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In this work, we have studied the spin dynamics of a synthetic antiferromagnet (AFM)/heavy metal/ferromagnet double barrier magnetic tunnel junction in the presence of Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction, interfacial Dzyaloshinskii–Moriya (iDM) interaction, Néel field, and Spin–Orbit Coupling (SOC) with different Spin-Transfer Torque (STT). We employ the Landau–Lifshitz–Gilbert–Slonczewski equation to investigate the AFM dynamics of the proposed system. We found that the system exhibits a transition from regular to damped oscillations with the increase in strength of STT for systems with a weaker strength of iDM interaction than RKKY interaction while displaying sustained oscillations for systems having the same order of RKKY and iDM interactions. On the other hand, the systems with sufficiently strong iDM interaction strength exhibit self-similar but aperiodic patterns in the absence of the Néel field. In the presence of the Néel field, the RKKY interaction dominating systems exhibit chaotic oscillations for low STT but display sustained oscillations under moderate STT. Our results suggest that the decay time of oscillations can be controlled via SOC. The system can work as an oscillator for low SOC but displays non-linear characteristics with the rise in SOC for systems having weaker iDM interaction than RKKY interactions. In contrast, opposite characteristics are noticed for iDM interaction dominating systems. We found periodic oscillations under low external magnetic fields in RKKY interaction dominating systems. However, moderate fields are necessary for sustained oscillation in iDM interaction dominating systems. Moreover, the system exhibits saddle-node bifurcations and chaos under moderate Néel field and SOC with suitable RKKY and iDM interactions. In addition, our results indicate that the magnon lifetime can be enhanced by increasing the strength of iDM interaction for both optical and acoustic modes. [ABSTRACT FROM AUTHOR]

Metasurface that achieves extraordinary terahertz transmission (ETT) and local electric field enhancement (FE) holds significant potential for terahertz studies involving extremely low concentrations of target materials. In this study, we explore a composite aperture metasurface capable of both ETT and local FE. By inserting bow-tie apertures in the "minimum-resonance" zone between four adjacent rhombic lattices, a local FE factor is achieved. Notably, adjusting the configuration of the bow-tie aperture enhances the coupling between surface plasmons, thereby expanding the transmission bandwidth. Through parameter optimization, the metasurface achieves a peak transmission exceeding 95% and a transmittance above 80% in the frequency range of 2.44–3.65 THz, while simultaneously exhibiting a maximum local FE factor of 1005 at 3.45 THz. This approach offers a promising avenue for the design of metasurfaces for spectroscopy and biosensor applications. [ABSTRACT FROM AUTHOR]

We report improved thermoelectric (TE) properties of mesostructured silicon powder arrays simply prepared by die-pressing without sintering. In contrast to bromoethane's modest effect, the symmetric dibromoethane molecule coupling could significantly increase the conductivity of Si powder array TE device, from 12.7 S cm−1 of a silicon powder array to 62.3 S cm−1, which is possibly caused by the high electronic transmission probability of symmetric organic molecule–Si crystal coupling, and additionally enhanced by Si bandgap narrowing and defect states of an organic–inorganic interface identified by UV–vis absorption spectra and photoluminescence spectroscopy. Boosted by the very low thermal conductivity (0.58 W m−1 K−1), the dimensionless figure of merit, the ZT value of an Si powder array remotely doped by dibromoethane, ∼0.173, was obtained at 385 K, which is about 17 times higher than that of the bulk Si. An Si–organic hybrid TE device shows potentials to approach the threshold of practical applications with moderate ZT performance and low cost. [ABSTRACT FROM AUTHOR]

In this study, we report giant nonreciprocal transmission of shear-horizontal surface acoustic waves (SH-SAWs) in a ferromagnetic bilayer structure with negative–positive magnetostriction configuration. Although the directions of magnetization in the neighboring layers are parallel, SH-SAWs can excite optical-mode spin waves (SWs) via magnetoelastic coupling at relatively low frequencies, which is much stronger than acoustic-mode SWs at high frequencies. The measured magnitude nonreciprocity or isolation of SH-SAWs exceeds 40 dB (or 80 dB/mm) at 2.333 GHz. In addition, maximum nonreciprocal phase accumulation reaches 188° (376°/mm). Our theoretical model and calculations provide an insight into the observed phenomena and demonstrate a pathway for further improving nonreciprocal acoustic devices toward highly compact microwave isolators and circulators. [ABSTRACT FROM AUTHOR]

Carbonyl groups (C=O) play crucial roles in the photophysics and photochemistry of biological systems. O1s x-ray photoelectron spectroscopy allows for targeted investigation of the C=O group, and the coupling between C=O vibration and O1s ionization is reflected in the fine structures. To elucidate its characteristic vibronic features, systematic Franck–Condon simulations were conducted for six common biomolecules, including three purines (xanthine, caffeine, and hypoxanthine) and three pyrimidines (thymine, 5F-uracil, and uracil). The complexity of simulation for these biomolecules lies in accounting for temperature effects and potential tautomeric variations. We combined the time-dependent and time-independent methods to efficiently account for the temperature effects and to provide explicit assignments, respectively. For hypoxanthine, the tautomeric effect was considered by incorporating the Boltzmann population ratios of two tautomers. The simulations demonstrated good agreement with experimental spectra, enabling differentiation of two types of carbonyl oxygens with subtle local structural differences, positioned between two nitrogens (O1) or between one carbon and one nitrogen (O2). The analysis provided insights into the coupling between C=O vibration and O1s ionization, consistently showing an elongation of the C=O bond length (by 0.08–0.09 Å) upon O1s ionization. [ABSTRACT FROM AUTHOR]

Antimonene, a promising conductor for next-generation 2D-based devices, has its contact resistance significantly influenced by the van der Waals (vdW) interaction within its heterostructure. In this study, we report the quantification of the vdW coupling between multilayer antimonene and bilayer MoS2 by ultrafast coherent vibration spectroscopy. By utilizing a femtosecond laser, we excited coherent acoustic vibrations in the multilayer-antimonene on substrate-supported bilayer MoS2, and the relative displacement at the vdW heterojunction was detected with the aid of bilayer MoS2. The photoexcited strain pulse generated in the multilayer-antimonene was observed as it transported to the bilayer MoS2, explaining the distortion at the beginning of the oscillation. By analyzing the thickness-dependent oscillation frequencies, we determine the effective vdW elastic constant between multilayer-antimonene and MoS2 to be (1.9 ± 0.2) × 1018 N/m3. This non-destructive optical technique offers a significant advance in the evaluation of vdW interactions at 2D metal-semiconductor interfaces. [ABSTRACT FROM AUTHOR]

