Search

Magnetic skyrmioniums—with a composite structure comprising two skyrmions with opposite topological charges, exhibit unique dynamic behaviors that are crucial for technological advancements and have application potential for high-density and nonvolatile memory. This study explores the impact of periodic perpendicular magnetic anisotropy (PMA) and damping gradients on skyrmioniums. Utilizing the object oriented micromagnetic framework for detailed simulations, the effective control and enhancement of the skyrmionium stability and mobility through the periodic modulation of PMA and damping gradients is demonstrated. The results demonstrate the dynamic behavior and stability control of skyrmioniums in periodic PMA/damping gradient nanowires. Moreover, the critical influence of the periodic gradient on the skyrmionium motion and stability is highlighted. The results present new avenues for developing advanced memory technologies, leveraging skyrmionium's unique nonlinear behaviors to improve the device performance and reliability. [ABSTRACT FROM AUTHOR]

Realization of planar tetracoordinate arrangements of nitrogen atoms is challenging because their preference for localized bonding (caused by its high electronegativity) makes them typically tricoordinate. This is especially true for the more electronegative oxygen atoms. Herein, we computationally designed two clusters NBe4H4− and OBe4H4; they contain a planar tetracoordinate nitrogen (ptN) and planar tetracoordinate oxygen (ptO) atom, respectively. Remarkably, the former is a dynamically stable global minimum, while the latter is not. The bonding analysis proves that planar tetracoordination in NBe4H4− favors over tricoordination because of the presence of multicenter delocalized bonds. In contrast, the planar tricoordination dominates due to its weak delocalized bonding ability of oxygen in the OBe4H4 cluster. Moreover, the 6σ/2π double aromaticity due to multicenter delocalized bonds allows the NBe4H4− cluster to obtain additional stability. This cluster is a promising synthetic due its dynamic and thermodynamic stability. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) based on metal–nitrogen–carbon (M–N–C) compounds have been identified as a potential substitute for Pt-based oxygen reduction reaction (ORR) catalysts due to their facile availability and low cost. M1M2–N–C based dual-atom catalysts (DACs) may be utilised to regulate the active site and optimise their ORR activity. Accordingly, M1M2–N6–C14 (M1 = Mn, Fe, Co; M2 = late transition metals) DACs were constructed within a graphene slab. M1M2–N–C is more stable than the corresponding M1–N–C and M2–N–C due to the affinity between M1 and M2. Furthermore, the ORR activity of FeM–N–C (M = late transition metals), MnM–N–C (Co, Ru, Rh, Os, Ir, and Re) and CoM–N–C (M = Cu, Zn, Pd, and Pt) is enhanced in comparison to that of Fe–N–C, due to the modified electronic properties. In comparison to other active ORR electrocatalysts, FeCu–N–C is positioned at a relatively high level on the volcano plot. To gain further insight into the dynamic stability of FeCu–N–C under working conditions (*OOH, 80 °C), an ab initio molecular dynamics simulation was employed. The accelerated structural evolution of the FeCu–N–C electrocatalyst resulted in the Cu atom being pulled out of the N–C substrate plane. Nevertheless, the resulting Fe(vacancy)–N–C and Fe(vacancy)–NH–C electrocatalysts have been observed to retain high ORR activity and stability. The findings of this study have significant implications for the design of DACs. [ABSTRACT FROM AUTHOR]

We provide a framework to study stability notions for two-sided dynamic matching markets in which matching is one-to-one and irreversible. The framework gives center stage to the set of matchings an agent anticipates would ensue should they remain unmatched, which we refer to as the agent's conjectures. A collection of conjectures, together with a pairwise stability and individual rationality requirement given the conjectures, defines a solution concept for the economy. We identify a sufficient condition — consistency — for a family of conjectures to lead to a nonempty solution (cf. Hafalir, 2008). As an application, we introduce two families of consistent conjectures and their corresponding solution concepts: continuation-value-respecting dynamic stability, and the extension to dynamic markets of the solution concept in Hafalir (2008), sophisticated dynamic stability. • Unified framework to study stability notions in dynamic matching markets. • Agents' conjectures specify what matchings may ensue conditional on waiting to match. • Key property of conjectures, consistency, guarantees existence of solutions. • Provide two new solution concepts with consistent conjectures. [ABSTRACT FROM AUTHOR]

Some of spiro[chromane-3',2''-thiopyran]-4'-ones were oxidized via m-chloroperbenzoic acid and/or hydrogen peroxide to afford the corresponding nine spiro[chromane-3',2''-thiopyran]-4'-one 1''-oxides and three spiro[chromane-3',2''-thiopyran]-4'-one 1'',1''-dioxides, which were confirmed by spectral data (IR, 1H NMR, 13C NMR, MS-ESI, and MS-EI). Whereas, the yield of oxidation using hydrogen peroxide is higher than that of oxidation using m-chloroperbenzoic acid. Moreover, Gram-negative bacteria (Escherichia coli ATCC 25922), and Gram-positive bacteria (Staphylococcus aureus ATCC 6538) were adopted to test the antimicrobial activity of 12 newly synthesized compounds (7a, 8a-c, 9a, 10a-c, 11a, 12a-c). The three sulfoxide derivatives 8b, 10b, and 10c showed antimicrobial activity. Also, antioxidant activity was evaluated for the newly synthesized compounds and shows that, all newly synthesized compounds (7a, 8a-c, 9a, 10a-c, 11a, 12a-c) have antioxidant activity. Molecular dynamic and system stability, Binding interaction mechanism based on binding free energy calculation, Identification of the critical residues responsible for ligands binding, Ligand–residue interaction network profiles, and In silico ADMET properties prediction were studied for the new compounds. The results of molecular dynamic studies were consistent with the in vitro antibacterial and antioxidant activity. [ABSTRACT FROM AUTHOR]

Planar hypercoordination has intrigued researchers for decades, yet hydrogen remained absent from this category until recently. Despite some advancements, further exploration of the emerging field of planar hypercoordinate hydrogen chemistry is still necessary. Herein, we report a D4h symmetric H©Li4Au4− cluster containing a planar tetracoordinate hydrogen (ptH) center. Both density functional theory (DFT) and ab initio calculations revealed that designed H©Li4Au4− is a real global minimum. Meanwhile, it also possesses excellent dynamic stability. This stability is dominated by electrostatic interactions, and reinforced by multicenter covalent bonds rather than any aromaticity. Interestingly, it is the first superhalogen anion in the ptH cluster and is expected to experimental synthesis and characterization. [ABSTRACT FROM AUTHOR]

ABSTRACT The virtual synchronous generator (VSG)–based photovoltaic system is affected by the external environment and sudden changes in load, which can lead to deteriorations in dynamic characteristics of power and frequency and even system instability. To ensure the dynamic performance and stability of the system, it is necessary to adjust the inertia‐damping parameters in time. This paper proposes a new cooperative adaptive control strategy for VSG inertia and damping parameters by analyzing the output angular frequency change and angular frequency deviation during the dynamic process of the system. Segmental adaptation is based on the size of the perturbation. The parameter selection rule is improved to increase the sensitivity of the parameter adjustment, and the improved sign function is used to prevent the parameter overmodulation problem. Finally, the proposed strategy is verified to effectively improve the system response speed and antidisturbance ability by comparing it with the traditional strategy on the MATLAB/Simulink simulation platform. [ABSTRACT FROM AUTHOR]

