaluate three Australian projects with a focus on smoking cessation and Aboriginal and Torres Strait Islander pregnant women, funded under the Tackling Indigenous Smoking Innovation Grants Scheme, Australian Department of Health. The aim was to determine the impacts of culturally appropriate smoking cessation support for pregnant Aboriginal and Torres Strait Islander women. To provide an equity-focused lens to the review, our team of Indigenous and non-Indigenous researchers utilised an Australian-developed assessment tool: the ‘Cultural Identity Interventions Systematic Review Proforma’. The tool was used to measure cultural approaches across a range of domains, and these were independently assessed by two reviewers, along with an assessment of the projects’ smoking cessation outcomes. The results were compared to the evidence base in relation to aims, methods, results and conclusions, and consensus for scoring was reached. The review found that these Tackling Indigenous Smoking projects about pregnancy intentionally and effectively incorporated culturally based approaches that sought to work with the participants in culturally informed ways. Each project utilised existing social networks and partnerships to provide their participants with access to a range of community resources, adding value to existing programs.
The emergence of conjunctions and phrasal coordination in Khanty
Authors: Borise Lena , Kiss Katalin É.
Published: July 2022

Prior to widespread contact with Russian, Khanty (Uralic; Finno-Ugric) did not have overt conjunctions or phrasal
coordination. Instead, Khanty texts from the late 19th–early 20th centuries only include examples of conjunction-less clausal juxtaposition,
which was used for both clausal and phrasal coordination. By comparing Khanty texts over the 20th century, we trace the emergence of overt
conjunctions and coordination of phrasal constituents. We show that overt conjunctions first appeared in the context of clausal
coordination, followed by coordination of smaller phrases. Based on novel elicitation data, we demonstrate that, in contemporary Khanty, (i)
overt conjunctions are commonplace, (ii) coordinated clausal constituents may be derived via phrasal coordination or clausal coordination
with conjunction reduction/ellipsis, but (iii) ellipsis of syntactic heads is banned (nouns & postpositions) or dispreferred (verbs).
Based on this diachronic picture, we conclude that the coordination of phrasal constituents only emerged in Khanty once overt conjunctions
became available. We derive this correlation from the Maximize On-line Processing principle (Hawkins
2004), and show that this maxim, usually invoked in the context of speech planning and production, can be successfully applied to
modelling language change.
Prognostics and health management for piezoresistive pressure sensor based on improved gated recurrent unit networks
Authors: Ruan Yi , Yuan Lifen , He Yigang , Li Zhigang , Yuan Weibo , Lu Li
Published: July 2022

Application fields for piezoresistive pressure sensors have become increasingly extensive in recent years. So a high reliability of the sensor is also required. However, considering that some sensors operate in hostile environments,the need to ensure continuous operation accuracy, prognostics, and health management (PHM) for piezoresistive pressure sensors should not be ignored. To solve this problem, a fault diagnosis and prognostic method that combines a support vector machine (SVM) and deep gated recurrent unit (DGRU) network optimized by hunter–prey optimization (HPO) is proposed in this paper. First, three sensor fault types are defined. Second, SVM is adopted to realize the fault diagnosis. Third, two layers of DGRU are employed to predict the health index, which is defined to represent the health state of the sensor. Meanwhile, the optimal parameters of the DGRU are optimized by HPO algorithms. Finally, the remaining useful life can be estimated by the predicted health index and failure threshold. The method proposed in this paper is proved to be effective and accurate. The fault diagnosis accuracy is 100% in the three fault types defined by this paper. The minimum mean absolute error is 6 × 10−5. It proves the proposed method of PHM in this paper is viable in a real application.
Molecular dynamics study of phonon thermal transport in borophene with random vacancy defects
Authors: Xu Dajie , Zhou Man , Wu Bingyang , Liu Jiaju , Zhang Ping
Published: July 2022

