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In this paper, we have investigated red light (∼ 660 nm) and magnetic field dependence of impedance across (100 − x)% ZnO(zinc oxide)– x % rGO(reduced graphene oxide)/La 0.7 Sr 0.3 MnO 3 (LSMO)/ITO (x =0,0.6,0.8,100) heterostructure devices. Field-induced scattering due to the spin filter effect and spin polarized tunneling (SPT) have been extracted from the zinc oxide–reduced graphene oxide nanocomposite/LSMO space charge region (ZnO–rGO/LSMO SCR) and the LSMO active region of the devices, respectively. Higher SPT leads to higher LSMO SCR scattering across the devices. Devices with higher rGO contents could not be fitted with two RC circuits as resistance values because the two phenomena are incomparable with each other. Light-induced scattering has been observed at the ZnO–rGO nanocomposite active region and ZnO–rGO/LSMO SCR of the devices. For composite devices with x =0.8 and 0.6, higher photocarrier generation at ZnO–rGO nanocomposite active layer leads to enhanced scattering at LSMO SCR with light illumination. Light-dependent scattering at both regions, however, follows almost same decreasing trend for bare devices with x =0, 100. The decreasing trend of light-dependent scattering for ZnO/LSMO/ITO and rGO/LSMO/ITO bare devices suddenly gets reversed and, eventually, follows an increasing trend at magnetic field ambiance of 0.5 and 1 kOe, respectively. The LSMO SCRs of the bare devices got enhanced with the field, leading to a light-dependent response similar to composite devices at the higher field. [ABSTRACT FROM AUTHOR]

A new passive RC analog of a coupled double tuned circuit, as is commonly used in broad-band RF amplifiers, is presented in this paper. It consists of a cascade of bandstop Wien network and a bandpass parallel-T network. A by-product of this study is that by inverting this circuit, we get a wide-band rejection circuit. By interchanging the order of the cascade, we get different frequency responses. All of these circuits are amenable for IC fabrication, and have several advantages over the existing active RC simulation circuits for the purpose. [ABSTRACT FROM AUTHOR]

A method based on strong tracking unscented Kalman filter with multiple suboptimal fading factors (MSTUKF) was proposed to accurately estimate the state of charge (SOC) of power batteries of electric vehicles online. Taking a certain lithium-ion battery as the research object, a second-order RC equivalent circuit model of the battery was established based on its external characteristics and related mechanism. Then the recursive least squares method with forgetting factor was adopted to identify the model parameters, and the MSTUKF nonlinear state space equation of the battery was established according to the equivalent circuit model. Finally, the SOC estimation algorithm was verified by simulation experiments under ECE15 and UDDS conditions. The results show that the error of MSTUKF in SOC estimation of lithium-ion battery is kept within 1.5%, so this method can estimate battery SOC accurately. [ABSTRACT FROM AUTHOR]

Droplet-based electricity generators (DEGs) have garnered significant interest due to their straightforward metal substrate/dielectric/metal electrode configurations and their capacity to produce instantaneous high power. This study investigates the influence of droplet conductivity and drop conditions on circuit parameters through an analysis of I–V characteristics under varying load resistance conditions. The results reveal that alterations in droplet resistance and polytetrafluoroethylene (PTFE) charge density due to varying droplet dynamics play a pivotal role in shaping DEG output. The charged state of PTFE on DEG was found to differ with the expansion and contraction of the droplets. [ABSTRACT FROM AUTHOR]

Background: The extremely fast delivery of doses with ultra high dose rate (UHDR) beams necessitates the investigation of novel approaches for real‐time dosimetry and beam monitoring. This aspect is fundamental in the perspective of the clinical application of FLASH radiotherapy (FLASH‐RT), as conventional dosimeters tend to saturate at such extreme dose rates. Purpose: This study aims to experimentally characterize newly developed silicon carbide (SiC) detectors of various active volumes at UHDRs and systematically assesses their response to establish their suitability for dosimetry in FLASH‐RT. Methods: SiC PiN junction detectors, recently realized and provided by STLab company, with different active areas (ranging from 4.5 to 10 mm2) and thicknesses (10–20 µm), were irradiated using 9 MeV UHDR pulsed electron beams accelerated by the ElectronFLASH linac at the Centro Pisano for FLASH Radiotherapy (CPFR). The linearity of the SiC response as a function of the delivered dose per pulse (DPP), which in turn corresponds to a specific instantaneous dose rate, was studied under various experimental conditions by measuring the produced charge within the SiC active layer with an electrometer. Due to the extremely high peak currents, an external customized electronic RC circuit was built and used in conjunction with the electrometer to avoid saturation. Results: The study revealed a linear response for the different SiC detectors employed up to 21 Gy/pulse for SiC detectors with 4.5 mm2/10 µm active area and thickness. These values correspond to a maximum instantaneous dose rate of 5.5 MGy/s and are indicative of the maximum achievable monitored DPP and instantaneous dose rate of the linac used during the measurements. Conclusions: The results clearly demonstrate that the developed devices exhibit a dose‐rate independent response even under extreme instantaneous dose rates and dose per pulse values. A systematic study of the SiC response was also performed as a function of the applied voltage bias, demonstrating the reliability of these dosimeters with UHDR also without any applied voltage. This demonstrates the great potential of SiC detectors for accurate dosimetry in the context of FLASH‐RT. [ABSTRACT FROM AUTHOR]