The elasticities of double-stranded (ds) DNA and RNA, which are critical to their biological functions and applications in materials science, can be significantly modulated by solution conditions such as ions and temperature. However, there is still a lack of a comprehensive understanding of the role of solvents in the elasticities of dsRNA and dsDNA in a comparative way. In this work, we explored the effect of ethanol solvent on the elasticities of dsRNA and dsDNA by magnetic tweezers and all-atom molecular dynamics simulations. We found that the bending persistence lengths and contour lengths of dsRNA and dsDNA decrease monotonically with the increase in ethanol concentration. Furthermore, the addition of ethanol weakens the positive twist–stretch coupling of dsRNA, while promotes the negative twist–stretch coupling of dsDNA. Counter-intuitively, the lower dielectric environment of ethanol causes a significant re-distribution of counterions and enhanced ion neutralization, which overwhelms the enhanced repulsion along dsRNA/dsDNA, ultimately leading to the softening in bending for dsRNA and dsDNA. Moreover, for dsRNA, ethanol causes slight ion-clamping across the major groove, which weakens the major groove-mediated twist–stretch coupling, while for dsDNA, ethanol promotes the stretch–radius correlation due to enhanced ion binding and consequently enhances the helical radius-mediated twist–stretch coupling. [ABSTRACT FROM AUTHOR]

Material flow in the actomyosin cortex of a cell, during cell division, has been found to be chiral in nature. It has been attributed to active chiral torques generated in the actomyosin cortex. Here, we explore the possible signature of such chirality during the growth of the intra-cellular membrane partition, which physically divides the cell into two compartments. We use standard hydrodynamic theory of active gel to predict possible chiral flow structures in the growing partition. While the flows in the growing annular-shaped membrane partition is believed to be radial, it can also develop non-zero azimuthal velocity components (rotation) due to chirality. We show that the direction of rotation (clock or anti-clockwise) will not solely be decided by the sign of the active chiral torque but also by the relative strengths of rotational viscosity and flow coupling parameter. [ABSTRACT FROM AUTHOR]

The side chain dynamics of poly(quinoxaline-2,3-diyl)s (PQXs) are expected to influence their conformation. To investigate these dynamics experimentally, quasielastic neutron scattering (QENS) was performed for PQXs in deuterated tetrahydrofuran (THF-d8) and deuterated 1,1,2-trichloroethane/THF (1,1,2-TCE-d3/THF-d8), in which they formed right-handed and left-handed helical structures, respectively. The mean-square displacement of the PQX side chains in 1,1,2-TCE-d3/THF-d8 was lower than that in THF-d8. Furthermore, QENS complementary studies and molecular dynamics simulations unraveled a coupling between the main-chain and side chain dynamics of PQXs, suggesting the possibility of controlling the main-chain helical chirality through the dynamics of chiral side chains. These insights present a novel strategy for the design of synthetic helical macromolecules with precise chirality control. [ABSTRACT FROM AUTHOR]

As an innovative neural modulation technique, the transcranial magneto-acousto-electric (MAE) stimulation (TMAES) realizes the synergistic regulation of neuronal discharge through the ultrasonic mechanical and inductive electric effects, offering significant prospects in biomedical applications. However, the stimulation accuracy is still limited by the unidirectional distribution of MAE field intensity. A method of constructing center-converging MAE field by coupling the helical wave fronts of focused acoustic-vortex (FAV) beams with a coaxial magnetic field is proposed. By describing FAVs with Laguerre–Gaussian functions, the theory of MAE field construction is derived in explicit formulae and the spatiotemporal characteristics of MAE fields in the focal region are analyzed. It is theoretically and experimentally demonstrated that the MAE field generated by the FAV of lth order is determined by those of (l − 1)th and (l + 1)th orders. The center-converging phase-rotating MAE field can only be generated by the FAV of first order, maintaining a constant peak intensity at the vortex center. Experimental distributions of MAE fields for FAVs of different orders show good agreements with numerical simulations. With the peak pressure of 0.86 MPa and the magnetic intensity of 0.3 T, the peak intensity of 62.1 mV/m reaching the electric stimulation threshold is achieved. The center-converging MAE field constructed by FAV may develop a new synergistic neural modulation scheme for TMAES with enhanced precision and flexibility while ensuring safety and efficacy, thereby exhibiting significant scientific and practical implications. [ABSTRACT FROM AUTHOR]

Planar piezoelectric actuators, which can achieve high-precision motions over a wide range, have been widely applied in high-end equipment fields. However, the existing planar piezoelectric actuators can no longer meet the high actuation characteristics required for the rapidly development of these fields, which include large travel, high resolution, fast speed, planar three degrees of freedom (3-DOF) and a compact structure. A planar piezoelectric actuator with resonant actuation is proposed and tested in this work. The actuator consists of four symmetrically configured uniform bending-bending hybrid piezoelectric units, which coordinate to achieve large travel and planar 3-DOF characteristics. A vibration isolation mechanism adopting thin beam structure with low stiffness in coupling directions is designed to achieve vibration isolation among the units. The actuator can operate in high frequency resonance mode and low frequency stepping mode, allowing for the achievement of high-speed and high-resolution characteristics. A prototype is fabricated and tested. A compact structure measuring 53 mm × 53 mm × 13 mm and weighing only 30.2 g has been achieved. The maximum linear and rotary speeds have been tested to be over 400 mm/s and 13 rad/s, respectively. The linear and rotary resolutions are 0.42 μm and 12.9 μrad, respectively. The proposed actuator achieves characteristics of large travel, high resolution, fast speed, 3-DOF and a compact structure. [ABSTRACT FROM AUTHOR]

In this paper, new series of high temperature piezoelectric ceramics consisting of (0.975- x)BiScO 3 - x PbTiO 3 -0.025 Pb(Sn 1/3 Nb 2/3)O 3 (BS- x PT-0.025PSN), have been fabricated and investigated in detail. The phase structure analysis and electrical properties characterization at room temperature demonstrate the MPB composition is BS-0.62PT-0.025PSN with the optimum piezoelectric performance (d 33 523 pC/N, large-signal d 33 * 734 p.m./V, and k p 54.6%), which are superior than the unmodified BS-PT ceramics. Interestingly, the in situ electromechanical coupling properties exhibits good stability with the variation lower 5% as the temperature increasing from room temperature to 300 °C and the d 33 * reaches the maxima of 1413 p.m./V at 200 °C, and remains 743 p.m./V even at 300 °C, showing the BS-0.62PT-0.025PSN ceramics potential for high temperature piezoelectric actuator application together with the Curie temperature of 418 °C and the high temperature annealing stabilities. Then a 10-layer stack-type piezoelectric actuator was designed and fabricated based on the BS-0.62PT-0.025PSN ceramics, which can be operated steadily up to 200 °C and produces a displacement of 24 μm under the driven electric field. The maximum displacement 32.4 μm of the actuator was obtained at the testing temperature of 150 °C, far more than that of the value at the room temperature. The BS-0.62 PT-PSN ceramics and their stack-type piezoelectric actuator maybe a strong supplement to satisfy the urgent demand for high temperature piezoelectric actuator. [ABSTRACT FROM AUTHOR]