This study uses non-equilibrium molecular dynamics simulation to investigate the effect of random vacancy defects on the in-plane thermal conductivity of borophene phonon dispersion curves and phonon group velocities are used to explain the anisotropy of the thermal conductivity of borophene nanosheets and the transmission characteristics of the acoustic and optical branches. Further calculations for the in-plane thermal conductivity of borophene with random vacancy defects are carried out, and the calculations show that the thermal conductivity gradually decreases to a steady state with increasing defect concentration. The phonon density of states and phonon participation rate are used to explain describe the activity of phonons in borophene for further explaining the change of thermal conductivity. Finally, the effect of defects on thermal conductivity is further verified by the spatial distribution of localized intensity of borophene nanosheets.
Dynamics of a predator–prey system with nonlinear prey-taxis
Authors: Liu Changfeng , Guo Shangjiang
Published: July 2022

In this paper, we investigate a predator–prey system with nonlinear prey-taxis under Neumann boundary condition. For a class of chemotactic sensitive functions, we obtain the existence and boundedness of global classical solutions for initial boundary value problems in arbitrary dimensional space. In addition, we also study the local stability of the constant steady state solution, and obtain the global asymptotic stability of the steady state solution under different predation intensity by constructing appropriate Lyapunov functions. Furthermore, the steady state bifurcation, Hopf bifurcation and fold-Hopf Singularity are analysed in detail by using Lyapunov–Schmidt reduction method.
Characteristic approach to the soliton resolution
Authors: Bizoń Piotr , Cownden Bradley , Maliborski Maciej
Published: July 2022

As a toy model for understanding the soliton resolution phenomenon we consider a characteristic initial boundary value problem for the 4d equivariant Yang–Mills equation outside a ball. Our main objective is to illustrate the advantages of employing outgoing null (or asymptotically null) foliations in analyzing the relaxation processes due to the dispersal of energy by radiation. In particular, within this approach it is evident that the endstate of evolution must be non-radiative (meaning vanishing flux of energy at future null infinity). In our toy model such non-radiative configurations are given by a static solution (called the half-kink) plus an alternating chain of N decoupled kinks and antikinks. We show numerically that the configurations N = 0 (static half-kink) and N = 1 (superposition of the static half-kink and the antikink which recedes to infinity) appear as generic attractors and we determine a codimension-one borderline between their basins of attraction. The rates of convergence to these attractors are analyzed in detail.
Blow-up of non-radial solutions for the L
2 critical inhomogeneous NLS equation
Authors: Cardoso Mykael , Farah Luiz Gustavo
Published: July 2022

We consider the L
2 critical inhomogeneous nonlinear Schrödinger equation in

R

N

i

∂

t

u
+
Δ
u
+
|
x

|

−
b

|
u

|

4
−
2
b

N

u
=
0
,

where N ⩾ 1 and 0 < b < min{2, N}. We prove that if

u

0

∈

H

1

(

R

N

)

satisfies E[u
0] < 0, then the corresponding solution blows-up in finite time. This is in sharp contrast to the classical L
2 critical nonlinear Schrödinger equation where this type of result is only known in the radial case for N ⩾ 2.
Justification of a nonlinear sixth-order thin-film equation as the reduced model for a fluid–structure interaction problem
Authors: Bukal Mario , Muha Boris
Published: July 2022

Starting from a nonlinear 2D/1D fluid–structure interaction problem between a thin layer of a viscous fluid and a thin elastic structure, in the vanishing limit of the relative fluid thickness, we rigorously derive a sixth-order thin-film equation describing the dynamics of vertical displacements of the structure. The procedure is essentially based on quantitative energy estimates in terms of the relative fluid thickness and a uniform no-contact result between the structure and the solid substrate. The sixth-order thin-film equation is justified in the sense of strong convergence of rescaled structure displacements to the unique positive classical solution of the thin-film equation. Moreover, the limiting fluid velocity and pressure can be expressed solely in terms of the solution to the thin-film equation.
Stirring speeds up chemical reaction
Authors: He Siming , Kiselev Alexander
Published: July 2022