Accurate estimation of State-of-Charge (SoC) is essential for ensuring the safe and efficient operation of electric vehicles (EVs). Currently, second-order RC equivalent circuit models do not account for the influence of battery charging and discharging states on battery parameters. Additionally, offline parameter identification becomes inaccurate as the battery ages. Online identification requires real-time parameter updates during the SoC estimation process, which increases the computational complexity and reduces the computational efficiency of real vehicle Battery Management System (BMS) chips. To address these issues, this paper proposes a SoC estimation method that combines online and offline identification based on an optimized second-order RC equivalent circuit model, which distinguishes it from existing methods in the field. On the basis of the traditional second-order RC model, the Ohmic resistance (R0), polarization resistance (R1), polarization capacitance (C1), diffusion resistance (R2), and diffusion capacitance (C2) during the charging and discharging processes are discussed separately. R0, which does not change frequently, is identified offline, while R1, R2, C1, and C2, which dynamically change with time and current, are identified online. To thoroughly verify the feasibility of the proposed method, we construct an SoC estimation test bench, which allows us to adjust the battery's surface temperature in real time using a temperature control chamber. Experimental validation under Federal Urban Driving Schedule (FUDS) (−10 °C to 45 °C, 80% battery capacity) and Dynamic Stress Test (DST) (−10 °C to 45 °C, 8% battery capacity) conditions demonstrate that our method improves SoC estimation accuracy by 16.28% under FUDS and 28.2% under DST compared to the improved GRU-based transfer learning method, while maintaining system SoC estimation efficiency. [ABSTRACT FROM AUTHOR]

A direct bidirectional current discharge path between the input/output (I/O) and ground (GND) is essential for the robust protection of charging device models (CDM) in the tightly constrained design parameters of advanced low-voltage (LV) processes. Dual-direction silicon controlled rectifiers (DDSCRs) serve as ESD protection devices with high efficiency unit area discharge, enabling bidirectional electrostatic protection. However, the high trigger voltage of conventional DDSCR makes it unsuitable for ASICs used for the preamplification of biomedical signals, which only operate at low supply voltage. To address this issue, a self-biased triggered DDSCR (STDDSCR) structure is proposed to further reduce the trigger voltage. When the ESD pulse comes, the external RC trigger circuit controls the PMOS turn-on by self-bias, and the current release path is opened in advance to reduce the trigger voltage. As the ESD pulse voltage increases, the SCR loop opens to establish positive feedback and drain the amplified current. Additionally, the junction capacitance is decreased through high-resistance epitaxy and low-concentration P-well injection to further lower the trigger voltage. The simulation results of LTspice and TCAD respectively demonstrate that ESD devices can clamp transient high voltages earlier, with low parasitic capacitance and leakage current suitable for ESD protection of high-speed ports up to 1.5 V under normal operating conditions. [ABSTRACT FROM AUTHOR]

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

A second-order RC equivalent circuit model was established to accurately estimate the state of charge (SOC) of power lithium battery. The model parameters were identified online using the recursive gradient correction (RGC) algorithm, enhancing the real-time performance of parameter identification. Building on the unscented Kalman filter (UKF) algorithm, a multi-innovation unscented Kalman filter (MIUKF) algorithm was proposed by incorporating the multi-innovation identification theory. This approach overcomes the impact of ignoring historical errors in traditional Kalman filter algorithms on estimation accuracy, thereby accelerating the algorithm's convergence to the true value and improving its accuracy and stability. The algorithm was validated under various operating conditions. The results indicate that, compared to the UKF algorithm, the MIUKF algorithm exhibits superior performance in estimation accuracy and anti-interference capability, enabling precise SOC estimation for lithium batteries in vehicles. [ABSTRACT FROM AUTHOR]

A vanadium redox flow battery (VRFB) is an intermittent energy storage device that is primarily used to store and manage energy produced using sustainable sources like solar and wind. In this work, we study the modeling and operation of a single-cell VRFB whose active cell area is 25 cm 2 . Initially, we operate the cell at multiple flow rates by varying the current densities to study the behavior of the cell at different flow rates. Based on the observations from this experimental study, a suitable flow rate is selected such that the power density of the cell is maximized. In order to accurately represent the dynamic behavior of the VRFB, an electrical equivalent circuit model (ECM) is introduced from existing models documented in the literature based on simplicity and accuracy based on the RMS value of the error in the output voltage. Additionally, the pulse charge–discharge test was conducted on the VRFB under the specified operating flow rate. The data obtained from this test were utilized to estimate the parameters of the dynamical equivalent circuit model. In our study, we have proposed a modified state of charge (SOC) equation considering the self-discharge current loss through a parallel resistor while identifying the SOC–OCV relationship. Analysis of VRFB charge–discharge data is employed to validate the ECM, and the accuracy of the model is determined based on RMSE between the terminal voltage predicted by the model and the actual experimental setup. The resulting RMSE is found to be 19.4 mV, describing the model accuracy of 98.73%. [ABSTRACT FROM AUTHOR]

Summary In this paper, computational analysis of a Caputo fractional variable‐order system with inductor‐capacitor (LC) and resistor‐capacitor (RC) electrical circuit models is presented. The existence and uniqueness of solutions to the given problem are determined using Schaefer's fixed point theorem and the Banach contraction principle, respectively. The proposed problem's computational consequences are addressed and analyzed using modified Euler and Runge–Kutta fourth‐order techniques. Furthermore, the suggested model compares several orders, including integer, fractional, and variable orders. To demonstrate the utility of the proposed approach, computational simulations are carried out on LC and RC circuit models of various orders. Furthermore, a comparative analysis with previous investigations has been carried. For the given problem, the numerical solution results in high‐precision approximations. [ABSTRACT FROM AUTHOR]