This paper presents a novel Flexnertia metastructure concept to perform vibration suppression through coupling rotational inertia to structural flexural motion. Theoretical analysis and experimental test of the proposed metastructure with emphasis on dissipating structural flexural motion is exhibited, showing vibration control performance. The experimental and numerical results are in good agreement, both confirming that the average overall response of the metastructure is significantly reduced. The attenuation becomes most pronounced in the low-frequency range where structures tend to suffer most due to high response around the regime of the first flexural modes. [ABSTRACT FROM AUTHOR]

An analytical and numerical formalism is developed to study the influence of the various positions of substitution atoms B on the scattering and transmission vibration modes in quasi-1D monatomic structures A. The matching technique is employed to calculate the dynamical properties and transmittance spectra of two substituted atomic sites. The theoretical formalism gives a complete description of the lattice dynamics and the vibration-waves propagation in the presence of the impurity sites. Numerical calculations are performed for three different positions of the two substituted atoms B in the low-dimensional structure consisting of double monatomic parallel chains. First, we examine the position where the two B atoms are adjacent in the y-direction, afterwards, we place the two sites side by side in the x-direction. Lastly, the two sites are placed in oblique configuration. The obtained results show that phonons associated to the inhomogeneous structures are strongly dependent on the scattering frequency, elastic force parameters and the position of the atomic substituted sites. In the three considered positions, the presence of the B atoms gives rise to localized vibration effects. The fluctuations observed in the vibration spectra are related to resonances due to the coherent coupling between travelling phonons and the localized vibration modes in the neighborhood of the impurity sites. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a battery‐free ultra‐low‐power (ULP), highly integrated, and wide‐bandwidth low‐IF radio‐frequency (RF) receiver designed for millimeter‐wave (mm‐Wave) applications, utilizing 130‐nm CMOS technology. The suggested RF receiver is suitable for K‐band (n258) at 26 GHz, Ka‐band (n261 and n257) at 28 GHz, and the LMDS band at 28 GHz in fifth‐generation applications. The proposed radio receiver consists of a low‐noise driver stage implemented using a complementary current‐reuse common gate with an active shunt feedback configuration and an in‐phase/quadrature‐phase (I/Q) demodulator. The proposed RF receiver employs transformer coupling to isolate the DC path between the transconductance stage (RF stage) and the switching stage (IF stage). The driver stage expands the RF input impedance while maintaining acceptable linearity and gain with ultra‐low DC power dissipation. The DC supplies for the proposed mm‐Wave RF receiver are generated using two novel energy‐harvesting voltage doubler circuits to provide positive and negative voltages. The proposed mm‐Wave radio receiver consumes 0.475 mW from a 1.1 V DC supply and exhibits a power conversion gain (CG) of 6.3 dB, with a 3 dB frequency bandwidth extending from 22 to 32 GHz. The input 1‐dB compression point (P1dB) of the RF receiver is −2.65 dBm, and the input third‐order intercept point (IIP3) is 7.35 dBm. With a sensitivity of −66.5 dBm at a 100 MHz channel bandwidth and a dynamic range of 63.85 dB, the suggested receiver demonstrates notable performance characteristics. The proposed radio receiver boasts an excellent figure of merit (FoM) at 215 dB, surpassing published works by a margin of 8–31 dB. The primary positive supply voltage is derived from a double‐band positive voltage doubler with series resonance feedback and parallel resonance networks, efficiently achieving the desired DC voltage and output current (1.1 V and 450 μA). Meanwhile, the negative gate bias is provided by a negative voltage doubler, ensuring the necessary negative voltage (−0.5 V) without any current conditions. [ABSTRACT FROM AUTHOR]

Summary: Inductive power transmission (IPT) and capacitive power transmission (CPT) are currently the two main wireless power transfer technologies. Hybrid power transmission (HPT) systems that combine IPT and CPT can improve transmission performance and are more attractive for some charging applications such as electric bicycles (e‐bikes). However, HPT systems are more sensitive to parameter variations, and the coupling mechanism is prone to misalignment during wireless charging. Therefore, achieving stable output power and constant transfer efficiency over a wide range of coupling coefficient variations is still a major challenge for HPT systems. In this work, the parity–time (PT) symmetry theory is applied to an SS‐type HPT system, and a circuit model of the PT‐based HPT system is developed by using coupling capacitance and coupling inductance. The effect of connecting the plates to the homonymous end or heteronymous end of the coupling coils on the PT symmetry range of the HPT system is discussed. It is found that the heteronymous end connection of the coils can effectively increase the range of constant output power and stable transfer efficiency. Finally, a prototype is built to verify the feasibility and effectiveness of the proposed PT‐based HPT system. The transfer power and efficiency remain constant in the PT‐symmetric range, and the inductive and capacitive coupling coefficients are smaller compared to IPT and CPT systems with the same parameters. [ABSTRACT FROM AUTHOR]

The operation condition of axle-box bearings strongly affects the running safety of vehicles. However, the presence of rail welds can impact the wheel-rail interaction system, causing changes in the dynamic response of axle-box bearings and furtherly affecting their health condition. Despite this, there is still a lack of discussion and analysis on the effect of rail welds on dynamic characteristics of axle-box bearings. Therefore, a vehicle-track coupling dynamics model is developed. Besides the rigid vehicle model, flexible track model and wheel-rail contact model, the axle-box bearing model and flexible wheelset model are considered. Among them, the axle-box bearing model accounts for the motion of the roller and cage decentralized into multiple segments. Using modal superposition method, the flexible deformation of the wheelset is calculated and overlapped with its rigid displacement for the flexible wheelset model. The performance of the model is verified through theoretical analysis and field tests. It is crucial to consider the wheelset as flexible in the presence of rail welds and its effects are also researched. Moreover, the effect of the rail weld geometry on the wheel-rail separation is studied, and the consequence caused by rail welds on the bearing damage is discussed under different vehicle speeds. [ABSTRACT FROM AUTHOR]

