General Circuit Research Articles

Энергетический комплекс на базе высокооборотной электрической машины

Purpose: The purpose of this study is to develop the scientific basis for designing high-speed electric generators used in conjunction with gas micro-turbines. Methods: To solve the tasks set, the theories of electrical machines; the finite element method; automatic control theory; methods of mathematical analysis, mathematical and circuit modeling; numerical modeling on a PC using FEMM and Matlab Simulink software complexes have been used. The research has been carried out on experimental samples of a high-speed electric generator and confirmed by the results of tests as part of an energy complex based on a gas microturbine in 2019. Results: A complex of scientifically based technical solutions for the design of a high-speed electric generator with an energy complex control system based on a micro-gas turbine has been developed. As a result, a high-speed electric generator for a gas microturbine with a power of 100 kW and a rotation speed of 100,000 rpm has been developed and manufactured. When designing, an asynchronous type electric generator with a massive rotor has been selected. A feature of the developed design is the use of a five-phase stator winding. A control system of an experimental sample of a high-speed electric generator for micro-GTU has been developed. Practical significance: It lies in the development of methods and algorithms for designing high-speed generator equipment for micro-GTU. Recommendations have been developed for choosing the type and configuration of a high-speed electric generator for an electric complex based on a micro-gas turbine. A method is proposed for calculating the parameters of the substitution circuit of a highspeed electric generator, which allows us to determine the parameters of the substitution circuit according to the known configuration of the active layer at the design stage.

Random unitaries, Robustness, and Complexity of Entanglement

It is widely accepted that the dynamic of entanglement in presence of a generic circuit can be predicted by the knowledge of the statistical properties of the entanglement spectrum. We tested this assumption by applying a Metropolis-like entanglement cooling algorithm generated by different sets of local gates, on states sharing the same statistic. We employ the ground states of a unique model, namely the one-dimensional Ising chain with a transverse field, but belonging to different macroscopic phases such as the paramagnetic, the magnetically ordered, and the topological frustrated ones. Quite surprisingly, we observe that the entanglement dynamics are strongly dependent not just on the different sets of gates but also on the phase, indicating that different phases can possess different types of entanglement (which we characterize as purely local, GHZ-like, and W-state-like) with different degree of resilience against the cooling process. Our work highlights the fact that the knowledge of the entanglement spectrum alone is not sufficient to determine its dynamics, thereby demonstrating its incompleteness as a characterization tool. Moreover, it shows a subtle interplay between locality and non-local constraints.

Carry look-ahead and ripple carry method based 4-bit carry generator circuit for implementing wide-word length adder

In this study, an approach to implement wide word-length adders is presented by proposing a hybrid 4-bit carry generator. The proposed hybrid carry generator uses a combination of Carry Look-Ahead (CLA) and Ripple Carry (RC) styles. Utilization of RC style in the first 3-bits aims to reduce transistor count along with power consumption. On the other hand, the CLA method is used in the 4th bit to ensure speed. Also, the proposed CLA for the 4th bit uses a novel approach, which uses inverted Propagate (Pi‾) - Generate (Gi‾) circuits rather than using the conventional ones. Performance of the proposed hybrid RC-CLA based 4-bit carry generator is benchmarked against existing designs. Moreover, the designs (proposed and existing) are used to implement a 16-bit adder to check the effect of using the 4-bit unit cells in a wide word length structure. The proposed design outperforms the existing ones in Average Power and Power Delay Product (PDP). As a result, the design can bring drastic performance enhancement in modern low-power battery-operated devices to reduce power consumption.

Power generation from wastewater using microbial fuel cells: A review.

