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Solid-state nanopores offer a range of distinct advantages over biological nanopores, such as structural diversity and greater stability and durability; this makes them highly promising for high-resolution nanoparticle sensing. Biological nanopores can exhibit gating characteristics with stress-responsive switches and can demonstrate specificity toward particular molecules. Drawing inspiration from biological nanopores, this paper introduces a novel polymer nanopore with field-effect characteristics, leveraging a conductive polymer in its construction to showcase intriguing gating behavior. Notably, in this device, the polymer layer serves as the gate, enabling precise control over the source–drain current response inside and outside the pore by simply adjusting the gate voltage. This unique feature allows fine-tuning of the nanopore's sensitivity to nanoparticles of varying sizes and facilitates its operation in multiple modes. Experimental results reveal that the developed polymer nanopore field-effect transistor demonstrates remarkable selectivity in detecting nanoparticles of various sizes under different applied voltages. The proposed single device demonstrates the exceptional ability to detect multiple types of nanoparticle, showcasing its immense potential for a wide range of applications in biological-particle analysis and medical diagnostics. ARTICLE HIGHLIGHTS: • Sub-100-nm nanopipettes were processed by glass-capillary pulling, electrodeposition, and electropolymerization. • The reduction in nanopore tip diameter due to polymer deposition improves the efficiency of the detection of nanoparticles with different sizes, materials, and electrical properties. • By modulating the bias applied to the polymer at the nanopore tip, flexible regulation of nanoparticle translocation events can be achieved. [ABSTRACT FROM AUTHOR]

With a rapid advance of the technology, side-channel attacks are gaining more attention in the security evaluation of electronic devices. The impact of the attacks on medical devices can be very dangerous: from retrieving private health data to attacking implantable devices causing life-threatening situations. This paper investigates the vulnerabilities of ECG characterization devices to power side-channel attacks and proposes power supply voltage modulation as a countermeasure. Experimental results indicate that random voltage modulation can effectively obscure heart rate retrieval from leaked power signals. Sine modulation is less effective and can be canceled by demodulation at the sine frequency visible in the leaked signal spectrum. [ABSTRACT FROM AUTHOR]

Due to the hysteresis characteristics of electrowetting display, the luminance of the same driving voltage is different in the voltage rising stage and the voltage falling stage. In this paper, a gray distortion correction method for hysteresis characteristics of electrowetting display is proposed. Firstly, by measuring the influence of hysteresis characteristics on the photoelectric curve under different voltage ranges, the hysteresis curve model of electrowetting display was established by fitting the measured data. Based on this, the driving voltage mapping relationship of the same gray scale in different scenes is constructed, and finally the effect of reducing the luminance difference is achieved to reduce the gray distortion. Experimental results show that the proposed scheme can effectively reduce the degree of distortion, and the maximum gray‐scale relative luminance difference is reduced from 20.07% to 0.01%, and the reduction ratio is 99.93%. The relative luminance difference was reduced by 10.84% on average, and the reduction ratio was 80.98%. The oil aperture ratio distortion is reduced from 5.67% to 0.13%, and the reduction ratio is 97.7%. [ABSTRACT FROM AUTHOR]

Under the same experimental conditions, the processes of adsorption and the heterogenous reaction of dissociation on the surface and thermal desorption of C17H19NO3 morphine molecules with m/z 285 amu on the surface of oxidized tungsten are studied by the nonstationary surface ionization, such as the voltage modulation and flux modulation methods. The experiments are carried out using a high-vacuum mass spectrometer, in which a "black chamber" is used, all walls of which are cooled with liquid nitrogen. The kinetic characteristics of the processes of thermal desorption and the heterogeneous reaction of the dissociation of molecules on the surface, such as the rate constant of thermal desorption in the ionic and neutral states K+ and K0, the corresponding activation energies of thermal desorption E+ and E0, the pre-exponential factors C and D, as well as the rate constant of the heterogeneous dissociation reaction K d and the activation energy of heterogeneous reaction of dissociation on the surface, exponential factors in the equation of continuity of the surface concentration for C9H7N+CH3 radicals with m/z 144 amu during the adsorption of morphine molecules on the surface of oxidized tungsten are determined. [ABSTRACT FROM AUTHOR]

