bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing compliments in Face-to-Face vs. online interactions among Iranian speakers of Persian
Authors: Derakhshan Ali , R. Eslami Zohreh , Shakki Farzaneh
Published: June 2023

There has been ongoing research contrasting online vs. Face-To-Face (FTF) interactions for more than a decade.
This study fills the gap in the literature considering FTF vs. online contexts by comparing the norms and patterns of
complimenting in Persian and explores the complimenting strategies, syntactic patterns, and internal and external modifiers used
in each setting. The corpus included 366 FTF compliments related to the topic of appearance. Findings demonstrated that in both
settings explicit and formulaic compliments are used more frequently than implicit and non-formulaic ones. However, implicit
compliments in FTF interactions were less prevalent than those in online settings. FTF compliments did not show the same level of
creativity as the online ones did and a more diverse set of adjectives were used in online vs FTF compliments. Finally, the paper
provides implications for further research.
Hydro-political power of the Nile
Authors: El Shazly Reham , El Falaky May Samir
Published: June 2023

This study examines cognitive representations of Ethiopia and Egypt’s hydro-political stances on the Grand
Ethiopian Renaissance Dam. Data were analysed using image schema theory and conceptual metaphor theory to identify how political
leaders deploy conceptual structures to construct, maintain, and reproduce (counter-)hydro-hegemony for water management and
international relations broadly. Results suggest that the gerd represents physical and symbolic boundaries
constructed/activated to block and animate power. Egypt prefers multilateralism on gerd matters; whereas,
Ethiopia acts unilaterally in its national interest. The findings indicate that international public opinion can be cognitively
and discursively manipulated to legitimise (in)action sanctioning (counter)hydro-hegemony using original metaphor mappings and
mini-narratives. This study posits that interstate hydro-disputes can be viewed as either a journey or trial.
While Egypt suggested a family-threat-journey-destination script where all regions correlate to garner power, Ethiopia
invoked a victim -threat-defendant-plaintiff-trial narrative to defend confrontational move(s) and motivate the
illegitimate jury to dismiss the case.
Metaphorical Pattern Analysis and MIPVU combined
Authors: Muelas-Gil María
Published: June 2023

One of the constant debates within conceptual metaphors studies and metaphor in discourse concerns metaphor
identification and annotation. In recent years, most metaphor studies have applied Steen et al.’s MIPVU or Pragglejazz’s MIP as
the identification method, but this does not mean that they are exclusive. In fact, there are certain factors of a given study
that influence the choice of one method over another, such as its design, size or language. It was precisely the particularities
of our corpus (made of economic reports published in English and Spanish) that suggested the combination of other existing methods
in order to obtain, in the most practical way, the most reliable outcomes for this target-based case study. Stefanowitsch’s MPA
was applied and complemented with MIPVU, used to filter and confirm potentially metaphorical patterns. Apart from reviewing some
of the existing methods, this paper provides a case study that supports the validity of combining identification methods or
adapting them to the needs of each case, as the results obtained after analysis show concordance and agreement
post-combination.
Comparison of thermomechanical responses of single-arc and dual-arc parallel additive manufacturing
Authors: Wu Qianru , Tang Wenlai , Yang Jiquan , Shi Xuezhi
Published: June 2023

Printed metallic parts often suffer from thermomechanical defects such as delamination, buckling and warping, and this effect is exacerbated in multi-arc additive manufacturing (AM) due to the extensive heat input and large molten pool. These defects originate primarily because of high residual stresses accumulated during layer-by-layer deposition. Here we develop, validate and employ a three-dimensional finite element model with two independent heat sources to analyse the thermomechanical responses in dual-arc parallel AM of Ti6Al4V thin-walled parts. The results are compared with those of the conventional single-arc AM. Although the deformation in dual-arc AM is slightly larger than that in single-arc AM, the stresses at the substrate-deposit interface for dual-arc AM are reduced by 53% due to the lower cooling rate.
Resistance exercise training augments the immunomodulatory adaptations to aerobic high‐intensity interval training
Authors: Soltani Nakisa , Marandi Sayyed Mohammad , Hovsepian Volga , Kazemi Mohammad , Esmaeil Nafiseh
Published: June 2023