As the world grapples with an imminent energy crisis brought on by the depletion of nonrenewable resources, such as petroleum, the necessity for alternative and eco-friendly power sources becomes increasingly apparent. In this regard harnessing knowledge gained from natural microorganisms to produce electricity using economical substrates is a promising solution through microbial fuel cells (MFCs). Microbial fuel cells leverage microbes' catabolic abilities to break down organic matter and release electrons that are subsequently transported across an external circuit for electricity generation. This article delves into the fundamental components involved in MFC construction and explores crucial factors that impact their performance including substrate oxidation, electron transfer, and internal resistance. Additionally, it offers a comprehensive analysis of existing microbial fuel cell designs while highlighting their respective strengths and weaknesses. Finally, the article showcases cost-effective MFC models based on thorough studies conducted worldwide while illuminating potential practical applications of this renewable energy technology.

Sharp Inequalities for Driving Point Impedance Functions

In this paper, positive real functions are considered as driving point impedance functions, Z(s), which are utilized in electrical engineering for characteristic representation of circuits. Accordingly, for the real part of Z(s), sharp inequalities are presented with their extremal functions by using zeros and poles of Z(s). For these extremal functions, corresponding generic circuit schematics are given with their spectral analyses. According to the obtained results, it has been shown that various circuits can be obtained by using the extremal functions of the inequalities presented in this study.

A Novel Microwave Noise Generator Using Multiple Zener Diodes Connected in Series

A novel microwave noise generator circuit using multiple Zener diodes connected in series was designed and tested. Measurements are presented up to 6 GHz. It is presented in this letter that when the number of series Zener diodes increases, the amount of noise power generated also increases across the band of interest. However, the increase of noise power from one-zener to two-zener configuration and from two-zener to three-zener configuration is not uniform. Measurements were limited to three zeners connected in series due to available high-voltage dc power supply.

A Capacitive Computing-In-Memory Circuit With Low Input Loading SRAM Bitcell and Adjustable ADC Input Range

We present a 9T1C SRAM cell-based capacitive computing-in-memory circuit for neural network computation. The proposed design improves tolerance against process variation with a smaller cell area compared to previous capacitive SRAM CIM designs while inheriting the advantage of capacitive SRAM CIM hardware such as the linearity in multiply-accumulate (MAC) results and suppression of the static readout current. We also demonstrate a compact and low-power ADC for CIM readout, which improves the energy efficiency significantly. Finally, we demonstrate a programmable on-chip ADC reference voltage generator circuit for adjusting the ADC input range using bitcell replica arrays. The proposed circuit reduces the ADC bit-resolution requirement by considering the distribution of MAC results, and also helps to address the effect of the parasitic bitline capacitance. Measurement results show that a 128×128 macro fabricated in a 28 nm CMOS achieves 1519.5 TOPS/W at 0.7 V.

Justification of the Prospects for Selecting the Main Electrical Equipment in the Generator Circuit of High-Power Nuclear Power Plant Units

Justification of the Prospects for Selecting the Main Electrical Equipment in the Generator Circuit of High-Power Nuclear Power Plant Units

Single-flux-quantum-based qubit control with tunable driving strength

Single-flux-quantum (SFQ) circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors. SFQ-based quantum gates have been designed and realized. However, current control schemes are difficult to tune the driving strength to qubits, which restricts the gate length and usually induces leakage to unwanted levels. In this study, we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals. This scheme not only provides a way to adjust the SFQ-based gate length, but also proposes the possibility to tune the driving strength envelope. Simulations show that our scheme can suppress leakage to unwanted levels and reduce the error of SFQ-based Clifford gates by more than an order of magnitude.

Circuit Model for Nth-Order Filtering Wire Antenna, Parameter Extraction, and Radiation Prediction

This article proposes a general circuit model for a thin wire antenna and a generalized approach to design an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N$</tex-math> </inline-formula> th-order parallel coupled wire antenna with its companion circuit model. Frequency-variant <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$</tex-math> </inline-formula> -inverters are involved in the new equivalent circuit to describe the frequency-variant radiation effect of the antenna. The design procedure starts with an initial prototype developed from a synthesized arrow coupling matrix, and then, its companion circuit is constructed accordingly. All the circuit parameters associated with the prototype can be extracted from EM models using space mapping technology. Iterative tuning is employed in the EM and circuit model, such that the final response satisfies the given specifications. An analytic method based on the circuit model is proposed to predict the radiation performance of the antenna. It is the first time ever that this type of filtering antenna has been designed and predicted quantitatively by using its circuit model, and the tuning of the antenna structure can also be guided by its circuit model. The proposed method offers a deterministic way for optimally designing an arbitrary-order filtering wire antenna with proper frequency characteristics.