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

This paper focuses on the analysis and control strategy of a four-switch boost-buck AC/DC converter utilized in power factor correction applications with a wide output voltage range. Given the increasing importance of electric vehicles and the need for high reliability, this study addresses the internal dynamic stability problem that can arise in the converter system. The analysis begins with a thorough examination of the system's min-phase characteristic. Despite this, internal dynamic stability issues persist, requiring a solution to ensure a higher power factor and reliability. To address this challenge, this paper proposes the utilization of a damping RC circuit instead of reducing the loop gain bandwidth. To demonstrate the internal dynamic behavior of the converter, small-signal modeling is employed. This modeling highlights the importance of mitigating internal dynamic instability to achieve the desired power factor and reliability. This study emphasizes the significance of proper analysis and control strategies for boost-buck AC/DC converters in power factor correction applications. By addressing internal dynamic stability using a damping RC circuit, the converter can achieve a higher power factor and enhanced reliability, ultimately contributing to the development of more efficient and dependable EV systems. Finally, the feasibility of the proposed analysis and control strategy is confirmed through comprehensive simulations. The simulation results validate the effectiveness of using a damping RC circuit to address the internal dynamic stability problem, leading to an improved power factor and enhanced reliability. [ABSTRACT FROM AUTHOR]

The battery needs to provide a large amount of power in a short time under the condition of a high pulse rate. Real time and accurate State of Charge (SOC) prediction can help the battery management system understand the current status of the battery better, optimize the battery charging and discharging strategy, and improve the efficiency of the battery. In order to prolong battery life and enhance battery safety, a real-time prediction algorithm for SOC of the power battery under a high pulse rate was proposed. The second order RC equivalent circuit is used to establish the model of the battery. The equivalent circuit model of the battery is designed online using the recursive least squares algorithm, and the time-varying parameter model of the battery is established. Its output value is used as the input to the gating recurrent cell neural network, and the neural network is used to output the predicted SOC value. The SOC prediction result is used as the observation vector of the adaptive extended Kalman filter algorithm to obtain the final real-time prediction result of lithium ion power battery SOC. The experimental results show that the parameters identified by the research algorithm for lithium-ion power batteries are as follows: the fluctuation range of ohmic internal resistance is 0.05–0.40 Ω, and the fluctuation range of electrochemical polarization is 0–4.5 F. The terminal voltage values collected by the research algorithm have higher accuracy, with the error being always less than 0.03 V. Moreover, the algorithm can effectively predict the SOC of lithium-ion power batteries in real time, with a maximum average absolute error of about 2%. [ABSTRACT FROM AUTHOR]

A millimeter-wave (mmWave) gallium nitride (GaN) high-power amplifier (HPA) monolithic microwave-integrated circuit (MMIC) was implemented, considering a source via effect. In this paper, we introduce guidelines for designing GaN HPA MMICs, from device sizing to meeting high-power specifications, power matching considering source via effects, schematic design of three-stage amplifier structures, and electromagnetic (EM) simulation. Based on the results of load pull simulation and small-signal maximum stable gain (MSG) simulation, the GaN high-electron-mobility transistor (HEMT) size was selected to be 8 × 70 μm. However, since the source via model provided by the foundry was significantly different from the EM results, it was necessary to readjust the power matching considering this. Additionally, when selecting the source via size, the larger the size, the easier the matching, but since the layout of the peripheral bias circuit is not possible, a compromise was required considering the actual layout. To prevent in-band oscillation, an RC parallel circuit was added to the input matching circuit, and low-frequency oscillation was solved by adding a gate resistor on the PCB module. The proposed PA was fabricated with a commercial 0.1 μm GaN HEMT MMIC process. It exhibited 38.56 to 39.71 dBm output power (Pout), 14.2 to 16.7 dB linear gain, and 14.1% to 18.2% power-added efficiency (PAE) in the upper Ka band. The fabricated GaN power amplifier MMIC shows competitive Pout in the upper Ka band above 33 GHz. [ABSTRACT FROM AUTHOR]

Metasurface devices have demonstrated powerful electromagnetic wave manipulation capabilities. By adjusting the shape and size parameters of the metasurface microstructure, we can control the resonance between spatial electromagnetic waves and the metasurface, which will trigger wave scattering at a specific frequency. By utilizing these characteristics, we design a metasurface device with a bandpass filtering function and a unit cell of the metasurface consisting of a double-layer pinwheel-shaped metal structure and high resistance silicon substrate (forming metal–silicon–metal configuration). A bandpass filter operating in the terahertz band has been implemented, which achieves a 36 GHz filtering bandwidth when the transmission amplitude decreases by 3 dB and remains effective in a wave incidence angle of 20°. This work uses an equivalent RC resonance circuit to explain the formation of bandpass filtering. In addition, the photosensitive properties of silicon enable the filtering function of the device to have on/off tuned characteristics under light excitation, which enhances the dynamic controllability of the filter. The designed device may have application prospects in 6G space communication. [ABSTRACT FROM AUTHOR]

Equivalent circuit modelling (ECM) is a powerful tool to study the dynamic and non-linear characteristics of Li-ion cells and is widely used for the development of the battery management system (BMS) of electric vehicles. The dynamic parameters described by the ECM are used by the BMS to estimate the battery state of charge (SOC), which is crucial for efficient charging/discharging, range calculations, and the overall safe operation of electric vehicles. Typically, the ECM approach represents the dynamic characteristics of the battery in a mathematical form with a limited number of unknown parameters. Then, the parameters are calculated from voltage and current information of the lithium-ion cell obtained from controlled experiments. In the current work, a faster and simplified first-order resistance–capacitance (RC) equivalent circuit model was developed for a commercial cylindrical cell (LGM50 21700). An analytical solution was developed for the equivalent circuit model incorporating SOC and temperature-dependent RC parameters. The solution to the RC circuit model was derived using multiple expressions for different components like open circuit voltage (OCV), instantaneous resistance (R0), and diffusional parameters (R1 and C1) as a function of the SOC and operating temperature. The derived parameters were validated against the virtual HPPC test results of a validated physics-based electrochemical model for the voltage behavior. Using the developed RC circuit model, a polynomial expression is derived to estimate the temperature increase of the cell including both irreversible and reversible heat generation components. The temperature predicted by the proposed RC circuit model at different battery operating temperatures is in good agreement with the values obtained from the validated physics model. The developed method can find applications in (i) onboard energy management by the BMS and (ii) quicker evaluation of cell performance early in the product development cycle. [ABSTRACT FROM AUTHOR]

