Coupling Configuration Research Articles

A computational approach based on extended finite element method for thin porous layers in acoustic problems

AbstractThe simulation of stationary acoustic fields involving thin porous layers is addressed in the present article. Layer thickness is assumed to be relatively thin in comparison to the overall computational domain, but its non‐negligible acoustic impact must be taken into consideration in the numerical model. Within the classical finite element method (FEM), meshes are compatible at material interfaces and the element distortions needs to be avoided. These requirements usually lead to an excessively costly spatial discretization for these problems of interest, as it forces mesh refinement surrounding the thin layer. This article provides a computational approach to relax this restriction. A generalized interface model derived from the plane wave transfer matrix Method (TMM) is established for modeling thin layers. We develop variationally consistent formulations to impose the interface conditions from models of thin layers for diverse coupling configurations, in which both acoustic fluid and poro‐elastic media are taken into account. The computational domain is discretized using the extended finite element method (X‐FEM) in order to introduce strong discontinuities in elements independently of the mesh. Implementation of the proposed formulations within X‐FEM is verified to be capable of providing accurate and robust solutions. The efficiency and flexibility of the present approach for multi‐layer and complex geometry problems are demonstrated compared to classical interface‐fitted finite element models through different simulation scenarios.

Precise interface modulation cascade enables unidirectional charge transport

Maneuvering spatial photo-induced charge modulation/separation over semiconductor-based photocatalysts represents an enduring challenge in solar-powered photoredox catalysis, but suffers from sluggish charge transport kinetics, confined light absorption scope, limited active species, and rapid charge recombination rate. Herein, we conceptually demonstrate the elaborate design of all transition metal chalcogenides (TMCs)-comprising heterostructures via a facile, controllable, and precise cascade cation exchange strategy. This progressive route strategically extends the light absorption of TMCs, engenders elegant heterostructured interface, and furnishes favorable energy level alignment. The resultant TMCs heterostructures demonstrate markedly enhanced and multifarious photoactivities, owing predominantly to the robust interfacial electronic coupling and applicable energy level configuration among the building blocks, synergistically resulting in the reinforced charge transfer impetus and considerably prolonged charge lifespan. Our work would provide an emerging avenue to fine tuning of vectorial charge motion via such a judicious interface modulation strategy for solar-to-chemical energy conversion.

Which threshold do we trust? A comparison of threshold measurements in adult bone-conduction device users and normal hearing adults

ObjectivesAdvancements in prescriptive formulae for bone-conduction hearing devices (BCDs) have highlighted the importance of measuring in-situ bone-conduction hearing thresholds. In-situ measurements are performed within the BCD manufacturer's software, using the patient's BCD as a transducer. While in-situ testing is a different approach than standard diagnostic bone-conduction testing, both approaches are in fact measuring the same inner ear hearing. Despite this, each approach may result in different thresholds for the same individual. This study aimed to answer the following question: In adults with normal hearing and adults who currently wear a bone-conduction device, are there differences and, if so, how large are these differences when thresholds are measured using different approaches? DesignBone-conduction hearing thresholds were measured for a group 32 normal hearing participants and a group 15 percutaneous BCD users. The normal hearing participants were tested in two conditions: (1) in-situ, with a BCD worn on a soft-band and (2) with the B71 bone-conduction diagnostic transducer. The BCD users were tested in these two conditions and (3) in-situ with a BCD attached to their abutment. In-situ hearing thresholds were measured with BCDs from two manufacturers. The mean intra-subject differences between these conditions were calculated. ResultsFor the normal hearing participants, BCD softband thresholds were poorer than the thresholds obtained with the diagnostic transducer across all tested frequencies. The average differences between the BCD softband thresholds and the diagnostic transducer were particularly large in the high frequencies (13 to 35 dB from 3 to 6 kHz). Similar differences were observed for the BCD user participants when comparing their BCD softband thresholds to the diagnostic transducer thresholds. The in-situ percutaneous thresholds were on average better than the diagnostic bone-conduction thresholds, although the differences were not statistically significant. Skin attenuation, calibration differences, and BCD characteristics were contributing factors to these differences. ConclusionsThe intra-subject differences measured in this study confirmed that using different bone-conduction transducers results in the measurement (i.e., recording) of different hearing threshold levels. These results support the necessity for a measurement tool able to measure audibility at threshold independent of the various coupling configurations used in bone-conduction amplification. An effective measurement tool would be required to take into account, or bypass, the factors contributing to the differences measured in this study. Until such a tool is commercially available, clinicians will continue to face uncertainty when fitting and attempting to assess the audibility of passive transcutaneous BCDs.