This paper employs first-principles calculations to comprehensively investigate the structural, dynamic, electronic, mechanical, and optical properties of A 2 BH 6 (A = K, Rb; B Ge, Sn) perovskite hydrides. Mechanical, thermodynamic, and dynamic stabilities are confirmed through calculations of elastic constants, formation energies, and phonon dispersion. The B/G ratio, below 1.75, indicates a brittle nature and a preference for covalent bonding. Electronic property analysis reveals that these hydrides are indirect band gap semiconductors with band gap values of 1.897 eV, 2.468 eV, 2.129 eV, and 2.657 eV, respectively. Optical property studies demonstrate high ultraviolet absorption. A key focus of this study is the gravimetric hydrogen storage capacities, which are found to be 3.84 wt% for K 2 GeH 6 , 2.97 wt% for K 2 SnH 6 , 2.48 wt% for Rb 2 GeH 6 , and 2.09 wt% for Rb 2 SnH 6. These findings not only enrich the research on the physical properties of perovskite hydrides but also provide an important theoretical basis and new options for the development of efficient hydrogen storage materials. The crystal structure, hydrogen storage capacity and band gap value of A 2 BH 6 (A = K, Rb; B Ge, Sn). [Display omitted] • A 2 BH 6 (A = K,Rb; B Ge,Sn) perovskite has been investigated using first-principles. • A 2 BH 6 (A = K, Rb; B Ge, Sn) exhibits thermodynamic, mechanical and dynamical stability. • A 2 BH 6 (A = K, Rb; B Ge, Sn) is a medium width indirect band gap semiconductor. • A 2 BH 6 (A = K, Rb; B Ge, Sn) has a hydrogen storage capacity of 2.09 W% to 3.84 W%. • The desorption temperature is found to be 221.1 K for K 2 SnH 6. [ABSTRACT FROM AUTHOR]

Magnetically coupled resonant wireless power transfer (MCR‐WPT) system with constant power load (CPL), finds extensive applications in military, industrial, and medical treatment. However, this system can easily exhibit complex non‐linear behaviors under certain parameter conditions due to the influences of constant power loads, switching devices, and feedback controllers. These behaviors limit the effectiveness of controllers and reduce the efficiency and stability of the system. It is necessary to study the non‐linear characteristics of the MCR‐WPT system with CPL. The stroboscopic discrete mapping of the MCR‐WPT system with CPL is established. Then the system's non‐linear dynamics are analyzed theoretically using a bifurcation diagram, the maximal Floquet multipliers, and the maximal Lyapunov exponent spectrum obtained from the proposed discrete mapping. The results show that the MCR‐WPT system with CPL will exhibit rich non‐linear dynamics with the variation of the power of CPL, such as cyclic fold bifurcation, Neimark–Scaker bifurcation, border collision bifurcations, chaos, etc. The excellent alignment of experimental and theoretical outcomes in corresponding states confirms the accuracy of the proposed discrete mapping and the nonlinear analysis of the system. The results of this study can provide a reference for selecting parameters for an actual MCR‐WPT system with CPL. [ABSTRACT FROM AUTHOR]

Leveraging abundant and low-cost photocatalysts for efficient photocatalytic water splitting holds significant potential for sustainable energy solutions. In this study, we propose two-dimensional Janus structures, particularly GeSnX 2 , along with its quaternary derivatives Janus-XGe-SnY (where X, Y = P, As and X ≠ Y) as promising candidates for the overall water splitting based on first-principles calculations. First, it was confirmed that the studied phases possess thermodynamic, mechanical, dynamic and thermal stability. The analysis of electronic properties with the hybrid functional HSE06 showed that all examined materials are semiconductors. The absorption coefficients of these Janus monolayers show a strong capability for harvesting visible light due to their optimal bandgaps. Furthermore, a detailed evaluation of photocatalytic efficiency was conducted, highlighting the benefits of neutral conditions for manufacturing processes. Our calculations show that the band edge energy levels of GeSnP 2 , GeSnAs 2 , and AsGe-SnP effectively match the redox potentials required for both the hydrogen evolution (HER) and oxygen evolution (OER) processes. Furthermore, these materials demonstrated exceptional solar-to-hydrogen (STH) efficiency, exceeding the theoretical limits of conventional photocatalysts for water splitting (18%). Moreover, the bandgap, edge alignment, and photocatalytic efficiency of these monolayers can be fine-tuned by applying biaxial strain. In particular, the AsGe-SnP monolayer transitioned to a direct bandgap under a tensile strain of 2% and achieved an improved STH efficiency of 25.04%, highlighting its great potential for multifunctional optoelectronic applications and photocatalysis. [Display omitted] • GeSnX 2 and XGe-SnY (X, Y = P, As, X ≠ Y) 2D Janus were studied as photocatalysts. • GeSnP 2 , GeSnAs 2 , and AsGe-SnP are promising photocatalysts with high absorption. • GeSnAs 2 stands out for superior STH efficiency compared to other 2D Janus materials. • The bandgap, band edge positions and STH efficiency can be tuned by applying biaxial strain. [ABSTRACT FROM AUTHOR]

As inverter‐based resources like wind turbines increase, grid inertia and stability decrease. Optimal placement and control of energy storage systems can stablise low‐inertia grids. This paper investigates how optimal battery energy storage systems (BESS) enhance stability in low‐inertia grids after sudden generation loss. The sitting, sizing and control of BESS are determined simultaneously in each genetic algorithm (GA) population, then voltage and frequency stability is evaluated based on the network simulation. This continues until the optimal solution is found. A network based on Kundur's four‐machine system is modelled for the first study and two of the four synchronous generators (SGs) have been replaced with wind farms. Then, the production of the third SG has been decreased by 13%. According to the results, addition of wind farms causes the frequency drop below 49.6 Hz for more than 5 min, indicating instability. It is also demonstrated that with optimal control parameters and placement, a 60 MW BESS can alleviate the voltage and frequency fluctuations, leading to enhanced stability. This method has also been tested on the IEEE 39‐bus network, where the installation of a BESS with a capacity of 9 MVA could restore the frequency stability. [ABSTRACT FROM AUTHOR]

In the present work, we report on theoretical studies of thermodynamic properties, structural and dynamic stabilities, dependence of unit-cell parameters and elastic constants upon hydrostatic pressure, charge carrier effective masses, electronic and optical properties, contributions of interband transitions in the Brillouin zone of the novel Tl2HgGeSe4 crystal. The theoretical calculations within the framework of the density-functional perturbation theory (DFPT) are carried out employing different approaches to gain the best correspondence to the experimental data. The present theoretical data indicate the dynamical stability of the title crystal and they reveal that, under hydrostatic pressure, it is much more compressible along the a-axis than along the c-axis. Strikingly, the charge effective mass values ( m e ∗ and m h ∗ ) vary considerably when the high symmetry direction changes indicating a relative anisotropy of the charge-carrier's mobility. Furthermore, the Young modulus and compressibility are characterized by the maximum and minimum values ( E max and E min ) and ( β max and β min ) that are equal to (62.032 and 28.812) GPa and (13.672 and 6.7175) TPa–1, respectively. Additionally, we have performed calculations of the Raman spectra (RS) and reached a good correspondence with the experimental RS spectra of the Tl2HgGeSe4 crystal. The XPES associated to RS constitutes powerful techniques to explore the oxidized states of Se and Ge in Tl2HgGeSe4 system. [ABSTRACT FROM AUTHOR]