Accurately obtaining the state of charge (SOC) and health (SOH) of all individual batteries in a battery pack can provide support for data acquisition, state estimation, and fault diagnosis. To verify the real-time performance and accuracy of the joint estimation algorithm for high-voltage battery packs composed of 96 individual cells in series, this article applies Simulink to develop a joint estimation algorithm for SOC and SOH based on the first-order RC equivalent circuit model (1RC ECM) and implements the algorithm's cyclic calling for series nodes, enhancing the algorithm's scalability. In the algorithm, the recursive least square method with fitting factor (FFRLS) is applied to calculate OCV, R0, and R1 in the time domain, and dual adaptive extended Kalman filter (DAEKF) is applied to joint estimation of SOC and SOH at multiple time scales. Finally, with the help of dSPACE and FASECU controllers, hardware in the loop (HIL) testing was completed in multiple scenarios. The results showed that the algorithm can accurately calculate the state of individual cells in real time, and even under various initial value deviations, it still has good regression performance, laying the foundation for future applications of electric vehicles. [ABSTRACT FROM AUTHOR]

Electrical engineering models often rely on complex circuit configurations that facilitate the dynamic flow of electrically charged particles within a closed conductive network. These circuits serve as essential tools for simulating and analyzing diverse electrical systems and components. This paper introduces a study on nonlinear fractional circuits modeling through the development of a stochastic neuro-computational artificial intelligent-based solver to address mathematical models governing the Fractional order Caputo–Fabrizio stiff electric circuit model (FO-CFSECM) by manipulating the knacks of layered recurrent neural networks (LRNNs) trained with Gradient-based local search algorithm (GLA). In fractional calculus, the Caputo–Fabrizio (CF) fractional order derivative (FOD) emerges as a powerful instrument, binding its capabilities to deliver remarkably accurate solutions for fractional stiff systems. The objective of this work is to exploit the numerical treatment comprehensively for the dynamics of fractal Resistor–Capacitor (RC) and fractal Resistor–Inductor (RL) circuit models by introducing the CF fractional operator. Through the application of artificial intelligence-based soft computing and advanced back-propagative deep neural networks, a deeper understanding of the behavior and distinctive characteristics inherent in these models is sought. The Levenberg–Marquardt optimizer serves as an efficient training GLA tool for learning of LRNNs weights of fractal RL/RC circuit models. The comparative studies on variants of FO-CFSECM demonstrate that LRNNs achieve an impressive mean square error (MSE) ranging from 10−9 to 10−19 and absolute error (AE) within 10−6 to 10−8. The accuracy, reliability, and efficiency of LRNNs for solving the FO-CFSECM were further validated through MSE, AE, controlling parameters of state transitions, error histograms, and correlation measures. [ABSTRACT FROM AUTHOR]

This paper investigates the self-pulsing of dielectric barrier discharges (DBDs) at low driving frequencies. In particular, (a) the dependence of current on the product pd of gas pressure p and the gas gap length d, (b) the effects of lossy dielectrics (in resistive discharges) and large dielectric permittivity (in ferroelectrics) on current dynamics, (c) the transition from Townsend to a dynamic capacitively coupled plasma (CCP) discharge with changing pd values, and (d) the transition from Townsend to a high-frequency CCP regime with increasing the driving frequency. A one-dimensional fluid model of argon plasma is coupled to an equivalent RC circuit for lossy dielectrics. Our results show multiple current pulses per AC period in Townsend and CCP discharge modes which are explained by uncoupled electron–ion transport in the absence of quasineutrality and surface charge deposition at dielectric interfaces. The number of current pulses decreases with an increasing applied frequency when the Townsend discharge transforms into the CCP discharge. The resistive barrier discharge with lossy dielectrics exhibits Townsend and glow modes for the same pd value (7.6 Torr cm) for higher and lower resistances, respectively. Finally, we show that ferroelectric materials can amplify discharge current in DBDs. Similarities between current pulsing in DBD, Trichel pulses in corona discharges, and subnormal oscillations in DC discharges are discussed. [ABSTRACT FROM AUTHOR]

The state of charge (SOC) is an important indicator for evaluating a battery management system (BMS), which is crucial for the reliability, performance, and life management of a battery. In this paper, the characteristics of a Li-ion battery are deeply studied to explore the charge/discharge curve under different environments. Meanwhile, a second-order RC equivalent circuit model is constructed. The function identification of the EMF and SOC is performed based on the least squares method. The model estimation error is verified by simulation to be less than 0.05 V. Based on the Suboptimal Multiple Fading Factor Extended Kalman Filter (SMFEKF) algorithm, the SOC under constant current and UDDS conditions are estimated. Matlab/simulink simulations illustrate that the estimated accuracy of the proposed algorithm is improved by 79.36% compared with the EKF algorithm. Finally, the validity of the algorithm is verified jointly with the BMS. The results show that the estimation error is within 4% in both constant current condition as well as UDDS conditions, and it can still be predicted quickly and accurately under the uncertainty in the initial value of the SOC. [ABSTRACT FROM AUTHOR]