Considering the intricate design of the conventional inerter structures, the compressive-torsional coupling effects of chiral metamaterial are used to achieve the torsional movement alongside linear movement, forming a simplified inerter mechanism. This simplified design is then integrated with the nonlinear energy sink (NES). In this study, a novel NES with the chiral metamaterial inerter structure is suggested to mitigate vibrations in the cantilever beam system. The introduction includes both the piecewise linear beam, providing nonlinear stiffness, and the chiral metamaterial inerter structure. These components are combined to form the piecewise nonlinear NES with inerter (PNESI) structure. Subsequently, the PNESI structure is integrated with the cantilever beam system, and a corresponding dynamic model is formulated to evaluate its vibration mitigation capabilities. The theoretical results are verified through experiments. The findings indicate that under steady-state vibration conditions, PNESI achieves peak vibration reductions of 88.6% in simulations and 62.7% in experiments for the cantilever beam system. [ABSTRACT FROM AUTHOR]

Chinese actors have emerged as major funders and developers of large-scale transnational infrastructure projects in Europe and beyond. Despite this profound shift, geographers have not yet arrived at a clear conceptualisation of such projects. We show how the literature is overly reliant on a functional view of the Chinese state, structural economic factors, single case studies, and bilateral relations, generating monocausal explanations of outcomes. We develop a new conceptual framework emphasising variegation driven by shifting assemblages of actors, dynamic strategic coupling, and multi-scalar processes of territorialisation. To operationalise our framework, we draw on process tracing and incorporated comparisons across cases. [ABSTRACT FROM AUTHOR]

The effect of thermo-mechanical load coupling and porosity distributions on vibration and buckling characteristics of Functionally Graded Sandwich Plates (FGSPs) with cutouts is investigated by Finite Element (FE) formulation. Two sandwich configurations are considered and physical neutral surface is incorporated due to material asymmetry. Novel dynamic approach is proposed to evaluate buckling loads. Results obtained are compared with experimental, numerical solutions in literature and revealed that the FGSP buckling capacity under thermomechanical loads improves on using ceramic with lower thermal expansion coefficient. Also, at higher temperature rises, buckling capacity increases due to increasing porosity content, whereas capacity reduces at lower temperature rises. [ABSTRACT FROM AUTHOR]

We investigate theoretically an optomechanical system composed of an optical mode and a mechanical mode interacting through first-order coupling and second-order coupling in the presence of a Kerr nonlinear medium. We study how the nonlinearities (second-order optomechanical coupling and Kerr nonlinearity) alter the optical output spectrum, optical quadrature squeezing and optomechanical entanglement. It is shown that the intensity of the output optical spectrum decreases drastically with an increase in second-order optomechanical coupling while it increases significantly with an increase in Kerr nonlinear parameter. More interestingly, by choosing suitable second-order optomechanical coupling and detuning of the optical cavity field, one can achieve strong squeezing of the cavity light field. Further, these nonlinearities play an important role in creating robust optomechanical entanglement between optical and mechanical modes. Hence, the presence of various nonlinearities in the system can be a good platform for achieving the squeezing of light and robust optomechanical entanglement which can be used in realizing better quantum optomechanical devices. [ABSTRACT FROM AUTHOR]

Significant progress has been made in understanding the mechanisms and simulations of ice-induced shock vibrations due to continuous experimentation and simulation of vibrations induced by ocean platforms. However, the threat of such vibrations to bridges in cold regions with spring rivers remains significant. Currently, challenges persist in the numerical analysis methods applied to vibrations caused by collisions between ice and bridges in river channels. This difficulty primarily arises from the insufficient consideration of the impact of flow field coupling on ice-induced shock vibrations under various simulation conditions. This paper aims to analyze the influence of ice-induced shock vibrations arising from collisions involving bridges, ice, water, and air. It also compares the Semi-Arbitrary Lagrangian-Eulerian (S-ALE) and Arbitrary Lagrangian-Eulerian (ALE) methods, finding that the S-ALE method is better suited for complex flow-solid coupling analysis under the same model. Comparative analysis shows that the fluid effect period increased by approximately 30%, resulting in an 8% reduction in peak values. This confirms the applicability of the ice-induced shock vibration theory and demonstrates that factors such as velocity and thickness significantly impact these vibrations. The findings offer valuable insights for the numerical simulation of river ice-induced shock vibrations due to bridge-ice collisions in cold areas. [ABSTRACT FROM AUTHOR]

Mechanical correlation bias is inherent in audit pricing studies when independent variables (X) are derived from firm level audit fees (Y). Such variables are endogenous by construction leading to biased estimates, since (mechanically) X determines Y and Y determines X. After reviewing the extant auditing/accounting literature where mechanical correlation obtains we employ mathematical derivations and simulations to quantify the bias associated with a range of mechanically correlated market competition and industry specialist variables. Since auditor market competition variables are important to regulators and antitrust authorities, we analyze the mechanical correlation issue with regard to an extant study which introduces a novel measure of audit market competition (derived from audit fees). The study provides evidence that smaller incumbent auditors are pressured into offering lower fees when competing against a large local audit firm. However, when the current client's audit fee is 'decoupled' from this new competition measure to mitigate bias, it is statistically insignificant in our multivariate regression analysis. Additionally, we employ auditee sales and total assets to construct proxies for competition variables (which are not mechanically correlated) and find them to be statistically insignificant. We conclude with suggestions of how to address the issue of mechanical correlation in future studies. [ABSTRACT FROM AUTHOR]

It is expensive that each consuming power equipment needs to equip a separate wireless power charger. In addition, obtaining constant output power and high transfer efficiency in large coupling variation ranges is challenging. In this study, the two-load transmission characteristics of a WPT system with double transmitting coils are studied. The circuit model of the two-load WPT system is first developed, and the transmission characteristics are studied. The two-load WPT system achieving constant output power and transmission efficiency is then studied. Finally, the two-load WPT experimental system is designed. This system can achieve self-adjusting impedance compensation. Moreover, constant output power and transmission efficiency are achieved in each receiver, where their fluctuations are less than 5%. Furthermore, the utilization of the charger is improved by more than 8% due to the two receivers. This topology can provide a solution for practical application problems, such as the two-load wireless charger of the vehicle mobile phone [ABSTRACT FROM AUTHOR]

The present paper describes an inverse analysis technique to obtain material flow stress law from experimental measurements of rolling torque. This was developed by coupling a mathematical model of rolling, able to predict rolling torque, with a mathematical optimizer which minimizes the difference between experimental values and model prediction in terms of torque using an objective function. It is known that FEM is able to well predict forming loads and material behavior in the rolling process with high accuracy. For this reason, numerical tests were performed using FEM in order to obtain rolling torque values in place of experimental measurements, to validate the developed strategy. [ABSTRACT FROM AUTHOR]