We consider absorbing chemical reactions in a fluid flow modelled by the coupled advection–reaction–diffusion equations. In these systems, the interplay between chemical diffusion and fluid transportation causes the enhanced dissipation phenomenon. We show that the enhanced dissipation time scale, together with the reaction coupling strength, determines the characteristic time scale of the reaction.
Production and performance of a low temperature shape-memory actuator based on twisted-coiled spring mechanics
Authors: Jafari Horastani Sahar , Ghane Mohammad , Karevan Mehdi
Published: July 2022

Demand for new types of actuators continues to grow, and novel approaches have been made possible by the advent of new materials and fabrication strategies. Self-powered actuators have attracted significant attention owing to their ability to be driven by elements in ambient environments. This type of actuator can be used in flexible strain sensors, artificial muscles, soft robotics, and smart breathing textiles. However, petrochemical-based polymers are generally environmentally unfriendly and cause ecological problems. The use of biodegradable polymers is one of the preferred solutions to ecological problems. Polylactic acid is a biodegradable and biocompatible polymer with a high potential. In this study, nanoclay reinforced polylactic acid/thermoplastic polyurethane was used as a precursor. The yarn that was produced was highly twisted. The twisted yarn was then shaped into a coiled structure via mandrel annealing. An apparatus was designed to investigate the thermal actuation behavior of twisted-coiled yarn in an isometric state. The blocked force and free stroke were calculated in an isometric state by using linear material equations. The thermal actuation behavior of the twisted-coiled yarn was also studied in the isotonic state. This precursor exhibited a considerable two-way shape-memory effect in a twisted-coiled structure. It also showed a significant reversible contraction stroke within the low temperature range. The theoretical stroke was determined using two different models: the force–stroke equation and spring mechanics. The theoretical results were compared with the experimental results, which revealed acceptable agreement between the theoretical and experimental values.
Magnon-driven dynamics of frustrated skyrmion in synthetic antiferromagnets: effect of skyrmion helicity oscillation
Authors: Jin Z , Liu T T , Liu Y , Hou Z P , Chen D Y , Fan Z , Zeng M , Lu X B , Gao X S , Qin M H , Liu J-M
Published: July 2022

A theoretical study on the interplay of frustrated skyrmion and magnons should reveal new physics and future experiment designs. In this study, we investigate the magnon-driven dynamics of frustrated skyrmion in synthetic antiferromagnets based on micromagnetic simulations, focusing on the effect of skyrmion helicity oscillation. The oscillation speed and Hall angle of the frustrated skyrmion depending on the magnon intensity and damping constant are simulated, which demonstrates that the skyrmion helicity oscillation effectively suppresses Hall motion. The elastic scattering theory reveals that the helicity oscillation affects the scattering cross-section of injected magnons, which in turn effectively modulates the skyrmion Hall motion. This study provides a comprehensive understanding of magnon-skyrmion scattering in frustrated magnets, thus benefiting future spintronic and magnonic applications.
Tunable Brillouin-Raman multi-wavelength fiber laser with a linear cavity configuration
Authors: Zhou Zezhong , Yang Qian , Chen Yapeng , Chen Mengmeng , Zhang Zuxing
Published: July 2022

A tunable Brillouin-Raman multi-wavelength fiber laser has been proposed and demonstrated in a linear cavity configuration, where stimulated Raman scattering and stimulated Brillouin scattering occur simultaneously in the dispersion compensation fiber. The influence of Brillouin pump (BP) and Raman pump (RP) power on the obtained Brillouin Stokes lines has been investigated in detail. The experimental results show that when BP wavelength is 1545 nm, 63 orders of Stokes lines can be obtained at most, and the interval between adjacent lines is about 0.08 nm. Moreover, there are two opposite relations between the number of the generated Stokes lines and the BP power within the whole tunable range of 1520–1575 nm (55 nm), depending on the Raman gain. The proposed laser featuring simple structure will enable promising potentials in optical communications and optical sensor systems.
Comments on the mass sheet degeneracy in cosmography analyses
Authors: Teodori Luca , Blum Kfir , Castorina Emanuele , Simonović Marko , Soreq Yotam
Published: July 2022

We make a number of comments regarding modeling degeneracies in strong lensing measurements of the Hubble parameter H
0. The first point concerns the impact of weak lensing associated with different segments of the line of sight. We show that external convergence terms associated with the lens-source and observer-lens segments need to be included in cosmographic modeling, in addition to the usual observer-source term, to avoid systematic bias in the inferred value of H
0. Specifically, we show how an incomplete account of some line of sight terms biases stellar kinematics as well as ray tracing simulation methods to alleviate the mass sheet degeneracy.