This paper introduces an analog integrated fractional order type-2 fuzzy PID control system. Current approaches frequently depend on energy-intensive embedded digital systems, consuming substantial energy levels ranging from a few μW to mW. To address this limitation we propose a fully analog design offering insights into the potential of analog circuits for powerefficient robust control in complex and uncertain environments. It consists of Gaussian function, min/max, Operational transcoductance amplifier circuits and Resistor-Capacitor networks for the implementation of the fractional-order components. Crafted for operation under a reduced voltage supply (0.6 V), the controller attains minimal power usage (861.8 nW), facilitating uninterrupted, extended-term functioning. Post-layout simulation results confirm the proper operation of the proposed design. The proposed system is designed and simulated using the Cadence IC Suite in a TSMC 90 nm CMOS process. [ABSTRACT FROM AUTHOR]

It is shown that a passive circuit, consistng of a cascade of two properly designed parallel-T RC networks, can act as a wideband rejection or selective filter. It is thoroughly analyzed and simulated. The bandpass version is an RC analog of a double tuned circuit, as commonly employed in wideband amplification in lumped realizations. The circuit presented here is amenable to IC fabrication, if the crossover can be avoided. [ABSTRACT FROM AUTHOR]

The Von Neumann architecture has been the foundation of modern computing systems. Still, its limitations in processing large amounts of data and parallel processing have become more apparent as computing requirements increase. Neuromorphic computing, inspired by the architecture of the human brain, has emerged as a promising solution for developing next-generation computing and memory devices with unprecedented computational power and significantly lower energy consumption. In particular, the development of optoelectronic artificial synaptic devices has made significant progress toward emulating the functionality of biological synapses in the brain. Among them, the potential to mimic the function of the biological eye also paves the way for advancements in robot vision and artificial intelligence. This review focuses on the emerging field of optoelectronic artificial synapses and memristors based on low-dimensional nanomaterials. The unique photoelectric properties of these materials make them ideal for use in neuromorphic and optoelectronic storage devices, with advantages including high carrier mobility, size-tunable optical properties, and low resistor–capacitor circuit delay. The working mechanisms, device structure designs, and applications of these devices are also summarized to achieve truly sense-storage-computer integrated optoelectronic artificial synapses. [ABSTRACT FROM AUTHOR]

Synaptic devices that mimic biological neurons have attracted much attention for brain-inspired neuromorphic computing. Especially, synaptic thin-film transistors (TFTs) have emerged with simultaneous signal processing and information storage advantages. However, the analysis of excitatory postsynaptic current (EPSC) relies on an empirical model such as a serial RC circuit, which limits a systematic and in-depth study of synaptic devices in terms of material and electrical properties. Herein, the single-pulse-driven synaptic EPSC (SPSE) model, including capacitive effect and information of the synaptic window, is analytically proposed. The SPSE model can simulate EPSC of synaptic devices at given TFT-operating conditions. EPSC with the SPSE model can be characterized with quantified parameters for the capacitive effects and the synaptic windows, which also depend on the electrical condition applied to TFTs. Various kinds of synaptic-TFTs with different gate insulators (e.g., SiO2 and ion-gel) are used to confirm the performance of the SPSE model. For example, the SPSE model can capture the long-term robustness of ion-gel-based TFTs with specific quantified parameters. In addition, the SPSE model enables the estimation of energy consumption, which can potentially be leveraged to compare the energy cost of EPSC fairly. The SPSE model can provide a guideline to understand the physical properties of synaptic TFTs. [ABSTRACT FROM AUTHOR]

The development of a secure battery management system (BMS) for electric vehicles depends heavily on the correct assessment of the online state-of-charge (SOC) of Li-ion batteries. The ternary lithium battery is used as the research object in this paper, and a second-order RC equivalent circuit model is developed to characterize the dynamic operating characteristics of the battery. In order to solve the problem that the adaptive unscented Kalman filter (AUKF) algorithm is easy to fail SOC estimation because the error covariance matrix is not positively definite due to the incomplete accuracy of the equivalent circuit model, a corresponding solution is proposed. Considering the poor real-time battery SOC estimate caused by the battery model's fixed parameters, therefore we propose the Variable Forgetting Factor Recursive Least Squares (VFFRLS) algorithm for joint estimation of Li-battery SOC and the Singular Value Decomposition-AUKF (SVD-AUKF) algorithm. The SVD-AUKF algorithm can accurately estimate the SOC of the battery when the error covariance is negative. The algorithm can be adaptively adjusted in both the parameter identification and SOC estimation stages, which can effectively solve the problem of poor estimation accuracy caused by fixed parameters. According to experiments, under two separate dynamic operating situations, the joint estimation algorithm's error is less than 2%, and its stability has also been greatly enhanced. At the same time, when the initial SOC value is set incorrectly, the convergence time of the algorithm proposed in this paper can reach within 2.1 seconds for BBDST and DST conditions, which can be well adapted to complex working conditions. [ABSTRACT FROM AUTHOR]

In this paper, we report the electrical properties of Al/p-Cu2ZnSnS4 thin film Schottky diode fabricated by a two-step method. Cu2ZnSnS4 ingot was successfully grown by direct melting of the constituent elements, then (CZTS) thin film was grown using thermal evaporation method onto heated Mo substrate temperature at 100 °C. After that, the as-deposited CZTS sample were annealed in a sulfur atmosphere at 400 °C for 30 min. X-ray diffraction analysis reveals a polycrystalline CZTS preferentially oriented along a (112) plane in kesterite structure. For bulk material, the band gap energy is about 1.39 eV, the complex impedance plots display a semicircle with an equivalent circuit consisting of a parallel RC circuit connected to a series resistor. The CZTS thin film was investigated in the way of structural and electrical properties. Raman spectra ensured formation of kesterite CZTS phase. Dense and polycrystalline surface features were observed in SEM images of CZTS thin film. The I–V characteristics showed that a Schottky contact was obtained between Aluminum and p-Cu2ZnSnS4 absorber layer. Characteristic parameters such as saturation current, ideality factor and series resistance were calculated from the experimental I–V data. These parameters showed significant electrical properties such as low series resistance and an ideality factor between 1 and 2. Finally, the Arrhenius diagram provided a very low activation energy of about 2.03 meV. [ABSTRACT FROM AUTHOR]