Evaluating individual heating alternatives in integrated energy system by employing energy and exergy analysis

With the aim to meet customers diverse energy needs by an economical and ecological means, integrated energy system has become a popular choice. Amongst various integrated energy system coupling configurations, individual heating infrastructure entails painstaking attention due to rapid expansion. Individual heating network plays a massive role in carbonizing the atmosphere as traditionally individual heating demands are fulfilled by fossil fuel-fired (natural gas and coal) boilers. Recently, trend is heading towards the integration of energy efficient technologies like micro combined heat and power and heat pumps to replace fossil fuel boilers. However, individual heating performance evaluation is generally investigated by energy analysis that employs only the first law of thermodynamics, thereby exergy analysis assessment and its comparison with energy analysis become noteworthy to measure actual performance. In this work, energy and exergy analysis of the individual heating network of China for the year 2030 is performed under the framework of both laws of thermodynamics. The proposed work includes various technological options like Hydrogen fired micro combined heat and power, natural gas fired micro combined heat and power and heat pumps to replace the fossil fuel boilers intending to attain an economically viable and carbon-free environment. At first, energy and exergy efficiencies of the aforementioned heat producing components are computed and afterwards EnergyPLAN technical simulation strategy is employed to evaluate performance in terms of costs, CO2 emissions and primary energy supply. Subsequently, a comparison of both analysis is provided in order to present the difference between the two analysis which substantiates that exergy analysis provides inferior results than energy analysis as depicted in case 3 where heat pumps inclusion appears to be the most decarbonized alternative for energy analysis but corroborates vice versa for exergy analysis. However, exergy analysis complements the energy analysis that helps evaluating the actual performance of system in relation to climate change mitigation and cost-effectiveness.

Programmable Gilbert Damping in Py /Cu/Fe - Co - Tb Structures with Dynamic Interlayer Coupling

Magnetodynamics of magnetic nanolayers is central to the emerging research field of magnonics. Here, we demonstrate an effective tuning of the dynamic properties of permalloy (Py, response layer) thin films, by capping with $\mathrm{Cu}/\mathrm{Fe}$-$\mathrm{Co}$-$\mathrm{Tb}$ (spin-sink layer) layers with adjustable interlayer coupling and magnetic configurations. The strategy enables a remarkably enhanced Gilbert damping of the response layer, by about 10 times; this enhancement is higher than most of the results reported so far. More importantly, dynamic damping is programmable between the two opposite configurations (parallel vs antiparallel) in Py and $\mathrm{Fe}$-$\mathrm{Co}$-$\mathrm{Tb}$ and remains intact even in the form of nano- and microdevices. The interlayer coupling between Py and $\mathrm{Fe}$-$\mathrm{Co}$-$\mathrm{Tb}$ is systematically studied by changing the thickness of the $\mathrm{Cu}$ spacer. It is demonstrated that the dynamic interlayer coupling between ferromagnetic layers plays the key role in increased damping. Our work provides a feasible route towards reconfigurable magnonic devices, especially for logic and high-speed computing.

How Does Air‐Sea Wave Interaction Affect Tropical Cyclone Intensity? An Atmosphere‐Wave‐Ocean Coupled Model Study Based on Super Typhoon Mangkhut (2018)

AbstractCapturing TC intensity change remains a great challenge for most state‐of‐the‐art operational forecasting systems. Recent studies found TC intensity forecasts are sensitive to three‐dimensional ocean dynamics and air‐sea interface processes beneath extreme winds. By performing a series of numerical simulations based on hierarchical atmosphere‐wave‐ocean (AWO) coupling configurations, we showed how atmosphere‐ocean and atmosphere‐sea wave coupling can affect the intensity of super typhoon Mangkhut (2018). The AWO coupled model can simulate TC‐related strong winds, oceanic cold wake, and wind waves with high fidelity. With atmosphere‐ocean (AO) coupling implemented, the simulated maximum surface wind speed is reduced by 7 m s−1 compared to the atmosphere‐only run, due to TC‐induced oceanic cold wakes in the former experiment. In the fully coupled AWO simulations, the wind speed deficit can be completely compensated by the wave‐air coupling effect. Further analyses showed that, in the AWO experiment, two mechanisms contribute to the improvement of TC intensity. First, in the high wind scenario (>28 m s−1), the surface drag coefficient reaches an asymptotic level, assisting extreme wind speed to be maintained within the eyewall. Second, the wind speed distribution is modulated and becomes broader; higher wind within the TC area helps to offset the negative effect due to leveling off of the heat exchange coefficient as wind speed increases. Overall, the simulated TC in the AWO run can extract 8–9% more total heat energy from the ocean to maintain its strength, compared to that from the AO experiment.