Power converters can perform power conversion and data transmission simultaneously. With the aim of mitigating the hardware requirements of vehicle power line communication (VPLC), a novel VPLC scheme based on switching ripple modulation (SRM) is proposed to eliminate the need for coupling circuits and specialized communication chips. By embedding data modulation techniques into traditional pulse width modulation systems, power/data multiplexing transmission is achieved by demodulating the voltage ripple on the DC bus. First, the theoretical foundation of the SRM is introduced, and power/data single carrier modulation using 2FSK and data demodulation based on the sliding discrete Fourier transform are provided. Subsequently, comprehensive analyses of the mutual influence between power conversion and communication in the buck converter are conducted. The impact of power conversion on communication primarily depends on the control loop compensation and perturbation depth. Moreover, the designs of the ripple conditioning circuit and communication frame are presented. Finally, an experimental prototype is constructed with two buck converters in parallel. The experimental results demonstrate a data transmission rate of 12.5 kbps within 3 m under steady‐state, transient input and output voltage, and transient load conditions, validating the correctness of the proposed methodology. [ABSTRACT FROM AUTHOR]

At present, most of the analyses or studies about inductive power transfer (IPT) with constant current (CC) output and constant voltage (CV) output are carried out without considering misalignment conditions or different gaps. An IPT system satisfying battery charging demand and anti‐misalignment requirements simultaneously is infrequent. This paper proposes a multi‐objective particle swarm optimization method of IPT reconfigurable topology to realize CC and CV modes at varying resistance conditions and wide coupling ranges. The output characteristics of an inductor–capacitor–capacitor (LCC)–LCC compensation circuit have been explored, and it is found that the secondary‐side compensated capacitors have a greater impact on the output power, which can be used to improve power regulation ability accompanied by coupling varying. Eight optimization compensated parameters of the reconfigurable topology are obtained from the Pareto front to achieve the required CC and CV charging outputs. By switching the compensated capacitors, the selected parameters can make the current and voltage fluctuation less than 9.3% and 7.9%, respectively, during the coupling charging range from 0.3 to 0.22. Moreover, primary zero voltage switching operation is achieved to enable high efficiency. The simulation and the experimental verification are carried out to verify the validity of the proposed method. [ABSTRACT FROM AUTHOR]

In the realm of wireless power transfer, considering misalignment between transmitting and receiving coils is imperative. Traditional wireless power transfer systems experience a significant decrease in output power when the coupling coefficient fluctuates. This paper proposes a reconfigurable dual‐frequency series–series (SS) topology with primary side inductive detuned and secondary side with full resonance. The proposed topology operates at two frequencies and can be transformed into two different SS topologies at each frequency. This allows the system to switch between the two SS topologies when a large misalignment occurs, thereby achieving a more stable output power level. Furthermore, a comprehensive parameter design flowchart for the proposed topology is presented, and the parameters for a 400 W prototype are designed and implemented. The prototype is tested to evaluate the performance of the topology. The frequency response analysis of the prototype validates the effectiveness of the parameter design method. The test results show that the topology can maintain output power fluctuations within 23% of the maximum power for misalignment ranging from k = 0.13 to k = 0.46. Additionally, the system maintains an efficiency of at least 80% across the entire output power flat range, peaking at a maximum efficiency of 91%. [ABSTRACT FROM AUTHOR]

This study developed a rigid-flexible coupling vibration model for a rotating functionally graded geometrically imperfect microbeam, integrating refined shear deformation theory (RSDT), the von Kármán nonlinear assumption, and modified couple stress theory. The material properties are described by a power-law distribution along the thickness. Utilizing RSDT, deformation was characterized by axial tensile, chordwise bending, and shear variables. The energy of the microbeam was discretized through assumed modal functions that satisfy cantilever beam boundary conditions, and the governing equations were derived using the Lagrange equation, subsequently solved with the complex modal space method. After validating the model, the effects of shear and geometric imperfections on dimensionless natural frequencies and mode shapes were analyzed, taking into account dynamic stiffening, gradient index, and size effects. Key findings include: (i) shear and imperfections reduced the rotational speed, gradient index, and material length scale required for frequency locus veering; (ii) dynamic stiffening and size effects suppressed the influence of shear and imperfections; (iii) larger imperfections initially increased, then decreased, their impact on chordwise deformation modes as the gradient index increases; (iv) coupling between chordwise and axial motions leads to mode transition with increasing imperfection amplitude. This work provided theoretical guidance for addressing the disorder problem of system parameters in micro-electromechanical systems-based devices. [ABSTRACT FROM AUTHOR]

ABSTRACT The dynamic response of a torsionally loaded pile embedded in heterogeneous soil is investigated in this paper based on a new theoretical model of the dynamic pile–soil interaction with consideration of the continuity of heterogeneous soil. By conceptualizing the surrounding soil as an elastic continuum with shear modulus following a power law variation along the depth, a new governing equation is established to portray the dynamic torsional deformation of the heterogeneous soil. With coupling of the pile motion under dynamic torque, the theoretical solution of the torsional dynamic impedance of an end‐bearing pile embedded in heterogeneous soil is obtained by employing analytical techniques. Comparative analyses under varied conditions are conducted to authenticate the applicability and superiority of the proposed theoretical model. Parametric studies are performed via extensive arithmetic examples to decipher the mechanism of torsional vibration of the end‐bearing pile in heterogeneous soil. Conclusively, the significant influences of soil heterogeneity along depth on the dynamic response of torsionally loaded piles are identified, and the characteristics of the cut‐off frequency of the dynamic damping are elucidated in detail. The outcomes attained herein can serve to formulate guidelines for design and facilitate the evaluation of pile performance in practical applications. [ABSTRACT FROM AUTHOR]

This study presents the theoretical foundations of analogous electromagnetically induced transparency and absorption, which we refer to as coupling induced transparency (CIT) and absorption (CIA), respectively, along with an exploration of the transition between these phenomena. We provide a concise phenomenological description with analytical expressions for transmission spectra and dispersion, elucidating how the interplay of coherent and dissipative interactions in a coupled system results in the emergence of level repulsion (LR) and attraction (LA), corresponding to CIT and CIA, respectively. This theory comprehensively captures both the phenomena while modelling the microstrip line loaded resonators and their couplings systematically. The model is validated through numerical simulations using a hybrid system comprising a split ring resonator (SRR) and an electric inductive-capacitive (ELC) resonator in planar geometry. We analyse two cases while keeping the ELC parameters constant, one involving a dynamic adjustment of the SRR size with a fixed split gap, and the other entailing a varying gap while maintaining a constant SRR size. Notably, in the first case, the dispersion profile of the transmission signal demonstrates LR, while the second case results in LA, effectively showcasing CIT and CIA, respectively. These simulated findings not only align with the theoretical model but also underscore the versatility of our approach. Subsequently, we extend our model to a more general case, demonstrating that a controlled transition from CIT to CIA is achievable by manipulating the dissipation rate of individual modes within the hybrid system, leading to either coherent or dissipative interactions between the modes. Our results provide a pathway for designing hybrid systems that can control the group velocity of light, offering potential applications in the fields of optical switching and quantum information technology. [ABSTRACT FROM AUTHOR]