Improving the performance of nutation blood pumps has long been a focus of medical research. In this study, we introduce the finite element method combined with sensor-based experimental measurements to explore the factors affecting the stability of the levitated magnetic rotor in the blood pump. Initially, we derived Euler angle and motion state equations to describe the motion of the magnetically levitated rotor inside the blood pump. Subsequently, employing the finite element method, we analyzed various factors impacting the dynamic levitation stability of the rotor. Our results indicate that the size of the permanent magnet in the rotor bearing, the nutation angle, and the levitation gap are critical factors affecting the rotor's levitation stability. We discuss these crucial parameters in detail, highlighting their correlation with the levitation stability of the rotor. Furthermore, comparing our theoretically obtained magnetic forces with experimental results, we found the maximum difference to be within 8%. Overall, this study provides valuable insights to enhance the functionality of blood pumps and understand the key parameters affecting their design. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the drug-like properties of target molecules containing thiophene sulfonamide groups (7a–7s) using computational molecular docking techniques. The binding interactions of these derivatives were assessed using protein 2NSD (Enoyl acyl carrier protein reductase InhA, complexed with N-(4-methylbenzoyl)-4-benzylpiperidine, PDB DOI: 10.2210/pdb2NSD/pdb) as the receptor. Molecular docking results revealed notable docking scores for all compounds, ranging from −6 to −12 kcal/mol. Compounds 7e, 7i, and 7f, in particular, demonstrated impressive glide scores (>11 kcal/mol) and were selected for further analysis through molecular dynamics simulations, which provided deeper insights into their dynamic behavior and stability. The drug-like properties of these molecules were evaluated based on Lipinski’s Rule of Five and ADME (Absorption, Distribution, Metabolism, and Excretion) criteria and compared with known drugs. Additionally, we synthesized these target molecules (7a–7s) using Suzuki-Miyaura coupling with a nickel catalyst replacing palladium. The chemical structures of the synthesized compounds were confirmed through elemental analysis, LC-MS,1H-NMR, and 13C-NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Highlights Chelated titanate (CT) modified single‐layer graphene (CTMSG), exhibiting much better static and dynamic stability due to the synergy of physical and chemical bonds, was mixed with butadiene‐vinylpyridine latex (BL) to prepare composite (CTMSG‐BL) film to enhance its thermal conductivity. Furthermore, CTMSG‐BL was complexed with polyethylene terephthalate (PET) fabric to promote the thermal conductivity of the composite (CTMSG‐BL/PET). Compared with the samples without CTMSG, the thermal conductivity of CTMSG‐BL (CTMSG content: 0.2 wt%) and CTMSG‐BL/PET increased from 3.52 to 4.35 W/(m·K) and from 1.91 to 2.56 W/(m·K), improved by 19.1% and 34.0%. This benefits from the excellent orientation alignment of single‐layer graphene (SG) in BL film and the highly efficient construction of the thermal conductivity pathway. The CTMSG‐BL emulsion is suitable for preparing heat‐resistant thermal conductive film with a thickness of micro‐nano meter (~0.6 μm) by impregnation process because of the low viscosity of the CTMSG‐BL emulsion (3.61 mPa·s) and the good heat resistance of the pyridine groups of BL with average pyrolysis temperature about 444 °C. The CTMSG‐BL film and CTMSG‐BL/PET composites have excellent heat conduction and dissipation properties, exhibiting broad application prospects in thermal interface materials, aerospace, and transport. The static and dynamic stability of the CTMSG was significantly improved. Low viscosity CTMSG‐BL is suitable for preparing thermally conductive films. With the addition of CTMSG, the thermal conductivity of BL improved by 19.0%. With addition of CTMSG, the thermal conductivity of BL/PET improved by 34%. [ABSTRACT FROM AUTHOR]

ABSTRACT Neurons are exceptionally sensitive to oxidative stress, which is the basis for many neurodegenerative disease pathophysiologies. The posttranscriptional basis for neuronal differentiation and behavior is not well characterized. The steady‐state levels of mRNA are outcomes of an interplay between RNA transcription and decay. However, the correlation between mRNA transcription, translation, and stability remains elusive. We utilized a SH‐SY5Y‐based neural differentiation model that is widely used to study neurodegenerative diseases. After neuronal differentiation, we observed enhanced sensitivity of mature neurons to mitochondrial stresses and ferroptosis induction. We employed a newly developed simplified mRNA stability profiling technique to explore the role of mRNA stability in SH‐SY5Y neuronal differentiation model. Transcriptome‐wide mRNA stability analysis revealed neural‐specific RNA stability kinetics. Our analysis revealed that mRNA stability could either exert the buffering effect on gene products or change in the same direction as transcription. Importantly, we observed that changes in mRNA stability corrected over or under transcription of mRNAs to maintain mRNA translation dynamics. Furthermore, we conducted integrative analysis of our mRNA stability data set, and a published CRISPR‐i screen focused on neuronal oxidative stress responses. Our analysis unveiled novel neuronal stress response genes that were not evident at the transcriptional or translational levels. SEPHS2 emerged as an important neuronal stress regulator based on this integrative analysis. Motif analysis unveiled SAMD4A as a major regulator of the dynamic changes in mRNA stability observed during differentiation. Knockdown of SAMD4A impaired neuronal differentiation and influenced the response to oxidative stress. Mechanistically, SAMD4A was found to alter the stability of several mRNAs. The novel insights into the interplay between mRNA stability and cellular behaviors provide a foundation for understanding neurodevelopmental processes and neurodegenerative disorders and highlight dynamic mRNA stability as an important layer of gene expression. [ABSTRACT FROM AUTHOR]

ApxII is a vaccine antigen used to protect against porcine contagious pleuropneumonia, which is a significant threat to the pig industry. Here, we aimed to improve the proteolytic degradation stability of ApxII during its secretion by establishing a complete screening process of stable variants through bioinformatics and site-directed mutagenesis. We employed a combination of semi-rational and rational design strategies to create 34 single-point variants of ApxII. Among them, R114E and T115D variants exhibited better stability without compromising antigen activity. Furthermore, we constructed a multi-site variant, R114E/T115D, which demonstrated the best stability, activity, and yield. Protein stability and molecular dynamic analysis indicated that the greater solubility and lower structural expansion coefficient might explain the increased stability of R114E/T115D. Additionally, site T115 was identified as a key point of truncated ApxII stability. The R114E/T115D variant, with its proven stability and intact antigenic activity, holds promising prospects for industrial-scale applications in the prevention of porcine contagious pleuropneumonia. • A screening process of ApxⅡ variants was established to improve the molecular stability of truncated ApxⅡ. • An ApxⅡ variant with higher molecular stability, protein yield and immunoprotective efficacy was obtained by rational design. • Insight into the source of the enhanced proteolytic degradation stability was gained by molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

Nematode infections impose a significant health and economic burden, particularly as parasites develop resistance to existing treatments and evade host defenses. This study explores the efficacy of 48 paraherquamide analogs, a class of polycyclic spiro-oxindole alkaloids with unique structural features, as potential anthelmintic agents. Employing advanced computational methods, including molecular docking, MM-GBSA, and molecular dynamics simulations, we assessed the interaction of these analogs with the Ls-AchBP receptor, a model for nematode neurotransmission. Among the analogs studied, Paraherquamide K, Mangrovamide A, and Chrysogenamide A showed comparable docking and MM-GBSA scores to the native antagonist. Notably, their binding interactions exhibited slight distinction attributed to structural differences, such as the absence of a di-oxygenated 7-membered ring. Additionally, these analogs demonstrated robust binding stability in the molecular dynamic simulation studies and favorable pharmacokinetic properties in our in-silico ADME assessment. The insights gained from the study highlight the potential of these analogs as a basis for developing new therapeutics for nematode infections. The promising results from this computational analysis set the stage for subsequent in-vivo validations and pre-clinical studies, contributing to the arsenal against parasitic resistance. [ABSTRACT FROM AUTHOR]