Detoxification and selective separation of Cr(VI) and As(III) in wastewater based on interfacial coupling in BiOBr with {110} facet under visible-light irradiation

Layered structural BiOBr with {110} facet exposure is a promising functional material for highly selective adsorption and separation of heavy metal ions in water purification. In this study, the distinct adsorption behaviors of As(III), As(V), and Cr(VI) on {110} facet were theoretically and experimentally investigated. The results suggested that uncharged As(III) was dominantly adsorbed on the [Bi2O2]2+ surface replacing the hydroxyl group, whereas Cr(VI) and As(V) oxyanions preferentially intercalated on {110} facet by exchange with Br- ions between the layers. Moreover, due to interfacial coupling configuration ([BiO-CrO4-OBi]-O-As(OH)2) between the surface and interlayer on {110} facet, the synergic removal of Cr(VI) and As(III) could be accelerated under photoexcitation to induce a direct electron transfer from surface AsIII to interlayer CrVI, forming AsV and CrIII. Subsequently, approximately 69.3% of Cr(III) and 98.6% of As(V) were readily desorbed in acidic conditions and a high concentration of Br- solution, respectively, to achieve simultaneous detoxification and selective separation.

Localized surface plasmon resonance (LSPR) of coupled metal nanospheres in longitudinal, transverse and three-dimensional coupling configurations

localized surface plasmon resonance of metal nanoparticles is highly regarded by researchers due to its special applications. In the paper, the spectral response of the coupled metal nanospheres located in a silica fiber is explored using the boundary element method as a fast and appropriate numerical method for phenomena related to scattered waves. Three different coupling configurations including longitudinal, transverse, and three-dimensional coupling is simulated and investigated. The results declare that the coupling distance and the angle between nanoparticles relative position vector and direction of light propagation, in addition to the radii of the metal nanoparticles and the refractive index of the environment, can affect the shape of scattering cross-sectional spectrum and also the position and linewidth of the resonance peaks. Furthermore, the effects of coupling in the LSPR spectrum of longitudinal coupled structures are observed even up to long coupling distances (about 300 nm for gold nanospheres), while these effects are negligible in the transverse coupled structures in the studied range. Also, a threshold can be defined for effective coupling distance, which determines whether the coupling effects are significant or not. The results show that this threshold value is independent of the radius of metal spherical nanoparticles. Finally, the results prove that the dominant coupling in the three-dimensional structures is the longitudinal coupling that controls the threshold coupling value of the structure and it is 300 nm for structures based on gold spherical nanoparticles. This threshold value is an important quantity for better decisions about LSPR-based applications.

Experimental analysis and 1D simulation of an advanced hybrid boosting system for automotive applications in transient operation

Due to the increasingly restrictive limits of pollutant emissions, electrification of automotive engines is now mandatory. For this reason, adopting hybrid boosting systems to improve brake specific fuel consumption and time-to-boost is becoming common practice. In this paper an advanced turbocharging system is analyzed, consisting in an electrically assisted radial compressor and a traditional turbocharger. As a first step, the steady-state performance of each component was measured at the University of Genoa test rig. Subsequently another experimental campaign was carried out to evaluate the transient response of the entire turbocharging system. Two different layouts were compared: upstream and downstream. In the upstream configuration the electrically assisted compressor was placed in front of the traditional turbocharger, in the downstream configuration the e-compressor was positioned after the traditional turbocharger. The two different coupling configurations, upstream and downstream, were then modeled in 1-D simulation software following the dimensions and characteristics of the experimental line from which the exploited data originates. The models were first validated by emulating the steady-state condition and subsequently the transient response was simulated and analyzed. Secondly, the transient response of the two layouts was compared, removing the constraints imposed by the experimental activity. The practical significance of the results is outlined, with reference to the transient response of the turbocharger. The adoption of the boosting system presented here allows a fast and stable transient response. Moreover, a reduction in the engine back pressure could be achieved through an optimization of the boosting system-engine matching calculation.