To compare the effectiveness of different types of high‐intensity interval training (HIIT) on meta‐inflammation during obesity, TLR4 pathway activities were assessed following a 10‐week randomized trial. 30 young females with overweight and obesity were randomly allocated to aerobic HIIT (HIIT/AE) or resistance exercise in HIIT (HIIT/RE) and performed a 28‐minute (4 × 4 min) in each session. During each interval, the HIIT/AE performed four minutes of all‐extremity cycling, whereas the HIIT/RE completed four minutes of combined resistance exercises and all‐extremity cycling. The TLR4 pathway gene expression was measured for the TLR4 receptor, downstream adaptors (TIR domain‐containing adaptor‐inducing interferon‐β (TRIF) and myeloid differentiation factor (MYD) 88), transcriptional factors (nuclear factor kappa B (NF‐κB), and interferon regulatory factor (IRF) 3), and its negative regulator (tumor necrosis factor (TNF) a‐induced protein 3 (TNFAIP3)). The serum levels of TNFα, interferon (IFN) γ, interleukin (IL)‐10, and adiponectin were measured. We found that TLR4 (HIIT/RE: 0.6 ± 0.43 vs. HIIT/AE: 1.24 ± 0.82, p = 0.02), TRIF (HIIT/RE: 0.51 ± 0.4 vs. HIIT/AE: 3.56 ± 0.52, p = 0.001), and IRF3 (HIIT/RE: 0.49 ± 0.42 vs. HIIT/AE: 0.6 ± 0.89; p = 0.04) levels were significantly downregulated in HIIT/RE compared to the HIIT/AE, with a significant reduction in serum levels of TNFα (pg/ml) (HIIT/RE: 22.5 ± 11.3 to 6.3 ± 5.3 vs. HIIT/AE: 19.16 ± 20.8 to 13.48 ± 21.7, p = 0.04) and IFNγ (pg/ml) (HIIT/RE: 43.5 ± 20.6 to 37.5 ± 4.3 vs. HIIT/AE: 37.6 ± 5.6 to 68.1 ± 22.5, p = 0.03). Adiponectin and IL‐10 levels did not significantly differ between the two groups. Thus, resistance exercise training augments the immunomodulatory adaptations to HIIT and should be prescribed to people at risk of cardiometabolic disease.

Highlights

HIIT in combination with resistance exercise looks more effective than HIIT alone to target TLR4‐mediated inflammation in individuals with overweight and obesity.

HIIT/RE induces a different effect on two downstream cascades of TLR4, leading to a greater overall reduction of TRIF‐dependent pathway activities compared to MYD88.

Both HIIT protocols show comparable effects on the negative regulatory protein TNFAIP3 gene expression.
Modelling the emergence of cosmic anisotropy from non-linear structures
Authors: Anton Theodore , Clifton Timothy
Published: June 2023

Astronomical observations suggest that the Universe may be anisotropic on the largest scales. In order to model this situation, we develop a new approach to cosmology that allows for large-scale anisotropy to emerge from the growth of non-linear structure. This is achieved by decomposing all relevant fields with respect to a preferred space-like direction, and then averaging the resulting scalar quantities over spatial domains. Our approach allows us to derive a set of large-scale effective field equations that govern the dynamics of any emergent large-scale anisotropy, and which (up to back-reaction terms) take the form of the field equations of the locally rotationally symmetric Bianchi cosmologies. We apply our approach to the dust-filled Farnsworth solutions, which are an interesting set of exact cosmological models that allow for both anisotropic expansion and large-scale bulk flow.
On the horizon area of effective loop quantum black holes
Authors: Sobrinho F C , Borges H A , Baranov I P R , Carneiro S
Published: June 2023

Effective models of quantum black holes inspired by loop quantum gravity (LQG) have had success in resolving the classical singularity with polymerisation procedures and by imposing the LQG area gap as a minimum area. The singularity is replaced by a hypersurface of transition from black to white holes, and a recent example is the Ashtekar, Olmedo and Singh (AOS) model for a Schwarzschild black hole. More recently, a one-parameter model, with equal masses for the black and white solutions, was suggested by Alonso-Bardaji, Brizuela and Vera (ABBV). An interesting feature of their quantisation is that the angular part of the metric retains its classical form and the horizon area is therefore the same as in the classical theory. In the present contribution we solve the dynamical equations derived from the ABBV effective Hamiltonian and, by applying the AOS minimal area condition, we obtain the scaling of the polymerisation parameter with the black hole mass. We then show that this effective model can also describe Planck scale black holes, and that the curvature and quantum corrections at the horizon are small even at this scale. By generating the exterior metric through a phase rotation in the dynamical variables, we also show that, for an asymptotic observer, the Kretschmann scalar is the same as in the classical Schwarzschild solution, but with a central mass screened by the quantum fluctuations.
Crystal orientation dependent spin pumping in a Bi0.1Y2.9Fe5O12/Pt interface
Authors: Gurjar Ganesh , Sharma Vinay , De Avirup , Nair Sunil , Patnaik S , Kuanr Bijoy K
Published: June 2023

Ferromagnetic resonance (FMR) based spin pumping is a versatile tool to quantify the spin-mixing conductance and spin-to-charge conversion (S2CC) efficiency of ferromagnet–normal metal (FM/NM) heterostructures. The spin-mixing conductance at the FM–NM interface can also be tuned by the crystal orientation symmetry of epitaxial FM. In this work, we study the S2CC in epitaxial bismuth-substituted yttrium iron garnet (Bi0.1Y2.9Fe5O12) thin-film Bi–YIG (100 nm) interfaced with heavy metal platinum (Pt, 8 nm) deposited by pulsed laser deposition on different crystal orientations of Gd3Ga5O12 substrates, i.e. [100] and [111]. The crystal structure and surface roughness characterized by x-ray diffraction and atomic force microscopy measurements establish epitaxial Bi–YIG [100] and Bi–YIG [111] orientations, and atomically flat surfaces, respectively. The S2CC quantification was realized using two complementary techniques, namely (i) FMR-based spin pumping and the inverse spin Hall effect (ISHE) at GHz frequencies and (ii) temperature-dependent spin Seebeck measurements. The FMR-ISHE results demonstrate that the [111]-oriented Bi–YIG/Pt sample shows significantly higher values of spin mixing conductance ((2.31 ± 0.23) × 1018 m−2) and spin Hall angle (0.01 ± 0.001) as compared to the [100]-oriented Bi–YIG/Pt. Longitudinal spin Seebeck measurements reveal that the [111]-oriented sample has a higher spin Seebeck coefficient (106.40 ± 10 nV mm−1 K−1). The anisotropic nature of the spin-mixing conductance and spin Seebeck coefficient in the [111] and [100] orientations are discussed using the magnetic environment elongation along the surface normal or parallel to the growth direction. Our results aid in understanding the role of crystal orientation symmetry in S2CC-based spintronics devices.
Reciprocal space temperature-dependent phonons method from ab-initio dynamics
Authors: Garba Ibrahim Buba , Morresi Tommaso , Bouillaguet Charles , Casula Michele , Paulatto Lorenzo
Published: June 2023