Two-dimensional materials have excellent electronic and optical properties, suggesting absolute advantages in nanodevices. In this work, a new two-dimensional material with a puckered structure, a C2B6 monolayer, is proposed. The material presents dynamic and thermal stability calculated by first-principle simulations. Interestingly, the C2B6 monolayer possesses semiconductor behavior with an ultra-narrow bandgap of approximately 0.671 eV by HSE06 functional. Meanwhile, the hole in the C2B6 monolayer shows ultrahigh mobility at approximately 6,342 cm2⋅V−1⋅s−1 in decent transport directions, which is larger than traditional transition metal dichalcogenides materials. More importantly, the pronounced anisotropy of mobility of the electrons and holes can separate the photogenerated charges, suggesting the applications for photocatalytic, photovoltaic and optical and cold chain electronic devices. Then, the novel properties of the light absorption characteristic are obtained, and the anisotropic photocurrent implies the C2B6 monolayer can be used as a potential photoelectric device. Our results provide theoretical guidance for the design and application of two-dimensional materials. [ABSTRACT FROM AUTHOR]

Allotropy structures may induce different electronic and optical properties, which implies that one can acquire novel performance by screening its allotropy structures. Here, we demonstrate that two In 2 S 3 allotropy monolayers with excellent photocatalytic performance for water splitting to produce hydrogen are screened from 1038 In 2 S 3 allotropy monolayers. The phonon dispersions are calculated for 39 allotropes with the lowest formation energies, which confirms that 16 allotropes have dynamic stability, including the only one reported in the literature. The results of overpotentials of band edges demonstrate that 8 allotropes match the potential requirements of overall water splitting. The thermodynamic stability of these allotropes is further confirmed for the obtained allotropes. Then, two allotropes with maximum solar-to-hydrogen efficiency of 17.78% and 29.32% are screened. The Gibbs free energy with the solvent effect indicates that one allotrope can proceed photocatalytic hydrogen/oxygen evolution reactions spontaneously. Therefore, the newfound In 2 S 3 allotropy monolayers have potential applications in photocatalytic overall water splitting for hydrogen generation. [Display omitted] • 8 In 2 S 3 monolayers for photocatalytic HER/OER are screened from 1038 allotropes. • The maximum η STH ′ of 29.32% is attributed to the In 2 S 3 -VIII monolayer. • Photocatalytic HER/OER can spontaneously proceed with In 2 S 3 -VI/VIII monolayers. • η STH ′ of In 2 S 3 -VI monolayer can be boosted from 17.78% to 30.16% by adjusting pH. [ABSTRACT FROM AUTHOR]

Ground roughness can significantly impact the battery performance in greenhouse environments. In this study, battery energy management was integrated with path planning to address this challenge. A systematic investigation was also implemented to explore the effects of ground roughness on the battery life and utilization efficiency of greenhouse vehicle platforms. A graded pre-scoring model was constructed using prior knowledge. Additionally, the Manhattan distance between the vehicle's current position and the target point was incorporated into the reinforcement learning reward function, thus linking travel distance with battery life to optimize both battery utilization efficiency and life during path planning. An Adaptive Multi- step Q-learning algorithm (AMQL) with adaptive step sizes and an Adaptive ε-greedy Q-learning algorithm (AEQL) with an adaptive exploration rate was proposed to enhance the performance of the Q-learning algorithm. The traditional Q-learning algorithms were associated with some issues, such as long iteration times, low convergence efficiency, susceptibility to local optima, and excessive path turns. The AMQL algorithm was used to adjust the step size, according to the forward reward assessment, if the reward at the current position increased corresponding to the previous reward, the step size increased. The step size gradually decreased to prevent suboptimal path optimization, as the current position approached the endpoint. The AEQL algorithm was used to adaptively adjust the exploration rate ε using the difference between adjacent reward values—ε increased when the adjacent reward value increased, and ε decreased when the reward value decreased. Although AMQL improved the convergence efficiency and iteration speed, the variations in the step size caused significant fluctuations in rewards, resulting in lower algorithm stability. Additionally, there was no outstanding impact of multi-step length on the convergence efficiency and iteration speed. Furthermore, the AEQL enhanced the exploration efficiency and algorithm stability through dynamic adjustments. But its fluctuating rise during the initial training phase also increased the training time. Therefore, the AMQL and AEQL algorithms were combined to develop an Adaptive Multi-step and ε-greedy Q-learning algorithm (AMEQL), in order to ensure faster and more optimal global path selection during path planning. In a simulated environment, the models were first used to simulate a realistic greenhouse tomato scenario. Then, an Inertial Measurement Unit (IMU) was used to record the changes in the aisle roughness in real time. This data was then incorporated into the simulation model. Finally, 300 rounds of simulation experiments were carried out to test the traditional Q-learning, AMQL, and AMEQL algorithm for path planning in the single-row (30 m×20 m), double-row (50 m×50 m), and triple-row (70 m×50 m) environments. Simulation results show that the AMEQL algorithm reduced the average training time by 44.10%, the average number of iterations required for convergence by 11.06%, the number of path turns by 63.13%, and the post-convergence average fluctuation by 15.62%, compared with the traditional Q-learning. Due to its higher convergence speed in 400 iterations, the AMEQL algorithm averaged 14 fluctuations per 100 iterations after reaching the maximum reward, while the AMQL algorithm averaged 15 fluctuations. This algorithm can provide a theoretical reference for the autonomous path planning of greenhouse platforms. [ABSTRACT FROM AUTHOR]

Purpose: This research aims to investigate the trajectory tracking problem for a four-wheel independent drive autonomous vehicle (4WID) and propose an integrated, coordinated control strategy to address the mutual interference between trajectory tracking and stability control in extreme cases. Design/methodology/approach: The authors establish an adaptive preview model that modifies the preview distance based on vehicle speed. They utilize a three-degrees-of-freedom vehicle model and employ model predictive control to calculate the necessary front wheel angle for trajectory tracking. In terms of longitudinal control, a longitudinal coordinated control mechanism is established to achieve the two conflicting objectives of trajectory tracking accuracy and dynamic stability through early deceleration. A stability controller based on sliding mode control (SMC) is designed, considering tire constraints and tracking the optimal yaw angle and sideslip angle. Furthermore, a lateral coordinated control strategy is developed, considering the weight coefficient of stability control, and the yaw moment is calculated and distributed based on the vehicle torque requirements. Findings: The proposed integrated, coordinated control strategy successfully addresses the mutual interference between trajectory tracking and stability control in extreme cases for the 4WID vehicle. The strategy achieves trajectory tracking accuracy, dynamic stability and reduced energy consumption while taking into account tire constraints. Originality/value: We have proposed a cooperative control strategy for the trajectory tracking problem of autonomous driving vehicles. This strategy is different from previous methods in that we have taken into account the integrated dynamic control in both longitudinal and lateral directions, balancing the conflicting control requirements and reducing energy consumption, improving trajectory tracking accuracy and vehicle dynamic stability. We have verified the feasibility of this strategy through joint simulation under different driving conditions. [ABSTRACT FROM AUTHOR]