In this paper, the distortion of the transistor laser (TL) has been analysed. The typical diode laser and transistor lasers support not only for current controlled modulation but also in the voltage-controlled modulation. We investigate the small signal voltage modulation features of transistor lasers (TL) using FK absorption related to optoelectronic feedback and rate equations for diode lasers, and this model physically includes the various FK absorption effects. Due to Franz Keldysh (FK) absorption, an optically induced current drastically alter the voltage response in transistor lasers. The voltage modulation characteristics in transistor lasers have proposed an optical response method and an electrical function for which this optical response is fed back. [ABSTRACT FROM AUTHOR]

Common-mode voltage can be reduced effectively by optimized modulation methods without increasing additional costs. However, the existing methods cannot satisfy the requirements of the vehicular electric-drive application. This paper optimizes the tri-state voltage modulation method to reduce the common-mode voltage for vehicular electric drive system applications. Firstly, the discontinuous switching issue during sector transition is analyzed. Under the limit of two switching times in one period, multiple alignments combination is proposed to address that issue. Secondly, the zero-voltage time intervals in different modulation ranges are explored. This paper proposes an unsymmetric translation method to reconstruct the voltage vector, and then the minimum zero-voltage time interval is controlled to enough value for safe switching. Finally, the proposed methods have been validated through experiments on a vehicular electric drive system. The results show that the common-mode voltage can be reduced effectively in the whole range with the optimized tri-state voltage modulation method.

Small dc-link drive systems, built with film capacitors in the dc-link, present a new trend in many industrial applications and are obtaining increasing interests. It has the advantages of longer lifetime and the possibility to achieve a more compact design of the capacitor bank, especially at medium and high power rates. However, it could exhibit instability problems, mainly in the form of oscillations. The unexpected oscillation may result in overvoltage and shorten the lifetime of the power devices and the dc-link capacitors; increase the total harmonic distortion and also the partially weighted harmonic distortion of the grid supply current. Therefore, active damping methods are usually needed in order to stabilize such drive systems. This paper first analyzes the system characteristics and the principles of existing active damping methods. Then, a new voltage modulation based method named as “virtual positive impedance” method is introduced to guarantee the dc-link stability. This new approach is simple to apply and its implementation does not require the knowledge of system parameters and machine operating conditions. The proposed method is analyzed in details and verified by experiments. [ABSTRACT FROM AUTHOR]

This study adopts the method of third-order harmonic voltage injection (THVI) to move the peak value of a reference voltage toward the high capacitor voltage and increase the utilization rate of the capacitor voltage. This method can lower the cost or enlarge the capacity of a modular multilevel converter (MMC) when applied in high-voltage direct-current transmission. In this paper, the principle of THVI is introduced. Two calculation methods for modulation waves are studied, and the mathematical expressions of the capacitor voltage under all operating conditions are deduced. Thus, the optimal magnitude and phase of the third-order harmonic voltage are determined under all operating conditions. The mathematical expressions of the optimal magnitude and phase of the third-order harmonic voltage are obtained, and their online calculation burden is reduced. Simulation and experimental results show that the proposed method of THVI is feasible and effective. [ABSTRACT FROM PUBLISHER]