The second point concerns the use of imaging data for multiple strongly-lensed sources in a given system.
We show that the mass sheet degeneracy is not fully resolved by the availability of multiple sources: some degeneracy remains because of differential external convergence between the different sources.

Similarly, differential external convergence also complicates the use of multiple sources in addressing the approximate mass sheet degeneracy associated with a local (“internal”) core component in lens galaxies. This internal-external degeneracy is amplified by the non-monotonicity of the angular diameter distance as a function of redshift.

For a rough assessment of the weak lensing effects, we provide estimates of external convergence using the nonlinear matter power spectrum, paying attention to non-equal time correlators.
QED effects on phase transition and Ruppeiner geometry of Euler-Heisenberg-AdS black holes*
Authors: Ye Xu , Chen Zi-Qing , Li Ming-Da , Wei Shao-Wen
Published: July 2022

Considering the quantum electrodynamics (QED) effect, we study the phase transition and Ruppeiner geometry of Euler-Heisenberg anti-de Sitter black holes in the extended phase space. For negative and small positive QED parameters, we observe a small/large black hole phase transition and reentrant phase transition, respectively, whereas a large positive value of the QED parameter ruins the phase transition. Phase diagrams for each case are explicitly shown. Then, we construct the Ruppeiner geometry in thermodynamic parameter space. Different features of the corresponding scalar curvature are shown for both the small/large black hole phase transition and reentrant phase transition cases. Of particular interest is the additional region of positive scalar curvature, indicating a dominant repulsive interaction among black hole microstructures, for the black hole with a small positive QED parameter. Furthermore, universal critical phenomena are observed for the scalar curvature of Ruppeiner geometry. These results indicate that the QED parameter has a crucial influence on the black hole phase transition and microstructure.
Entropic destruction of heavy quarkonium in a rotating hot and dense medium from holography*
Authors: Wu Ping-ping , Zhang Zi-qiang , Zhu Xiangrong
Published: July 2022

Previous studies have indicated that the peak of the quarkonium entropy at the deconfinement transition can be related to the entropic force, which would induce the dissociation of heavy quarkonium. In this study, we investigated the entropic force in a rotating hot and dense medium using AdS/CFT correspondence. It was found that the inclusion of angular velocity increases the entropic force, thus enhancing quarkonium dissociation, while chemical potential has the same effect. The results imply that the quarkonium dissociates easier in rotating medium compared with the static case.
Intensity dependence of sub-harmonics in cortical response to photic stimulation
Authors: Phogat Richa , Parmananda P , Prasad Ashok
Published: July 2022

Objective. Periodic photic stimulation of human volunteers at 10 Hz is known to entrain their electroencephalography (EEG) signals. This entrainment manifests as an increment in power at 10, 20, 30 Hz. We observed that this entrainment is accompanied by the emergence of sub-harmonics, but only at specific frequencies and higher intensities of the stimulating signal. Thereafter, we describe our results and explain them using the physiologically inspired Jansen and Rit neural mass model (NMM). Approach. Four human volunteers were separately exposed to both high and low intensity 10 Hz and 6 Hz stimulation. A total of four experiments per subject were therefore performed. Simulations and bifurcation analysis of the NMM were carried out and compared with the experimental findings. Main results. High intensity 10 Hz stimulation led to an increment in power at 5 Hz across all the four subjects. No increment of power was observed with low intensity stimulation. However, when the same protocol was repeated with a 6 Hz photic stimulation, neither high nor low intensity stimulation were found to cause a discernible change in power at 3 Hz. We found that the NMM was able to recapitulate these results. A further numerical analysis indicated that this arises from the underlying bifurcation structure of the NMM. Significance. The excellent match between theory and experiment suggest that the bifurcation properties of the NMM are mirroring similar features possessed by the actual neural masses producing the EEG dynamics. NMMs could thus be valuable for understanding properties and pathologies of EEG dynamics, and may contribute to the engineering of brain–computer interface technologies.
Thermodynamic symmetry resolved entanglement entropies in integrable systems
Authors: Piroli Lorenzo , Vernier Eric , Collura Mario , Calabrese Pasquale
Published: July 2022