INTEGRATED ENERGY SUPPLY SYSTEM OF SOLAR AND BIOGAS ENERGY DEVICES IN A MOBILE HOME

This article lists the main dimensions and parameters of a mobile home with an autonomous energy supply system based on completely alternative energy sources for consumers of heat and electricity in regions far from centralized energy supply. An integrated example of a mobile home’s general principled circuit, such as a solar collector, solar photobathare, pyrolysis, and biogas devices, is described as a mobile (portable) home-mounted view and home exterior. In addition, the article describes the Mobile Home application facility under research and the energy and economic efficiency for rural and farm clusters, fishing beekeeping industries. The article presents the sequence and principles of operation of devices installed in a mobile home.

High Dimensional Quantum Machine Learning With Small Quantum Computers

Quantum computers hold great promise to enhance machine learning, but their current qubit counts restrict the realisation of this promise. To deal with this limitation the community has produced a set of techniques for evaluating large quantum circuits on smaller quantum devices. These techniques work by evaluating many smaller circuits on the smaller machine, that are then combined in a polynomial to replicate the output of the larger machine. This scheme requires more circuit evaluations than are practical for general circuits. However, we investigate the possibility that for certain applications many of these subcircuits are superfluous, and that a much smaller sum is sufficient to estimate the full circuit. We construct a machine learning model that may be capable of approximating the outputs of the larger circuit with much fewer circuit evaluations. We successfully apply our model to the task of digit recognition, using simulated quantum computers much smaller than the data dimension. The model is also applied to the task of approximating a random 10 qubit PQC with simulated access to a 5 qubit computer, even with only relatively modest number of circuits our model provides an accurate approximation of the 10 qubit PQCs output, superior to a neural network attempt. The developed method might be useful for implementing quantum models on larger data throughout the NISQ era.

A proposed optimized equivalent circuit and performance analysis of dielectric barrier discharge ozone generator

&lt;span lang="EN-US"&gt;Traditionally, low-frequency power supplies are used in dielectric barrier discharge (DBD) ozone generators. These generators require a very high output voltage. This may limit ozone production due to limitations imposed by the dielectric strength of the insulating material. Low-frequency generators also present low efficiency, large volumes, and difficulty in controlling ozone production. On the other hand, the advantages of high frequency DBD ozone generators are the increased power density applied to the chamber electrodes, and the voltage applied to the ozone chamber decreases, allowing for higher ozone production efficiency. From this point of view, in order to enhance and control the DBD ozone generator operating at high frequency, it is necessary to determine all parameter values and optimize the equivalent model for this type of generator. This work presents and proposes the practical methodologies used to extract all parameters of the high voltage high frequency (HVHF) transformer which can be used in these systems. Resonant frequency control techniques are presented in this paper. Elimination of the stray capacitance effect will also be implemented in this paper.&lt;/span&gt;

Comparison of Different Circuit Topology for Generation of PWM Signal with High Power for Electroporation