We select and investigate six global solar extreme-ultraviolet (EUV) wave events using data from the Solar Dynamics Observatory and the Solar and Heliospheric Observatory. These eruptions are all on the limb but recorded as halo coronal mass ejections (CMEs) because the CME-driven shocks have expanded laterally to the opposite side. With the limb observations avoiding the projection effect, we have measured the inclination and speed of the EUV wavefront from 1.05 to 1.25 R ⊙. We also investigate the coupling and connection of the EUV wavefront with the CME boundary and the CME-driven shock, respectively. The major findings in the six events are: (1) the forward inclination of the primary and coronal-hole-transmitted EUV wavefronts is estimated, respectively, and the origins of these inclinations and their effects on the estimate of actual wavefronts speed are investigated; (2) the wavefront speed can be elevated by loop systems near the coronal base, and the average speed in the low corona has no clear correlation with the lateral expansion of the CME-driven shock in the high corona; (3) the fast magnetosonic Mach number of the wavefront is larger than unity from the coronal base; (4) the EUV wavefront is coupled with the CME driver throughout the propagation in two events; (5) after the EUV wavefront vanishes, the CME-driven shock continues traveling on the opposite side and disconnects from the EUV wavefront in four events. These results and their implications are discussed, which provide insight into the properties of global EUV waves. [ABSTRACT FROM AUTHOR]

This paper proposes a universal vibroacoustic coupling theoretical analysis model for investigating the sound insulation characteristic of corrugated core sandwich panel (CCSP) under different boundary conditions. The vibroacoustic coupling model consists of CCSP (structural field) and two three-dimensional acoustic cavities which simulate the incident sound field and accept the sound field, respectively. Based on first-order shear deformation plate and shell theories and acoustic theory, the dynamic model of CCSP and three-dimensional acoustic cavities are established by employing the differential quadrature finite element method in conjunction with the energy principle. The coupling of CCSP and three-dimensional acoustic cavities is realized by the velocity continuity condition at the acoustic–structure interfaces. The validation of the vibroacoustic coupling model is verified by comparing the results calculated by the established model with the corresponding results calculated by ABAQUS. The influence of model parameters on the vibroacoustic characteristic of vibroacoustic coupling model is investigated systematically for determining the critical structure parameters which have influence on the vibroacoustic behaviors. The effect of critical structure parameters on the sound insulation characteristic of CCSP is analyzed systematically for the optimization of the sound insulation performance of CCSP and provides theoretical basis and technique guidance. [ABSTRACT FROM AUTHOR]

This study proposes a multi‐perspective fusion model for operating speed prediction based on knowledge‐enhanced graph neural networks, named RoadGNN‐S. By utilizing message passing and multi‐head self‐attention mechanisms, RoadGNN‐S can effectively capture the coupling impacts of multi‐perspective alignment elements (i.e., two‐dimensional design, 2.5‐dimensional driving, and three‐dimensional spatial perspectives). The results of driving simulation data show that root mean squared error, mean absolute error, mean absolute percentage error, and R‐squared values of RoadGNN‐S are superior to those of other classic deep learning algorithms. Then, prior knowledge (i.e., highway geometry supply, driver expectations, and vehicle dynamics) is introduced into RoadGNN‐S, and the models’ prediction accuracy and transferability are verified by field observation experiments. Compared to the above data‐driven models, knowledge‐enhanced RoadGNN‐S effectively avoids the fundamental errors, improving the R‐squared value in predicting passenger cars’ and trucks’ operating speed by 7.9% and 10.7%, respectively. The findings of this study facilitate the intelligent highway geometric design with multi‐perspective fusion and knowledge enhancement techniques. [ABSTRACT FROM AUTHOR]

Towards complex coupled molecular motions, the remote handedness inversion of a helicene moiety was achieved by a rotary molecular motor. The use of a specifically engineered dynamic helicene stator in a novel overcrowded‐alkene second‐generation molecular motor based on a fluorinated dibenzofluorene fragment allows for an unprecedented control over helicity inversion. This is achieved by the mechanical coupling of the rotation of the rotor to the helicene inversion of the stator half via a remote chirality transmission process. Thus, the unidirectional rotary motion generated upon irradiation is used to invert the dynamic stereochemistry of a helicene, leading to a 6‐step cycle with eight intermediates. In this cycle, both alternation between P and M configurations of the helicene stator and dynamic thermal interconversion (paddling motion) can be achieved. In‐depth computational and spectroscopic studies were performed to support the associated mechanism. The control over coupled motion and dynamic helicity offers prospects for the development of complex responsive systems. [ABSTRACT FROM AUTHOR]

AbstractOwing to its exceptional physical properties, graphene is considered as an excellent reinforcement for composite materials. However, the existing higher-order models encounter significant hurdles when attempting to accurately predict the natural frequencies of sandwich beams with graphene nanoplatelets reinforced composite (GNPRC) piezoelectric face sheets. If transverse shear deformations are not accurately modeled, the dynamic behavior of piezoelectric sandwich beams will be noticeably influenced by the disparities of material properties at the interfaces of adjacent layers, as well as the inherent electromechanical coupling characteristic. To overcome these challenges, an advanced electro-mechanical coupling theory will be introduced for the vibration analysis of sandwich beams featuring GNPRC piezoelectric face sheets. Compared to previous higher-order models, the proposed beam model introduces an enhanced interlaminar shear stress field incorporating electromechanical properties. This improved stress field can be involved in the equations of motion based on the Hamilton principle, significantly enhancing the precision in analyzing the free vibration behavior of piezoelectric sandwich beams. Furthermore, a simplification of finite element implementation can be achieved by removing the second-order derivatives of in-plane displacements from the transverse shear stress field. Consequently, a C0-type three-node beam element is constructed for the dynamic analysis of sandwich beams with GNPRC piezoelectric face sheets. To validate the performance of the proposed theory, the 3D elasticity solutions and results obtained from alternative theoretical frameworks are used. Numerical results demonstrate that the present model offers superior accuracy over the existing higher-order theories. Additionally, a comprehensive parametric investigation is conducted to explore the influence of key parameters on the free vibration characteristics of piezoelectric sandwich beams. [ABSTRACT FROM AUTHOR]