We develop a general approach to compute the symmetry-resolved Rényi and von Neumann entanglement entropies (SREE) of thermodynamic macrostates in interacting integrable systems. Our method is based on a combination of the thermodynamic Bethe ansatz and the Gärtner–Ellis theorem from large deviation theory. We derive an explicit simple formula for the von Neumann SREE, which we show to coincide with the thermodynamic Yang–Yang entropy of an effective macrostate determined by the charge sector. Focusing on the XXZ Heisenberg spin chain, we test our result against iTEBD calculations for thermal states, finding good agreement. As an application, we provide analytic predictions for the asymptotic value of the SREE following a quantum quench.
The review of methods for a real-time monitoring and forecasting bird strike risk level
Authors: Szafrański B , Zieja M , Wójcik J
Published: July 2022

A high level of flight safety is a priority for all aviation organizations in the world. The negative impact of the natural environment on air operations is one of the most common factors causing the situations exerting a negative influence on flight safety (in short-aviation occurrence) in the Polish Army. The most common reason of the aviation occurrence connected with the environment area is the bird strike. The lack of a method for real-time monitoring and forecasting bird strike risk level is a significant gap in the proactive approach to flight safety within the Polish Air Force. The article presents a review of the methods for monitoring and forecasting the intensity of bird movements, which were used to build advisory systems used by air forces of the United States, Germany, the Netherlands, Belgium and Israel. The article consists of summary of most important properties of the methods and analysis in terms of their applicability in the Polish conditions. Particular attention was paid to the complicated network of routes of bird species occurring on Polish territory. Finally, after proving the incomplete usefulness of the above-mentioned methods in Polish conditions, the need to develop a more adequate method was justified.
Parallel Processes Planning using Computer Supporting System
Authors: Gwiazda A , Kalinowski K , Bączkowicz M
Published: July 2022

Planning the structure of operation taking into account the dynamical contemporary market is one of the most serious challenges for industry in the XXI century. It is particularly complex and complicated especially for the multi-process scheduling that is characteristic for modern large industrial plants. The method allowing solving the mentioned problem should be based on the analysis of constraints as any manageable system is limited in achieving its goals by a number of constraints. The most important of these is resource availability. Taking into account the critical resources chain it is possible to create complex schedules in multi-process environments. In the paper is presented analysis of results, obtained for such conditions, using original application adding the process of scheduling.
Design of Corrective Inserts for Patients with Feet Dysfunctions With Reverse Engineering Techniques
Authors: Wrześniowska K , Grabowik C , Sękala A
Published: July 2022

These days CAD systems are successfully used in medicine and orthopaedics. Nevertheless, there is still a need of developing of an efficient methodology of their use in case of designing of products which fulfil patient’s requirements according to their disabilities and faulty postures. The cognitive goal of the presented work was disposure to answer the question whether? And how reverse engineering techniques would enable the design of an orthopaedic inserts for people with static flat-valgus foot. The accomplishment of the research problem defined in such a way required working out of solutions for the following detailed research problems: in which way and how to make feet casts to get the precise models – the input data for the 3D scanning process, which 3D scanning technique to apply, taking into consideration available technical means, and how to determine the placement distance of the corrective element for the designed correction insert. The main research areas encompassed inter alia: interviewing the potential patient and examining of their lower limb, making of feet pedographs, creating of feet casts negatives, preparing of casts for 3D scanning, models digitization, and feet inserts design.
Automated Design and Rapid Manufacturing of Low-Cost Customized Upper Limb Prostheses
Authors: Gགྷrski Filip , Zawadzki Przemyslaw , Wichniarek Radoslaw , Kuczko Wieslaw , Slupińska Sandra , Żukowska Magdalena
Published: July 2022