We present a robust reciprocal-space implementation of the temperature-dependent effective potential method, our implementation can scale easily to large cell and long sampling time. It is interoperable with standard ab-initio molecular dynamics and with Langevin dynamics. We prove that both sampling methods can be efficient and accurate if a thermostat is used to control temperature and dynamics parameters are used to optimize the sampling efficiency. By way of example, we apply it to study anharmonic phonon renormalization in weakly and strongly anharmonic materials, reproducing the temperature effect on phonon frequencies, crossing of phase transition, and stabilization of high-temperature phases.
Enhanced toluene gas-sensing properties of MEMS sensor based on Pt-loaded SnO2 nanoparticles
Authors: Liu Xiaofan , Zhao Jian , Wang Yongguang , Hu Yan , Xu Linjie , Yao Longchao , Zheng Chenghang , Yang Jian , Gao Xiang
Published: June 2023

Rapid detection of low concentration toluene is highly desirable in environment monitoring, industrial processes, medical diagnosis, etc. In this study, we prepared Pt-loaded SnO2 monodispersed nanoparticles through hydrothermal method and assembled a sensor based on micro-electro-mechanical system (MEMS) to detect toluene. Compared with the pure SnO2, the 2.92 wt% Pt-loaded SnO2 sensor exhibits a 2.75 times higher gas sensitivity to toluene at about 330 °C. Meanwhile, the 2.92 wt% Pt-loaded SnO2 sensor also has a stable and good response to 100 ppb of toluene. Its theoretical detection limit is calculated as low as 12.6 ppb. Also, the sensor has a short response time of ∼10 s to different gas concentrations, as well as the excellent dynamic response—recovery characteristics, selectivity, and stability. The improved performance of Pt-loaded SnO2 sensor can be explained by the increase of oxygen vacancies and chemisorbed oxygen species. The electronic and chemical sensitization of Pt to SnO2-based sensor, together with small size and fast gas diffusion of the MEMS design ensured fast response and ultra-low toluene detection. This provides new ideas and decent prospect for developing miniaturized, low-power-consumption, and portable application of gas sensing devices.
Global wellposedness of the 3D compressible Navier–Stokes equations with free surface in the maximal regularity class
Authors: Shibata Yoshihiro , Zhang Xin
Published: June 2023

This paper concerns the global well posedness issue of the compressible Navier–Stokes equations (CNS) describing barotropic compressible fluid flow with free surface occupied in the three dimensional exterior domain. Combining the maximal L

p
-L

q
estimate and the L

p
-L

q
decay estimate of solutions to the linearized equations, we prove the unique existence of global in time solutions in the time weighted maximal L

p
-L

q
regularity class for some p > 2 and q > 3. Namely, the solution is bounded as L

p
in time and L

q
in space. Compared with the previous results of the free boundary value problem of (CNS) in unbounded domains, we relax the regularity assumption on the initial states, which is the advantage by using the maximal L

p
-L

q
regularity framework. On the other hand, the equilibrium state of the moving boundary of the exterior domain is not necessary the sphere. To our knowledge, this paper is the first result on the long time solvability of the free boundary value problem of (CNS) in the exterior domain.
Direct visualization of relativistic Coulomb field in the near and far field ranges
Authors: Galletti M , Cianchi A , Curcio A , Dipace F , Ferrario M , Pompili R
Published: June 2023

Coherent emission coming from relativistic charged bunches is of great interest in a wide range of user-oriented applications and high-resolution diagnostics. The complete characterization of such emission is therefore important in view of a complete understanding of its potential. Here we present a complete temporally-resolved characterization of the radiation emitted by ultra-short relativistic electron bunches using a temporal diagnostic based on electro-optical sampling with a few tens fs of temporal resolution. We have characterized, for the first time to our knowledge, the evolution of the radiation (in THz range) both in amplitude and direction of propagation by varying the detection (i.e. the observer) position from the near to the far field (FF) range. Results show that in the near-field regime the emitted radiation propagates collinearly with the electron beam; while, approaching the FF regime, the radiation behaves as the classical Cherenkov radiation.
Atomistic removal mechanisms of nano polishing single-crystal SiC in hydroxyl free radical aqueous solution
Authors: Yuan Zewei , Tang Meiling , Wang Ying , Sun Jingting , He Yan
Published: June 2023