We are proposing a hybrid superconductor–semiconductor platform using indium arsenide (InAs) grown on an insulating layer of indium aluminum arsenide heterostructure (InAsOI) as an ideal candidate for coherent caloritronic devices. These devices aim to heat or cool electrons out of equilibrium with respect to the phonon degree of freedom. However, their performances are usually limited by the strength of the electron–phonon (e-ph) coupling and the associated power loss. Our work discusses the advantages of the InAsOI platform, which are based on the significantly low e-ph coupling measured compared to all-metallic state-of-the-art caloritronic devices. Our structure demonstrates values of the e-ph coupling constant up to two orders of magnitude smaller than typical values in metallic structures. [ABSTRACT FROM AUTHOR]

AbstractThe rotary vector reducer (RV reducer) is a key reduction mechanism for industrial robots, and its torsional stiffness directly determines positioning accuracy and dynamic characteristics. Unlike traditional time-varying torsional stiffness analysis methods considering limited factors and statics solution method, a time-varying torsional stiffness analysis method considering output torque variability and dynamic nonlinearity is proposed to assess the time-varying torsional stiffness of the reducer. Firstly, the rigid-flexible coupling multi-body dynamic model was built employing software ADAMS, with crank shaft and cycloidal gears being treated as flexible bodies. Its correctness was verified under standard condition through grey correlation theory and the torsional stiffness under different conditions was obtained, respectively. Secondly, a contact finite element model of the reducer was established, taking contact relationships between different shaft-gear-bearings into account. As a comparison, a rotating-join finite element model was also constructed. And their torsional stiffness under experimental condition was calculated. Finally, the torsional stiffness test was conducted to verify the accuracy of the three models under this condition. The results show that the time-varying torsional stiffness obtained by the proposed method is only 8.83% different from the test results and exhibiting a certain periodic pattern under standard conditions. [ABSTRACT FROM AUTHOR]

As ionic liquids (ILs) continue to be prepared, there is a growing need to develop theoretical methods for predicting the properties of ILs, such as gas solubility. In this work, different strategies were employed to obtain the solubility of CO2 and N2, where a conductor-like screening model for real solvents (COSMO-RS) was used as the basis. First, experimental data on the solubility of CO2 and N2 in ILs were collected. Then, the solubility of CO2 and N2 in ILs was predicted using COSMO-RS based on the structures of cations, anions, and gases. To further improve the performance of COSMO-RS, two options were used, i.e., the polynomial expression to correct the COSMO-RS results and the combination of COSMO-RS and machine learning algorithms (eXtreme Gradient Boosting, XGBoost) to develop a hybrid model. The results show that the COSMO-RS with correction can significantly improve the prediction of CO2 solubility, and the corresponding average absolute relative deviation (AARD) is decreased from 43.4% to 11.9%. In contrast, such an option cannot improve that of the N2 dataset. Instead, the results obtained from coupling machine learning algorithms with the COSMO-RS model agree well with the experimental results, with an AARD of 0.94% for the solubility of CO2 and an average absolute deviation (AAD) of 0.15% for the solubility of N2. [ABSTRACT FROM AUTHOR]

Sleep is essential for the optimal consolidation of newly acquired memories. This study examines the neurophysiological processes underlying memory consolidation during sleep, via reactivation. Here, we investigated the impact of slow wave - spindle (SW-SP) coupling on regionally-task-specific brain reactivations following motor sequence learning. Utilizing simultaneous EEG-fMRI during sleep, our findings revealed that memory reactivation occured time-locked to coupled SW-SP complexes, and specifically in areas critical for motor sequence learning. Notably, these reactivations were confined to the hemisphere actively involved in learning the task. This regional specificity highlights a precise and targeted neural mechanism, underscoring the crucial role of SW-SP coupling. In addition, we observed double-dissociation whereby primary sensory areas were recruited time-locked to uncoupled spindles; suggesting a role for uncoupled spindles in sleep maintenance. These findings advance our understanding the functional significance of SW-SP coupling for enhancing memory in a regionally-specific manner, that is functionally dissociable from uncoupled spindles. Simultaneous EEG-fMRI shows that slow wave-coupled sleep spindles promote region-specific memory reactivation after motor learning, revealing distinct roles for coupled vs. uncoupled spindles in sleep-dependent memory consolidation. [ABSTRACT FROM AUTHOR]

Nonlocal metasurfaces are currently emerging as advanced tools for the manipulation of electromagnetic radiation, going beyond the widely explored Huygens metasurface concept. Nonetheless, the lack of an unified approach for their fast and efficient tunability still represents a serious challenge to overcome. This study reports on the gigahertz modulation of a dielectric slab‐based, nonlocal (i.e., angle‐dispersive) metasurface, whose operation relies on the optomechanical coupling with a mechanical wave excited piezoelectrically by a transducer integrated on the same chip. Importantly, the metasurface region is free from any conductive material, thus eliminating optical losses, and making the device of potential interest for delicate environments such as high‐power apparatuses or quantum optical systems. [ABSTRACT FROM AUTHOR]

1D multiferroic fibers are known to exhibit attractive characteristics, including enhanced magnetoelectric (ME) coupling compared to thin film and bulk architectures. A comprehensive understanding of composite fibers, however, has been hindered by the complexity of their structure, leading to limited reports. Here, clear and strong ME coupling is experimentally detected in a composite Janus nanofiber aggregate using second harmonic generation (SHG) polarimetry under different magnetic field orientations. The observation of such a pronounced effect using an all‐optical method has not been previously reported in multiferroic fibers. A series of global fits is performed to the SHG polarimetry results to investigate the behavior of nanofibers within an aggregate. We find the magnetically assembled fibers exhibit semi‐cylindrical alignment as well as the expected lengthwise alignment despite variations in size and composition from fiber to fiber. The ME coupling and the semi‐cylindrical alignment seen in SHG are further corroborated via X‐ray diffraction under similar magnetic field conditions. These findings contribute to the development of complex composite and multifunctional devices using multiferroic nanostructures as building blocks, even those with inhomogeneous shapes and geometries. [ABSTRACT FROM AUTHOR]