Taking the pipe segments of the Hongkong -Zhuhai -Macao Bridge immersed tube tunnel were regarded as theresearch object, a three-dimensional dynamic finite element model was established using MIDAS GTS NX software. Interfaceelements were used to simulate the joint of the pipe segments, and the dynamic response characteristics of the immersed pipesegments and high -pressure rotary jet grouting pile soft soil composite foundation were analyzed by applying heavy -dutyvehicle simulation vibration loads. The research results indicate that vehicle vibration loads can induce significantenvironmental vibration effects on the pipe segments and composite foundations of underwater immersed tube tunnels. Whenatrailer of 120 level passes through an underwater immersed tube tunnel at a speed of 80 km/h, the maximum verticaldisplacement generated at the joint of the immersed pipe segments can reach 3.21 mm, and the maximum peak acceleration canreach 17.77 mm/s²; The maximum displacement of the top surface of the high-pressure rotary jet pile composite foundation canreach 1.98 mm, and the peak acceleration can reach 2.38 mm/s². The acceleration vibration level at the joint of the immersedpipe segments can reach 81.9 dB. The influence of heavy -duty vehicle operation on the dynamic stability of submarineimmersed tube tunnels on soft soil composite foundation cannot be ignored. [ABSTRACT FROM AUTHOR]

The recognition of the transient dominant instability mode is of great significance for rapidly and accurately formulating transient emergency decisions in power systems. In response to the challenge of accurately distinguishing between angle instability and voltage instability, which are coupled in actual power grids, this paper explores the mapping relationship between simulation data and the stable state of the system, as well as the dominant instability mode. The method enables real‐time identification of the dominant instability mode, which bypasses complex physical mechanisms. Firstly, spatio‐temporal feature mining is conducted, where convolutional neural networks are employed to learn crucial local features of transient curves, and bidirectional gated recurrent unit s utilized to learn transient features over time sequences. Next, a multihead attention mechanism is introduced to enhance sensitivity to important time steps in the sequence data. Finally, the transit search optimization algorithm optimizes the global model parameters, further increasing the accuracy of the model. Using the IEEE 10‐machine and 39‐node system as an example for simulation, the results validate that the proposed method exhibits significant advantages in terms of accuracy and applicability compared with other machine learning methods. [ABSTRACT FROM AUTHOR]

This paper presents a prediction‐based algorithm designed to address out‐of‐step (OOS) conditions in power systems. The algorithm utilizes generator data obtained from phasor measurement units. The transient stability of a multi‐machine power system is evaluated using the equal‐area criterion (EAC). The proposed algorithm calculates the characteristics of the P‐δ curves within the EAC framework after a large disturbance. The critical P‐δ trace is determined by analysing the cumulative energy in the acceleration area following fault clearance. The stability margin of the rotor angle is then computed based on the actual active power and its relationship with the critical curve. The algorithm predicts the occurrence of OOS by comparing the measured active power with the corresponding value on the critical curve. Furthermore, a complementary strategy is proposed to predict the OOS condition in integrated inverter‐based power systems. The effectiveness of the proposed algorithm is validated through simulations conducted on the 73‐bus IEEE test power system. [ABSTRACT FROM AUTHOR]

Its outstanding mechanical and thermodynamic characteristics make SrAl2O4 a highly desirable ceramic material for high-temperature applications. However, the effects of elevated pressure on the structural and other properties of SrAl2O4 are still poorly understood. This study encompassed structural, elastic, electronic, dynamic, and thermal characteristics. Band structure calculations indicate that the direct band gap of SrAl2O4 is 4.54 eV. In addition, the Cauchy pressures provide evidence of the brittle characteristics of SrAl2O4. The mechanical and dynamic stability of SrAl2O4 is evident from the accurate determination of its elastic constants and phonon dispersion relations. In addition, a comprehensive analysis was conducted of the relationship between specific heat and entropy concerning temperature variations. [ABSTRACT FROM AUTHOR]

Preparation of high-performance thermosetting resins via bio-based resources is important for the development of a sustainable world. In this work, we proposed the introduction of cyanide structure groups into the molecular structure of epoxy resins to give them excellent heat resistance. A eugenol-based epoxy-phthalonitrile (EEPN) resin was synthesized by a two-step process using the bio-based renewable resource of eugenol, and a series of EEPN/Epoxide resin (E51) blend resins with different EEPN contents were prepared. The structure of the EEPN monomer was characterized and confirmed by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and elemental analysis. The thermal stability and dynamic mechanical properties of the cured resins were investigated by thermogravimetric analysis and dynamic mechanical thermal analysis. The experimental results showed that EEPN had excellent heat resistance; the char yield at 800 °C was 67.9 wt%, which was much higher than that of E51 at 26.3 wt%; and the heat resistance of the blended resins was significantly improved with the increase in the EEPN content. [ABSTRACT FROM AUTHOR]

This study proposes a wearable gait assessment method using inertial measurement units (IMUs) to evaluate gait ability in daily environments. By focusing on the estimation of the margin of stability (MoS), a key kinematic stability parameter, a method using a convolutional neural network, was developed to estimate the MoS from IMU acceleration time-series data. The relationship between MoS and other stability indices, such as the Lyapunov exponent and the multi-site time-series (MSTS) index, using data from five IMU sensors placed on various body parts was also examined. To simulate diverse gait conditions, treadmill speed was varied, and a knee–ankle–foot orthosis was used to restrict left knee extension, inducing gait asymmetry. The model achieved over 90% accuracy in classifying MoS in both forward and lateral directions using three-axis acceleration data from the IMUs. However, the correlation between MoS and the Lyapunov exponent or MSTS index was weak, suggesting that these indices may capture different aspects of gait stability. [ABSTRACT FROM AUTHOR]

In a multi-fed DC environment, the UHV DC recipient grid faces significant challenges related to DC phase shift failure and voltage instability due to the high AC/DC coupling strength and low system inertia level. While the new large-capacity synchronous condensers (SCs) can provide effective transient reactive power support, the associated investment and operation costs are high. Therefore, it is valuable to investigate the optimization of SC configuration at key nodes in the recipient grid in a scientific and rational manner. This study begins by qualitatively and quantitatively analyzing the dynamic characteristics of DC reactive power and induction motors under AC faults. The sub-transient and transient reactive power output model is established to describe the SC output characteristics, elucidating the coupling relationship between the SC's reactive power output and the DC reactive power demand at different time scales. Subsequently, a critical stabilized voltage index for dynamic loads is defined, and the SC's reactive power compensation target is quantitatively calculated across different time scales, revealing the impact of transient changes in DC reactive power on the transient voltage stability of the multi-fed DC environment with dynamic load integration. Finally, an optimal configuration model for the large-capacity SC is proposed under the critical stability constraint of dynamic loads to maximize the SC's reactive power support capability at the lowest economic cost. The proposed model is validated in a multi-fed DC area, demonstrating that the optimal configuration scheme effectively addresses issues related to DC phase shift failures and voltage instability resulting from AC bus voltage drops. [ABSTRACT FROM AUTHOR]