For maintaining a reliable and secure power system, this paper describes the design and implement of a single-phase grid-connected inverter with an enhanced phase-locked loop (PLL) and excellent power control performance. For designing the enhanced PLL and power regulator, a full-bridge voltage-controlled inverter (VCI) is investigated. When the grid frequency deviates from its reference values, the output frequency of the VCI is unstable with an oscillation of 2 doubling harmonics. The reason for this oscillation is analyzed mathematically. This oscillation leads to an injection of harmonics into the grid and even causes an output active power oscillation of the VCI. For eliminating the oscillation caused by a PLL, an oscillation compensation method is proposed. With the proposed method, the VCI maintains the original PLL control characteristics and improves the PLL robustness under grid frequency deviations. On the basis of the above analysis, a power regulator with the primary frequency and voltage modulation characteristics is analyzed and designed. Meanwhile, a small-signal model of the power loops is established to determine the control parameters. The VCI can accurately output target power and has primary frequency and voltage modulation characteristics that can provide active and reactive power compensation to the grid. Finally, simulation and experimental results are given to verify the idea. [ABSTRACT FROM AUTHOR]

We report a MEMS fabrication and frequency sweep for a high-order mode suspending beam and plate layer in electrostatic micro-gap semiconductor capacitor. This suspended beam and plate was designed with silicon oxide (SiO 2 ) film which was fabricated using bulk silicon micromachining technology on both side of a silicon substrate. The designed semiconductor capacitors were driven by a bias direct current (DC) and a sweep frequency alternative current (AC) in a room temperature for an electrical response test. Finite element calculating software was used to evaluate the deformation mode around its high-order response frequency. Compared a single capacitor with a high-order response frequency (0.42 MHz) and a 1 × 2 array parallel capacitor, we found that the 1 × 2 array parallel capacitor had a broader high-order response range. And it concluded that a DC bias voltage can be used to modulate a high-order response frequency for both a single and 1 × 2 array parallel capacitors. [ABSTRACT FROM AUTHOR]

The Navy's future and near-term high-energy sensors and energy weapons will consume a large portion of the resources of the intended ship platform. Many of these new systems will have extreme dynamic power profiles, including both periodic and aperiodic characteristics. These dynamics can cause sudden changes in power at the prime power system that can be stressing to platform systems, both to the generators and prime movers as well as other loads sharing the common distribution bus. This paper presents the use of a new adaptive power system (APS) to mitigate the negative impacts levied on the platforms resulting from large dynamic loads. A notional size of the hardware required to implement the APS design is presented along with simulation results verifying the concept. [ABSTRACT FROM AUTHOR]

The influence of voltage on the conductance of toad skin was studied to identify the time course of the activation/deactivation dynamics of voltage-dependent Cl- channels located in the apical membrane of mitochondrion-rich cells in this tissue. Positive apical voltage induced an important conductance inhibition which took a few seconds to fully develop and was instantaneously released by pulse inversion to negative voltage, indicating a short-duration memory of the inhibiting factors. Sinusoidal stimulation at 23.4 mM [Cl-] showed hysteresis in the current versus voltage curves, even at very low frequency, suggesting that the rate of voltage application was also relevant for the inhibition/releasing effect to develop. We conclude that the voltage modulation of apical Cl- permeability is essentially a fast process and the apparent slow components of activation/deactivation obtained in the whole skin are a consequence of a gradual voltage build-up across the apical membrane due to voltage sharing between apical and basolateral membranes

A linearized intensity modulator for pulsed light based on an injection-locked mode-locked laser (MLL) is presented here. This has been realized by introducing a monolithic Fabry-Pérot MLL into one of the arms of a conventional Mach-Zehnder interferometer (MZI) and injection-locking it to a MLL which is the input to the interferometer. By modulating the current on the gain section or the voltage of the saturable absorber (SA) section of the injection-locked laser, one can introduce an arcsine phase response on each of the injected longitudinal modes. By combining the modulated optical comb with its unmodulated counterpart one can produce a linearized intensity modulator. The linearity of this modulator is inherent in its design and no pre- or postdistortion linearization scheme is utilized. The results of the two-tone intermodulation experiment are presented here for this modulator and a spur-free dynamic range (SFDR) of ~70 dB·Hz2/3 is achieved by modulating the voltage of the SA. The reported SFDR is limited by the noise of the MLLs. The dynamic range could be further improved by decoupling the phase modulation and amplitude modulation. The proposed and demonstrated configuration as an analog optical link with improved linearity has the potential to increase the performance and resolution of photonic analog-to-digital converters (ADCs). [ABSTRACT FROM PUBLISHER]