Single-crystal SiC has been widely applied for electronic devices. Photocatalysis assisted chemical mechanical polishing (PCMP) is an efficient global flattening technology for finishing SiC, but the atomic level removal mechanism is still under discussion. In this paper, the atomic behavior of removal with hydroxyl free radical (·OH) aqueous solution was investigated using the ReaxFF molecular dynamics (MD) simulation. The theoretical analysis shows that ·OH oxidation of SiC can occur spontaneously, and the mechanical behavior would be able to increase the potential energy and reduce the reaction barrier the reactants. The simulation results show that with only chemical oxidation occurs, the SiC surface adsorbed O, H or -OH to produce Si-O*H2, Si-OH2, Si-OH, Si-H2O, Si-H*O*-H2O, Si-H2O*, Si-O*H* and Si-H, etc, no Si atoms were observed to detach from the SiC substrate. Nevertheless, if the mechanical action was applied, some Si and C atoms break off the substrate by forming SiO, SiO2, CO, CO2 or chain, and the other Si or C atoms were detached by the adsorption on the abrasive. In addition, no atoms break away from the substrate in H2O solution. The force F

x
in H2O solution is less than that in ·OH aqueous solution because of the lubrication of H2O solution. Furthermore, it is found that the mechanical action applied, the more -H and -O adsorbed on the SiC surface result in the more Si and C atoms are removed. The experimental results show that SiC wafer could be oxidized by ·OH under the mechanical action of diamond abrasive particles. This study reveals that the removal of Si and C atoms from the substrate is the result of the combined action of chemical oxidation and mechanical sliding, which is helpful to explain the dynamic process of the oxidation and removal of Si and C atoms on the atomic level in the SiC PCMP. Furthermore, it provides a valuable method reveal the material removal mechanism.
Effect of chirp on stimulated-forward Raman scattering in a magnetised plasma with rippled density for fusion applications
Authors: Kamboj Oriza , Gupta Devki Nandan , Kant Niti
Published: June 2023

Stimulated Raman scattering (SRS) is one of the mechanisms limiting power scaling in inertial confinement fusion (ICF). In this work, we demonstrate the effective suppression of SRS by the combined effects of static density fluctuations and an azimuthal magnetic field with a propagating chirped laser pulse. In the presence of an azimuthal magnetic field, chirped laser pulse propagates through a density-rippled plasma and undergoes stimulated-forward Raman scattering (SFRS), resulting in two radially localized electromagnetic sidebands waves and a lower-hybrid wave. Absolute and growing modes saturate due to ion density fluctuations, which then suppress instability growth through mode coupling. The modes modified by the combined effect of chirp and azimuthal magnetic field are effectively damped after saturation. As a result, the overall growth rate of the instability reduces. The comparison of positive and negative chirp demonstrated that when a positive chirp is being used, instability is more effectively suppressed. Based on non-local theory, we have analyzed the growth of the SFRS for positive and negative chirp and estimated it for ICF-relevant parameters and observed the effect of the growth rate.
Approximate simulation of cortical microtubule models using dynamical graph grammars
Authors: Medwedeff Eric , Mjolsness Eric
Published: June 2023

Dynamical graph grammars (DGGs) are capable of modeling and simulating the dynamics of the cortical microtubule array (CMA) in plant cells by using an exact simulation algorithm derived from a master equation; however, the exact method is slow for large systems. We present preliminary work on an approximate simulation algorithm that is compatible with the DGG formalism. The approximate simulation algorithm uses a spatial decomposition of the domain at the level of the system’s time-evolution operator, to gain efficiency at the cost of some reactions firing out of order, which may introduce errors. The decomposition is more coarsely partitioned by effective dimension (d = 0 to 2 or 0 to 3), to promote exact parallelism between different subdomains within a dimension, where most computing will happen, and to confine errors to the interactions between adjacent subdomains of different effective dimensions. To demonstrate these principles we implement a prototype simulator, and run three simple experiments using a DGG for testing the viability of simulating the CMA. We find evidence indicating the initial formulation of the approximate algorithm is substantially faster than the exact algorithm, and one experiment leads to network formation in the long-time behavior, whereas another leads to a long-time behavior of local alignment.
Main Sequence Star Super-flare Frequency based on Entire Kepler Data
Authors: Althukair A. K. , Tsiklauri D.
Published: June 2023

We wrote and used an automated flare detection Python script to search for super-flares on main sequence stars of types A, F, G, K and M in Kepler’s long-cadence data from Q0 to Q17. We studied the statistical properties of the occurrence rate of super-flares. For the G-type data set, we compared our results with the previous results of Okamoto et al. by splitting the data set into four rotational bands. We found similar power-law indices for the flare frequency distribution. Hence, we show that inclusion of a high-pass filter, sample biases, gyrochronology and completeness of flare detection is of no significance, as our results are similar to those of Okamoto et al. We estimated that a super-flare on G-type dwarfs with energy of 1035 erg occurs on a star once every 4360 yr. We found 4637 super-flares on 1896 G-type dwarfs. Moreover, we identified 321, 1125, 4538 and 5445 super-flares on 136, 522, 770 and 312 dwarfs of types A, F, K and M, respectively. We ascertained that the occurrence rate (dN/dE) of super-flares versus flare energy, E, shows a power-law distribution with