This paper presents an advanced workflow for processing radar imagery stacks using Persistent Scatterer and Distributed Scatterer Interferometry (PSDS) to enhance spatial coherence and improve displacement detection accuracy. The workflow leverages Level 2 Coregistered Single Look Complex (L2-CSLC) images generated by the open-source COMPASS (Coregistered Multi-temporal Sar SLC) framework in combination with the Combined eigenvalue maximum likelihood Phase Linking (CPL) approach implemented in MiaplPy. Starting the analysis directly from Level 2 products offers a significant advantage to end-users, as they simplify processing by being pre-geocoded and ready for immediate analysis. Additionally, the open-source nature of the workflow and the use of L2-CSLC products simplify the processing pipeline, making it easier to distribute directly to users for practical applications in monitoring infrastructure stability in dynamic environments. The ISCE3-MiaplPy workflow is compared against ISCE2-MiaplPy and the European Ground Motion Service (EGMS) to assess its performance in detecting infrastructure deformations in dynamic environments, such as the Algeciras port. The results indicate that ISCE3-MiaplPy delivers denser measurements, albeit with increased noise, compared to its counterparts. This higher resolution enables a more detailed understanding of infrastructure stability and surface dynamics, which is critical for environments with ongoing human activity or natural forces. [ABSTRACT FROM AUTHOR]

Effective postural control is essential for motor skill development, yet the specific nature of anticipatory control in children with Developmental Coordination Disorder (DCD) remains poorly understood for complex or dynamic stability tasks. This study investigated anticipatory postural adjustments (APA) during a self-initiated dynamic stability task. The Can Placement Task (CPT)—a self-initiated dynamic stability task—was performed by 23 children with DCD and 30 typically developing (TD) children aged 9–12 years. The task involved standing on one leg while also repositioning a can on the floor. Center of pressure (COP) movement was recorded by two force platforms during the five phases of the movement. The ground reaction force measured external support during both descent to pick up the can and ascent after replacing the can. The study used a mixed-design approach with group (DCD, TD) as a between-subject factor and condition (can position close or far) and phase of movement as within-subject. Distinct movement control characteristics were shown for children with DCD including a greater range of COP movement and higher COP velocity in the anterior-posterior direction prior to movement initiation compared with TD. The DCD group also relied more on external support during both the downward and upward phases of the CPT and needed more trials to complete the task. Only two significant interaction effects involving Group and the within-subject factors emerged. Children with DCD swayed significantly more at specific phases of the task, especially when coming up and restoring balance, and did not adapt COP velocity as a function of reaching distance. Dynamic control of posture in children with DCD is impaired as they struggle to generate the effective APAs necessary to maintain dynamic stability which leads to greater reliance on external support and more corrective movements. The CPT provides a valuable assessment of posture and dynamic balance control during a complex prehension movement performed on one leg; the task highlights distinct movement patterns between children with and without DCD. [ABSTRACT FROM AUTHOR]

In this paper, a nonclassical shell model is utilized to investigate the dynamic stability of functionally graded piezoelectric (FGP) nanoshells considering the thermo-electro-mechanical coupling effects. Also, the FGP nanoshells on elastic foundations are subjected to periodic axial loading. The theoretical formulations are derived by implementing the first-order shear deformation (FSD) shell theory into the nonlocal strain gradient theory (NSGT). Hamilton's principle is utilized to obtain the equations of motion and related boundary conditions of the present nanoshell model. Moreover, the Mathieu-Hill equations determining the instability regions are presented and analyzed based on Bolotin's method. Results demonstrate that the external electric voltage, the elastic foundations, the temperature rise, the static load factor, the power-law index and the small-scale parameters have significant influences on the dynamic stability responses of FGP nanoshells. [ABSTRACT FROM AUTHOR]

This article proposes an optimal approach of improving the dynamic stability in power system by using hybrid method based power system-stabiliser. The proposed hybrid approach is an integration of Owl Search algorithm (OSA) and Improved Grey Wolf Optimizer (IGWO); hence, it is known as OSA-IGWO method. The objective of the proposed method is to enhance the power system's dynamic stability. This notion offers a singular approach to design the sturdy Power System Stabiliser (PSS) and enhance the dynamic energy machine balance. The Modified Heffron-Phillip's version can be evolved through generator facet transformer voltage because endless bus voltage and connection are considered to lessen the complexity with computational time. An energy machine stabiliser is referred to as Modified Power System Stabiliser (MPSS) that can be evolved and incorporated with PID controller; the usage of proposed approach in a Single-Machine-Infinity Bus-System uses Modified Heffron-Phillips (MHP) version. The OSA-IGWO approach may be used to select the benefit sets of PID-MPSS. The proposed version complements the dynamic overall performance of machine via the way of means of growing the damping ratio of the energy machine below diverse running conditions. The OSA-IGWO method is done in MATLABplatform, and its performance is compared with existing methods. [ABSTRACT FROM AUTHOR]

A quantitative assessment of the seismic stability of anchored anti-dip slopes is of great importance for the safety of residents and infrastructure in seismically active regions. However, the subject has received relatively little scientific attention globally. This study aims to analyze the dynamic stability of an anchored anti-dip slope during the Ludian earthquake in Yunnan Province, China, a region characterized by active faults and frequent strong earthquakes. The Manhekuan slope located near the Lancang River fault, an active fault in Yunnan Province, was chosen as a case study to propose a method that integrates engineering geological investigations with the discrete element method (DEM). To validate its effectiveness, the proposed method is compared with the pseudo-static method and subsequently applied to optimize the anchorage parameters of the Manhekuan slope. The results indicate that the stability factor achieved by the proposed method is slightly higher than that of the pseudo-static method, showing a 3.6% increase. The proposed method effectively describes the shear evolution characteristics of the anchor cable and its influence on the seismic dynamic stability of the anchored anti-dip slope. The dynamic stability of the Manhekuan slope under the Ludian earthquake is reasonably analyzed using three indices: stability factor, geological body displacement, and anchorage force. This analysis leads to the determination of optimal anchorage parameters for the Manhekuan slope. The findings provide a valuable reference for evaluating the seismic stability of anchored slope engineering in seismically active regions, including the Himalayas. [ABSTRACT FROM AUTHOR]

Aging degradation of the geomembrane (GMB) significantly influences the dynamic shear characteristics of the composite liner interface, which comprises the GMB and the compacted clay liner (CCL), potentially jeopardizing the dynamic stability of landfills. In this study, cyclic shear tests were performed on two types of aging GMB/CCL interfaces, concurrently with shear tests on the nonaging GMB/CCL interface for comparison. The results suggest that the impact of aging on the dynamic shear characteristics of the GMB/CCL interface is essentially governed by the surface roughness and brittleness of the GMB, with the effect degree of brittleness influenced by the normal stress. Under low normal stress, aging increased the vertical displacement, dynamic shear strength, and shear stiffness of the GMB/CCL interface. However, under high normal stress, the dynamic shear strength and shear stiffness of the aging GMB/CCL interface were more likely to be lower than those of the nonaging interface. As the displacement amplitude increased, the influence of aging on the shear stiffness of the GMB/CCL interface gradually diminished. Aging also reduced the damping ratio of the GMB/CCL interface. The difference in vertical displacement between the exposed GMB/CCL interface and the in soil GMB/CCL interface caused by brittleness was not significant. In practical engineering, when the overlying load on the GMB/CCL composite liner is relatively small, aging makes the GMB more susceptible to tearing under seismic loads, whereas with larger overlying loads, aging is more likely to increase the shear displacement, thereby increasing the likelihood of instability in landfill. Finally, based on classic models of soil, fitting models for the normalized shear stiffness and damping ratio of the GMB/CCL interface were established and validated. This study can provide reference for analyzing the dynamic stability of landfills during long-term use. [ABSTRACT FROM AUTHOR]