Electroporation refers to a microbiological method which involves application of electric field to cells for ameliorating the cell membranes permeability, allowing electrode arrays, drugs and chemicals to be inserted into the cells. This process requires HV pulses or signals for creating pores within the cell membrane. As these signals are less effective, nowadays, Pulse Width Modulation (PWM) signals are extensively employed for electroporation. These signals can be exploited for constructing coveted output voltage in power amplifiers and are found to be useful for regulating power devices. Therefore, generation of top quality PWM signals is essential for achieving superior electroporation performance. Different PWM methods are available and circuit topologies employed for generating these waveforms are also different. This paper thus provides an exploratory study of distinct circuit topologies exploited for generating PWM waveforms. The review paper also provides the significance of PWM signals for electroporation. It reviews the existing circuit topologies exploited for PWM signal generation and other related studies. It also presents a circuit for PWM waveform generation. The paper then provides the substantial future directions pertaining to the study. This review article mainly educates the reader regarding existing circuit topologies for PWM signal generation, their characteristics and improvements required for developing better topologies satisfying the requisites of modern applications.

A Cryo-CMOS, Low-Power, Low-Noise, Phase-Locked Loop Design for Quantum Computers

This paper analyzes the performance requirements that need to be met by a clock generator applied to a low-temperature quantum computer and analyzes the negative effects on the clock generator circuit under low-temperature conditions. In order to meet the performance requirements proposed in this paper and suppress the negative effects brought about by the low temperature, a clock generator for ultra-low-temperature quantum computing is designed. This clock generator is designed by using F-CLASS Voltage Controlled Oscillator (VCO), power filter, tail resistor, differential charge pump, and other techniques. And the noise characteristics of the clock generator are analyzed by Impulse Sensitive Function (ISF) and simulation results. After simulation tests, the average power consumption of the clock generator designed in this paper is 7 mW, the phase noise is −121 dBc/Hz@1 MHz, and the jitter is 62 fs. The performance of the clock generator meets the performance requirements proposed in this paper, and the reduction in the corner frequency proves that the circuit will have better performance at low temperatures.

GASP: a genetic algorithm for state preparation on quantum computers

The efficient preparation of quantum states is an important step in the execution of many quantum algorithms. In the noisy intermediate-scale quantum (NISQ) computing era, this is a significant challenge given quantum resources are scarce and typically only low-depth quantum circuits can be implemented on physical devices. We present a genetic algorithm for state preparation (GASP) which generates relatively low-depth quantum circuits for initialising a quantum computer in a specified quantum state. The method uses a basis set of R_x, R_y, R_z, and CNOT gates and a genetic algorithm to systematically generate circuits to synthesize the target state to the required fidelity. GASP can produce more efficient circuits of a given accuracy with lower depth and gate counts than other methods. This variability of the required accuracy facilitates overall higher accuracy on implementation, as error accumulation in high-depth circuits can be avoided. We directly compare the method to the state initialisation technique based on an exact synthesis technique by implemented in IBM Qiskit simulated with noise and implemented on physical IBM Quantum devices. Results achieved by GASP outperform Qiskit’s exact general circuit synthesis method on a variety of states such as Gaussian states and W-states, and consistently show the method reduces the number of gates required for the quantum circuits to generate these quantum states to the required accuracy.

Water Flow Visualization And Velocity Measurement Using Hydrogen Bubble Generation Technique In Low Speed Open Channel

Visualization of water flow around different bluff bodies at different Reynolds number ranging (1505 - 2492) was realized by designing and building a test rig which contains an open channel capable to ensure water velocity range (4-8cm/s) in this channel. Hydrogen bubbles generated from the ionized water using DC power supply are visualized by a light source and photographed by a digital camera. Flow pattern around a circular disk of (3.6cm) diameter and (3mm) thickness, a sphere of (3.8cm) diameter and a cylinder of (3.2cm) diameter and (10cm) length are studied qualitatively. Parameters of the vortex ring generated in the wake region of the disk and the separation angle of water stream lines from the surface of the sphere are plotted versus Reynolds number. Proper empirical formulas are investigated to describe the behavior of vortex ring parameters and separation angle versus Reynolds number. Vortex growth history in the wake region of the cylinder is identified by analyzing the photographs extracted from the digital camera used for photography purposes. Water velocity measurement in the upstream region and near the edge of the disk is conducted at different Reynolds number by measuring the length of Hydrogen bubble pulse streaks generated in the upstream region of the disk using electronic pulse generator circuit. Special electronic circuit is designed and fabricated to cut off the applied DC voltage. The calibration of the designed pulse generator is conducted using the proper oscilloscope device. The pictures extracted from the digital camera are used for analyzing the generated Hydrogen pulses.