dN

/

dE
∝

E

−
α

, where α ≃ 2.0 to 2.1 for the spectral types from F-type to M-type stars. In contrast, the obtained α ≃ 1.3 for A-type stars suggests that the flare conditions differ from those of the other spectral-type stars. We note an increase in flare incidence rate in F-type to M-type stars and a decrease in A-type to F-type stars.
A scoping review of current and emerging techniques for evaluation of peripheral nerve health, degeneration, and regeneration: part 1, neurophysiology
Authors: Mandeville Ross , Sanchez Benjamin , Johnston Benjamin , Bazarek Stanley , Thum Jasmine A , Birmingham Austin , See Reiner Henson B , Leochico Carl Froilan D , Kumar Viksit , Dowlatshahi Arriyan S , Brown Justin , Stashuk Daniel , Rutkove Seward B
Published: June 2023

Peripheral neuroregeneration research and therapeutic options are expanding exponentially. With this expansion comes an increasing need to reliably evaluate and quantify nerve health. Valid and responsive measures that can serve as biomarkers of the nerve status are essential for both clinical and research purposes for diagnosis, longitudinal follow-up, and monitoring the impact of any intervention. Furthermore, such biomarkers can elucidate regeneration mechanisms and open new avenues for research. Without these measures, clinical decision-making falls short, and research becomes more costly, time-consuming, and sometimes infeasible. As a companion to Part 2, which is focused on non-invasive imaging, Part 1 of this two-part scoping review systematically identifies and critically examines many current and emerging neurophysiological techniques that have the potential to evaluate peripheral nerve health, particularly from the perspective of regenerative therapies and research.
Anchored advected interfaces, Oslo model, and roughness at depinning
Authors: Shapira Assaf , Jörg Wiese Kay
Published: June 2023

There is a plethora of one-dimensional advected systems with an absorbing boundary: the Toom model of anchored interfaces, the directed exclusion process where in addition to diffusion particles and holes can jump over their right neighbour, simple diffusion with advection, and Oslo sandpiles. All these models share a roughness exponent of

ζ
=
1

/

4

, while the dynamic exponent z varies, depending on the observable. We show that for the first three models z = 1, z = 2, and

z
=
1

/

2

are realized, depending on the observable. The Oslo model is apart with a conjectured dynamic exponent of

z
=
10

/

7

. Since the height in the latter is the gradient of the position of a disordered elastic string, this shows that

ζ
=
5

/

4

for a driven elastic string at depinning.
Adaptive Enhancement of High Greyscale Weld Images Based on the New Pixel Self-transformation Method
Authors: Li Liangliang , Ren Jia , Lv Zhigang , Gao Hui
Published: June 2023

X-ray nondestructive testing technology is widely used in the weld detection of oil and gas pipeline industry. The industrial welding manufacturing field produces 12-bit and higher high grey scale images that cannot be displayed directly on an 8-bit display. In this paper, we propose an adaptive pixel self-transformation method for high greyscale weld images. The method takes into account the characteristics of weld images and human perception. Firstly, a high dynamic range tone mapping model is designed, which converts the original RAW data into optical observable data. Secondly, in order to solve the problem that the traditional pixel self-transformation method can only adapt to the input with 256 levels of greyscale and cannot process the high-bit image data. An adaptive high-bit pixel self-transformation is proposed. Finally, the method of this paper was tested on 12-bit X-ray films. The experimental results show that the designed method, which improves the recognizability of weld images and can effectively obtain weld images with outstanding details, is an efficient weld feature enhancement algorithm.
Influence of Hob Front Angle on Grinding Wheel Curved Shapes in Open Edge Grinding
Authors: Yang Peiyou , Wang Xiaoli , Zhang Bo , Yang Shaofei
Published: June 2023

When calculating the grinding wheel curved shapes, the hob front angle of hob is usually zero by default. In the actual production and processing, there are many hobs whose hob front angle is not zero. In this paper, when calculating the grinding wheel curved shapes, the parameter hob front angle is added to analyze its influence on the grinding wheel curved shapes according to the grinding wheel curved shapes calculated by different hob front angles.
Simulation Study on Microstructure of Magnetic Field Assisted ECAM
Authors: Li Liangliang , Ma Baoji , Cao Jinkui , Chen Bangbang , Li Zhichao
Published: June 2023

Electrochemical additive manufacturing (ECAM) technology is a non-thermal metal additive manufacturing technology that is widely used in microfabrication. The quality of additively manufactured moulded parts can be improved by applying magnetic fields with unknown effects of process parameters on additively manufactured microstructures. Therefore, a multi-physical field coupling model for magnetic field-assisted ECAM was developed. The results show that increasing the applied voltage and magnetic field strength can increase the cathode current density and improve the deposition rate and deposition height, but after the applied voltage increases to 4 V, the ion concentration decreases too fast and the concentration polarization occurs, which affects the deposition rate instead. The ion flux reached the maximum at the magnetic field strength of 0.2T. However, the cathode current density is affected by the electrode gap, and the deposition rate decreases with the increase of the electrode gap, and the deposition rate stabilizes after the electrode gap increases to 50 μm. The increase in current density with increasing electrode size may be related to the applied magnetic field.
Study on Hydrophobic Surface of Magnesium Alloy Prepared by Femtosecond Laser and its Corrosion Resistance
Authors: Cao Jinkui , Ma Baoji , Li Liangliang , Li Xiangyu
Published: June 2023