The adsorption and surface ionization of codeine molecules С 18 H 21 O 3 N ( m/z 299) on the surface of oxidized tungsten have been studied by a non-stationary method of voltage modulation under the same experimental conditions with a high-vacuum mass-spectrometric setup using a "black chamber" all walls of which are cooled with liquid nitrogen. For the codeine molecule dissociation with the ( C - C 1 ) β bond breaking and formation of ionizable radicals, the rate constants K + and K 0 , the activation energy Е + and Е 0 of thermodesorption, and the pre-exponential factors in the continuity equation for the radicals C 9 H 7 N + CH 3 ( m/z 144) have been defined by surface ionization on the surface of oxidized tungsten W x O y . The results of determining the surface ionization coefficient and estimates of the ionization potentials of these radicals have been presented.

First, the analytic expressions of fundamental wave and each order of harmonic wave for the output voltage is calculated by the Fourier decomposition method, which is used to analyze the modulation ratio of the three-phase inverter modulated by wavelet modulation. Then, the equation of the voltage modulation ratio (M) is derived and the scope of M is obtained by calculation, giving the range of the linear modulation for the three-phase inverter under the wavelet modulation. Finally, the correctness and rationality of the theoretical analysis is validated by computer simulation. The research result shows that the output voltage quality under the wavelet modulation is better than that under SPWM and SVPWM when the switch frequency is equal to the modulation ratio. In addition, the range of linear modulation under wavelet modulation is larger than that under SPWM and SVPWM. [ABSTRACT FROM AUTHOR]

In high performance digital systems as well as in RF systems, voltage scaling and modulation techniques have been adopted to achieve a more efficient processing of the energy. The implementation of such techniques relies on a power supply that is capable of rapidly adjusting the system supply voltage. In this paper, a pulsewidth modulation multiphase topology with magnetic coupling is proposed for its use in voltage modulation techniques. Since the magnetic coupling in this topology is done with transformers instead of coupled inductors, the energy storage is reduced and very fast voltage changes are achieved. Advantages and drawbacks of this topology have been previously presented in the literature and in this paper, the design criteria for implementing a power supply for the envelope elimination and restoration technique in an RF system are presented along with an implementation of the power supply. [ABSTRACT FROM AUTHOR]

Data are presented showing open-eye 20-Gb/s transmission for a quantum-well transistor laser operating at room temperature (25^\circC). The fast spontaneous recombination lifetime (\sim30~ps) in the base region results in a resonance-free frequency response allowing demonstration of 20-Gb/s transmission with an I/ITH=3. It is shown that higher temperature hastens the transition to the first excited state and improves bandwidth and eye-opening at low bias levels (I/ITH=2). In addition, room temperature 20-Gb/s transmission through voltage modulation of a transistor laser via intracavity photon-assisted tunneling in the base-collector junction is reported. [ABSTRACT FROM PUBLISHER]

Abstract: We consider a superconducting quantum interference device having two arbitrary different over damped junctions transporting different currents. By replacing the governed two-dimensional Fokker–Planck equation with two one-dimensional equations, two density probability currents are appeared which determine the statistical average of the time-averaged total voltage across the device. To obtain the density probability currents, two coupled integral equations are introduced. These equations together with two other equations coming from normalizing conditions, found one generalized formulation for the voltage–current characteristics of the device. Based on that, the voltage–current characteristics of large inductance asymmetric DC SQUIDs having first and second harmonics in their current-phase relations are obtained and some predictions are illustrated. [Copyright &y& Elsevier]