This work aims to demonstrate that chronoamperometry is a valuable tool for determining diffusivities in all‐solid‐state nanometer‐thick cells. The transient current in chronoamperometry of electrochemical cells under constant voltage is described by firstly considering purely capacitive processes, defined by RC circuit equations, and then purely diffusive processes, by Cottrell's equations. The physical meaning of the equations has been amply described in liquid cells with porous electrodes but scarcely in solid‐state cells. Thus, we studied Metal/Insulator/Metal nano‐cells with Ru and Au electrodes, Yttria Stabilized Zirconia (YSZ) electrolyte at temperatures between 50 and 170°C and voltages between 0.5 V and 1.5 V, where non‐Faradaic processes occur. The calculated diffusive and capacitive contributions at different temperatures obey the Arrhenius law. The activation energy was associated with vacancies, the major carrier during electrical transport. The analysis discusses other parameters, such as capacitance, effective concentration, and leakage current. The experimental diffusivity of YSZ electrolytes was compared with diffusivity values obtained by the statistical moment method. [ABSTRACT FROM AUTHOR]

This paper presents a very simple circuit that is able to measure capacitors capacitance, based on the estimation of capacitors discharge time. The proposed prototype is able to compute the time required by a capacitor to discharge three fourths of the stored energy. For that, a simple RC circuit is used, composed of the capacitor under test and some resistors, two operational amplifiers, which are used to identify the starting and ending points of the discharge time, four 4-bit counters, four BCD to 7 segment drivers and four displays of 7 segments, which show the computed capacitor capacitance. Several experimental results are presented. [ABSTRACT FROM AUTHOR]

The exploration of functional light-emitting devices and numerous optoelectronic applications can be accomplished on an elegant platform provided by rapidly developing transition metal dichalcogenides (TMDCs). However, TMDCs-based light emitting devices encounter certain serious difficulties, such as high resistance losses from ohmic contacts or the need for complex heterostructures, which restricts the device applications. Despite the fact that AC-driven light emitting devices have developed ways to overcome these challenges, there is still a significant demand for multiple wavelength emission from a single device, which is necessary for full color light emitting devices. Here, we developed a dual-color AC-driven light-emitting device by integrating the WSe2 monolayer and AlGaInP–GaInP multiple quantum well (MQW) structures in the form of capacitor structure using AlOx insulating layer between the two emitters. In order to comprehend the characteristics of the hybrid device under various driving circumstances, we investigate the frequency-dependent EL intensity of the hybrid device using an equivalent RC circuit model. The time-resolved electroluminescence (TREL) characteristics of the hybrid device were analyzed in details to elucidate the underlying physical mechanisms governing its performance under varying applied frequencies. This dual-color hybrid light-emitting device enables the use of 2-D TMDC-based light emitters in a wider range of applications, including broad-band LEDs, quantum display systems, and chip-scale optoelectronic integrated systems. [ABSTRACT FROM AUTHOR]

This paper is dedicated to dealing with the sampled measurement-based robust impulsive filter design problem for delayed Lur'e implicit hybrid systems via free-weighting matrix approach. Stochastic admissibility and H ∞ performance index for the implicit impulsive filtering error system are ensured based on a holistic impulse-time-dependent Lyapunov–Krasovskii functional, which embodies the impulse instants, time-varying delays and Markovian jump modes. The effect of sampled measurement output on the impulsive filter is considered, where the sampling moments are corresponding to the impulse instants. By applying the improved free-weighting matrix technique, the derivative of time-varying delay in implicit system states is no longer subject to the least upper bound 1. A set of linear matrix inequalities are applied to construe designing criterion for the desired mode-dependent implicit impulsive filter. The practicality of the developed approach is verified by nonlinear RC circuit. [ABSTRACT FROM AUTHOR]

We report on the discharge of the capacitance formed at the electrodes in flash experiments with yttria stabilized zirconia. The experiments were carried out by disconnecting the current, and, instead, short circuiting the electrodes through a resistor. The time dependent voltage across the resistor was measured; the ratio yielded the discharge current. The current decayed exponentially with time, as expected in an RC circuit, which allowed the measurement of the capacitance. Experiments were carried out in two ways. In one case the specimens were flashed within a glove box filled with Ar (< 1 ppm O2): these yielded electronic conductors. In the other case the specimens were flashed in ambient air: while electronically conducting in‐flash these specimens recover their prior insulating behavior as soon as the current is turned off. The stored charge was two orders of magnitude greater in the Ar experiments. Rather unexpectedly, the sign of the voltage expressed at the electrodes was opposite in experiments carried out in air and in Ar. The capacitance measured in the discharge experiments is attributed to the formation of space charge adjacent to the electrodes. In the case of Ar experiments, the capacitance is very large, approaching 1 F; in this case the space charge is expected to be constituted from ions. In the air experiments the specimen becomes insulating, trapping the electrons as a space charge. Hall effect measurements of the carrier density and X‐ray photoelectron spectroscopy characterization of electronically conducting single crystal specimen of cubic zirconia are reported. [ABSTRACT FROM AUTHOR]