This paper proposes a saturation-optimized, quasi-sliding-mode model-free adaptive control (SM-MFAC) method to control the postcollision calming motion of an unstable free-flying space robot with saturated output torque. Initially, the dynamics model of the unstable free-flying space robot is transformed into a class of multiple-input, multiple-output (MIMO) discrete-time nonlinear systems. Here, the system characteristics can be estimated based on measured base attitude and joint angle data. The discrete sliding-mode control helps calculate the desired angular velocity at the current moment. Next, Hildreth's method is used to introduce constraints to the control input criterion function for real-time tracking of the desired angular velocity, which enables the completion of the calming motion control of the free-flying space robot. The proposed algorithm simplifies the traditional calming motion control process by avoiding complex and redundant modeling requirements, ensuring that the control torque remains within predefined limits to optimize possible saturation. It also proves the convergence of the system output theoretically, and good stability and dynamic characteristics of the control scheme are verified through numerical simulations. [ABSTRACT FROM AUTHOR]

Vibration is inevitable in operation of mechanical equipment, but severe vibrations will cause serious harm to wind turbines (WTs). This paper takes the drivetrain of 8 MW WT as the object, established a multi-body electromechanical coupling model of WT and verified the accuracy of the established model through the WT drivetrain in the laboratory. Subsequently, based on this model, time-frequency domain analysis was conducted on the vibration response of the WT drivetrain under different control strategies of the generator, and the influence of the generator control strategy on the vibration of the drivetrain was studied. The result shows that the generator control strategy has a significant impact on the vibration response amplitude of the drivetrain, but has a relatively small impact on the frequency component. Meanwhile, the sliding mode controller designed in this paper has good anti-interference ability, which can make the system quickly reach dynamic stability, and effectively suppress the vibration of the main components in the drivetrain. Under the new controller's control, the transverse vibration displacement of some parts of the WT drivetrain can be reduced by up to nearly 60 %. This paper provides new ideas and new methods for the active vibration reduction control of WT drivetrain. [ABSTRACT FROM AUTHOR]

Copyright of Uranium Mining & Metallurgy is the property of Uranium Mining & Metallurgy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents a comparative study on the stability and dynamic response of hybrid laminated composite plates over monolithically produced laminated composite plates. A Refined Higher-order Zigzag Theory (RHZT) is formulated and implemented using finite element method for the analysis of hybrid laminates. This formulation considers both the interlaminar shear stress continuity and shear-free boundary conditions at surfaces of the plates. The numerical implementation employs C0 continuous eight-noded isoparametric plate elements considering geometric nonlinearity. The element stiffness matrix is formulated to consider both the linear and nonlinear terms of the strain-displacement equations. Derivation of the consistent mass matrix for a plate element is presented following the approximation of total kinetic energy and utilising Hamilton's principle. Numerical examples are provided to demonstrate buckling and free vibration analyses (as eigenvalue problems). The results are numerically verified and validated using data from published literature. Finally, parametric studies are presented to demonstrate the effectiveness of fibre hybridisation approach on the buckling and free vibration behaviour of laminated composites. [ABSTRACT FROM AUTHOR]

The highest ambient‐pressure Tc among binary compounds is 40 K (MgB2). Higher Tc is achieved in high‐pressure hydrides or multielement cuprates. Alternatively, are explored superconducting properties of binary, metastable sub‐oxides, that may emerge under extremely low oxygen partial pressure. The emphasis is on the rock‐salt structure, which is known to promote superconductivity, and exploring AlO, ScO, TiO, and NbO. Dynamic lattice stability is achieved by introducing metal and oxygen vacancies in the fashion of Nb1−xO1−x‐type structure (x = ¼). The electron‐phonon (e‐ph) coupling is remarkably large in Al1−xO1−x and Ti1−xO1−x (λ ≈ 2 at x = ¼), with Tc ≈ 35 K according to the Allen–Dynes equation. Significantly, the coupling strength is comparable to that in high‐pressure hydrides, yet, in contrast to hydrides and MgB2, the coupling is largely driven by low frequency phonons. Sc1−xO1−x and Nb1−xO1−x show significantly smaller λ and Tc. Further, hydrogen intercalation to boost λ and Tc is investigated. Only Ti1−x(O1−xHx) and Nb1−x(O1−xHx) are dynamically stable upon intercalation, where H, respectively, decreases and increases Tc. The effect of H doping on electronic structure and Tc is discussed. Altogether, the study suggests that metal sub‐oxides are promising compounds to achieve strong e‐ph coupling at ambient pressure. [ABSTRACT FROM AUTHOR]

Based on the principles of reinjection converter technology and submodule operation, a novel topology for a reinjection multilevel voltage source converter (RMVSC) is proposed. In this topology, submodules are dynamically connected in series as the reinjection circuit. This new topology retains all the functions of the RMVSC while offering flexible control of the reinjection circuit and ease of modularization, making it highly suitable for high-voltage, high-power applications. A circulating drive pulse sequence was developed for the 7-level serial submodule RMVSC, ensuring dynamic stability of the submodule voltage and maintaining low harmonic distortion when interfaced with the grid. Building on this, a double-loop control strategy—comprising an outer power loop and an inner current loop—was proposed for the static synchronous compensator (STATCOM) of RMVSC. A simulation model was constructed in PSCAD/EMTDC, and the simulation results confirm the excellent performance of the proposed topology and the effectiveness of both the modulation strategy and the double-loop control strategy. The RMVSC-STATCOM demonstrates continuous and bidirectional reactive power regulation, with high control accuracy and superior compensation current quality. [ABSTRACT FROM AUTHOR]

To investigate the influence of gear floating on the load sharing characteristics of the Coaxial Reverse Closed Differential Herringbone Gear Transmission System (CRCDHGTS) and the rotational speed difference between the upper and lower rotors, a dynamic Bending-Torsional-Axial-Pendular (BTAP) model of the CRCDHGTS was established using the centralized parameter method, which considers various excitation factors such as gear floating, errors, Time Varying Meshing Stiffness (TVMS), gyroscopic effect, and tooth friction. It considers the interaction between the closed-stage gear set and the differential-stage gear set, treating the herringbone gear as a symmetric helical gear connected through a receding slot. The dynamic model was solved using the Runge-Kutta method to obtain the dynamic meshing forces for each gear pair under single and combined floating modes. The Dynamic Load Sharing Coefficient (DLSC) of the system, which characterizes the Load Sharing Performance (LSP), was deduced. The load sharing characteristics of different floating modes were analyzed, as well as the influence of different floating displacement on the DLSC. The motion path of the gear floating was also determined. Additionally, the impact of manufacturing error and assembly error of each component on the DLSC under combined floating mode was analyzed. Finally, the influence of gear floating on the output rotation speeds of the upper and lower rotors of the system was investigated. The results indicate that both free-floating of the center gear and combined floating can effectively improve the LSP of the system. When the system adopts combined floating mode, the DLSC of inner and outer meshing changes between 0.91 and 1.09, demonstrating a significant improvement in the LSP. The DLSC of the system increases with the increase in error, with the eccentricity error having a greater impact on the DLSC compared to the assembly error. The optimal floating value for the sun gear is between 0.6 mm and 0.8 mm, while for the planetary gear, it is between 0.4 mm and 0.6 mm. The rotational speed difference between the upper and lower rotors can be controlled within 1r/min. These research findings provide a theoretical basis for further analysis of the dynamic stability and reliability of the system. [ABSTRACT FROM AUTHOR]

We study a class of asymmetric games with compact Polish strategy sets and provide sufficient conditions for the stability and convergence of profiles under the infinite-dimensional replicator dynamics on such games. We apply these results to analyze the dynamic behavior of the Cournot duopoly with different pricing mechanisms, the rope-pulling game, and a game with a Nash equilibrium profile consisting of uniform distributions. Further, we prove that the set of all Gaussian profiles remains invariant under the replicator dynamics on a large class of quadratic games. Moreover, we study the dynamics restricted to the set of Gaussian profiles, both analytically and numerically. [ABSTRACT FROM AUTHOR]