Relation between scattering matrix topological invariants and conductance in Floquet Majorana systems

We analyze the conductance of a one-dimensional topological superconductor periodically driven to host Floquet Majorana zero-modes for different configurations of coupling to external leads. We compare the conductance of constantly coupled leads, as in standard transport experiments, with the stroboscopic conductance of pulsed coupling to leads used to identify a scattering matrix topological index for periodically driven systems. We find that the sum of DC conductance at voltages multiples of the driving frequency is quantitatively close to the stroboscopic conductance at all voltage biases. This is consistent with previous work which indicated that the summed conductance at zero/pi resonance is quantized. We quantify the difference between the two in terms of the width of their respective resonances and analyze that difference for two different stroboscopic driving protocols of the Kitaev chain. While the quantitative differences are protocol-dependent, we find that generically the discrepancy is larger when the zero mode weight at the end of the chain depends strongly on the offset time between the driving cycle and the pulsed coupling period.

Entanglement instability in the interaction of two qubits with a common non-Markovian environment

In this work we study the steady state entanglement between two qubits interacting asymetrically with a common non-Markovian environment. Depending on the initial two-qubit state, the asymmetry in the couplings between each qubit and the non-Markovian environment may lead to enhanced entanglement in the steady state of the system, measured in terms of the two-qubit concurrence. Our results indicate that, if a qubit-qubit interaction is also present, the two-qubit steady state concurrence is always favored by the symmetric or anti-symmetric coupling configuration. Although finite, the steady concurrence is predicted to be highly unstable in this regime as long as the interaction between the two qubits is larger than the couplings between each qubit and the non-Markovian reservoir.

Study of optical reflectors for a 100ps coincidence time resolution TOF-PET detector design

Positron Emission Tomography (PET) reconstructed image signal-to-noise ratio (SNR) can be improved by including the 511 keV photon pair coincidence time-of-flight (TOF) information. The degree of SNR improvement from this TOF capability depends on the coincidence time resolution (CTR) of the PET system, which is essentially the variation in photon arrival time differences over all coincident photon pairs detected for a point positron source placed at the system center. The CTR is determined by several factors including the intrinsic properties of the scintillation crystals and photodetectors, crystal-to-photodetector coupling configurations, reflective materials, and the electronic readout configuration scheme. The goal of the present work is to build a novel TOF-PET system with 100 picoseconds (ps) CTR, which provides an additional factor of 1.5–2.0 improvement in reconstructed image SNR compared to state-of-the-art TOF-PET systems which achieve 225–400 ps CTR. A critical parameter to understand is the optical reflector’s influence on scintillation light collection and transit time variations to the photodetector. To study the effects of the reflector covering the scintillation crystal element on CTR, we have tested the performance of four different reflector materials: Enhanced Specular Reflector (ESR) –coupled with air or optical grease to the scintillator; Teflon tape; BaSO4 paint alone or mixed with epoxy; and TiO2 paint. For the experimental set-up, we made use of 3 × 3 × 10 mm3 fast-LGSO:Ce scintillation crystal elements coupled to an array of silicon photomultipliers (SiPMs) using a novel ‘side-readout’ configuration that has proven to have lower variations in scintillation light collection efficiency and transit time to the photodetector. Results: show CTR values of 102.0 ± 0.8, 100.2 ± 1.2, 97.3 ± 1.8 and 95.0 ± 1.0 ps full-width-half-maximum (FWHM) with non-calibrated energy resolutions of 10.2 ± 1.8, 9.9 ± 1.2, 7.9 ± 1.2, and 8.6 ± 1.7% FWHM for the Teflon, ESR (without grease), BaSO4 (without epoxy) and TiO2 paint treatments, respectively.

Investigating the value of spatiotemporal resolutions and feedback loops in water-energy nexus modeling

Modeling the interactions between water and energy is crucial to managing holistically these resources. Here, we simulate water allocations and energy dispatch in the metropolitan region of Phoenix, Arizona in 2008–2017 using the WEAP and LEAP models under different spatiotemporal resolutions and coupling configurations. We find that increasing the temporal resolution from annual to monthly allows capturing seasonal demands, which improves the simulation of water allocations from supply sources to all demand nodes; the simulation of energy fluxes is instead less sensitive to the model time step. Representing the domain with higher spatial granularity enhances the ability to model the correct water portfolio of the power plants. Finally, coupling the models to capture two-way feedbacks between water and energy systems improves the simulations of electricity generation and, in turn, of water fluxes. While related to Phoenix, our findings provide useful insights to improve water-energy nexus modeling at other sites.