Zinc–air batteries possess advantages such as high energy density, low operational costs, and abundant reserves of raw materials, demonstrating broad prospects for applications in areas like stationary power supplies and emergency power sources. However, despite significant advancements in zinc–air battery technology, a comprehensive measurement model for zinc–air battery parameters is still lacking. This paper utilizes a gas diffusion model to separately calculate the concentration polarization of zinc–air batteries, decoupling it from electrochemical polarization and ohmic polarization, simplifying the equivalent circuit model of zinc–air batteries into a first-order RC circuit. Subsequently, based on the simplified equivalent circuit model and gas diffusion model, a zinc–air battery parameter measurement technique utilizing current pulse methods is proposed, with predictions made for the dynamic voltage response during current pulse discharges. Validation of this method was conducted through single current pulses and step current pulses. Experimental results demonstrate the method's capability to accurately measure zinc–air battery parameters and predict the dynamic voltage response. [ABSTRACT FROM AUTHOR]

Quantum key distribution (QKD) can help distant agents to share unconditional secret keys, and the achievable secret key rate can be enhanced with the help of decoy-state protocol. To implement QKD experimentally, the agents are supposed to accurately transmit a number of different intensity pulses with the LiNbO3 based Mach-Zehnder (LNMZ) intensity modulator. However, the bias drift of LNMZ intensity modulator may affect the performance of a QKD system. In this letter, we reveal a simple RC circuit model to demonstrate the bias drift in the LNMZ intensity modulator. And based on the model, we propose a multi-step bias stable scheme to control the bias working point. Experimental result shows that our scheme can eliminate the bias drift of at arbitrary working point within a long time range. Besides, there is no need of any feedback mechanisms in the scheme. This means our scheme will not lead to any increasement in system complexity, making it more suitable for a QKD system. [ABSTRACT FROM AUTHOR]

The main objectives of this research are to derive a modified retardation time parameter of the Kelvin model in terms of the coefficient of consolidation of the 1D‐consolidation equation and to design and implement an educational LabVIEW program linked with Arduino‐Uno microcontroller as data acquisition devices for practical verification of the results inside the classroom. Consolidation coefficients of the derived equation decrease with increasing retardation time parameters of the Kelvin model. The regression module of the educational program shows a negative power of fit with an MSE of (0.134), and a 1:1 scatter plot between the derived equation and the 1D‐consolidation equation, indicating a complete fit between both equations. The derived negative power fit equation of the educational program has led to a new expression of the stress ratio of the dashpot unit of the Kevin model. The altered Kelvin dashpot stress ratio is verified experimentally using a resistance‐capacitance (RC) circuit connected to the microcontroller and linked with the educational program. The RC circuit, Arduino‐Uno, and the LabVIEW educational program are "useful" tools in teaching the rheology of soil mechanics inside the classroom. The practicality of the RC circuit for simulating the rheology of soil mechanics inside the classroom enhances the student's understanding and improves their standards in the rheology of soil mechanics. [ABSTRACT FROM AUTHOR]

The article provides updates and resources for the 2024-2025 Advanced Placement (AP) Physics exams. The exams will now consist of a two-part structure: 40 multiple-choice questions and 4 free-response questions. The multiple-choice questions have been simplified and standardized, and the free-response section has been standardized across all exams. There are specific changes and corrections for each exam, including the inclusion of qualitative treatment of RC circuits in AP Physics 2. The exams will also transition to digital format in 2025. Teachers and students will have access to free online practice resources to support the transition. [Extracted from the article]

This article describes an experiment that turns a standard function generator into a wireless function generator by connecting it to an LED lamp. The signal is transmitted via light to a receptor consisting of a small solar cell connected to the circuit. This Li-Fi-inspired setup increases student motivation for laboratory experiments on circuits. The article also includes a simple and portable experiment that transmits sound through light using a mobile phone, LED, solar cell, and speakers. The authors acknowledge the support of the Institute of Education Sciences at the Technical University of Valencia and funding from the Ministerio de Universidades, Spain. [Extracted from the article]

This paper discusses possibilities to explain which Kv channels can be considered as first-order systems. This means that the dynamic behavior of these channels can be described with a first-order differential equation and are the most straightforward dynamical systems. For example, a typical first-order system is an RC circuit, and analogously, Kv channels can be considered with the dynamic behavior of first-order systems following RC circuits. This work represents a family of KV channels that can be described as first-order systems, providing an efficient method of ion channel modeling in computational electrophysiology. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a novel Resistive Random‐Access Memory (RRAM) read circuit has been designed and verified by simulation based on the RRAM model and parasitic capacitance of the circuit. Simulation results demonstrate the feasibility and effectiveness of the proposed circuit, with accurate reading of RRAM states and fast reading speed in the nanosecond range. The sense margin of the proposed circuit has improved as the array size increases, enhancing its application for advanced node RRAM array manufacture. Compared with conventional circuits, the proposed circuit achieved power consumption reduction of 6% and area reduction of 46.9 um2, resulting in a 97.5% reduction in area, providing an effective solution to address the cost and chip size challenges associated with RRAM industrialization.