The propensity for roll instability in automobiles, particularly trucks, often arises during high‐speed maneuvers and emergency scenarios. The active roll control (ARC) system presents a promising solution for enhancing truck roll stability. This study delves into designing a controller for the ARC system adapted to high‐speed truck operations. It entails formulating a cost function for the linear quadratic regulator (LQR) optimal controller, incorporating variables directly pertinent to truck roll stability: vehicle body's roll angle, unsprung masses' roll angle, and normalized load transfer at the two axles. To streamline sensor usage and prioritize cost‐effectiveness, the Luenberger observer is integrated with the full‐state feedback LQR controller. The investigation involves executing double lane change maneuvers, simulating overtaking and obstacle avoidance, at speeds of 70, 100, 130, and 160 km/h. The maximum absolute value of the normalized load transfer coefficient at the axles is assessed up to speeds of 200 km/h. Research findings underscore the efficacy of the ARC system in enhancing truck safety by reducing the normalized load transfer of all axles over 30% compared to the passive system, particularly during high‐speed operations. [ABSTRACT FROM AUTHOR]

In this work, we use first-principles to calculate the structural, mechanical, electronic, dynamic, thermodynamic, optical and hydrogen storage properties of XMoH 3 (X = Na, K, Rb, Cs) for the first time. Our calculated formation energy, elastic constants and phonon spectra show that XMoH 3 perovskites are thermodynamically, mechanically, and dynamically stable. The investigation of B/G ratio, Cauchy pressure and Poisson's ratio shows that NaMoH 3 , KMoH 3 and RbMoH 3 are brittle materials, while CsMoH 3 is the tough material. In addition, the anisotropy factor, wave velocity and Debye temperature of these hydrides were calculated. The band structures of XMoH 3 hydrides suggest that KMoH 3 and RbMoH 3 are metallic materials, while NaMoH 3 and CsMoH 3 are half-metallic compounds. The optical properties of these hydrides in the range of 0 – 40 eV were studied. We found that these compounds own high polarization and high reflection. The gravimetric hydrogen storage capacities of NaMoH 3 , KMoH 3 , RbMoH 3 and CsMoH 3 are 2.48 wt%, 2.19 wt%, 1.64 wt% and 1.30 wt%, respectively, and their hydrogen desorption temperatures are 498 K, 413 K, 385 K and 345 K, respectively. The thermodynamic properties, including entropy, free energy, enthalpy and heat capacity of XMoH 3 were also investigated. Our studies indicate that NaMoH 3 has the highest potential as an efficient hydrogen storage material. • XMoH 3 (X = Na, K, Rb, Cs) perovskites have been investigated using first-principles. • XMoH 3 compounds exhibit thermodynamic, mechanical, and dynamical stability. • The gravimetric hydrogen storage capacity is found to be 2.48 wt% for NaMoH 3. [ABSTRACT FROM AUTHOR]

Influenza poses a significant threat to global health, with the ability to cause severe epidemics and pandemics. The polymerase basic protein 2 (PB2) of the influenza virus plays a crucial role in the viral replication process, making the CAP-binding domain of PB2 an attractive target for antiviral drug development. This study aimed to identify and evaluate potential inhibitors of the influenza polymerase PB2 CAP-binding domain using computational drug discovery methods. We employed a comprehensive computational approach involving virtual screening, molecular docking, and 500 ns molecular dynamics (MD) simulations. Compounds were selected from the Diverse lib database and assessed for their binding affinity and stability in interaction with the PB2 CAP-binding domain. The study utilized the generalized amber force field (GAFF) for MD simulations to further evaluate the dynamic behaviour and stability of the interactions. Among the screened compounds, compounds 1, 3, and 4 showed promising binding affinities. Compound 4 demonstrated the highest binding stability and the most favourable free energy profile, indicating strong and consistent interaction with the target domain. Compound 3 displayed moderate stability with dynamic conformational changes, while Compound 1 maintained robust interactions throughout the simulations. Comparative analyses of these compounds against a control compound highlighted their potential efficacy. Compound 4 emerged as the most promising inhibitor, with substantial stability and strong binding affinity to the PB2 CAP-binding domain. These findings suggest that compound 4, along with compounds 1 and 3, holds the potential for further development into effective antiviral agents against influenza. Future studies should focus on experimental validation of these compounds and exploration of resistance mechanisms to enhance their therapeutic utility. [ABSTRACT FROM AUTHOR]

Background: Longevity is increasing worldwide due to improvements in healthcare and living standards. Aging is often associated with disability and multiple health concerns. To address these challenges, effective interventions are essential. This study investigated potential age-related declines in gait, balance, and strength. We also sought to assess any relationships between these three parameters and explore potential differences between women and men. Methods: Healthy individuals over 50 years of age were recruited for this cross-sectional study. Upper extremity (grip) strength and lower extremity (knee) strength of the dominant side were measured. Static balance was performed on the force plate in different situations each for 30 seconds: bilateral stance with eyes open, bilateral stance with eyes closed, as well as dominant leg and non-dominant leg unilateral stance with eyes open. Gait was measured during level walking using an optical motion capture system. Additionally, the dynamic stability margin (DSM) was calculated for the level walking trials. Results: The study results indicated that gait parameters were not significantly affected by age (p≥0.12), while knee and grip strength, along with several balance parameters, showed a significant decline with age. All individuals were able to maintain their bipedal balance, but their center of pressure movement increased significantly by age (p≤0.028). Z-scores were calculated to compare significant age parameters. Unipedal stance time was found to be the most affected by age compared to other contributing factors (p≤0.001). The duration of unipedal balance showed the most significant change per decade (non-dominant: -0.62 SDs; dominant: -0.53 SDs), while strength measures exhibited the lowest amount of change per decade (grip strength: -0.34 SDs; knee strength: -0.26 SDs). Sex differences were observed exclusively in strength parameters, with no discernible impact on the decline in balance parameters. Conclusions: These findings suggest that the duration of unipedal stance can serve as a reliable and gender-independent measure of neuromuscular aging for both elderly male and female subjects. [ABSTRACT FROM AUTHOR]

In this study, an aging asphalt mixture was regenerated by a waste-based rejuvenator and cemented by solid waste-based solidification materials (SSMs). A splitting test, wheel tracking test, and three-point bending test were conducted to evaluate the properties of the regenerated asphalt mixture (RAM). The results reveal that the properties of the asphalt mixture were not diminished or were moderately enhanced by the 30% substitution of RAP. With the substitution of RAP to 100%, the splitting tensile strength, dynamic stability, and splitting strength ratio were decreased by 13%, 15%, and 5%, respectively. With the 100% substitution of SSMs for cement, the compressive strength, dynamic stability, flexural strain, and splitting strength ratios of the RAM were increased by 40%, 32%%, 14%, and 8%, respectively. The lightweight components can be supplemented, and low-temperature deformation and interlayer flowability can be improved by the incorporation of the rejuvenator. The generation of hydrated calcium silicate and ettringite for SSMs is greater than those of cement. The massive generation of ettringite has been observed to increase the solid phase volume by 120%, which may facilitate a more complete filling of the remaining pores in the RAM due to water evaporation. The regeneration and cement on green and the high performance of the rejuvenator and the SSM markedly enhanced RAM performance. [ABSTRACT FROM AUTHOR]