Due to their excellent barrier and shielding effects, superhydrophobic magnesium alloy surfaces are increasingly interested in corrosion protection. This paper proposes a method for producing a stable superhydrophobic surface by laser scanning ablation of AZ31B magnesium alloy on its surface. The prepared layered micro-nanoemulsion convex structure with a lotus-like surface exhibited excellent superhydrophobicity after modification by stearic acid, and the static water droplet contact angle reached 163°. After 90 days in outdoor air, droplet pressure-based experiments show that the superhydrophobic surface possesses a long-term stable Cassie state. In addition, The superhydrophobic surface showed excellent corrosion resistance against magnesium alloy in a Neutral 3.5 wt.% NaCl solution. The results of the dynamic potential polarization tests showed that the existence of a gas layer cavity on the lotus-like surface structure caused the corrosion current density of superhydrophobic AZ31B (3.86±1 uA/cm2) to decrease by 2 orders of magnitude compared with that of the extruded AZ31B (103±1 uA/cm2). We believe the proposed method is simple, efficient, and non-polluting, especially for medical magnesium alloys in the field of in vivo implant materials to slow down corrosion and promote clinical applications.
Thermodynamic Properties of the Textured Brake System Considering Multi-factor
Authors: Li Jiachen , Li Junning
Published: June 2023

The thermodynamic properties are related to the life of the brake system. The texturing technology is introduced into the brake system to construct different groove textures on the brake pad. The influence of multi-factor conditions on the thermodynamic properties of the brake systems is studied based on the Finite Element Method. The results suggest that the horizontal groove texture on the brake disc can make the temperature field and stress field distribution more uniform. With the increase in braking pressure and car speed, the thermodynamic properties of the brake disc show an upward trend. The temperature difference of the brake disc is less than 3°C. It is found that the construction of appropriate groove texture of the brake pad helps improve the working performance of the car brake system.
Lightweight Design of Shell Based on Finite Element Method
Authors: Cao Yu , Jia Feng , Gao Pan , Cao Yan
Published: June 2023

The shell structure design of modern spacecraft internal devices is developing towards lightweight, high-performance, and low-cost. In order to achieve a lightweight construction of the shell structure, this work takes the spacecraft shell as an optimization object. Under the premise of ensuring that the stiffness of the box meets the design requirements, the lightweight construction of the box adopts a post-design optimization method. First, the preliminary design of the model was conducted using SolidWorks, and then the transient dynamic analysis of the model was conducted. The results met the design requirements. Then, the topology of the model is optimized using ANSYS Workbench software, and the optimization results are improved based on assembly conditions. Finally, a transient dynamic analysis of the topology optimized model was performed and compared with previous results. It was found that the design requirements were still met, while the weight was reduced by about 36.8%. This achieved lightweight design of the shell, improved performance, and reduced costs.
Analysis of Milling Force and Optimization of Milling Trajectory for the NC Machining of Small Integral Impeller
Authors: Yao Hui , Li Jinpei , Bai Yu , Wang Zhiji
Published: June 2023

In order to reduce the deformation of small integral impeller and improve the surface quality of blade in the process of NC machining, the influence of trajectory parameters on the milling force in the process of impeller NC finishing is studied and the orthogonal experiment with trajectory parameters as the main influencing factor is designed. In Deform 3D process simulation system, the physical dynamic simulation of NC milling force is carried out, the influence rules of the trajectory parameters on the milling forces in X, Y and Z directions are analysed, and then the range analysis method is used to optimize the simulation data to get the optimal combination of the trajectory parameters. Taking the actual production of a small integral impeller as an example, the trajectory parameters before and after optimization are respectively applied to 5-axis NC machining and the data of product inspection show that the optimized trajectory parameters not only improve the rigidity of the blade root and reduce the overall deviation of the blade, but also verify that the small milling force is obtained after the optimization of the trajectory parameters for the finish machining aiming at the surface quality and the optimization scheme of the trajectory parameters proposed in this paper is feasible.
Gear Profile Measurement Based on Thin Line Structured Light
Authors: He Na , Wang Jianhua , Shang Zhiyi
Published: June 2023

In order to achieve the high precision 3D measurement of gear tooth profile, a telecentric optical measurement system with large FOV (field of view), WD (working distance) and measuring range was proposed, the system was applied to the gear tooth profile measurement experiment and obtained a good effect. Firstly, the composition and the principle of the system were introduced. The lights of projection and imaging with an angle of 45° from the normal line of the measured surface can reduce the requirement of DOF (depth of field) of the imaging objective lens. Secondly, in combine with the application background of small modulus gear tooth profile measurement, the magnification, NA (numerical aperture) and other optical parameters were calculated, the optical system was constructed and the system performance parameters are listed. Then, the calibration model of the system was demonstrated and the calibrations of depth pixel resolution and horizontal pixel resolution were completed through experiments. Finally, an involute artifact with a modulus of 2.9992mm and a total tooth profile deviation of 1.1μm was measured. The results show that the deviation of the total tooth profile measured is about 2μm, which is consistent with the calibration curve of the involute artifact.
Kinematic Modelling Analysis and Simulation of 6-DOF Manipulator
Authors: Zhao Jizhuo , Wan Hongqiang , Li Wei , Han Quanli
Published: June 2023