In this paper, the stochastic sampled-data exponential synchronization problem for Markovian jump neural networks (MJNNs) with time-varying delays and the reachable set estimation (RSE) problem for MJNNs subjected to external disturbances are investigated. Firstly, assuming that two sampled-data periods satisfy Bernoulli distribution, and introducing two stochastic variables to represent the unknown input delay and the sampled-data period respectively, the mode-dependent two-sided loop-based Lyapunov functional (TSLBLF) is constructed, and the conditions for the mean square exponential stability of the error system are derived. Furthermore, a mode-dependent stochastic sampled-data controller is designed. Secondly, by analyzing the unit-energy bounded disturbance of MJNNs, a sufficient condition is proved that all states of MJNNs are confined to an ellipsoid under zero initial condition. In order to make the target ellipsoid contain the reachable set of the system, a stochastic sampled-data controller with RSE is designed. Eventually, two numerical examples and an analog resistor–capacitor network circuit are provided to show that the textual approach can obtain a larger sampled-data period than the existing approach. [ABSTRACT FROM AUTHOR]

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

Time constant equilibration reduction (TICER) is a local model reduction method based on Gaussian elimination for RC networks which was introduced in Sheehan (1999 IEEE/ACM international conference on computer-aided design. Digest of technical papers (Cat. No.99CH37051), pp 200–203, 1999). The main idea of TICER is selectively removing the non-port nodes of the circuits to produce a smaller RC circuit. Since proposed, TICER has been widely used in the electronic engineering, and lots of practices validate its reliability and robustness. It is a practical method to meet the needs of reduction and can produce a realizable RC circuit with good accuracy, and this is the reason why TICER has been used until now. Later, many scholars proposed RC-realizable reduction methods based on TICER. Quite surprisingly, as far as the authors know, there exists no rigorous analysis on this simple but wonderful method in the literature. In this short communication, we prove the optimal first-order asymptotic accuracy of TICER and present numerical evidences to validate our theoretical results. [ABSTRACT FROM AUTHOR]

In this research, we investigate a resistor capacitor electric circuit that exhibits an exponentially decaying transient response. Due to uncertainty in the precise capacitance value, we treat the capacitance as a continuous uniformly distributed random variable. Using this approach, we derive the desired transient current response of the circuit as a function of the capacitance. Subsequently, we develop a probability model for the response current, expressed in terms of probability density function and cumulative distribution function. The model's validity and correctness are verified, and it is further utilized for probabilistic analysis of the transient current. We demonstrate the application of the model for determining the probability of the transient current response reaching a specific value. By following the same procedure used to derive the probability model of the transient current, probability distributions for other circuit parameters, such as voltages and currents, can also be obtained. Furthermore, for parameters that are functions of the transient current, the probability model can also be obtained from the already derived probability model. To illustrate this, we derive the probability models of three other parameters in the circuit from the already obtained models. We also present examples to demonstrate the usage of the developed probability models. [ABSTRACT FROM AUTHOR]

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

Computing and neuromorphic engineering areas have gained notoriety over the past few years. The current paradigm of computing, based on a centralized system, is an obstacle to evolution. It is necessary to leave Von Neumann's paradigm behind and invest in a more organic and decentralized model of technology. Neuromorphic computers are not made with transistors, but with memristors, electronic components are capable of retaining memory. In this study, the aim is to analyze the behavior of a memristor based on graphene oxide (GO) doped with silver simulating the neuronal membrane and validate the operation of the resistor–capacitor (RC) circuit as a possible tool for analysis of memristor devices. Electrical analyses are carried out in two stages: first, an I × V analysis of device parameters is carried out with a picoammeter; then, a test with a developed RC circuit is carried out in three conditions: a simulated RC circuit, an experimental analysis of the same circuit, and finally, the RC circuit is associated with the memristor. Memristor device presents threshold switching, which is a desirable feature when it is required to simulate neuronal firing. In addition, when associated with the RC circuit, the curve behavior obtained for charging and discharging the capacitor becomes nonlinear. [ABSTRACT FROM AUTHOR]

With applications in cosmology, infrared astronomy and CMB survey, frequency-division multiplexing (FDM) proved to be a viable readout for transition-edge sensors (TESs). We investigate the occurrence of out-of-band resonances (OBR) which could constrain the bandwidth of the FDM readout of TES bolometers. The study includes SPICE modeling of the entire setup including the cryogenic harness, LC filters, Superconducting Quantum Interference Device (SQUID) and room-temperature amplifier. Simulation results show that the long harness (for flight model) could cause multiple reflections that generate repetitive spikes in the spectrum. Peaks of the OBR are mainly due to the parasitic capacitances at the input of SQUID. Implementing a low-pass RC circuit (snubber) at the input of the SQUID dampened the OBR. As a result, the first peak only appears around 20 MHz which is a safe margin for the 1 MHz - 3.8 MHz FDM in use in the prototype readout. Using a spectrum analyzer and broadband LNAs, we also measured the OBR for the prototype FDM readout in the laboratory up to 500 MHz. The measurement was conducted at temperatures of 50 mK and 4 K and for various biasing of the DC SQUID. It turns out that OBRs are more intense at 50 mK and are caused by the harness impedance mismatch rather than the SQUID. Simulation codes and supporting materials are available at https://github.com/githubamin/LT-Spice-Simulation-of-FDM-readout. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article describes the results of research aimed at identifying the parameters of the equivalent circuit of a lithium-ion battery cell, based on the results of HPPC (hybrid pulse power characterization) tests. The OCV (open circuit voltage) characteristic was determined, which was approximated using functions of various types, while making their comparison. The internal impedance of the cell was also identified in the form of a Thevenin RC circuit with one or two time constants. For this purpose, the HPPC pulse transients were approximated with a multi-exponential function. All of the mentioned approximations were carried out using an original method developed for this purpose, based on the PSO (particle swarm optimization) algorithm. As a result of the optimization experiments, the optimal configuration of the PSO algorithm was found. Three different cognition methods have been analyzed here: GB (global best), LB (local best), and FIPS (fully informed particle swarm). Three different swarm topologies were used: ring lattice, von Neumann, and FDR (fitness distance ratio). The choice of the cognition factor value was also analyzed, in order to provide a proper PSO convergence. The identified parameters of the cell model were used to build simulation models. Finally, the simulation results were compared with the results of the laboratory CDC (charge depleting cycle) test. [ABSTRACT FROM AUTHOR]