Kerr effect based optical switching for the assessment of all-optical sequence generator and decoder circuits

Abstract The sequence generator and decoders are used for noise analysis, signal propagation, data processing, and bit error rate analysis. The semiconductor and modern electronic components are facing challenges in terms of processing speed and data rates. However, by using photons rather than electrons as the information carriers, these difficulties can be reduced. Photonic devices attained the operating speed in the regime of terahertz, but sit back due to the diffraction limit, which can be overcome by employing plasmon-based devices or all-optical devices. This work presents a numerical investigation of metal-insulator-metal (MIM) plasmonic waveguides based two-bit sequence generator (SG) and decoder. The structure of SG and decoder circuits are designed within the footprints of 86 × 9 and 140 × 9 µm, by cascading one power splitter (PS) and four Mach-Zehnder interferometers (MZIs), and two PS and five MZI, respectively. To design the MZI, the optimization of the S-bend waveguide, the coupling length of the power splitter, and the length of the interferometric arm are done by recording the output power. The highest extinction ratio of 22.1 dB is attained at the coupling and interferometric arm lengths of 1.5 µm and 5 µm, respectively. The propagation of the optical signal through the structure of SG is observed by using a two-dimensional finite difference time domain method-based tool.

Normative and mechanistic model of an adaptive circuit for efficient encoding and feature extraction

One major question in neuroscience is how to relate connectomes to neural activity, circuit function, and learning. We offer an answer in the peripheral olfactory circuit of the Drosophila larva, composed of olfactory receptor neurons (ORNs) connected through feedback loops with interconnected inhibitory local neurons (LNs). We combine structural and activity data and, using a holistic normative framework based on similarity-matching, we formulate biologically plausible mechanistic models of the circuit. In particular, we consider a linear circuit model, for which we derive an exact theoretical solution, and a nonnegative circuit model, which we examine through simulations. The latter largely predicts the ORN [Formula: see text] LN synaptic weights found in the connectome and demonstrates that they reflect correlations in ORN activity patterns. Furthermore, this model accounts for the relationship between ORN [Formula: see text] LN and LN-LN synaptic counts and the emergence of different LN types. Functionally, we propose that LNs encode soft cluster memberships of ORN activity, and partially whiten and normalize the stimulus representations in ORNs through inhibitory feedback. Such a synaptic organization could, in principle, autonomously arise through Hebbian plasticity and would allow the circuit to adapt to different environments in an unsupervised manner. We thus uncover a general and potent circuit motif that can learn and extract significant input features and render stimulus representations more efficient. Finally, our study provides a unified framework for relating structure, activity, function, and learning in neural circuits and supports the conjecture that similarity-matching shapes the transformation of neural representations.

Multi-Objective Optimization Design of a Radial-Tangential Built-In Combined Permanent Magnet Pole Generator for Electric Vehicles

In this paper, a multi-objective optimization method is proposed to address the problem in the optimization process of the generator that only a specific index of a generator can be optimized to the neglect of other performance indices. Based on the equivalent magnetic circuit method, a mathematical model of the magnetic circuit of a radial-tangential combined permanent magnet pole generator is established, and the expression of the cogging torque including the pole offset angle is derived. The pole offset angle is proposed as the design variable, and no-load induction potential, air-gap flux density, and cogging torque are used as optimization targets. The relative optimal designs of permanent magnet generators are based on Pareto front statistics and defined parameter matching coefficients. Finally, a prototype is made based on the optimal structural parameters. According to the experimental results of the prototype, the correctness of the theoretical analysis and the effectiveness of the optimal design are verified.