To test the rationality of the structure design of the six-degree-of-freedom manipulator, kinematics modelling and simulation were carried out. Firstly, the manipulator’s 3D model is created using SW platform. Secondly, the mathematical model of the manipulator is created according to the DH parameter method to complete the forward kinematics theoretical analysis. Finally, the reachable space of the end effector is simulated and an arc trajectory Simulation results indicate that the reachable space of the manipulator has no obvious cavity and the set trajectory curve is smooth without jumping points, the structure of the 6-DOF manipulator meets the design requirements.
Dynamic Simulation of Micro-flyer Shocked Detonation
Authors: Cheng Junxia , Tian Bo , Li Siyu , Li Xinyu , Wu Shenjiang
Published: June 2023

The shocked detonation technology of microflyer is safer and more stable via detonation. By using Ansys software to build a 3-D model of the flyer driven by explosive detonation, the mechanism of action, deformation and stress change were studied and analyzed. The shape and speed of the microflyer, when it strikes the main explosive, are controlled by the material, tilt-angle, and distance between the flyer and main explosive. The results showed that the microflyer needs 7.0 μs to reach 2490 m/s, which is its maximum speed. This study will provide a feasible method and reliable parameters for the safe and stable detonation of explosives.
Numerical Control Machining Process Parameters of Nickel-based Alloy Casing
Authors: Wang Zexiao , Zhang Xinyun , Wang Ning , Li Jintao , Wang Pengye
Published: June 2023

As a major component of engine, aviation casing is usually machined from superalloy blanks because it needs to withstand high temperature, high pressure and other environments during use. Surface integrity indexes such as surface roughness and residual stress will seriously restrict the performance and service life of such parts. In this paper, by studying the processing technology of the casing, Deform-3d software was applied to conduct three-dimensional dynamic modelling for the rough milling process of the casing made of nickel-based alloy GH4169, and the milling simulation analysis was carried out. With milling force and milling temperature as evaluation indexes, the variation rules of force and temperature under different coaxial and radial milling depths were obtained through simulation analysis. At the same time, the single factor optimization was carried out for different coaxial and radial milling depths according to evaluation indexes, and a set of optimal milling parameters were obtained, which provided theoretical guidance for practical machining.
Research on Deep Hole Machining Based on Aircraft Landing Gear
Authors: Cao Yan , Yang Qixin , Huang Liang , Tian Chunlei , Wang Panfeng , Wang Chenfei , Cai Keping
Published: June 2023

A landing gear is the main large bearing structural part of an aircraft. The change of material and structure makes the processing of the aircraft landing gear more difficult. Aiming at the structural characteristics of the aircraft landing gear deep cavity, the deep hole processing technique of a 300M steel workpiece was studied. A separated NC deep hole drilling and boring machine was adopted to process the workpiece. Cavity hole special cutting tools were introduced. Fixture and sealing mode were improved. NC programs were optimized. Thus, the processing problems of deflection, vibration, chip breaking and chip removal were solved. The workpiece with width to diameter ratio greater than 10 and surface roughness of hole is 3.2 μm was successfully machined by machining experiment, and the high efficiency machining of deep hole of ultra-high strength steel was realized. Thus the theoretical foundation is laid for the machining of complex cavity deep holes for cutting high-strength alloy materials.
Research and Implementation of Gear Measurement Based on Digital Twin Technology
Authors: Tang Yin , Wang Jianhua
Published: June 2023

The digital twin technology of the gear measurement center is a digital space mapping of the mechanical structure, workpiece performance and measurement process of the traditional gear measurement center, which is a gear measurement center designed according to the physical gear measurement center, but can independently complete the virtual measurement and function, which belongs to the digital software system. This paper studies the digital twin implementation steps of gear measurement center from the perspective of achievability, uses Opengl to develop graphics library, spatial geometry algorithm and digital integral interpolation algorithm, successfully establishes the digital twin gear measurement center model in VS2019, and conducts virtual measurement verification, obtains reliable data, verifies that the digital twin gear measurement center can complete the measurement process independently, solves the practical application problem of digital twin gear measurement center, and provides ideas for the development of virtual measurement.
Flexibility Analysis of One-dimensional Compliant Guiding Mechanism
Authors: Qiang Huaibo , Huang Qiang , Zhao Denghua
Published: June 2023

To realize the requirements of the precision probe for the translational guidance of compliant mechanism, the expression of the movement screw of the parallelogram guide mechanism is proposed. The flexibility matrix is used to study the influence of the geometric structure and size of flexible units on the performance of the guide mechanism, and the finite element analysis is used for simulation. The results show that the flexibility matrix model is in good agreement with the simulation results, and the maximum relative error is 6.33%. The motion screw method provides a new idea for the study of the motion characteristics of compliant mechanisms.
Research on Self-driving Vehicle Path Tracking Adaptive Method Based on Predictive Control
Authors: Gao Huihui , Song Xiaohua , Gao Song
Published: June 2023