The coupling model between unwinding tension and various factors is crucial for understanding warp beam unwinding characteristics and designing tension control systems. However, currently established models are simple and fail to reflect the complexity of the actual unwinding process. Additionally, the traditional unified PID control method for multiple warp beams is difficult to ensure stable unwinding tension for single warp beam, negatively impacting the quality and efficiency of the sizing process. To address these issues, coupling models between tension, radius, speed, turns and air pressure during the warp beam unwinding process were established and validated using constructed detection devices. Experimental results showed that the four types of measured warp beams fit the three coupling models with R 2 values exceeding 90%, confirming the accuracy of these models. Subsequently, a novel fuzzy adaptive PID control system for single warp beam unwinding tension was proposed based on these models. Unlike traditional methods that measure tension directly, the system utilizes unwinding turns detection device to monitor the real-time changes. Simulation results confirmed that the proposed system maintains constant tension under different reference tensions and unwinding radius. Compared to traditional PID control, it significantly reduces tension fluctuation, with reductions of 64.49% under different speed step disturbances and 23.66% under noise disturbances. The validated models and proposed tension control system in this paper provide a solid theoretical foundation and practical guidance for optimizing the new generation of sizing machines. [ABSTRACT FROM AUTHOR]

In polymer mechanochemistry, regulating the intrinsic mechanical reactivity of a mechanophore offers extensive opportunities in material science, enabling the development of hierarchical and multifunctional polymer‐based materials. Recent advances have focused on innovating various types of mechanophores with inherent reactivity (e.g. regioselectivity and stereoselectivity). However, little attention has been given to modulating their reactivity by tailoring force transmission within mechanophores. Here, we introduce a novel approach through the implementation of a cyclic pulling geometry into an anthracene‐maleimide (AM) mechanophore. This approach manipulates force transmission within the mechanophore and effectively regulates its reactivity from 0.0160 min−1 to 0.00133 min−1, achieving up to a 12‐fold change. Mechanochemical coupling analysis indicates that the split force transmission along ring chains contributes to the significant difference in mechanochemical reactivity. By leveraging the distinct force transmission pathways within cyclic and linear AM mechanophores, we covalently integrate them with a spiropyran mechanophore to design tandem mechanophore systems for hierarchical mechanochemical activation. These findings highlight the efficacy and versatility of the cyclic pulling strategy in modulating mechanophore reactivity, providing valuable insights for the design of tunable multifunctional polymer‐based materials. [ABSTRACT FROM AUTHOR]

This research explores the efficacy of integrating nonlinear single-degree-of-freedom systems in the vibration control of rod coupling systems. By interlinking two rods with a nonlinear single-degree-of-freedom system as the intermediary, the study employs the Lagrange method (LM) to forecast nonlinear vibrational behaviors. The findings, substantiated by numerical analyses, affirm the precision of LM in gauging the amplitude responses when such a nonlinear system is utilized. The nonlinear dynamics, characterized by intricate vibrational patterns, peak jumping phenomena, and the migration of resonance zones, are induced by the nonlinear single-degree-of-freedom system. By fine-tuning the system's parameters, significant alterations in the vibrational states of the rod coupling system are achievable. This suggests that the application of a nonlinear single-degree-of-freedom system is a viable strategy for modulating vibrations in rod systems. Furthermore, optimal parameterization of this system is proven to effectively dampen vibrations, showcasing its potential as a sophisticated mechanism for vibration suppression in coupled rod configurations. [ABSTRACT FROM AUTHOR]

In order to eliminate the adverse effects caused by power coupling of the isolated three‐port converter (ITPC), this paper proposes a three‐port resonant converter that uses a switch‐controlled‐capacitor (SCC) and an auxiliary inductor, which has resonant parameter compensation capability (RPC‐ITPC). The topology and operational principle of RPC‐ITPC are discussed in detail. To achieve resonant‐type power decoupling, it is usually necessary to ensure that the resonant frequency of the decoupling port resonant tank is consistent with the switching frequency, which puts high demands on the accuracy of the resonant components. To address the sensitivity of resonant‐type power decoupling to the parameters of resonant components, an SCC was adopted to solve the problem. The use of SCC enables the RPC‐ITPC to have resonant parameter compensation capability. In order to further optimize the performance of the RPC‐ITPC, a triple‐phase‐shift (TPS) modulation strategy is proposed to achieve the minimum RMS value of resonant current (MRMS‐TPSMS). Under the MRMS‐TPSMS, the switching devices of the power decoupling port have difficulty achieving ZVS turn‐on. To circumvent this problem, we realize ZVS of the decoupling port switching devices via auxiliary inductor current injection. Finally, a 1 kW experimental prototype was constructed to validate the theoretical propositions presented in this study. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Background: Suicidal persons' contacts with services present a key opportunity for suicide prevention. However, interventions by services are not always effective. A deeper understanding of suicidal service users' agency and its implications may facilitate the provision of meaningful responses to help-seeking during suicidal crises. This abductive study explores the recovery-related agency of suicide attempt survivors and the perceived role of interactions with services in facilitating or hindering it. Methods: Fourteen Finnish suicide attempt survivors were interviewed in-depth on their experiences of interacting with services during a recent suicidal episode. An operationalization of recovery-related agency as the expressed ability to take (mental or physical) action in a direction perceived as aiding recovery from suicidality (i.e., the coupling of recovery-related intentionality and power) was used to explore transcribed interviews through directed content analysis. Data were further categorized based on whether the service context was perceived as helpful or unhelpful to recovery efforts. Results: All participants expressed both agency and non-agency in relation to their recovery process. The relational context provided by services was presented as highly relevant for the achievement and sustainability of recovery-related agency as well as for participants' experience of safety in instances when agency was lacking. The results are presented as a typology of recovery-related agency in its perceived relational context, with the categories of sustained agency, strained agency, contained non-agency and uncontained non-agency. Conclusions: The concept of agency helped capture important aspects of suicidal individuals' recovery-related efforts and the role of services in facilitating or hindering them. The findings illuminate the value of viewing suicidal service users as agents of their own recovery process as well as the potential costs of ignoring this perspective in service delivery and design. [ABSTRACT FROM AUTHOR]

Due to the use of multi winding high-frequency isolation transformers in the three port isolated bidirectional DC–DC converter to achieve port isolation and power transmission, there is a power coupling problem between each port. This article proposes a Model Prediction Control (MPC) strategy to address this issue. Considering the control objectives for each port of the Triple Active Bridge (TAB) DC–DC converter, a discrete predictive model of the TAB converter is established based on phase-shifting modulation and average model. The MPC problem is solved optimally and a predictive controller is designed with control accuracy to achieve decoupling control effect between each port. And the traditional single voltage closed-loop control, diagonal matrix decoupling control, and model predictive control proposed in this paper are compared through simulation. Finally, a TAB converter experimental platform is built based on the DSP control chip TMS320F28335. The experimental results are verified the effectiveness and superiority of the proposed method, as well as its faster dynamic characteristics and power decoupling ability between each port. [ABSTRACT FROM AUTHOR]