Asymmetrical dynamics of epidemic propagation and awareness diffusion in multiplex networks

To better explore asymmetrical interaction between epidemic spreading and awareness diffusion in multiplex networks, we distinguish susceptibility and infectivity between aware and unaware individuals, relax the degree of immunization, and take into account three types of generation mechanisms of individual awareness. We use the probability trees to depict the transitions between distinct states for nodes and then write the evolution equation of each state by means of the microscopic Markovian chain approach (MMCA). Based on the MMCA, we theoretically analyze the possible steady states and calculate the critical threshold of epidemics, related to the structure of epidemic networks, the awareness diffusion, and their coupling configuration. The achieved analytical results of the mean-field approach are consistent with those of the numerical Monte Carlo simulations. Through the theoretical analysis and numerical simulations, we find that global awareness can reduce the final scale of infection when the regulatory factor of the global awareness ratio is less than the average degree of the epidemic network but it cannot alter the onset of epidemics. Furthermore, the introduction of self-awareness originating from infected individuals not only reduces the epidemic prevalence but also raises the epidemic threshold, which tells us that it is crucial to enhance the early warning of symptomatic individuals during pandemic outbreaks. These results give us a more comprehensive and deep understanding of the complicated interaction between epidemic transmission and awareness diffusion and also provide some practical and effective recommendations for the prevention and control of epidemics.

Experimental Coupling of TOPMODEL with the National Water Model: Effects of Coupling Interface Complexity on Model Performance

AbstractThe study had two objectives; (1) Substitute National Water Model’s (NWM) runoff calculation with a conceptual hydrologic model (TOPography‐based hydrological MODEL [TOPMODEL]) to simplify the model structure and resolve potential drawbacks of applying NWM in headwater catchments. (2) Investigate how varying the coupling interface (location of coupling, type of fluxes used, modification of sub‐models) affects model behavior of when one‐way coupling the NWM’s land surface model (LSM; Noah‐Multi Parameterization) with TOPMODEL using six different scenarios. The one‐way coupled model outperformed NWM and noncoupled TOPMODEL. The coupling option limiting reliance on LSM’s surface and subsurface water fluxes by constraining them within the TOPMODEL structure was the most successful. Performance declined when coupling configurations relied more on LSM calculated fluxes to override TOPMODEL internal processes. Varying the coupling interface brought unexpected changes in TOPMODEL’s parameter sensitivity and water budget even while the statistical score remained similar. The coupling interface represents a source of structural uncertainty that could be identified through conventional evaluation of performance, uncertainty, and sensitivity due to the simple structure of our one‐way coupling design. The study shows that the benefits of combining the strengths of land surface and conceptual hydrological models, while recognizing that structural uncertainty from coupling design needs to be acknowledged.

Detection of necrotrophic DNA marker of anthracnose causing Colletotrichum gloeosporioides fungi in harvested produce using surface plasmon resonance

Agriculture and food crops monitoring is extremely important for securing the food supply chain to human society. Here, we developed a highly specific detection method for monitoring pathogenic fungus Colletotrichum gloeosporioides using necrotrophic DNA biomarker as the recognition element and surface plasmon resonance (SPR) as transducing mechanism in the prism coupling configuration. The sensor shows its response for a wide range of concentrations from pM to μM of target DNA sequence using a complementary DNA probe immobilized on the sensor surface, which could detect concentrations as low as 7 pM. The detection limit is found to be comparable with conventional molecular-based detection platforms, achieved due to optimized spectral SPR bimetallic substrate with subpixel resolution obtained by post processing. The response time of the sensor for detection is less than 30 min at room temperature. The quick detection scheme of the sensor may facilitate the screening of a large number of samples acquired for the sorting of harvested produce. This sensor is fast, reliable, cost-effective, and can be miniaturized for portability for the screening of real samples (mRNA) in the field and packaging house.