The autonomous vehicles can improve the traffic utilisation and ensure the safe driving. Thus, the relative analysis is one hot research topic nowadays. The path tracking control system is one key link for the quick and stable tracking of target paths of autonomous vehicles. For analyzing the route tracing process of the Self-driving vehicles under complex working conditions, this paper proposes an adaptive model prediction controller. The controller chooses a vehicle dynamics model and incorporates a fuzzy adaptive control method into the model predictive control algorithm. Through the fuzzy adaptive control method, the weight of the objective function in the model predictive control algorithm is adaptively optimized to improve the control effects. The joint simulation tests are applied in the CarSim, MATLAB and Simulink software. Compared with the general model predictive controller, the outcomes indicate that the conceptualized controller can effectively reduce the tracking errors and ensure safe driving.
Study on Driving Characteristics of MEMS Electromagnetic Coil Using in the UAV
Authors: Xue Jingyun , Li Hanshan , Zeng Tao , Liu Xuebin , Zhang Yinhuan
Published: June 2023

The miniaturization and swarm design of unmanned aerial vehicle (UAV) is a research hotspot. For the current electromagnetic drive mode, the electromagnetic drive device is too large to be integrated in the current technology. This paper presents a new micro electromagnetically driven MEMS driving device, in which the electromagnetic coil is small in size, with a large electromagnetic force. We firstly designed and calculated the geometric structure of the electromagnetic coil, and analysed the model using COMSOL multiphysics field simulation software. We then carried out a parametric simulation of the electromagnetic coil. The simulation result shown that the error between theoretical calculation and the simulation of the mechanical and electrical properties of the electromagnetic coil was less than 2% under the same size. It provides an idea for UAV miniaturization design.
A Novel Method to the Aging Feature Extraction of Viscoelastic Sandwich Structures
Authors: Shi Xiaowei , Qu Jinxiu , Guo Jinzhu , Huang Jiaqi , Bai Yumei , Cao Wei
Published: June 2023

The viscoelastic sandwich structure exhibits highly nonlinear dynamic characteristics, and minimal changes in signal caused by aging state alterations, thus posing a challenge for extracting its aging characteristics. A method is proposed for extracting aging features from viscoelastic sandwich structures using variational mode decomposition (VMD) and permutation entropy (PE). First, the original dynamic response signal is decomposed by VMD to acquire several intrinsic mode functions (IMF). Then the permutation entropy characteristics of each IMF are calculated. The research results show that there are obvious differences in the distribution of permutation entropy corresponding to each IMF component, which indicates that the permutation entropy feature extracted based on the variational modal decomposition is more susceptive to the change of the aging state of the structure, thus verifying the availability of this method for feature extraction.
Individualized Analysis of the Stent Implantation Performance Based on the Vascular Reconstruction
Authors: Shao Feihu , Chen Hua , Liu Zheng
Published: June 2023

More and more researchers pay attention to the method of using stents treats the intracranial aneurysms through the way of minimally invasive surgery. Due to individual differences between patients and complexity of stenosis lesion, there is not an acknowledged criterion on stenting scheme, which mainly depends on clinicians’ experience. Otherwise, inappropriate stenting scheme may lead to severe complications such as intravascular restenosis after a certain period of time after surgery. By means of simulation to explore this problem is a simple and effective way, but most simulation studies only focus on the design of stent structure and ignore the importance of building a real blood vessel model. The use of idealized vascular model will inevitably affect the simulation accuracy, and it leads to a large difference between the theoretical effect and the actual effect of the stent. Therefore, reconstructing the accurate blood vessel model is the crucial work in this study. In order to research the mechanical properties of stents, the model is constructed by the OpenCASCADE kernel. It provides reference for assessing surgical plan and illuminating biomechanical mechanism of in-stent restenosis. At the same time, it may contribute to novel stent development and optimization design, assist doctor to make better surgical scheme as well as predict surgical results.
Two-frame Phase-shifting Interferometry by Minimizing the Residual-background
Authors: Shan Zeyuan , Du Hubing , Hu Bingqing , Feng Leijie
Published: June 2023

Demodulation of two random phase shift fringe patterns is an ill-posed problem. Existing methods often need to remove the fringe background by pre filtering in the frequency, which takes more time, and have a great influence on the phase reconstruction because of the frequency aliasing, these limits the application of two frame phase-shift interferometry in actual production. In this case, this paper based on the idea of Statistical Average, proposes a Statistical Average technology for phase extraction of two frame randomly phase-shifted interferograms from rough to precision without pre filtering. The proposed methods based on minimizing the residual background, firstly estimates the average background by calculating the average for all pixels, and then adding and subtracting the two frames with the background removed. The phase shift and phase are solved by using the properties of trigonometric functions. Then the amplitude is solved using the obtained phase and phase shift. Finally, the background is solved and the original light intensity is updated. Compared with existing methods, our method has the advantages such as rapid convergence and quick calculation by offering the right initial value. The accuracy of my proposed method is approximately double that of existing methods. Simulation and experimental results show that our method is a practical method of two frame phase shift interferences, both simple and reliable.