Characteristics of equivalent area method of the nearest level modulation (NLM) is analysed in detail and an improved NLM for ten or so cells of cascaded H‐bridge (CHB) converter with a high modulation precision is proposed. The proposed algorithm can make the output voltage of the CHB converter better track the voltage modulation. Simulation results are presented to verify the validity of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Common-mode voltage can be reduced effectively by optimized modulation methods without increasing additional costs. However, the existing methods cannot satisfy the requirements of the vehicular electric-drive application. This paper optimizes the tri-state voltage modulation method to reduce the common-mode voltage for vehicular electric drive system applications. Firstly, the discontinuous switching issue during sector transition is analyzed. Under the limit of two switching times in one period, multiple alignments combination is proposed to address that issue. Secondly, the zero-voltage time intervals in different modulation ranges are explored. This paper proposes an unsymmetric translation method to reconstruct the voltage vector, and then the minimum zero-voltage time interval is controlled to enough value for safe switching. Finally, the proposed methods have been validated through experiments on a vehicular electric drive system. The results show that the common-mode voltage can be reduced effectively in the whole range with the optimized tri-state voltage modulation method. [ABSTRACT FROM AUTHOR]

Abstract: We analyze transient current data during the formation of titanium oxide nanodots by AFM-tip-induced anodic oxidation with the aim of getting further understanding of local oxidation kinetics. The measured current waveforms show a transition between two distinct regimes, in agreement to what was previously known of the growth process, and their behavior is discussed with respect to the oxide growth rate and to the formation of the space charge. Furthermore, it is shown how the knowledge of the duration of the first transient regime can be exploited to optimize the application of pulsed bias voltages to obtain a substantial improvement in aspect ratio of growing oxides. [Copyright &y& Elsevier]

A voltage modulation technique was applied for the precise and accurate determination of manganese in steels in dc glow discharge optical emission spectrometry. Emission signals from the glow discharge plasma are modulated by a cyclic variation of the discharge voltage so that only the desired signals can be detected at very low noise levels by using a lock-in amplifier. Mn determination in low-alloyed steels was performed to estimate the repeatability of the analytical result. For each measurement, the relative standard deviation (R.S.D.) of the intensities of the Mn I 403.08-nm line was ca 0.1% when a steel sample containing 0.329 mass% Mn was employed. Averaging all analytical values, which are obtained in various discharge conditions, yields statistical information on the precision and accuracy of the analytical values obtained. The relative error from the recommended value is calculated to be 0.5%. The R.S.D. over the analytical values is 1.5%, representing the overall analytical performance of this technique. [Copyright &y& Elsevier]

High-temperature superconducting Josephson junctions and dc SQUIDs were fabricated using a ramp edge-geometry SNS configuration. Ag-doped YBa/sub 2/Cu/sub 3/O/sub 7-x/ was used as electrodes and PrBa/sub 2/Cu/sub 3/O/sub 7-x/ as barrier. The I/sub c/R/sub n/ value of the junctions was in excess of 120 /spl mu/V at 75 K. The dc SQUIDs showed a flux modulation depth, /spl part/V//spl part//spl Phi/, over 150 /spl mu/V//spl Phi/, at 75 K. The flux noise of the devices, measured with dc bias currents operated at 75 K, showed a 1/f dependence at low frequency having values below 100 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 / (the best values in the range of 30/spl sim/40 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 /) at 1 Hz and less than 5 /spl mu//spl Phi//sub 0/Hz/sup - 1/2 / in the white noise region. The voltage modulation and magnetic field noise were 37 /spl mu/V and /spl sim/2 pTHz/sup - 1/2 / at 1 kHz for the directly-coupled dc SQUID magnetometers (with a pick-up loop 6 mm/spl times/ 3.5 mm) based on the ramp edge-geometry SNS configuration. [ABSTRACT FROM PUBLISHER]

A new voltage-modulated active-matrix organic light-emitting diode (AMOLED) pixel design, which successfully compensates for the threshold voltage variations in poly-Si thin-film transitors (TFTs), is proposed, and verified by SPICE simulation and experiments. In order to compensate for variations in OLED current, the proposed pixel design employs a new voltage modulation scheme using diode connections. [ABSTRACT FROM AUTHOR]