Matrix projective synchronization for a class of discrete-time complex networks with commonality via controlling the crucial node

This article proposes two control strategies to realize matrix projective synchronization (MPS) for a class of discrete-time complex dynamical networks (DTCDNs). It is worth pointing out that our network model is composed of nodes with different state dimensions and its outer coupling configuration matrix can be asymmetric. In addition, since a small percentage of nodes that play more important role than others usually exist in a network, thus, one important node, which is named as crucial node in this paper, is taken into account in our network model. Besides, the commonality between each node and the crucial node is also precisely expressed. Further, based on the crucial node and the commonality and associated with the Lyapunov stability theory, two control strategies are addressed to realize the exponential matrix projective synchronization (EMPS) and asymptotic matrix projective synchronization (AMPS), respectively. It should be stressed that only the crucial node is controlled and only the state of the crucial node is applied to design the EMPS and AMPS controllers. This is promising to reduce the control cost as much as possible and to improve the feasibility of our MPS strategies. The effectiveness and feasibility of our MPS schemes are rigorously proved in theory as well as verified by two numerical examples.

An Overview of Artificial Olfaction Systems with a Focus on Surface Plasmon Resonance for the Analysis of Volatile Organic Compounds.

The last three decades have witnessed an increasing demand for novel analytical tools for the analysis of gases including odorants and volatile organic compounds (VOCs) in various domains. Traditional techniques such as gas chromatography coupled with mass spectrometry, although very efficient, present several drawbacks. Such a context has incited the research and industrial communities to work on the development of alternative technologies such as artificial olfaction systems, including gas sensors, olfactory biosensors and electronic noses (eNs). A wide variety of these systems have been designed using chemiresistive, electrochemical, acoustic or optical transducers. Among optical transduction systems, surface plasmon resonance (SPR) has been extensively studied thanks to its attractive features (high sensitivity, label free, real-time measurements). In this paper, we present an overview of the advances in the development of artificial olfaction systems with a focus on their development based on propagating SPR with different coupling configurations, including prism coupler, wave guide, and grating.

Evaluating the coupling efficiency of OAM beams into ring-core optical fibers

In optical communications, space-division multiplexing is a promising strategy to augment the fiber network capacity. It relies on modern fiber designs that support the propagation of multiple spatial modes. One of these fibers, the ring-core fiber (RCF), is able to propagate modes that carry orbital angular momentum (OAM), and has been shown to enhance not only classical but also quantum communication systems. Typically, the RCF spatial modes are used as orthogonal transmission channels for data streams that are coupled into the fiber using different free space beams. Free space beams commonly used are Laguerre-Gaussian (LG) and perfect vortex (PV) beams. Here, we study the optimal conditions to multiplex information into ring-core fibers in this scheme. We study the beam coupling efficiency using the overlap between free space beams and RCF bound beams and determine which are the most relevant LG beams to be considered and how their coupling efficiency can be maximized by properly adjusting the beam width with respect to the fiber parameters. Our results show that the coupling efficiency depends upon the OAM value and that this can limit the achievable transmission rates in SDM systems. In this regard, we find optimal coupling configurations for LG beams based on the RCF fiber and beam parameters. Further, we study the PV beam that allows for nearly perfect coupling efficiencies for all spatial modes supported by these fibers. PV beams present higher coupling efficiencies than LG beams and negligible dependence on the OAM value, thus offering an attractive solution to multiplex high counts of OAM channels from free space into a ring-core fiber using a single coupling configuration.

Accelerated Adaptive Fuzzy Optimal Control of Three Coupled Fractional-Order Chaotic Electromechanical Transducers

In this article, we investigate the issue of the accelerated adaptive fuzzy optimal control of three coupled fractional-order chaotic electromechanical transducers. A small network where every transducer has the nearest-neighbor coupling configuration is used to form the coupled fractional-order chaotic electromechanical transducers. The mathematical model of the coupled electromechanical transducers with nearest-neighbors is established and the dynamical analysis reveals that its behaviors are very sensitive to external excitation and fractional order. In the controller design, the recurrent nonsingleton type-2 sequential fuzzy neural network (RNT2SFNN) with the transformation is designed to estimate unknown functions of dynamics system in the feedforward fuzzy controller, and it is constructed to approximate the critic value and actor control functions by using policy iteration (PI) in the optimal feedback controller. Meanwhile, the speed functions are employed to achieve accelerated convergence within a pregiven finite time and a tracking differentiator is used to solve the explosion of terms associated with traditional backstepping. The whole control strategy consists of a feedforward controller integrating with the RNT2SFNN, tracking differentiator, and speed function in the framework of the backstepping control and a feedback controller fusing with the RNT2SFNN and PI under an actor/critic structure to solve the Hamilton–Jacobi–Bellman equation. The proposed scheme not only guarantees the boundness of all signals and realizes the chaos suppression, synchronization, and accelerated convergence, but also minimizes the cost function. Simulations demonstrate and validate the effectiveness of the proposed scheme.