The paper presents results of studies on an innovative approach to mass customization of prostheses, namely automated design and rapid manufacturing (3D printing), on the basis of 3D scanning of upper limb of a given patient. Two different products are presented – a simple mechanical prosthesis and a cosmetic prosthesis. In both cases, intelligent CAD models, with adaptive geometry – changing automatically to the data from 3D scanning – were prepared. The digital models were built and tested using data of real patients. A special algorithm of 3D scanning data processing was prepared and implemented, as well as a set of algorithms of automated data processing for 3D printing processes. The test models were manufactured using low-cost 3D printing technology. The verification was successful – possibility of preparing customized prostheses was reached, using automated design.
Intelligent manufacturing templates for CNC machine programming
Authors: Kowalski M , Zawadzki P
Published: July 2022

The main purpose of the work is to present the method of preparing special production templates in the CAM program assuming the automation of CNC machine programming. The template is developed according to the unique ACPUT method - automatic CAM programming using machining templates, consisting of a combination of knowledge engineering and special CAM program tools to minimize the time during the design of the technological process. In developing the templates, the ontology of the technological process in the field of milling machining used in the selected enterprise was used. The effectiveness of the automatic programming process of CNC machines using production templates has been described, on the example of the process of manufacturing matrix tooling used in the welding process.
Mechanical, microstructural and electrical properties of Al7075/SiC based hybrid composites with nano B4C, Graphene and CNT reinforcements
Authors: Ajithkumar J P , Anthony Xavior M
Published: July 2022

Superfluous properties of Graphene and CNT reinforced composites are making significant revolution in the application area of metal matrix nano-composites. Fabrication of these composites without any flaw is the challenging task due to its inherent properties such as limited wettability, unique structure, load transfer efficiency, shape and size. The individual reinforcements such as 0.1wt.% B4C, 0.1wt.% Graphene and 0.1wt.% CNT were successfully incorporated in common Al7075/10wt.% SiC base through squeeze casting method combined with ultrasonic vibration. The influence of reinforcements on the mechanical, metallurgical and electrical properties of the composites was analysed in this study. The hardness value of the B4C-based, Graphene-based and CNT-based composites has enhanced to 167 BHN, 145 BHN and 135 BHN respectively from the base matrix. Tensile strength has also improved to 239 MPa, 324 MPa and 308 MPa. In the case of micro-structural characteristics, the addition of Graphene in the Graphene reinforced composite improved the grain structure due to the grain refining effect followed by the CNT and B4C reinforced composites with the similar weight fraction and processing methods. The influence of various reinforcements was analysed using Optical Microscope (OM), Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray analysis (EDX) techniques. Addition of Graphene and CNT increased the electrical conductivity of respective composites to 24.2 MS/m and 21.1 MS/m.
Workstation Modelling with Poka Yoke and Ergonomics Rules in Tecnomatix Jack Human Simulation
Authors: Grabowik C , Gwiazda A , Ćwikla G , Kalinowski K , Byrtek A
Published: July 2022

The purpose of the presented work was to conduct a case study of a control station modelling taking into consideration Poka-Yoke and ergonomics rules in Tecnomatix Jack Human Simulation. At the beginning a subject of interest of the modelling process was chosen. In the presented case the piece being produced in the modelled workstation was a component of a bicycle gear; it is a gear hook. Next, the worker’s characteristics were defined, and the picture of the 8 hour-long working shifts was taken. Basis on this, the model of the workstation which fulfils human factors and ergonomics requirements in Siemens NX system was modelled. Subsequently the ergonomics analysis was conducted both manually and with Tecnomatix Jack Human Simulation. The subjected analysis was carried out with OWAS and Lehman methods inter alia. Thanks to conducting the ergonomic analysis in the two ways it was possible to make a comparative analysis of the achieved results.